JP5473060B2 - Welding robot - Google Patents

Description

  The present invention relates to a welding robot for performing welding by feeding a welding wire by a wire feeder.

  Today, in order to improve the work efficiency of welding, it is widely performed to automate welding using a welding robot. This welding robot has a welding torch attached to the tip of the wrist of the manipulator, and the welding wire wound around the wire reel is fed to the welding torch by a wire feeder attached to the top of the manipulator. Is done. The manipulator is provided with first to sixth axes, and the tip position and posture of the welding torch can be changed by turning, swinging, or rotating each axis. (For example, refer to Patent Document 1).

  Conventionally, a welding wire wound around a wire reel is guided from a wire reel to a wire feeder by a conduit cable, and proceeds from the wire feeder to the center of a one-wire power cable to be supplied to a welding torch. . This one-wire power cable is provided with a coil liner for guiding a welding wire at the center, and a hose for flowing gas on the outer periphery thereof. And the outer periphery of this hose is covered with a conductive wire for supplying electric power, and the outermost periphery is covered with insulation. Thus, since the one-wire power cable has a multiple structure, it has a high bending rigidity and is difficult to bend.

  Conventionally, a single-wire power cable has high bending rigidity and is difficult to bend, and in order to enable deformation, the single-wire power cable has been positioned in the outer space of the upper arm from the wire feeder to the welding torch. However, if the one-wire power cable is arranged outside, the one-wire power cable may interfere with the workpiece or surrounding devices. Therefore, as shown in FIG. 7, the one-wire power cable is placed in the inner space of the upper arm. There has been proposed a welding robot having a configuration of being inserted and arranged. FIG. 7 is a diagram showing a conventional welding robot.

  In FIG. 7, a turning base 12 is attached to the tip of the base 11 of the welding robot 9, and the turning base 12 turns around the first axis 11a (A arrow direction). A lower arm 13 is attached to the tip of the turning base 12, and the lower arm 13 swings around the second shaft 12a (in the direction of arrow B). An upper arm support 23 is attached to the tip of the lower arm 13, and the upper arm support 23 swings around the third shaft 13a (in the direction of arrow C). An upper arm 24 is attached to the tip of the upper arm support 23, and the upper arm 24 rotates about the fourth axis (rotation axis) 16 of the upper arm support 23 (direction of arrow D).

  An oscillating body 17 is attached to the tip of the upper arm 24, and the oscillating body 17 oscillates around a fifth axis 18 (in the direction of arrow E) orthogonal to the fourth axis 16. A rotating body 60 is attached to the tip of the rocking body 17, and the rotating body 60 rotates around a sixth axis 20 orthogonal to the fifth axis (oscillating axis) 18. A welding torch 19 is attached to the rotating body 60. The first shaft 11a to the sixth shaft 20 are provided with a motor via a speed reducer, and are driven by inputting a command from a robot control device (not shown).

  A wire feeder 25 is attached to the upper arm support 23 shown in FIG. 7, one end of the one-wire power cable 50 is connected to the wire feeder 25, and the other end is inserted through the upper arm support 23 and the upper arm 24. It passes through the hole, extends in the longitudinal direction of the upper arm 24, and is connected to the welding torch 19. The upper arm 24 has its tip end side offset from the fourth shaft 16 to the side, and the oscillating body 17 supports the rotating body 60 in a cantilevered manner. For this reason, the one-wire power cable 50 can run along the longitudinal direction of the upper arm 24 in the upper arm 24 and in the adjacent space.

JP 2003-94168 A

  In the above-described conventional welding robot 9, the one-wire power cable 50 passes through the insertion holes of the upper arm support 23 and the upper arm 24, extends in the longitudinal direction of the upper arm 24, and is connected to the welding torch 19. . Therefore, when the manipulator is operated, it is possible to reduce the interference of the one-wire power cable 50 with the upper arm 24, the work piece or the jig, so that the manipulator can be operated freely and is optimal. The position of the welding torch 19 can be taken. However, depending on the operation of the upper arm 24, the one-wire power cable 50 is subjected to external forces such as bending, twisting, and pulling, and the burden on the one-wire power cable 50 is large.

  In particular, as shown in FIG. 8, when the one-wire power cable 50 is built in the upper arm 24, the one-wire power cable 50 is oscillated via the oscillating body 17 provided in the upper arm 24 and at the tip of the upper arm 24. It is connected to a welding torch (not shown) provided on the moving body 17. In such a state, as shown in the figure, the one-wire power cable 50 is drawn in an S shape, so that the welding wire inserted into the one-wire power cable 50 has an excessive feeding resistance. The feeding property of the receiving and welding wire is deteriorated, which causes welding failure. FIG. 8 is a diagram illustrating an arrangement state of a one-line power cable of a welding robot according to the prior art.

  An object of the present invention is to provide a welding robot that can improve the durability of a one-wire power cable and the feedability of a welding wire.

The first invention is
A base provided with a first axis reduction gear;
A turning base attached to the tip of the base and turning around the first axis;
A lower arm attached to the tip of the swivel base and swinging about the second axis;
An upper arm support attached to the tip of the lower arm and swinging about the third axis;
An upper arm attached to the tip of the upper arm support and rotating about the fourth axis;
An oscillating body that is supported by the tip of the upper arm in a cantilever or both-end manner and oscillates about the fifth axis;
A rotating body attached to the tip of the rocking body and rotating about the sixth axis;
A welding torch attached to the rotating body;
A wire feeder for feeding a welding wire to the welding torch;
A conduit cable having one end connected to the wire reel and the other end connected to the wire feeder;
In a welding robot provided with a one-wire power cable having one end connected to the wire feeder and the other end connected to a welding torch,
The upper arm support is cantilevered at the tip of the lower arm,
The wire feeder is rotatably attached to the base arm or the lower arm, which is a position below the support, with respect to the upper arm support ,
The first wire power cable extends from the shaft portion toward the distal end side of the upper arm so as not to pass through the shaft portion of the upper arm, and intersects the rotation axis from below to above. Arranged to have a portion and a second portion intersecting from above to below,
The upper arm has a member that does not project a portion between the first portion and the second portion from the upper arm,
A hollow portion is formed in the first shaft reducer,
The other end of the conduit cable is inserted from the base end portion of the base, is inserted through the hollow portion of the first shaft reducer and the turning base, and is connected to the wire feeder. It is a welding robot.

The second invention is
The lower arm according to the first invention is a first lower arm,
The second lower arm shaft speed reducer attached to the tip of the first lower arm and formed with a hollow portion is attached to the second lower arm that rotates around the second lower arm axis,
The other end of the conduit cable is inserted from the base end of the base, and is inserted through the hollow portion of the first shaft reducer, the turning base, and the hollow portion of the second lower arm shaft reducer. A welding robot characterized by being connected to a feeder.

  The welding robot of the present invention does not cause local bending in the one-wire power cable between the wire feeder and the welding torch, and can stably feed the welding wire to the welding torch. Since the burden on the one-wire power cable can be reduced, the durability of the one-wire power cable can be improved. In addition, since the conduit cable is inserted from the base end of the base, even if the welding robot is turned around the first axis of the base, the conduit cable may interfere with peripheral devices and jigs. Absent.

It is a side view of the robot for welding of Embodiment 1 of this invention. It is a front view of the robot for welding of Embodiment 1 of the present invention. It is a top view of the robot for welding of Embodiment 1 of this invention. It is a figure explaining operation | movement of the welding robot of Embodiment 1 of this invention. It is sectional drawing of the upper arm of the welding robot of Embodiment 1 of this invention. It is a figure which shows the robot for welding of Embodiment 2 of this invention. It is a figure which shows the robot for welding of a prior art. It is a figure which shows the arrangement | positioning state of the single wire type power cable of the welding robot of a prior art.

[Embodiment 1]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the invention will be described based on examples with reference to the drawings. FIG. 1 is a side view of the welding robot according to the first embodiment of the present invention, FIG. 2 is a front view of the welding robot according to the first embodiment of the present invention, and FIG. It is a top view of the robot for welding of the form 1 of. 1 to 3, the same functions as those of the prior art welding robot shown in FIG. 7 are denoted by the same reference numerals, description thereof is omitted, and other functions will be described. As shown in FIG. 2, the lower arm 13 of the welding robot 10 has a configuration in which the middle in the vertical direction is bent so that the upper side is offset outward from the lower side. As shown in FIGS. 2 and 3, a shaft portion 14 a is provided at the base end portion of the upper arm 14, and the shaft portion 14 a is rotatably inserted into the support portion 15 a of the upper arm support 15. The shaft portion 14 a is rotationally driven by a motor N provided on the upper arm support 15.

  The wire feeder 30 is arranged to be offset from the rotation axis 16 (longitudinal axis) (downward in FIG. 1) by being rotatably attached to the lower arm 13. A connecting portion 14b is provided between the shaft portion 14a of the upper arm 14 and the tip portion thereof. The connecting portion 14b is disposed offset from the rotation axis 16 in a direction (upward in FIG. 3) perpendicular to the offset direction of the wire feeder 30 with respect to the rotation axis 16. An eaves portion 14c that is disposed offset from the rotation axis 16 is formed in a portion far from the lower arm 13 on the shaft portion 14a side of the connecting portion 14b. The upper portion of the one-line power cable 50 is covered with the eaves portion 14c. Further, the remaining portion of the connecting portion 14b where the eaves portion 14c is not provided is a portion where the curved part of the one-wire power cable 50 is located upward from the connecting portion 14b, that is, farther from the lower arm 13 than the eaves portion 14c. It is possible to make it.

  As shown in FIG. 3, the connecting portion 14b is offset laterally (upward in FIG. 3) from the rotation axis 16, and a swing shaft 18 as a fifth shaft is provided at the tip thereof, and the swing body is moved by the upper arm. 17 is cantilevered, and the rocking body 17 is supported by the rocking shaft 18 so as to be tiltable or rockable (in the direction of arrow E in FIG. 1).

  An upper arm support 15 is cantilevered at the tip of the lower arm 13. On the side of the upper arm 14 of the wire feeder 30, a wire delivery port 42 as a wire exit is provided. The one-wire power cable 50 is extended toward the distal end side of the upper arm 14 from the shaft portion 14a so that the portion extending from the wire delivery port 42 does not pass through the shaft portion 14a of the upper arm 14, and the rotation axis line 16 is arranged so as to be close to or intersecting with each other, and a space from below the eaves portion 14c of the upper arm 14 to the vicinity of the swing shaft 18 (fifth axis) is drawn along a rotation axis 16 while drawing a smooth curve. Has been. When the oscillating body 17 rotates around the oscillating shaft 18 orthogonal to the rotational axis 16, the wire feeder 30 rotates in accordance with the follow-up operation of the one-wire power cable 50.

  Instead of being attached to the lower arm 13, the wire feeder 30 may be attached to the upper arm support 15 so as to be rotatable at a position closer to the base end side than the support portion 15a. The wire feeder 30 in FIG. 1 is shown by a solid line when attached to the lower arm 13, and is shown by a dotted line when attached to a position closer to the base end side of the upper arm support 15. Also, the wire feeder 30 in FIG. 2 is shown only when attached to a position closer to the base end side of the upper arm support 15. A hollow portion is formed in the first shaft speed reducer provided on the base 11, one end of the conduit cable 39 is connected to the wire reel 40, and the other end is inserted from the base end portion of the base 11. A hollow portion of the shaft reducer and the turning base 12 are inserted and connected to the wire feeder 30, and a welding wire supplied from the wire reel 40 is guided.

  The wire delivery port 42 is located below the rotation axis 16 of the upper arm 14 and is disposed so that the center axis 42 a intersects the rotation axis 16 of the upper arm 14. That is, the wire delivery port 42 is located below the rotation axis 16 of the upper arm 14 and is disposed so as to face obliquely upward with respect to the rotation axis 16. The reason why the wire delivery port 42 intersects the rotation axis 16 from below to above in this way is that when the one-wire power cable 50 connected to the wire delivery port 42 runs along the longitudinal direction of the upper arm 14, the welding wire goes straight. This is because, in an easy state, the S-shape that has conventionally occurred in the one-wire power cable 50 connected to the wire feeder 30 is eliminated. As a result, the bending radius of the one-wire power cable 50 can be increased.

  The operation will be described below with reference to FIG. FIG. 4 is a diagram for explaining the operation of the welding robot according to the first embodiment of the present invention. In the same figure, for the case where the lower arm 13 of FIG. 1 is standing upright along the vertical direction, the lower arm 13 is tilted backward (rotated to the opposite side to the welding torch 19 side) around the second shaft 12a. The state of the robot 10 is shown.

  From this state, even if the elevation angle of the oscillator 17 is increased or decreased, the upper arm is supported so that the wire delivery port 42 is positioned below the rotation axis 16 and obliquely upward with respect to the rotation axis 16. A wire feeder 30 is installed on the body 15. The single-wire power cable 50 connected to the wire delivery port 42 is disposed so as not to pass through the shaft portion 14a in the support portion 15a and to intersect the rotation axis 16.

  As shown in FIG. 1, the upper arm 14 is connected between the shaft portion 14 a and the tip portion by a single connecting portion 14 b, and the connecting portion 14 b is in the offset direction of the wire feeder 30 with respect to the rotation axis 16 ( It is arranged offset with respect to the rotation axis 16 in a direction orthogonal to (downward in FIG. 3) (upward in FIG. 3). And the rocking body 17 is cantilevered by the upper arm 14, and a part of the site | part extended from the wire delivery port 42 of the one-line-type power cable 50 is arrange | positioned along the connection part 14b. Further, the single-wire power cable 50 is extended toward the distal end side of the upper arm 14 from the shaft portion 14 a so as not to pass through the shaft portion 14 a of the upper arm 14, and is arranged so as to intersect the rotation axis 16. Yes.

  As a result, unlike the conventional arrangement state of the one-wire power cable 50 shown in FIG. 8, the one-wire power cable 50 does not have an S shape, and the feeding resistance of the welding wire can be suppressed. Further, when the upper arm 14 is swung up and down (in the direction of arrow C) around the third shaft 13a from the state of FIG. 1, or when the elevation angle of the rocking body 17 is changed, the posture change of the one-line power cable 50 is changed. Even if there exists, since the wire feeder 30 is rotatably attached to all directions, the wire feeder 30 rotates following the attitude | position of the one-wire-type power cable 50. FIG. As a result, local bending does not occur in the one-wire power cable 50 between the wire feeder 30 and the welding torch 19, and the welding wire can always be stably fed to the welding torch 19. Further, when the upper arm 14 rotates around the rotation axis 16, the one-wire power cable 50 is not entangled with the upper arm 14, or the rotation range of the upper arm 14 for preventing the tangling of the one-wire power cable 50 is limited. Can be relaxed.

  Further, unlike the prior art, the wire feeder 30 is not positioned on the extension line of the upper arm 14, so that the arrangement space of the wire feeder 30 on the back surface portion of the welding robot, that is, the welding torch of the upper arm 14 is particularly good. An arrangement space for the wire feeder 30 on the side opposite to the side on which 19 is located is not necessary. For this reason, the interference area | region of the back part of a welding robot can be reduced by the part which this arrangement | positioning space was abbreviate | omitted. The interference area is a space that interferes with peripheral devices or jigs of the robot due to the posture change of the welding robot. Further, since the conduit cable 39 is inserted from the base end portion of the base 11, even if the welding robot is turned around the first axis of the base 11, the conduit cable 39 is connected to peripheral devices, jigs, and the like. There is no interference.

  Further, since the wire feeder 30 is attached to the upper arm support 15 so as to be rotatable around an axis perpendicular to the rotation axis 16, the one-wire power cable 50 follows the movement of the oscillator 17. Even if it operates, the wire feeder 30 rotates in accordance with the following operation of the one-wire power cable 50. As a result, local bending of the one-wire power cable 50 due to the movement of the oscillator 17 can be prevented, and the welding wire can be stably fed to the welding torch 19.

  Furthermore, since the single wire power cable 50 is not passed through the shaft portion 14 a of the upper arm 14, it is not necessary to form a through hole through which the single wire power cable 50 passes through the shaft portion 14 a of the upper arm 14. As a result, since the configuration of the shaft portion 14a of the upper arm 14 can be simplified and the number of parts can be reduced, the cost of the welding robot main body can be reduced.

  Further, since the conduit cable 39 is inserted from the base 11 of the welding robot 10, the operation of the welding robot is not limited by the conduit cable as in the prior art, so a wide operating range of the welding robot is ensured. be able to.

  Furthermore, since the burden on the one-wire power cable 50 can be reduced, the durability of the one-wire power cable 50 can be improved, and the feedability of the welding wire is not reduced. Can be improved.

  As shown in FIG. 5, in the upper arm 14, a cylindrical portion 14d is provided between the shaft portion 14a and the tip portion, and the one-wire power cable 50 is inserted into the cylindrical portion 14d. May be. FIG. 5 is a cross-sectional view of the upper arm of the welding robot according to the first embodiment of the present invention. In the same figure, in the cylindrical portion 14d, an inlet hole 14e for inserting the one-line power cable 50 is provided at a position closer to the shaft portion 14a, that is, at a position on the tip side than the shaft portion 14a, and an opening 14f is provided at the tip portion. The opening 14f is used as an outlet hole, or an outlet hole is provided near the tip of the cylindrical portion 14d, so that the one-wire power cable 50 is arranged so as to exit from the cylindrical portion 14d.

  Further, a bifurcated portion having a tip portion may be branched and extended on the shaft portion 14 a of the solid body of the upper arm 14. In this case, the bifurcated portions are separated from each other in a direction orthogonal to the offset direction (downward direction in FIG. 1) of the wire feeder 30 with respect to the rotation axis 16, and the rotation axis 16 is arranged with the rotation axis 16 in between. It is arranged offset with respect to. And the rocking | swiveling body 17 is both supported by the front-end | tip part of both bifurcated parts. In this case, it arrange | positions so that a part of site | part extended from the wire delivery port 42 of the one-wire-type power cable 50 may enter between two forks.

  Further, the one-wire power cable 50 is not necessarily arranged so as to intersect the rotation axis 16, and the portion of the one-wire power cable 50 connected to the wire delivery port 42 rotates with respect to the upper arm support 15. In order not to pass through the base end portion of the freely supported upper arm 14, the base arm portion may extend toward the distal end side of the upper arm 14 from the base end portion and may be disposed so as to approach the rotation axis 16.

  Further, the upper arm 14 has an opening on the offset direction side (downward side in FIG. 1) of the wire feeder 30 with respect to the rotation axis 16 and includes a groove section having a concave cross section in the rotation axis direction. 16 may be arrange | positioned and it may arrange | position so that a part of 1 line type power cable 50 extended from the wire delivery port 42 may enter.

[Embodiment 2]
FIG. 6 is a diagram showing a welding robot according to a second embodiment of the present invention, and shows a case of a welding robot provided with seven axes. In this figure, the function different from the six-axis welding robot of the first embodiment of the present invention shown in FIG. 1 is that the lower arm 13 of the welding robot 10 is different from the first lower arm 31 and the second lower arm of the welding robot 8. 32, the second lower arm 32 is attached to the tip of the first lower arm 31 and rotates around the second lower arm shaft 32a.

  A hollow portion is formed in the second lower arm shaft speed reducer provided in the second lower arm 32. One end of the conduit cable 39 is connected to a wire reel 40 (not shown), and the other end is inserted from the base end portion of the base 11, and the hollow portion of the first shaft speed reducer, the swivel base 12, and the second lower arm shaft speed reducer. It is connected to the wire feeder 30 through the hollow part of the machine. In other respects, the same functions as those of the welding robot according to the first embodiment of the present invention shown in FIG. The operation and effect are also the same as those of the welding robot according to the first embodiment of the present invention shown in FIG.

8 welding robot 9 welding robot 10 welding robot 11 base 11a first shaft 12 turning base 12a second shaft 13 lower arm 13a third shaft 14 upper arm 14a shaft portion 14b connecting portion 14c eaves portion 14d tube portion 14e inlet hole 14f Opening 15 Upper arm support 15a Support 16 Rotating axis 17 Oscillating body 18 Oscillating shaft 19 Welding torch 20 6th shaft 23 Upper arm support 24 Upper arm 25 Wire feeder 30 Wire feeder 31 First lower arm 32 Second lower arm 32a 2nd lower arm axis | shaft 39 Conduit cable 40 Wire reel 42 Wire delivery port 42a Center axis 50 Single wire type power cable 60 Rotating body N Motor

Claims (2)

A base provided with a first axis reduction gear;
A turning base attached to the tip of the base and turning around the first axis;
A lower arm attached to the tip of the swivel base and swinging about the second axis;
An upper arm support attached to the tip of the lower arm and swinging about the third axis;
An upper arm attached to the tip of the upper arm support and rotating about the fourth axis;
An oscillating body that is supported by the tip of the upper arm in a cantilever or both-end manner and oscillates about the fifth axis;
A rotating body attached to the tip of the rocking body and rotating about the sixth axis;
A welding torch attached to the rotating body;
A wire feeder for feeding a welding wire to the welding torch;
A conduit cable having one end connected to the wire reel and the other end connected to the wire feeder;
In a welding robot provided with a one-wire power cable having one end connected to the wire feeder and the other end connected to a welding torch,
The upper arm support is cantilevered at the tip of the lower arm,
The wire feeder is rotatably attached to the base arm or the lower arm, which is a position below the support, with respect to the upper arm support ,
The first wire power cable extends from the shaft portion toward the distal end side of the upper arm so as not to pass through the shaft portion of the upper arm, and intersects the rotation axis from below to above. Arranged to have a portion and a second portion intersecting from above to below,
The upper arm has a member that does not project a portion between the first portion and the second portion from the upper arm,
A hollow portion is formed in the first shaft reducer,
The other end of the conduit cable is inserted from the base end portion of the base, is inserted through the hollow portion of the first shaft reducer and the turning base, and is connected to the wire feeder. Welding robot. The lower arm according to claim 1 and a first lower arm;
The second lower arm shaft speed reducer attached to the tip of the first lower arm and formed with a hollow portion is attached to the second lower arm that rotates around the second lower arm axis,
The other end of the conduit cable is inserted from the base end of the base, and is inserted through the hollow portion of the first shaft reducer, the turning base, and the hollow portion of the second lower arm shaft reducer. A welding robot characterized by being connected to a feeder.

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