JP2012101316A - Robot hand - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress restrictions imposed on the movable range of a robot hand or a robot arm by wiring, and to easily change a type of a grip.SOLUTION: In an assembly robot, a grip control signal and a coupling part control signal output from a control unit to a fixed section 31 are transmitted to a rotational section 32 via s slip ring 35, and a grip state signal output from a grip state acquisition section is transmitted from the rotational section 32 to the fixed section 31 via the slip ring 35 to be transmitted to the control unit. Thus, exposure of signal transmission wiring between the fixed section 31 and the rotational section 32 to the outside is suppressed, and restrictions imposed on the movable range of the robot hand or the robot arm by wiring is suppressed. In the robot hand, a hand leading end including a grip and a gripping state acquisition section is detachably fixed to the rotational unit 32 via a coupling section 323, and thus a type of a grip is easily changed.

Description

  The present invention relates to a robot hand provided at the tip of a robot arm of an assembly robot.

  2. Description of the Related Art Conventionally, an assembly robot has been used in an automatic assembly line or the like. In an assembly robot, a robot hand that grips a workpiece is connected to a robot arm, and can be moved three-dimensionally. In the robot hand, the workpiece is gripped and released by driving the gripper using compressed air.

  In the robot of Patent Document 1, a manifold is attached to the tip of a robot arm so as not to rotate, and a hand is attached to the manifold via a hand holder. The compressed air hose for driving the hand is connected to the outer surfaces of the hand and the hand holder, and an internal flow path continuous from the hose is formed inside the hand holder and the manifold. In the manifold, a plurality of solenoid valves for controlling the supply and discharge of compressed air are arranged in an annular shape. The plurality of solenoid valves are connected to an interface unit provided in the manifold via a cable, and the interface unit is connected to a control unit of the robot via a cable.

  In the robot of Patent Document 2, a cylindrical fixed flange is fixed to the tip of the robot arm in a non-rotatable manner, and the rotation shaft inserted into the shaft hole of the fixed flange is fixed to the tip of the rotation list of the robot arm by bolting. Is done. A plurality of gripping portions are connected to the turret plate provided on the distal end side of the rotating shaft. A compressed air hose for driving the grip portion is connected to the outer surface of the fixed flange, and the compressed air is guided toward the outer surface of the rotating shaft by a flow path formed in the fixed flange. An annular recess is formed on the outer surface of the rotating shaft, and the compressed air is an annular channel formed by the recess and the inner surface of the fixing flange, and a channel extending in the axial direction from the channel. Is guided to the turret plate and supplied to each of the plurality of gripping portions via a plurality of electromagnetic valves.

  In addition, a current collecting ring is provided on the outer surface of the rotating shaft, and a slip ring for electrically connecting the fixing flange and the rotating shaft is formed by providing a current collecting brush in contact with the current collecting ring on the fixing flange. Is done. In the robot of Patent Document 2, a plurality of slip rings are arranged in the axial direction of the rotating shaft, and electric power and control signals supplied from the power supply unit to the fixed flange via the cable are transmitted via these slip rings. Sent to multiple solenoid valves.

Japanese Patent No. 3172028 JP 2009-269125 A

  By the way, in the robot of patent document 1, in order to transmit electric power and a control signal from the control part to the plurality of solenoid valves of the robot hand, the control part and the robot hand are connected by a cable. It is exposed outside the hand or robot arm. Assuming that the robot hand of the robot disclosed in Patent Document 1 is rotatable, the robot hand can be rotated within a rotatable range so that the cable connecting the robot hand and the robot arm is not cut by the rotation of the robot hand. Big restrictions are set.

  In the robot of Patent Document 2, since the turret plate provided with the grip portion is fixed to the robot arm by bolting, the type of the grip portion cannot be easily changed. In addition, since a plurality of slip rings are arranged in the axial direction of the rotating shaft, if the amount of power and signal exchanged between the turret plate and the fixed flange increases and the slip ring becomes larger, the rotating shaft becomes longer. The robot becomes larger.

  The present invention has been made in view of the above-described problems, and has as its main purpose to suppress the movement range of the robot hand and the robot arm from being restricted by wiring and to easily change the type of the gripping portion.

  The invention according to claim 1 is a robot hand provided at a tip of a robot arm of an assembly robot, and is fixed to a rotation portion into which a rotation shaft is inserted, and rotates around the rotation shaft adjacent to the fixing portion. A rotating portion; a tip portion detachably attached to the rotating portion; and a slip ring that is disposed between the fixed portion and the rotating portion to transmit an electrical signal, and the tip portion grips a workpiece. A gripping state acquiring unit that acquires a gripping state of a workpiece by the gripping unit, and the rotating unit includes a detachable mechanism that detachably fixes the tip end portion, and from the control unit to the fixing unit. The output signal for controlling the gripping part and the signal for switching the fixing and separation of the tip part by the attachment / detachment mechanism are respectively transmitted from the fixing part to the gripping part via the slip ring. Is transmitted to the spare the detachable mechanism, the signal output from the gripping state acquisition unit is sent from the rotating part to the said control unit is transmitted to through the slip ring the fixed part.

  A second aspect of the present invention is the robot hand according to the first aspect, wherein the electrical contact in the slip ring is located in a plane perpendicular to the rotation axis.

  A third aspect of the present invention is the robot hand according to the first or second aspect, wherein the gripping portion is mediated by a fluid in a gripping channel formed inside the rotating portion and the tip portion. Driven.

  A fourth aspect of the present invention is the robot hand according to any one of the first to third aspects, wherein the attachment / detachment mechanism is provided via a fluid in an attachment / detachment passage formed inside the rotating portion. Driven.

  The invention according to claim 5 is the robot hand according to any one of claims 1 to 4, wherein the wiring for guiding the signal output from the gripping state acquisition unit to the slip ring includes the tip and It arrange | positions inside the said rotation part.

  According to the present invention, it is possible to prevent the movable range of the robot hand and the robot arm from being limited by the wiring, and to easily change the type of the gripper.

It is a side view of the assembly robot which concerns on one embodiment. It is a fragmentary sectional view near a hand main-body part. It is a bottom view of a hand main-body part. It is a side view of a hand tip part. It is a bottom view of a hand tip part. It is a front view which expands and shows the holding part vicinity. It is a side view which expands and shows the holding part vicinity. It is a figure which shows a holding part and a holding state acquisition part. It is a figure which shows a holding part and a holding state acquisition part. It is a figure which shows a holding part and a holding state acquisition part.

  FIG. 1 is a side view of an assembly robot 1 according to an embodiment of the present invention. The assembly robot 1 is an industrial robot used in an automatic assembly line or the like that automatically assembles an assembly composed of a large number of parts. The assembly robot 1 in FIG. 1 includes a robot arm 11 having multiple degrees of freedom (for example, 6 degrees of freedom), a robot hand 2 provided at the tip of the robot arm 11, and a control unit 12 responsible for overall control of the assembly robot 1. The robot arm 2 can move the robot hand 2 three-dimensionally. The robot hand 2 includes a hand main body portion 3 attached to the robot arm 11 and a hand tip portion 4 detachably attached to the hand main body portion 3. The hand tip portion 4 has a plurality of gripping portions for gripping a workpiece. 5 is provided.

  FIG. 2 is a partial cross-sectional view of the vicinity of the hand main body 3 with the hand tip 4 removed, and FIG. 3 is a bottom view of the hand main body 3. FIG. 2 shows a cross section at the position of the electromagnetic valve 33. As shown in FIG. 2, the hand main body 3 is in the vertical direction of the robot hand 2 (the direction corresponds to the vertical direction in FIG. 2 and does not always coincide with the direction of gravity. The same applies to FIG. 4). A fixed portion 31 and a rotating portion 32 are provided centering on an extending central axis J1. The fixing portion 31 has a substantially cylindrical shape having a through-hole 310 penetrating in the vertical direction in the center portion, and is fixed to the frame at the tip portion of the robot arm 11 so as not to rotate. The rotating unit 32 includes a substantially disc-shaped rotating unit main body 321, a rotating shaft 322 (hereinafter referred to as “hand rotating shaft 322”) that protrudes upward from the center of the upper surface of the rotating unit main body 321 in FIG. The coupling unit 323 protrudes downward from the center of the lower surface of the rotating unit main body 321. The hand rotation shaft 322 and the coupling portion 323 have a substantially cylindrical shape with the central axis J1 as the center.

  The hand rotation shaft 322 is inserted into the through-hole 310 of the fixed portion 31 and is provided at the distal end portion of the robot arm 11 (the rotation shaft of the robot arm 11, hereinafter referred to as “arm rotation shaft 111”). )). In the state where the hand rotation shaft 322 is connected to the arm rotation shaft 111, the center axis of the arm rotation shaft 111 coincides with the center axis J1 of the hand rotation shaft 322. J1 is attached. In the assembly robot 1, the rotating unit main body 321 of the rotating unit 32 is adjacent to the lower side of the fixed unit 31, and the rotating unit 32 is rotated by the arm rotating shaft 111 and the hand rotating shaft 322 by rotating the arm rotating shaft 111. And the arm rotation shaft 111 around the center axis (that is, the center axis J1).

  The coupling portion 323 is inserted into the coupling hole 42 (see FIG. 4) of the hand distal end portion 4 and coupled to the coupling hole 42 when the hand distal end portion 4 (see FIG. 4) is attached to the rotating portion 32. Further, the hand tip 4 is detached from the rotating part 32 by releasing the connection between the connecting part 323 and the connecting hole 42. In the robot hand 2, the coupling portion 323 is an attachment / detachment mechanism that detachably fixes the hand tip portion 4.

  The robot hand 2 further includes a slip ring 35 that is disposed between the fixed portion 31 and the rotating portion 32 and transmits an electrical signal. The slip ring 35 is a so-called disk-type slip ring, and includes an annular plate-like disk substrate 351 fixed to the hand rotation shaft 322 and a plurality of contacts 352 fixed to the fixing portion 31. The contact 352 is connected to the control unit 12 (see FIG. 1) via the fixed unit 31 and the wiring arranged inside the robot arm 11.

  The disk substrate 351 is arranged perpendicular to the central axis J1 of the hand rotation shaft 322, and a plurality of rings arranged concentrically around the hand rotation shaft 322 are provided on the upper surface of the disk substrate 351. The plurality of rings are electrically insulated from each other, and the contact 352 contacts each of the plurality of rings, thereby supplying power from the fixed portion 31 to the rotating portion 32 and the fixed portion 31 and the rotating portion. Signals are exchanged with 32. In the robot hand 2, a plurality of electrical contacts in the slip ring 35 are located in a plane perpendicular to the central axis J <b> 1 of the hand rotation shaft 322.

  A communication board 353 having a substantially annular plate shape is provided on the upper surface of the rotating part main body 321, and is connected to the disk substrate 351 of the slip ring 35 via wiring arranged inside the rotating part main body 321. The communication board 353 is also connected to a first connection board 38 provided on the lower surface of the rotating part main body 321 via wiring disposed inside the rotating part main body 321.

  As shown in FIG. 3, a plurality of electromagnetic valves 33 and 33 a are arranged on the outer surface of the rotating part main body 321 in an annular shape around the central axis J1. In the present embodiment, eight electromagnetic valves 33 are arranged at approximately equal intervals around the central axis J 1, and one electromagnetic valve 33 a is provided between the electromagnetic valves 33. The electromagnetic valves 33 and 33a are connected to a communication board 353 shown in FIG. 2 via wiring (not shown) arranged inside the rotating part main body 321. In FIG. 2, only two electromagnetic valves 33 are depicted.

  As shown in FIGS. 2 and 3, a substantially annular internal flow path 341 centering on the central axis J <b> 1 is formed inside the rotating portion main body 321, and the plurality of electromagnetic valves 33 and 33 a are respectively It is connected to the internal flow path 341 via internal flow paths 342 and 342a toward the central axis J1 inside the rotating part main body 321. The internal flow path 341 is connected to the internal flow path 340 formed inside the rotary unit main body 321 and the hand rotation shaft 322, and the internal flow path 340 is continuously connected to the inside of the arm rotation shaft 111 of the robot arm 11. Connected to the supply source. Note that the internal flow path 340 may be continued to an internal flow path formed inside the fixed portion 31 via a circumferential flow path formed on the outer surface of the hand rotation shaft 322. The internal flow path of the fixed part 31 may be connected to an air supply source via an internal flow path formed inside the robot arm 11, and an air supply connected to the outer surface of the fixed part 31 with a tube. It may be connected to a source.

  As shown in FIG. 3, the above-described coupling portion 323 is connected to the electromagnetic valve 33a via internal flow paths 344a and 344b. A signal for driving the electromagnetic valve 33a is sent from the control unit 12 (see FIG. 1) to the slip ring 35 via the internal wirings arranged inside the robot arm 11 and the fixed unit 31, respectively. It is sent from the fixed part 31 to the electromagnetic valve 33 a of the rotating part 32 via 35. Then, the electromagnetic valve 33a is controlled based on the signal. In the assembly robot 1, compressed air is supplied from the electromagnetic valve 33a to the coupling portion 323 via the internal flow path 344a, whereby a plurality of coupling balls protrude from the outer peripheral surface of the coupling portion 323, and the coupling hole 42 (FIG. 4). To the groove formed on the inner surface of the reference). Thereby, the hand tip portion 4 and the rotating portion 32 are coupled. Further, compressed air is supplied from the electromagnetic valve 33 a to the coupling portion 323 via the internal flow path 344 b, whereby a plurality of coupling balls are accommodated in the coupling portion 323. Thereby, the coupling | bonding of the hand front-end | tip part 4 and the rotation part 32 is cancelled | released.

  As described above, in the assembly robot 1, a signal (hereinafter referred to as “joining part control signal”) for switching between fixing and separating the hand tip 4 by the joining part 323 output from the control part 12 to the securing part 31. It is transmitted from the fixed portion 31 to the coupling portion 323 via the slip ring 35. The coupling part 323 is driven via a fluid in internal flow paths 340, 341, 342 a, 344 a, and 344 b (hereinafter referred to as “removable flow path”) formed inside the rotation part 32.

  4 and 5 are a side view and a bottom view of the hand tip portion 4, respectively. In the state where the hand tip portion 4 is attached to the hand main body portion 3, the center axis of the hand tip portion 4 and the center axis J1 of the hand main body portion 3 coincide with each other. The axis is also marked with J1. The hand tip portion 4 has a substantially columnar tip portion main body 41 centered on the central axis J <b> 1, and a plurality of gripping portions 5 are connected to the lower portion of the tip portion main body 41. As shown in FIG. 4, the above-described coupling hole 42 centering on the central axis J1 is formed at the center of the upper surface (upper surface in the figure) of the tip body 41, and the outer edge of the upper surface. In the vicinity, a second connection substrate 43 connected to the first connection substrate 38 (see FIG. 3) of the rotating portion main body 321 is provided.

  In the present embodiment, as shown in FIG. 5, four base blocks 50 are connected to the tip body 41, and two gripping portions 5 are provided in each base block 50. The two gripping portions 5 of each base block 50 include an internal flow path 411 formed inside the distal end portion main body 41 shown in FIG. 4 and an internal flow path 343 formed inside the rotating portion main body 321 (FIG. 3). And the corresponding solenoid valve 33 is connected. That is, the four solenoid valves 33 are connected to the four base blocks 50, and the other four solenoid valves 33 are not used.

  In the assembly robot 1, a signal for driving the electromagnetic valve 33 is sent from the control unit 12 (see FIG. 1) to the slip ring 35 via the internal wiring arranged in each of the robot arm 11 and the fixed unit 31. It is sent from the fixed portion 31 to the plurality of electromagnetic valves 33 of the rotating portion 32 via the slip ring 35. Then, the electromagnetic valve 33 is controlled based on the signal, and the internal flow paths 340, 341, 342, and 343 formed inside the rotating portion 32 and the internal flow formed inside the hand tip portion 4 are controlled. By supplying the compressed air through the path 411, the two grip portions 5 on the base block 50 are driven simultaneously. In other words, a signal (hereinafter referred to as a “gripping part control signal”) for controlling the gripping part 5 output from the control part 12 to the fixing part 31 is referred to as a gripping part 5 from the fixing part 31 via the slip ring 35. Is transmitted to. The grip portion 5 is driven via a fluid in the internal flow paths 340, 341, 342, 343, and 411 (hereinafter referred to as “grip flow paths”). When the two gripping portions 5 on one base block 50 are individually driven, one gripping portion 5 is connected to another internal flow path connected to the other electromagnetic valve 33 by a tube or the like. The

  6 and 7 are a front view and a side view, respectively, showing an enlarged view of the vicinity of one grip portion 5. In FIG. 6 and FIG. 7, in order to facilitate understanding of the drawings, the grip portion 5 is drawn with the tip directed downward. The grip portion 5 includes a grip portion main body 51 and two claw portions 52 arranged on the lower side of the grip portion main body 51. When the workpiece is gripped by the gripping portion 5, the two claw portions 52 move so as to approach each other in the left-right direction in FIG. 6 under the control of the electromagnetic valve 33 (see FIGS. 2 and 3). A work 91 is sandwiched between the claw portions 52. In FIG. 6, the work 91 and the claw part 52 in a state of gripping the work 91 are indicated by a two-dot chain line. When the gripping of the workpiece is released, the two claw portions 52 move so as to be separated from each other in the left-right direction in FIG. 6 under the control of the electromagnetic valve 33, and the two claw portions 52 are separated from the workpiece.

  As shown in FIGS. 6 and 7, a gripping state body 51 of each gripping unit 5 is attached with a gripping state acquisition unit 6 that acquires a gripping state of a workpiece by the gripping unit 5. The gripping state acquisition unit 6 is connected to the two claw parts 52 and is arranged so as to sandwich the two light shielding parts 61 and the two light shielding parts 61 that move together with the claw part 52, and the photocoupler 62. And a state acquisition board 63 for receiving a signal from the photocoupler 62.

  The state acquisition board 63 corresponding to each gripper 5 is connected to the second connection board 43 (see FIG. 4) via the wiring arranged inside the tip end body 41, and the control section 12 (see FIG. 4). 1) is supplied to the plurality of state acquisition boards 63 via the slip ring 35, the communication board 353, the first connection board 38 (see FIG. 2), and the second connection board 43. A signal output from the state acquisition board 63 (a signal indicating a gripping state of the workpiece, hereinafter referred to as a “grip state signal”) is transmitted through a wiring disposed inside the hand tip portion 4. It is sent to the second connection substrate 43 and sent to the rotating part 32 of the hand main body 3 via the second connection substrate 43 and the first connection substrate 38. Then, it is guided to the slip ring 35 via the wiring disposed inside the rotation unit 32 and the communication substrate 353, and transmitted from the rotation unit 32 to the fixed unit 31 via the slip ring 35. Further, it is sent to the control unit 12 via the fixed unit 31 and the wiring in the robot arm 11.

  FIG. A thru | or FIG. C is a view for explaining acquisition of a gripping state signal by the gripping state acquisition unit 6, and is a view of the vicinity of the gripping unit 5 as viewed from the tip side of the claw portion 52. FIG. A thru | or FIG. In C, in order to facilitate understanding of the drawing, only the upper end of the light shielding portion 61 is indicated by a solid line, and other portions are indicated by broken lines. FIG. As shown in A, in the state in which the two claw portions 52 are farthest in the left-right direction, one light-shielding portion 61 is located on the optical path from the LED 621 to the light-receiving element 622 of the photocoupler 62. Becomes OFF. Then, a gripping state signal (hereinafter referred to as “non-grip signal”) indicating a state in which the workpiece is not gripped is sent from the state acquisition substrate 63 to the control unit 12 (see FIG. 1). FIG. In A, the optical axis from the LED 621 of the photocoupler 62 to the light receiving element 622 is indicated by a one-dot chain line, and is denoted by reference numeral J2 (the same applies to FIGS. 8.B and 8.C).

  In the holding part 5, the two claw parts 52 move so as to approach each other, and FIG. As shown in B, when the workpiece 91 is sandwiched by the two claw portions 52, the two light shielding portions 61 overlap at a position slightly shifted from the optical axis J2, so the photocoupler 62 is turned on, A gripping state signal (hereinafter referred to as “grip signal”) indicating a state of gripping the workpiece 91 is sent from the state acquisition substrate 63 to the control unit 12. In the gripping state acquisition unit 6, the two claw portions 52 are shown in FIG. From the position shown in FIG. While moving to the position shown in B, a non-grip signal is continuously sent from the gripping state acquisition unit 6 to the control unit 12, and when the work 91 is held by the two claw portions 52, the gripping signal Are sent continuously. When the two claws 52 move away from each other and the workpiece 91 is released from gripping, a non-grip signal is continuously sent again. In the control unit 12, it is understood that the gripping unit 5 has shifted from the non-gripping state of the work 91 to the gripping state, has been in the gripping state for a predetermined time, and then has shifted to the non-gripping state again. It is determined that the gripping and releasing are performed normally.

  On the other hand, when the gripper 5 fails to grip the workpiece, the two claw portions 52 are shown in FIG. From the position shown in FIG. 8 through the position shown in FIG. Move to the position shown in C. FIG. As shown in C, in the state where the distance in the left-right direction between the two claw portions 52 is smaller than the width of the work 91 (see FIG. 8.B), the other light shielding portion 61 (that is, FIG. 8. Since the light shielding portion 61) different from that located on the optical axis J2 is located at A, the photocoupler 62 is turned off. The claw 52 is shown in FIG. From the position shown in FIG. While moving to the position indicated by C, a non-gripping signal is continuously sent from the state acquisition substrate 63 to the control unit 12. Precisely, the claw 52 is shown in FIG. Only during a very short time passing the position shown in B, a grip signal is sent from the state acquisition board 63 to the control unit 12, but the grip signal is ignored because its duration is shorter than a predetermined threshold. The control unit 12 determines that the workpiece 91 has not been gripped normally.

  As described above, in the assembly robot 1, the gripping unit control signal and the coupling unit control signal output from the control unit 12 to the fixing unit 31 are transmitted from the fixing unit 31 to the rotating unit 32 via the slip ring 35. The grip state signal transmitted and output from the grip state acquisition unit 6 is transmitted from the rotating unit 32 to the fixing unit 31 via the slip ring 35 and sent to the control unit 12. For this reason, in the hand main body portion 3 of the robot hand 2, it is possible to suppress (or prevent) the signal transmission wiring between the fixed portion 31 and the rotating portion 32 from being exposed to the outside. 2 or the movement range of the robot arm 11 can be suppressed (or prevented). Further, the disconnection of the wiring between the fixed portion 31 and the rotating portion 32 can be prevented, and the productivity of the assembly robot 1 can be prevented from being lowered.

  Furthermore, in the robot hand 2, the hand tip portion 4 including the grip portion 5 and the grip state acquisition portion 6 is detachably fixed to the rotating portion 32, so when changing the type of the grip portion 5, etc. By replacing the hand tip 4 with another hand tip 4, the grip 5 can be easily replaced. Moreover, since it is not necessary to replace the hand main body 3 provided with the slip ring 35, the electromagnetic valve 33, etc., the manufacturing cost of the robot hand 2 can also be reduced.

  In the robot hand 2, the plurality of electrical contacts in the slip ring 35 are positioned in a plane perpendicular to the central axis J 1 of the hand rotation shaft 322, thereby shortening the length of the slip ring 35 in the central axis J 1 direction. The robot hand 2 can be reduced in size.

  The gripping part 5 is driven via compressed air that is a fluid in a gripping channel formed inside the rotating part 32 and the hand tip part 4. In this way, by restricting the piping of the fluid for driving the grip portion 5 from being exposed to the outside of the robot hand 2, it is possible to relax restrictions on the movable range of the robot hand 2 and the robot arm 11 due to the piping. it can. Further, the increase in size of the robot hand 2 and the assembly robot 1 can be suppressed. Further, the coupling portion 323 is driven via compressed air that is a fluid in the attachment / detachment flow path formed inside the rotation portion 32. As described above, by preventing the fluid piping for driving the coupling portion 323 from being exposed to the outside of the robot hand 2, the restriction of the movable range of the robot hand 2 and the robot arm 11 by the piping is further relaxed. be able to. Moreover, the enlargement of the robot hand 2 and the assembly robot 1 can be further suppressed.

  In the robot hand 2, wiring for guiding the grip state signal output from the grip state acquisition unit 6 to the slip ring 35 is disposed inside the hand tip portion 4 and the rotation unit 32. For this reason, it is possible to suppress (or prevent) the movement range of the robot hand 2 and the robot arm 11 from being limited by the wiring, and to prevent the wiring from being disconnected to prevent the assembly robot 1 from being lowered in productivity. be able to. In addition, it is possible to suppress the wiring and the like from being exposed to the outside of the robot hand 2 and to prevent the robot hand 2 and the assembly robot 1 from being enlarged.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  For example, if the length of the robot hand 2 in the direction of the central axis J1 is within an allowable range, the slip ring 35 is in contact with the drum substrate having a cylindrical surface around the central axis J1 and the drum substrate. A drum-type slip ring including a child may be used. Further, as a fluid for driving the grip portion 5 and the coupling portion 323, a fluid other than compressed air such as a gas or driving oil may be used.

  The gripping part 5 is not limited to a structure in which the work is gripped by the two claw parts 52, and may be one that grips the work by the four claw parts, or a part that adsorbs the work. The hand tip 4 may be provided with only one grip 5. In the gripping state acquisition unit 6, a magnet type sensor, a vacuum switch, or the like may be used for detecting the gripping state of the workpiece by the gripping unit 5 instead of the light shielding unit 61 and the photocoupler 62. In the assembly robot 1, the arm rotation shaft 111 may be inserted into the fixed portion 31 of the hand main body portion 3. Further, the robot hand 2 may be manufactured as an integral part of the robot arm 11, and in this case, the fixing unit 31 may be regarded as a part of the robot arm 11.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

2 robot hand 4 hand tip 5 gripping part 6 gripping state acquisition part 12 control part 31 fixing part 32 rotating part 35 slip ring 91 work 322 hand rotating shaft 323 coupling part 340 to 343, 342a, 344a, 344b, 411 internal flow path

Claims (5)

A robot hand provided at the tip of the robot arm of the assembly robot,
A fixed part into which the rotating shaft is inserted;
A rotating part that is adjacent to the fixed part and rotates about the rotation axis;
A tip part detachably attached to the rotating part;
A slip ring disposed between the fixed part and the rotating part for transmitting an electrical signal;
With
The tip is
A gripping part for gripping the workpiece;
A gripping state acquisition unit that acquires a gripping state of a workpiece by the gripping unit;
With
The rotating part includes an attaching / detaching mechanism for detachably fixing the tip part,
A signal for controlling the gripping part outputted from the control part to the fixing part, and a signal for switching the fixing and separation of the tip part by the attachment / detachment mechanism are respectively received from the fixing part via the slip ring. Transmitted to the part and the attaching / detaching mechanism,
A robot hand, wherein a signal output from the gripping state acquisition unit is transmitted from the rotating unit to the fixed unit via the slip ring and sent to the control unit. The robot hand according to claim 1,
The robot hand according to claim 1, wherein an electrical contact in the slip ring is located in a plane perpendicular to the rotation axis. The robot hand according to claim 1 or 2,
The robot hand, wherein the gripping part is driven via a fluid in a gripping channel formed inside the rotating part and the tip part. The robot hand according to any one of claims 1 to 3,
The robot hand, wherein the attaching / detaching mechanism is driven via a fluid in an attaching / detaching channel formed inside the rotating unit. The robot hand according to any one of claims 1 to 4,
A robot hand characterized in that wiring for guiding a signal output from the gripping state acquisition unit to the slip ring is disposed inside the tip portion and the rotating portion.

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