JP2003231032A - Work positioning clamping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To position and clamp various kinds of works by one kind of positioning clamping device. <P>SOLUTION: This positioning clamping device comprises a plurality of conical positioning members 15 respectively inserted into a plurality of pin insertion holes 14 formed on a work W for positioning the work, abutting parts (seat ring) respectively mounted on a rear end part of each positioning member 15 and seated on a peripheral edge part of each pin insertion hole, a clamp member located inside of the positioning member (positioning pin 15) at a lowered position, and displaced to a clamping position of a holding face at the circumference of the pin insertion holes 14 of the work W at a raised position, and a base (mounting base, unit base 3a) for mounting the clamp member, and the positioning member can be raised and lowered to the base. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work positioning clamp device, and more particularly to an improvement thereof.

[0002]

2. Description of the Related Art As a conventional positioning clamp device of this type, for example, as disclosed in Japanese Utility Model Registration No. 594529, a J-shaped clamp member is provided in a slot of a cone-shaped positioning member. There is known a device in which the tip end (grasping part) of the clamp member is projected and retracted inside and outside the slot by rotating the clamp member as it moves up and down. When the clamp member is pulled upward, the tip end of the clamp member is rotated upward while being protruded laterally from the inside of the slit, and when the clamp member is pushed downward, Is attached to the positioning member like a slider crank so that the front end portion thereof is stored inside the slot from the outside of the slot. Further, the tip of the positioning pin has a cone shape whose diameter is gradually reduced toward the tip for automatic alignment, and the rear end of the positioning pin is abutted against the peripheral edge of the insertion hole. The pedestal ring is integrally provided, and the abutting portion whose diameter is expanded with respect to the tip of the positioning pin and the tip of the clamp can hold the peripheral edge of the insertion hole of the work. There is.

[0003]

Therefore, a plurality of the positioning clamp devices are attached to the substrate so as to correspond to the insertion holes of the workpiece, and the clamp members of each positioning clamp device are held in the state of being pulled back to the upper side. Meanwhile, when each positioning pin is inserted into the insertion hole on the work side by descending the substrate, the work is positioned by the cone-shaped tip portion, and subsequently, when each clamp member is pulled up while maintaining the positioning state, The work is integrated with the positioning clamp. Therefore, if the positioning clamp device is attached to the robot arm via the substrate, handling of the work by the operation of the robot arm can be realized, but the peripheral portion of the insertion hole in which each pin insertion hole of the work is provided. Even if the (positioning clamp part) is flat with respect to the abutting part of each positioning member, the height from the reference surface of the work to each peripheral edge may be different for each work. Therefore, in order to be able to use the positioning clamp device for all works, the position of the positioning pin, the length of the clamp member, and the position of the abutting portion must be changed for each work. There is.

Therefore, there arises a technical problem to be solved in order to provide a positioning clamp device capable of absorbing the height difference between the peripheral portions of the pin insertion holes with respect to the reference surface of the work. The purpose is to solve this problem.

[0005]

The invention according to claim 1 is
A plurality of cone-shaped positioning members that are respectively inserted and positioned in a plurality of pin insertion holes opened in the work, and an abutting portion that is provided at the rear end of each positioning member and that is seated on the peripheral edge of each pin insertion hole. A positioning member that displaces inside the positioning member at a rising position and a clamping position on a gripping surface around a pin insertion hole of the work at a descending position, and a substrate to which the clamping member is attached. Provided is a work positioning clamp device in which a member is provided to be movable up and down with respect to the substrate. Each of the positioning members can move up and down independently of each other, and the rear end portion of each of the positioning members abuts on the peripheral edge of the pin insertion hole when the insertion of the positioning member into the pin insertion hole is completed. Since the portion is provided, the positioning clamp can be performed even if there is a step in the insertion direction of the pin insertion hole (the height direction of the workpiece) between the peripheral portions (positioning clamp portions) of the pin insertion hole.

According to a second aspect of the present invention, a plurality of cone-shaped positioning members that are respectively inserted into the plurality of pin insertion holes formed in the work and positioned, and the pin insertion holes that are provided at the rear ends of the respective positioning members. An abutting portion that sits on the peripheral portion of the hole, and is displaced inside the positioning member at the lowered position,
At a raised position, it has a clamp member that is displaced to a clamp position on a gripping surface around the pin insertion hole of the work, and a substrate to which the clamp member is attached, and each positioning member can be moved up and down on the substrate via a slide table. Provided is a work positioning clamp device in which mounting and connecting the slide table and the substrate in a vertical direction of the slide table through a damper that elastically expands and contracts.
Each positioning member can move up and down independently of each other via the slide table, and at the rear end of each positioning member, when the positioning member is completely inserted into the pin insertion hole, the positioning member is attached to the peripheral portion of the pin insertion hole. Since the seating abutting portion is provided, the workpiece can be clamped even if there is a step in the insertion direction of the pin insertion hole between the peripheral portions of the pin insertion hole. Further, the damper buffers the impact force when the abutting portion is abutted against the peripheral edge portion of the pin insertion hole.

In the inventions of claims 1 and 2, one substrate (unit substrate) may be shared as the substrate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an indirect spot welding system to which the present invention is applied will be described in detail below with reference to FIGS. 1 to 9. FIG. 4 shows the overall configuration of the indirect spot welding system. As shown in the figure, in the robot indirect spot welding system 1, a material handling unit (hereinafter referred to as a material handling unit) 3 is attached to the tip of a robot arm 2, and a work W is clamped to the material handling unit 3. A plurality of clamp units 4 are provided. In each clamp unit 4, when the positioning pins 15 of at least two clamp units 4 are exposed in the pin insertion holes 14 of the work W, the other positioning pins 15 are exposed in the other corresponding pin insertion holes 14. As described above, each is mounted on the unit substrate 3a of the material handling unit 3. The spot welding portion 5 in the indirect welding includes a power feeding unit 6, a rectifying transformer 7, and a spot welding device body 8, and the power feeding unit 6 is connected to the spot welding device body 8 via the rectifying transformer 7. Three
3 is a ground connection terminal, 34 is an earth stand,
The grounding connection terminal 33 is inserted into the grounding clamp 39 attached to the material handling unit 3 and clamped.

FIG. 1 is an enlarged perspective view of the clamp unit 4, FIG. 2 is an enlarged sectional view schematically showing the structure of the clamp unit 4, and FIG. 3 is a positioning pin 1 of the clamp unit 4.
FIG. 5 is an enlarged perspective view of a main part of FIG. As shown in FIG. 1, the clamp unit 4 has a mounting substrate (substrate) 11 mounted on the material handling unit 3 with bolts 10 as a main body. Mounting board 11
A slide table 13 is supported on the lower surface of the work piece 1 through a first cylinder means (damper) 12, and the positioning pin 1 is inserted into the pin insertion hole 14 (see FIG. 2) of the work W.
5 is attached to the lower part of the slide table 13. The slide table 13 is vertically movably engaged with a guide groove 16a of a guide 16 extending vertically downward from the lower surface of the mounting substrate 11, and moves vertically along the guide groove 16a. The first cylinder means 12 is a cylinder 12a serving as a main body, a piston rod 12b slidably fitted in the cylinder 12a, and is housed in the cylinder 12a. The cylinder 12a and the piston rod 12b are always connected to each other. , A return spring (not shown) that elastically contacts and applies an elastic force to the both, the base of the cylinder 12a is attached to the unit substrate 3a of the material handling unit 3 via the attachment substrate 11, and the piston The tip of the rod 12b is attached to the table surface 13a of the slide table 13 via the bracket 9. A gas spring may be used as the first cylinder means (damper) 12. In addition, the second cylinder means 18 is attached to the lower surface of the attachment substrate 11 so that the slide table 13 can be stopped. The second cylinder means 18 is composed of, for example, a pneumatic cylinder or a hydraulic cylinder in which a cylinder rod is reciprocally housed, and is attached so that the tip surface of the piston rod 18a faces the table surface 13a of the slide table 13. To be A pressing member 18b is integrally attached to the tip end of the piston rod 18a, and the table surface 13a of the slide table 13 is knurled to increase the frictional force and the biting force with respect to the pressing member 18b. To be done. The pressing member 18b
Is made of an elastic material such as urethane or chloroprene having a high friction coefficient. Therefore, when the second cylinder means 18 is expanded and the table surface 13a of the slide table 13 is pressed by the pressing member 18b, the frictional force and the biting force generated between the pressing member 18b and the table surface 13a cause The slide table 13 stops. Note that, in FIG. 1, the second cylinder means 18 is contracted to the maximum, and the pressing member 18b is separated from the table surface 13a.

The mounting board 11 and the slide table 13 are connected to each other by connecting terminals 35 and 36 and an earth cable 37.
And the connection terminal 35 is connected to the ground terminal 38 of the material handling unit 3 (see FIG. 6). As a result, the ground electrode is connected to the clamp member 22 that constitutes each clamp mechanism 20. In this case, since the plurality of clamp members 22 also serve as earth clamps, a clamp dedicated to earth is not required, and work time for earth connection can be saved. further,
Since each clamp unit 4 has a plurality of current collecting points and current is distributed to each clamp mechanism 20 to flow the work W, the current density of the gripping surface of the work W does not increase, and the work W at the time of spot welding does not increase. Generation of heat at the gripped portion is prevented, and appearance defects of the work W due to spot welding are prevented.

As shown in FIG. 2, the positioning pin 15 is provided.
Protrudes from the lower surface of the slide table 13, and the tip portion has a cone shape in which the diameter is successively reduced toward the tip for inserting the work W into the pin insertion hole 14.

Referring to FIGS. 2 and 3, the positioning pin 15 has a slot 19 extending from the rear end to the vicinity of the front end.
Is formed, and a clamp mechanism (slider crank mechanism) 20 for holding the work W is stored in the slot 19. As shown in FIG. 2, the clamp mechanism 20 is
A V-shaped link lever 21 rotatably supported by a support shaft 25, a clamp member 22 connected to one arm 21a of the link lever 21 via a pin R, and a clamp member 22 provided on the clamp member 22. And a guide shaft 24 that guides the opening 23.

The guide shaft 24 has a cam-shaped opening 23.
Also, the link lever 21 is axially supported by the positioning pin 15 penetrating the slot 19 and is supported by the slide table 13 via the support shaft 25. The other arm 21b of the link lever 21 is connected to the piston rod 26a of the third cylinder means 26 attached to the slide table 13 (see FIG. 1).

When the clamp member 22 is pushed down by the counterclockwise rotation of the link lever 21, the cam-shaped opening 23 causes the clamp member 22 to rotate clockwise and, conversely, the link lever 21. When the clamp member 22 is pulled back upward by rotating the clamp member 22 in the clockwise direction, the clamp member 22 is formed in an oblique and arcuate shape so as to rotate in the counterclockwise direction. In addition, the upper end of the opening 23 of the opening 23 is pushed down by the clamp member 22 so that the guide shaft 2
4, the entire clamp member 22 is accommodated in the slit 19, and the upper end of the clamp member 22 is gripped at the position where the lower end of the opening 23 comes into contact with the guide shaft 24 when the clamp member 22 is pulled up. While projecting the portion 22a from the window of the slot 19 to the outside, the portion 22a is rotated counterclockwise to be displaced to the clamp position.
The lower gripping surface is formed so as to be pressed from below. The “clamping position” is the peripheral portion of the pin insertion hole 14 of the work W, and the flat ring surface 27a of the pedestal ring (abutting portion) 27 of the positioning pin 15 and the tip of the clamp member 22 are gripped. It means the position where it is gripped by the portion 22a. Further, at the rear end portion of the positioning member 15, the grip portion 22 at the tip of the clamp member 22 at the clamp position is provided.
A pedestal ring (abutting portion) 27 for gripping the work W with a is provided. Therefore, by storing the clamp member 22 by the third cylinder means 26, the positioning pin 15 can be inserted into the pin insertion hole 14 of the work W described above. Further, the positioning pin 15 is attached to the pin insertion hole 1
4, the work W (for example, the inner panel after hemming of the outer panel and the inner panel of the automobile door) is pulled back by pulling back the clamp member 22 by the third cylinder means 26.
Of the holding portion 22a and the flat ring surface 2 of the pedestal ring 27
It is gripped by 7a.

FIG. 5 shows a control circuit for detecting the insertion degree of the positioning pin 15 and controlling the operation of the clamp member 22.
The control circuit mainly includes a pressure detection passage 29 that opens to the ring surface 27a of the pedestal ring 27, a pressure detection sensor 30 that detects the pressure inside the pressure detection passage 29, and a pressure inside the pressure detection passage 29. When the value exceeds the predetermined value, a signal is output to a control device (not shown) that controls the third cylinder means 26 and the robot arm 2, assuming that the air ejection port 29a by the gripping surface of the work W is sealed. And a signal output circuit 31. The signal output circuit 31
Is electrically connected to an extension / contraction switching circuit 32 for switching the extension / contraction of the third cylinder means 26 to switch the clamp member 22 between the holding position and the holding release position. The circuit 32, when the signal is output from the signal output circuit 31, the clamp member 2
2 gripping portion 22a and the flat ring surface 2 of the pedestal ring 27
In order to grip the gripping surface (clamping position) of the work W with 7a, a switching signal for contraction is output to the drive circuit of the third cylinder means 26 to contract. When the drive circuit of the third cylinder means 26 is a hydraulic circuit, the expansion / contraction switching circuit 32 is for the hydraulic circuit, and when it is a pneumatic circuit.
A switching signal is output to each of the pneumatic pressure switching circuits.

A plurality of clamp units 4 shown in FIG.
When the workpiece W is clamped by the expansion / contraction switching circuit 32, the extension / contraction switching circuit 32 is first output when the signal output circuit 31 outputs a signal indicating that each air ejection port 29a is sealed.
A signal for switching to contraction is output to the drive circuit of the third cylinder means 26 of each clamp unit 4 to contract the cylinder means 26. As a result, the clamp member 22 is rotated in the counterclockwise direction while being raised, and the gripping portion 22a of each clamp member 22 and the flat ring surface 27a of the pedestal ring 27 allow the upper gripping surface (clamping position) of the work W to be clamped. ) Is grabbed. The signal output circuit 31 is a pressure switch or a meter relay,
The contraction switching circuit 32 is composed of a sequence circuit or an electric circuit such as a microcomputer.

FIG. 6 is an overall configuration diagram of the material handling unit 3 that clamps and transports the work W, and FIG. 7 is a side view of the material handling unit 3 that shows a state in which the work W can be transported after being clamped. In the work W, the pin insertion holes 14 are arranged in an equilateral triangle, and the unit substrate 3a of the material handling unit 3 has a board of three clamp units 4 so that each positioning pin 15 can be inserted into each pin insertion hole 14. 11 are attached in an equilateral triangular arrangement. In addition, without using the substrate 11, the first cylinder means 12, the second cylinder means 18, the unit board 3a of the material handling unit 3,
By directly attaching the slide table 13,
One of the substrate 11 and the unit substrate 3a may be omitted.

Next, the handling and operation of the material handling unit 3 according to this embodiment will be described with reference to FIGS. 1, 4, and 6. First, in order to enable the slide table 13 to be lifted and lowered to be lifted, a signal for switching to the contracted position is output to the drive circuit of the second cylinder means 18 of each clamp unit 4. By outputting this switching signal, the pressing member 18 is pushed from the table surface 13 a of each slide table 13.
When b is removed, the slide table 13 of each unit 4
Is moved to the maximum lowered position by the urging force (elastic force) of the first cylinder means 12. Next, the tip end of each positioning pin 15 is moved to the work W by the robot arm 2 moving the material handling unit 3 back and forth, left and right, and up and down.
To the insertion position of each pin insertion hole 14 (see FIG. 4). In this state, the material handling unit 3 is lowered, and the positioning pins 15 of all the clamp units 4 attached to the material handling unit 3 are inserted into the pin insertion holes 14 of the work W. Pin insertion hole 1 for the reference surface of the work
When there is a step in the height direction between the peripheral edge portions of No. 4, the corresponding positioning pins are provided from the peripheral edge portion of the pin insertion hole 14 on the higher side to the peripheral edge portion of the pin insertion hole 14 on the lower side with respect to the reference surface of the work W. The pedestal rings 27 of 15 are seated one after another.

When the pedestal ring 27 is seated on the peripheral edge of the pin insertion hole 14 and the peripheral edge of the pin insertion hole 14 is pressed by the urging force of the first cylinder means 12 via the pedestal ring 27, Blow-through of the detection gas from the passage of the pressure detection passage 29 is blocked, and the pressure in the pressure detection passage 29 is increased by the pressure supplied to the pressure detection passage 29. On the other hand, the signal output circuit 31 constantly outputs the detected value of each passage internal pressure output from the pressure detection sensor 30 that detects the passage internal pressure of each pressure detection passage 29 and the comparison value stored in advance. , And a switching signal indicating that the air ejection port 29a by the gripping surface of the work W is sealed until all the detection values of the pressure detection passage 29 detected by the pressure detection sensor 30 exceed the comparison values. Does not output, nor does it output a signal to the controller of the robot arm 2. Therefore, the pedestal ring 2 of all the positioning pins 15
The entire material handling unit 3 continues to be lowered until 7 is seated on the peripheral edge portions of all the pin insertion holes 14 of the work W. When all the detected values of the internal pressure of each pressure detection passage 29 detected by the pressure detection sensor 30 exceed the comparison value (set value), the signal output circuit 31 causes the extension / contraction switching circuit 32. A signal indicating that the air ejection port 29a by the gripping surface of the work W is sealed, and the extension / contraction switching circuit 32 outputs a signal for switching to the contraction to each third cylinder means 26. To do. By this switching, the gripping portion 22a at the tip of the clamp member 22 stored inside the slot 19 of each positioning pin 15 rotates upward while being displaced outward (counterclockwise in the illustrated example), The pedestal ring 27 of each positioning pin 15 and the flat ring surface 27 of the pedestal ring 27
With a, the peripheral surface of each pin insertion hole 14 is gripped by the gripping surface of the work W in the thickness direction. Then slide table 1
In order to stop No. 3, a switching signal is output to the drive circuit of each second cylinder means 18 to switch the second cylinder means 18 to extension, and the pressing member 18b is joined to the table surface 13a of each slide table 13. . As described above, the table surface 13a of the slide table 13 is knurled to increase the frictional force and the biting force with the pressing member 18b, and the pressing member 18b has a friction coefficient of urethane, chloroprene, or the like. Since it is made of a high rubber elastic body, the slide table 13 is prevented from moving up and down. As a result, each slide table 13 can be integrated with the material handling unit 3 and the robot arm 2, and can be moved (handled) to a predetermined position by the lower movement of the robot arm 2 up, down, left and right, and forward and backward. Secondary processing by other devices is possible without rattling.

In the above-described embodiment of the present invention, the three clamp units 4 are arranged in an equilateral triangle, but the arrangement is the same on both the work W side and the material handling unit 3 side. However, the shape is not limited to the triangular shape. For example, an isosceles triangular shape, another triangular shape, or three or more clamp units 4 may be used to form a polygonal arrangement. Further, the position of the positioning pin 15 of each clamp unit 4 and the work W
When the center of gravity is taken into consideration in the position of the pin insertion hole 14 of FIG. In addition, when the earth clamp is also used, it is natural that a current path is formed by an insulating material such as rubber. As described above, the present invention can be variously modified without departing from the gist of the present invention, and the present invention naturally extends to the modified invention.

As described above, in the present embodiment, all the pin insertion holes 14 are made to correspond to the steps of the pin insertion holes 14 in which the pin insertion holes 14 of the positioning pins 15 of the work W are provided. After inserting the positioning pins 15, the clamp members 22 incorporated in the respective positioning pins 15 are operated and clamped. However, each pin insertion hole 14
If there is a difference in height in the peripheral portion of the pin insertion hole 14 in which the ridges are formed and there is a step, as described above, the pedestal rings 27 of all the positioning pins 15 are simultaneously seated on the corresponding peripheral portions. It is not possible. Therefore, until the pedestal ring 27 of the final positioning pin 15 is seated on the peripheral edge of the corresponding pin insertion hole 14, the pedestal ring 27 of the first positioning pin 15 is seated on the peripheral edge of the pin insertion hole 14. During this period, the urging force of the first cylinder means 12 acts, so when the thickness of the peripheral portion is thin and the strength is low, the peripheral portion of the pin insertion hole 14 is provided with Deflection corresponding to the biasing force occurs. The bending is caused by the pedestal ring 27 and the gripping portion 22 of each clamp member 22.
It is corrected with a and causes damage such as accidental scratches and wrinkles.

Therefore, when the strength of the work W side is low with respect to the urging force (elastic force) of the first cylinder means 12,
Positioning is not performed by directly using the pin insertion hole 14 of the work W as described above, but the positioning clamp is performed by another process. That is, the position of each positioning pin 15 in the height direction is adjusted in advance, and all the positioning pin insertion holes 14 are adjusted.
However, by inserting all the positioning pins 15 at the same time to complete the positioning, this kind of problem is solved. Of course, each positioning pin 15 is inserted into each pin insertion hole 14.
When inserting, each slide table 13 is locked by extending the second cylinder means 18. By doing so, the urging force (elastic force) of the first cylinder means 12
Does not act on the peripheral portion of the pin insertion hole 14, and the magnitude of the pressing force on the peripheral portion of each positioning pin 15 is 1 with respect to the magnitude of the pressing force acting on the entire material handling unit 3 by the robot arm 2. Since it will be reduced to / 3, the occurrence of bending of the peripheral portion of each pin insertion hole 14 is prevented,
It is possible to prevent the peripheral edge portion of the pin insertion hole 14 from being damaged or wrinkled due to the bending.

Specifically, for adjusting the height of each positioning pin 15 with respect to each pin insertion hole 14, a positioning base T shown in FIG. 8 is used. As shown in FIG. 8, the robot arm 2 is arranged within the turning range. Further, the positioning table T is installed so that its upper surface is parallel to the horizontal plane. When adjusting the height of each positioning pin 15 of the material handling unit 3, the second cylinder means 1 of all the clamp units 4 is adjusted.
8 is contracted to release the lock of the slide table 13, and is moved to the maximum descending position by the urging force of the first cylinder means 12. By rotating the material handling unit 3 up, down, left and right, and front and back by the robot arm 2, the specific positioning pin 15 is moved above the positioning base T and pushed down while facing the upper surface of the positioning base T. The seating of the tip end surface of the positioning pin 15 on the upper surface of the positioning table T is detected by a sensor. The position of the upper surface of the positioning table T, the height from the reference surface of the work W to the peripheral edge of each pin insertion hole 14, and each pin insertion hole mounted on the mounting table on which the work W is mounted. Although the height from the peripheral edge of 14 to the flat ring surface 27a of the pedestal ring 27 of each positioning pin 15 of the material handling unit 3 is different from each other, it is known that the completion of the insertion of the positioning pin 15 is detected. From the height position, the positioning pin is further lowered by the height from the reference surface of the work W to the pin insertion hole 14, and the second cylinder means 18 is switched to extension at that position to move the slide table 13 up and down. When is stopped, the work of adjusting the height position with respect to the specific positioning pin 15 is completed. Next, the other positioning pin 15 is positioned. In this case, since the positioning of the positioning pin 15 serving as the reference has been completed, the above positioning work is repeated with the position of the positioning pin 15 as the reference, and the position of the positioning pin 15 of the other clamp unit 4 in the height direction. Are sequentially determined. The position of the upper surface of the positioning table T,
The height from the reference surface of the work W to the peripheral portion of each pin insertion hole 14 and each pin insertion hole 14 of the work W mounted on a mounting table (not shown) on which the work W is mounted. The height from the peripheral edge of each of the positioning pins 15 of the material handling unit 3 to the flat ring surface 27a of the pedestal ring 27 is constant for each positioning pin 15 and is known in advance. The positioning pin 1 is provided for each clamp unit 4 without using the height position of the positioning pin 15 obtained by the positioning of the pin 15 as a reference.
5 may be positioned. Therefore, even when the strength of the work W is low and the strength of the pin insertion hole 14 is low, the positioning clamp device according to the present embodiment can be used to perform the positioning clamp of each work W.

FIG. 9 is an explanatory view showing the structure of a position confirmation device 50 for confirming the height position of a specific positioning pin 15 and using it as a reference for another positioning pin 15 with a simple structure. As shown in the drawing, the position confirmation device 50 is installed on the side of the positioning table T, and when the robot arm 2 descends, the positioning pin 15 is positioned after the positioning is completed.
A check bar 51 for confirming the position in the height direction is provided so as to be able to move up and down while bringing the tip end surface of the above into contact with and lowering it. The check bar 51 is always pushed back upward by the return spring 52. When confirming the position, the lowering of the robot arm 2 is temporarily stopped at a stroke shorter by a predetermined stroke a than the lowering stroke of the positioning pin 15 with respect to the work W determined by the robot arm 2 and the positioning table 50, and then, predetermined. The first stop position is checked at the first stop position and the second stop position is checked at the next stop position by stopping again at the position where the predetermined stroke b is added to the stroke a. In this case, when the position of the positioning pin 15 is correctly set by the robot arm 2 and the positioning base 50 when confirming the position, the proximity sensor 53 checks the above-mentioned first-stage check position. so,
The lower end of the check bar 51 is located above the sensing range above the proximity sensor 53 by a predetermined distance (the same distance as the predetermined stroke a), and at the second check position, the lower surface of the check bar 51 is The proximity sensor 53 is arranged so as to be below a sensing range above the proximity sensor 53 by a predetermined distance (the same distance as the predetermined stroke b) b. By disposing the proximity sensor 53 in this way, the descending operation of the robot arm 2 at the time of confirming the position is divided into two stages, and the positioning pin 15
If the position is confirmed, it is possible to determine whether or not the positioning is proper by the ON and OFF signals of the proximity sensor 53 in the checks in the first step and the second step. That is, when an ON signal is output from the proximity sensor 53 in the first-stage check, the height position of the positioning pin 15 by the robot arm 2 and the positioning base T is set to the plus side (overshoot), and the setting is made. It is possible to detect that it is defective, and when the OFF signal is output (when the ON signal is not output), it can be estimated that the setting was proper in the first stage check. it can.
Then, the authenticity is confirmed in the second check stage. That is, in the first-stage check, the proximity sensor 53 detects the OF
Even if the F signal is output, this state is
It is not possible to distinguish whether or not the lower end of the check bar 51 is too far away from 3, but when the OFF signal is output from the proximity sensor 53 in this second-stage check, positioning with the robot arm 2 is performed. The setting of the height position of the positioning pin 15 by the platform T is made to the minus (too much retracted) side, and it is possible to determine that the setting is defective. When the ON signal is output from the proximity sensor 53, it can be determined that the height direction of the positioning pin is correctly set. Thus, according to the position confirmation device 50 described above, the positioning pin 50
Since the position confirmation can be detected by one proximity switch 53, it is possible to contribute to cost reduction.

[0025]

As described above, according to the first aspect of the invention, since the positioning pin can be moved up and down, the peripheral edge where the pin communicating hole for inserting the positioning pin with respect to the reference surface of the work is formed. Even if the heights of the parts are different, the workpiece positioning clamp can be performed without changing the positioning pins. Therefore, it is possible to perform positioning clamps for various works with a kind of positioning clamp device.

Further, in the invention according to claim 2, since the damper alleviates the impact force when the abutting portion of the positioning pin is seated on the peripheral portion of the pin insertion hole of the work, the positioning clamp device side, the work. It is possible to prevent damage to both sides.

[Brief description of drawings]

FIG. 1 is an enlarged perspective view showing an embodiment of a clamp unit constituting a work positioning clamp device according to the present invention.

FIG. 2 is an enlarged cross-sectional view schematically showing a state of gripping a clamp member built in a positioning pin according to the embodiment of the present invention.

FIG. 3 is an enlarged perspective view of a main portion of a positioning pin (positioning member) on the tip end side according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a schematic configuration of an indirect spot welding system using a robot according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a control circuit for detecting an insertion degree of a positioning pin with respect to a work according to the embodiment of the present invention.

FIG. 6 is an explanatory view showing an arrangement of pin insertion holes of a work and an inserted state of each positioning member of the material handling unit according to the embodiment of the present invention.

FIG. 7 is an explanatory side view showing a transportable state after clamping according to the embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a configuration of a positioning base used for adjusting the height position of each positioning pin.

FIG. 9 is an explanatory diagram showing the configuration of a position confirmation device for confirming the adjustment of the height position of a positioning pin.

[Explanation of symbols]

3a Unit board (board) 11 Mounting board (board) 12 First cylinder means (damper) 13 slide table 14 pin insertion hole 15 Positioning pin (positioning member) 18 Second cylinder means (damper) 22 Clamp member 27 Pedestal ring (butt part) W work

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koji Nishikawa             1907 Hirata Town, Suzuka City, Mie Prefecture Honda Motor Co., Ltd.             Suzuka Works Co., Ltd. (72) Inventor Hideki Ishikawa             4-16 Gotoyama, Azai, Ama prefecture             Kojima Koki Co., Ltd. F-term (reference) 3C016 CA04 CB03 CC02 CC04 CE05

Claims (2)

[Claims] 1. A plurality of cone-shaped positioning members that are respectively inserted into and positioned in a plurality of pin insertion holes formed in a work, and seated on the peripheral edge of each pin insertion hole provided at the rear end of each positioning member. The abutting portion, the clamp member that is displaced inside the positioning member at the lowered position, and the clamp position that is displaced to the clamp position on the gripping surface around the pin insertion hole of the work at the raised position, and the clamp member is detachably attached. And a substrate, and the positioning member is provided so as to be movable up and down with respect to the substrate. 2. A plurality of cone-shaped positioning members that are respectively inserted into and positioned in a plurality of pin insertion holes opened in the work, and seated on the peripheral edge of each pin insertion hole provided at the rear end of each positioning member. An abutting portion, a clamp member that is displaced inside the positioning member at the lowered position, and is displaced to the clamp position on the gripping surface around the pin insertion hole of the work at the raised position; and a substrate to which the clamp member is attached. Each of the positioning members is attached to the substrate in a vertically movable manner via a slide table, and the slide table and the substrate are connected to each other in a vertical direction of the slide table via an elastically expandable / contractible damper. Workpiece positioning clamp device.