JPH07290351A - Machining device and machining method therewith - Google Patents

Abstract

PURPOSE:To shorten the machining lead time without increasing the revolving speed and feeding speed of a tool, prevent the enlargement of a device, reduce the machining cost, simplify the control of a manipulator, and reduce the facility cost. CONSTITUTION:The drive and positions of prescribed tools (grinding wheels) 30, 31 provided on a manipulator (robot) 10 and the relative attitudes of the tools against a work (die) 50 can be controlled, and the work 50 can be fed for machining in this machining device. Multiple tools 30, 31 are provided on the manipulator 10 so that their drive, positions, and relative attitudes against the work 50 can be independently controlled. The interference avoidance distance for avoiding the mutual interference during the respective machining work is set between the tools 30, 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing device using a manipulator such as an industrial robot and a processing method using this processing device.

[0002]

2. Description of the Related Art An example of this type of processing apparatus is Japanese Patent Laid-Open No. 2-7.
It is disclosed in Japanese Patent No. 6006. In the technique of this publication, a robot equipped with a tool (grinding wheel) is controlled to move the tool while rotating it along the surface of a mold, which is a workpiece, thereby grinding the surface of the mold. ing. Then, in the grinding of the die, the tool is repeatedly replaced with a grindstone with a coarse grain size and a grindstone with a fine grain size until the desired surface roughness is obtained.

[0003]

However, in this case, the lead time from the start to the completion of the machining work becomes long and the machining cost increases. Therefore, it is conceivable to increase the rotation speed and feed rate of the tool, but in that case it is necessary to improve the equipment function to avoid machining defects, and as a result, the size of the processing equipment will increase. Is not realistic. Also, by using multiple manipulators such as robots to process one workpiece at the same time,
It is possible to shorten the processing lead time, but for that purpose, complicated control is required to prevent manipulators from interfering with each other. As a result, the control system of the manipulator becomes complicated, and even with the complicated control data created, if the work piece is produced in small numbers like a die (for example, one item production), it will be used with one use, These increase costs.

The problem to be solved by the present invention is to enable a plurality of tools provided on one manipulator to simultaneously machine a work piece while avoiding mutual interference between them, so that the number of rotations of the tool and the feed rate can be increased. It is intended to reduce the processing cost while avoiding the enlargement of the apparatus by shortening the processing lead time without increasing the speed, and simplifying the manipulator control to reduce the equipment cost.

[0005]

In order to solve the above problems, the processing apparatus and the processing method using the same according to the present invention are configured as follows. First, the structure according to claim 1 is configured such that a manipulator provided with a predetermined tool can control the drive, position and relative attitude of the tool with respect to a workpiece, and can perform a feed operation for processing. In the processing apparatus, a plurality of tools are independently provided in the manipulator so that the drive, position, and relative attitude to the workpiece can be controlled, and the tools are respectively connected to each other. The interference avoidance distance is set so as to avoid mutual interference during the machining work. In the structure according to claim 2, each of the tools is a grinding wheel having a different grain size. According to a third aspect of the present invention, there is provided a machining method using the machining apparatus according to the first or second aspect, in which a tool that is performing a machining operation in advance feeds the interference avoidance distance by a feed operation of the manipulator. If you get
Following this, the driving of the tool, the position, and the control of the relative posture with respect to the workpiece are started.

The control of the relative attitude of the tool with respect to the work piece means the adjustment of the inclination and height of the tool with respect to the work surface. The manipulator is a general term for a multi-axis robot or a multi-axis machine tool.

[0007]

According to the structure of the first aspect of the present invention, by controlling the manipulator, a plurality of tools provided on the manipulator are independently driven, and the attitude relative to the workpiece is controlled. By moving the manipulator, the workpiece is simultaneously machined by each tool. Therefore, the lead time from the start to the end of machining can be shortened without increasing the rotational speed for driving the tool and the feed speed of the manipulator. Further, during the machining work, the interference avoidance distance is always maintained between the respective tools, so that the work can be performed while avoiding the interference between the tools by a simple control. In the structure according to claim 2, it is possible to simultaneously grind the work piece with a plurality of grinding wheels having different grain sizes, whereby, for example, rough grinding of the work piece is performed while finish grinding is performed in accordance with the rough grinding. It becomes possible to do. In the configuration of claim 3,
If the tool that is doing the machining work in advance between each tool is sent by the above-mentioned interference avoidance distance, the machining by the tool following it will be started, and of course the interference of each tool can be avoided. Thus, wasteful driving of tools before the start of machining work is eliminated.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a perspective view showing a mold processing device. As is clear from this drawing, the die machining apparatus controls a robot 10 used as an example of a manipulator, a machining table 52 on which a die 50 (semi-finished product) as a workpiece is mounted, and a robot 10. The control unit 40 and the personal computer 44 are mainly configured. The control unit 4
0 is provided with an operation unit 42 for designating and inputting processing conditions of the die 50.

The robot 10 is a multi-axis robot having 10 axes (degrees of freedom), and a cross rail 14 is provided so as to be able to move up and down with respect to a column 12 which can reciprocate on a traveling rail 36. The cross rail 14 is provided with an arm 16 capable of advancing in a direction toward the processing table 52 and retracting in an opposite direction.
A rotary shaft 18 extending downward is provided at the tip of the arm 16.
A beam 20 is supported through the beam 20.
6 can be rotated around the axis together with the rotation shaft 18. The beam 20 has a slide arm 2 which is reciprocally movable in the longitudinal direction at its lower surface.
2 and a slide arm 23 that can be moved up and down on the side surface of the beam 20.

At the ends (lower ends) of both slide arms 22 and 23, wrists 24 capable of turning in two directions about axes A and B are individually attached. . Each of these wrist portions 24 is provided with a spindle head 26, and both spindle heads 26 are provided with grinding wheels 30 and 31 which are tools for processing. Both spindle heads 26 have a driving source (air motor) for rotationally driving the respective grinding wheels 30, 31 and a floating mechanism for absorbing an axial impact load applied to the grinding wheels 30, 31 (both shown in the drawings. Outside) is built in.

In the robot 10, the column 12 reciprocates with respect to the traveling rail 36, the cross rail 14 moves up and down with respect to the column 12, the arm 16 moves forward and backward with respect to the cross rail 14, and the beam 20 moves with respect to the arm 16. The operation of rotating together with the rotary shaft 18 is controlled by a signal from the control unit 40 based on the processing data input to the personal computer 44. Also, the beam 2
Reciprocating movement of slide arm 22 relative to 0 and beam 20
The raising / lowering operation of the slide arm 23 with respect to is controlled individually by a signal from the controller 40. Similarly, with respect to the two-way turning motions about the axes A and B of the wrists 24 and the driving of the grinding wheels 30 and 31 of the spindle heads 26, the signals from the controller 40 are individually used. It can be controlled independently.

Next, the mold 5 produced by the processing apparatus described above.
The processing (grinding) work of 0 will be described. In this work, one of the above-mentioned grinding wheels 30 and 31 is for roughing, and the other one is for finishing. FIG. 2 is a plan view showing an example of the grinding operation of the both grinding wheels 30 and 31 with respect to the die 50. As shown in this figure, an interference avoidance distance L is set between the two grinding wheels 30 and 31 prior to the work. The interference avoidance distance L is a distance that does not cause mutual interference in the grinding work of the grinding wheels 30 and 31 under the control of the robot 10, and the setting is performed by moving the slide arm 22 with respect to the beam 20.

The robot 10 is controlled on the basis of a signal from the control section 40, and the roughing grinding wheel 30 starts grinding the surface of the die 50. At this time, the grinding wheel 31 for finishing is held at a position where it does not come into contact with the surface of the mold 50 by the ascending operation of the slide arm 23 with respect to the beam 20, and the rotational drive is also stopped. When the grinding of the mold 50 by the roughing grinding wheel 30 advances by the interference avoidance distance L and the finishing grinding wheel 31 reaches the grinding start point, the slide arm 23 descends to move the grinding wheel. At the same time when 31 is brought into contact with the surface of the mold 50, its rotational drive is started. After that, the roughing of the die 50 and the subsequent finishing are simultaneously performed by the grinding wheels 30 and 31 while keeping the interference avoidance distance L therebetween. Note that it is necessary to perform rough machining a plurality of times in the die 50 with a large amount of grinding. In this case, it is possible to shorten the working time for rough machining by using both grinding wheels 30 and 31 for rough machining.

Since the surface of the die 50, which is the work piece, is a three-dimensional free-form surface, both the grinding wheels 3 during the grinding work.
0 and 31 are independently controlled so that a predetermined posture is maintained with respect to the surface of the mold 50 at each grinding position. One of the controls is the both grinding wheels 30 and 31.
Is a control for keeping the spindle axis line of (1) at a right angle to the surface of the mold 50, and this is realized by individually pivoting the both wrist portions 24 around the axis lines A, B. Further, for this control, the both grinding wheels 3 with respect to the change of the surface height of the die 50
Position adjustment of 0, 31 is also included, but this is for the robot 10
The vertical movement of the cross rail 14 with respect to the column 12 is performed. However, when there is a difference in height between the grinding positions of the two grinding wheels 30 and 31, one of the grinding wheels 3 is moved by moving the slide arm 23 up and down relative to the beam 20.
This is dealt with by adjusting the height of 1. Therefore, both grinding wheels 30 and 31 against changes in the surface height of the die 50
As a result, the position adjustments are also individually controlled.

Further, both grinding wheels 30, 3 for the die 50
The feed operation of No. 1 is the movement of the robot 10 (column 12) with respect to the traveling rail 36.
Both 0 and 31 are sent at the same speed. So each grindstone 30,
If the optimum processing conditions in 31 are different, it is possible to deal with them by individually controlling the respective rotation speeds or the pressing force against the mold 50. The adjustment of the pressing force of both grinding wheels 30 and 31 is the same control as the adjustment of the height position of the grinding wheels 30 and 31 with respect to the mold 50, and is designated and input in advance by the operation unit 42 of the control unit 40. .

Next, the two grinding wheels 30 and 31 are attached to the die 50.
A case where grinding is performed while feeding at a constant feed angle (polishing angle) will be described. The feed angle θ is 4 in Fig. 3.
The plan view shows the grinding operation of both the grindstones 30 and 31 when set at 5 °. Both grinding wheels 30 and 31 at this time
In the feeding operation, the robot 10 (column 12) is moved along the traveling rail 36, and at the same time, the cross rail 14 is moved.
With respect to the above, it is realized by moving the arm 16 forward and backward. In order to avoid uneven grinding (uneven polishing), the beam 20 is rotated around the axis of the rotary shaft 18 in parallel with the feeding operation. As a result, both grinding wheels 30, 3
When 1 reaches the boundary of the processing region, the beam 20 and the boundary line are controlled to be parallel to each other as shown in FIG. As a result, the loci of the two grinding wheels 30 and 31 become arcuate due to the combination of the basic feeding operation and the rotation of the beam 20.

Further, in the grinding (polishing) of the die 50, the work is often performed while changing the feed angle (polishing angle) of the grinding wheels 30 and 31 in order to obtain a uniformly machined surface over the whole. If there is such a request,
In the processing apparatus of this embodiment, the feed angles of both grinding wheels 30 and 31 can be individually changed even in one grinding operation. FIG. 4 shows both grindstones 30 when grinding is performed while reciprocally moving the slide arm 22 with respect to the beam 20.
The operation of 31 is shown in plan view. As is apparent from this figure, one grinding wheel 31 is fed based on the basic feeding operation under the control of the robot 10, and the other grinding wheel 30 is fed.
Is sent in a zigzag trajectory in which the reciprocating movement of the slide arm 22 is superimposed on the basic feeding operation.

In the above embodiment, the work piece is not limited to the die 50, and the grinding wheels 30 and 31 may use tools such as cutting blades depending on the type of work performed on the work piece. is there. Moreover, the number of tools in one robot 10 is not limited to two, but even when three or more tools are used, it is necessary to set the interference avoidance distance L between them.

[0019]

According to the present invention, the machining lead time can be shortened by simultaneous machining with a plurality of tools without increasing the rotational speed and feed rate of the tools, and the machining cost can be reduced while avoiding an increase in the size of the apparatus. While the manipulator is equipped with a plurality of tools, its control is simplified and the equipment cost is reduced. In addition, it is possible to eliminate unnecessary driving of tools during machining work.

[Brief description of drawings]

FIG. 1 is a perspective view showing a mold processing apparatus.

FIG. 2 is a plan view showing an example of a grinding operation of a grinding wheel.

FIG. 3 is a plan view showing a grinding operation of a grinding wheel when a feed angle is set.

FIG. 4 is a plan view showing a grinding operation when the feed angles of two grinding wheels are individually changed.

[Explanation of symbols]

 10 Robot (Manipulator) 30, 31 Grinding Wheel (Tool) 50 Die (Workpiece) L Interference Avoidance Distance

Claims (3)

[Claims] 1. A machining system in which a manipulator provided with a predetermined tool is configured to control the drive and position of the tool and the relative attitude of the tool with respect to a workpiece, and to be capable of a feed operation for machining. In the apparatus, the manipulator is provided with a plurality of tools independently of each other so as to be able to control the drive, position, and relative attitude with respect to the workpiece, and between the tools, during each machining operation. The processing apparatus is characterized in that an interference avoidance distance is set so as to avoid mutual interference with each other. 2. The processing apparatus according to claim 1, wherein each of the tools is a grinding wheel having a different grain size. 3. A machining method using the machining apparatus according to claim 1 or 2, wherein a tool that is performing a machining operation in advance is fed by the feed operation of the manipulator by the interference avoidance distance. A machining method characterized by starting driving of a tool following this, control of a position, and a relative posture with respect to a workpiece.