JPH0341896Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is used in the technical field of welding of metals, etc., and particularly relates to welding robots.

(Conventional technology) Automatic welding equipment used includes:
Conventionally, there are robots that combine a material holding robot for feeding the workpiece into the welding zone and a welding robot placed in the welding zone, and dedicated robots that are specially manufactured to have workpiece holding and welding functions. There is a machine.

(Problems that the invention aims to solve) However, these equipments are designed to automate welding processes, and in the former case, the equipment cost and installation area increase in proportion to the number of robots, and in the latter case, the equipment cost and installation area increase in proportion to the number of robots. Since the workpiece is manually fed directly into the welding zone, there are problems such as the need for protective measures.

The present invention has been developed in consideration of the above-mentioned problems of the conventional technology.
To provide a welding robot capable of holding materials and welding with one robot.

(Means for solving the problems) Means for solving the above problems of the present invention are as follows:
A workpiece that has been positioned by an appropriate means is held up to the workpiece mounting member for welding, and is attached to the lower end of the vertical rotation axis of the distal end of a multi-jointed arm that is movably supported on a base. In this case, a work holder is connected to the work holder, a torch is connected to a horizontal rotation shaft provided above the work holder via a holding arm, and the work holder is connected to a bracket fixed to the vertical rotation shaft at the tip. a disk pivotally supported by the bracket and having a position fixing means interposed therebetween; a workpiece pressing means connected to the disk so as to be able to adjust its inclination angle; and a disk connected to the workpiece pressing means. The present invention is characterized by comprising a workpiece holding member whose rotation is restrained, and a cover member which is loosely fitted to the lower end of the workpiece and covers the non-welded portion of the workpiece.

(Function) The effect of the above means is that the positioned workpiece is held by the workpiece holding member and placed on the part to be welded on the workpiece mounting member, and the workpiece is pressed against the workpiece mounting member by the workpiece pressing means and the workpiece holding member. After tack welding is performed, the workpiece pressing means and the workpiece holding member are retracted, and the cover member covers the non-welded portion of the workpiece.
When main welding is performed in this state, spatter flying toward the workpiece is blocked by the cover member.

If the workpiece has an inclination angle, by rotating the cylinder holding flange of the workpiece pressing means with respect to the disk of the workholder, the axis of the workholder coincides with the axis of the workpiece, so that the inclination angle can be adjusted. It is possible to hold workpieces with

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

The welding robot 1 shown in FIGS. 1 and 2 is
An elevating body 3 is vertically movably provided on a base 2 erected on a floor F, and a multi-joint arm 4 extending in the horizontal direction is supported on the elevating body. The multi-jointed arm extends from the base rotation shaft 5 attached to the elevating body 3 to the first
It is formed by sequentially connecting an arm 6, an intermediate vertical rotation shaft 7, a second arm 8, and a tip vertical rotation shaft 9, and a work holder 10 is attached to the lower end of the tip vertical rotation shaft. An arc welding torch 12 is connected via a holding arm 13 to a horizontal rotation shaft 11 provided above the work holder. The welding robot 1 has a built-in known storage device, control device, etc., and has a working range 14.
A workpiece supply means 15 and a workpiece attachment member conveyance means 16 are attached therein, and the workpiece W in this example is a shaft of a roller applied to a forklift, etc., and the workpiece attachment member B performs a relative expansion and contraction operation via the rollers. It is a must to do so.

In FIG. 3, the work holder 10 has a bracket 1 fixed to the lower end of the tip vertical rotation shaft 9.
7, a disk 19 which is pivotally supported by the bracket and has a position fixing means 18 interposed between it and the bracket 17, and a workpiece pressing means 20 which is connected to the disk so that its inclination angle θ can be adjusted. an electromagnet connected to the workpiece pressing means and whose rotation is restrained;
It consists of a work holding member 21 such as a permanent magnet, and a cover member 22 that is loosely fitted to the lower end of the work holder and covers the non-welded portion of the work W.

That is, in the bracket 17, a main body 23 having an L-shaped cross section is fastened to the tip end vertical rotation shaft 9 by a bolt 24, and a bearing box 25 fixed to the lower part of the main body 23 by an appropriate means accommodates bearings 26, 26. has been done.

The disk 19 has a support shaft 27 protruding from the center.
is pivotally supported by the bearing 26, and an inclined hole 28 whose axis _C2 is inclined by 1 _degree with respect to the axis C1 of the support shaft 27 is bored in the lower surface.

The position fixing means 18 is used to set a welding start point during tack welding of the workpiece W, and to connect the bracket 17 and the disk 19 during actual welding. Engagement holes 29, 29 are drilled, and a cylinder 30 is fixed to the bracket 17 by appropriate means.
and a locking pin 31 that is engaged with and disengaged from the engagement hole 29 by the cylinder.

The workpiece pressing means 20 is for pressing the workpiece W against the workpiece mounting member B by the workpiece holding member 21 when tack welding the workpiece W, and is a cylinder holding flange connected to the upper end of the cylinder 32. 33 has a cylinder 3 on its upper surface.
2, that is, an inclined protrusion 33a is formed in which the axis _C2 is inclined by 1 degree with respect to the axis _C3 of the workpiece holding member 21, and the inclined protrusion 33a is fitted into the inclined hole 28 to form an outer circumference. The cylinder holding flange 33 is rotated 180° to hold the workpiece W (solid line in Figure 3), which is fixed with, for example, three tightening bolts 34 and formed at an inclination angle θ of 2°. By aligning the axial center _C3 of the member 21 with the axial center _C1 of the disk 19, it is possible to adapt to the holding state of a normal-shaped workpiece W (dashed line in FIG. 3).

On the other hand, a guide sleeve 35 is fitted to the work holding member 21 which is detachably attached to the lower end of the piston rod 32a, and the guide sleeve has a lower end that slides into the inner cavity of the work W for alignment. The workpiece holding member 21 is prevented from rotating by forming a conical surface portion 35a and by loosely fitting stepped through holes 35b, 35b drilled in the outer peripheral portion into guide bars 36, 36 protruding downward from the cylinder 32. It is configured so that it can be raised and lowered while being restrained.

The cover member 22 is for preventing spatter from adhering to the non-welded parts during main welding of the workpiece W, and is formed in a cylindrical shape and is attached to the guide sleeve 35.
It is loosely fitted around the outer periphery of the workpiece W and always covers the non-welded part of the workpiece W by its own weight, and a flange part 22a is formed on its upper edge to prevent it from falling.

The workpiece supply means 15 sequentially supplies and positions the workpieces W to required positions P within the working range 14 of the welding robot 1, and as shown in FIGS. 4 to 6, the workpieces W are placed on the floor F. Fixed frame 4
1, a driving side shaft 42 and a driven side shaft 43 are arranged, and a double row sprocket 42 is fixed to each shaft.
Endless chains 44, 44 are wound around a, 43a, respectively, and attachments 44a are attached to the endless chains at equidistant positions, and the endless chains are provided so as to be slidable on a chain guide 45. A chain conveyor 47 is constructed by installing a positioning plate 46 on each of the conveyors.

The positioning plate 46 has guide holes 46a and 46b concentrically drilled with steps for fitting workpieces W of different shapes (two types in this example).
A groove-shaped mark alignment portion 46c is formed on the upper surface of the front side (right side in FIG. 4) of the guide hole. For example, by matching the mark M formed on the thin wall part of the flange of the workpiece W having an inclination angle θ to the mark matching part, the delivery to the welding robot 1 and the setting of the inclination direction at the mounting position of the workpiece mounting member B can be performed accurately. It is beginning to be practiced.

On the other hand, the protruding end of the drive side shaft 42 and the output shaft 48a of the drive means 48 such as a motor with an electromagnetic clutch
A transmission mechanism 49 formed by winding an endless chain 49c around a small sprocket 49a and a large sprocket 49b is interposed, and the driving means 48 is a one-rotation cam for intermittently moving the positioning plates 46 one by one. and a miro switch (both not shown) are installed.

Furthermore, a supply end positioning mechanism 50 is provided at the front end (right end in FIGS. 4 and 5) of the chain conveyor 47. The supply end positioning mechanism positions the positioning plate 46 at a required position P within the operating range 14 of the welding robot 1.
The push-back cylinder 51 is fixed to the tip of the pedestal 41, and the fixed guide roller 52a and the pressing guide roller 5 are provided on both sides of the front end of the chain conveyor 47.
2b, and a receiving roller 53 that supports the positioning plate 46 at a position in front of the chain guide 45, and moves the positioning plate 46 to enter the required position P at the front end of the chain conveyor 47. The amount is set to be slightly excessive, and the push-back cylinder 5 from the approach position
After positioning it at the required position P in step 1, press the side clamping tool 5.
It is configured to be fixed at 2.

The workpiece attachment member conveying means 16 intermittently conveys the workpiece attachment member B and also transports the welding robot 1.
The part to be welded of the workpiece mounting member B is fixed so as to face the welding zone Z within the operating range 14 of the workpiece, and as shown in FIGS.
A plurality of drive rollers 56 are arranged at equal intervals on the top,
A stopper 57 for stopping the conveyance end position of the workpiece mounting member B is provided at a position below the space between the drive rollers 56 in the welding zone Z so as to be movable up and down with respect to the position above the drive roller 56;
The stopper includes an elevating cylinder 58 fixed to the pedestal 55, a parallel rod 59 connected to the elevating cylinder, a tubular roller 60 pivoted to the upper end of the parallel rod, and a raised/lowered cylinder 58 fixed to the pedestal 55. Parallel rod 5
Rod guide 6 that slidably supports the middle part of 9.
It consists of 1.

On the other hand, a positioning mechanism 62 is provided on the beam 55a at the side end of the pedestal 55. a frame 64 that moves, a driving-side clamping member 65, a driven-side clamping member 66, a pinion 67, a clamping cylinder 68, and a position adjustment cylinder 69 for adjusting the position of the frame 64 in the transport direction. It is made up of. That is, the frame 64 is provided with a driving side guide portion 64b extending from above the base portion 64a in a direction intersecting the conveyance direction, and a cylinder holding portion 64c is continuously provided below from the driving side guide portion to form a substantially reverse groove shape. The base portion 64a is formed on the guide rail 6.
3 and is slidably fitted to the frame 5.
A piston rod 69a of a position adjustment cylinder 69 fixedly attached to the drive side guide portion 64b is connected
The drive-side clamping member 65 is slidably fitted to the
A piston rod 68a of a clamping cylinder 68 is connected to the cylinder holding portion 64c.

Further, a driven side guide portion 64d is located below the driving side guide portion 64b.
between the rack part 66a of the driven side holding member 66, which is fixed to the frame 64 so as to be parallel to the above, and is slidably fitted into the driven side guide part 64d, and the rack part 65a of the drive side holding member 65. A clamping cylinder 68 is interposed with a pinion 67 that meshes with both.
By expanding and contracting, the claws 65b and 66b provided at the lower end of each clamping member are configured to clamp the workpiece mounting member B in an openable and closable manner.

Next, the operation of the above embodiment will be explained.

In advance, the workpiece W is inserted into the guide holes 46a and 46b of each positioning plate 46 of the workpiece supply means 15 (if the workpiece has an inclination angle θ, its purpose M
(matching the mark matching portion 46c), the workpiece numbers are registered in the storage device of the welding robot 1, and the frontmost workpiece W is positioned at the required position P. The operation of the welding robot 1 is performed by signals from a control device based on information registered in a storage device.

First, the multi-joint arm 4 of the welding robot 1 rotates from its free position, and the work holder 10 moves to an appropriate position directly above the work W (work W
has an inclination angle θ, manually rotate the cylinder holding flange 33 to remove the workpiece holding member 21.
The inclination of is adapted to the inclination angle θ. ) Next, the cylinder 32 is driven downward to bring the guide sleeve 35 into sliding contact with the inner cavity of the workpiece W, while the workpiece holding member 21 holds the workpiece W by magnetic attraction.

On the other hand, the workpiece attachment member conveying means 16 is driven to cause the welded portion of the workpiece attachment member B to enter an appropriate position in the welding zone Z, and the position is fixed by the positioning mechanism 62.

Subsequently, the multi-joint arm 4 of the welding robot 1 performs a rising motion and a turning motion to adapt the workpiece W held by the workpiece holding member 21 to the part to be welded on the workpiece mounting member B, and then the workpiece W is moved into the cylinder. The locking pin 31 is maintained strongly pressed against the workpiece mounting member B by the downward drive of the cylinder 32, and the locking pin 31 is moved to the engagement hole 29 by the upward drive of the cylinder 30 to the position fixing means 18.
depart from. Here, since the torch 12 can be rotated by the tip vertical rotation axis 9, it can be rotated at two locations on the workpiece W (one location at the solid line position in FIG.
After performing tack welding of 5 mm to 10 mm and turning the torch 12 further 180 degrees to return it to its original position, the cylinder 30 is driven downward to lock the locking pin 31 in the engagement hole 29. and said cylinder 3
2, the workpiece holding member 21 is detached above the workpiece W.

Thereafter, main welding is performed around the entire circumference of the workpiece W by the torch 12 which is rotated by the tip vertical rotation shaft 9. At this time, since the non-welded portion of the workpiece W is completely covered with the cover member 22, there is no risk of adhesion of spatter. The workpiece mounting member B that has completed the welding process is released from the fixation by the positioning mechanism 62 and carried out to the next process by the drive roller 56, and the subsequent workpieces W are moved in the same manner as described above with respect to the workpiece mounting member B that is sequentially conveyed. Each welding process is performed in the same order.

(Effects) With the above configuration, the welding robot can
Since the workpiece holding operation and welding operation are automatically performed on the stand, not only can equipment costs and installation space be reduced, but the structure is simple and operation is extremely easy, and the workpiece can be handled manually. This has the advantage that safety is significantly improved because the welding zone is not directly supplied during operation.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, in which Fig. 1 is a plan view of the welding robot, Fig. 2 is a front view thereof, and Fig. 3 is an enlarged front view of the work holder and torch, partially shown in cross section. Fig. 4 is a plan view of the work supply means, Fig. 5 is a front view thereof, and Fig. 6 is a - of Fig. 4.
A sectional view of the positioning plate along the line, FIG. 7 is a plan view showing the main part of the workpiece attachment member conveyance means,
8 is a front view of the stopper taken along the line - in FIG. 7, and FIG. 9 is a front view of the positioning mechanism taken along the line - in FIG. 7. DESCRIPTION OF SYMBOLS 1...Welding robot, 2...Base, 3...Elevating body, 4...Multi-joint arm, 9...Tip vertical rotation axis, 10...Work holder, 11...Horizontal rotation axis,
12...Torch, 13...Holding arm, 15...
Work supplying means, 16...Work mounting member conveying means, 17...Bracket, 18...Position fixing means, 19...Disc, 20...Work pressing means, 21...Work holding member, 22...Cover member, 50... Supply end positioning mechanism, 62... Positioning mechanism, W... Work, B... Work mounting member, θ... Inclination angle, P... Necessary position.

Claims (1)

[Scope of utility model registration request] The workpiece is positioned by appropriate means,
A work holder is connected to the lower end of the vertical rotation shaft of the distal end of the multi-jointed arm, which is held up to the top of the workpiece mounting member and is welded to the base so that it can be raised and lowered. A torch is connected via a holding arm to a horizontal rotation shaft provided above a work holder, and the work holder is pivotally supported by a bracket fixed to a vertical rotation shaft at a tip end,
and a disk having a position fixing means interposed between it and the bracket, a workpiece pressing means connected to the disk so as to be able to adjust its inclination angle, and a workpiece holding device connected to the workpiece pressing means and restrained from rotating. 1. A welding robot comprising: a member; and a cover member that is loosely fitted to the lower end of a work holder and covers a non-welded part of the work.