JP3604037B2 - Resistance welding apparatus and method for hermetic sealing - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a hermetic sealing resistance welding apparatus for sequentially setting an object to be welded such as a cap and a stem of an electronic component on a pair of welding electrodes and welding.
[0002]
[Prior art]
A resistance welder that hermetically seals electronic components such as semiconductor devices or quartz oscillators is a system that welds by supplying the cap of the electronic component to the upper welding electrode and supplying the stem or base side to the lower welding electrode. Things are commonly used.
[0003]
In such a resistance welding machine, there is a mechanism disclosed in Japanese Utility Model Laid-Open Publication No. 51-85028 as a mechanism in which a cap of an electronic component can be easily attached to and detached from an upper welding electrode. The resistance welding machine disclosed in Japanese Utility Model Laid-Open Publication No. 51-85028 has a magnet 3 fixed in a recess of an upper welding electrode 1 holding a cap 4 by suction while a lower welding electrode 2 has a stem as shown in FIG. In a state in which the upper electrode 5 is placed, the upper welding electrode 1 is lowered until a predetermined pressure is applied between the cap 4 and the stem 5, and current is applied to the upper welding electrode 1 and the lower welding electrode 2 to perform welding. When performing welding, a small sealed space is formed by the first chamber member 6 and the second chamber member 7, and then the gas is evacuated from the exhaust passage 8 to weld the cap 4 and the stem 5 in a state close to a vacuum state. Had gone.
[0004]
However, in this apparatus, when the upper welding electrode 1 is raised after welding, there is a problem that the welded material composed of the cap 4 and the stem 5 rises together due to the attraction force of the magnet 3 and the like. The cause of this is that the attraction force of the magnet 3 must be larger than the weight of the cap 4 to overcome the weight of the cap 4 and hold the cap 4, and must be within the range that the weight of the cap 4 and the stem 5 cannot attract and hold. Therefore, in the welding process, dirt adheres to the attracting surface of the magnet 3 or the cap 4 to slightly increase the adhesive force, or the cap 4 is slightly fused to the upper welding electrode 1. When such a phenomenon occurs, the welded material rises together with the magnet 3 as the upper welding electrode 1 rises.
[0005]
As a resistance welding apparatus capable of eliminating such a defect, there is one disclosed in Japanese Patent Publication No. 3-78189. The same symbols as those shown in FIG. 3 indicate corresponding members. This resistance welding apparatus is provided with a vertically movable rod 8 in the cavity of the upper welding electrode 1 as shown in FIG. 4, and when the upper welding electrode 1 is lifted after welding, the rod 8 is moved downward of the cap 4. An operation of pressing the upper surface is performed to remove the welded object including the cap 4 and the stem 5 from the magnet 3 fixed to the electrode tip 1A of the upper welding electrode 1. Reference numeral 9 denotes a gas passage, which is used to exhaust air in a small space closed by the first chamber member 6 and the lower welding electrode 2 in this apparatus.
[0006]
[Problems to be solved by the invention]
However, in any case, such a magnet-fixed welding machine requires a mechanism to lift the cap sent in the horizontal direction and mount it vertically, in order to mount the cap on the upper welding electrode. Has the disadvantage that it must be complicated.
In addition, if the welding speed is to be increased, the lowering speed of the rod must be increased, and the impact given by the rod to the cap is increased, so that the cap is damaged.
Furthermore, since the rod moved up and down, airtightness could not be increased so much, and a high degree of vacuum could not be obtained in a short time.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a cap or a stem or a device capable of supplying, welding and discharging the welded material flexibly.
[0008]
[Means to solve the problem]
According to the present invention, a first welding electrode and a second welding electrode are relatively brought close to each other, and a first workpiece to be held held by the first welding electrode and a first workpiece held by the second welding electrode are held. In the hermetic sealing resistance welding apparatus for performing resistance welding with the second workpiece to be welded, the inside of the first welding electrode is formed in the longitudinal direction of the welding electrode together with the first welding electrode or The support rod is provided so as to be separately movable, a magnet fixed to one end of the support rod, and the support rod is advanced to a position where the magnet can adsorb the first workpiece. And a rod drive for retracting the support rod to its original position after the first workpiece is separated from the magnet after the first workpiece and the second workpiece are welded. Mechanism and the first welding electrode In the stopped state, the support rod is lowered below the lower surface of the first welding electrode, the first workpiece is sucked and held by the magnet, the support rod is raised, and the first support electrode is lifted. Is set on the first welding electrode, and thereafter, the support rod and the first welding electrode are lowered together, and the first welding electrode and the second welding electrode are lowered. And a control means for welding between the first workpiece and the second workpiece, and a control means for welding the first workpiece and the second workpiece.
[0025]
【Example】
Embodiments of the present invention will be described with reference to FIGS. The same symbols as those shown in FIGS. 3 and 4 indicate corresponding members.
An air passage 10 is formed in the upper welding electrode 1, which is the first welding electrode, and one end of the air passage 10 is connected to a normal air supply and exhaust mechanism (not shown). These air supply mechanism and exhaust mechanism are controlled in a predetermined sequence by a control device (not shown). The other end of the air passage 10 extends to a cavity 1B formed below the upper welding electrode 1. The hollow portion 1B is provided with a sliding member 11 serving as a piston rod of an air cylinder and a support rod 12 extending perpendicularly from the sliding member 11, and between the lower surface of the sliding member 11 and the upper surface of the electrode tip 1A. A spring 13 provided around the support rod 12 and an O-ring 14 provided in an annular groove of the sliding member 11 are provided.
[0026]
The support rod 12 moves downward by increasing the air pressure in the air passage 10 to be greater than the elastic force of the spring 13, and retreats upward by the elastic force of the spring 13 by decreasing the air pressure. The support rod 12 moves up and down together with the up and down movement of the upper welding electrode 1. The support rod 12 slides on the center hole wall of the electrode tip 1A in order to minimize the play. Since the airtightness is in a somewhat good state, the hollow part in which the spring 13 exists is provided. It has a vertical groove 12A for exhausting the air of 1B. The magnet 3 is embedded in the lower end of the support rod 12.
[0027]
The magnet 3 is electrically insulated from the support rod 12 to prevent a part of the welding current from flowing when the support rod 12 is made of a metal material, or is directly connected to the cap 4 which is the first workpiece. It is preferable that the support rod 12 is embedded so as to be slightly inside from the lower end face thereof so as not to contact with the support rod 12. However, this is not a necessary condition. It is necessary that the magnet 3 has an attraction force larger than the attraction force capable of attracting and holding the cap 4, and from the viewpoint of reliable attraction and holding, the cap 4 and the stem 5, which is the first workpiece, are simultaneously and surely secured. It is preferable to have a suction force capable of holding by suction.
[0028]
The electrode tip 1A is detachably attached to the upper welding electrode 1, and has a cavity 1A1 for receiving the head of the cap 4 and a thin air passage 1A2 for exhausting the air in the cavity 1A1. The electrode tip 2A of the lower welding electrode 2 includes a flat surface on which the stem 5 is placed, a recess 2A1 for receiving a lead 5A extending from the stem 5, and a thin air passage 2A2 for exhausting air from the recess 2A1. These welding electrodes are generally made of a highly conductive electrode material such as copper.
[0029]
The chamber member 6 is supported so as to slide on the cylindrical outer surface wall of the upper welding electrode 1, and is pressed against the upper surface of the lower welding electrode 2 by a pressing force from a pressing device (not shown). The chamber member 6 is provided with an O-ring 15 in an annular groove formed on the inner wall of the chamber member 6 in order to ensure airtightness with the cylindrical outer surface wall of the upper welding electrode 1. In order to ensure electrical insulation between the chamber member 6 and the lower welding electrode 2, the lower portion of the chamber member 6 is made of an annular electrical insulating material 6A. In order to ensure airtightness with the upper surface of the lower welding electrode 2, an O-ring 16 is provided in an annular groove formed on the lower end surface of the electrically insulating material 6A. The chamber member 6 further includes a ventilation hole 6B. The ventilation hole 6B is connected to a vacuum device such as a vacuum pump through a valve or the like, though not shown, and a gas supply device for supplying an insulating gas in some cases.
[0030]
Next, the operation of the welding device will be described. First, the upper welding electrode 1 and the chamber member 6 are respectively at the original positions, and the support rod 12 is capped when the lowermost end surface of the magnet 3 corresponds to the original position (level X) or the intermediate position (level Y). 4 is received from a transport mechanism (not shown). Thereafter, the upper welding electrode 1 and the chamber member 6 are driven and lowered by the respective drive mechanisms (not shown), and the chamber member 6 is pressed by the lower welding electrode 2 to form a closed space. At this time, the upper welding electrode 1 stops at a position where the cap 4 does not contact the stem 5.
[0031]
Next, the air in the closed space is exhausted from the ventilation hole 6B. At this time, since the cap 4 is not in contact with the stem 5, the air in the cap 4 is quickly exhausted, and the air in the recess 2A1 is also exhausted through the air passage 2A2. 5 does not shift or reverse. Further, since the air in the space 1A1 is exhausted through the air passage 1A2 and the air in the space 1B where the spring 13 is present is exhausted through the vertical groove 12A of the support rod 12, the cap 4 is pressed by the pressure difference. It does not deviate from 1A. Even if these problems do not occur, the air from those cavities gradually leaks into the closed space unless the respective air passages are provided, so that it takes a long time to evacuate the closed space.
[0032]
After evacuation for a predetermined time or when the sealed space reaches a predetermined degree of vacuum, the upper welding electrode 1 is lowered again and stopped with a predetermined pressing force applied between the cap 4 and the stem 5. A welding current is passed between the lower welding electrodes 2 to weld the cap 4 and the stem 5. At this time, if a part of the welding current flows to the cap 4 through the magnet 3 when the magnet 3 is in contact with the cap 4, the support rod 12 is raised to a position where the magnet 3 does not contact the cap 4. If a portion of the welding current does not flow through the magnet 3 to the cap 4 because the magnet 3 is electrically insulated from the support rod 12, the magnet 3 may be in contact with the cap 4.
[0033]
When welding of the cap 4 and the stem 5 is completed, the upper welding electrode 1 and the chamber member 6 start a rising motion. At the time of welding, if the magnet 3 is in contact with the cap 4, compressed air is instantaneously supplied to the air passage 10 almost simultaneously with the start of the rising of the upper welding electrode 1, and a force to push the support rod 12 downward is exerted. As a result, even if the cap 4 is fused to the electrode tip 1A of the upper welding electrode 1, the cap 4 is separated from the electrode tip 1A, so that the welded material between the cap 4 and the stem 5 rises together with the upper welding electrode 1 rising. I can't. However, since there are few cases where the cap 4 is fused to the electrode tip 1A, it is detected that the welding object does not exist on the lower welding electrode 2 immediately after welding, and the support rod 12 is pushed down to remove the welding object from the electrode tip. You may remove from 1A. Then, the upper welding electrode 1, the chamber member 6 and the support rod 12 are raised to their original positions, and prepare for the next welding.
[0034]
Next, a specific first airtight sealing resistance welding method will be described.
With the upper welding electrode 1, the chamber member 6 and the support rod 12 waiting at their original positions, pressurized air is first supplied to the air passage 10 until the lowermost surface of the magnet 3 is at the level Y. 12 is lowered. At that position, the cap 4 gripped by the supply hand 20 of the horizontal transport mechanism shown in FIG. 2A that reciprocates or pivots in a horizontal (perpendicular to the paper) direction from the front or the other side of the paper. The magnet 3 holds the upper surface of the cap 4 by suction at the level Y position as shown in FIG. Thereafter, the horizontal transport mechanism retracts to a position where it does not interfere with welding, and grips the next cap. With the magnet 3 holding the cap 4 by suction, the support rod 12 is lifted, and the head 4A of the cap 4 is in the space 1A1 of the electrode tip 1A of the upper welding electrode 1, and the flange 4B is in the position of the electrode tip 1A. After temporarily stopping at the position set at the tip, the support rod 12 is lowered together with the upper welding electrode 1. The chamber member 6 starts lowering when the supply hand 20 of the horizontal transport mechanism (not shown) is retracted. When the chamber member 6 presses the lower welding electrode 2 to form a closed space, a vacuum device (not shown) operates to rapidly start suction from the vent hole 6B of the chamber member 6. The support rod 12 and the upper welding electrode 1 are temporarily stopped at such a height that the cap 4 does not come into contact with the stem 5, and when the desired degree of vacuum is obtained, the support rod 12 and the upper welding electrode 1 are lowered again to fall between the cap 4 and the stem 5. The welding is stopped in a state where an appropriate pressing force is applied, and welding is performed by supplying a welding current between the upper welding electrode 1 and the lower welding electrode 2 from a power supply device (not shown). Thereafter, finally, the upper welding electrode 1, the chamber member 6 and the support rod 12 return to their original positions.
In this method, since the support rod 12 also serves as a vertical transport mechanism for the cap 4, only the horizontal transport mechanism is required, and the structure of the apparatus can be simplified.
[0035]
Next, the second hermetic sealing resistance welding method is different from the first hermetic sealing resistance welding method in that the magnet 3 attracts and holds the cap 4 in the first hermetic sealing resistance welding method. In this state, the support rod 12 rises, and the head of the cap 4 is set in the space 1A1 of the electrode chip 1A. In contrast, in this method, the level of the support rod 12 is raised while the magnet 3 holds the cap 4 by suction. Stopping at Y, the upper welding electrode 1 descends to set the head of the cap 4 in the space 1A1 of the electrode tip 1A.
In this method, the upper welding electrode 1 and the support rod 12 are only moved down by the welding process of the cap 4 and the stem 5, so that high-speed welding can be performed.
[0036]
Next, a third hermetic sealing resistance welding method is the same as the first and second hermetic sealing resistance welding methods, as shown in FIG. Is characterized by being away from the cap 4. Even if the support rod 12 is made of a metal material and the magnet 3 and the support rod 12 are not electrically insulated, a part of the welding current does not flow to the cap 4 through the magnet 3. Therefore, unnecessary welding marks are not formed on the cap 4.
[0037]
Next, in the fourth resistance welding method for hermetic sealing, the upper welding electrode 1 starts to rise after the cap 4 and the stem 5 are welded as described above. Is prevented from rising together with the upward movement of the upper welding electrode 1. Therefore, even if the cap 4 is fused to the welding tip 1 </ b> A, the welded material is securely held by the magnet 3. The prohibition time is set very short, after which the support rod 12 rises to the level Y and stops. The discharge hand 21 of the horizontal transport mechanism shown in FIG. 2D that reciprocates or pivots in a horizontal (perpendicular to the paper) direction from the near side or the other side of the plane of the drawing, the welding object held by the magnet 3 by suction. Grasp and retreat. Thereafter, the support rod 12 returns to the original position.
According to this method, high-speed welding is possible, and even if the cap 4 is fused to the welding tip 1A, the welded material can be reliably discharged.
[0038]
Next, in the fifth hermetic sealing resistance welding method, the upper welding electrode 1 starts to rise after the cap 4 and the stem 5 are welded as described above. Ascending with the upward movement of the upper welding electrode 1 is prohibited, and after the welding object is attracted to and held by the magnet 3, it immediately rises at a higher speed than the upper welding electrode 1 by the elastic force of the spring 13. Therefore, the work is prevented from rising together with the support rod 12 by the electrode tip 1A of the upper welding electrode 1 slightly above the electrode tip 2A of the lower welding electrode 2, and returned to the electrode tip 2A. Thereafter, the weld is discharged by a normal discharge mechanism.
According to this method as well, high-speed welding is possible, and even if the cap 4 is fused to the welding tip 1A, the welded material can be reliably discharged.
[0039]
Next, in the sixth resistance-welding method for hermetic sealing, after the cap 4 and the stem 5 are welded as described above, the upper welding electrode 1 and the support rod 12 start rising while holding the welded object. . Then, the upper welding electrode 1 continues to move upward to its original position, while the support rod 12 rises to the level Y and stops. Therefore, even if the cap 4 is fused to the welding tip 1 </ b> A, the welded material is securely held by the magnet 3. Thereafter, the discharge hand 21 of the horizontal transport mechanism shown in FIG. 2D moves forward, and grips and holds the welding object held by the magnet 3. Thereafter, the support rod 12 returns to the original position.
According to this method as well, high-speed welding is possible, and even if the cap 4 is fused to the welding tip 1A, the welded material can be reliably discharged.
The drive mechanism of the support rod 12 may use a hydraulic cylinder. In this case, a piston rod of the hydraulic cylinder can be used as the support rod 12, and the support rod 12 can be fixed to the piston rod. Further, a combination of a rotating device such as a stepping motor and a conversion mechanism such as a pinion and a rack for converting a rotary motion into a linear motion may be used.
[0040]
【The invention's effect】
As described above, according to the present invention, a magnet is provided at the tip of the support rod which can move up and down independently of the upper welding electrode, and this magnet is configured to attract and hold the cap or the welded object. The object of the present invention is to provide a resistance-welding apparatus for hermetic sealing, which is flexible and capable of adopting a welding method suitable for each purpose. Further, according to the welding method of the present invention, it is possible to simplify the mechanism of the resistance welding device for hermetic sealing, or to reliably discharge the welded article regardless of the state, or to make unnecessary welding marks on the welded article. Effects such as avoidance can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an embodiment of the present invention.
FIG. 2 is a diagram for explaining an embodiment of the present invention.
FIG. 3 is a diagram for explaining a conventional technique.
FIG. 4 is a diagram for explaining a conventional technique.
[Explanation of symbols]
1. First welding electrode (upper welding electrode)
1A: electrode tip of first welding electrode 2: second welding electrode (lower welding electrode)
2A: electrode tip of second welding electrode 3: magnet 4, first workpiece (cap)
5 Second workpiece (stem)
6 chamber member 10 air passage 12 formed in first welding electrode 12 support rod 13 spring 20 supply hand 21 of horizontal transfer mechanism ..Ejection hand of horizontal transport mechanism

Claims (7)

The first welding electrode and the second welding electrode are relatively close to each other, and a first workpiece to be held held by the first welding electrode and a second workpiece held by the second welding electrode. In a resistance welding device for hermetic sealing for resistance welding with a workpiece to be welded,
A support rod arranged to move inside the first welding electrode in the longitudinal direction of the welding electrode together with or separately from the first welding electrode;
A magnet fixed to one end of the support rod;
The support rod is advanced to a position where the magnet can adsorb the first workpiece, and after the first workpiece and the second workpiece are welded, the first magnet is welded to the second workpiece. A rod drive mechanism for retracting the support rod to its original position after the workpiece has left;
In a state where the first welding electrode is stopped at a predetermined position, the support rod is lowered below the lower surface of the first welding electrode, and the first workpiece is sucked and held by the magnet, The support rod is raised, and the first workpiece is set on the first welding electrode. Thereafter, the support rod and the first welding electrode are lowered together to form the first welding electrode. Control means for energizing between the first welding electrode and the second welding electrode to weld the first workpiece and the second workpiece;
A resistance welding apparatus for hermetic sealing characterized by having: The first welding electrode and the second welding electrode are relatively close to each other, and a first workpiece to be held held by the first welding electrode and a second workpiece held by the second welding electrode. In a resistance welding device for hermetic sealing for resistance welding with a workpiece to be welded,
A support rod arranged to move inside the first welding electrode in the longitudinal direction of the welding electrode together with or separately from the first welding electrode;
A magnet fixed to one end of the support rod;
The support rod is advanced to a position where the magnet can adsorb the first workpiece, and after the first workpiece and the second workpiece are welded, the first magnet is welded to the second workpiece. A rod drive mechanism for retracting the support rod to its original position after the workpiece has left;
In a state where the first welding electrode is stopped at a predetermined position, the support rod is lowered below the lower surface of the first welding electrode, and the first workpiece is sucked and held by the magnet, In a state where the support rod is stopped at the position where the support rod is held by suction, the first welding electrode is lowered, and the first workpiece is set on the first welding electrode. Is lowered together with the welding electrode and the support rod, and a current is supplied between the first welding electrode and the second welding electrode to weld the first and second workpieces. Control means for performing;
A resistance welding apparatus for hermetic sealing characterized by having: In claim 1 or claim 2,
A resistance welding apparatus for hermetic sealing, wherein the magnet is separated from the first workpiece when welding the first workpiece and the second workpiece. The first welding electrode and the second welding electrode are relatively close to each other, and a first workpiece to be held held by the first welding electrode and a second workpiece held by the second welding electrode. In a resistance welding device for hermetic sealing for resistance welding with a workpiece to be welded,
After the first workpiece and the second workpiece are welded, the first welding electrode starts to rise, and when the first welding electrode starts to rise, the support rod moves to the first welding electrode. Holding the upper surface of the object to be welded, separating the first object to be welded from the first welding electrode, and thereafter, the support rod rises at a higher speed than the first welding electrode, and Control means for cooperating with the first welding electrode to remove the workpiece adsorbed and held by the first welding electrode;
A resistance welding apparatus for hermetic sealing characterized by having: In claim 1,
An exhaust passage for discharging air in a space surrounded by the first welding electrode, the first workpiece, and the support rod is formed in the first welding electrode. Resistance welding equipment for hermetic sealing. In claim 1,
An exhaust passage for discharging air in a space surrounded by the second welding electrode and the second workpiece is formed in the second welding electrode, for hermetic sealing. Resistance welding equipment. The first welding electrode and the second welding electrode are relatively close to each other, and a first workpiece to be held held by the first welding electrode and a second workpiece held by the second welding electrode. In a resistance welding device for hermetic sealing for resistance welding with a workpiece to be welded,
After welding the first workpiece and the second workpiece, the first welding electrode is started to rise, and when the first welding electrode starts to rise, the first welding electrode is lifted. A support rod disposed inside the welding electrode so as to be able to move together with or separately from the first welding electrode in the longitudinal direction of the welding electrode presses an upper surface of the first workpiece, and The first welding object is separated from the first welding electrode, and thereafter, the support rod is raised at a higher speed than the first welding electrode, and is moved to the magnet fixed to one end of the support rod. Control means for removing the workpiece held by suction in cooperation with the first welding electrode;
A resistance welding apparatus for hermetic sealing characterized by having:

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