JPS6233038B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for loading and unloading jigs for objects to be welded, the main purpose of which is to improve the operating rate of welding robots.

Conventionally, there has been a welding robot which is equipped with a main body including a torch and a fixture for attaching the workpiece including a mounting plate, and which automatically performs welding by appropriately controlling the relative position of the torch and the mounting plate using a control device. The work of loading and unloading workpieces into and out of workpiece fixtures is carried out by attaching a jig for fixing workpieces to the mounting plate in advance, and performing manual work each time automatic welding work is completed for each workpiece. Accordingly, installation tools and cargo handling machines such as cranes were used as appropriate.

However, such loading/unloading operations require a considerable amount of time to position, fix, and remove the objects to be welded from the jig, resulting in a decrease in the operating rate of the welding robot.

In view of the above-mentioned circumstances, the present invention is provided with a jig fixing clamp device on the mounting plate, and two standby positions located on the left and right outside of the movable range of the mounting plate near the welding object fixture. A pair of left and right carts are provided so that they can traverse between each jig and at least one jig loading/unloading position defined within the movable range. Equipped with a box for mounting tools, one trolley waits at the standby position with the jig empty during welding work on the robot, while the other trolley is in the standby position and does not cover the jig on the box. The welding material can be attached and removed, and after welding is completed, the empty cart is reciprocated to a jig loading/unloading position, followed by the other loaded truck being reciprocated to a jig loading/unloading position; At each loading and unloading position, the jig fixing clamp device and the jig transfer mechanism work together to fix and release the jig between the mounting plate and the box body, and to carry it in and out in sequence. The object of the present invention is to provide a welding object jig loading/unloading device for a welding robot, which aims to improve the robot operating rate by shortening the welding work stop period of the welding robot.

This will be explained in detail with reference to the embodiments shown in the figures. For convenience of explanation, the left and right in FIGS. 1 and 2 will be referred to as "left" and "right", and the left and right in FIG. 3 will be referred to as "front" and "rear".

Reference numeral 1 denotes the main body of the welding robot, which includes a vertical frame 3 erected on a rear extension base 2' of a planar convex base 2, and a vertical frame 3 extending forward left from the side surface of the vertical frame 3 in the vertical direction (arrow Z direction). ), a horizontal arm frame 4 that can be moved in the direction of the arrow; The welding point of the torch 6, that is, the tip of the welding wire 6a, is always placed on the vertical axis L, no matter what attitude the torch 6 is in.

Reference numeral 7 denotes a welding object attachment tool placed in the front position of the base 2, which includes a horizontally long first frame 8 fixedly installed on the base 2, and a horizontally long first frame 8 placed on the first frame 8 in the left-right direction (arrow X
a second frame 9 that can move in the direction), a third frame 10 that is placed on the second frame 9 and that can move in the front-rear direction (arrow Y direction), and a front part of the third frame 10. It consists of a mounting plate 11, etc., which is pivotally supported at the front and back and can be rotated around the central axis M in the front-rear direction (in the direction of the arrow Θ).

Reference numeral 12 denotes a jig fixing clamp device provided on the mounting plate 11, and has the following configuration. That is, in FIGS. 3 and 5, reference numerals 12a and 12b denote a pair of mutually parallel rotating shafts supported by appropriate bearings 12c at the flat left and right end portions of the mounting plate 11.
At the top of a and 12b, 1 is bent to face each other.
One end of each of the pair of clamp claws 12d, 12e is fixed, and rectangular clamp plates 12f, 12g are fixed inside the other end of each of the clamp claws 12d, 12e. Further, the bases of push levers 12h, 12i are fixed to the lower portions of the rotating shafts 12a, 12b, and the tips of the push levers 12h, 12i are connected to the cylindrical body base 12J ₁ of the air cylinder 12j below the back surface of the mounting plate 11. The air cylinder 12j is suspended in the air by pivotally connecting the _ends of the rod 12J and the rod 12J.
_2J2 , the clamp claws 12d, 1
2e are rotated in opposite directions.

Reference numeral 13 denotes a jig loading/unloading device disposed on the base 2 between the main body 1 and the workpiece fixture 7, and has the following configuration. Reference numeral 14 denotes a fixed frame body that is long in the left-right direction, and a pair of rails 15, 15 are laid on the upper surface 14a, spaced apart from each other in the front and rear directions, and spanning the entire length in the left-right direction. Reference numerals 16 and 16' denote left and right carts on which box bodies 17 and 17' are mounted, respectively, and a set of four flanged rollers 18 and 18', which are pivotally supported on the left and right, front and rear sides, respectively, roll on the rail 15. It can be freely engaged.

Reference numerals 19 and 19' denote pressed members that are vertically disposed at the rear center portion and the front center portion of the lower surfaces of the left and right bogies 16 and 16′, respectively, and are pushed by the upper surface 14, respectively.
They are loosely inserted into left and right elongated openings 14a ₁ and 14a ₂ cut by a predetermined length on the rear left and front right sides of a, and their tips reach the internal space 14b of the fixed frame 14. 20, 20' are the internal spaces 14b.
Two air cylinders installed front and rear in opposite left and right directions are used to connect the tips of the rods 20a and 20'a extending leftward and rightward to the pushed member 1.
9, 19', and the rod 20
Due to the extension movements of a and 20'a, the left and
The right bogies 16, 16' are made to run separately in the left and right directions along the rail 15.

21a ₁ , 21a ₂ , 21b ₁ , 21b ₂ are the left and right ends of the opening 14a ₁ and the right and right ends of the opening 14a ₂ , respectively.
A positioning buffer stopper made of a soft material such as rubber is fixed on the left end, among which stoppers 21a ₁ and 21b ₁
The left and right carts 16, 16' are placed in the left and right standby positions (arrows A, A') by contact with the pushed members 19, 19', respectively, and the stoppers 21a ₂ , 21b ₂ are moved, respectively. the pressed member 19;
19', the left and right carts 16, 16' are placed at the left and right jig loading/unloading positions (arrows B, B') defined at the left center and right center. be.

Reference numeral 22 denotes a jig that is removably placed on each of the boxes 17 and 17', and as shown in FIG. and the front end and upper end are connected to the rear surface of the vertical plate 22a and the horizontal plate 22b, respectively.
It consists of a pair of left and right leg plates 22c and 22d fixed to the lower surface, and the workpiece W to be welded is fixed onto the horizontal plate 22b using an appropriate fixture (not shown). 22a ₁ and 22a ₂ are holes for positioning the mounting plate 11 drilled in the left and right parts of the vertical plate 22a;
22C ₁ , 22C ₂ , 22d ₁ , 22d ₂ are a pair of front and rear notches cut into the lower ends of the left and right leg plates 22c and 22d, respectively, and 22c ₃ and 22d ₃ are the lower portions of the left and right leg plates 22c and 22d. Guide rollers 22c ₄ and 22d ₄ are pivotally supported on the central outer surface of the left and right leg plates 2.
Box bodies 17, 1 bored at the front lower ends of 2c and 22d
7' is a positioning hole.

Reference numeral 23 denotes a jig transfer mechanism provided in each of the box bodies 17, 17', which has the following configuration.

That is, to explain the jig transfer mechanism 23 provided in the box body 17 based on FIGS. 3 and 4, 24a and 24b
25a ₁ , 25a 2 , 25b _{1 ,} 2 are fixed shafts spaced apart from each other in the upper part of the box body 17 in the left-right direction;
Reference numerals 5b ₂ denote a pair of left and right front and rear bending levers whose intermediate bending portions are pivotally connected to the fixed shafts 24a and 24b, respectively, and the ends of one side of the front bending levers 25a ₁ and 25a ₂ are connected to the rear bending lever 25b _{1 .} , 25b ₂ (equal length to the front bending levers 25a ₁ , 25a ₂ ) and the links 26a, 25b 2 having the same length, respectively.
26b, and furthermore, the ends of the one side of the rear bending levers 25b ₁ and 25b ₂ are connected to each other by a connecting rod 27.

Further, each of the bending levers 25a ₁ , 25a ₂ , 25
A roller 28 is installed at the tip of the other side of b ₁ and 25b ₂ , respectively.
a ₁ , 28a ₂ , 28b ₁ , and 28b ₂ are pivotally supported.

Reference numeral 29 denotes an air cylinder installed in the box body 17 so as to be able to swing vertically.
The bending levers 25a ₁ , 2
5a ₂ , 25b ₁ , 25b ₂ are openings 17a ₁ , 17a ₂ , 17b ₁ , 17 cut into the upper surface of the box body 17, respectively.
b ₂ is made to swing up and down so that it appears and disappears.

Guide members 30a and 30b are fixedly installed on the upper surface of the left and right center portions of the box body 17, and curved guide grooves 30a ₁ and 30b ₁ with upper and lower openings are cut in the guide members 30a and 30b. When carrying out and transferring to the box body 17, the guide rollers 22c ₃ and 22d ₃ are engaged with and guided by the curved guide grooves 30a ₁ and 30b ₁ , respectively.

Reference numerals 31a and 31b are positioning protrusions drilled on the front left and upper right surfaces of the box body 17, and these are fitted into the holes 22c ₄ and 22d ₄ , respectively, when carrying out and transferring the jig 2.
2 on the box body 17.

Reference numerals 32a and 32b are positioning protrusions protruding from the left and right sides of the lower surface of the mounting plate 11, and the base is thick and the tip is _thin . ₂ to position the jig 22 on the mounting plate 11.

Reference numerals 33a and 33b are jig separation auxiliary claws whose bases are fixed to the intermediate portions of the rotating shafts 12a and 12b, which swing in synchronization with the unclamping operation of the jig 22 by the jig fixing clamp device 12, and bend the tip. Notches 11a whose ends are cut at the left and right ends of the mounting plate 11,
Jig 2 from the protruding position on the surface of the mounting plate 11 from 11b
The second vertical plate 22a is pushed to smoothly separate the jig.

Reference numerals 34a and 34b are manual switches provided on the left and right sides of the fixed frame 14, respectively.
Before attaching the unwelded workpiece W to the jigs 22, 22 on the jigs 17' and removing the welded workpiece W', the worker switches the switch 34a,
34b to the OFF side, left and right trolleys 16,1
A signal prohibiting movement of the workpiece 6' is issued so that the work of removing and attaching the objects to be welded W' and W can be completely performed.

35 is a control device with a built-in microcomputer installed separately from the main body 1, the workpiece attachment 7, and the jig loading/unloading device 13, and controls the vertical movement of the arm frame 4, the torch attachment 5, and the torch 6. Oscillation, feeding control of welding wire 6a, feeding/cutting control of welding current and shielding gas, first and second frames 9,
10, rotation control of the mounting plate 11, movement of the left and right carts 16, 16' by air cylinders 20, 20', jig fixing clamp device 12 and jig transfer mechanism 23 by air cylinders 12j, 29, respectively.
and the air cylinders 20, 20' based on the signal information from the manual switches 34a, 34b.
This system comprehensively controls the entire automatic welding equipment, including starting and stopping operations.

Next, the effect will be explained.

Now, the workpiece attachment tool 7 fixes and holds the jig 22 carried in from the box 17' of the right truck 16' on the mounting plate 11, and works with the main body 1 to fix the workpiece to the jig 22. Assume that automatic welding is being performed on object W. During this welding work, the right truck 16' and the box body 17' are stopped at the right standby position A' in an empty state.

Further, it is assumed that the left truck 16 is stopped at the left side standby position A, and the jig 22 is placed on the box 17 at a predetermined position. That is, the guide roller 22
c ₃ and 22d ₃ are guide members 30a and 30b, respectively.
The guide grooves 30a ₁ and 30b ₁ are engaged with the bottoms of the guide grooves 30a 1 and 30b 1, and the protrusions 31a and 31b are respectively aligned with the positioning holes 22.
c ₄ and 22d ₄ are fitted. Further, the jig transfer mechanism 23 of the box body 17 has the air cylinder 29 in the rod shortened state, and the bending levers 25a ₁ , 25a ₂ , 2
5b ₁ , 25b ₂ , etc. are evacuated into the box body 17.

In the above situation, the worker turned on the manual switch 34a.
is operated to the OFF side to send a signal prohibiting movement of the left truck 16 to the control device 35, and then the unwelded workpiece W is placed on the box body 16 and fixed in a predetermined position with an appropriate fixture. Next, turn the manual switch 34a
By operating it to the ON side, a signal for permission to move the left truck 16 is sent to the control device 35.

When the robot completes the welding work, the main body 1 raises the arm frame 4 to appropriately retract the torch 6 upward. The mounting plate 11 has two protrusions 32a, 3
2b, and the third frame 10 moves to the most retracted position, and the second frame 9 moves to the right and reaches the jig loading/unloading position B on the right side. Stop at a position facing ′. Next, the air cylinder 20' performs a shortening operation of the rod 20'a, causing the right truck 16' to traverse to the left and stop at the jig loading/unloading position B' on the right side.

Next, by the cooperation of the jig transfer mechanism 23 of the box body 17' and the jig fixing clamp device 12, the jig 22 loaded with the welded workpiece W' is carried out and transferred from the mounting plate 11 to the box body 17'. do. In carrying out this work, first, by extending the rod 19a of the air cylinder 29, the bending lever 25a1, _etc. is swung by 90 degrees, and the tip rollers _28a1 , _28b1 , _28a2 , _28b2 are moved to the left and right leg plates of the jig 22, respectively. It is placed directly below 22c and 22d. Next, the rod _12j2 of the air cylinder 12j is shortened, causing the clamping claws 12d and 12e to open outward to release the clamping action of the jig 22, and in synchronization with this, the jig separation auxiliary claws 33a and 33b also swing. Then, the tips of the auxiliary claws collide with the front surface of the vertical plate 22a of the jig 22, pushing the jig 22 backward. At this time, the positioning holes 22a ₁ and 22a ₂ are connected to the projections 32a,
Just before it separates from the tip of 32b, the entire jig 22 falls slightly and creates notches 22c ₁ , 22c ₂ , 22d ₁ , 22
d ₂ are respectively the rollers 28a ₁ , 28b ₁ , 28
a ₂ and 28b ₂ , and the jig 22 is held horizontally.

Next, by the shortening operation of the rod 29a of the air cylinder 29, the jig 22 is lowered diagonally backward while remaining in a horizontal state, and is placed on the box body 17'. At the final stage of this downward movement, the guide rollers 22c ₃ and 22d ₃
are engaged with and guided by the guide grooves 30a ₁ and 30b ₁ , so that the holes 22c ₄ and 22d ₄ and the protrusions 31a and 31b are reliably fitted.

When the above-mentioned unloading/transferring operation is completed, the second frame 9 etc. move to the left and stop at a position facing the jig loading/unloading position B on the left side, and the right truck 16 is moved by the rod extension operation of the air cylinder 20'. '・Box 17'・Jig 2
2 and the welded workpiece W' integrally move to the right and stop at a standby position A' on the right side. Thereafter, the worker operates the manual switch 34b to the OFF side, removes the welded workpiece W' from the jig 22, and attaches a new unwelded workpiece W to the jig 22.

Furthermore, the right truck 16' etc. are placed in the waiting position on the right side.
After reaching A', rod 2 of air cylinder 20
Due to the 0a shortening operation, the left truck 16, box body 17, jig 22, and workpiece W are moved to the jig loading/unloading position B on the left side.
(solid line in Figures 1, 2, and 3).

Then, by cooperation of the jig transfer mechanism 23 of the box body 17 and the jig fixing clamp device 12, the jig 22 carrying the unwelded workpiece W is transferred from the box body 17 to the mounting plate 11. This loading/unloading operation is performed in the exact opposite order to the aforementioned loading/unloading operation.

That is, the bending levers 25a ₁ , 25a ₂ , 25b ₁ , 2 are moved by the extension action of the rod 29a of the air cylinder 29
5b ₂ synchronously swings 90 degrees in the counterclockwise direction (Fig. 3), and at this time the rollers 28a ₁ , 28a ₂ , 28b ₁ ,
28b ₂ has notches 22c ₁ , 22d ₁ , 22 respectively
c ₂ and 22d ₂ to lift the jig 22 diagonally forward and upward while keeping it horizontal. At the final point of lifting this jig 22, the two protrusions 32a of the mounting plate 11,
The tips of 32b fit into the holes 22a ₁ and 22a ₂ , respectively (double-dashed line in FIG. 3).

Next, the clamp claws 12d and _12e close inward due to the shortening action of the rod 12j2 of the air cylinder 12j, and at this time, the clamp plates 12f and 12g close to the vertical plate 2.
The vertical plate 22a is brought into close contact with the mounting plate 11 by pressing the entire jig 22 forward while coming into contact with the rear surface of the vertical plate 22a. In the final stage of this clamping operation, the bases of the protrusions 32a and 32b are connected to the holes 22a ₁ and 22.
a _{2 , the} entire jig 22 rises slightly above the height position _indicated by the two _- dot chain line in FIG _{. 2} , 28b ₁ , and 28b ₂ upward.

When the jig clamping operation described above is completed, the bending levers 25a ₁ , 25a ₂ , 25b ₁ , and 25b ₂ return to their original positions as indicated by solid lines in FIG. 3 due to the shortening operation of the rod 29a of the air cylinder 29. Finally, the rod 20a of the air cylinder 20 is extended, causing the left truck 16 and the box 17 to move to the left and stop at the standby position A on the left side.

In this state, the torch 6 is moved in the directions of arrows Z and ψ according to a predetermined process sequence programmed in advance, and the mounting plate 11, jig 22, and workpiece W are integrally moved in the directions of arrows X, Y, and Θ. Automatic welding work is performed while controlling the relative position of the torch 6 and the object W to be welded by moving the torch 6 in the appropriate direction.

As detailed above, when using the device of the present invention,
A pair of left and right trolleys for loading and unloading jigs, which can run separately, are placed near the welding object attachment device, and the workpieces to be welded can be attached to and removed from the mounting plate on the welding robot side by alternating one round trip of both carts. By moving the jig to the specified loading/unloading position, the jig is sequentially moved through the cooperation of the jig fixing clamp device installed on the mounting plate and the jig transfer mechanism built into the box on the trolley. The welding robot is able to perform a series of operations automatically, and the troublesome work of attaching and detaching the workpiece to and from the jig can be done during the welding process on the box of the other side cart in the standby position. This makes it possible to shorten the downtime and greatly improve the robot operating rate.

[Brief explanation of the drawing]

The drawings all show one embodiment of the present invention; Fig. 1 is a front view, Fig. 2 is a plan view, Fig. 3 is an enlarged side view taken in the direction of Fig. 2, and Fig. 4 is a jig. 3 is a plan view taken in the direction indicated by the arrow .about. in FIG. 3, FIG. In the figure, 1 is the main body of the welding robot, 6 is the torch,
7 is a welding object attachment device, 11 is a mounting plate, 12 is a jig fixing clamp device, 13 is a jig loading/unloading device, 1
6, 16' are left and right carts, 17, 17' are box bodies, 2
2 is a jig, 23 is a jig transfer mechanism, W and W' are unwelded and welded objects, respectively, and 35 is a control device.

Claims (1)

[Claims] 1. A main body equipped with a torch movable in the vertical direction, and a welding object fixture equipped with a mounting plate movable in the left-right and front-back directions, which can be attached to the torch by an appropriate control device. In a welding robot that automatically welds by controlling the relative position of the two plates by moving one or both of the plates, each of two standby positions defined on the left and right outside the movable range of the mounting plate and the movable range. A pair of left and right carts provided so as to be able to traverse in the left and right direction between the jig loading and unloading positions defined in the box, and a box body mounted on each of the carts with the jig placed on the top surface; A pair of left and right units built into the box body and pivoting upward from the top surface of the box body so as to lift the jig at the jig loading/unloading position and bring the vertical plates of the jig into contact with the surface of the mounting plate in an overlapping manner. A jig transfer mechanism equipped with front and rear bending levers, and a vertical plate of the jig that swings toward the front of the mounting plate from the left and right sides of the mounting plate and clamps the vertical plate of the jig between the mounting plate and the mounting plate. 1. A jig loading/unloading device for a workpiece to be welded in a welding robot, comprising a jig fixing clamp device equipped with a pair of clamp claws for fixing the jig by pressure. 2. The jig fixing clamp device includes a pair of rotating shafts that are vertically supported in parallel on the left and right sides of the mounting plate, and a pair of rotating shafts that are bent to face each other and can be retracted from the front surface of the mounting plate. a pair of clamp claws with clamp plates fixed to a shaft; a pair of push levers having bases fixed to each of the rotating shafts; and air pivotally connected between the tips of the push levers behind the mounting plate. A jig loading/unloading device for a workpiece to be welded in a welding robot according to claim 1, comprising a cylinder. 3 A jig separation auxiliary claw is fixed to the rotating shaft, and when the clamp claw swings in the direction of releasing the fixation of the jig, the tip of the auxiliary claw protrudes to the front surface of the mounting plate and causes the jig to move outward. A jig loading/unloading device for a workpiece to be welded in a welding robot according to claim 2, which is adapted to be pushed. 4. The jig includes the vertical plate that can be superimposed on the mounting plate, a horizontal plate that has one end fixed to an intermediate part of the vertical plate and on which a workpiece to be welded can be placed and fixed, and the horizontal plate. Left and right 1 that can be installed vertically on the lower surface of the box and placed on the box body
A jig loading/unloading device for a workpiece to be welded in a welding robot according to claim 1, comprising a pair of leg plates. 5. Claim 4, wherein the jig is positioned with respect to the mounting plate by fitting two protrusions protruding from the mounting plate into two holes drilled in the vertical plate. A device for carrying in and out jigs for workpieces in welding robots. 6 A patent in which the jig is positioned relative to the box by fitting two protrusions protruding from the upper surface of the box into holes drilled in each of the lower surfaces of the pair of leg plates. A jig loading/unloading device for a workpiece to be welded in a welding robot according to claim 4. 7. The jig transfer mechanism includes a pair of front and rear fixed shafts that are pivoted in the left-right direction in the upper part of the box interior, and a pair of left and right front and rear fixed shafts that have intermediate bending parts pivoted to each of the fixed shafts.
a rear bending lever, a link that pivotally connects the tip of the front bending lever on one side and a middle part of the side of the rear bending lever, and a connecting rod that connects the tips of the left and right rear bending levers on the one side. , and an air cylinder having a rod tip pivotally connected to the connecting rod, and the tip of the other side of the front/rear bending lever protrudes upward from the box body and is placed on the box body by the operation of the air cylinder. A device for carrying in and out a jig for a workpiece in a welding robot according to claim 1, wherein the jig can be lifted diagonally upward toward the mounting plate.