CN111051017A

CN111051017A - Workpiece conveying device

Info

Publication number: CN111051017A
Application number: CN201880058123.7A
Authority: CN
Inventors: 真木大树; 若杉谕; 堀尾明里; 山中和幸
Original assignee: CKD Corp
Current assignee: CKD Corp
Priority date: 2017-09-12
Filing date: 2018-09-10
Publication date: 2020-04-21
Anticipated expiration: 2038-09-10
Also published as: JP6949634B2; CN111051017B; TW201919834A; JP2019048364A; WO2019054323A1; TWI693132B

Abstract

A workpiece conveying device (10) is provided with a robot (11) including a robot arm (19), and a balancer (30) arranged in parallel with the robot (11). The balancer (30) is provided with a balancer base, a horizontal articulated parallel link type balancer arm (35), a workpiece mounting mechanism (46) supported by the upper end of the balancer arm (35), and a coupling member (52) coupled to the workpiece mounting mechanism (46). The front end of the robot arm (19) is coupled to the coupling member (52) so that the front end of the robot arm (19) is coupled to the upper end of the balancer arm (35), and the balancer arm (35) is located below the robot arm (19).

Description

Workpiece conveying device

Technical Field

The present invention relates to a workpiece transfer apparatus having a robot arm and a balancer provided in parallel with the robot.

Background

As a workpiece conveying apparatus, for example, a conveying apparatus disclosed in reference 1 is known. As shown in fig. 8, the load carrying device 80 disclosed in reference 1 includes a balancer arm 81 fixed to a floor and a robot 91 that grips and moves a workpiece W. The robot 91 includes a connection mechanism 92 at the front end. The balancer arm 81 includes a connected mechanism 82 and a hand device 83 at the tip. The balancer arm 81 includes a cylinder 84 for driving the balancer arm 81 and a control unit, not shown, for controlling the driving of the cylinder 84. The pressure of the air cylinder 84 is adjusted by the control unit in accordance with the load of the workpiece W held by the hand device 83.

The connecting mechanism 92 of the robot 91 is coupled to the connected mechanism 82 of the balancer arm 81. When the robot 91 operates, the hand device 83 at the tip of the balancer arm 81 moves following the link mechanism 92, and the workpiece W is conveyed. The workpiece W is supported by the robot 91 with almost no weight by the assistance or assistance of the balancer arm 81.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2009-262304

Disclosure of Invention

Problems to be solved by the invention

In the configuration including the balancer arm 81 for assisting the conveyance of the workpiece W, the load conveyance device 80 disclosed in patent document 1 is desired to be downsized in the height direction.

The invention aims to provide a workpiece conveying device which can be miniaturized in the height direction.

Means for solving the problems

The workpiece transfer apparatus includes a robot including a robot arm having a base end supported by a robot base, and a balancer provided in parallel with the robot. The balancer includes a balancer base, a parallel link type balancer arm, a workpiece mounting mechanism, and a coupling member, the balancer base is disposed side by side with the robot base, the balancer arm has a base end portion supported by the balancer base, is of a horizontal articulated type movable in a horizontal direction, and is movable in a vertical direction, the workpiece mounting mechanism is supported by an upper end portion of the balancer arm, and the coupling member is coupled to the workpiece mounting mechanism. The front end of the robot arm is coupled to the coupling member, so that the front end of the robot arm is coupled to the upper end of the balancer arm, which is located below the robot arm.

Drawings

Fig. 1 is a side view of a workpiece conveying apparatus according to an embodiment.

Fig. 2 is a side view showing a state in which the balancer arm is located at the lowest position in the workpiece conveying device of fig. 1.

Fig. 3 is a plan view of the workpiece transfer device of fig. 1.

Fig. 4 is a side view showing a state in which the balancer arm is located at the highest position in the workpiece conveying device of fig. 1.

Fig. 5A is a schematic diagram showing a joint driving device constituting the balancer arm of fig. 4.

Fig. 5B is a view schematically showing a state in which the joint drive device of fig. 5A is displaced.

Fig. 6 is a rear view of a workpiece mounting mechanism provided in the workpiece conveying device shown in fig. 1.

Fig. 7 is a side view of the workpiece mounting mechanism of fig. 6.

Fig. 8 is a diagram showing a conventional workpiece conveying apparatus.

Detailed Description

An embodiment of an embodied workpiece conveying apparatus will be described below with reference to fig. 1 to 7.

As shown in fig. 1, the workpiece conveying apparatus 10 includes a robot 11 and a balancer 30. The robot 11 includes a columnar robot base 12 fixed to the floor F. In the workpiece conveying apparatus 10, the direction in which the balancer 30 is disposed is set to the front with respect to the robot base 12 of the robot 11. Therefore, the robot base 12 of the robot 11 is disposed behind the balancer 30. As shown in fig. 3, when the balancer 30 is viewed from the robot base 12 in a plan view of the workpiece conveying device 10 from above, the left side of the robot base 12 is set as the left side, and the right side of the robot base 12 is set as the right side.

As shown in fig. 1, 2, or 3, the robot 11 is of an articulated type. A plate-shaped base (base)13 is supported on the upper surface 12a of the robot base 12. An arm support portion 16 is supported by the base portion 13. The arm support portion 16 is rotatable with respect to the base portion 13 about an axis line L1 extending in the vertical direction as a rotation center. The 1 st end in the longitudinal direction of the 1 st arm member 15 is supported by the arm support portion 16 so as to be rotatable about the 1 st arm shaft 14. The axis of the 1 st arm shaft 14 extends in the horizontal direction.

The longitudinal direction 1 st end of the 2 nd arm member 18 is supported by the longitudinal direction 2 nd end of the 1 st arm member 15 so as to be rotatable about the 2 nd arm shaft 17 as a rotation center. The axis of the 2 nd arm shaft 17 extends in the horizontal direction. The axis of the 1 st arm shaft 14 is parallel to the axis of the 2 nd arm shaft 17.

The coupling mechanism 21 is supported at the 2 nd end in the longitudinal direction of the 2 nd arm member 18 so as to be rotatable about the coupling shaft 20 as a rotation center. The 2 nd arm member 18 includes a 1 st member 18a coupled to the 1 st arm member 15 via a 2 nd arm shaft 17 and a 2 nd member 18b coupled to the coupling mechanism 21 via a coupling shaft 20. The 1 st member 18a and the 2 nd member 18b are coupled to each other by a rotation shaft 18 c. The 2 nd member 18b is rotatable with respect to the 1 st member 18a with the rotation shaft 18c as a rotation center.

The axis of the connecting shaft 20 extends in the horizontal direction. The axis of the 1 st arm shaft 14, the axis of the 2 nd arm shaft 17, and the axis of the connecting shaft 20 are parallel to each other. Further, the base 13, the arm support portion 16, the 1 st arm shaft 14, the 1 st arm member 15, the 2 nd arm shaft 17, the 2 nd arm member 18, the coupling shaft 20, and the coupling mechanism 21 constitute a robot arm 19. The base 13 of the base end of the robot arm 19 is supported by the robot base 12. The distal end of the robot arm 19 is constituted by a coupling mechanism 21.

The robot arm 19 can rotate (can move) in the horizontal direction with the axis L1 as the rotation center. Further, the robot arm 19 can adjust the position of the coupling mechanism 21 in the vertical direction and the distance of the coupling mechanism 21 from the robot base 12 by adjusting the rotation amount of the 1 st arm member 15 having the 1 st arm shaft 14 as the rotation center and the rotation amount of the 2 nd arm member 18 having the 2 nd arm shaft 17 as the rotation center.

The balancer 30 includes a balancer base 31, a horizontal articulated or parallel link type balancer arm 35 supported on an upper surface 31a of the balancer base 31, and a workpiece mounting mechanism 46 connected to an upper end of the balancer arm 35. The balancer base 31 is fixed to the floor F. The balancer base 31 is fixed to the front of the robot base 12 at a position close to the robot base 12. The upper surface 31a of the balancer base 31 is located below the upper surface 12a of the robot base 12. In other words, the upper surface 12a of the robot base 12 is located at a higher position than the upper surface 31a of the balancer base 31.

The balancer arm 35 is configured by connecting a plurality of joints. The balancer arm 35 includes a plurality of (2 in the present embodiment) joint driving devices. That is, the balancer arm 35 includes the 1 st joint drive device 32A and the 2 nd joint drive device 32B, the base end portion of the 1 st joint drive device 32A is supported by the balancer base 31, and the 2 nd joint drive device 32B is supported by the tip end portion of the 1 st joint drive device 32A. When the robot 11 moves the workpiece W toward the working point, the 1 st and 2 nd

joint driving devices

32A and 32B are driven in accordance with the height and position of the workpiece W, respectively, in order to balance the weight.

As shown in fig. 1 or 5A, the

joint driving devices

32A and 32B include a pair of 1 st frame 33 and a pair of 2 nd frame 34, respectively. Each of the

joint driving devices

32A and 32B includes an arm member 45. The 1 st end in the longitudinal direction of each arm member 45 is rotatably supported by the corresponding 1 st frame 33 via the corresponding 1 st rotating shaft 33 a. The longitudinal direction 2 nd end of each arm member 45 is rotatably supported by the corresponding 2 nd frame 34 via the corresponding 2 nd rotating shaft 34 a. The 1 st frame 33 and the 2 nd frame 34 are coupled to each other by arm members 45. The 1 st and 2 nd end portions of the 1 st joint drive device 32A and the 1 st and 2 nd end portions of the 2 nd joint drive device 32B function as rotatable joints.

As shown in fig. 5A, the

joint driving devices

32A and 32B are each provided with an actuator 60 therein. Each actuator 60 moves the corresponding 2 nd frame 34 by swinging the corresponding arm member 45. The actuator 60 is a fluid pressure cylinder (in the present embodiment, an air cylinder). The actuator 60 includes a cylinder 61(cylinder tube) attached to the arm member 45 and a piston rod 62 (cylinder rod) that moves in the axial direction of the cylinder 61. A piston 66 movable in the axial direction of the cylinder 61 is housed in the cylinder 61, and the piston 66 is connected to the 1 st end in the longitudinal direction of the piston rod 62. The piston 66 defines a pressure chamber 61a inside the cylinder 61.

A pneumatic device 61c is connected to the pressure chamber 61a via a pipe 61 b. The controller 61d is connected to the pneumatic device 61 c. Air controlled by the controller 61d is supplied from the pneumatic device 61c to the pressure chamber 61a through the pipe 61 b. The piston 66 is moved by the pressure (fluid pressure) of the compressed air supplied to the pressure chamber 61a, and the position at which the piston rod 62 protrudes from the cylinder 61 is displaced.

The actuator 60 includes a guide member 65 coupled to a projecting end (longitudinal direction 2 nd end) of the piston rod 62 projecting from the cylinder 61. The guide member 65 includes a roller 65a, and the protruding end of the piston rod 62 is connected to the guide member 65 so as to be rotatable about the rotation center of the roller 65a by a rotation shaft 65 c.

The 1 st end in the longitudinal direction of the connecting member 64 is supported by the rotating shaft 65c of the guide member 65, and the 2 nd end in the longitudinal direction of the connecting member 64 is rotatably supported by the 1 st frame 33 via the rotating shaft 68. The connecting member 64 extends obliquely with respect to the piston rod 62.

As shown in fig. 1 or 5A, each of the

joint driving devices

32A and 32B includes a parallel arm 70. Each parallel arm 70 extends parallel to the corresponding arm member 45. The longitudinal 1 st end of each parallel arm 70 is rotatably supported by the rotating shaft 68 of the corresponding 1 st frame 33. The longitudinal direction 2 nd end of each parallel arm 70 is rotatably supported by the rotating shaft 69 of the corresponding 2 nd frame 34. The 1 st frame 33 and the 2 nd frame 34 are coupled to each other by parallel arms 70.

In each of the

joint driving devices

32A and 32B, the 2 nd frame 34 is rotatable about the corresponding 1 st frame 33 in a plan view. The 1 st frame 33, the 2 nd frame 34, the arm member 45, and the parallel arm 70 constitute a parallel link.

As shown in fig. 5B, when the arm member 45 and the parallel arm 70 are swung (displaced) relative to the 1 st frame 33 by the parallel link, the 2 nd frame 34 can be moved parallel to the 1 st frame 33. That is, the 2 nd frame 34 can be displaced in the up-down direction with respect to the 1 st frame 33.

In order to balance the weight of the workpiece W at the position where the balancer arm 35 moves, the controller 61d calculates the pressure of the compressed air to be supplied to the pressure chambers 61a of the 1 st and 2 nd

joint driving devices

32A and 32B, and drives the air pressure device 61c based on the calculated result to supply the compressed air to the pressure chambers 61 a.

As shown in fig. 1 or 2, the 1 st frame 33 of the 1 st joint drive device 32A is supported by the balancer base 31 so as to be rotatable about the 1 st vertical axis 29 extending in the vertical direction as a rotation center. The 1 st joint drive device 32A can rotate in the horizontal direction with the 1 st vertical axis 29 as the rotation center.

The 2 nd frame 34 of the 1 st joint drive device 32A and the 1 st frame 33 of the 2 nd joint drive device 32B are connected by a rotary joint 44. The rotary joint 44 rotatably holds the

joint driving devices

32A and 32B. The

joint driving devices

32A and 32B rotate relative to the rotary joint 44 about the 2 nd vertical axis 44a as a rotation center. The 2 nd vertical axis 44a is perpendicular to a connection surface that connects the 1 st joint drive device 32A and the 2 nd joint drive device 32B to each other. That is, the 1 st joint drive device 32A and the 2 nd joint drive device 32B are coupled to each other so as to be relatively rotatable about the 2 nd vertical axis 44 a. Therefore, the balancer arm 35 can be horizontally displaced (movable) to the left and right with the 1 st vertical axis 29 and the 2 nd vertical axis 44a as the rotation center.

The workpiece mounting mechanism 46 is supported by the upper end of the balancer arm 35, that is, the upper end of the 2 nd frame 34 of the 2 nd joint drive device 32B. The workpiece mounting mechanism 46 includes a load support portion 48 that supports the load of the workpiece W. The load support portion 48 is supported by the upper end of the 2 nd frame 34 of the 2 nd joint drive device 32B. The load support portion 48 is supported by the 2 nd frame 34 so as to be rotatable about a vertical axis 47 extending in the vertical direction.

A plate-shaped workpiece support 49 is connected to a front surface of one side surface of the load support 48, and the workpiece W is supported by the workpiece support 49. The workpiece support portion 49 protrudes from the load support portion 48 in a direction away from the robot arm 19 in the horizontal direction. The load of the workpiece W supported by the workpiece support portion 49 is supported by the load support portion 48.

As shown in fig. 6 or 7, a plate-shaped support portion 50 is provided to protrude from one side surface of the load support portion 48, that is, the upper surface of the surface perpendicular to the surface to which the workpiece support portion 49 is connected. A rod-shaped gripping member 51 is fixed to the support portion 50 so as not to be rotatable. The center axis M of the gripping member 51 extends in the horizontal direction. The center portion of the gripping member 51 in the extending direction along the center axis M is fixed to the support portion 50.

The workpiece mounting mechanism 46 includes a coupling member 52 coupled to the gripping member 51. The connecting member 52 includes a bifurcated leg portion 55 and a plate-like connecting piece 57 projecting upward from the upper surface of the leg portion 55. The 2 leg portions 55 have facing surfaces facing each other. The connecting member 52 has an insertion groove 54 formed between the facing surfaces of the 2 leg portions 55. The support portion 50 is inserted into the insertion groove 54. The connecting member 52 includes a connecting hole 52a extending horizontally through 2 leg portions 55. The holding member 51 is inserted into the 2 coupling holes 52 a. The holding member 51 is engaged with the inner surfaces of the 2 coupling holes 52a, whereby the coupling member 52 is coupled to the holding member 51. The holding member 51 is held by an operator for the operation of the balancer 30.

The support portion 50 is interposed between 2 leg portions 55 of the coupling member 52. Both ends in the axial direction of the gripping member 51 fixed to the support portion 50 protrude from the side surfaces of the 2 leg portions 55 of the coupling member 52. The coupling member 52 is slidable in the extending direction of the central axis M of the holding member 51.

As shown in fig. 1, the coupling mechanism 21 of the robot arm 19 is coupled to the coupling piece 57 of the coupling member 52 coupled to the workpiece mounting mechanism 46. The coupling piece 57 protrudes upward from the load support portion 48. With such a configuration, the distal end of the robot arm 19 is coupled to the upper end of the balancer arm 35. Therefore, the upper end of the balancer arm 35 is located below the front end of the robot arm 19. That is, the balancer arm 35 is located below the robot arm 19. The connecting piece 57 and the connecting mechanism 21 are connected to each other so as to be rotatable relative to each other about a connecting axis 57a extending in the horizontal direction.

As shown in fig. 7, in a side view of the workpiece conveying apparatus 10, the center axis M of the gripping member 51 does not overlap the vertical axis 47, and the gripping member 51 is located at a distance from the vertical axis 47. Specifically, the center axis M of the gripping member 51 is located farther from the balancer base 31 than the vertical axis 47 in the horizontal direction.

As shown in fig. 2, in the balancer arm 35 having the above-described configuration, the upper surfaces of the arm members 45 of the 1 st joint drive device 32A and the 2 nd joint drive device 32B are horizontal, and the lowest position posture S1 of the balancer arm 35 is set to a posture in which the workpiece mounting mechanism 46 is at the lowest position. In the lowest position posture S1, the upper surface of the arm member 45 in the 2 nd joint drive device 32B is located at the same height as the upper surface 12a of the robot base 12 in the robot 11.

As shown in fig. 4, in the workpiece conveying apparatus 10, the posture in which the 2 nd frame 34 of each of the 1 st joint drive device 32A and the 2 nd joint drive device 32B is at the highest position is set as the highest position posture S2 of the balancer arm 35. The workpiece transport apparatus 10 moves the balancer arm 35 between the lowest position posture S1 and the highest position posture S2 to follow the movement of the robot arm 19.

In the workpiece conveying apparatus 10, when only the robot arm 19 is viewed, the movable range of the robot arm 19 in the height direction is located above and below the upper surface 12a of the robot base 12. However, since the tip of the robot arm 19 is coupled to the upper end of the balancer arm 35, the movable range of the robot arm 19 is limited to a range that matches the movable range of the balancer arm 35.

The movable range of the balancer arm 35 is from the lowest position posture S1 to the highest position posture S2 of the balancer arm 35. Here, it can be seen that if the height of the balancer arm 35 in the lowest position posture S1 is higher than the upper surface 12a of the robot base 12, the range in which the movable ranges of the robot arm 19 and the balancer arm 35 overlap becomes smaller. Therefore, by setting the upper surface of the 2 nd joint drive device 32B of the balancer arm 35 in the lowest position posture S1 to be at the same height as the upper surface 12a of the robot base 12, the range in which the movable range of the robot arm 19 and the movable range of the balancer arm 35 overlap is maximized.

In the workpiece conveying apparatus 10 configured as described above, the coupling mechanism 21 serving as the distal end portion of the robot arm 19 is coupled to the coupling member 52 of the workpiece mounting mechanism 46, so that the distal end portion of the robot arm 19 is coupled to the upper end portion of the balancer arm 35. Further, even when in any of the postures including the lowest position posture S1 and the highest position posture S2, the balancer arm 35 is always positioned below the robot arm 19. Therefore, the height dimension of the workpiece conveying device 10 in the vertical direction is determined by the robot arm 19.

In the workpiece conveying apparatus 10, when the robot arm 19 is rotated in the horizontal direction, the balancer arm 35 is also rotated in the horizontal direction following the robot arm 19. When the tip of the robot arm 19 is displaced in the vertical direction, the upper end of the balancer arm 35 is also displaced so as to follow the robot arm 19. Therefore, the balancer arm 35 is not located above the robot arm 19 but displaced below the robot arm 19.

In the workpiece conveying apparatus 10, when the robot 11 conveys the workpiece W, the balancer arm 35 is displaced according to the weight and height of the workpiece W, and the pressure of the compressed air supplied from the air pressure machine 61c to each pressure chamber 61a is adjusted by the controller 61 d. As a result, the conveyance of the workpiece W by the robot 11 can be assisted by the balancer arm 35, and the workpiece W is supported by the robot arm 19 with almost no weight by the assistance (assistance) of the balancer arm 35.

The operation of the work conveying apparatus 10 configured as described above will be described below. When the robot 11 is driven, the workpiece support 49 moves toward the workpiece W set at a predetermined position, and the workpiece support 49 supports the workpiece W. Subsequently, the robot 11 moves the workpiece W to the conveyance position. At this time, the workpiece W is supported by the balancer arm 35 with almost no weight.

According to the above embodiment, the following effects can be obtained.

(1) In the workpiece conveying apparatus 10, the upper end portion of the balancer arm 35 and the front end portion of the robot arm 19 are connected by the workpiece mounting mechanism 46. The balancer arm 35 is displaced in the horizontal direction in accordance with the rotation of the robot arm 19 in the horizontal direction, and is displaced in the vertical direction in accordance with the displacement of the robot arm 19 in the vertical direction. Further, the balancer arm 35 is always displaced below the robot arm 19. Therefore, the height dimension of the workpiece transport apparatus 10 depends on the height dimension of the robot 11, and compared to a workpiece transport apparatus in which a balancer is disposed above the robot arm, the workpiece transport apparatus 10 can be downsized in the height direction by eliminating the balancer arm 35 above the robot arm 19.

(2) In the lowermost position posture S1 of the balancer arm 35, the upper surface of the 2 nd joint drive device 32B is located on the same plane as the upper surface 12a of the robot base 12. Therefore, the robot arm 19 supported on the upper surface 12a of the robot base 12 is always positioned above the balancer arm 35 in the lowest position posture S1. Therefore, the balancer arm 35 is not positioned above the robot arm 19, and the workpiece conveying apparatus 10 can be downsized in the height direction.

(3) The distal end of the robot arm 19 and the upper end of the balancer arm 35 are coupled to each other by coupling the gripping member 51 and the coupling member 52. The holding member 51 is inserted through a coupling hole 52a that penetrates the coupling member 52 in the horizontal direction. Therefore, when an inertial force in the horizontal direction is generated during conveyance of the conveyed workpiece W, the displacement of the balancer arm 35 along the center axis M of the gripping member 51 can be allowed, and the stress generated in the balancer arm 35 can be reduced.

(4) In a side view of the workpiece conveying apparatus 10, the center axis M of the gripping member 51 is located farther from the balancer base 31 in the horizontal direction than the vertical axis 47 of the rotation axis of the workpiece mounting mechanism 46. Therefore, the force of the balancer arm 35 rotating by the inertial force acting on the conveyed workpiece W is not easily transmitted to the shaft member having the vertical axis 47. As a result, the resistance to the inertial force of the balancer arm 35 can be improved, and the positioning accuracy of the workpiece W can be improved.

(5) The upper surface 12a of the robot base 12 is set at a position higher than the upper surface 31a of the balancer base 31. Therefore, compared to a case where the upper surface 31a of the balancer base 31 is set to a position higher than the upper surface 12a of the robot base 12, for example, the range in which the movable range of the robot arm 19 and the movable range of the balancer arm 35 overlap can be enlarged. In the present embodiment, the upper surface 31a of the balancer base 31 is lowered so that the upper surface 12a of the robot base 12 is flush with the upper surface of the 2 nd joint drive device 32B when the balancer arm 35 is in the lowest position posture S1, whereby the range in which the movable ranges of the robot arm 19 and the balancer arm 35 overlap can be maximized.

However, the above embodiment can be modified as follows.

In the workpiece conveying apparatus 10, the balancer base 31 of the balancer 30 may be provided side by side on the robot 11, for example, on the left or right in fig. 3. At this time, by disposing the parts (the rotary joints 44) to which the 1 st and 2 nd

joint driving devices

32A and 32B are connected on the side where the balancer 30 is disposed, the workpiece transfer apparatus 10 can be used without interference between the robot arm 19 and the balancer arm 35.

Further, in the plan view of the workpiece conveying device 10, by setting the condition that the longitudinal direction axes of the 1 st joint driving device 32A and the 2 nd joint driving device 32B do not coincide with each other, the direction in which the 1 st and 2 nd

joint driving devices

32A and 32B are folded inward can be fixed, and the working area of the workpiece conveying device 10 can be effectively used.

The number of joint driving devices connected to the balancer arm 35 can be changed according to the length of the robot arm 19.

The balancer arm 35 can also be configured such that the longitudinal dimension of the joint driving device is different from that of the embodiment. For example, the longitudinal direction dimensions of the 1 st joint drive device 32A and the 2 nd joint drive device 32B may be different, or the longitudinal direction dimensions of both the 1 st joint drive device 32A and the 2 nd joint drive device 32B may be longer or shorter than those of the embodiment.

The form of the robot arm 19 can be changed as long as the upper end of the balancer arm 35 can be connected to the tip of the robot arm 19.

At the upper end of the balancer arm 35, the center axis M of the gripping member 51 may be located not far from the vertical axis 47 of the rotation axis of the workpiece mounting mechanism 46 but at a position intersecting the vertical axis 47.

When the balancer arm 35 is in the lowest position posture S1, the upper surface 12a of the robot base 12 can also be at a different height from the upper surface of the 2 nd joint drive device 32B.

In the connection between the upper end of the balancer arm 35 and the distal end of the robot arm 19, the connection member 52 may be connected to a side surface (for example, the rear surface, the left surface, or the right surface) other than the side surface to which the workpiece support 49 is connected, instead of the connection member 52 being connected to the upper surface of the load support 48.

In the 1 st joint driving device 32A and the 2 nd joint driving device 32B, the actuator 60 may be a hydraulic cylinder instead of an air cylinder.

In the balancer arm 35, the 1 st joint driving device 32A of the joint driving devices coupled to the balancer base 31 can be changed to a rotary member that rotates only in the horizontal direction.

Claims

1. A workpiece conveying device is provided with a robot and a balancer,

the robot includes a robot arm having a base end portion supported by a robot base,

the balancer is arranged side by side with the robot,

the balancer has a balancer base, a parallel link type balancer arm, a work mounting mechanism, and a connecting member,

the balancer base and the robot base are arranged side by side,

the balancer arm has a base end supported by the balancer base, is of a horizontal articulated type movable in a horizontal direction, and is movable in a vertical direction,

the workpiece mounting mechanism is supported by an upper end portion of the balancer arm,

the connecting member is connected to the work mounting mechanism,

the front end of the robot arm is coupled to the coupling member so that the front end of the robot arm is coupled to the upper end of the balancer arm,

the balancer arm is located below the robot arm.

2. The workpiece handling apparatus of claim 1,

the balancer arm has a plurality of joint driving devices rotatably coupled to each other, and is disposed so that the farther from the balancer base, the higher the joint driving devices are,

each of the joint driving devices includes an arm member constituting a parallel link and a parallel arm disposed below the arm member in parallel to the arm member,

when the arm members of the plurality of joint driving devices are horizontal, the balancer arm assumes a lowermost position posture so that the workpiece mounting mechanism is located at a lowermost position,

the upper surface of the robot base is at the same height as the upper surface of the arm member positioned highest in the balancer arm in the lowest position posture.

3. The workpiece handling apparatus according to claim 1 or 2,

the workpiece carrying mechanism is provided with a rod-shaped holding member extending in the horizontal direction,

the connecting member includes a connecting hole penetrating the connecting member in a horizontal direction, and the connecting member is connected to the workpiece mounting mechanism by inserting the holding member into the connecting hole.

4. The workpiece handling apparatus of claim 3,

the balancer arm is supported by the balancer base so as to be rotatable in a horizontal direction, the robot arm is supported by the robot base so as to be rotatable in the horizontal direction, the workpiece mounting mechanism is supported by an upper end portion of the balancer arm so as to be rotatable about a vertical axis as a rotation center, and a center axis of the grip member is located farther from the balancer base than the vertical axis in the horizontal direction.

5. The workpiece conveying apparatus according to any one of claims 1 to 4,

a connecting mechanism for forming the front end of the robot arm,

the coupling mechanism and the coupling member are coupled to each other so as to be relatively rotatable about a coupling axis extending in a horizontal direction.