JP7333601B2 - Electrode supply device for spot welding - Google Patents

Description

TECHNICAL FIELD The present invention relates to a spot welding electrode supply device capable of supplying electrodes, for example, when exchanging the electrodes of a spot welding gun used in a factory or the like.

BACKGROUND ART Conventionally, in an automobile production line, a vehicle body frame is assembled by connecting a plurality of press-formed products by spot welding, and this spot welding is generally performed using a device called a welding gun.

By the way, the electrode is attached to the shank of the welding gun by fitting the tip of the electrode into the fitting recess of the electrode. Since the electrodes are worn out by repeated spot welding, they need to be replaced periodically. Therefore, in order to efficiently attach the electrode to the shank of the welding gun when replacing the electrode, an electrode storage device for spot welding is installed in the automobile production line.

For example, the electrode storage device disclosed in Patent Document 1 includes a rectangular tube-shaped storage case having a storage passage therein, in which the electrodes are arranged linearly in a direction orthogonal to the central axis thereof, and , a plurality of fitting recesses can be accommodated in a state of being arranged side by side so as to open in the same direction. One end of the accommodation passage is formed with an electrode extraction opening for taking out the electrodes from the accommodation passage, while the other end of the accommodation passage is provided with one or a plurality of electrodes accommodated in the accommodation passage. is provided to one end of the housing passage by means of a spring force. A removal restriction member movable in a direction perpendicular to the longitudinal direction of the storage case is disposed on one end side of the storage passage. The take-out restricting member blocks part of the electrode outlet while being moved to one side by the biasing force of the coil spring to restrict the electrode from being taken out from the electrode outlet. The electrode extraction opening is opened in the state of moving to the left, so that the electrode can be extracted from the electrode extraction opening. Then, the tip of the shank of the welding gun attached to the tip of the arm of the industrial robot is fitted into the fitting recess of the electrode, which is in contact with the removal restricting member, among the electrodes arranged side by side in the accommodation passage, and the electrode is attached to the electrode. When moved toward the outlet, the removal restricting member moves to the other side against the urging force of the coil spring to remove the electrode from the opened electrode outlet, and then the electrode adjacent to the removed electrode is pressed. The spring force of the unit moves toward one end of the housing passage, and the urging force of the coil spring makes contact with the removal restricting member that has moved toward one side, thereby restricting removal from the electrode outlet.

Japanese Patent Publication No. 2013-514182

By the way, in the case of a stationary type welding gun fixed at a predetermined position in a production line, if an attempt is made to automatically replace the electrode using an electrode storage device such as that disclosed in Patent Document 1, for example, the electrode storage device cannot be used for industrial purposes. It must be transported to a stationary welding gun by a robot or the like. Then, when the electrode stored in the electrode storage device runs out, the electrode storage device cannot be refilled with new electrodes until the industrial robot that transports the electrode storage device stops in order to perform the work safely. There is a problem that production efficiency deteriorates.

In order to avoid this, the electrode storage device is installed at a predetermined position, and the electrodes stored in the electrode storage device are transported one by one to the stationary welding gun using a dedicated transport means. can be considered.

However, in order to attach the electrode to the tip of the shank of a stationary welding gun when the electrode is transported by a dedicated transport means, it is necessary to move the electrode so that the opening of the electrode is not blocked. However, in the case of the electrode storage device of Patent Document 1, there is no space around the electrodes positioned corresponding to the electrode extraction openings in the storage passage, and the openings of the electrodes cannot be covered by the transport means. There is a problem that it cannot be grasped so that it does not come off.

Further, when housing a so-called male taper type electrode in which a fitting portion for externally fitting a shank tip of a welding gun protrudes on the base end side in an electrode storage device such as that disclosed in Patent Document 1, the electrode outlet in the housing passage has an electrode outlet. When attempting to externally fit the shank tip of the welding gun to the fitting portion of the correspondingly positioned electrode, there is also the problem that the shank tip comes into contact with the electrode adjacent to the electrode to be fitted, making it impossible to attach the electrode. .

That is, in order to supply the electrode to a stationary spot welding gun or a spot welding gun for a male taper type electrode, the electrode is attached to the tip of the shank with a wide space around the fitting portion. There has been a strong demand for an electrode supply device that can supply electrodes one by one.

The present invention has been made in view of such a point, and an object of the present invention is to provide an electrode supply device capable of supplying electrodes one by one while providing a wide space around a fitting portion with a shank. It is to provide a device.

In order to achieve the above object, the present invention provides an electrode storage unit that stores electrodes at a predetermined position, and after sending the electrodes from the electrode storage unit to the electrode standby position, the electrode is positioned at the electrode standby position. It is characterized by gripping the electrode from its side.

Specifically, the following solutions were taken for a spot welding electrode supply device capable of supplying spot welding electrodes.

That is, in the first invention, an electrode storage unit that is installed at a predetermined position and can store a plurality of electrodes, an electrode delivery unit that sequentially takes out electrodes from the electrode storage unit and delivers them to an electrode standby position, and the electrode standby unit. a gripping unit capable of gripping the position electrode in a posture that does not block the opening of the fitting recess into which the tip of the shank of the spot welding gun is fitted , wherein the fitting recess opens in the same direction. a storage case having an electrode storage portion capable of storing a plurality of electrodes in a state in which they are held together, and an electrode extraction port communicating with the electrode storage portion; The electrode is provided with a slide body which, when advanced, is inserted into the fitting recess of the electrode accommodated at a position corresponding to the electrode outlet of the electrode accommodation part, and the electrode into which the tip part of the slide body is inserted. presses the slide body so as to pass through the electrode extraction opening and feeds the slide body to the electrode standby position.

In a second invention according to the first invention , the electrode delivery unit has a piston rod that can extend and contract in a direction orthogonal to the center line of the slide body, and when the piston rod is extended , the It is characterized by comprising a first fluid pressure cylinder that presses the slide body and feeds it to the electrode standby position .

In a third invention, in the second invention, the electrode delivery unit guides the electrode, which passes through the electrode outlet and is further pressed by the first fluid pressure cylinder, from the electrode outlet to the electrode standby position. It is characterized by comprising a guide member having a groove that

In a fourth invention, in the second or third invention, the electrode delivery unit advances the slide body in conjunction with the extension operation of the piston rod, and interlocks with the contraction operation of the piston rod. It is characterized by having a cam mechanism for retracting the slide body.

In a fifth aspect according to the fourth aspect, the cam mechanism is provided on the outer peripheral surface of the slide body and protrudes in a direction perpendicular to both the center line of the slide body and the extension/contraction direction of the piston rod. and a groove-shaped or slit-shaped first guide hole that extends at a slant so as to be positioned gradually in the advancing direction of the slide body as it goes in the contraction direction of the piston rod, and that guideably supports the projection. It is characterized by being

In a sixth invention according to the fifth invention, when the piston rod is extended, the electrode delivery unit applies a load to the slide body that is smaller than the force applied to the slide body by the extension operation of the piston rod. While the load is generated in the contraction direction of the piston rod, when the piston rod is contracted, a load smaller than the force applied to the slide body by the contraction action of the piston rod is applied to the slide body in the extension direction of the piston rod. It is characterized by having a brake mechanism to generate.

In a seventh invention according to any one of the first to sixth inventions, the gripping unit comprises a second fluid pressure cylinder that moves the block body along the cylinder center line, and a second fluid pressure cylinder that extends along the cylinder center line. and a pair of claw members arranged side by side with the center line of the cylinder as a boundary and having gripping portions facing each other at their distal ends; and a support member that rotatably supports the claw member, and in the middle part of the claw member, a groove shape or a slit shape that is inclined so as to approach the other claw member as it goes toward the base end side of the claw member The block body is provided with pins that are movably fitted into the second guide holes of the claw members, and the claw members move the electrode at the electrode standby position. When gripping, the electrodes are positioned between the gripping portions of the claw members, the block body is moved to one side, and the second guide holes guide the pins to the one end side. As a result, the two claw members approach each other, and this approaching action grips the electrode. When the electrode gripped by the two claw members is released, the block body is moved to the other side. It is characterized in that the second guide holes guide the pins to the other end side so that the claw members are separated from each other, and this separation action releases the electrodes.

In an eighth invention, in any one of the first to seventh inventions, the spot welding gun is of a stationary type and includes a transport unit for transporting the gripping unit to a position for supplying the electrode to the spot welding gun. It is characterized by

In a ninth aspect according to the eighth aspect, the transfer unit includes an electrode removal unit capable of removing the electrode fitted to the shank of the spot welding gun from the shank by twisting the electrode with respect to the shank. is further attached.

In the first invention, since the opening of the fitting recess of the electrode gripped by the gripping unit is open at the electrode standby position, for example, by moving the gripping unit to the stationary spot welding gun, the gripping unit The electrode can be attached to the tip of the shank of the welding gun while it is firmly held, or the tip of the shank of the spot welding gun for the male taper electrode can be brought closer to the electrode standby position so that it can be brought into contact with another electrode. The electrode can be attached to the tip of the shank without

In the second invention, the operation of taking out the electrode from the storage case by the electrode delivery unit can be performed by only two simple operations, the forward movement of the slide body and the extension movement of the piston rod by the first fluid pressure cylinder. Therefore, the structure of the electrode delivery unit becomes simple, and the occurrence of failure of the device can be suppressed.

In the third aspect of the invention, the electrode taken out of the storage case can be delivered to the electrode standby position by using the extension operation of the piston rod for taking out the electrode from the storage case in the electrode delivery unit. Therefore, there is no need to separately prepare equipment for sending the electrodes taken out from the storage case to the electrode standby position, and the structure can be made at a reduced cost.

In the fourth aspect of the invention, the extension and retraction of the piston rod causes the slide body to advance and retreat, so there is no need to separately prepare equipment for causing the slide body to advance and retreat along its center line. , and can be constructed at a lower cost.

In the fifth invention, when the piston rod extends while the slide body is in the original position, the protrusion is guided from one end of the first guide hole to the other end of the first guide hole, thereby moving the slide body forward and moving forward. is inserted into the fitting recess of the electrode corresponding to the electrode outlet. When the piston rod is further extended, the projection is maintained at the other end of the first guide hole, and the slide body moves in the direction of extension of the piston rod. It is sent out to the electrode waiting position while passing through and being guided by the guide member. Thereafter, when the piston rod is contracted while the electrode is positioned at the electrode standby position, the projection is guided from the other end of the first guide hole to the one end of the first guide hole, so that the slide body is retracted and its tip end is retracted. Disengage from the fitting recess of the electrode. When the piston rod is further contracted, the projection is held at one end of the first guide hole, and the slide body moves in the contraction direction of the piston rod and returns to its original position. In this way, each electrode housed in the storage case can be sequentially moved to the electrode standby position only by the expansion and contraction of the piston rod in the first fluid pressure cylinder, and the equipment can be simple and low cost. can.

In the sixth invention, when the piston rod extends with the protrusion positioned at one end of the first guide hole, the load applied to the slide body by the brake mechanism causes the slide body to move along with the piston rod. The protrusion is smoothly guided by the first guide hole without moving in the extension direction of the slide body, thereby advancing the slide body. On the other hand, when the piston rod contracts with the projection positioned at the other end of the first guide hole, the load applied to the slide body by the brake mechanism causes the slide body to move in the contraction direction of the piston rod together with the piston rod. The protrusion is smoothly guided to the first guide hole without moving, and the slide body moves backward. In this manner, the extension and retraction of the piston rod can smoothly advance and retract the slide body.

In the seventh invention, when the block body is moved to one side by the second fluid pressure cylinder, the gripping portions of both claw members are separated from each other. , it becomes easier to guide the electrode between the gripping portions of the claw members. Therefore, it is possible to increase the speed of the gripping unit and the electrode delivery unit during the gripping operation, and shorten the time required for the gripping operation of the electrode. On the other hand, when the block body is moved to the other side, the gripping portions of the two claw members approach each other and the electrodes are firmly fixed by the gripping portions, so that the electrodes may unexpectedly fall off from the gripping unit. You can definitely prevent it from slipping.

In the eighth aspect of the invention, since the electrode storage unit is installed at a predetermined position, even if the electrode stored in the electrode storage unit is lost due to repeated electrode replacement work, the operator can still place the grip unit on the transport unit. The electrode storage unit can be filled with electrodes while the stationary spot welding gun is moving between the stationary spot welding gun and the electrode storage unit. Therefore, the operator can perform the filling work of the electrodes in the area where the gripping unit is not moving, so that the work can be performed safely. In addition, since the operator can fill the electrode while the grip unit is supplying the electrode to the stationary spot welding gun, there is no need to stop the production line for the reason of filling the electrode, resulting in high production efficiency. It can be an electrode supply device for spot welding.

In the ninth invention, when the gripping unit for gripping the electrode is brought closer to the stationary spot welding gun by the transfer unit, the electrode removing unit also approaches the stationary spot welding gun. Therefore, the electrode held by the holding unit can be supplied to the stationary spot welding gun immediately after the electrode is removed from the stationary spot welding gun by the electrode removal unit, and the electrode replacement work can be performed efficiently. .

1 is a perspective view of a spot welding electrode supply device according to Embodiment 1 of the present invention; FIG. FIG. 2 is a view equivalent to FIG. 1 showing a state in which the electrode storage unit is removed from the electrode delivery unit; 1 is a perspective view of an electrode storage unit according to Embodiment 1 of the present invention; FIG. 1 is a perspective view of an electrode storage unit and an electrode delivery unit according to Embodiment 1 of the present invention; FIG. 1 is a perspective view of a grasping unit according to Embodiment 1 of the present invention; FIG. FIG. 5 is a cross-sectional view taken along line VI-VI of FIG. 4, showing a state immediately before the electrodes are taken out from the electrode storage unit by the electrode delivery unit; FIG. 7 is a view after FIG. 6 showing a state in the middle of taking out the electrodes from the electrode storage unit by the electrode delivery unit; FIG. 8 is a view after FIG. 7 showing the state immediately after the electrodes are taken out from the electrode storage unit by the electrode delivery unit; FIG. 9 is a view after FIG. 8 and showing the state immediately before the gripping unit is transported to the stationary spot welding gun by the transport unit; FIG. 3 is a view corresponding to FIG. 3 according to Embodiment 2 of the present invention. FIG. 4 is a view corresponding to FIG. 4 according to Embodiment 2 of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail based on the drawings. It should be noted that the following description of preferred embodiments is merely exemplary in nature.

<<Embodiment 1 of the invention>>
FIG. 1 shows a spot welding electrode supply device 1 according to Embodiment 1 of the present invention. This electrode supply device 1 is arranged in an automobile production line, and is capable of supplying an electrode 10 to a shank G1 of a stationary spot welding gun G. As shown in FIG.

The electrode supply device 1 includes an electrode storage unit 2 capable of storing a plurality of electrodes 10, an electrode delivery unit 3 arranged on the side of a production line and fixed to a support (not shown), and an arm tip A1 of an industrial robot A. and a pair of gripping units 5 attached to both sides of the electrode removal unit 4. The electrode storage unit 2, as shown in FIG. It is designed to be detachably attached to the

As shown in FIG. 3, the electrode storage unit 2 includes a substantially square tube-shaped storage case 21 that extends linearly in the horizontal direction. , and a cover member 23 that closes the upper open portion of the case body 22 .

The inner portion of the case main body 22 forms a linear housing passage R1 (electrode housing portion) capable of housing a plurality of electrodes 10. At one end of the housing passage R1, an electrode outlet 20 communicating with the housing passage R1 is provided. is provided.

The accommodation passage R1 can accommodate the electrodes 10 in a straight line in a direction perpendicular to the central axis thereof, and in a state in which a plurality of fitting recesses 10a that are fitted to the tip of the shank G1 are arranged side by side so as to open in the same direction. It's becoming

A rectangular opening 22a communicating with the housing passage R1 is formed on one side wall of the case body 22 on the electrode outlet 20 side.

On the other hand, a slit 22b extending linearly along the longitudinal direction of the case main body 22 is formed in the vertical middle portion of the other side wall of the case main body 22, and the slit 22b communicates with the housing passage R1.

The longitudinal dimension of the cover member 23 is shorter than the longitudinal dimension of the case main body 22, and one longitudinal end of the case main body 22 is opened upward to form a shank entrance 23a connected to the electrode outlet 20. It has become.

A lever member 24 extending along the longitudinal direction of the case body 22 is arranged outside one side wall of the case body 22 and at a position corresponding to the opening 22a.

The lever member 24 can swing around a swing shaft (not shown) extending in the vertical direction provided in the middle thereof. It is adapted to enter the accommodation passage R1.

A coil spring (not shown) is arranged between one side wall of the case main body 22 and the lever member 24, and the biasing force of the coil spring swings the lever member 24 to one side.

When the lever member 24 is swung to one side by the urging force of a coil spring (not shown), the distal end side enters the housing passage R1 through the opening 22a and blocks part of the electrode outlet 20, while the other side is not shown. When it swings to the other side against the urging force of the coil spring, the tip side is separated from the housing passage R1 to open the electrode outlet 20 .

A pressing mechanism 25 extending along the extension direction of the accommodation passage R1 is attached to the other end of the accommodation case 21 in the longitudinal direction.

The pressing mechanism 25 presses one or a plurality of electrodes 10 accommodated in the accommodation passage R1 toward the electrode outlet 20 by means of a coil spring (not shown). When one of the accommodated electrodes 10 is taken out, the remaining electrodes 10 in the accommodation passage R1 are moved toward the electrode extraction port 20 side.

As shown in FIG. 2, the electrode delivery unit 3 includes a mounting bracket 31 having a U-shaped cross section, and the mounting bracket 31 has a mounting space S1 open to the front, rear, and one side. there is

The mounting bracket 31 allows the electrode storage unit 2 to be inserted into the mounting space S1 from one side thereof, and the electrode storage unit 2 to be fixed by a pair of index plungers P1.

As shown in FIG. 4 , a block-shaped guide member 30 corresponding to the electrode outlet 20 of the electrode housing unit 2 fixed to the mounting bracket 31 is fixed to the lower front portion of the mounting bracket 31 .

The upper surface of the guide member 30 is formed with a groove 30a extending along the longitudinal direction of the electrode storage unit 2 and having a cross-sectional shape corresponding to the tip side shape of the electrode 10. The area farthest from the outlet 20 constitutes the electrode standby position W1 of the present invention.

A rectangular plate-shaped base plate 32 whose front and back faces are oriented in the longitudinal direction of the electrode housing unit 2 is fixed to the upper portion of the mounting bracket 31, and an electrode is placed in the center of the base plate 32 as shown in FIGS. A first through-hole 32a and a second through-hole 32b, which penetrate along the longitudinal direction of the storage unit 2, are arranged vertically.

As shown in FIG. 4, a first air cylinder 33 (first fluid pressure cylinder) whose cylinder center line extends along the longitudinal direction of the electrode housing unit 2 is fixed to the lower part of the back surface of the base plate 32. A first piston rod 33a of the cylinder 33 passes through the second through hole 32b and extends to the front side of the base plate 32 so as to be able to expand and contract.

A cylindrical stopper 34a is fixed to the upper part of the front surface of the base plate 32 so as to correspond to the first through hole 32a. A pair of thin guide rods 34b having a circular cross section are provided.

A connecting member 34c that connects the two guide rods is fixed to the tip of both the guide rods 34b, and a fastening bolt 34d is attached to the center of the connecting member 34c so that the head side protrudes between the two guide rods 34b. It is

Between the base plate 32 and the connecting member 34c, a moving block 34e is provided that straddles both guide rods 34b. It is designed to move

A slide hole 34f penetrating vertically is formed in the center of the moving block 34e, and a round bar-shaped slide body 35 is fitted in the slide hole 34f so as to be vertically movable forward and backward.

The slide body 35 is in a posture in which the distal end portion having a tapered outer peripheral surface is positioned downward, and as shown in FIG. It has become.

A pair of protrusions 35a protruding in a direction orthogonal to both the center line of the slide body 35 and the direction of expansion and contraction of the first piston rod 33a are provided on the outer peripheral surface of the intermediate portion of the slide body 35 across the center line. It is

Below the moving block 34e, a guide plate 35b having a U-shaped cross section that opens toward the base plate 32 and extending downward is fixed to the lower surface of the moving block 34e so as to surround the slide body 35. Each side wall is formed with a vertically extending slit-shaped inner guide hole 35c for guiding each projection 35a provided on the slide body 35 when the slide body 35 moves forward or backward in the vertical direction.

A cam member 36, which is short in the vertical direction and has a rectangular tube shape, is provided below the moving block 34e and is fixed to the tip of the first piston rod 33a.

At positions corresponding to the inner guide holes 35c of the guide plate 35b in the cam member 36, there extend linearly inclined so as to be positioned gradually in the advancing direction of the slide body 35 as the first piston rod 33a moves in the contracting direction. A pair of slit-shaped outer guide holes 36a (first guide holes) are formed, and each outer guide hole 36a guideably supports each projection 35a passing through each inner guide hole 35c.

Each protrusion 35a provided on the slide body 35 and each outer guide hole 36a in the cam member 36 constitute the cam mechanism 12 of the present invention, and the cam mechanism 12 interlocks with the extension operation of the first piston rod 33a. While the slide body 35 is advanced by the first piston rod 33a, the slide body 35 is retracted in conjunction with the contraction operation of the first piston rod 33a.

Specifically explaining the operation of the cam mechanism 12, as shown in FIGS. 6 and 7, when the first piston rod 33a of the first air cylinder 33 extends while the slide body 35 is in the original position, each projection 35a Guided by the inner guide holes 35c from one end of each outer guide hole 36a to the other end, the slide body 35 advances and the tip of the slide body 35 moves toward the electrode of the accommodation passage R1 in the accommodation case 21. It is designed to be inserted into a fitting recess 10 a of the electrode 10 accommodated at a position corresponding to the outlet 20 .

When the first piston rod 33a is further extended while the tip of the slide body 35 is inserted into the fitting recess 10a, as shown in FIG. The first piston rod 33 a presses the slide body 35 so that the electrode 10 into which the tip of the slide body 35 is inserted in the maintained state passes through the electrode outlet 20 . As the moving block 34e is guided by the guide rods 34b until the moving block 34e contacts the fastening bolt 34d, the slide body 35 moves in the extension direction of the first piston rod 33a. , and guided by the guide member 30 to the electrode standby position W1.

Further, when the first piston rod 33a is contracted while the electrode 10 is positioned at the electrode standby position W1, as shown in FIG. By being guided from one end to the other end, the slide body 35 is retracted so that the tip thereof is disengaged from the fitting recess 10a of the electrode 10. As shown in FIG.

When the first piston rod 33a is further contracted, each protrusion 35a is maintained at one end of each outer guide hole 36a, and the first piston rod 33a pulls the slide body 35. As the moving block 34e is guided by the guide rods 34b until it contacts the cylindrical stopper 34a, the slide body 35 moves in the contraction direction of the first piston rod 33a and returns to its original position.

After that, by repeating the expansion and contraction of the first piston rod 33a of the first air cylinder 33, the electrodes 10 are sequentially taken out from the electrode storage unit 2 and delivered to the electrode standby position W1.

An air-type cushion cylinder 37 (brake mechanism) is fixed to the upper portion of the back surface of the base plate 32 so that the center line of the cylinder extends along the longitudinal direction of the electrode housing unit 2 .

A rod portion 37a of the cushion cylinder 37 passes through the first through hole 32a and the cylindrical stopper 34a and extends telescopically toward the front side of the base plate 32, and its tip is fixed to the moving block 34e.

When the first piston rod 33a of the first air cylinder 33 is extended, the cushion cylinder 37 applies a load to the slide body 35 that is smaller than the force applied to the slide body 35 by the extension operation of the first piston rod 33a. While it is generated in the contraction direction of the first piston rod 33a via the moving block 34e, when the first piston rod 33a of the first air cylinder 33 is contracted, it is applied to the slide body 35 by the contraction operation of the first piston rod 33a. It is configured to generate a load smaller than the force on the slide body 35 in the extending direction of the first piston rod 33a via the moving block 34e. Therefore, when the first piston rod 33a extends with each protrusion 35a positioned at one end of each outer guide hole 36a, the load applied to the slide body 35 by the cushion cylinder 37 causes the slide body 35 to move to the first position. Each protrusion 35a is smoothly guided by each outer guide hole 36a without moving in the extending direction of the first piston rod 33a together with the first piston rod 33a, so that the slide body 35 advances. On the other hand, when the first piston rod 33a contracts with each protrusion 35a positioned at the other end of the outer guide hole 36a, the load applied to the slide body 35 by the cushion cylinder 37 causes the slide body 35 to move to the first position. Each protrusion 35a is smoothly guided by the outer guide hole 36a without moving in the contraction direction of the first piston rod 33a together with the piston rod 33a, so that the slide body 35 retreats. By providing the cushion cylinder 37 in this way, the sliding body 35 can be smoothly advanced and retracted by the expansion and contraction of the first piston rod 33a.

As shown in FIGS. 1 and 5, the gripping unit 5 includes a substantially rectangular plate-shaped support member 51 whose front and back surfaces face the front and rear directions of the electrode removal unit 4. The support member 51 includes a support member A housing recess 51a is formed in the width direction of the support member 51 and is open to the front surface of the support member 51. As shown in FIG.

A second air cylinder 52 (second fluid pressure cylinder) is fixed to the center of the back surface of the support member 51 , and the second piston rod 52 a of the second air cylinder 52 is accommodated in a recess formed on the back surface of the support member 51 . It passes through a communication hole (not shown) that communicates with 51a and extends to the front side of support member 51 so as to be able to expand and contract.

A central portion of a block body 53 extending in the same direction as the width direction of the support member 51 is fixed to the tip of the second piston rod 52a. It is designed to

A pair of claw members 54 extending along the cylinder center line C1 is arranged on the front side of the support member 51, and both claw members 54 are arranged side by side with the cylinder center line C1 as a boundary.

Gripping portions 54a are formed on surfaces facing each other on the distal end side of both claw members 54. The gripping portions 54a are recessed in a substantially V shape in a plan view.

On the other hand, the base end side of each claw member 54 is housed in the housing recess 51a of the support member 51, and the support member 51 moves the base ends of both claw members 54 so that both claw members 54 can approach and separate from each other. side is rotatably supported by a rotating shaft 54b.

A hollow portion 54c that opens to the other claw member 54 side and the opposite side is formed in the middle portion of the claw member 54, and each end portion of the block body 53 is formed in the hollow portion 54c of each claw member 54. It's designed to get in.

Each wall part separated from the end of the block body 53 in the middle of the claw member 54 has a slit-shaped slit extending linearly inclined so as to approach the other claw member toward the base end side. Opening/closing guide holes 54d (second guide holes) are formed respectively.

On the other hand, at each end of the block body 53, a pin 53a extending in a direction crossing both the expansion/contraction direction of the second piston rod 52a and the longitudinal direction of the block body 53 is attached so as to pass through the block body 53. , the ends of the pins 53a protruding from the block 53 are movably fitted in the opening/closing guide holes 54d.

Then, as shown in FIGS. 6 to 9, when gripping the electrode 10 at the electrode standby position W1 with the claw members 54, the electrode 10 is positioned between the grasping portions 54a of the claw members 54, and When the block member 53 is moved to one side and the opening/closing guide holes 54d of the claw members 54 guide the pins 53a to one end side, the two claw members 54 approach each other, and the electrode 10 is fitted by this approaching operation. It is configured to be gripped in a posture that does not block the opening of the recess 10a. On the other hand, when releasing the electrode 10 gripped by both claw members 54, the block body 53 is moved to the other side, and each open/close guide hole 54d of each claw member 54 guides the pin 53a to the other end side. The pawl members 54 are arranged to move away from each other and release the electrode 10 by this moving away.

As shown in FIGS. 1 and 2, the electrode removal unit 4 includes a plate-like casing 41 having a thickness that forms a substantially rectangular shape in plan view. An upper opening 41a and a lower opening 41b are formed in a substantially rectangular shape.

A third air cylinder 42 is attached to the rear side of the casing 41 on the other side in the width direction.

Between the upper opening hole 41a and the lower opening hole 41b inside the casing 41, a substantially doughnut-shaped rotating body 43 having a center of rotation which can be rotated forward and backward by the expansion and contraction of the third air cylinder 42 extends vertically is attached. The electrode 10 to be fitted to the shank G1 of the welding gun G is arranged at the center of the rotating body 43, and the rotating body 43 is rotated and twisted with respect to the shank G1 so that the electrode 10 is separated from the shank G1. there is

The industrial robot A is a general 6-axis vertical articulated robot, and is adapted to transport the gripping unit 5 to the electrode supply position X1 of the stationary spot welding gun G. As shown in FIG.

Next, the operation of supplying the electrodes 10 to the stationary spot welding gun G using the electrode supply device 1 according to Embodiment 1 of the present invention will be described in detail.

First, in a state in which both claw members 54 are separated from each other as in one gripping unit 5 in FIG. It is moved to the electrode standby position W1, and as shown in FIG.

Next, the first air cylinder 33 of the electrode delivery unit 3 is operated to extend the first piston rod 33a. Then, the cam member 36 is pushed by the first piston rod 33a in its extension direction, but the cushion cylinder 37 applies a load in the contraction direction of the first piston rod 33a. It is smoothly guided from one end to the other end, and along with this, as shown in FIG. It is inserted into the fitting recess 10a of the electrode 10 housed in position.

Next, the first piston rod 33a tries to extend further while the tip of the slide body 35 is inserted into the fitting recess 10a of the electrode 10, so that each projection 35a moves toward the other end of each outer guide hole 36a. , the moving block 34e is guided by both guide rods 34b until it comes into contact with the fastening bolt 34d, and accordingly the slide body 35 moves in the extending direction of the first piston rod 33a. Then, due to the movement of the electrode 10 accompanying the movement of the slide body 35, the lever member 24 of the electrode housing unit 2 swings to the other side against the urging force of the coil spring (not shown) to open the electrode outlet 20, thereby opening the electrode. 10 passes through the electrode outlet 20 and is sent to the electrode standby position W1 while being guided by the guide member 30. As shown in FIG.

When the electrode 10 passes through the electrode outlet 20, the plurality of other electrodes 10 arranged side by side in the accommodation passage R1 are pressed by the pressing mechanism 25 and move toward one end of the accommodation passage R1.

Then, when the lever member 24 swings to one side by the urging force of a coil spring (not shown), the tip portion of the lever member 24 blocks part of the electrode outlet 20, and the next electrode 10 can be taken out. .

After that, when the electrode 10 reaches the electrode standby position W1, the block body 53 of the second air cylinder 52 of the gripping unit 5 is moved. Then, both claw members 54 are rotated so as to approach each other, and the electrode 10 at the electrode standby position W1 is gripped by both gripping portions 54a.

Then, the first air cylinder 33 of the electrode delivery unit 3 is operated to contract the first piston rod 33a. Then, the cam member 36 is pulled by the first piston rod 33a in its retracting direction, but the cushion cylinder 37 applies a load in the extending direction of the first piston rod 33a, so that each projection 35a is positioned at the other end of each outer guide hole 36a. As shown in FIG. 9, the slide body 35 is moved back and its tip part is disengaged from the fitting recess 10a of the electrode 10 positioned at the electrode standby position W1. .

After that, the first piston rod 33a tries to contract further, so that each protrusion 35a is maintained at one end of each outer guide hole 36a, and then the moving block 34e comes into contact with the cylindrical stopper 34a. The slide member 35 is guided by the guide rods 34b until it reaches its original position.

When the gripping unit 5 grips the electrode 10 at the electrode standby position W1, the industrial robot A transports the electrode removing unit 4 and the pair of gripping units 5 to the stationary spot welding gun G as shown in FIG.

After the rotating body 43 of the electrode removing unit 4 is brought close to the electrode 10 attached to the shank G1 of the stationary spot welding gun G, the electrode 10 is arranged at the center of the rotating body 43 and the rotating body 43 is rotated. The electrode 10 fitted to the shank G1 is twisted and removed from the shank G1.

Thereafter, the electrode 10 gripped by the gripping unit 5 is moved to the electrode supply position X1, and the shank G1 is fitted into the fitting recess 10a of the electrode 10, thereby completing the replacement of the electrode 10. FIG.

As described above, according to Embodiment 1 of the present invention, since the opening of the fitting recess 10a of the electrode 10 gripped by the gripping unit 5 is open at the electrode standby position W1, the gripping unit 5 can be used for stationary spot welding. By moving it to the gun G, the electrode 10 can be attached to the shank G1 of the welding gun G while being held by the holding unit 5 .

In addition, since the electrode storage unit 2 is installed at a predetermined position, even if the electrode 10 stored in the electrode storage unit 2 is lost due to repeated electrode replacement work, the operator can keep the grasping unit 5 from the industrial robot. While moving between the stationary spot welding gun G and the electrode storage unit 2 at A, the work of filling the electrode storage unit 2 with the electrode 10 can be performed. Therefore, since the operator can perform the filling work of the electrode 10 in the region where the grip unit 5 is not moving, the work can be performed safely. In addition, since the operator can fill the electrode 10 while the holding unit 5 is supplying the electrode 10 to the stationary spot welding gun G, there is no need to stop the production line for the reason of filling the electrode 10. , the electrode supply device 1 for spot welding with good production efficiency can be obtained.

Further, the operation of taking out the electrode 10 from the storage case 21 by the electrode delivery unit 3 can be performed by only two simple operations, that is, the forward movement of the slide body 35 and the extension movement of the first piston rod 33a by the first air cylinder 33. become. Therefore, the structure of the electrode delivery unit 3 becomes simple, and the occurrence of failure of the device can be suppressed.

Further, in the electrode delivery unit 3, the electrode 10 taken out from the storage case 21 can be delivered to the electrode standby position W1 by using the extension operation of the first piston rod 33a for taking out the electrode 10 from the storage case 21. Therefore, there is no need to separately prepare a facility only for feeding the electrode 10 taken out from the storage case 21 to the electrode standby position W1, and the structure can be made at a reduced cost.

Further, since the sliding body 35 is moved back and forth by the expansion and contraction of the first piston rod 33a of the first air cylinder 33, the equipment is provided only for making the slide body 35 move back and forth along its center line. is no longer necessary, and the structure can be made at a lower cost.

In addition, the electrodes 10 housed in the housing case 21 can be sequentially moved to the electrode standby position W1 only by the expansion and contraction of the first piston rod 33a in the first air cylinder 33, and the equipment is simple and low cost. can be

In the gripping unit 5, when the block 53 is moved to one side by the second air cylinder 52, the gripping portions 54a of the claw members 54 are separated from each other. 5, the electrode 10 can be easily guided between the gripping portions 54a of the claw members 54. As shown in FIG. Therefore, it is possible to increase the speed of the grasping unit 5 and the electrode delivery unit 3 during the grasping operation, and shorten the time required for the grasping operation of the electrode 10 . On the other hand, when the block body 53 is moved to the other side, the gripping portions 54a of the claw members 54 approach each other and the electrode 10 is firmly fixed by the gripping portions 54a. 10 can be reliably prevented from falling off unexpectedly.

In addition, since not only the gripping unit 5 but also the electrode removing unit 4 are attached to the arm tip A1 of the industrial robot A, the gripping unit for gripping the electrode 10 to the stationary spot welding gun G by the industrial robot A. When 5 is brought closer, the electrode removal unit 4 also comes closer. Therefore, immediately after the electrode 10 is removed from the stationary spot welding gun G by the electrode removing unit 4, the electrode 10 gripped by the gripping unit 5 can be supplied to the stationary spot welding gun G, and the electrode 10 can be replaced. can be done efficiently.

In the first embodiment of the present invention, the industrial robot A is used as the transport unit that transports the gripping unit 5. However, other types of transport machines may be used for transport.

Further, in Embodiment 1 of the present invention, the opening/closing guide holes 54d formed in the claw members 54 of the grip unit 5 are slit-shaped, but may be groove-shaped.

<<Invention Embodiment 2>>
10 and 11 show an electrode storage unit 2 and an electrode delivery unit 3 of an electrode supply device 1 according to Embodiment 2 of the present invention. In Embodiment 2, the storage case 21 in the electrode storage unit 2 has a shape corresponding to the male tapered electrode 10, and the cushion cylinder 37 in the electrode delivery unit 3 is combined with the first air cylinder 33 and the mounting bracket 31. The only difference from the first embodiment is that it is structured to be positioned between and that the gripping unit 6 is provided on the guide member 30, and the other operations of each mechanism are the same as those of the first embodiment. Therefore, only the parts different from the first embodiment will be described below.

On the base end side of the male tapered electrode 10 of Embodiment 2, a fitting portion 10 b having a cylindrical shape with an outer diameter smaller than that of the tip end side of the electrode 10 is aligned with the central axis of the electrode 10 . The electrode 10 is attached to the shank G1 of the spot welding gun G by externally fitting the shank G1 of the spot welding gun G into the fitting portion 10b.

A pair of guide walls 30b extending along the extension direction of the guide member 30 are provided on the sides of the upper portion of the guide member 30 of the second embodiment so as to face each other.

On the inner surface of one guide wall 30b, the side surface of the electrode 10 guided by the guide member 30 is pressed against the inner surface of the other guide wall 30b to hold the electrode 10 in a state in which a wide space is provided around the fitting portion 10b. The guide walls 30b and the cushion pins 30c constitute the grasping unit 6 of the present invention.

The operation of the electrode delivery unit 3 when supplying the male taper type electrode 10 to the spot welding gun G using the electrode supply device 1 according to the second embodiment of the present invention is the gripping of the electrode 10 at the electrode standby position W1. Since it is the same as the first embodiment except for the method, detailed description is omitted.

As described above, according to the second embodiment of the present invention, since the opening of the fitting recess 10a of the electrode 10 gripped by the gripping unit 6 at the electrode standby position W1 is open, the male taper electrode 10 can be spotted. By bringing the shank G1 of the welding gun G close to the electrode standby position W1, the electrode 10 can be attached to the shank G1 without contacting other electrodes 10. - 特許庁

In Embodiments 1 and 2 of the present invention, the sliding body 35 is advanced and retracted by the cam mechanism 12 comprising the protrusion 35a and the outer guide hole 36a, but other types of cam mechanisms may be used. good too.

Further, in Embodiments 1 and 2 of the present invention, the outer guide hole 36a of the cam mechanism 12 has a slit shape, but it may have a groove shape.

Further, in Embodiments 1 and 2 of the present invention, the first air cylinder 33 and the second air cylinder 52 are used as the fluid pressure cylinders. good.

INDUSTRIAL APPLICABILITY The present invention is suitable, for example, as a spot welding electrode supply device capable of supplying electrodes when exchanging the electrodes of a spot welding gun used in a factory or the like.

REFERENCE SIGNS LIST 1 spot welding electrode storage unit 2 electrode storage unit 3 electrode delivery unit 4 electrode removal unit 5 gripping unit 6 gripping unit 10 electrode 10a fitting recess 12 cam mechanism 20 electrode outlet 21 storage case 30 guide member 30a groove 33 First air cylinder (first fluid pressure cylinder)
33a first piston rod 35 slide body 35a projection 36a outer guide hole (first guide hole)
37 Cushion cylinder (brake mechanism)
52 Second air cylinder (second fluid pressure cylinder)
53 Block body 53a Pin 54 Claw member 54a Grip portion 54d Guide hole for opening/closing (second guide hole)
A Industrial robot (conveyance unit)
G Stationary spot welding gun G1 Shank R1 Housing passage (electrode housing)
W1 Electrode standby position X1 Electrode supply position

Claims (9)

A spot welding electrode supply device capable of supplying a spot welding electrode,
an electrode storage unit installed at a predetermined position and capable of storing a plurality of electrodes;
an electrode delivery unit that sequentially takes out the electrodes from the electrode storage unit and delivers them to an electrode standby position;
a gripping unit capable of gripping the electrode at the electrode standby position in a posture that does not block the opening of the fitting recess into which the tip of the shank of the spot welding gun is fitted ;
The electrode housing unit includes a housing case having an electrode housing part capable of housing a plurality of electrodes with the fitting recesses opening in the same direction, and an electrode outlet communicating with the electrode housing part,
The electrode delivery unit is configured to be able to advance and retreat along the center line, and when advanced, the distal end portion is inserted into the fitting recess of the electrode accommodated at a position corresponding to the electrode outlet of the electrode accommodation portion. and is configured to press the slide body so that the electrode, into which the tip of the slide body is inserted, passes through the electrode outlet and is sent out to the electrode standby position. Electrode supply device for spot welding. In the spot welding electrode supply device according to claim 1 ,
The electrode delivery unit has a piston rod that can extend and contract in a direction orthogonal to the center line of the slide body, and when the piston rod is extended , the slide body is pushed and delivered to the electrode standby position. A spot welding electrode supply device comprising a first fluid pressure cylinder . In the spot welding electrode supply device according to claim 2,
The electrode delivery unit includes a guide member having a groove that guides the electrode, which passes through the electrode outlet and is further pressed by the first fluid pressure cylinder, from the electrode outlet to the electrode standby position. An electrode supply device for spot welding characterized by: In the spot welding electrode supply device according to claim 2 or 3,
The electrode delivery unit is characterized by comprising a cam mechanism that advances the slide body in conjunction with the extension action of the piston rod and retreats the slide body in conjunction with the contraction action of the piston rod. Electrode supply device for spot welding. In the spot welding electrode supply device according to claim 4,
The cam mechanism is provided on the outer peripheral surface of the slide body, and includes a projection that protrudes in a direction perpendicular to both the center line of the slide body and the direction of expansion and contraction of the piston rod, and a projection that protrudes in the direction of contraction of the piston rod. A spot welding electrode characterized by comprising a first guide hole having a groove shape or a slit shape that gradually extends in the forward direction of the slide body and supports the projection so as to be able to guide it. feeding device. In the spot welding electrode supply device according to claim 5,
When the piston rod is extended, the electrode delivery unit causes the slide body to generate a load smaller than the force applied to the slide body by the extension movement of the piston rod in the contraction direction of the piston rod. It is characterized by comprising a brake mechanism that, when contracting the piston rod, generates a load on the slide body in the extension direction of the piston rod that is smaller than the force applied to the slide body by the contraction movement of the piston rod. Electrode supply device for spot welding. In the spot welding electrode supply device according to any one of claims 1 to 6,
The gripping unit includes a second fluid pressure cylinder that moves the block along the center line of the cylinder, and a second fluid pressure cylinder that extends along the center line of the cylinder. A pair of claw members having a grip portion, and a support member pivotally supporting the base end sides of the claw members so that the claw members can be moved toward and away from each other,
A second guide hole having a groove shape or a slit shape inclined so as to approach the other claw member as it goes toward the proximal end of the claw member is formed in the middle part of the claw member,
pins projecting from the block body are movably fitted into the second guide holes of the claw members,
When the electrodes at the electrode standby position are gripped by the claw members, the electrodes are positioned between the gripping portions of the claw members, the block body is moved to one side, and each of the second electrodes is moved to one side. When the guide holes guide the pins toward one end, the two claw members approach each other, and this approaching action grips the electrode, while releasing the electrode gripped by the two claw members. , the block body is moved to the other side and the second guide holes guide the pins to the other end side, so that the claw members are separated from each other, and the electrode is released by this separating operation. An electrode supply device for spot welding characterized by: In the spot welding electrode supply device according to any one of claims 1 to 7,
The spot welding gun is stationary,
An electrode supply device for spot welding, comprising a transport unit for transporting the holding unit to a position for supplying the electrode to the spot welding gun. In the spot welding electrode supply device according to claim 8,
The spot welding unit is characterized in that an electrode removal unit capable of removing the electrode fitted to the shank of the spot welding gun from the shank by twisting the electrode with respect to the shank is further attached to the transfer unit. Welding electrode supply device.