JP7471468B2 - Brazing apparatus, brazing apparatus control method and program - Google Patents

Description

The present disclosure relates to a brazing apparatus, a method for controlling a brazing apparatus, and a program.

Some brazing devices have a wire formed from brazing material that protrudes from the tip of a nozzle, and the nozzle is moved using a movement mechanism to braze the desired location.

For example, Patent Document 1 discloses a brazing device that includes a nozzle through which a wire is inserted and from which the wire protrudes at the tip, and a robot that moves a wire supply unit to which the nozzle is attached.

In the brazing device described in Patent Document 1, a positioning jig is attached to the wire supply unit instead of a nozzle so that the wire protruding from the nozzle is accurately applied to the brazing point, and in this state, the brazing point is taught to the robot. This improves positional accuracy during brazing.

Japanese Patent Application Laid-Open No. 7-51842

However, in brazing equipment, a coil of wire wound on a reel is inserted into the nozzle. This means that the wire often has a tendency to bend. As a result, even if the robot is taught the exact brazing location using a positioning jig, the brazing position can still be off.

The present disclosure has been made to solve the above-mentioned problems, and aims to provide a brazing apparatus capable of performing brazing in an accurate position, and a control method and program for the brazing apparatus.

In order to achieve the above object, the brazing apparatus according to the present disclosure includes a holding mechanism, a wire supply mechanism, a position sensor, a moving mechanism, a wire tip position calculation unit , a moving mechanism control unit , a wire detection sensor, and a feed amount calculation unit . The holding mechanism holds a portion of the wire formed by the brazing material that is rearward of the tip. The wire supply mechanism feeds and supplies the wire to the holding mechanism, causing the wire to protrude from the holding mechanism. The position sensor measures the positions of each part of the wire's outer shape in a cross section that crosses an intermediate portion between the tip and the rear portion of the wire. The moving mechanism moves the holding mechanism. The wire tip position calculation unit determines the position of the tip of the wire relative to the holding mechanism when the wire protrudes from the holding mechanism by a target length, based on the positions of each part of the wire's outer shape in the intermediate portion measured by the position sensor. The moving mechanism control unit determines the amount of movement of the holding mechanism by the moving mechanism, based on the position of the tip of the wire relative to the holding mechanism determined by the wire tip position calculation unit. The wire detection sensor detects whether the tip of the wire is at a specific position on the side of the holding mechanism from which the wire protrudes. When the wire supply mechanism moves the tip of the wire to a specific position using the output of the wire detection sensor, the feed-out amount calculation unit calculates the wire feed amount based on the relative position of the specific position with respect to the holding mechanism and the value of the target length of the wire. Then, the wire supply mechanism feeds out the wire based on the wire feed amount calculated by the feed-out amount calculation unit.

According to the configuration of the present disclosure, the wire tip position calculation unit determines the position of the tip of the wire relative to the holding mechanism when the wire protrudes from the holding mechanism by a target length, based on the positions of each part of the outer shape of the wire at the middle part measured by the position sensor. In addition, the movement mechanism control unit determines the amount of movement of the holding mechanism by the movement mechanism, based on the position of the tip of the wire relative to the holding mechanism determined by the wire tip position calculation unit. Therefore, even if the wire has a bending tendency and is bent, the tip of the wire can be moved to an accurate position. As a result, brazing can be performed in an accurate position.

FIG. 1 is a front view of a brazing apparatus according to a first embodiment of the present disclosure. Hardware configuration diagram of a brazing device according to a first embodiment of the present disclosure. An enlarged view of region IIIA shown in FIG. 3B is a bottom view of the displacement sensor shown in FIG. FIG. 3B is a left side view of the displacement sensor shown in FIG. FIG. 1 is a block diagram of a control unit included in a brazing apparatus according to a first embodiment of the present disclosure. 1 is a flowchart of a brazing process performed by a control unit included in the brazing apparatus according to the first embodiment of the present disclosure. 1 is a flowchart of a brazing position correction process performed by a control unit included in the brazing apparatus according to the first embodiment of the present disclosure. FIG. 1 is a conceptual diagram of a graph obtained by plotting profile data measured by a displacement sensor included in the brazing apparatus according to the first embodiment of the present disclosure. FIG. 1 is a conceptual diagram of a wire position deviation amount calculated by a wire-tip-position calculation unit included in a control unit included in a brazing apparatus according to a first embodiment of the present disclosure. FIG. 1 is a perspective view of an object to be brazed by a brazing apparatus according to a first embodiment of the present disclosure; FIG. 13 is a perspective view of an object to be brazed in a modified example of the brazing process performed by the brazing apparatus according to the first embodiment of the present disclosure. 1 is a flowchart of a modified example of a brazing process performed by the brazing apparatus according to the first embodiment of the present disclosure. FIG. 11 is a block diagram of a control unit included in a brazing apparatus according to a second embodiment of the present disclosure. FIG. 13 is a front view of a length measuring sensor provided in the brazing apparatus according to the second embodiment of the present disclosure. FIG. 13 is a bottom view of a length measuring sensor provided in the brazing apparatus according to the second embodiment of the present disclosure. FIG. 13 is a left side view of a length measuring sensor provided in the brazing apparatus according to the second embodiment of the present disclosure. 11 is a flowchart of a wire length adjustment process performed by a control unit included in a brazing apparatus according to a third embodiment of the present disclosure. FIG. 13 is a bottom view of a nozzle illustrating a state of the wire at a stage where a wire length adjustment process performed by a control unit included in a brazing apparatus according to a third embodiment of the present disclosure is started. FIG. 13 is a bottom view of a nozzle in a state where the wire is being returned in a wire length adjustment process performed by a control unit included in the brazing apparatus according to the third embodiment of the present disclosure. FIG. 13 is a bottom view of a nozzle when a tip of the wire is in a light projecting portion of a displacement sensor as a result of the wire being fed out in a wire length adjustment process performed by a control unit included in a brazing apparatus according to a third embodiment of the present disclosure. FIG. 13 is a bottom view of the nozzle when the wire is adjusted to a target length in a wire length adjustment process performed by a control unit included in the brazing apparatus according to the third embodiment of the present disclosure. Hardware configuration diagram of a brazing device according to a fourth embodiment of the present disclosure. FIG. 13 is a front view of a photoelectric sensor included in the brazing apparatus according to the fourth embodiment of the present disclosure. FIG. 13 is a bottom view of a photoelectric sensor provided in the brazing apparatus according to the fourth embodiment of the present disclosure. FIG. 13 is a left side view of a photoelectric sensor included in the brazing apparatus according to the fourth embodiment of the present disclosure. 11 is a flowchart of a wire length adjustment process performed by a control unit included in a brazing apparatus according to a fourth embodiment of the present disclosure. FIG. 13 is a bottom view of a nozzle in a state where the wire is being returned in a wire length adjustment process performed by a control unit included in the brazing apparatus according to the fourth embodiment of the present disclosure. FIG. 13 is a bottom view of the nozzle when the tip of the wire hits the laser light projected by the photoelectric sensor as a result of the wire being fed out in the wire length adjustment process performed by the control unit included in the brazing apparatus according to the fourth embodiment of the present disclosure. FIG. 13 is a bottom view of the nozzle when the wire is adjusted to a target length in a wire length adjustment process performed by a control unit included in the brazing apparatus according to the fourth embodiment of the present disclosure.

Hereinafter, the brazing apparatus, the brazing apparatus control method, and the program according to the embodiments of the present disclosure will be described in detail with reference to the drawings. Note that in the drawings, the same or equivalent parts are denoted by the same reference numerals.

(Embodiment 1)
The brazing device according to the first embodiment is a device that performs brazing at a desired position by moving a nozzle from which a wire formed of brazing material protrudes at the tip side. In this brazing device, in order to perform brazing at an accurate position, a control unit corrects the moving position of the nozzle based on output data from a displacement sensor.

First, the configuration of the brazing apparatus will be described with reference to Figure 1. Next, the configuration for correcting the moving position of the nozzle, such as the control unit and the displacement sensor, will be described with reference to Figures 2, 3A-3C, and 4. Note that the wire formed from the brazing material is a member called a wire-shaped brazing material or a wire brazing material, but hereinafter it will be simply referred to as the wire.

Figure 1 is a front view of the brazing device according to embodiment 1. Note that in Figure 1, the electric wires extending from each component are omitted for ease of understanding.

As shown in FIG. 1, the brazing apparatus 1A includes a wire supply mechanism 10 that supplies wire 2, a nozzle 20 through which the wire 2 is inserted, and a moving mechanism 30 that moves the nozzle 20.

The wire supply mechanism 10 is a mechanism for feeding the wire 2 to the nozzle 20. In detail, the wire supply mechanism 10 has a pair of rollers 11, 12 that feed the wire 2.

Rollers 11 and 12 are arranged at a distance that allows wire 2 to pass through. Meanwhile, wire 2 is wound on reel 3. Wire 2 is pulled out from reel 3 and passed between rollers 11 and 12.

The rollers 11 and 12 are formed with grooves (not shown) for passing the wire 2 through. The rollers 11 and 12 clamp the wire 2 with the wire 2 passing through the grooves. The rollers 11 and 12 are then rotated in directions D1 and D2 by the motor 13. As a result, the rollers 11 and 12 send out the wire 2 towards the nozzle 20.

The nozzle 20 is a member that guides the wire 2. More specifically, the nozzle 20 is formed in a cylindrical shape that tapers toward the tip T2, and the wire 2 is inserted into the nozzle 20. The axis A1 of the nozzle 20 extends linearly. The wire supply mechanism 10 feeds the wire 2 into the nozzle 20 from the side opposite the tip T2. As a result, the wire 2 protrudes from the nozzle 20 on an extension of the axis A1 toward the tip T2. In this way, the nozzle 20 determines the direction in which the wire 2 is fed out.

On the other hand, the base of the nozzle 20 is held by a holder 21 formed in a columnar shape and fixed to a moving mechanism 30. The nozzle 20 moves together with the holder 21 as the holder 21 is moved by the moving mechanism 30.

The movement mechanism 30 is composed of a vertical articulated robot having an arm section capable of up-down, swiveling and forward-backward movement, and a hand section capable of rotating, twisting and bending. The holder 21 is fixed to the hand section. The movement mechanism 30 moves the holder 21 to the desired position by causing the arm section and hand section to perform the various movements described above. As a result, the nozzle 20 moves to the desired position.

In detail, the movement mechanism 30 assumes that the wire 2 protrudes from the tip T2 of the nozzle 20 by the target length L1, and moves the nozzle 20 to a position where the tip T1 of the wire 2 at that time abuts the brazing point of the target object. This is because if the nozzle 20 is moved to a position where the tip T2 abuts the brazing point, the wire 2 may become clogged at the tip T2 of the nozzle 20 when the wire supply mechanism 10 feeds out the wire 2.

Here, the target length L1 is a length that is set as a target to prevent clogging of the wire 2, and is a length that can be changed depending on various brazing conditions such as the diameter of the nozzle 20 and the material of the wire 2. Hereinafter, the target length L1 will be simply referred to as length L1.

By moving the nozzle 20 to the above position, the movement mechanism 30 moves the tip T2 of the nozzle 20 to a position a length L1 away from the brazing point. In this state, the brazing apparatus 1A causes the wire supply mechanism 10 to feed out the wire 2 to perform brazing. The brazing apparatus 1A also heats the brazing point using a heating mechanism not shown in FIG. 1. As a result, the tip T1 of the wire 2 abuts against the brazing point. The tip T1 also touches the heated brazing point and melts due to the heat. This causes the wire 2 to be supplied to the brazing point. The wire 2 also protrudes from the nozzle 20 by a length equal to the length L1, which is the target length from the tip T2 of the nozzle 20 to the brazing point.

However, as mentioned above, the wire 2 is wound around the reel 3, and as a result, is in a coil shape. Therefore, even when the wire 2 is unwound from the reel 3, the curling tendency remains, and the portion of the wire 2 protruding from the nozzle 20 may remain bent.

In addition, since the inner diameter of the nozzle 20 is larger than that of the wire 2, the wire 2 may become misaligned from the direction of the axis A1 of the nozzle 20 tube.

Furthermore, when the moving mechanism 30 moves the nozzle 20, the tension applied to the wire 2 changes between the wire supply mechanism 10 and the nozzle 20, which may result in the tip T1 of the wire 2 being shifted from its intended position.

In such a case, even if the moving mechanism 30 accurately moves the nozzle 20 to the above position, the tip T1 of the wire 2 will come off the brazing point.

Therefore, in order to prevent the tip T1 of the wire 2 from coming off the brazing point, the brazing apparatus 1A is equipped with, in addition to the above configuration, a displacement sensor 40A that measures the displacement of the wire 2. Furthermore, the brazing apparatus 1A is equipped with a wire feed amount detection sensor 50 that detects the amount of wire 2 fed to the nozzle 20 in order to control the amount of wire 2 fed from the wire supply mechanism 10, and a control unit 60A that adjusts the position to which the movement mechanism 30 moves the nozzle 20 based on the output data of the displacement sensor 40A, and controls the amount of wire 2 fed from the wire supply mechanism 10 based on the output data of the wire feed amount detection sensor 50.

Next, with reference to Figures 2, 3A-3C and 4, the configurations of the displacement sensor 40A, wire feed amount detection sensor 50 and control unit 60A will be described.

Figure 2 is a hardware configuration diagram of the brazing apparatus 1A. Figure 3A is an enlarged view of region IIIA shown in Figure 1. Figure 3B is a bottom view of the displacement sensor 40A shown in Figure 3A. Figure 3C is a left side view of the displacement sensor 40A. Figure 4 is a block diagram of the control unit 60A provided in the brazing apparatus 1A.

In addition, in Figures 3A to 3C, the nozzle 20 and wire 2 are shown to show the relative position of the displacement sensor 40A. Also, in Figures 3B and 3C, the holder 21 is omitted to facilitate understanding. Furthermore, in Figures 3A to 3C, the XY coordinates, which are the measurement coordinates of the displacement sensor 40A, are shown to facilitate understanding. In Figure 4, in addition to the control unit 60A, the displacement sensor 40A, the wire feed amount detection sensor 50, etc. are shown.

The displacement sensor 40A is provided to obtain data determining the inclination of the wire 2 from the axis A1 of the nozzle 20 shown in Figures 3A and 3B.

To explain in more detail, the tip T1 of the wire 2 is brought into contact with the brazing point as described above. The tip T1 of the wire 2 is heated and melted during brazing. For this reason, even if the wire supply mechanism 10 shown in FIG. 1 feeds out the wire 2 and causes the wire 2 to protrude from the nozzle 20 by a length L1, the tip T1 of the wire 2 is not necessarily located at a position that is the length L1 away from the nozzle 20, and may be shifted in the forward/backward direction. As a result, even if the displacement sensor 40A measures a position that is the length L1 away from the nozzle 20, there are cases in which the position of the tip T1 of the wire 2 cannot be measured.

Therefore, the brazing apparatus 1A measures the inclination of the wire 2 protruding from the nozzle 20 to the midpoint, and estimates the position of the tip T1 of the wire 2 from the inclination and the length of the wire 2 protruding from the nozzle 20. The displacement sensor 40A is provided to obtain position data for determining the inclination of the wire 2 to the midpoint.

Here, the intermediate portion of the wire 2 refers to the portion of the wire 2 between the tip T1 of the wire 2 and the tip T2 of the nozzle 20. In other words, the intermediate portion of the wire 2 refers to the portion of the wire 2 on the tip side of the portion held by the nozzle 20, excluding the tip.

In order to obtain the position data of the nozzle 20, the displacement sensor 40A uses a sensor called a profile sensor that measures the displacement to the target. In detail, the displacement sensor 40A irradiates the target with a band-shaped laser light 42 shown in Figures 3A-3C, receives the reflected light, and measures the displacement to the target by triangulation. In this way, the displacement sensor 40A measures the surface shape of the target, that is, the position of each part of the outer shape. More specifically, the displacement sensor 40A measures the Y-direction position of each part of the outer shape of the cross section of the two-dimensional coordinate system that the sensor has, that is, the Y-direction of the XY coordinate system, assuming that the target is cut in the X-direction perpendicular to the Y-direction.

It has been explained that the displacement sensor 40A measures the position of each part of the outer shape, but this is because the displacement sensor 40A measures the outer shape of the Y cross section discretely. In other words, this is because the displacement sensor 40A measures using a digital method that handles discrete numerical data.

The displacement sensor 40A is disposed in the radial direction of the nozzle 20 as shown in Fig. 3A and Fig. 3C. The displacement sensor 40A is held by the holder 21 as shown in Fig. 3A. The specific position of the displacement sensor 40A is a position where the light projecting unit 41 of the displacement sensor 40A is in front of the nozzle 20. The light projecting unit 41 is also a position where the laser light 42 is projected onto the middle part of the wire 2 protruding from the nozzle 20. The displacement sensor 40A directs the Y direction of the XY coordinate system of the sensor itself toward the direction D3 in which the nozzle 20 is located, and further directs the Y direction perpendicular to the direction D3 and the axis A1 of the nozzle 20. As a result, when the displacement sensor 40A receives a measurement start signal transmitted from the control unit 60A, it can measure the positions of each part of the outer shape of the surface that crosses the middle part of the wire 2 protruding from the nozzle 20. In this specification, the part of the wire 2 that the displacement sensor 40A measures that protrudes from the nozzle 20 will be referred to as the protruding part hereinafter. After measurement, the displacement sensor 40A transmits the measurement data to a control unit 60A shown in FIG.

On the other hand, as described above, the wire 2 is supplied to the brazing point by the tip T1 being heated and melted at the brazing point. The wire feed amount detection sensor 50 is provided to detect the amount of the wire 2 being fed.

1, the wire feed amount detection sensor 50 includes rollers 51 and 52 that sandwich the wire 2, and an encoder 53 attached to the roller 52. The rollers 51 and 52 rotate as the sandwiched wire 2 is fed out by the wire supply mechanism 10. When the roller 52 rotates, the encoder 53 measures the number of rotations. The wire feed amount detection sensor 50 transmits the number of rotations measured by the encoder 53 to the control unit 60A as data for calculating the feed amount of the wire 2. The method of calculating the feed amount of the wire 2 by the control unit 60A using the number of rotations measured by the encoder 53 will be described later.

2, the control unit 60A includes a computer having a CPU (Central Processing Unit) 61 and a memory 62 including a ROM (Read Only Memory) and a RAM (Random Access Memory), and an I/O port 65 for connecting the wire supply mechanism 10, the displacement sensor 40A, the moving mechanism 30, and the wire feed amount detection sensor 50, etc. The CPU 61 reads out programs stored in the ROM or storage device 63 into the RAM and executes them to perform various processes.

The control unit 60A, for example, executes the brazing position correction program 64 stored in the storage device 63 by the CPU 61. This performs the brazing position correction process. To perform the brazing position correction process, the control unit 60A includes processing blocks of a wire tip position calculation unit 610 and a movement mechanism control unit 620, which are configured as software, as shown in FIG.

The wire tip position calculation unit 610 calculates the position of the tip T1 of the wire 2 and the amount of positional deviation in order to correct the position when the moving mechanism 30 moves the nozzle 20 to the brazing work position, i.e., when the tip T2 of the nozzle 20 is moved to a position a length L1 away from the brazing point.

The detailed calculation contents will be described when explaining using the flow chart, but the above-mentioned target length L1 is stored in advance in the memory device 63. More specifically, the brazing apparatus 1A is equipped with an input device 80 consisting of a keyboard, numeric keypad, etc., into which the operator inputs the above-mentioned length L1, and the control unit 60A stores the length L1 input to the input device 80 in advance in the memory device 63. The wire tip position calculation unit 610 first reads out data on the length L1 of the wire 2 from the memory device 63. The wire tip position calculation unit 610 sets the read-out length L1 of the wire 2 as the length of the protruding portion of the wire 2.

Here, as described above, the movement mechanism 30 positions the tip T2 of the nozzle 20 at a position that is a length L1 away from the brazing point. Then, in this state, the wire supply mechanism 10 feeds out the wire 2, causing the wire 2 to come into contact with the heated object to be brazed. This causes the tip T2 of the wire 2 to melt due to the heat of the object to be brazed. Therefore, as long as normal brazing is repeated, the length of the protruding portion of the wire 2 is length L1 and remains at that length. Therefore, the wire tip position calculation unit 610 reads out length L1 from the storage device 63, and assuming that normal brazing is being performed, sets the read length L1 as the length of the protruding portion of the wire 2.

In addition, the wire tip position calculation unit 610 transmits a measurement start signal to the displacement sensor 40A to cause the displacement sensor 40A to measure the positions of each part of the outer shape on a plane crossing the middle part of the protrusion of the wire 2. The wire tip position calculation unit 610 then obtains the measurement results from the displacement sensor 40A.

The wire tip position calculation unit 610 calculates the position of the tip T1 of the wire 2 relative to the nozzle 20 based on the data of the length L1 of the wire 2 read from the storage device 63 and the position data of each part of the outer shape obtained from the displacement sensor 40A. In detail, the storage device 63 stores the position data of the displacement sensor 40A relative to the tip of the nozzle 20 and the axis A1, and the wire tip position calculation unit 610 calculates the inclination of the wire 2 relative to the axis A1 of the nozzle 20 shown in Figures 3A and 3B from the position data of the displacement sensor 40A and the position data of each part of the outer shape of the wire 2 obtained from the displacement sensor 40A. Then, the wire tip position calculation unit 610 assumes that the wire 2 extends linearly in the direction of the calculated inclination, and calculates the position of the tip T1 of the wire 2 relative to the tip T2 of the nozzle 20 from the calculated direction of the inclination and the length L1 treated as the length of the protruding part of the wire 2.

Furthermore, the wire tip position calculation unit 610 calculates how much the tip of the wire 2 in an ideal state protruding linearly from the nozzle 20 is shifted from the calculated position of the tip T1 of the wire 2. The wire tip position calculation unit 610 transmits the calculated amount of positional deviation to the movement mechanism control unit 620 shown in FIG.

The calculated position deviation amount is the deviation amount expressed in the up/down, left/right, and front/back coordinates when the nozzle 20 is moved by the movement mechanism 30.

The movement mechanism control unit 620 corrects the amount of movement when the movement mechanism 30 moves the nozzle 20 based on the amount of positional deviation received from the wire tip position calculation unit 610. The movement mechanism control unit 620 transmits the corrected amount of movement to the movement mechanism 30.

The movement mechanism 30 changes the amount of movement when moving the nozzle 20. In other words, the movement mechanism 30 sets the destination of the nozzle 20 to the corrected amount of movement. As a result, when the movement mechanism 30 moves the nozzle 20, the tip T1 of the wire 2 protruding from the nozzle 20 accurately abuts the brazing point of the object. As a result, accurate brazing is possible.

Note that each of the above-mentioned processing blocks corresponds to a case where the CPU 61 executes the brazing position correction program 64 stored in the storage device 63, but in addition to the brazing position correction program 64, the CPU 61 executes various programs including the brazing program 66 stored in the storage device 63. As a result, the control unit 60A performs various processes.

For example, the control unit 60A executes the brazing program 66 to perform the brazing process. As a result, the control unit 60A controls the amount of wire 2 supplied from the wire supply mechanism 10 during brazing based on the output data of the wire feed amount detection sensor 50. In detail, the storage device 63 stores in advance the specified value data of the amount of wire 2 fed out during brazing and the outer diameter value data of the roller 52. The control unit 60A reads out the specified value and the outer diameter value data, calculates the amount of wire 2 fed out from the number of rotations of the roller 52, which is the output data of the wire feed amount detection sensor 50, and the read outer diameter value of the roller 52, and compares the calculated amount of wire 2 with the read specified value to control the number of rotations of the motor 13 of the wire supply mechanism 10. In this way, the control unit 60A controls the amount of wire 2 fed out.

In addition, when the motor 13 is a servo motor, the encoder 53 provided in the servo motor is used instead of the wire feed amount detection sensor 50, and the wire feed amount detection sensor 50 may be omitted. In that case, the control unit 60A treats the rotation speed detected by the encoder 53 as the rotation speed of the rollers 11, 12, and calculates the feed amount of the wire 2 from the rotation speed and the outer diameter value of the rollers 11, 12.

Next, the brazing process performed by the control unit 60A will be described with reference to Figures 5 to 9. In the following explanation, the brazing process will be described using an example in which the brazing apparatus 1A brazes only one location at a fixed length L1. It is assumed that the brazing apparatus 1A is provided with a start button (not shown). It is also assumed that the length L1 is input to the input device 80, and as a result, data on the length L1 is pre-stored in the memory device 63. It is also assumed that the operator adjusts the length of the protruding portion of the wire 2 to length L1, and the brazing process is performed after this adjustment.

Figure 5 is a flowchart of the brazing process performed by the control unit 60A. Figure 6 is a flowchart of the brazing position correction process performed by the control unit 60A. Figure 7 is a conceptual diagram of a graph when profile data measured by the displacement sensor 40A is plotted. Figure 8 is a conceptual diagram of the positional deviation amount of the wire 2 calculated by the wire tip position calculation unit 610 of the control unit 60A. Figure 9 is an oblique view of an object to be brazed by the brazing apparatus 1A.

8, for ease of understanding, a projected wire image 5 obtained by projecting the wire 2 onto the XY plane is shown, and the tip coordinates Pt ₀ of the ideal wire 4 are also shown.

First, when the object to be brazed is set in a predetermined position, the operator presses a start button (not shown) on the brazing apparatus 1A. This causes the brazing program 66 stored in the storage device 63 shown in Figure 2 to be executed by the CPU 61 provided in the control unit 60A, and the brazing process flow begins.

When the brazing process flow is started, first, the control unit 60A moves the nozzle 20 to the standby position as shown in FIG. 5 (step S1). The brazing apparatus 1A is equipped with a heating mechanism 70 shown in FIG. 4 to heat the object to be brazed. Here, the heating mechanism 70 is, for example, a gas burner, a high-frequency induction heating device, or a laser device. The standby position is a position provided to prevent the wire 2 from being affected by heat from the heating mechanism 70, and is provided at a location away from the heating mechanism 70. In step S1, the control unit 60A causes the moving mechanism 30 to perform an operation to move the nozzle 20 to the standby position, regardless of whether the nozzle 20 is in the standby position or not.

Next, the control unit 60A performs a brazing position correction process (step S2). In detail, when step S1 is completed, the control unit 60A causes the CPU 61 to execute the brazing position correction program 64 stored in the storage device 63. This starts the flow of the brazing position correction process shown in FIG. 6.

When the brazing position correction process flow is started, first, as shown in Figure 6, the wire tip position calculation unit 610 obtains the length L of the protruding portion of the wire 2 protruding from the nozzle 20 (step S21).

In detail, as described above, the length L1 of the wire 2 is stored in the storage device 63. The wire tip position calculation unit 610 reads the data of the length L1 from the storage device 63, and sets the read data of the length L1 as the length L of the protruding portion of the wire 2. In this way, the wire tip position calculation unit 610 obtains the length L of the protruding portion of the wire 2.

When the wire-tip-position calculation unit 610 acquires the length L of the protruding portion of the wire 2, it sends a measurement start signal to the displacement sensor 40A to cause the displacement sensor 40A to measure the positions of each part of the outer shape on a plane crossing the middle part of the protruding portion of the wire 2. In other words, the wire-tip-position calculation unit 610 causes the displacement sensor 40A to measure the profile of the middle part of the protruding portion of the wire 2. The wire-tip-position calculation unit 610 acquires the profile data from the displacement sensor 40A (step S22).

Next, the wire tip position calculation unit 610 calculates the position of the tip T1 of the wire 2 (step S23).

In detail, the wire tip position calculation unit 610 calculates the position of the tip T1 of the wire 2 using the profile data acquired from the displacement sensor 40A. An example of the profile data 400 acquired from the displacement sensor 40A is shown in FIG.

In addition to the profile data 400 measured by the displacement sensor 40A, Figure 7 also shows profile data 410 of an ideal wire 4 in which the wire 2 extends linearly forward from the nozzle 20. The profile data 400 and 410 are data obtained by measuring the positions of each part of the outer shape of the wire 2 in the X-direction cross section by the displacement sensor 40A from the +Y side shown in Figure 7. Therefore, the profile data 400 and 410 have edges 401, 402, 411, and 412 perpendicular to the X direction.

The wire-tip-position calculation unit 610 determines the point ( _Xw , _Yw ) halfway between the edges 401 and 402 that has the largest Y value as the representative point 403 of the wire 2. Meanwhile, the storage device 63 pre-stores coordinate (Xn, Yn) data of the representative point 413 of the ideal wire 4. The wire-tip-position calculation unit 610 reads out the coordinate ( _Xn , _Yn ) data of the representative point 413 of the ideal wire 4, and determines the relative coordinate ( _ΔX , _ΔY ) of the representative point 403 of the measured profile data 400 with respect to the representative point 413 of the ideal wire 4, from the read coordinate ( _Xn , _Yn ) data and the coordinate (Xw, Yw) data of the representative point 403 obtained from the profile data 400 measured by the displacement sensor 40A. In this way, the wire tip position calculation unit 610 obtains the XY coordinates of the wire coordinate Pw of the actual midpoint of the protrusion of the wire 2 when the tip coordinate Pn of the nozzle 20 shown in FIG. 8 is set as the origin (0,0,0).

The memory device 63 also stores data on the distance in the direction of the tip T2 from the tip T2 of the nozzle 20 shown in Figures 3A and 3B to the light projector 41 of the displacement sensor 40A, i.e., the distance A shown in Figure 8. The wire tip position calculation unit 610 reads out the data on the distance A from the memory device 63, and sets the read distance A as the Z coordinate of the wire coordinate Pw.

As a result of the above, the wire tip position calculation unit 610 obtains all the values of the XYZ coordinates of the wire coordinate Pw.

The wire-tip-position calculation unit 610 obtains the inclination of the actual wire 2 with respect to the ideal wire 4 from the XYZ coordinates (ΔX, ΔY, A) of the wire coordinate Pw, and further assumes that the wire 2 extends linearly with that inclination and extends from the tip T1 of the nozzle 20 by the length L of the protruding portion of the wire 2 obtained in step S21, and obtains the tip coordinates Pt ₁ (ΔX ₁ , ΔY ₁ , ΔZ ₁ ) of the wire 2 shown in Fig. 8. In detail, the wire-tip-position calculation unit 610 applies the XYZ coordinates (ΔX, ΔY, A) of the wire coordinate Pw and the length L of the protruding portion of the wire 2 to Equations 1 to 5 to obtain the tip coordinates Pt ₁ (ΔX ₁ , ΔY ₁ , ΔZ ₁ ). In this way, the wire-tip-position calculation unit 610 calculates the position of the tip T1 of the wire 2 in step S23.

Returning to Fig. 6, after the calculation of the position of the tip T1 of the wire 2 in step S23, the wire-tip-position calculation unit 610 calculates the amount of positional deviation of the tip T1 of the wire 2 (step S24). In detail, the wire-tip-position calculation unit 610 sets the Z coordinate of the tip coordinate _Pt0 of the ideal wire 4 shown in Fig. 8 as the length L of the protruding portion of the wire 2 obtained in step S21, and determines the relative position of the tip coordinate _Pt0 (0,0,L) of the ideal wire 4 in this case with respect to the tip coordinate _Pt1 ( _ΔX1 , _ΔY1 , _ΔZ1 ) of the wire 2. The movement mechanism control unit 620 then sets the determined relative position as the correction amount.

Next, the control unit 60A determines whether or not it has received a wire supply signal transmitted from the heating mechanism 70 shown in FIG. 4 (step S25). In detail, although not shown, the heating mechanism 70 heats the brazing point of the pipe, which is the object to be brazed, and transmits the wire supply signal when a certain time has passed since heating. Alternatively, the heating mechanism 70 transmits the wire supply signal when the temperature sensor provided in the heating mechanism 70 exceeds a certain temperature. In step S25 shown in FIG. 6, the control unit 60A determines whether or not it has received this wire supply signal.

When the movement mechanism control unit 620 of the control unit 60A determines that the wire supply signal has been received (Yes in step S25), it transmits a correction amount for the movement of the nozzle 20 to the movement mechanism 30 (step S26). The movement mechanism 30 receives the correction amount and corrects the movement amount when moving the nozzle 20.

For example, if the object to be brazed is a structure comprising a pipe 102 having an expanded portion 101 and a pipe 103 inserted into the expanded portion 101, as shown in Figure 9, the designed brazing point 104 is adjacent to the expanded portion 101. If the portion of the wire 2 protruding from the nozzle 20 is bent, the tip T1 of the wire 2 will be misaligned from the brazing point 104 when the nozzle 20 is moved. The above correction amount is data for eliminating the misalignment between the brazing point 104 and the actual tip T1 of the wire 2.

Although not shown, the movement mechanism 30 uses this correction amount to correct the movement amount when moving the nozzle 20. This enables the movement mechanism 30 to accurately move the tip T1 of the wire 2 to the brazing point 104 shown in Figure 9. The movement mechanism 30 moves the nozzle 20 by the corrected movement amount to position the nozzle 20 at the brazing work position. When the movement is completed, the movement mechanism 30 sends a movement completion signal to the control unit 60A.

Returning to FIG. 6, if the control unit 60A determines that the wire supply signal has not been received (No in step S25), it returns to before step S25 and repeats step S25 until it determines that the wire supply signal has been received.

After transmitting the correction amount in step S26, the control unit 60A ends the brazing position correction process. Then, the process returns to the brazing process flow shown in FIG. 5.

Returning to Fig. 5, after the brazing position correction process in step S2, when a certain time has elapsed or when a movement completion signal has been received, the control unit 60A starts feeding the wire 2 (step S3). In detail, the control unit 60A instructs the wire supply mechanism 10 to feed the wire 2 and drives the motor 13 to feed the wire 2.

As described above, the storage device 63 stores the specified value of the feed amount of the wire 2 fed in one brazing and the outer diameter value of the roller 52. After step S3, the control unit 60A reads out this specified value and the outer diameter value of the roller 52, and receives data on the number of rotations transmitted by the wire feed amount detection sensor 50, and calculates the feed amount of the wire 2 from the number of rotations and the read outer diameter value of the roller 52. The control unit 60A then determines whether the calculated feed amount of the wire 2 exceeds the read specified value (step S4).

If the control unit 60A determines that the specified value has been exceeded (Yes in step S4), it stops the feeding of the wire 2 (step S5). That is, the control unit 60A stops the motor 13 of the wire supply mechanism 10 to stop the feeding of the wire 2. As a result, the control unit 60A stops the supply of solder to the brazing point.

On the other hand, if the control unit 60A determines that the amount of wire 2 discharged does not exceed the specified value (No in step S4), the control unit 60A returns to before step S4 and performs step S4 again after a certain period of time has elapsed. As a result, the control unit 60A repeats step S4 until the amount of wire 2 discharged exceeds the specified value.

After the control unit 60A stops the feeding of the wire 2 in step S5, it then returns the nozzle 20 to the standby position (step S6).

The brazing process is completed through the above steps. After step S6, the control unit 60A ends the brazing process.

Note that step S21 described using FIG. 6 is an example of a wire length calculation step as defined in the present disclosure. Steps S23 and S24 are also examples of a wire tip position calculation step as defined in the present disclosure. Step S26 is an example of a movement mechanism control step as defined in the present disclosure.

Furthermore, the above nozzle 20 is an example of a holding mechanism for holding the portion of the wire 2 rearward of the tip T1 as defined in the present disclosure.

As described above, in the brazing apparatus 1A according to the first embodiment, the wire tip position calculation unit 610 calculates the amount of positional deviation of the actual tip T1 of the wire 2 from the tip T1 of the ideal wire 4 in a state where it protrudes linearly from the nozzle 20, based on the length L1 of the wire 2 and the profile of the wire 2 of the displacement sensor 40A. Then, the movement mechanism control unit 620 corrects the amount of movement of the nozzle 20 by the movement mechanism 30 based on the amount of positional deviation. Therefore, even if the wire 2 has a tendency to bend, that is, even if the wire 2 is bent, the tip T1 of the wire 2 can be moved to an accurate position. As a result, the brazing apparatus 1A can perform brazing at an accurate position.

In addition, in the brazing apparatus 1A, the wire feed amount detection sensor 50 detects the number of rotations of the roller 52 that rotates as the wire 2 is fed, and the control unit 60A controls the amount of wire 2 supplied from the wire supply mechanism 10 based on the number of rotations of the roller 52 detected. Therefore, the brazing apparatus 1A can not only braze at an accurate position, but also supply an accurate amount of brazing material to perform brazing. The brazing apparatus 1A can also automate brazing.

(Variation 1)
In the first embodiment, the wire-tip-position calculation unit 610 calculates the position and the amount of positional deviation of the tip T1 of the wire 2, assuming that the wire 2 extends in the same manner as an ideal wire 4 extending linearly from the nozzle 20. However, the wire-tip-position calculation unit 610 is not limited to this.

The wire tip position calculation unit 610 may calculate the position and positional deviation amount of the tip T1 of the wire 2, assuming that the wire 2 extends from the nozzle 20 in a specific shape. For example, the wire tip position calculation unit 610 may calculate the position and positional deviation amount of the tip T1 of the wire 2, assuming that the wire 2 extends from the nozzle 20 in a curved shape represented by a parabola, a quadratic function, or the like.

(Variation 2)
In addition, the brazing flow described in the first embodiment is a process in which the brazing apparatus 1A brazes only one portion. However, the brazing process is not limited to this. The brazing process may be a process in which the brazing apparatus 1A brazes a plurality of portions.

For example, the control unit 60A may perform the brazing position correction process described using Figure 6 each time brazing is performed.

Figure 10 is a perspective view of an object to be brazed in a modified example of the brazing process performed by the brazing apparatus 1A. Figure 11 is a flowchart of a modified example of the brazing process performed by the brazing apparatus 1A.

10 , when the objects to be brazed are, for example, pipes 105 and 106, brazing may be performed along the joint portion. In this case, in the brazing apparatus 1A, a plurality of discrete points P ₁ , P ₂ , P ₃ ... with which the tip T1 of the wire 2 will come into contact as the movement mechanism 30 moves the nozzle 20 may be set as brazing points. The movement mechanism 30 may move the nozzle 20 in sequence with the tip T1 of the wire 2 coming into contact with the plurality of points P ₁ , P ₂ , P ₃ ....

In this case, the control unit 60A may execute the brazing position correction process described with reference to FIG. 6 for each of the points P ₁ , P ₂ , P ₃ . . .

Although not shown, for example, in the brazing process described in Fig. 5, the heating mechanism 70 transmits a wire supply signal when the temperature reaches a state where brazing is possible, and this supply signal may be transmitted each time a plurality of discrete locations _P1 , _P2 , _P3 , ... are brazed. In the brazing process, as shown in Fig. 11, it may be determined whether or not a wire supply signal has been received between steps S1 and S2 described using Fig. 5 (step S7). In this case, in the brazing position correction process in step S2, it may be omitted to determine whether or not a wire supply signal has been received in step S25 shown in Fig. 6.

Furthermore, in the brazing process, as shown in FIG. 11, between steps S5 and S6, it is preferable to determine whether there are any more brazing points (step S8). In this case, if the control unit 60A determines that there are more brazing points (No in step S8), it may return to step S7 and wait for a wire supply signal indicating the timing of the next brazing. Also, if the control unit 60A determines that there are no more brazing points (Yes in step S8), it may proceed to step S6. Then, the control unit 60A may end the flow after step S6.

In this type of process, as in embodiment 1, the brazing apparatus 1A can move the tip T1 of the wire 2 to a precise position and perform brazing at the precise position.

(Embodiment 2)
In the first embodiment, the displacement sensor 40A measures so-called profile data. However, the brazing apparatus 1A is not limited to this. The brazing apparatus 1A may be any position sensor that measures the positions of each portion of the outer shape of the wire 2.

The brazing apparatus 1B of embodiment 2 is equipped with length measurement sensors 40B and 40C which function as position sensors.

Figure 12 is a block diagram of a control unit 60B provided in the brazing apparatus 1B according to embodiment 2. Figure 13A is a front view of length measurement sensors 40B, 40C provided in the brazing apparatus 1B according to embodiment 2. Figure 13B is a bottom view of length measurement sensors 40B, 40C. Figure 13C is a left side view of length measurement sensors 40B, 40C.

In Figures 13A-13C, the X and Y coordinates are displayed near the length measuring sensors 40B and 40C to indicate which length measuring sensor 40B or 40C measures the X or Y coordinate of the measurement coordinates of the displacement sensor 40A described in embodiment 1. Also, in Figures 13A and 13B, the light receiving units 46 and 44 are omitted to make it easier to understand the positional relationship with the wire 2.

As shown in FIG. 12, the brazing apparatus 1B is equipped with length measuring sensors 40B, 40C that transmit measurement results to the control unit 60B.

13A-13C, the length measuring sensors 40B, 40C include light emitting units 43, 45 that emit band-shaped laser light 42 toward the object to be measured, and light receiving units 44, 46 that face the light emitting units 43, 45 and have the object to be measured located between the light emitting units 43, 45. The length measuring sensors 40B, 40C measure the width and position of the object to be measured in the band direction of the laser light 42 by having the light receiving units 44, 46 measure the light amount distribution in the band direction of the band-shaped laser light 42, part of which is blocked by the object to be measured.

As shown in Figures 13A-13C, the light-emitting units 43, 45 each emit a strip of laser light 42 toward the protruding portion of the wire 2 protruding from the nozzle 20 from two mutually perpendicular directions on a plane perpendicular to the cylindrical axis A1 of the nozzle 20. The light-receiving units 44, 46 then receive the laser light 42 at a position where the protruding portion of the wire 2 is sandwiched between them and the light-emitting units 43, 45. As a result, the length measurement sensors 40B, 40C measure the width and position of the protruding portion of the wire 2 when viewed from these two directions.

By defining the above two directions as the X and Y directions, length measurement sensors 40B and 40C measure the width and position of the protrusion of wire 2 in the X and Y coordinates of the measurement coordinates of displacement sensor 40A described in embodiment 1. In this way, length measurement sensors 40B and 40C obtain the X coordinates of the +X end and -X end of the protrusion of wire 2, and the Y coordinates of the +Y end and -Y end of the protrusion. Length measurement sensors 40B and 40C transmit these X and Y coordinates to control unit 60B.

The control unit 60B shown in Fig. 12 includes a wire-tip-position calculation unit 610, which is not shown in Fig. 12. The wire-tip-position calculation unit 610 uses the X coordinates of the +X end and -X end of the protrusion of the wire 2 measured by the length measurement sensor 40B and the Y coordinates of the +Y end and -Y end of the protrusion of the wire 2 measured by the length measurement sensor 40B instead of the profile data of the displacement sensor 40A described in the first embodiment, to determine the XY coordinates of the center line of the protrusion of the wire 2.

Meanwhile, the XY coordinates of the center line of the ideal wire 4 are stored in advance in the memory device 63. The wire tip position calculation unit 610 reads out the XY coordinates of the center line of the ideal wire 4 from the memory device 63, and determines the relative coordinates (ΔX, ΔY) of the center line of the protruding part of the wire 2 based on the XY coordinates.

The wire tip position calculation unit 610 uses the determined relative coordinates (ΔX, ΔY) to calculate the position of the tip T1 of the wire 2 in the same manner as in embodiment 1, and further determines the amount of positional deviation. As in embodiment 1, the movement mechanism control unit 620 provided in the control unit 60B corrects the amount of movement when the movement mechanism 30 moves the nozzle 20 based on the amount of positional deviation. As a result, the brazing apparatus 1B is capable of accurate brazing, just like the brazing apparatus 1A of embodiment 1.

The two orthogonal directions on a plane perpendicular to the axis A1 of the nozzle 20 described above, specifically the X direction and the Y direction, are examples of the first direction and the second direction as defined in this disclosure. Furthermore, the length measuring sensors 40B and 40C are examples of the first length measuring sensor and the second length measuring sensor as defined in this disclosure. The protruding portion of the wire 2 is an example of a portion protruding from the nozzle 20 as defined in this disclosure.

As described above, in the brazing apparatus 1B according to the second embodiment, the length measurement sensor 40B measures the position of the outer end of the protruding portion of the wire 2 protruding from the nozzle 20 when viewed from the X direction perpendicular to the axis A1 of the nozzle 20. In addition, the length measurement sensor 40C measures the position of the outer end of the protruding portion of the wire 2 when viewed from the Y direction perpendicular to the axis A1 and the X direction. Therefore, the brazing apparatus 1B can accurately measure the position of the protruding portion of the wire 2 and accurately grasp its positional deviation, similar to the first embodiment.

The length measuring sensors 40B and 40C have a simpler structure and are less expensive than the displacement sensor 40A described in embodiment 1, thereby reducing the brazing costs.

(Embodiment 3)
In the brazing apparatuses 1A and 1B according to the first and second embodiments, it is assumed that the moving mechanism 30 moves the tip T2 of the nozzle 20 to a position away from the brazing point by a target length L1, and normal brazing is performed in that state. As a result, the control units 60A and 60B perform the brazing position correction process assuming that the length L of the protruding portion of the wire 2 is length L1. However, the brazing apparatuses 1A and 1B are not limited to this. In the brazing apparatuses 1A and 1B, the wire supply mechanism 10 may determine the length L of the protruding portion of the wire 2.

In the brazing apparatus 1A according to embodiment 3, the control unit 60A controls the movement mechanism 30 to adjust the length L of the protruding portion of the wire 2. Below, the brazing apparatus 1A according to embodiment 3 will be described with reference to Figures 14 and 15A-15D. Note that in embodiment 3, since the hardware configuration of the brazing apparatus 1A is the same as in embodiment 1, the description will be omitted and the flow of adjusting the length of the wire 2 performed by the control unit 60A provided in the brazing apparatus 1A will be described. Also, the same symbols will be used for the same configuration as in embodiment 1.

Figure 14 is a flowchart of the wire 2 length adjustment process performed by the control unit 60A of the brazing apparatus 1A according to embodiment 3. Figure 15A is a bottom view of the nozzle 20 showing the state of the wire 2 at the stage of starting the wire 2 length adjustment process. Figure 15B is a bottom view of the nozzle 20 in a state in which the wire 2 is returned in the wire 2 length adjustment process. Figure 15C is a bottom view of the nozzle 20 when the tip T1 of the wire 2 is in the light projecting portion 41 of the displacement sensor 40A as a result of the wire 2 being sent out in the wire 2 length adjustment process. Figure 15D is a bottom view of the nozzle 20 when the wire 2 is adjusted to length L1 in the wire 2 length adjustment process.

First, when performing the first brazing with the brazing apparatus 1A, the operator of the brazing apparatus 1A passes the wire 2 through the nozzle 20. At this time, as shown in FIG. 15A, the operator positions the tip T1 of the wire 2 further forward than the light projector 41 of the displacement sensor 40A. Then, when the object to be brazed is set in a predetermined position, the operator presses the start button (not shown) described in embodiment 1. This causes the control unit 60A to start the brazing process flow described in embodiment 1.

Or, when the second or subsequent brazing is performed with the brazing apparatus 1A, the brazing process and the wire 2 length adjustment process described below are performed in the first brazing, so the tip T1 of the wire 2 is usually located further forward than the light projector 41 of the displacement sensor 40A. In this case, the position adjustment of the wire 2 is not performed by the operator as described above, and the start button is pressed after the object to be brazed is set. This causes the control unit 60A to start the brazing process flow.

In the brazing process, although not shown, the control unit 60A first performs step S1 described in embodiment 1. Next, the control unit 60A performs the length adjustment process of the wire 2 shown in FIG.

14, in the process of adjusting the length of the wire 2, the control unit 60A first rotates the rollers 11 and 12 of the wire supply mechanism 10 in the reverse direction to return the wire 2 to its initial state of being retracted toward the nozzle 20 (step S31). In the first embodiment, it was explained that the rollers 11 and 12 rotate in the directions D1 and D2 to feed the wire 2 from the nozzle 20, but the rotation of the rollers 11 and 12 in the direction opposite to the directions D1 and D2 is the reverse rotation of the rollers 11 and 12. In contrast, the rotation of the rollers 11 and 12 in the directions D1 and D2 is the forward rotation of the rollers 11 and 12. In step S31, the rollers 11 and 12 rotate in the reverse direction to move the tip T1 of the wire 2 toward the nozzle 20, as shown in FIG. 15B.

Next, the control unit 60A acquires the output of the displacement sensor 40A while the rollers 11 and 12 are still rotating in reverse. The control unit 60A then determines whether the wire 2 has been detected by the displacement sensor 40A (step S32). As described in the first embodiment using the profile data 400 and 410 shown in FIG. 7, when the displacement sensor 40A detects the wire 2, a Y value of a certain magnitude is detected. The control unit 60A acquires the profile data 400 from the displacement sensor 40A and determines whether the profile data 400 includes a Y value greater than the threshold value. This allows the determination of step S32 shown in FIG. 14 to be performed.

When the control unit 60A determines that the wire 2 has been detected by the displacement sensor 40A (Yes in step S32), the control unit 60A returns to before step S32 and performs step S32 again after a certain period of time has elapsed. As a result, the control unit 60A repeats step S32 until the wire 2 is no longer detected by the displacement sensor 40A.

On the other hand, when the control unit 60A determines that the wire 2 is not detected by the displacement sensor 40A (No in step S32), it determines that the wire 2 has retracted toward the nozzle 20 and returned to its initial state. In this case, the control unit 60A rotates the rollers 11 and 12 of the wire supply mechanism 10 in the forward direction to extend the wire 2 to the light projecting unit 41 of the displacement sensor 40A (step S33). During the forward rotation of the rollers 11 and 12, it is desirable that the rotation speed is slower than during reverse rotation in order to accurately determine the position of the tip T1 of the wire 2.

The control unit 60A acquires the output of the displacement sensor 40A while the rollers 11 and 12 are rotated in the forward direction. The control unit 60A then determines whether the wire 2 is detected by the displacement sensor 40A (step S34).

If the control unit 60A determines that the wire 2 has not been detected by the displacement sensor 40A (No in step S34), the control unit 60A returns to before step S34 and performs step S34 again. As a result, the control unit 60A repeats step S34 until the wire 2 is detected by the displacement sensor 40A.

On the other hand, when the control unit 60A determines that the wire 2 has been detected by the displacement sensor 40A (Yes in step S34), it determines that the tip T1 of the wire 2 has reached the light projector 41 of the displacement sensor 40A and is in a position where the tip T1 of the wire 2 overlaps with the light projector 41 as shown in Fig. 15C. In this case, the control unit 60A uses the position of the tip T1 of the wire 2 at this time as a reference, and stops the rollers 11 and 12 of the wire supply mechanism 10 as shown in Fig. 14 (step S35).

Next, the control unit 60A acquires profile data from the displacement sensor 40A while the rollers 11 and 12 are stopped (step S36). Furthermore, the control unit 60A uses the acquired profile data to calculate the number of rotations of the rollers 51 and 52 of the wire feed amount detection sensor 50 that will be detected until the tip T1 of the wire 2 is moved to the target position (step S37).

In detail, the control unit 60A obtains the X coordinate of the X-direction center of the tip T1 of the wire 2 shown in FIG. 15C from the acquired profile data. Meanwhile, the storage device 63 described in the first embodiment stores in advance the distance L2 from the tip T2 of the nozzle 20 shown in FIG. 15C to the light projecting unit 41 of the displacement sensor 40A. The control unit 60A reads out the value of the distance L2 from the storage device 63, and calculates the distance L3 from the tip T2 of the nozzle 20 shown in FIG. 15C to the tip T1 of the wire 2 using the read-out value of the distance L2 and the obtained value of the X coordinate. At this time, the control unit 60A may calculate the distance L3 assuming that the wire 2 extends linearly. In addition, when it is known that the wire 2 is bent in a specific shape, for example, when the wire 2 is curved such as an arc, a parabola, or a quadratic curve, the control unit 60A may calculate the distance L3 by approximating the shape.

In addition, the outside diameter values and the target length L1 of the rollers 51 and 52 are stored in advance in the storage device 63. The control unit 60A reads out the outside diameter values and length L1 of the rollers 51 and 52 from the storage device 63, and divides the difference between the read length L1 and the calculated distance L3 by the value of the outer periphery length of the rollers 51 and 52 calculated from the read outside diameter values of the rollers 51 and 52. In this way, the control unit 60A calculates the number of rotations that the rollers 51 and 52 will have to rotate before the tip T1 of the wire 2 shown in FIG. 15D moves and the length of the protruding portion of the wire 2 becomes length L1.

Returning to Fig. 14, when the control unit 60A calculates the number of rotations of the rollers 51 and 52, it resets the encoder 53 of the wire feed amount detection sensor 50 in order to actually measure the number of rotations of the rollers 51 and 52 (step S38). That is, the measurement value of the encoder 53 is reset to 0, making it possible to measure a new number of rotations.

Next, the control unit 60A rotates the rollers 11 and 12 of the wire supply mechanism 10 in the forward direction to set the length of the protruding portion of the wire 2 to length L1 (step S39). At this time, it is desirable for the control unit 60A to rotate the rollers 11 and 12 in the forward direction at a slow rotation speed, as in step S33.

With the rollers 11 and 12 rotating in the forward direction, the control unit 60A acquires the number of rotations measured by the encoder 53 from the wire feed amount detection sensor 50. Then, the control unit 60A determines whether the number of rotations measured by the encoder 53 exceeds the number of rotations calculated in step S37 (step S40).

If the control unit 60A determines that the number of rotations measured by the encoder 53 does not exceed the number of rotations calculated in step S37 (No in step S40), the control unit 60A returns to before step S40 and performs step S40 again. As a result, the control unit 60A repeats step S40 until the protruding portion of the wire 2 reaches the length L1 due to the forward rotation of the rollers 11 and 12.

On the other hand, if the control unit 60A determines that the number of rotations measured by the encoder 53 exceeds the number of rotations calculated in step S37 (Yes in step S40), it determines that the protruding portion of the wire 2 has reached length L1. In this case, the control unit 60A stops the rollers 11 and 12 of the wire supply mechanism 10 (step S41). Then, the control unit 60A ends the length adjustment process of the wire 2.

When the control unit 60A finishes the length adjustment process of the wire 2, it returns to the brazing process described in embodiment 1 (not shown). Then, the control unit 60A performs the steps of the brazing process from step S2 onwards, that is, the steps from the brazing position correction process of step S2 to the process of returning the nozzle 20 to the standby position of step S6. This causes the control unit 60A to complete the brazing process.

The control unit 60A is also referred to as a feed amount calculation unit because it calculates the feed amount of the wire 2 from the wire supply mechanism 10. The control unit 60A is an example of a feed amount calculation unit as defined in the present disclosure.

As described above, in the brazing apparatus 1A according to embodiment 3, the control unit 60A performs a length adjustment process for the wire 2 before performing the brazing position correction process described in embodiment 1. This allows the brazing apparatus 1A to move the tip T1 of the wire 2 to a more accurate position. As a result, the brazing apparatus 1A can perform brazing at a more accurate position.

(Embodiment 4)
In the brazing apparatus 1A according to the third embodiment, the control unit 60A uses the displacement sensor 40A to adjust the length of the wire 2. However, the control unit 60A is not limited to this. The brazing apparatus 1A may include a wire detection sensor that detects whether the tip T1 of the wire 2 is at a specific position on the side of the nozzle 20 from which the wire 2 protrudes. In this case, when the wire detection sensor detects the tip T1 of the wire 2, the control unit 60A may perform the length adjustment process of the wire 2 based on the relative position of the specific position with respect to the nozzle 20 and the length L1, which is a target value.

The brazing apparatus 1D according to the fourth embodiment includes a photoelectric sensor 40D, and a control unit 60D adjusts the length L of the protruding portion of the wire 2 based on the output of the photoelectric sensor 40D. The brazing apparatus 1D according to the fourth embodiment will be described below with reference to Figures 16, 17A-17C, 18, and 19A-19C. Note that the description of the fourth embodiment will focus on configurations that differ from those of the first to third embodiments.

Figure 16 is a hardware configuration diagram of the brazing apparatus 1D. Figure 17A is a front view of the photoelectric sensor 40D provided in the brazing apparatus 1D. Figure 17B is a bottom view of the photoelectric sensor 40D. Figure 17C is a left side view of the photoelectric sensor 40D. Figure 18 is a flowchart of the length adjustment process of the wire 2 performed by the control unit 60D provided in the brazing apparatus 1D according to embodiment 4. Figure 19A is a bottom view of the nozzle 20 in a state in which the wire 2 is returned in the length adjustment process of the wire 2. Figure 19B is a bottom view of the nozzle 20 when the tip T1 of the wire 2 hits the laser light 42 projected by the photoelectric sensor 40D as a result of the wire 2 being sent out in the length adjustment process of the wire 2. Figure 19C is a bottom view of the nozzle 20 when the wire 2 is adjusted to the target length L1 in the length adjustment process of the wire 2.

As shown in FIG. 16, the brazing apparatus 1D includes a photoelectric sensor 40D in addition to the configuration described in embodiment 1.

As shown in Figures 17A-17C, photoelectric sensor 40D has a casing 48 that is U-shaped in side view and has an opening 47 of the U-shape extending in the left-right direction. Photoelectric sensor 40D projects band-shaped laser light 42 in the front-back and up-down directions from a light-projecting unit (not shown) into the inside of the opening 47. Photoelectric sensor 40D has a light-receiving unit (not shown), and when the amount of light detected by the light-receiving unit decreases, it determines that the band-shaped laser light 42 has been blocked by an object, and outputs a detection signal that indicates that an object has been detected.

Meanwhile, the tip T2 of the nozzle 20 is directed toward the opening 47 of the photoelectric sensor 40D. Then, when the wire 2 is fed by the wire supply mechanism 10, the tip T1 of the wire 2 enters the opening 47 of the photoelectric sensor 40D, as shown in Figures 19A and 19B. Alternatively, the wire 2 is passed through the opening 47, as shown in Figure 19C. As a result, when the tip T1 of the wire 2 reaches a position where it hits the laser light 42, as shown in Figure 19B, the photoelectric sensor 40D outputs the above-mentioned detection signal.

In the brazing apparatus 1D, the photoelectric sensor 40D is used to adjust the length of the wire 2. As shown in FIG. 18, the length adjustment process of the wire 2 is the same as that of the wire 2 described in the third embodiment, except that (1) in steps S52 and S54, the photoelectric sensor 40D is used instead of the displacement sensor 40A described in the third embodiment, (2) there is no step in which the control unit 60D acquires profile data after step S55, and there is no step in which the control unit 60D calculates the number of rotations of the rollers 51 and 52 of the wire feed amount detection sensor 50, and (3) in step S58, the control unit 60D determines whether the number of rotations measured by the encoder 53 exceeds the target number of rotations, rather than whether it exceeds the number of rotations calculated by the control unit 60D. For this reason, a detailed description of the length adjustment process of the wire 2 is omitted.

The target number of rotations used in step S58 of the wire 2 length adjustment process shown in Fig. 18 is a value obtained by dividing the difference between the target length L1 shown in Fig. 19C and the distance L2 from the tip T2 of the nozzle 20 to the laser light 42 by the value of the outer periphery of the rollers 51, 52, assuming that the wire 2 extends linearly to the target length L1 shown in Fig. 19C. The target number of rotations is calculated in advance and stored in the memory device 63, and the control unit 60D reads it out from the memory device 63 in step S58.

As described above, in the brazing apparatus 1D according to embodiment 4, the control unit 60D performs a length adjustment process for the wire 2 before performing the brazing position correction process, as in embodiment 3. Therefore, the brazing apparatus 1D can move the tip T1 of the wire 2 to a more accurate position, as in embodiment 3, and can perform brazing at a more accurate position.

The above describes the brazing apparatus 1A, 1B, 1D and the control method and program for the brazing apparatus 1A, 1B, 1D relating to embodiments 1-4 of the present disclosure, but the brazing apparatus 1A, 1B, 1D and the control method and program for the brazing apparatus 1A, 1B, 1D are not limited to this.

For example, in embodiment 1-4, the wire 2 is inserted into the nozzle 20, and the nozzle 20 holds the wire 2. However, the nozzle 20 is not limited to this. The nozzle 20 may be anything that holds the wire 2. For example, it may be a rod-shaped member with a U-shaped cross section. It is preferable that the nozzle 20 loosely holds the wire 2 so that it can slide.

In embodiment 1-4, the movement mechanism control unit 620 corrects the amount of movement when the movement mechanism 30 moves the nozzle 20 based on the amount of positional deviation of the tip T1 of the wire 2. However, the movement mechanism control unit 620 is not limited to this. The movement mechanism control unit 620 only needs to determine the amount of movement by which the movement mechanism 30 moves the holding mechanism based on the position of the tip T1 of the wire 2 relative to the nozzle 20 determined by the wire tip position calculation unit 610, i.e., based on the position of the tip T1 of the wire 2 relative to the holding mechanism. Therefore, the movement mechanism control unit 620 may operate the movement mechanism 30 to the coordinates where the actual tip T1 of the wire 2 is located, which is the position of the tip T1 of the wire 2 calculated by the wire tip position calculation unit 610.

In embodiment 1-4, the brazing apparatus 1A, 1B, and 1D are provided with an input device 80, but in the brazing apparatus 1A and 1B, the input device 80 is of an optional configuration. For this reason, the brazing apparatus 1A and 1B do not have to be provided with the input device 80. The brazing apparatus 1A, 1B, and 1D may be provided with a display device consisting of a liquid crystal display, and data on the position of the tip T1 of the wire 2 calculated by the wire tip position calculation unit 610, data on the amount of positional deviation, etc. may be displayed on the display device.

In addition, in embodiments 1-4, the moving mechanism 30 is configured as a vertical articulated robot. However, the moving mechanism 30 is not limited to this. The moving mechanism 30 may be any mechanism that moves the nozzle 20 through which the wire 2 is inserted and the displacement sensor 40A or length measurement sensors 40B, 40C. Therefore, for example, the moving mechanism 30 may be a three-axis robot that can move an object in mutually orthogonal X, Y and Z axis directions.

In the first embodiment, pipes 102, 103, 105, and 106 are shown as examples of objects to be brazed, but the brazing apparatuses 1A and 1B are applicable to brazing in general. Therefore, the objects to be brazed are not limited to pipes 102, 103, 105, and 106. For example, the objects to be brazed may be tubes and headers of a heat exchanger.

In the first to fourth embodiments, the brazing position correction program 64 and the brazing program 66 are stored in the storage device 63, but the brazing position correction program 64 and the brazing program 66 may be stored and distributed on a computer-readable recording medium such as a flexible disk, a CD-ROM (Compact Disc Read-Only Memory), a DVD (Digital Versatile Disc), or an MO (Magneto-Optical Disc). In this case, the brazing position correction program 64 and the brazing program 66 stored on the recording medium may be installed in a computer to configure the control units 60A, 60B, and 60D that execute the brazing position correction process and the brazing process.

In addition, the brazing position correction program 64 and the brazing program 66 may be stored in a disk device of a server device on an Internet communication network, and the brazing position correction program 64 and the brazing program 66 may be downloaded, for example, superimposed on a carrier wave.

In addition, when the brazing position correction process and the brazing process are shared and performed by each OS (Operating System), or when they are performed through collaboration between the OS and an application, only the parts other than the OS may be stored on a medium and distributed, or may be downloaded.

Various embodiments and modifications of the present disclosure are possible without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to explain the present disclosure and do not limit the scope of the present disclosure. In other words, the scope of the present disclosure is indicated by the claims, not the embodiments. Various modifications made within the scope of the claims and within the scope of the disclosure equivalent thereto are deemed to be within the scope of the present disclosure.

This application is based on Japanese Patent Application No. 2021-9369, filed on January 25, 2021. The entire specification, claims, and drawings of Japanese Patent Application No. 2021-9369 are incorporated herein by reference.

1A, 1B, 1D brazing device, 2 wire, 3 reel, 4 ideal wire, 5 projected wire image, 10 wire supply mechanism, 11, 12 roller, 13 motor, 20 nozzle, 21 holder, 30 moving mechanism, 40A displacement sensor, 40B, 40C length measurement sensor, 40D photoelectric sensor, 41 light projecting section, 42 laser light, 43, 45 light emitting section, 44, 46 light receiving section, 47 opening, 48 casing, 50 wire feed amount detection sensor, 51, 52 roller, 53 encoder, 60A, 60B, 60D control section, 61 CPU, 62 memory, 63 storage device, 64 brazing position correction program, 65 I/O port, 66 brazing program, 70 heating mechanism, 80 input device, 101 tube expansion section, 102, 103 pipe, 104 Brazing points, 105, 106 pipe, 400 profile data, 401, 402 edge, 403 representative point, 410 profile data, 411, 412 edge, 413 representative point, 610 wire tip position calculation unit, 620 movement mechanism control unit, A distance, A1 axis, D1, D2, D3 direction, L length, L1 length, L2, L3 distance, _P1 , _P2 , _P3 points, Pn, _Pt0 , _Pt1 tip coordinates, Pw wire coordinate, T1, T2 tips.

Claims (7)

a holding mechanism that holds a portion of the wire formed by the brazing material behind the tip;
a wire supply mechanism that feeds the wire to the holding mechanism and causes the wire to protrude from the holding mechanism;
a position sensor for measuring the position of each part of the wire profile in a cross section of the wire that crosses an intermediate portion between the tip and rear portions;
a moving mechanism for moving the holding mechanism;
a wire tip position calculation unit that calculates a position of the tip of the wire with respect to the holding mechanism when the wire protrudes from the holding mechanism by a target length based on the positions of each outer shape part of the wire at the intermediate portion measured by the position sensor; and
a movement mechanism control unit that determines an amount of movement of the holding mechanism by the movement mechanism based on the position of the tip of the wire with respect to the holding mechanism obtained by the wire-tip-position calculation unit;
a wire detection sensor that detects whether or not the tip of the wire is at a specific position on the side of the holding mechanism from which the wire protrudes;
a feed-out amount calculation unit that calculates a feed-out amount of the wire based on a relative position of the specific position with respect to the holding mechanism and a value of the target length of the wire, when the wire supply mechanism moves the tip of the wire to the specific position using an output of the wire detection sensor;
Equipped with
The wire supply mechanism is a brazing apparatus that feeds out the wire based on the feed amount of the wire calculated by the feed amount calculation unit . the wire-tip-position calculation unit calculates a positional deviation between the obtained position of the tip of the wire and a position of the tip of the wire when it is assumed that the wire extends linearly forward from the holding mechanism;
The movement mechanism control unit corrects a movement amount of the holding mechanism by the movement mechanism based on the positional deviation amount calculated by the wire-tip-position calculation unit.
The brazing apparatus of claim 1 . the wire-tip-position calculation unit determines a tilt direction of the wire with respect to the holding mechanism based on the positions of each outer portion of the wire measured by the position sensor and the position of the position sensor with respect to the holding mechanism, and determines a position of the tip of the wire with respect to the holding mechanism from the determined tilt direction and the target length of the wire.
3. The brazing apparatus according to claim 1 or 2. The position sensor is a displacement sensor that measures the displacement of the wire to each part of the outer shape in a cross section of the wire that crosses the intermediate portion.
A brazing apparatus according to any one of claims 1 to 3. the wire supply mechanism includes a roller that rotates in association with the feeding of the wire, and an encoder that detects a rotation number of the roller, and stops feeding of the wire when the rotation number detected by the encoder corresponds to the feed amount of the wire calculated by the feed amount calculation unit.
A brazing apparatus according to any one of claims 1 to 4 . a holding mechanism that holds a portion of the wire formed by the brazing material behind the tip;
a wire supply mechanism that feeds the wire to the holding mechanism and causes the wire to protrude from the holding mechanism;
a position sensor for measuring the position of each part of the wire profile in a cross section of the wire that crosses an intermediate portion between the tip and rear portions;
a moving mechanism for moving the holding mechanism;
a wire detection sensor that detects whether or not the tip of the wire is at a specific position on the side of the holding mechanism from which the wire protrudes;
A method for controlling a brazing apparatus comprising:
a feed amount calculation step of calculating a feed amount of the wire when the wire supply mechanism moves the tip of the wire to the specific position using an output from the wire detection sensor, based on a relative position of the specific position with respect to the holding mechanism and a value of the target length when the wire is protruded from the holding mechanism by the target length;
a wire protruding step of causing the wire supply mechanism to feed out the wire based on the feed amount of the wire calculated in the feed amount calculation step after the wire supply mechanism has moved the tip of the wire to the specific position, and protruding the wire from the holding mechanism by the target length;
a wire tip position calculation step of determining a position of the tip of the wire, which has been protruded by the target length in the wire protruding step , with respect to the holding mechanism, based on the positions of each outer portion of the wire at the intermediate portion measured by the position sensor;
a moving mechanism control step of determining an amount of movement of the holding mechanism by the moving mechanism based on the position of the tip of the wire relative to the holding mechanism obtained in the wire-tip-position calculation step;
A method for controlling a brazing apparatus comprising: a holding mechanism that holds a portion of the wire formed by the brazing material behind the tip;
a wire supply mechanism that feeds the wire to the holding mechanism and causes the wire to protrude from the holding mechanism;
a position sensor for measuring the position of each part of the wire profile in a cross section of the wire that crosses an intermediate portion between the tip and rear portions;
a moving mechanism for moving the holding mechanism;
a wire detection sensor that detects whether or not the tip of the wire is at a specific position on the side of the holding mechanism from which the wire protrudes;
A computer that controls a brazing apparatus comprising:
a feed amount calculation step of calculating a feed amount of the wire when the wire supply mechanism moves the tip of the wire to the specific position using an output from the wire detection sensor, based on a relative position of the specific position with respect to the holding mechanism and a value of the target length when the wire is protruded from the holding mechanism by the target length;
a wire protruding step of causing the wire supply mechanism to feed out the wire based on the feed amount of the wire calculated in the feed amount calculation step after the wire supply mechanism has moved the tip of the wire to the specific position, and protruding the wire from the holding mechanism by the target length;
a wire tip position calculation step of determining a position of the tip of the wire, which has been protruded by the target length in the wire protruding step , with respect to the holding mechanism, based on the positions of each outer portion of the wire at the intermediate portion measured by the position sensor;
a moving mechanism control step of determining an amount of movement of the holding mechanism by the moving mechanism based on the position of the tip of the wire relative to the holding mechanism obtained in the wire-tip-position calculation step;
A program for executing.

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