JP2017196679A - Electric gripper device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light and compact electric gripper device of which controller cables can be easily installed and controlled, although the device has multiple hands.SOLUTION: The electric gripper device comprises: a housing 21; first sliders 36 each having a first claw; second sliders 37 each of which has a second claw, and forms a hand in cooperation with the first slider 36; and a driver 22 for driving the first and second sliders 36, 37 in the respective directions opposite to each other. The driver 22 includes: a drive shaft (a ball screw shaft 53); a motor 61; and a transmission mechanism for the sliders, which converts rotation of the drive shaft into translation in a direction where a workpiece is gripped or released, and then transmits the translation to the first and second sliders 36, 37. The hands are provided at multiple positions each of which is adjacent to the drive shaft, as viewed in an axial direction of the drive shaft. The transmission mechanism for the sliders has transmission members (a first movement member 51, a second movement member, and pins 43), for transmitting motive power from the drive shaft to all of the respective first and second sliders 36, 37 of the hands.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an electric gripper device having a pair of claws for gripping a workpiece.

  Conventionally, for example, when a workpiece is gripped by an articulated robot, a hand having a pair of claws that sandwich the workpiece is used. When gripping a workpiece having a different size or shape, the hand is exchanged for one corresponding to the workpiece. Hand exchange is often performed using a tool exchange mechanism called a so-called tool changer. When exchanging the hand, it is necessary to stop the power source connected to the hand, change the parameters of the hand, return to the origin, and the like, and the work time required for the exchanging work is long.

In order to eliminate the waste of work time associated with such hand replacement, for example, as described in Patent Document 1 and Patent Document 2, it is conceivable to equip and use a plurality of types of hands.
Patent Document 1 discloses a robot hand having three hands. Each of these hands includes a pair of claws that sandwich the workpiece and an air cylinder for driving these claws, and can be individually operated.

Patent Document 2 discloses an electric gripper device having two hands. Each of these hands is constituted by an electric gripper.
By adopting the configurations described in Patent Document 1 and Patent Document 2, it is possible to select and use a hand that is suitable for a workpiece without performing a hand replacement operation.

JP 2014-140910 A JP 2009-184027 A

  Each of the plurality of hands disclosed in Patent Literature 1 and Patent Literature 2 has an individual drive source. For this reason, when the configurations described in Patent Document 1 and Patent Document 2 are adopted, actuators, control cables, and the like are required as many as the number of hands. The first problem is that the mass of the robot tip increases. The second problem is that the installation work of the control cable and the control of the hand become complicated.

  The present invention was made to solve such problems, and despite being equipped with a plurality of hands, it is lightweight and compact, and can be easily installed with a control cable and controlled by a single controller. It is an object of the present invention to provide an electric gripper device that can be easily performed.

  In order to achieve this object, an electric gripper device according to the present invention has a housing attached to a tool mounting seat of a robot and a first claw for gripping the workpiece with the work held between the outer surface of the housing. A first slider supported so as to be capable of reciprocating in a workpiece gripping / releasing direction, and a second claw for sandwiching the workpiece in cooperation with the first claw, the outer surface of the housing, A second slider which is supported at a position adjacent to the first slider so as to be reciprocally movable in the workpiece gripping / releasing direction, and which forms a hand in cooperation with the first slider; and the first and second sliders A driving device that drives the sliders in opposite directions, the driving device rotatably supporting the housing, a motor that drives the driving shaft, and rotation of the driving shaft. Convert to parallel movement in the workpiece gripping / release direction The slider has a transmission mechanism for transmitting to the first slider and the second slider, and the hand is provided at a plurality of positions adjacent to the drive shaft as viewed from the axial direction of the drive shaft. The transmission mechanism includes a transmission member that transmits power from the drive shaft to all the first and second sliders.

  According to the present invention, in the electric gripper device, the drive shaft is constituted by a ball screw shaft, and the ball screw shaft has a first screw portion and a second screw portion in which the screw directions are opposite to each other. The transmission mechanism includes a first ball screw nut screwed into the first screw portion, a second ball screw nut screwed into the second screw portion, and the first ball screw nut. And a first movement member as the transmission member connecting all the first sliders, and a second movement as the transmission member connecting the second ball screw nut and all the second sliders. You may have a member.

  In the electric gripper device according to the present invention, the drive device has a transmission mechanism for a ball screw shaft that connects the motor and the drive shaft, and the motor is attached to the tool mounting seat in the housing. You may arrange | position between an attaching part and the said ball screw axis | shaft.

  In the electric gripper device according to the present invention, the casing is formed in a rectangular parallelepiped shape having four side surfaces extending in the workpiece gripping / releasing direction, and the mounting portion attached to the tool mounting seat in the casing is The first and second sliders are provided on one side of the housing having one of the four side surfaces, and the first and second sliders correspond to the other three side surfaces of the four side surfaces. Each may be provided in each part.

  According to the present invention, in the electric gripper device, a plurality of spiral cam grooves are formed concentrically, and a side portion of the housing located on one end side in the workpiece gripping / release direction is arranged in a workpiece gripping / release direction. And a cam follower that is rotatably inserted in the cam groove, and is supported by the casing so as to be movable toward and away from the axis of the cam member. You may provide the several claw member made and the transmission mechanism for cam members which transmits motive power from the said drive device to the said cam member.

  In the electric gripper device according to the present invention, the drive shaft includes a drive-side bevel gear, and the transmission mechanism includes a plurality of driven-side bevel gears that mesh with the drive-side bevel gear, and a plurality of spiral cams. A groove is formed concentrically, a plurality of cam members provided for each driven bevel gear, the driven bevel gear is provided at one end, and the cam member is provided at the other end. A plurality of driven shafts rotatably supported by the casing so that a member is positioned in the vicinity of each hand, and a first slider provided on the first slider and movably inserted in the cam groove. You may have a cam follower and the 2nd cam follower provided in the said 2nd slider and inserted in the said cam groove so that movement was possible.

  According to the present invention, in the electric gripper device, a cam member provided in a state of rotating integrally with a distal end portion of the drive shaft and having a plurality of spiral cam grooves formed concentrically, and moved to the cam groove A plurality of claw members having a cam follower that is freely inserted and supported so as to be movable toward and away from the axis of the cam member may be provided on the housing.

  In the present invention, hands composed of the first slider and the second slider are provided at a plurality of positions of the housing. For this reason, the hand suitable for a workpiece | work can be selected by changing the position of a housing | casing with a robot. The claws of these hands move in the workpiece gripping / releasing direction as the drive shaft rotates. For this reason, it becomes possible to drive a plurality of hands with one drive device.

  This electric gripper device is lighter in weight because it requires only one drive device and control cable including the controller, compared to a conventional device having an actuator for each hand, and its installation space is narrow. It is compact because it is good. Further, the installation work of the drive device and the control cable can be easily performed, and the control of the drive device can be easily performed.

  Therefore, according to the present invention, it is possible to provide an electric gripper device that is light and compact, and can easily install and control a control cable, despite being equipped with a plurality of hands. it can. The tip of the robot hand equipped with this electric gripper device is small and light.

1 is a perspective view of an articulated robot equipped with an electric gripper device according to a first embodiment. It is a perspective view of an electric gripper device. It is a perspective view of an electric gripper device. It is sectional drawing seen from the right direction of the electric gripper apparatus. It is sectional drawing seen from the workpiece gripping / release direction of the electric gripper device. The fracture position in FIG. 5 is a position indicated by the line VV in FIG. It is a perspective view which shows the principal part of an electric gripper apparatus. It is a disassembled perspective view which shows the structure of a housing | casing. It is a perspective view of the electric gripper device by a 2nd embodiment. It is a perspective view which shows the principal part of the electric gripper apparatus by 2nd Embodiment. It is a top view of a cam member. It is sectional drawing of the transmission gripper apparatus by 3rd Embodiment. It is a front view of the 1st hand. It is the XIII-XIII sectional view taken on the line in FIG. It is a front view of the 2nd and 3rd hand. It is the XV-XV sectional view taken on the line in FIG.

(First embodiment)
Hereinafter, an embodiment of an electric gripper device according to the present invention will be described in detail with reference to FIGS.
As shown in FIGS. 1 to 3, the electric gripper device 1 shown in FIG. 1 constitutes a robot hand of the articulated robot 2 and includes first to third hands 3 to 5. The electric gripper device 1 is used for gripping a workpiece in the processes and markets described below. Processes that can use this electric gripper device 1 include an FA assembly process, an automobile parts assembly process, a semiconductor parts assembly process, an optical equipment alignment automation process, and a food topping process. The electric gripper device 1 can also be used in the medical and drug discovery markets.

  As shown in FIG. 1, the articulated robot 2 includes a base 6 and first to fifth arms 7 to 11 supported by the base 6. On the base 6, the 1st arm 7 is provided so that rotation is possible centering | focusing on the 1st axis line C1. The first arm 7 is provided with a second arm 8 that can swing about the second axis C2 as a swing center. The second arm 8 is provided with a third arm 9 so as to be swingable about the third axis C3 as a swing center.

  The third arm 9 is provided with a fourth arm 10 that is rotatable about the fourth axis C4. The fourth arm 10 is provided with a fifth arm 11 that can swing around a fifth axis C5 as a swing center. A tool mounting seat 12 is provided on the fifth arm 11 so as to be rotatable about the sixth axis C6. The tool mounting seat 12 is for mounting the electric gripper device 1 and other tools (not shown) according to this embodiment.

  The first to third hands 3 to 5 of the electric gripper device 1 have first claws 3a, 4a, 5a and second claws 3b, 4b, 5b for sandwiching the workpiece W, respectively. All the first claws 3a, 4a and 5a move in the same direction, as will be described in detail later. All the second claws 3b, 4b, 5b cooperate with the first claws 3a, 4a, 5a in order to grip the workpiece W and release the workpiece W in order to hold the workpiece W. , 5a move in the opposite direction. The first claws 3a, 4a, 5a and the second claws 3b, 4b, with the workpiece W positioned between the first claws 3a, 4a, 5a and the second claws 3b, 4b, 5b, When the 5b approaches each other, the workpiece W is sandwiched and gripped by the first and second claws. In the following, the direction in which the first and second claws move when sandwiching the workpiece W is simply referred to as the workpiece gripping / releasing direction.

  This workpiece gripping / releasing direction is a direction orthogonal to the sixth axis C6. In this embodiment, for convenience, as shown in FIG. 1, the direction parallel to the sixth axis C6 is simply referred to as the vertical direction, and the direction perpendicular to both the vertical direction and the workpiece gripping / releasing direction is simply left and right. It is called direction. Moreover, below, the position which adjoins the 5th arm 11 in the electric gripper apparatus 1 is demonstrated as upper.

The electric gripper device 1 according to this embodiment includes a first to third hands 3 to 5 and a driving device 22 (which drives these hands 3 to 5) on a housing 21 attached to the above-described tool mounting seat 12. Etc.) (see FIG. 4 and FIG. 5).
The housing | casing 21 is formed in the rectangular parallelepiped shape, as shown in FIGS. As shown in FIG. 7, the casing 21 according to this embodiment is formed in a hollow rectangular parallelepiped shape by combining a plurality of components. The plurality of parts include a first side plate 23 having a U-shaped cross section, a second side plate 24 that forms a square tube in cooperation with the first side plate 23, and one of the square tubes. A first lid 25 that closes the opening, and a second lid 27 that is attached to the other opening of the rectangular tube via a partition wall 26.

The partition wall 26 and the second lid body 27 close the other opening of the square tube described above. In the following description, the direction in which the open portion of the first side plate 23 having a U-shaped cross section is oriented (the direction in which the lower right side is oriented in FIG. 7) is described as the right direction.
The rectangular parallelepiped constituting the housing 21 has four side surfaces extending in the workpiece gripping / releasing direction described above. As shown in FIG. 5, these side surfaces are an upper surface 21a, a bottom surface 21b, a left side surface 21c, and a right side surface 21d.

Of the four side surfaces, the upper wall 31 having the uppermost surface 21a located in the uppermost position in FIG. 5 is provided with a mounting portion 32 to be mounted on the tool mounting seat 12 as shown in FIGS. Yes. In this embodiment, the upper wall 31 corresponds to “one side portion of the casing” according to the fourth aspect of the present invention.
As shown in FIG. 5, the first to third hands 3 to 5 include a bottom wall 33, a left side wall 34, and a right side wall corresponding to the other three side surfaces except the upper surface 21 a among the four side surfaces described above. 35. In this embodiment, the bottom wall 33, the left side wall 34, and the right side wall 35 correspond to “three side portions” in the invention of claim 4.

  The first hand 3 is provided on the bottom wall 33. The second hand 4 is provided on the left side wall 34. The third hand 5 is provided on the right side wall 35. The first to third hands 3 to 5 have the same configuration. For this reason, here, the first hand 3 will be described in detail. For the second and third hands 4 and 5, only the configuration different from that of the first hand 3 will be described, and the other configurations are denoted by the same reference numerals as those of the first hand 3, and detailed description thereof will be omitted.

  As shown in FIGS. 4 and 5, the first hand 3 has a first slider 36 and a second slider 37 along the bottom wall 33 of the housing 21. The first and second sliders 36 and 37 are supported by a single rail 38 fixed to the bottom wall 33 so as to extend in the workpiece gripping / releasing direction so as to be reciprocally movable. The first and second sliders 36 and 37 are driven along a rail 38 by being driven by a driving device 22 to be described later, and are moved toward and away from each other. Therefore, the first and second sliders 36 and 37 are supported on the outer surface of the casing 21 so as to be reciprocally movable in the workpiece gripping / releasing direction.

  The first and second sliders 36 and 37 and the rail 38 constitute a so-called linear guide. The rail 38 is formed in a shape extending from one end to the other end in the workpiece gripping / releasing direction in the housing 21, and has a groove 39 into which the first and second sliders 36 and 37 are inserted. Balls 40 are interposed between the inner side walls 39a and 39b of the groove 39 facing each other and the first and second sliders 36 and 37, respectively. The ball 40 is rotatably inserted into the ball groove 41 of the rail 38 while being held by the first and second sliders 36 and 37. The first and second sliders 36 and 37 are so-called circulating ball types in which the ball 40 circulates through circulation paths (not shown) in the first and second sliders 36 and 37. be able to.

  As shown in FIGS. 2 and 3, a first claw 3 a is attached to the first slider 36. A second claw 3 b is attached to the second slider 37. The claws 3a and 3b according to this embodiment are configured to sandwich and hold the disc-shaped workpiece W, and have a recess 42 that is opened toward one side in the left-right direction (downward in FIG. 2). . The workpiece W is sandwiched and gripped by the first and second claws 3a and 3b in a state where a part of the outer peripheral portion is inserted into the recess 42. That is, the first hand 3 includes a first slider 36 to which the first claw 3a is attached and a second slider 37 to which the second claw 3b is attached. 2 and 3 are drawn in a state where the first to third hands 3 to 5 each grip the work W so that the configuration can be easily understood. However, the electric gripper device 1 grips the workpiece W using only one of the first to third hands 3 to 5.

The first and second claws 3a and 3b of the first hand 3 grip a relatively small workpiece W, and are near the ends of the first slider 36 and the second slider 37 that are close to each other. It is positioned.
The first claws 4a and 5a and the second claws 4b and 5b of the second and third hands 4 and 5 grip a relatively large workpiece W. The first slider 36 and the second slider 37 is positioned in the vicinity of the spaced apart ends. Note that the distance between the first claw and the second claw (the distance when the first slider 36 is closest to the second slider 37) can be set to a different distance for each hand. Moreover, although not shown in figure, the shape of a 1st nail | claw and a 2nd nail | claw can be changed for every hand. By adopting this configuration, it is possible to grip workpieces (squares, circles, etc.) having different shapes.

  As shown in FIGS. 4 and 5, the first and second sliders 36 and 37 are each provided with a pin 43 for transmitting power from the driving device 22 described later. The pin 43 is fixed to the first and second sliders 36 and 37, and is passed through the through hole 44 of the rail 38 and the through hole 45 of the bottom wall 33 from the first and second sliders 36 and 37. It extends inside the housing 21. The through holes 44 and 45 are formed long in the workpiece gripping / release direction in order to allow the pin 43 to move in the workpiece gripping / release direction.

  The tip of the pin 43 provided on the first slider 36 is fixed to the first moving member 51 provided in the housing 21. The tip of the pin 43 provided on the second slider 37 is fixed to a second moving member 52 provided in the housing 21. For this reason, the first slider 36 is connected to the first moving member 51 through the pin 43, and the second slider 37 is connected to the second moving member 52 through the pin 43.

  As shown in FIG. 5 and FIG. 6, the first moving member 51 and the second moving member 52 extend to the left from the main body portions 51a and 52a extending in the vertical direction and the upper end portions of the main body portions 51a and 52a, respectively. Left arm portions 51b and 52b, and right arm portions 51c and 52c extending rightward from the upper ends of the main body portions 51a and 52a are provided. The pin 43 that connects the first and second sliders 36 and 37 of the first hand 3 and the first and second moving members 51 and 52 is the lower end portion of the main body portions 51a and 52a, and left and right. Connected to the center of the direction.

  A ball screw shaft 53 (to be described later) and first and second ball screw nuts 54 and 55 that are screwed into the ball screw shaft 53 pass through the center portions of the main body portions 51a and 52a in the vertical direction. The first ball screw nut 54 passes through the first moving member 51. The second ball screw nut 55 passes through the second moving member 52. The first moving member 51 and the second moving member 52 are supported by a ball screw shaft 53 via first and second ball screw nuts 54 and 55.

The distal end portions of the left arm portions 51 b and 52 b of the first and second moving members 51 and 52 are formed in a shape that can be received in a through hole 56 formed in the left wall 34 of the housing 21. A pin 43 of the second hand 4 is connected to the tip portion. The pin 43 is fixed to the distal end portion of the left arm portion 51b so as to penetrate through the pin 43 in the left-right direction.
The distal end portions of the right arm portions 51 c and 52 c of the first and second moving members 51 and 52 are formed in a shape that is accommodated in a through hole 57 formed in the right wall 35 of the housing 21. A pin 43 of the third hand 5 is connected to the tip portion. The pin 43 is fixed to the distal end portions of the right arm portions 51c and 52c in a state of penetrating in the left-right direction.

Therefore, all the first sliders 36 are connected to the first moving member 51, and all the second sliders 37 are connected to the second moving member 52.
As shown in FIG. 4, the ball screw shaft 53 that supports the first moving member 51 and the second moving member 52 extends in the workpiece gripping / releasing direction (left-right direction in FIG. 4). The first lid 25 and the partition wall 26 of the housing 21 are rotatably supported by bearings 58 and 59, respectively. The bearing 58 is urged toward the partition wall 26 by a wave washer 65 provided between the lid body 25 and the bearing 58. When the pressing force of the wave washer 65 is applied to the bearing 58, the pressing force is transmitted from the bearing 58 to the bearing 59 via the ball screw shaft 53, and the bearing 59 is pressed against the partition wall 26. For this reason, the ball screw shaft 53 and the bearings 58 and 59 are supported by the housing 21 in a state where there is no backlash in the workpiece gripping / releasing direction. In this embodiment, the ball screw shaft 53 corresponds to the “drive shaft” in the present invention.

  The first and second sliders 36 and 37 of the first hand 3 described above are disposed near the lower portion of the ball screw shaft 53 as shown in FIG. The first and second sliders 36 and 37 of the second hand 4 are arranged in the vicinity of the left side of the ball screw shaft 53. The first and second sliders 36 and 37 of the third hand 5 are disposed near the right side of the ball screw shaft 53. That is, the first and second sliders 36 and 37 of the first to third hands 3 to 5 according to this embodiment are configured so that the ball screw shaft 53 and the first and second sliders 36 and 37 are as shown in FIG. It is provided at each of a plurality of adjacent positions.

A first screw portion 53a is formed on one end side of the ball screw shaft 53 in the axial direction, and a second screw portion 53b is formed on the other end side. The first screw portion 53a and the second screw portion 53b are formed so that the screw directions are opposite to each other.
A first ball screw nut 54 is supported by the first screw portion 53a in a state of being screwed. The rotation of the first ball screw nut 54 is regulated by the casing 21 connected through the first moving member 51, the three pins 43, and the first slider 36 and the rail 38. The

A second ball screw nut 55 is supported by the second screw portion 53b in a state of being screwed. The rotation of the second ball screw nut 55 is restricted by the casing 21 connected via the second moving member 52, the three pins 43, and the members such as the second slider 37 and the rail 38. The
For this reason, the first moving member 51 and the second moving member 52 move in a direction approaching each other when the ball screw shaft 53 rotates forward, for example, and move away from each other when the ball screw shaft 53 reverses. Move to.

  In this way, the driving device 22 drives the first moving member 51 and the second moving member 52 in the opposite directions by the single ball screw shaft 53. The driving device 22 according to this embodiment includes the above-described ball screw shaft 53, first and second ball screw nuts 54 and 55, a motor 61 disposed in the upper portion of the housing 21, and the motor 61. A ball screw shaft transmission mechanism 62 for connecting the ball screw shaft 53 is provided.

  The motor 61 is a servo motor having an encoder 63, and is disposed between the mounting portion 32 (upper wall 31) attached to the tool mounting seat 12 of the robot 2 in the housing 21 and the ball screw shaft 53. Further, as shown in FIG. 4, the motor 61 is fixed to the partition wall 26 with its axis lined in the workpiece gripping / release direction and the rotating shaft 61a protruding from the partition wall 26 toward the outside of the housing 21. Yes. Although not shown, the motor 61 is connected to the control device via a cable. The cable extends from the inside of the casing 21 into the base 6 through the through hole 64 of the upper wall 31 and the first to fifth arm portions 7 to 11 of the robot 2. The operation of the motor 61 is controlled by a control device.

  The transmission mechanism 62 is installed between a driving pulley 62a attached to the rotating shaft 61a of the motor 61, a driven pulley 62b attached to the shaft end of the ball screw shaft 53, and the pulleys 62a and 62b. The belt 62c is passed. The transmission mechanism 62 transmits the rotation of the motor 61 to the ball screw shaft 53 via the driving pulley 62a, the belt 62c, and the driven pulley 62b. For this reason, the ball screw shaft 53 rotates as the motor 61 rotates, and the first and second moving members 51 and 52 are driven. In this embodiment, the transmission mechanism 62 corresponds to the “ball screw shaft transmission mechanism” according to the third aspect of the present invention.

  When the first and second moving members 51 and 52 move in a direction approaching each other, the first to third hands 3 to 5 connected to the moving members 51 and 52 via the pins 43 are connected. As the first and second sliders 36 and 37 approach each other, the first claws 3a, 4a and 5a of the first to third hands 3 to 5 and the second claws 3b, 4b and 5b The interval is narrowed. On the other hand, the first and second moving members 51 and 52 move in a direction away from each other, whereby the first and second sliders 36 and 37 of the first to third hands 3 to 5 are separated from each other. Accordingly, the distance between the first claws 3a, 4a, 5a of the first to third hands 3-5 and the second claws 3b, 4b, 5b is increased. In this embodiment, the first and second ball screw nuts 54 and 55, the first and second moving members 51 and 52, and the members 43 such as the pins 43 of each slider are referred to as “rotation”. A slider transmission mechanism that converts the rotation of the shaft into a parallel movement in the workpiece gripping / releasing direction and transmits it to the first slider and the second slider is configured. Further, the first and second moving members 51 and 52 and the pin 43 of each slider are connected to all the first and second sliders 36 and 37 of the first to third hands 3 to 5 from the ball screw shaft 53. Each of them constitutes a “transmission member” that transmits power.

  In the electric gripper device 1 configured as described above, hands (first to third hands 3 to 5) are provided at a plurality of positions of the casing 21, that is, at three locations. For this reason, by changing the position of the casing 21 by rotating the axis C5, the axis C6, or the like of the robot 2, it is possible to select a hand suitable for the workpiece W among the first to third hands 3-5. it can. The first and second claws of the first to third hands 3 to 5 move in the workpiece gripping / release direction as the ball screw shaft 53 rotates. For this reason, it becomes possible to drive a plurality of hands with one driving device 22. This electric gripper device 1 is lighter because it requires only one drive device 22 and a cable compared to a conventional device provided with an actuator for each hand. It will be compact. Further, the installation work of the driving device 22 and the cable can be easily performed, and the control of the driving device 22 can be easily performed.

  Therefore, according to this embodiment, it is possible to provide an electric gripper device that is light and compact, and can easily install and control a control cable, despite being equipped with a plurality of hands. be able to. The tip of the robot hand equipped with this electric gripper device is small and light.

The drive device 22 according to this embodiment includes a motor 61 connected to a ball screw shaft 53 via a transmission mechanism 62. The motor 61 is disposed between the mounting portion 32 attached to the tool mounting seat 12 in the housing 21 and the ball screw shaft 53.
For this reason, since the motor 61 is arrange | positioned in the position which does not block operation | movement of the 1st and 2nd moving members 51 and 52, a compact electric gripper apparatus can be provided.

  In particular, according to this embodiment, as shown in FIG. 5, the left arm portions 51a and 52a are housed in the through holes 56 of the left side wall 34 of the housing 21, and the right arm portions 51c and 52c have the distal ends. The housing 21 is accommodated in the through hole 56 of the right side wall 35. For this reason, since the motor 61 can be disposed at a low position while avoiding interference between the left arm portions 51b and 52b and the right arm portions 51c and 52c and the motor 61, the casing 21 is formed more compactly in the vertical direction. be able to.

The casing 21 according to this embodiment is formed in a rectangular parallelepiped shape having four side surfaces extending in the workpiece gripping / releasing direction. The attachment portion 32 attached to the tool attachment seat 12 in the housing 21 is provided on the upper wall 31 of the housing 21 having one of the four side surfaces. The first and second sliders 36 and 37 are respectively provided on the bottom wall 33, the left side wall 34, and the right side wall 35 corresponding to the other three side surfaces of the four side surfaces of the housing 21. That is, these hands are provided at three locations of the casing 21.
For this reason, according to this embodiment, an electric gripper device having three hands can be easily realized.

(Second Embodiment)
The electric gripper device according to the present invention can be configured as shown in FIGS. In these drawings, members that are the same as or equivalent to those described with reference to FIGS. 1 to 7 are given the same reference numerals, and detailed descriptions thereof are omitted as appropriate.
An electric gripper device 71 shown in FIG. 8 is obtained by adding a fourth hand 72 to the casing 21 of the electric gripper device 1 shown in the first embodiment.

  The fourth hand 72 includes a rail base 74 attached to the second lid body 27 of the housing 21 via a plate-like support member 73, and three finger blocks 75 provided on the rail base 74. I have. These finger blocks 75 hold the workpiece W (not shown) sandwiched from three directions orthogonal to the “work gripping / release direction” in the first embodiment, and are provided on the rail base 74. The three rails 76 are movably supported.

  The three finger blocks 75 are arranged so that the relative angle between the finger blocks 75 is 120 degrees when viewed from the workpiece gripping / release direction. In this embodiment, these finger blocks 75 correspond to the “claw member” in the invention of claim 5.

As shown in FIG. 9, a disc-shaped cam member 81 is provided inside the rail base 74. The cam member 81 is rotatably supported by a support member 73 via a bearing 82. That is, the cam member 81 is rotatably supported on the side portion of the housing 21 that is positioned at one end side in the workpiece gripping / release direction with the workpiece gripping / release direction as the axial direction.
The three finger blocks 75 described above are arranged in a radial pattern around the axis of the support member 73 when viewed from the workpiece gripping / releasing direction, and are movable in the direction of contact with and away from the axis.

  Further, the cam member 81 is formed with three spiral cam grooves 83 concentrically as shown in FIG. These cam grooves 83 are formed in a shape along the so-called Archimedean spiral. One end of a pin-like cam follower 84 is movably fitted in these cam grooves 83. The other end sides of these cam followers 84 pass through guide holes 85 (see FIG. 8) of the rail base 74 and are fixed to the finger block 75. The guide hole 85 is formed in a shape extending in parallel with the rail 76 with an opening width into which the cam follower 84 is fitted.

  The cam member 81 according to this embodiment constitutes a gear having teeth 86 on the outer peripheral portion. As shown in FIG. 9, a pinion 87 is engaged with the teeth 86. The pinion 87 is rotatably supported by a support member 73 by a bearing 88 in a state of being located on the same axis as the rotation shaft 61 a of the motor 61. The pinion 87 is connected to the rotating shaft 61 a of the motor 61 via a coupling 89. In this embodiment, the power of the driving device 22 (not shown) is generated from a rotating shaft 61a of the motor 61 through a coupling 89, a pinion 87, and a tooth 86 provided on the outer peripheral portion of the cam member 81. It is transmitted to the cam member 81 via the member transmission mechanism 90.

  In the fourth hand 72 according to this embodiment, when the pinion 87 rotates integrally with the motor 61, the cam member 81 rotates, and the cam groove 83 converts the rotational motion into a linear motion, so that the cam follower 84 and the finger block are rotated. 75 moves in the radial direction of the cam member 81. As a result, the interval between the three finger blocks 75 changes, and the workpiece W can be gripped or released by these finger blocks 75.

Moreover, according to this embodiment, the 4th hand 72 which has the three finger blocks 75 is provided in the housing | casing 21 besides the 1st-3rd hands 3-5 mentioned above. The fourth fourth hand 72 is driven by the driving device 22 common to the first to third hands 3 to 5.
Therefore, according to this embodiment, it is possible to provide an electric gripper device that can drive four hands with one driving device 22.

According to this embodiment, since the rotation angle of the motor 61 and the movement amount (hand opening / closing stroke) of the three finger blocks 75 have a linear relationship, the first to third hands 3 to 5 and The fourth hand 72 can be controlled by the same control method.
In this embodiment, an example in which three finger blocks 75 are used has been shown. However, the present invention is not limited to such a limitation. That is, by changing the number of cam grooves 83 provided in the cam member 81, the number of finger blocks 75 can be changed to two or four.

(Third embodiment)
The electric gripper device according to the present invention can be configured as shown in FIGS. In these drawings, the same or equivalent members as those described with reference to FIGS. 1 to 10 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.
The electric gripper device 101 according to this embodiment differs from the electric gripper devices 1 and 71 described with reference to FIGS. 1 to 10 only in the configuration of the drive device 102, and the other configurations are the same.

  The casing 21 of the electric gripper device 101 according to this embodiment is formed in a hollow cubic shape that is long in the vertical direction of FIG. The housing 21 shown in FIG. 11 is drawn with a reduced number of parts so that the structure can be easily understood, and the actual housing 21 is configured by combining a plurality of members with bolts. An attachment portion 32 that is attached to the tool attachment seat 12 of the articulated robot 2 is provided at one end portion in the longitudinal direction of the casing 21 (the upper end portion in FIG. 11). In the following, for convenience, the vertical direction in FIG. 11 will be described as the vertical direction of the electric gripper device 101, and the horizontal direction in FIG. 11 will be described as the horizontal direction of the electric gripper device 101.

  The first hand 3 is provided on the lower surface of the housing 21 that faces the upper surface having the mounting portion 32. Of the four side surfaces of the housing 21 extending in the vertical direction, second and third hands 4 and 5 are provided on the left side surface and the right side surface facing each other. In FIG. 11, the nails for gripping the workpiece are omitted. Of these first to third hands 3 to 5, the first hand 3 is different in configuration from the second and third hands 4 and 5.

  The first hand 3 according to this embodiment has a structure equivalent to that of the fourth hand 72 shown in FIG. 8, and has three finger blocks 75 as shown in FIG. These finger blocks 75 are movably supported on rails 76 and are connected to a disk-shaped cam member 81 via pins 84. In this embodiment, these finger blocks 75 correspond to “a plurality of claw members” according to the seventh aspect of the present invention. The rail 76 is fixed to a rail base 74 attached to the housing 21. For this reason, these finger blocks 75 are supported by the housing 21 through a rail 76 and a rail base 74 so as to be movable toward and away from an axis C7 (see FIG. 11) of a cam member 81 described later. ing.

  The cam member 81 according to this embodiment has a drive system configuration different from that shown in FIG. The cam member 81 is driven through a first driven shaft 103 provided at the shaft center portion. The first driven shaft 103 is fixed to the axial center portion of the cam member 81 so as to be positioned on the same axis as the cam member 81. The first driven shaft 103 is rotatably supported by the housing 21 by a bearing 104.

  The axial direction of the first driven shaft 103 is a direction parallel to the vertical direction in FIG. 11 and is a direction orthogonal to the surface of the attachment portion 32. The distal end portion (the upper end portion in FIG. 11) of the first driven shaft 103 is connected to a drive shaft 106 of the drive device 102 described later via a coupling 105. That is, the cam member 81 is provided in a state of rotating integrally with the distal end portion of the drive shaft 106. As shown in FIG. 13, the cam member 81 has three spiral cam grooves 83 formed concentrically. The pin 84 of each finger block 75 is movably fitted in the cam groove 83. For this reason, when the cam member 81 rotates, the three finger blocks 75 are simultaneously brought into and out of contact with the axis C <b> 7 of the cam member 81.

  The second and third hands 4 and 5 have the same configuration. The second and third hands 4 and 5 include a rail 38 attached to the housing 21 via a rail base 111, and first and second sliders 36, movably supported on the rail 38, 37 (see FIG. 14). A ball 40 is interposed between the rail 38 and the first and second sliders 36 and 37. The direction (work gripping / release direction) in which the first and second sliders 36 and 37 move is a direction orthogonal to the paper surface of FIG. In other words, the first and second sliders 36 and 37 are in a direction orthogonal to the axis C7 of the first driven shaft 103 described above, and the direction in which the second hand 4 and the third hand 5 are arranged. It is a direction orthogonal to (left-right direction in FIG. 11).

  The first and second sliders 36 and 37 are each provided with a pin 43 extending into the housing 21. The pin 43 is inserted into the through hole 44 of the rail 38 and extends into the rail base 111, and is connected to a disk-shaped cam member 112 accommodated inside the rail base 111. In this embodiment, the pin 43 of the first slider 36 constitutes the “first cam follower” in the sixth aspect of the invention, and the pin 43 of the second slider 37 is the invention of the sixth aspect. This constitutes a “second cam follower”.

  As shown in FIG. 15, the cam member 112 is formed with two spiral cam grooves 113 concentrically. The pin 43 of the first slider 36 and the pin 43 of the second slider 37 are movably fitted in the cam groove 113, respectively. These cam grooves 113 are formed in a shape along the so-called Archimedes spiral, similarly to the cam grooves 83 shown in FIGS. Therefore, when the cam member 112 is rotated forward or reverse, the first and second sliders 36 and 37 are simultaneously moved in the workpiece gripping direction or the workpiece releasing direction.

  A second driven shaft 114 is provided on the same axis along the axial center of the cam member 112 of the second hand 4. A third driven shaft 115 is provided in the axial center portion of the cam member 112 of the third hand 5 so as to be positioned on the same axis. These second and third driven shafts 114 and 115 respectively extend from the cam member 112 toward the inside of the housing 21 and are rotatably supported by the housing 21 by bearings 116.

  A driven bevel gear 121 for the second hand is attached to the tip of the second driven shaft 114. A driven bevel gear 122 for the third hand is attached to the tip of the third driven shaft 115. That is, in these second and third driven shafts 114 and 115, the driven side bevel gears 121 and 122 are attached to one end portion, and the cam portion 112 is provided at the other end portion. The housing 21 is rotatably supported so as to be positioned in the vicinity of the hand 4 or the third hand 5. The driven side bevel gears 121 and 122 mesh with a driving side bevel gear 123 of the driving device 102 described later.

  The driving device 102 according to this embodiment simultaneously drives the first to third hands 3 to 5 using a motor 124 provided at the end of the housing 21 opposite to the first hand 3 as a power source. . The motor 124 is supported by the casing 21 with the longitudinal direction of the casing 21 as the axial direction. The drive shaft 106 connected to the first driven shaft 103 of the first hand 3 is constituted by the rotation shaft of the motor 124. That is, the drive shaft 106 is rotatably supported by the housing 21. The drive shaft 106 is a central portion of the housing 21 and is disposed between the second hand 4 and the third hand 5. For this reason, the second hand 4 and the third hand 5 are provided at a plurality of positions adjacent to the drive shaft 106 when viewed from the axial direction of the drive shaft 106.

  The drive device 102 according to this embodiment includes the above-described motor 124 and drive shaft 106, a slider transmission mechanism 125 including a drive-side bevel gear 123 fixed to an intermediate portion of the drive shaft 106, and the like. The slider transmission mechanism 125 has a function of transmitting power from the drive shaft 106 to all of the first and second sliders 36 and 37 by a transmission member described later. The transmission member includes a drive-side bevel gear 123, two driven bevel gears 121 and 122 meshed with the drive-side bevel gear 123, and second and second rotating together with the driven bevel gears 121 and 122. Third driven shafts 114 and 115, two cam members 112 and 112 provided on the second and third driven shafts 114 and 115, respectively, and first and first cams connected to the cam members 112 And pins 43 and 43 for each of the two sliders 36 and 37. Therefore, the slider transmission mechanism 125 converts the rotation of the drive shaft 106 into a parallel movement in the workpiece gripping / releasing direction and transmits it to the first slider and the second slider.

Accordingly, also in this embodiment, a plurality of hands (second and third hands 4 and 5) can be driven by one driving device 102. Therefore, the first and second embodiments are used. The same effect as when using it is obtained.
The rotation of the drive shaft 106 is converted into parallel movement in the workpiece gripping / release direction by the first driven shaft 103, the cam member 81, and the pin 84, and transmitted to the three finger blocks 75 of the first hand 3. Is done. For this reason, according to this embodiment, the electric gripper device 101 in which three hands (first to third hands 3 to 5) are simultaneously driven is less expensive than the case of adopting the first embodiment. Can be provided. The reason for the low cost is that the rotation of one drive shaft 106 is converted into a reciprocating motion and transmitted to the first to third hands 3 to 5 by simple shafts (first to third followers). Shafts 103, 114, 115), bevel gears (drive side bevel gear 123, driven bevel gears 121, 122), cam members (cam members 81, 112), pins (pins 84, 43), etc. are used. This is because these members are less expensive than the ball screw mechanism.

  In the third embodiment, among the four side surfaces orthogonal to the side surface having the attachment portion 32 in the housing 21, the second hand 4 is provided on the left side surface and the third hand 5 is provided on the right side surface. An example is shown. However, the present invention is not limited to such a limitation, and hands can be provided on each of the remaining two side surfaces among the four side surfaces.

  DESCRIPTION OF SYMBOLS 1,71,101 ... Electric gripper apparatus 101, 2 ... Articulated robot, 3 ... 1st hand 3, 4 ... 2nd hand 4, 5 ... 3rd hand 5, 3a, 4a, 5a ... 1st Claw, 3b, 4b, 5b ... second claw, 12 ... tool mounting seat, 21 ... casing 21, 21a, 21b, 21c, 21d ... side, 22 ... driving device 102, 27 ... second lid (side Part), 31 ... upper wall (one side part), 32 ... attachment part, 33 ... bottom wall (side part), 34 ... left side wall (side part), 35 ... right side wall (side part), 36 ... first Slider, 37 ... second slider, 43, 84 ... pin, 51 ... first moving member, 52 ... second moving member, 53 ... ball screw shaft, 61, 124 ... motor, 62 ... transmission mechanism (ball screw Shaft transmission mechanism), 72... Fourth hand, 75... Finger block 75 (claw member), 81 and 112. 83, 113 ... cam groove, 84 ... cam follower, 90 ... cam member transmission mechanism, 103 ... first driven shaft, 106 ... drive shaft, 114 ... second driven shaft, 115 ... third driven shaft, 121, 122 ... driven side bevel gear, 123 ... drive side bevel gear, 125 ... slider transmission mechanism, W ... work.

Claims (7)

A housing that can be attached to the tool mounting seat of the robot;
A first slider having a first claw for gripping the workpiece, supported on the outer surface of the housing so as to be reciprocally movable in the workpiece gripping / release direction;
A second claw that sandwiches the workpiece in cooperation with the first claw, and is capable of reciprocating in the workpiece gripping / releasing direction at a position adjacent to the first slider on the outer surface of the housing. A second slider which is supported by the first slider and forms a hand in cooperation with the first slider;
A driving device for driving the first and second sliders in opposite directions;
The driving device includes:
A drive shaft rotatably supported by the housing;
A motor for driving the drive shaft;
A slider transmission mechanism that converts the rotation of the drive shaft into a parallel movement in the workpiece gripping / releasing direction and transmits the translation to the first slider and the second slider;
The hand is provided at each of a plurality of positions adjacent to the drive shaft as viewed from the axial direction of the drive shaft,
The power transmission mechanism is an electric gripper device having a power transmission member that transmits power from the drive shaft to all the first and second sliders of each hand. The electric gripper device according to claim 1, wherein
The drive shaft is constituted by a ball screw shaft,
The ball screw shaft has a first screw portion and a second screw portion in which screw directions are opposite to each other,
The transmission mechanism is
A first ball screw nut threadably engaged with the first thread portion;
A second ball screw nut threadably engaged with the second thread portion;
A first moving member as the transmission member for connecting the first ball screw nut and all the first sliders;
An electric gripper device comprising: a second moving member as the transmission member that connects the second ball screw nut and all the second sliders. The electric gripper device according to claim 2,
The drive device has a transmission mechanism for a ball screw shaft that connects the motor and the drive shaft,
The electric gripper device, wherein the motor is disposed between an attachment portion attached to the tool attachment seat in the housing and the ball screw shaft. In the electric gripper device according to any one of claims 1 to 3,
The housing is formed in a rectangular parallelepiped shape having four side surfaces extending in the workpiece gripping / releasing direction,
The mounting portion attached to the tool mounting seat in the housing is provided on one side of the housing having one of the four side surfaces,
The electric gripper device, wherein the first and second sliders are respectively provided on three side portions corresponding to the other three side surfaces of the four side surfaces. The electric gripper device according to claim 4,
A plurality of spiral cam grooves are formed concentrically, and are supported rotatably on the side portion of the housing located on one end side in the workpiece gripping / release direction with the workpiece gripping / release direction as an axial direction. A cam member;
A plurality of claw members having a cam follower movably inserted in the cam groove and supported by the housing so as to be movable toward and away from the axis of the cam member;
An electric gripper device comprising: a cam member transmission mechanism for transmitting power from the drive device to the cam member. The electric gripper device according to claim 1, wherein
The drive shaft has a drive side bevel gear,
The transmission mechanism is
A plurality of driven bevel gears meshing with the drive bevel gear;
A plurality of spiral cam grooves are formed concentrically, and a plurality of cam members provided for each driven bevel gear;
The driven bevel gear is provided at one end and the cam member is provided at the other end, and a plurality of driven followers rotatably supported by the housing so that the cam member is positioned in the vicinity of each hand. The axis,
A first cam follower provided on the first slider and movably inserted in the cam groove;
An electric gripper device having a second cam follower provided on the second slider and movably inserted in the cam groove. The electric gripper device according to claim 6,
A cam member provided in a state of rotating integrally with a tip end portion of the drive shaft, and a plurality of spiral cam grooves formed concentrically;
A plurality of claw members, each having a cam follower movably inserted in the cam groove, and supported by the housing in a direction to move toward and away from the axis of the cam member; Electric gripper device.

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