Drive unit and robot
Patent Information
- Application Number
- JP2021157610
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-09-28
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2041-09-28
Smart Images

Figure 0007643276000001 
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Abstract
Description
[Technical field]
[0001] The present invention relates to a drive unit and a robot. [Background technology]
[0002] Conventionally, a plurality of drive units equipped with reduction gears are used in articulated robots, etc. Patent Document 1 discloses that the actuator with built-in reduction mechanism (corresponding to the drive unit) of the articulated robot has signal lines and power lines connected to the hand at the tip end of the articulated robot and the actuator with built-in reduction mechanism at the tip end, etc., routed through a hollow portion formed in the output shaft of each actuator with built-in reduction mechanism. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2011-2062 A Summary of the Invention [Problem to be solved by the invention]
[0004] However, in Patent Document 1, when assembling a multi-joint robot using an actuator with a built-in reduction mechanism or when replacing an actuator with a built-in reduction mechanism of a multi-joint robot, the signal lines and power lines are wired through the hollow portion, so the signal lines and power lines need to be pulled in and out of the hollow portion of each actuator with a built-in reduction mechanism, making the assembly and replacement work cumbersome. [Means for solving the problem]
[0005] The drive unit includes a motor having a rotating shaft with a through hole, a drive part that rotates the rotating shaft, and a case that covers at least a portion of the drive part, a reducer having an input part that engages with one end of the rotating shaft, an attachment part that is attached to the motor, and an output part that reduces the rotation of the rotating shaft and outputs it, a first connector fixed to the case of the motor and connected to a first wiring that connects to the outside, a second connector fixed to the attachment part of the reducer and connected to a second wiring that connects to the outside, and internal wiring that passes through the through hole and connects to the first connector and the second connector.
[0006] The robot includes the drive unit described above, a first member having a first housing and through which the first wiring passes, and a second member having a second housing and through which the second wiring passes and which rotates relative to the first member, and the motor is fixed to the first member, and the output section is fixed to the second member. [Brief description of the drawings]
[0007] [Figure 1] 1 is a side view showing a schematic configuration of a robot according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing a schematic configuration of a drive unit. [Diagram 3] FIG. 2 is a cross-sectional view showing a schematic configuration of a drive unit. [Figure 4] FIG. 11 is a cross-sectional view showing a schematic configuration of a drive unit according to a second embodiment. [Diagram 5] FIG. 2 is a cross-sectional view showing a schematic configuration of a drive unit. [Figure 6] FIG. 11 is a partial cross-sectional view showing a schematic configuration of a drive unit according to a third embodiment. [Figure 7] FIG. 13 is a partial cross-sectional view showing a schematic configuration of a drive unit according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] Hereinafter, an embodiment will be described with reference to the drawings. Note that, for the sake of convenience, the dimensions of each component in each drawing are appropriately exaggerated as necessary, and the dimensional ratios between the components do not necessarily coincide with the actual dimensional ratios.
[0009] 1. First embodiment The configuration of the robot 1 according to this embodiment will be described. Fig. 1 is a side view showing a schematic configuration of a robot 1 according to this embodiment. The robot 1 shown in Fig. 1 is a SCARA (Selective Compliance Assembly Robot Arm) robot (horizontally articulated robot).
[0010] The robot 1 can perform operations such as supplying, removing, transporting, and assembling precision equipment and the parts that constitute the equipment. In the following description, an XYZ coordinate system is set, and the positional relationship of each member is described with reference to this XYZ coordinate system. In this case, the vertical direction is defined as the Z-axis direction, the horizontal direction and the length direction of the base 10 is defined as the Y-axis direction, and the horizontal direction and the width direction of the base 10 is defined as the X-axis direction. In addition, the direction of gravity in the Z-axis direction is referred to as the downward direction or lower side, and the direction opposite to the direction of gravity is referred to as the upward direction or upper side.
[0011] The robot 1 includes a base 10, a first arm 11, and a first drive unit 2. The base 10 is a part for mounting the robot 1 to an arbitrary installation location. The base 10 is fixed to, for example, a floor surface (not shown) by bolts or the like. The installation location of the base 10 is not particularly limited, and examples thereof include a floor, a wall, a ceiling, and a movable dolly.
[0012] The first arm 11 is connected to an upper end of the base 10 via a first drive unit 2 mounted on the base 10. The first arm 11 is rotatable around a first axis J1 along a vertical direction (Z-axis direction) relative to the base 10. Note that in this embodiment, rotation refers to clockwise and counterclockwise rotation with respect to a central axis as shown in FIG.
[0013] The robot 1 also includes a second arm 12 and a second drive unit 3. The second arm 12 is connected to the tip of the first arm 11 via the second drive unit 3 mounted on the second arm 12. The second arm 12 is rotatable around a second axis J2 that is aligned in the vertical direction (Z-axis direction) relative to the first arm 11.
[0014] A working head 13 is disposed at the tip of the second arm 12. The working head 13 includes a spline nut 14 and a ball screw nut 15 that are coaxially disposed at the tip of the second arm 12, and a spline shaft 16 that is inserted through the spline nut 14 and the ball screw nut 15. The spline shaft 16 is rotatable about a third axis J3 that is aligned in the vertical direction (Z-axis direction) relative to the second arm 12, and is also movable (raised and lowered) in the up and down direction.
[0015] An end effector (not shown) is connected to a lower tip 17 of the spline shaft 16. The end effector is not particularly limited, and examples thereof include an end effector that grips a transported object and an end effector that processes a workpiece.
[0016] Of the multiple power system wirings (hereinafter referred to as power lines) connected to each electronic component (e.g., second drive unit 3, etc.) arranged in second arm 12, in this embodiment, wirings other than the power lines that drive the drive section described below and the transmission / reception component 50 (FIGS. 1 and 2) are guided into the base 10 through a tubular wiring routing section 18 that connects second arm 12 and base 10. The multiple power system wirings are then gathered together within the base 10, and are routed to a control device 19 installed in the base together with the wiring connected to the first drive unit 2. The control device 19 provides overall control of the robot 1.
[0017] In this embodiment, signal wiring (hereinafter referred to as signal lines) that communicates bidirectionally via the first drive unit 2 and the second drive unit 3 is routed to the control device 19 in the same manner as the power lines. In this embodiment, the signal lines are implemented using optical fibers. Optical communication will be described later. The drive of the first drive unit 2 and the second drive unit 3 is controlled by this control device 19.
[0018] In such a robot 1, the first drive unit 2 transmits a drive force for rotating the first arm 11 relative to the base 10 from the base 10 side to the first arm 11 side. Also, the second drive unit 3 transmits a drive force for rotating the second arm 12 relative to the first arm 11 from the second arm 12 side to the first arm 11 side.
[0019] The drive unit will now be described. The first drive unit 2 and the second drive unit 3 as drive units have the same configuration, so in the following, only the first drive unit 2 will be described.
[0020] 2 and 3 are cross-sectional views showing a schematic configuration of a drive unit (first drive unit 2) according to this embodiment. Note that Fig. 2 and Fig. 3 show a cross section passing through the first axis J1 and parallel to the XZ plane. Fig. 2 is a diagram in which reference numerals are mainly added to the motor 20, the reducer 30, the base 10, and the first arm 11 of the first drive unit 2, and Fig. 3 is a diagram in which reference numerals are mainly added to the transmission / reception configuration part 50 of the first drive unit 2.
[0021] The first drive unit 2 generally includes a motor 20, a reducer 30, a support member 40, and a transmitting / receiving component 50.
[0022] The support member 40 has a motor support part 41 which is a part that supports the motor 20, a reducer support part 43 which is a part that supports the reducer 30, and in this embodiment, a mounting plate 45 which is a part that mounts the motor 20 of the first drive unit 2 to the base housing 101 of the base 10. The motor support part 41 and the reducer support part 43 are integrally configured as a single part. The mounting plate 45 is configured as a separate part from the motor support part 41 and the reducer support part 43 which are integrally configured.
[0023] The motor support part 41 is formed in a generally cylindrical shape centered on a central axis A of rotation of a rotating shaft 22 of the motor 20 described later. The reducer support part 43 is formed to protrude like a flange radially outward from the motor support part 41. Furthermore, the reducer support part 43 has insertion holes 431 formed at predetermined intervals along the outer periphery for fixing a mounting plate 45 of the support member 40 and a mounting part 351 of a rigid gear 35 described later to the reducer support part 43.
[0024] The mounting plate 45 is formed in an annular shape centered on the central axis A, and includes a support portion 451 in an inner region for fixing the reducer 30 together with the reducer support portion 43 of the support member 40, and an attachment portion 453 in an outer region for fixing the motor 20 to the base 10 as the first member. In addition, in the support portion 451 of the mounting plate 45, in this embodiment, insertion holes 452 for fixing the mounting plate 45 and the attachment portion 351 of the rigid gear 35 to the reducer support portion 43 of the support member 40 are formed corresponding to the insertion holes 431 of the reducer support portion 43. In addition, in the mounting portion 453 of the mounting plate 45, in this embodiment, insertion holes 454 for fixing the motor 20 of the first drive unit 2 to the base housing 101 constituting the base 10 are formed at predetermined intervals along the outer periphery.
[0025] The configuration and operation of the motor 20 will now be described. The motor 20 is a so-called servo motor. Specifically, an AC servo motor is used. The motor 20 may be, for example, a DC servo motor. As shown in FIG. 2, the motor 20 includes a rotor 21, a stator 23, a first case 24, a second case 25, a third case 26, an optical encoder 28 as a rotation detector, and an encoder board 29 as a rotation detection board. The motor 20 also includes bearings 271 and 272.
[0026] In this embodiment, an encoder 28 is used as a rotation detector, but this is not limited to this. For example, a resolver that outputs the rotation angle as a two-phase AC voltage (analog signal), or a Hall sensor that detects a magnetic field and outputs an analog signal proportional to its magnitude can be used.
[0027] The first case 24, the second case 25, the third case 26, and the motor support portion 41 of the support member 40 also function as a case that surrounds the motor 20.
[0028] 2, bearings 271, 272 are installed in the center of the motor support part 41 and the second case 25. In this embodiment, the central axis A of rotation of the rotating shaft 22 constituting the rotor 21 is the same as the first axis J1 which is the center of rotation of the first arm 11.
[0029] The bearings 271 and 272 are rolling bearings including an inner ring and an outer ring. Both ends of the rotating shaft 22 are fixed to the inner rings of the bearings 271 and 272 by interference fit. The outer ring of one bearing 271 is supported by the motor support portion 41 of the support member 40. The outer ring of the other bearing 272 is supported by the second case 25. The first case 24, the second case 25, and the third case 26 are fixed to the motor support portion 41.
[0030] The rotating shaft 22 of the motor 20 is supported by the motor support part 41 and the second case 25 via bearings 271 and 272, and rotates around the central axis A. The rotating shaft 22 is connected to the reduction gear 30 at the end on the bearing 271 side, and transmits driving force to the reduction gear 30. In addition, an encoder 28 serving as a rotation detector that detects rotation of the rotating shaft 22 is installed on the outer circumferential surface of the rotating shaft 22 at the end on the bearing 272 side of the rotating shaft 22. Therefore, the encoder 28 rotates in accordance with the rotation of the rotating shaft 22.
[0031] An encoder board 29 serving as a rotation detection board for receiving a signal from the encoder 28 is fixed to the board support part 261 so as to surround the outer circumferential surface of the rotating shaft 22 at an end lower than the portion of the rotating shaft 22 where the encoder 28 is attached. The encoder 28 and the encoder board 29 are enclosed in the third case 26.
[0032] The rotor 21 includes a rotating shaft 22 and a magnet 211. The rotating shaft 22 is formed in a cylindrical shape with a reduced diameter along the direction of the central axis A. The rotating shaft 22 is also formed with a hollow through hole 221 that is formed along the direction of the central axis A. The rotating shaft 22 is made of a soft magnetic material such as iron.
[0033] The magnet 211 is fixed to the outer peripheral surface of the rotating shaft 22 along the central axis A. The magnet 211 is formed in an annular shape, and a plurality of magnets are arranged in the circumferential direction, and has a multi-pole structure in which a plurality of magnetic poles are formed. The magnet 211 is composed of, for example, six magnet pieces, and is configured so that the polarities are NSNSNS in the circumferential direction. The magnet 211 is surrounded by the stator 23.
[0034] Stator 23 surrounds rotor 21 (rotating shaft 22, magnets 211) around central axis A. Stator 23 is formed in a cylindrical shape, arranged at predetermined intervals in the circumferential direction, and each includes coil 232 around iron core 231 which serves as a core.
[0035] When AC current is applied to stator 23 of motor 20 configured as above, stator 23 becomes an electromagnet, and since the direction and magnitude of the AC current alternate, stator 23 switches between an N pole and an S pole. Accordingly, magnet 211 of rotor 21 is attracted or repelled, causing rotor 21 (rotating shaft 22) to rotate.
[0036] Stator 23 (iron core 231, coil 232) functions as a drive unit that rotates rotating shaft 22. First case 24 surrounds at least a portion of rotor 21 and stator 23, that is, covers at least a portion of the drive unit.
[0037] The configuration and operation of the reducer 30 will be described. The reducer 30 is a reducer that uses a wave gear mechanism commonly known as a wave gear reducer. The reducer 30 reduces the rotation of the driving force input from the rotating shaft 22 of the motor 20 and outputs it. Then, at the output side of the reducer 30, a torque proportional to the reduction ratio can be obtained.
[0038] 2, the reducer 30 includes a wave generator 31, a flexible gear 33 as a flexible external gear, and a rigid gear 35 composed of an internal gear. In this embodiment, the wave generator 31 serves as an input part that engages with one end of the rotating shaft 22. In this embodiment, the flexible gear 33 serves as an output part that reduces the speed of rotation of the rotating shaft 22 and outputs it. In this embodiment, the rigid gear 35 serves as an attachment part that is attached to the motor 20.
[0039] In this embodiment, the rigid gear 35 functions as the attachment portion, and the flexible gear 33 functions as the output portion. However, this is not limited to this, and the flexible gear 33 may function as the attachment portion, and the rigid gear 35 may function as the output portion.
[0040] The rigid gear 35 is a gear made of a rigid body that does not substantially bend in the radial direction of the central axis A, and is an annular internal gear having internal teeth 352. In this embodiment, the rigid gear 35 is a spur gear. That is, the internal teeth 352 have teeth that are parallel to the central axis A. The teeth of the internal teeth 352 may be inclined with respect to the central axis A. That is, the rigid gear 35 may be a helical gear or a herringbone gear.
[0041] The rigid gear 35 is composed of two parts: a mounting part 351 that mounts the rigid gear 35 to the reducer support part 43 of the support member 40, and a connecting part 354 that connects it to the arm of the robot 1 (in Figure 1, the first arm 11).
[0042] The mounting portion 351 is formed with the above-mentioned internal teeth 352 at a lower end portion radially inward of the central axis A. The mounting portion 351 is formed with a mounting screw hole 353 for mounting to the reducer support portion 43 of the support member 40 via the support portion 451 of the mounting plate 45. The mounting screw hole 353 is formed opposite the insertion holes 431, 452. In this embodiment, the connecting portion 354 is formed with a fixing screw hole 355 for connecting to the first arm 11.
[0043] The mounting portion 351 and the connecting portion 354 are connected by a bearing 356, and the connecting portion 354 is configured to be rotatable relative to the mounting portion 351. The bearing 356 is a so-called cross roller bearing, in which rollers are arranged alternately at angles of +45° and -45° with respect to the rotation axis, and which is a bearing capable of receiving both radial and thrust loads.
[0044] The flexible gear 33 is inserted inside the rigid gear 35. The flexible gear 33 is a gear having a flexible cylindrical portion 331 that is flexible and deformable in the radial direction of the central axis A. The flexible gear 33 is also an external gear having external teeth 332 that mesh with internal teeth 352 of the rigid gear 35. The number of teeth of the flexible gear 33 is smaller than the number of teeth of the rigid gear 35.
[0045] The flexible gear 33 is configured in a top hat shape including a cylindrical portion 331 and a flange portion 333 extending from an upper end of the cylindrical portion 331 radially outward of the central axis A. The external teeth 332 are formed at a lower end of the cylindrical portion 331 radially outward of the central axis A. The flexible gear 33 has insertion holes 334 formed at predetermined intervals along the outer periphery of the flange portion 333 for fixing the reducer 30 to the first arm 11 and for fixing the reducer 30 to a connecting portion 354 of the rigid gear 35. The insertion holes 334 are formed opposite the fixing screw holes 355.
[0046] The wave generator 31 includes a wave generating unit 311 and a fixing unit 318. The fixing unit 318 is formed of, for example, a screw or a bolt, and fixes the wave generating unit 311 and the rotating shaft 22 of the motor 20 in the radial direction of the central axis A.
[0047] The wave generating unit 311 includes a main body 312 and a bearing 313 attached to the outer periphery of the main body 312. When viewed from the direction of the central axis A, the outer periphery of the main body 312 is formed in an elliptical or oval shape.
[0048] The bearing 313 is a rolling bearing including flexible inner and outer rings 315 and 316, and a number of balls 317 disposed between them. The inner ring 315 is fitted around the outer periphery of the main body 312, and is elastically deformed into an elliptical or oblong shape along the outer periphery of the main body 312. Accordingly, the outer ring 316 is also elastically deformed into an elliptical or oblong shape. The outer periphery of the inner ring 315 and the inner periphery of the outer ring 316 each serve as a raceway surface that guides and rolls the balls 317 in the circumferential direction. The balls 317 are held by a cage (not shown) so as to keep the distance between them constant in the circumferential direction.
[0049] With the above configuration, the wave generator 31 is located inside the flexible gear 33 and is rotatable around the central axis A. The wave generator 311 contacts the inner peripheral surface of the cylindrical portion 331 of the flexible gear 33 and bends the cylindrical portion 331 into an elliptical or oblong shape with a major axis and a minor axis, thereby partially meshing the external teeth 332 with the internal teeth 352 of the rigid gear 35. Here, the flexible gear 33 and the rigid gear 35 are meshed with each other internally and externally so as to be rotatable around the central axis A.
[0050] In this speed reducer 30, when the driving force from the motor 20 described above is input to the wave generator 31, the flexible gear 33 and the rigid gear 35 rotate relatively around the central axis A due to the difference in the number of teeth while moving their meshing positions in the circumferential direction. As a result, the rotation of the driving force input to the wave generator 31 from the rotating shaft 22 of the motor 20, which is the driving source, is reduced in speed and output from the flexible gear 33. Then, on the output side, a torque proportional to the reduction ratio can be obtained. In other words, a speed reducer 30 can be realized in which the wave generator 31 is on the input side and the flexible gear 33 is on the output side.
[0051] In this embodiment, the mounting portion 351 of the rigid gear 35 that meshes with the flexible gear 33 is fixed to the support member 40, so that the flexible gear 33 rotates together with the connecting portion 354 of the rigid gear 35. Therefore, in this embodiment, when the driving force from the motor 20 is input to the wave generator 31 and the wave generator 31 rotates, the flexible gear 33 moves the meshing position with the rigid gear 35 (mounting portion 351) in the circumferential direction and rotates relatively around the central axis A due to the difference in the number of teeth. Note that the rotation direction of the wave generator 31 and the rotation direction of the flexible gear 33 are opposite to each other.
[0052] An example of a method for assembling the first drive unit 2 in this embodiment will be briefly described. Note that a description of the assembly of the motor 20 is omitted. Also, the assembly order is not limited to the order described below.
[0053] First, the motor 20 is assembled to the support member 40 (motor support portion 41). At this time, the first case 24 of the motor 20 abuts against the motor support portion 41. Also, the outer ring of the bearing 271, the inner ring of which is fixed to the rotating shaft 22 of the motor 20 in advance by interference fit, is supported by the inner circumferential surface of the motor support portion 41.
[0054] Next, in the support member 40, the mounting plate 45, which is a separate body, is placed above the reducer support part 43. In this case, the positions are adjusted so that the insertion hole 431 formed in the reducer support part 43 and the insertion hole 452 formed in the support part 451 of the mounting plate 45 overlap with each other.
[0055] Next, the main body 312 of the wave generator 31 of the reducer 30 and the rotating shaft 22 of the motor 20 are fixed to each other by the fixing part 318 in the radial direction of the central axis A. The fixing method is not particularly limited, and may be, in addition to fixing by screws or bolts, fixing by adhesive, welding, or the like.
[0056] Next, as a sub-assembly, the flexible gear 33 is assembled to the rigid gear 35. In detail, the cylindrical portion 331 of the flexible gear 33 is inserted from above along the inner peripheral surface of the mounting portion 351 of the rigid gear 35. Then, the flange portion 333 of the flexible gear 33 is brought into contact with the upper surface of the connecting portion 354. As a result, the external teeth 332 of the flexible gear 33 and the internal teeth 352 of the rigid gear 35 face each other in cross section.
[0057] Next, the sub-assembled rigid gear 35 and flexible gear 33 are engaged from above with the outer circumferential surface of the wave generator 31. As a result, the cylindrical portion 331 of the flexible gear 33 elastically deforms along the outer circumferential surface of the wave generator 31 (the outer circumferential surface of the outer ring 316 of the bearing 313) and engages with it, so that the external teeth 332 of the flexible gear 33 and the internal teeth 352 of the rigid gear 35 partially mesh with each other. In this case, the positions of the mounting screw holes 353 formed in the mounting portion 351 of the rigid gear 35 and the insertion holes 452 of the mounting plate 45 are adjusted so that they overlap with each other.
[0058] Next, the bolt B1 is inserted from below the reducer support part 43 through the insertion hole 431 of the reducer support part 43 and the insertion hole 452 of the mounting plate 45, and screwed into the mounting screw hole 353 of the rigid gear 35. In this way, the mounting part 351 of the rigid gear 35 is attached to the support member 40, including the mounting plate 45. Through this assembly, the motor 20 and the reducer 30 are fixed in place.
[0059] By the above assembly, the motor 20 and the reducer 30 are fixed, and the transmission / reception component 50 described later is installed, more specifically, the internal wiring 58 is installed in the through hole 221, and the first connector 51 and the second connector 55 are installed, completing the assembly of the first drive unit 2. In this state, the internal wiring 58 is connected to the first connector 51 and the second connector 55. In this state, the first wiring 53 (first connector portion 531) is not connected to the first connector 51 described later, and the second wiring 57 (second connector portion 571) is not connected to the second connector 55 described later.
[0060] The assembly of the first drive unit 2 to the robot 1 will now be described. In this embodiment, the first drive unit 2 is a drive unit that rotates a first arm 11, which serves as a second member, relatively to a base 10, which serves as a first member.
[0061] In this embodiment, the first drive unit 2 fixes the motor 20 to the base 10 as a first member. In detail, in the first drive unit 2, the mounting plate 45 of the support member 40 is fixed to a base housing 101 as a first housing constituting the base 10.
[0062] The base housing 101 has a shape (for example, a step portion 102) that matches the outer diameter of the mounting plate 45, and a fixing screw hole 103 is formed opposite the insertion hole 454. The support member 40 is fixed to the base 10 by positioning the support member 40 (mounting plate 45) on the step portion 102 from above the base housing 101, and then inserting a bolt B2 from above into the insertion hole 454 and screwing it into the fixing screw hole 103. As a result, the first wiring 53 is routed inside the base 10 as the first member.
[0063] In the present embodiment, the first driving unit 2 fixes the flexible gear 33 as an output section to the first arm 11 as a second member. In detail, in the first driving unit 2, the flexible gear 33 of the reducer 30 is fixed to a first arm housing 111 as a second housing constituting the first arm 11.
[0064] The first arm housing 111 has an opening 112 described later and a shape (for example, a stepped portion 113) that matches the outer diameter of the flexible gear 33, and an insertion hole 114 is formed opposite the insertion hole 334. The flexible gear 33 is fixed to the first arm 11 by positioning the flexible gear 33 (flange portion 333) at the stepped portion 113 from below the first arm housing 111, and then inserting a bolt B3 from above through the insertion holes 114, 334 and screwing it into the fixing screw hole 355. As a result, the second wiring 57 is routed inside the first arm 11 as the second member.
[0065] With the above assembly, in this embodiment, the driving force generated by the rotation of the motor 20 fixed to the base 10, which is fixed to a floor surface or the like, is input to the wave generator 31 from the base 10, and when the wave generator 31 rotates, the first arm 11 fixed to the flexible gear 33 rotates around the central axis A (first axis J1) relative to the base 10.
[0066] The configuration and operation of the transmission / reception configuration unit 50 will now be described. The transmission / reception component 50 is a part that constitutes the first drive unit 2, and is a part that routes signal lines and power lines.
[0067] As an operation of the transmission / reception component 50, for example, when detecting the number of rotations of the motor 20 in the first drive unit 2, a signal instructing detection of the number of rotations from the control device 19 is received by optical communication, and data on the number of rotations of the motor 20 detected by the first drive unit 2 is transmitted to the control device 19 by optical communication. This allows the control device 19 to appropriately control and operate the rotation angle of the first arm 11. Furthermore, in this embodiment, transmission and reception between the control device 19 and the second drive unit 3 installed on the second arm 12 is also performed via the transmission and reception component 50 of the first drive unit 2.
[0068] 1 includes a hand (not shown) for grasping an object as an end effector, and when a signal from a force sensor such as a tactile sensor for measuring a grasping force provided on the hand is transmitted to the control device 19, the transmission is performed via the second drive unit 3 and the first drive unit 2. When a camera is provided on the spline shaft 16 shown in FIG. 1, an image signal captured by the camera is also transmitted to the control device 19 via the second drive unit 3 and the first drive unit 2. When the number of signal lines is increased, the wavelength of light may be changed to perform communication for the required number of lines.
[0069] As an operation of the transmission / reception component 50, for example, when driving the motor 20 in the first drive unit 2, the driving power (e.g., AC current) from the control device 19 is transmitted to the first connector 51 via the first wiring 53 (first power line 533), and the driving power is supplied to the stator 23 (coil 232) to rotate the motor 20.
[0070] Furthermore, for example, when driving the motor 20 in the second driving unit 3, driving power (e.g., AC current) from the control device 19 is transmitted to the second connector 55 of the second driving unit 3 via the first driving unit 2. Then, after being transmitted to the first connector 51 via the internal wiring 58 (power line 582) of the second driving unit 3, the driving power is supplied to the stator 23 (coil 232) to rotate the motor 20.
[0071] The transmission / reception component 50 is configured to include a first connector 51, a first wiring 53, a second connector 55, a second wiring 57, and an internal wiring 58.
[0072] The transmission / reception component 50 is configured so that internal wiring 58 is installed in a hollow through-hole 221 provided in the rotating shaft 22, enabling communication of signals and power. The internal wiring 58 has a signal line 581 and a power line 582. In this embodiment, the signal line 581 is made of optical fiber. The power line 582 is made of an ordinary conductor.
[0073] Moreover, the signal line 581 and the power line 582 are aligned in the length direction and configured in a fixed state. In this embodiment, the internal wiring 58 is connected at both ends to the first connector 51 and the second connector 55. The internal wiring 58 installed in the through hole 221 of the rotating shaft 22 is in a fixed state without being moved by the rotation of the rotating shaft 22.
[0074] 3, the first connector 51 is configured to have a first transmitting / receiving circuit board 511, a signal line terminal 512 and a power line terminal 513 on the internal wiring 58 side, and a signal line terminal 514 and a power line terminal 515 on the first wiring 53 side. The first connector 51 is fixed to the lower surface side of the third case 26 of the motor 20, on the side of the lower end 22a of the rotating shaft 22.
[0075] The first connector 51 has a signal line terminal 512 on the internal wiring 58 side and is connected to a signal line 581 of the internal wiring 58. The first connector 51 also has a power line terminal 513 on the internal wiring 58 side and is connected to a power line 582 of the internal wiring 58.
[0076] The first connector 51 is connected to a first wiring 53 that is connected to the outside. Here, the "outside" corresponds to the control device 19 in this embodiment.
[0077] The first transmission / reception circuit board 511 is connected to the encoder board 29 and transmits / receives electric signals to / from the encoder board 29. The encoder board 29 in this embodiment is configured separately from the first transmission / reception circuit board 511 (first connector 51). The first transmission / reception circuit board 511 is also connected to the stator 23 serving as a drive unit and supplies power to the stator 23 (coil 232).
[0078] The signal line terminal 512 on the internal wiring 58 side of the first connector 51 includes a light emitting element and a light receiving element (both not shown) that are connected to a lower end that is one end of the signal line 581 of the internal wiring 58 via the first transmitting / receiving circuit board 511. The power line terminal 513 on the internal wiring 58 side of the first connector 51 includes a connect portion (not shown) that is connected to a lower end that is one end of the power line 582 of the internal wiring 58 via the first transmitting / receiving circuit board 511.
[0079] When the first connector 51 (first transmission / reception circuit board 511) is fixed to the lower surface side of the third case 26, one end of the signal line 581 of the internal wiring 58 and the signal line terminal 512 on the internal wiring 58 side are connected so as to be capable of optical communication. Also, when the first connector 51 (first transmission / reception circuit board 511) is fixed to the lower surface side of the third case 26, one end of the power line 582 of the internal wiring 58 and the power line terminal 513 on the internal wiring 58 side are connected so as to be conductive.
[0080] The signal line terminal 514 on the first wiring 53 side of the first connector 51 includes a light emitting element and a light receiving element (both not shown) that are connected to an end of the first signal line 532 of the first wiring 53 via the first transmitting / receiving circuit board 511. The power line terminal 515 on the first wiring 53 side of the first connector 51 includes a connect portion (not shown) that is connected to an end of the first power line 533 of the first wiring 53 via the first transmitting / receiving circuit board 511.
[0081] The first wiring 53 has a first signal line 532 and a first power line 533. The first wiring 53 is connected to the control device 19. The first signal line 532 is made of optical fiber, similar to the signal line 581 of the internal wiring 58. The first power line 533 is made of a conductor, similar to the power line 582 of the internal wiring 58.
[0082] An end of the first signal line 532 and the first power line 533 of the first wiring 53 is configured as a first connecting portion 531. The first wiring 53 is detachable from the first connector 51 (first transmitting / receiving circuit board 511) by the first connecting portion 531.
[0083] When the first wiring 53 is attached to the first connector 51, an end of the first signal line 532 and a signal line terminal 514 on the first wiring 53 side of the first connector 51 are connected so as to be capable of optical communication. Also, when the first wiring 53 is attached to the first connector 51, an end of the first power line 533 and a power line terminal 515 on the first wiring 53 side of the first connector 51 are connected so as to be conductive.
[0084] As an operation of the transmission / reception configuration unit 50, for example, when the first transmission / reception circuit board 511 detects the rotation speed of the motor 20 in the first drive unit 2, the first transmission / reception circuit board 511 receives a rotation speed detection instruction signal from the control device 19 via the first wiring 53 (first signal line 532) to the signal line terminal 514 (light receiving element) on the first wiring 53 side of the first connector 51.
[0085] Then, the first transmission / reception circuit board 511 converts the received optical signal into an electrical signal and transmits it to the encoder board 29. The encoder board 29 receives the rotation speed data from the encoder 28 and transmits it to the first transmission / reception circuit board 511. The first transmission / reception circuit board 511 converts the rotation speed data received from the encoder board 29 into an optical signal and transmits it from the signal line terminal 514 (light-emitting element) on the first wiring 53 side.
[0086] Then, the first signal line 532 of the first wiring 53 transmits an optical signal transmitted from the signal line terminal 514 (light-emitting element) to the control device 19. This enables the control device 19 to appropriately control and operate the rotation angle of the first arm 11.
[0087] As an operation of the transmission / reception configuration section 50, for example, when the first transmission / reception circuit board 511 drives the motor 20 in the first drive unit 2, the first transmission / reception circuit board 511 transmits driving power (e.g., AC current) from the control device 19 via the first wiring 53 (first power line 533) to the power line terminal 515 on the first wiring 53 side of the first connector 51. Then, the first transmission / reception circuit board 511 supplies the transmitted driving power to the stator 23 (coil 232). This causes the motor 20 to rotate.
[0088] The first transmitting / receiving circuit board 511 receives the optical signal input from the first wiring 53 at a signal line terminal 514 (light receiving element) on the first wiring 53 side, and transmits the received optical signal from a signal line terminal 512 (light emitting element) on the internal wiring 58 side to the internal wiring 58 (signal line 581).
[0089] Conversely, the first transmitter / receiver circuit board 511 receives an optical signal input from the internal wiring 58 (signal line 581) at a signal line terminal 512 (light receiving element) on the internal wiring 58 side, and transmits the received optical signal from a signal line terminal 514 (light emitting element) on the first wiring 53 side to the first wiring 53 (first signal line 532).
[0090] The first transmitter / receiver circuit board 511 receives the power signal input from the first wiring 53 at the power line terminal 515 on the first wiring 53 side, and transmits the received power signal from the power line terminal 513 on the internal wiring 58 side to the internal wiring 58 (power line 582).
[0091] The second connector 55, similarly to the first connector 51, is configured to include a second transmitting / receiving circuit board 551, a signal line terminal 552 and a power line terminal 553 on the internal wiring 58 side, and a signal line terminal 554 and a power line terminal 555 on the second wiring 57 side. As shown in Figs. 2 and 3, the second connector 55 is fixed to a support member 357 provided on a mounting portion 351 of the rigid gear 35 serving as a mounting portion of the reducer 30 on the upper end portion 22b side of the rotating shaft 22. In other words, the second connector 55 is fixed to the rigid gear 35 serving as a mounting portion of the reducer 30.
[0092] 3, the second connector 55 has a signal line terminal 552 on the internal wiring 58 side and is connected to a signal line 581 of the internal wiring 58. In addition, the second connector 55 has a power line terminal 553 on the internal wiring 58 side and is connected to a power line 582 of the internal wiring 58.
[0093] Further, the second connector 55 is disposed in the area of an opening 112 formed in a first arm housing 111 (described later) of the first arm 11 that fixes the output side of the first drive unit 2. The second connector 55 is connected to a second wiring 57 that connects to the outside. Here, the "outside" corresponds to the second connector 55 of the second drive unit 3 in this embodiment.
[0094] The signal line terminal 552 on the internal wiring 58 side of the second connector 55 includes a light emitting element and a light receiving element (both not shown) that are connected to an upper end portion, which is the other end of the signal line 581 of the internal wiring 58, via the second transmitting / receiving circuit board 551. The power line terminal 553 on the internal wiring 58 side of the second connector 55 includes a connect portion (not shown) that is connected to an upper end portion, which is the other end of the power line 582 of the internal wiring 58, via the second transmitting / receiving circuit board 551.
[0095] When the second connector 55 (second transmission / reception circuit board 551) is fixed to the support member 357, the other end of the signal line 581 of the internal wiring 58 and the signal line terminal 552 on the internal wiring 58 side are connected so as to be capable of optical communication. Also, when the second connector 55 (second transmission / reception circuit board 551) is fixed to the support member 357, the other end of the power line 582 of the internal wiring 58 and the power line terminal 553 on the internal wiring 58 side are connected so as to be conductive.
[0096] The signal line terminal 554 on the second wiring 57 side of the second connector 55 includes a light emitting element and a light receiving element (both not shown) that are connected to an end of the second signal line 572 of the second wiring 57 via the second transmitting / receiving circuit board 551. The power line terminal 555 on the second wiring 57 side of the second connector 55 includes a connect portion (not shown) that is connected to an end of the second power line 573 of the second wiring 57 via the second transmitting / receiving circuit board 551.
[0097] The second wiring 57 has a second signal line 572 and a second power line 573. The second wiring 57 is connected to the second connector 55 of the second drive unit 3. The second signal line 572 is made of optical fiber, similar to the signal line 581 of the internal wiring 58. The second power line 573 is made of a conductor, similar to the power line 582 of the internal wiring 58.
[0098] An end of the second wiring 57 between the second signal line 572 and the second power line 573 is configured as a second connecting portion 571. The second wiring 57 is detachable from the second connector 55 (second transmitting / receiving circuit board 551) by the second connecting portion 571.
[0099] When the second wiring 57 is attached to the second connector 55, an end of the second signal line 572 and a signal line terminal 554 on the second wiring 57 side of the second connector 55 are connected so as to be able to optically communicate with each other. Also, when the second wiring 57 is attached to the second connector 55, an end of the second power line 573 and a power line terminal 555 on the second wiring 57 side of the second connector 55 are connected so as to be able to be conductively connected with each other.
[0100] As an operation of the transmission / reception configuration section 50, for example, in the first drive unit 2, the second transmission / reception circuit board 551 receives a rotation speed detection instruction signal for detecting the rotation speed of the motor 20 of the second drive unit 3 from the control device 19 via the first wiring 53 (first signal line 532) and the internal wiring 58 (signal line 581) via the signal line terminal 552 (light receiving element) on the internal wiring 58 side. Then, the second transmission / reception circuit board 551 transmits the received signal to the second wiring 57 (second signal line 572) by the signal line terminal 554 (light emitting element) on the second wiring 57 side. Then, the second signal line 572 of the second wiring 57 transmits the optical signal transmitted from the signal line terminal 554 (light emitting element) on the second wiring 57 side to the second connector 55 of the second drive unit 3.
[0101] The replacement of the first drive unit 2 will now be briefly described. As shown in FIG. 2, when replacing the first drive unit 2, the first drive unit 2 is removed from the base 10 and the first arm 11.
[0102] First, in the first driving unit 2, the first connecting portion 531 connected to the first connector 51 is pulled out from the first connector 51 to remove the first wiring 53 from the first driving unit 2. Similarly, in the first driving unit 2, the second connecting portion 571 connected to the second connector 55 is pulled out from the second connector 55 to remove the second wiring 57 from the first driving unit 2.
[0103] Next, the bolt B2 is removed to release the fixation between the base housing 101 and the support member 40. Moreover, the bolt B3 is removed to release the fixation between the first arm housing 111 and the flexible gear 33. As a result of the above, the first drive unit 2 can be removed from the base 10 and the first arm 11.
[0104] According to this embodiment, the following effects can be obtained.
[0105] The first drive unit 2 of this embodiment includes a motor 20 having a rotating shaft 22 with a through hole 221, a drive section (rotor 21 and stator 23) that rotates the rotating shaft 22, and a case (first case 24) that covers at least a part of the drive section (rotor 21 and stator 23). The first drive unit 2 also includes a reducer 30 having an input section (wave generator 31) that engages with one end of the rotating shaft 22, an attachment section (rigid gear 35) that is attached to the motor 20, and an output section (flexible gear 33) that reduces the rotation of the rotating shaft 22 and outputs it. The first drive unit 2 also includes a first connector 51 that is fixed to the case (third case 26) of the motor 20 and connects to a first wiring 53 that connects to the outside, and a second connector 55 that is fixed to the attachment section (rigid gear 35) of the reducer 30 and connects to a second wiring 57 that connects to the outside. The first drive unit 2 includes internal wiring 58 that passes through the through-hole 221 and connects to the first connector 51 and the second connector 55 . With this configuration, signals and power can be transmitted and received via the internal wiring 58 that passes through the through hole 221 of the rotating shaft 22 and connects to the first connector 51 and the second connector 55. When replacing the first drive unit 2, the first wiring 53 (first connect portion 531) connected to the first connector 51 is pulled out, and the second wiring 57 (second connect portion 571) connected to the second connector 55 is pulled out. Then, the bolts B2 and B3 are removed to release the first drive unit 2 from the base 10 and the first drive unit 2 from the first arm 11. This makes it possible to remove the first drive unit 2 to be replaced. Then, the new first drive unit 2 is fixed to the base 10 and the first arm 11, and the first wiring 53 (first connect portion 531) is inserted into the first connector 51, and the second wiring 57 (second connect portion 571) is inserted into the second connector 55, thereby making it possible to replace the new first drive unit 2. Therefore, when assembling an articulated robot using the first drive unit 2 or replacing the first drive unit 2, there is no need to pull signal lines and power lines (corresponding to internal wiring 58) through or pull them out of the through holes of each drive unit, as was done in the conventional case, so that assembly and replacement work can be performed easily. Conventional robots do not assume that the drive unit will be replaced, and are connected by a single signal line from the base through the hollow part of the drive unit to the hand and the camera of the spline shaft. Therefore, even if you try to replace the drive unit, you cannot replace it while the signal line is attached to the hand, etc., and you need to remove the signal line from the hand, etc., and attach it to the hand, etc. In addition, if the signal line passes through the hollow part of another drive unit, you also need to pull out the signal line from the other drive unit and plug in the signal line. Compared to conventional drive units that required such complicated work, by providing the first connector 51 and the second connector 55 to the first drive unit, it becomes possible to replace the first drive unit 2 by simply performing the above-mentioned wiring work.
[0106] In the first driving unit 2 of the present embodiment, the internal wiring 58 has a signal line 581 and a power line 582. The first connector 51 and the second connector 55 have a signal line terminal and a power line terminal, respectively, and are connected to the signal line 581 and the power line 582 of the internal wiring 58. The signal line terminal of first connector 51 has signal line terminal 512 on the internal wiring 58 side and is connected to signal line 581. The power line terminal of first connector 51 has power line terminal 513 on the internal wiring 58 side and is connected to power line 582. The signal line terminal of second connector 55 has signal line terminal 552 on the internal wiring 58 side and is connected to signal line 581. The power line terminal of second connector 55 has power line terminal 553 on the internal wiring 58 side and is connected to power line 582. With this configuration, the first connector 51 and the second connector 55 can be connected to the signal line 581 and the power line 582 of the internal wiring 58 using their respective signal line terminals and power line terminals, thereby simplifying the assembly work for both the signal line and the power line.
[0107] In the first drive unit 2 of this embodiment, at least a portion of the rotation detector (encoder 28) is covered by the third case 26 and is installed on the motor 20 side of the rotating shaft 22 to detect the rotation of the rotating shaft 22. In the first drive unit 2, the rotation detection board (encoder board 29) is configured separately from the first connector 51 and takes in a signal from the encoder 28. The rotation detection board (encoder board 29) is connected to the first connector 51 and is connected to a signal line 581 of the internal wiring 58. With this configuration, the connection between the rotation detector (encoder 28), rotation detection board (encoder board 29), first connector 51, and signal line 581 of internal wiring 58 can be made smaller, even if the first connector 51 and the rotation detection board (encoder board 29) are configured separately.
[0108] In the first drive unit 2 of this embodiment, the support member 40 as a case has an attachment plate 45 between the case (support member 40) of the motor 20 and the mounting portion 351 of the reducer 30 in a direction along the central axis A of rotation of the rotating shaft 22, and the attachment plate 45 is attached to another member (for example, the base 10 as the first member). With this configuration, the first drive unit 2 can be fixed to another member (for example, the base 10 as the first member) by having the mounting plate 45. Furthermore, by matching the mounting plate 45 to the shape of the other member, the degree of freedom in mounting the other member to be fixed is improved.
[0109] The robot 1 of this embodiment includes the above-mentioned first drive unit 2, a base 10 as a first member having a base housing 101 as a first housing and having a first wiring 53 passing therethrough, and a first arm 11 as a second member having a first arm housing 111 as a second housing and having a second wiring 57 passing therethrough and rotating relatively to the first member. The motor 20 of the first drive unit 2 is fixed to the first member (base 10), and the output part (flexible gear 33) is fixed to the second member (first arm 11). This configuration makes it possible to realize a robot 1 that has an easily replaceable first drive unit 2 and that rotates the second member (first arm 11) relatively to the first member (base 10).
[0110] In the robot 1 of this embodiment, the second member (first arm 11) has an opening 112, and the second connector 55 is disposed in the area of the opening 112. With this configuration, the second wiring 57 can be passed from the second connector 55 to the inside of the second member (first arm 11) through the opening 112, eliminating the need for a separate connector or the like and simplifying the configuration.
[0111] 2. Second embodiment In this embodiment, assembly of the second drive unit 3 to the robot 1 will be described. Figures 4 and 5 are cross-sectional views showing a schematic configuration of a drive unit (second drive unit 3) according to this embodiment. Note that Figures 4 and 5 show cross sections passing through the second axis J2 and parallel to the XZ plane. Also, Figure 4 is a diagram in which reference numerals are mainly added to the reducer 30, first arm 11, and second arm 12 of the second drive unit 3, and Figure 5 is a diagram in which reference numerals are mainly added to the transmission and reception configuration part 50 of the second drive unit 3.
[0112] As described in the first embodiment, the second drive unit 3 is configured similarly to the first drive unit 2, and therefore, hereinafter, differences will be mainly described. Note that similar components are denoted by similar reference numerals.
[0113] The first drive unit 2 of the first embodiment is a drive unit that rotates a first arm 11 as a second member relatively to a base 10 as a first member. The second drive unit 3 of the present embodiment is a drive unit that rotates the first arm 11 as a second member relatively to a second arm 12 as a first member. The first arm 11 rotates around a first axis J1, and the second arm 12 rotates around a second axis J2.
[0114] Because they rotate relative to each other in this manner, the second drive unit 3 can be considered as a drive unit that rotates the second arm 12 as the first member relatively to the first arm 11 as the second member. In other words, the second arm 12 is rotatable around the second axis J2 with respect to the first arm 11.
[0115] In this embodiment, the motor 20 is fixed to the second arm 12 serving as the first member. In detail, in the second drive unit 3, the mounting plate 45 of the support member 40 is fixed to the second arm housing 121 that constitutes the second arm 12.
[0116] The second arm housing 121 has a shape (for example, a step portion 122) that matches the outer diameter of the mounting plate 45, and a fixing screw hole 123 is formed opposite the insertion hole 454. The support member 40 is fixed to the second arm housing 121 by positioning the support member 40 (mounting plate 45) at the step portion 122 from below the second arm housing 121, and then inserting a bolt B2 from below into the insertion hole 454 and screwing it into the fixing screw hole 123. As a result, the first wiring 53 is routed inside the second arm 12 as the first member.
[0117] In the present embodiment, the second driving unit 3 fixes the flexible gear 33 as an output section to the first arm 11 as the second member. In detail, in the second driving unit 3, the flexible gear 33 of the reducer 30 is fixed to the first arm housing 111 that constitutes the first arm 11.
[0118] The first arm housing 111 has an opening 115 described later and a shape (for example, a stepped portion 116) that matches the outer diameter of the flexible gear 33, and an insertion hole 117 is formed opposite the insertion hole 334. The flexible gear 33 is fixed to the first arm 11 by positioning the flexible gear 33 (flange portion 333) at the stepped portion 116 from above the first arm housing 111, and then inserting a bolt B3 from below through the insertion holes 117, 334 and screwing it into the fixing screw hole 355. As a result, the second wiring 57 is routed inside the first arm 11 as the second member.
[0119] With this assembly, in this embodiment, when a driving force due to the rotation of the motor 20 fixed to the second arm 12 is input to the wave generator 31 and the wave generator 31 rotates, the first arm 11 fixed to the flexible gear 33 rotates around the central axis A (second axis J2) relative to the second arm 12. If the first arm 11 is fixed, the second arm 12 rotates around the central axis A (second axis J2).
[0120] The configuration and operation of the transmission / reception configuration unit 50 will now be described. The transmission / reception component 50 of the second drive unit 3 is configured similarly to the transmission / reception component 50 of the first embodiment. In addition, the second connector 55 of the second drive unit 3 is disposed in the area of an opening 115 formed in the first arm housing 111 of the first arm 11 to which the output side of the second drive unit 3 is fixed.
[0121] 5, the second connector 55 is connected to a second wiring 57 (second connecting portion 571) that connects to the outside. Here, in this embodiment, the "outside" corresponds to the second connector 55 of the first driving unit 2. The second wiring 57 that connects to the second connector 55 of the second driving unit 3 is connected to the second wiring 57 of the first driving unit 2, and is finally connected to the second connector 55 of the first driving unit 2.
[0122] The first connector 51 of the second drive unit 3 is connected to a first wiring 53 (first connector 531) that connects to the outside. Here, in this embodiment, the "outside" corresponds to a circuit board (not shown) that transmits and receives information from the force sensor when the robot 1 is provided with a hand (not shown) or the like as an end effector.
[0123] As an operation of the transmitting / receiving configuration section 50 in the second drive unit 3, for example, a case where a rotation speed detection instruction signal for detecting the rotation speed of the motor 20 of the second drive unit 3 is received from the control device 19 will be described.
[0124] First, the rotation speed detection instruction signal is received via the second wiring 57 (second signal line 572) of the first drive unit 2. In detail, the second connector 55 of the second drive unit 3 receives the optical signal input from the second wiring 57 (second signal line 572) at the signal line terminal 554, and the second transmitting / receiving circuit board 551 causes the signal line terminal 552 to emit light and outputs the optical signal to the internal wiring 58 (signal line 581).
[0125] The first connector 51 receives and inputs an optical signal from the internal wiring 58 (signal line 581) through the signal line terminal 512, and the first transmission / reception circuit board 511 converts the received optical signal into an electrical signal and transmits it to the encoder board 29. The first transmission / reception circuit board 511 converts the rotation speed data received from the encoder board 29 into an optical signal through the signal line terminal 512 and outputs it to the internal wiring 58 (signal line 581).
[0126] The second connector 55 of the second drive unit 3 receives an optical signal input from the internal wiring 58 (signal line 581) at the signal line terminal 552, and the second transmitting / receiving circuit board 551 outputs the optical signal from the signal line terminal 554 to the second wiring 57 (second signal line 572). This optical signal is transmitted to the control device 19 via the first drive unit 2.
[0127] Further, as an operation of the transmission / reception configuration section 50 in the second drive unit 3, for example, a case where the robot 1 is provided with a hand (not shown) or the like and transmits information of a force sensor to the control device 19 will be briefly described.
[0128] In this case, the first connector 51 of the second drive unit 3 receives an optical signal output from a circuit board (not shown) that transmits and receives information from the force sensor at a signal line terminal 514 via the first wiring 53 (first signal line 532) and outputs the signal from the signal line terminal 512 to the internal wiring 58 (signal line 581). The second connector 55 of the second drive unit 3 receives an optical signal input from the internal wiring 58 (signal line 581) at a signal line terminal 552 and outputs the optical signal from the signal line terminal 554 to the second wiring 57 (second signal line 572). This optical signal is transmitted to the control device 19 via the first drive unit 2.
[0129] Moreover, as an operation of the transmission and reception configuration section 50 in the second drive unit 3, for example, a case where the motor 20 is driven will be briefly described.
[0130] In this case, driving power (e.g., AC current) for driving the motor 20 of the second driving unit 3 from the control device 19 is transmitted to the second connector 55 (power line terminal 555) of the second driving unit 3 via the first driving unit 2. Then, after being transmitted to the first connector 51 via the internal wiring 58 (power line 582) of the second driving unit 3, the driving power is supplied to the stator 23 (coil 232) to rotate the motor 20.
[0131] The replacement of the second drive unit 3 will now be briefly described. As shown in FIG. 4, when the second drive unit 3 is replaced, the second drive unit 3 is removed from the second arm 12 and the first arm 11.
[0132] First, in the second driving unit 3, the first connecting portion 531 connected to the first connector 51 is pulled out from the first connector 51, thereby removing the first wiring 53 from the second driving unit 3. Similarly, in the second driving unit 3, the second connecting portion 571 connected to the second connector 55 is pulled out from the second connector 55, thereby removing the second wiring 57 from the second driving unit 3.
[0133] Next, the bolt B2 is removed to release the fixation between the second arm housing 121 and the support member 40. Moreover, the bolt B3 is removed to release the fixation between the first arm housing 111 and the flexible gear 33. As a result, the second drive unit 3 can be removed from the second arm 12 and the first arm 11.
[0134] According to this embodiment, it is possible to obtain the same effects as those of the first embodiment.
[0135] 3. Third embodiment FIG. 6 is a partial cross-sectional view showing a schematic configuration of a drive unit (first drive unit 2A) according to this embodiment. In the first embodiment, the encoder board 29 and the first transmission / reception circuit board 511 (first connector 51) of the first connector 51 constituting the first drive unit 2 are configured as separate bodies. However, in the first drive unit 2A of the present embodiment, as shown in Fig. 6, the encoder board 29 and the first transmission / reception circuit board 511 in the first embodiment are configured integrally in the first connector 51A to configure a new first transmission / reception circuit board 511A.
[0136] Therefore, the first transmission / reception circuit board 511A has a function as the encoder board 29, for example, in the first embodiment, a function of receiving a signal from the first transmission / reception circuit board 511 and transmitting a signal from the encoder 28 to the first transmission / reception circuit board 511. The encoder board 29 and the first transmission / reception circuit board 511 in the first embodiment are integrally configured to form a new first transmission / reception circuit board 511A and are connected to the signal line 581 of the internal wiring 58. In other words, the encoder board 29 in the first embodiment is integrally configured with the first connector 51A in the present embodiment. This configuration can also be applied to the second drive unit 3.
[0137] According to this embodiment, in addition to the same effects as those of the first embodiment, the following effects can be obtained.
[0138] In the first drive unit 2A of the present embodiment, the encoder board 29 and the first transmission / reception circuit board 511 of the first embodiment are integrally configured to form a new first transmission / reception circuit board 511A that includes the encoder board and is connected to the signal line 581 of the internal wiring 58. This configuration makes it possible to shorten the distance along the central axis A from the encoder 28 to the first transmitting / receiving circuit board 511A, thereby making it possible to reduce the size of the first driving unit 2A in the direction along the central axis A. Also, the space for wiring can be further reduced compared to the first embodiment.
[0139] 4. Fourth embodiment FIG. 7 is a partial cross-sectional view showing a schematic configuration of a drive unit (first drive unit 2B) according to this embodiment. In the first embodiment, the encoder 28 and the encoder board 29 constituting the first drive unit 2 are installed at the end of the rotating shaft 22 on the motor 20 side. However, in the first drive unit 2B of the present embodiment, the encoder 28B and the encoder board 29B are installed at the end of the rotating shaft 22 on the reducer 30 side, as shown in FIG.
[0140] 7, encoder 28B as a rotation detector in this embodiment is installed at the end of rotating shaft 22 on the reducer 30 side, and detects the rotation of rotating shaft 22. Encoder board 29B as a rotation detection board is installed on the upper end 22b side of the position on rotating shaft 22 where encoder 28B is installed. The functions of encoder 28B and encoder board 29B are similar to those of encoder 28 and encoder board 29 in the first embodiment.
[0141] The encoder board 29B is fixed to a support member 358 configured to protrude from a support member 357 provided at an attachment portion 351 of the rigid gear 35 serving as a fixed portion of the reducer 30. The encoder board 29B is also connected to the second connector 55 (second transmitting / receiving circuit board 551) and to a signal line 581 of the internal wiring 58. This configuration can also be applied to the second drive unit 3.
[0142] According to this embodiment, in addition to the same effects as those of the first embodiment, the following effects can be obtained.
[0143] In the first drive unit 2B of the present embodiment, the encoder 28B as a rotation detector is disposed on the reducer 30 side of the rotating shaft 22 and detects the rotation of the rotating shaft 22. The encoder board 29B as a rotation detection board takes in a signal from the encoder 28B and is disposed on the reducer 30 side. The encoder board 29B is connected to the second connector 55 and is connected to a signal line 581 of the internal wiring 58. This configuration makes it possible to improve the degree of freedom in arranging the encoder 28B and the encoder board 29B in the first drive unit 2B.
[0144] 5. Variation 1 In this embodiment, the first drive unit 2 is removed from the base 10 and the first arm 11, but the first drive unit 2 itself can also be separated into the motor 20 and the reducer 30 and reassembled. In that case, since the first connector 51 and the second connector 55 are connected by the internal wiring 58, there is no need to adjust the alignment of the optical axis.
[0145] 6. Variation 2 In this embodiment, the signal line 581 of the internal wiring 58, the first signal line 532 of the first wiring 53, and the second signal line 572 of the second wiring 57 are made of optical fibers. However, they are not limited to this, and may be made of normal conductors (lead wires) to transmit electrical signals.
[0146] 7. Variation 3 In this embodiment, a horizontal articulated robot is taken up and described as a robot incorporating drive units (the first drive unit 2 and the second drive unit 3). However, this is not limited thereto, and a vertical articulated robot may be used as a robot incorporating drive units (the first drive unit 2 and the second drive unit 3), and similar effects can be obtained. [Explanation of symbols]
[0147] Reference Signs List 1...robot, 2...first drive unit, 3...second drive unit, 10...base, 11...first arm, 12...second arm, 20...motor, 21...rotor as drive unit, 22...rotating shaft, 23...stator as drive unit, 24...first case as case, 25...second case as case, 26...third case as case, 28...encoder as rotation detector, 29...encoder board as rotation detection board, 30...reduction gear, 31...wave generator as input unit, 33...output unit Flexible gear, 35...rigid gear as mounting part, 40...support member as case, 45...mounting plate, 50...transmitting / receiving component, 51...first connector, 53...first wiring, 55...second connector, 57...second wiring, 58...internal wiring, 101...base housing, 111...first arm housing, 112...opening, 115...opening, 121...second arm housing, 221...through hole for rotating shaft, 512, 552...terminal for signal line on internal wiring side, 513, 553...terminal for signal line on internal wiring side, 581...signal line, 582...power line.
Claims
1. a motor having a rotating shaft provided with a through hole, a drive unit that rotates the rotating shaft, and a case that covers at least a part of the drive unit; a reducer including an input portion that engages with one end of the rotating shaft, a mounting portion that is mounted to the motor, and an output portion that reduces the rotation of the rotating shaft and outputs the reduced rotation; a first connector fixed to the case of the motor and connected to a first wiring connected to an external device; a second connector fixed to the mounting portion of the reducer and connected to a second wiring connected to an external device; and internal wiring that passes through the through hole and is connected to the first connector and the second connector.
2. the internal wiring includes a signal line and a power line; 2. The drive unit according to claim 1, wherein the first connector and the second connector each have a terminal for a signal line and a terminal for a power line, and are connected to the signal line and the power line of the internal wiring.
3. a rotation detector that is at least partially covered by the case and is disposed on the motor side of the rotating shaft and detects rotation of the rotating shaft; a rotation detection board that receives a signal from the rotation detector and is configured separately from the first connector, The drive unit according to claim 2 , wherein the rotation detection board is connected to the first connector and to the signal line of the internal wiring.
4. The drive unit includes a rotation detector that is at least partially covered by the case and detects rotation of the rotation shaft; a rotation detection board that receives a signal from the rotation detector and is integrally formed with the first connector, 3. The drive unit according to claim 2, wherein the rotation detection board is connected to the signal line of the internal wiring.
5. a rotation detector for detecting rotation of the rotating shaft; a rotation detection board that receives a signal from the rotation detector and is installed on the reducer side, The drive unit according to claim 2 , wherein the rotation detection board is connected to the second connector and to the signal line of the internal wiring.
6. A drive unit according to any one of claims 1 to 5; a first member having a first housing and through which the first wiring passes; a second member having a second housing, through which the second wiring passes, and rotating relatively to the first member; The motor is fixed to the first member, The robot, wherein the output portion is fixed to the second member.
7. The second member has an opening, 7. The robot according to claim 6, characterized in that the second connector is arranged in the area of the opening.
8. a mounting plate is provided between the case of the motor and the mounting portion of the reducer in a direction along a central axis of rotation of the rotation shaft; 8. The robot according to claim 6 or claim 7, wherein the mounting plate is attached to the first member.
Citation Information
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