JP2020075328A - Robot arm and robot device - Google Patents

Abstract

To provide a robot arm which can be driven in a small space by superimposing and folding its links, and whose inter-link joints have a small revolving diameter.SOLUTION: Provided is a robot arm that carries out a prescribed operation, when drive of driving sources is transferred to its links via a speed reducer so that the links rotate. In the robot arm, a driving source for driving a second link and a second auxiliary link is disposed in a first link, and a driving source for driving a third link is disposed in the third link. Further, wiring laid in the driving source for driving the second link and the second auxiliary link is laid via an internal part of the first link, and wiring laid in the driving source for driving the third link is laid via internal parts of a first auxiliary link and the second auxiliary link.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a robot arm and a robot device.

  In many industries, robot devices using articulated robot arms have been used so far for labor saving and automation of factory production lines. Particularly in recent years, automation of production lines has accelerated due to the declining birthrate and rising labor costs. Further, in order to effectively utilize the limited space of the factory to increase the number of robot arms installed and improve the efficiency of the production line, downsizing of the robot arms is also required.

  The robot arm described in Patent Document 1 has a mechanism in which a part of links forming the robot arm can be overlapped and folded. By doing so, when the tip of the robot arm is moved from the predetermined position to the opposite position, the robot arm is moved through the posture in which the link is folded so that the robot arm does not rotate significantly and The tip of the arm can be moved from a predetermined position to the opposite position.

  As a result, the space required to prevent interference with other devices during the operation of the robot arm can be reduced. Therefore, the space required for installing the robot arm can be reduced, and many robot arms can be installed in the limited space of the factory.

JP, 2016-068226, A

  However, in the configuration described in Patent Document 1, since the robot arm can be folded by overlapping a part of the link, the movable angle of each joint that drives the link becomes large. Therefore, for wiring such as a sensor mounted on a joint having a large movable angle, a large wiring processing space must be secured according to the movable angle in order to secure the durability of the wiring.

  Moreover, a drive device such as a speed reducer is often arranged at the joint where the wiring processing space is arranged, and it is difficult to secure a sufficient wiring processing space. As a result, in order to secure the wiring processing space, for example, the wiring is wound around the speed reducer, and the joint portion of the robot arm becomes large.

  In view of the above problems, it is an object of the present invention to reduce the size increase of joints while sufficiently securing the wiring processing space in joints having a large movable angle.

  In order to solve the above problems, in the present invention, a drive of a drive source is transmitted to a link through a speed reducer, the link is rotated, and a robot arm that performs a predetermined operation is provided. A first link that is connected to the base and rotates on a first rotation shaft; a first auxiliary link provided on the first link; and a first link that is connected to the first link and rotates on a second rotation shaft. The second link includes two links, a second auxiliary link that is driven to follow the driving of the second link, and a third link that is connected to the second link and that rotates on a third rotation shaft. And the second auxiliary link and the third auxiliary link are rotatable relative to each other so as to overlap each other when viewed from a predetermined direction, and drive the second auxiliary link and the second auxiliary link. Is provided in the first link, and the drive source for driving the third link is provided in the third link, and is for driving the second link and the second auxiliary link. The wiring arranged in the driving source is arranged through the inside of the first link, and the wiring arranged in the driving source for driving the third link includes the first auxiliary link and the second auxiliary link. A robot arm is adopted, which is characterized by being arranged through the inside of the auxiliary link.

  According to the present invention, the wiring processing space of the robot arm can be arranged without using a drive device such as a speed reducer. Therefore, it is possible to reduce the size increase of the joint portion of the robot arm.

It is a schematic diagram which shows the schematic structure of the robot apparatus 1000 in 1st Embodiment. FIG. 3 is a block diagram of a robot device 1000 according to the first embodiment. 3 is a control block diagram showing a control system of the robot apparatus 1000 according to the first embodiment. FIG. FIG. 3 is a schematic cross-sectional view of a joint J ₂ and an auxiliary joint J _2S of the robot arm body 200 according to the first embodiment. FIG. ₃ is a schematic cross-sectional view of a joint J ₃ and an auxiliary joint J _3S of the robot arm body 200 according to the first embodiment.

  Embodiments for carrying out the present invention will be described below with reference to the embodiments shown in the accompanying drawings. It should be noted that the following embodiments are merely examples, and for example, the detailed configuration can be appropriately changed by those skilled in the art without departing from the spirit of the present invention. The numerical values taken in this embodiment are reference numerical values and do not limit the present invention.

(First embodiment)
FIG. 1 is a plan view of a robot apparatus 1000 according to this embodiment as seen from an arbitrary direction of an XYZ coordinate system. 1A shows an XZ plan view, and FIG. 1B shows a YZ plan view. In the following drawings, arrows X, Y, and Z in the drawings indicate the coordinate system of the entire robot apparatus 1000. Generally, in a robot apparatus, as the XYZ three-dimensional coordinate system, in addition to the global coordinate system of the entire installation environment, a local coordinate system may be appropriately used for the robot hands, fingers, etc. depending on control reasons. In this embodiment, the coordinate system of the entire robot apparatus 1000 is represented by XYZ, and the local coordinate system is represented by xyz.

  As shown in FIG. 1, the robot apparatus 1000 includes a multi-joint robot arm main body 200, a robot hand main body 300, a robot arm main body 200, and a control device 400 that controls the operation of the robot hand main body 300.

  The external input device 500 is provided as a teaching device that transmits teaching data to the control device 400. A teaching pendant is given as an example of the external input device 500, and is used by the operator to specify the operation of the robot arm body 200 or the robot hand body 300.

  The robot arm main body 200 of the present embodiment has a robot hand main body 300 attached as an end effector, and has a structure of vertical articulation. Hereinafter, the case where the end effector is the robot hand body 300 will be described, but the end effector is not limited to this.

  Further, the robot arm main body 200 is fixed with the base 209 embedded in the pedestal B. In the present embodiment, the robot arm body 200 is described as being vertically downward (-Z direction), but the orientation may be changed depending on the use case.

  The robot hand main body 300 holds an object such as a part or a tool. The robot hand main body 300 of the present embodiment opens and closes two fingers by a drive mechanism (not shown) to hold or release the object. It suffices if the object can be gripped so as not to be displaced relative to the robot arm body 200.

  The robot arm main body 200 has a plurality of joints, for example, 6 joints (6 axes). The robot arm main body 200 includes a plurality (six) of servo motors 211 to 216 that rotate and drive the joints J1 to J6 around the rotation axes A1 to A6, respectively.

In the robot arm main body 200, a plurality of links 210 _{0 to} 210 ₆ are rotatably connected by the joints J _{1 to} J ₆ . Here, from the base end of the robot arm body 200 distally, the link ₂₁₀ 0-210 ₆ is coupled in order.

1B, the links 210 ₁ and 210 ₂ are provided with auxiliary links 210 _1S and 210 _2S which rotate via joints J _2S and J _3S .

The link 210 ₂ is supported on the link 210 ₁ by a joint J ₂ . Here, in the joint J ₂ , the motor 212 is provided on the link 210 ₁ , and the transmission mechanism 231 is provided to rotate the link 210 ₂ about the A ₂ axis. In this embodiment, a timing belt is used as the transmission mechanism 231. Of course, those skilled in the art may use another transmission mechanism such as a bevel gear as the transmission mechanism 231.

The link 210 _{1, A 1} auxiliary link axis as a reference to the link 210 ₁ and symmetric _{210 1S} is attached.

Auxiliary link _{210 1S} supports the auxiliary link _{210 2S} by the auxiliary joint _{J 2S} that a rotation about the same _{A 2-axis} and the rotation center of the joint _{J 2.}

The auxiliary link 210 _2S is connected to the auxiliary link 210 ₃ by an auxiliary joint J _3S whose rotation center is the A ₃ axis which is the same as the rotation center of the joint J ₃ .

As a result, the joints J _2S and J _3S can be driven in synchronization with the joints J ₂ and J _3, and within the movable range, the robot arm can be brought into a posture in any of three directions at any three-dimensional position. The end effector of the main body 200 (robot hand main body 300) can be turned.

  The position and orientation of the robot arm body 200 can be expressed in a coordinate system. The coordinate system To in FIG. 1 represents the coordinate system fixed to the base end of the robot arm body 200, that is, the pedestal B, and the coordinate system Te is the coordinate system fixed to the hand of the robot arm body 200 (robot hand body 300). Represent

  Here, the hand of the robot arm main body 200 is the robot hand main body 300 when the robot hand main body 300 does not grip an object in the present embodiment. When the robot hand main body 300 grips an object, the robot hand main body 300 and the gripped object (for example, parts or tools) are referred to as the hands of the robot arm main body 200. That is, regardless of whether the robot hand main body 300 is holding an object or not holding the object, the robot hand main body 300 that is an end effector is referred to as a fingertip.

Each of the joints J _{1 to} J ₆ has a motor 211 to 216 and a speed reducer 271 to 276 for transmitting the drive of each motor 211 to 216 to each link. Reducer 271-276 are connected directly, or the link ₂₁₀ 0-210 ₆ driven by the joints through the transmission mechanism 231 and transmission member such as a bearing.

  Further, as will be described later, the robot arm main body 200 is provided with torque sensors 221 to 226 and position sensors 541 to 546 that detect a relative displacement amount between the links (FIG. 2).

  Inside the base 209, a servo control unit 230 as a drive control unit that controls the drive of the motors 211 to 216 is arranged.

The servo control unit 230, based on the torque command value corresponding to each joint _J 1 through J ₆ entered, so that the torque of each joint _J 1 through J ₆ to follow the torque command value, each motor 211 to 216 It outputs a current and controls the drive of each motor 211-216.

  In addition, in the present embodiment, the servo control unit 230 is described as being configured by one control device, but is configured by an assembly of a plurality of control devices respectively corresponding to the motors 211 to 216. Good. Further, in the present embodiment, the servo control unit 230 is arranged inside the base 209, but it may be arranged inside the control device 400.

  With the above configuration, it is possible to fold a part of the link of the robot arm main body 200 and move the robot hand main body 300 to an arbitrary position to perform a desired work. Examples of the desired work include a work of gripping a predetermined work by the robot hand main body 300 and manufacturing an article.

  FIG. 2 is a block diagram showing the robot apparatus 1000 according to this embodiment. The control device 400 connected to the robot device 1000 is configured by a computer, and includes a CPU (Central Processing Unit) 401 as a control unit (processing unit).

  Further, the control device 400 includes a ROM (Read Only Memory) 402, a RAM (Random Access Memory) 403, and an HDD (Hard Disk Drive) 404 as a storage unit. The control device 400 also includes a recording disk drive 405 and various interfaces 406 to 409.

  A ROM 402, a RAM 403, an HDD 404, a recording disk drive 405, and various interfaces 406 to 409 are connected to the CPU 401 via a bus 410. The ROM 402 stores basic programs such as BIOS. The RAM 403 is a storage device that temporarily stores various data such as the calculation processing result of the CPU 401.

  The HDD 404 is a storage device that stores the calculation processing result of the CPU 401, various data acquired from the outside, and the like, and also records a program 430 for causing the CPU 401 to execute the calculation processing. The CPU 401 executes each step of the robot control method based on the program 430 recorded (stored) in the HDD 404.

  The recording disk drive 405 can read various data, programs, etc. recorded on the recording disk 431.

  The external input device 500 is connected to the interface 406. The CPU 401 receives input of teaching data from the external input device 500 via the interface 406 and the bus 410.

  The servo control unit 230 is connected to the interface 409. The servo control unit 230 drives the motors 211 to 216, detects the torque between the links and the relative displacement amount generated by the driving of the motors from the torque sensors 221 to 222 and the position sensors 541 to 546, and receives the detection results.

  Then, the CPU 401 acquires the detection results from the torque sensors 221 to 226 and the position sensors 541 to 546 via the servo control unit 230, the interface 409 and the bus 410. Further, the CPU 401 outputs the torque command value and the position command data of each joint to the servo control unit 230 via the bus 410 and the interface 409 at predetermined time intervals.

  A monitor 421 is connected to the interface 407, and various images are displayed on the monitor 421 under the control of the CPU 401. The interface 408 is configured so that an external storage device 422, which is a storage unit such as a rewritable nonvolatile memory or an external HDD, can be connected.

  In this embodiment, the computer-readable recording medium is the HDD 404 and the program 430 is stored in the HDD 404, but the present invention is not limited to this. The program 430 may be recorded in any recording medium as long as it is a computer-readable recording medium.

  For example, as the recording medium for supplying the program 430, the ROM 402, the recording disk 431, the external storage device 422, etc. shown in FIG. 2 may be used. Explaining with a specific example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory, a ROM, or the like can be used as the recording medium.

  FIG. 3 is a control block diagram showing a control system of the robot apparatus in this embodiment. The CPU 401 (FIG. 2) of the control device 400 functions as the force control unit 504 and the position target value generation unit 505 by executing the program 430 (FIG. 2).

  The servo control unit 230 functions as a plurality (six since it has six joints) of switching control units 511 to 516, a plurality of position control units 521 to 526, and a plurality of motor control units 531 to 536.

  The torque sensors 221 to 226 (torque detecting means) detect the torque generated between the links, and the position sensors 541 to 546 detect the relative movement amount between the links. An example of the position sensor is an encoder.

In the present embodiment, the position sensor 541 to 546 detects the angle _q 1 to q ₆ as a relative displacement amount between the direct link. The torque sensors 221 to 226 detect the torques τ _{1 to} τ ₆ of the joints J _{1 to} J ₆ , respectively.

The external input device 500 outputs the force target value F _d included in the force teaching data 501 and the position target value P _d included in the position teaching data 502 to the CPU 301 according to the operation of the operator. The force target value F _d is a target value of the force generated by the hand of the robot arm body 200, and is set by the operator using the external input device 500.

The position target value P _d is a target value of the position of the hand of the robot arm main body 200, and is set by the operator using the external input device 500. A robot model 503 is stored in the external storage device 422.

The force control unit 504 inputs the robot model 503 including the hand load model, the force target value F _d , the position target value P _d , the current position P, and the force F. Then, the force control unit 504 uses these values to determine the torque command value τ _Fd1 ~τ _Fd6 for each joint _J 1 through J _6.

At this time, the force deviation and hand force F and the force target value F _d, to obtain a torque command value τ _Fd1 ~τ _Fd6 as positional deviation between the hand position P (t) and the target position value P _d becomes smaller. The force control unit 504 _{outputs the} calculated torque command values τ _{Fd1 to} τ _Fd6 to the switching control units 511 to 516, respectively.

The position target value generation unit 505 obtains the angle command values (position command values) q _{d1 to} q _d6 of the joints J _{1 to} J ₆ from the position target value P _d of the hand by inverse kinematics calculation, and the angle command values q. the _d1 to q _d6 outputs to the position control unit 521 to 526.

Each position control unit 521 to 526, the torque command so that the angular deviation between the angle _q 1 to q ₆ of each joint _J 1 through J ₆ and angle command value _q d1 _{to q d6} of the joints _J 1 through J ₆ is reduced Values τ _{Pd1 to} τ _Pd6 are _calculated . The position control units 521 to 526 output the torque command values τ _{Pd1 to} τ _Pd6 to the switching control units 511 to 516, respectively.

Each of the switching control units 511 to 516 controls switching between a force control mode for performing torque-based force control and a position control mode for performing position control. Each switch control unit 511 to 516, the force control mode is output to each motor control unit 531 to 536 each torque command value τ _Fd1 ~τ _Fd6 as the torque command value _{τ d1 ~τ d6.} Each switch control unit 511 to 516, the position control mode is output to each motor control unit 531 to 536 each torque command value τ _Pd1 ~τ _Pd6 as the torque command value _{τ d1 ~τ d6.}

Each motor control unit 531 to 536 sets each current Cur _{1 to} Cur ₆ so as to realize each torque command value τ _{d1 to} τ _d6 based on the angle (position) θ _{1 to} θ ₆ of each electric motor 211 to 216. The motors 211 to 216 are energized.

  With the above configuration, the robot arm main body 200 can be made to execute position control controlled by position information and force control controlled by force information such as torque.

  Next, referring to the drawings, in the robot arm main body 200 of the present embodiment, drive mechanisms for joints that drive foldable links, arrangement and structure of sensors provided at those joints, and wiring connected to the sensors. The processing will be described.

4, the robot arm body 200, the joint _{J 2} is a connecting portion between the link 210 ₁ and the link 210 _2, schematically between the auxiliary link _{210 1S} is a connection portion between the auxiliary link _{210 2S} auxiliary joint _{J 2S} FIG. 4A shows the joint J ₂ , and FIG. 4B shows the joint J _2S .

As shown in FIG. 4A, the link 210 ₁ stores a motor 212 that is a drive source for actively rotating the link 210 ₂ about the axis A ₂ . The motor output shaft 234 that outputs the rotation of the motor 212 is connected to the timing pulley (driving pulley) 232, the output from the motor 212 is transmitted to the link 210 ₂ by a timing belt 231.

The link 210 _1, bearing 250 is disposed a supporting mechanism for supporting the relatively rotatable link 210 ₂ for the link 210 _1.

A speed reducer 272 is disposed on the axis of the shaft A ₂ , a timing pulley (driven side pulley) 233 is connected to the speed reducer input shaft 235, and the timing pulley 232 connects the driving side pulley 232. To be done.

Further, the reduction gear 272 is provided with a reduction gear output shaft 236 for outputting the torque inputted from reducer input shaft 235 to expand by the amount of the predetermined reduction ratio to the link 210 _2. The reducer output shaft 236 is connected to the link 210 ₂ via a bearing 250.

With the above arrangement, when the driving link 210 _2, the motor 212 is driven by a servo controller 230, the output torque from the motor 212 is a current controlled so as to follow the command value from the servo controller 230.

  The torque generated by the motor 212 is input to the speed reducer 272 via a power transmission system including a motor output shaft 234, a driving side pulley 232, a timing belt 231, a driven side pulley 233, and a speed reducer input shaft 235. ..

Then, the speed reducer 272 converts the torque into an appropriate level for driving the link 210 ₂ (enlarged by the speed reduction ratio), and outputs the torque from the speed reducer output shaft 236 to rotationally drive the link 210 ₂ .

Here, the speed reducer 272 is fixed to the link 210 ₁ via the torque sensor 222. As described above, by disposing the torque sensor 222 on the link side to which the speed reducer 272 is fixed, an anti-torque as a reaction of the output torque output by the speed reducer 272 acts on the torque sensor 222.

The torque applied to the link 210 ₂ can be controlled by controlling the motor 212 by the servo controller 230 so that the counter torque follows the desired command torque.

Next, the auxiliary joint J _2S will be described in detail with reference to FIG. The auxiliary joint J _2S is configured by connecting the auxiliary link 210 _1S and the auxiliary link 210 _2S via a bearing 251.

Further, the link 210 _1S and the link 210 _2S are respectively provided with duct-shaped wire introducing portions 280 and 281 having a hollow structure along the axis A ₂ which is the center of rotation of the joint. It has a smooth shape so that the durability of the wiring 240 can be secured even when the wiring 240 slides inside the robot arm due to the relative rotation of the auxiliary link 210 _1S and the auxiliary link 210 _2S .

Further, the auxiliary joint J _2S is provided with a position sensor 542. The position sensor 542 is composed of a scale portion 542S and a detection portion 542D that are arranged circumferentially around the axis A ₂ .

With the rotation of the link 210 _2S , the scale portion 542S and the detection portion 542D are relatively displaced, and the relative displacement amount is detected by the detection portion 542D, whereby the relative displacement amount of the auxiliary link 210 _1S and the auxiliary link 210 _2S. To detect.

Since the joint J ₂ auxiliary joint J _2S driven synchronously, to measure the angle of the auxiliary joint J _2S is the same as measuring the angle of the joint J _2, joint J ₂ and the auxiliary joint J _2S It becomes possible to control the positions of and.

Inside the auxiliary joint _{J 2S,} auxiliary joint _{J 2S} is installed in the link ₂₁₀ 3-210 ₆ of the end side of the motor 213 to 216, the torque sensor 553 to 556, Ya power to such as the position sensor 543 to 546 A wiring 240 for exchanging signals is provided.

Further, the position sensor 542 has position sensor wirings 240E1 and 240E2 for supplying power and exchanging signals with the servo controller 230 and the robot controller 400. As shown in FIG. 4B, the auxiliary link is provided. When 210 _1S and 210 _2S are connected via the bearing 251, the wiring introducing portions 280 and 281 are also connected and a hollow portion for passing the wiring 240 is formed.

The position sensor wirings 240E1 and 240E2 join the wiring 240 in the auxiliary link 210 _1S and are introduced to the base 209.

In this way, by making the inside of the auxiliary joint J _2S hollow by the wiring introducing portions 280 and 281, that space can be utilized as a space for wiring processing. Therefore, the wiring 240 can be provided without the reduction gear 272.

Further, as shown in FIG. 4A, a torque sensor wiring 241 for transmitting the driving torque of the joint J ₂ detected by the torque sensor 222 to the servo controller 230 and the control device 400 is provided inside the link 210 _1. There is. Torque sensor wiring 241 is provided so as to join the wiring 240 in the vicinity of the motor 212 provided in the link 210 _1.

The torque sensor 222 is provided on the link 210 ₁ which is a link that is not relatively displaced when the link 210 ₂ is driven. Therefore, the torque sensor wiring 241 can be provided inside the robot arm body 200 without the reduction gear 270.

FIG. 5 shows a schematic cross-sectional view of the mechanism of the joint J ₃ and the auxiliary joint J _3S in the robot arm body 200 of this embodiment. The left side in FIG. 5 shows the joint J ₃ , and the right side shows the auxiliary joint J _3S .

First, the link 210 ₃ is connected to the link 210 ₂ and the auxiliary link 210 _2S . The link 210 ₂ is connected to the link 210 ₃ via a bearing 252, and the link 210 _2S is connected to the link 210 ₃ via a bearing 253.

The link 210 ₃ stores a speed reducer 273 for driving the link 210 ₃ and a motor 213. Motor 213 is a command value from the servo controller 230, the torque output from the motor 213 to the link 210 ₃ is rotated by being controlled so as to follow the command value.

The motor 213 is an electromagnetic motor, and a brushless DC motor or an AC servomotor can be exemplified. Motor 213 in the inside space of the link 210 _3, to be supported with a gap between the link 210 ₃ and the motor 213 are mounted in fastening by screws to the motor flange 290. The torque output from the motor 213 is transmitted to the speed reducer 273 via the speed reducer input shaft (not shown) as the motor output shaft 238 rotates.

  The speed reducer 273 reduces the rotation amount of the motor 213 to 1 / N and transmits it to the speed reducer output shaft 237. Examples of the speed reducer 273 include a spur gear train and a wave gear speed reducer.

The reducer output shaft 237 that outputs the torque after deceleration is connected to the link 210 ₂ via the bearing 252. Further, one of the bearings 252 is attached to the motor flange 290, and the other is attached to the speed reducer output shaft 237. An example of the bearing 252 is a cross roller bearing.

With the above configuration, the motor flange 290 relatively rotates about the rotation center (A3) of the bearing 252. Other motor flange 290 is constructed integrally with the links 210 ₃ via the torque sensor 223. Thus, the motor flange 290 is link 210 ₂ and rotates relative to the auxiliary link _{210 2S,} it is possible to relatively rotate link 210 ₃ also relative to the link 210 _2, the auxiliary link _{210 2S} via the torque sensor 223.

Then, since the torque output from the reduction gear 273 is transmitted to the link 210 ₃ via the torque sensor 223, the torque applied to the link 210 ₃ can be detected by the torque sensor 223.

Further, the link 210 _2S is provided with a duct-shaped wiring introduction portion 282 having a hollow structure along the axis A3 which is the rotation center of the link 210 ₃ . Wire introducing portion 282, so that wiring 240 in accordance with the relative rotation between the link 210 ₃ auxiliary link 210 _2S can ensure the durability of the even lines when the slide inside the robot arm, has a smooth shape ..

Further, the auxiliary joint J _3S is provided with a position sensor 543. Position sensor 543 is composed of a scale portion 543S which is disposed circumferentially of the axis _{A 3,} by the detection unit 543D.

With the rotation of the link 210 ₃ , the scale portion 543S and the detection portion 543D are relatively displaced, and the relative displacement amount of the auxiliary link 210 _2S and the link 210 ₃ is detected by detecting the relative displacement amount by the detection portion 543D. To detect.

Since the joint J ₃ auxiliary joint J _3S driven synchronously, to measure the angle of the auxiliary joint J _3S is equivalent to measuring the angle of the joint J _3, the joint J ₃ and the auxiliary joint J _3S It becomes possible to control the positions of and.

Inside the auxiliary joint _{J 3S,} auxiliary joint _{J 3S} of including the hand side of the link ₂₁₀ 3-210 ₆ motor is installed in the 213-216, the torque sensor 223 to 226, power to such as the position sensor 543 to 546 A wiring 240 for supplying and exchanging signals is provided.

  Further, the position sensor 543 has position sensor wirings 240E3 and 240E4 for supplying power and exchanging signals with the servo controller 230 and the robot controller 400.

As shown in FIG. 5, when the auxiliary link 210 _2S and the link 210 ₃ are connected via the bearing 252, the wiring introducing portion 282 is a space for installing the motor 213 provided inside the link 210 _3. Connected to. Then, a hollow portion for passing the wiring 240 is formed.

The position sensor wirings 240E3 and 240E4 join the wiring 240 in the auxiliary link 210 _2S and are introduced into the base portion 209.

In this way, by making the inside of the auxiliary joint J _3S hollow by the wiring introducing portion 282, the space can be utilized as a space for wiring processing. Therefore, the wiring 240 can be provided without the reduction gear 273.

Further from FIG. 5, the internal link 210 _3, the torque sensor wiring 243 for transmitting the driving torque by the torque sensor 223 detects the servo controller 230 and the controller 400 are provided.

  The torque sensor 223 is provided in a portion adjacent to the space where the wiring 240 is provided. Therefore, the torque sensor wiring 243 can be provided without using the speed reducer 270.

  As described above, the robot arm main body 200 according to the present embodiment has a configuration in which the wiring route of the wiring provided to the motor provided in the foldable link and the placement route of the motor are separate. Therefore, the wiring can be arranged without interposing the reduction gear.

  As a result, it is not necessary to provide a complicated wiring processing space, such as a coil around the reduction gear, in the joint, and it is possible to reduce the size of the joint.

  As a result, the turning diameter of each joint of the robot arm body can be reduced. As a result, the space for avoiding the interference of the robot arm body can be reduced, and the workability of the robot arm can be prevented from being deteriorated.

  The configuration of the joints of the robot arm body in the above embodiment is not limited to this, and those skilled in the art can arbitrarily change the design. In addition, each motor is not limited to the above-described configuration, and the drive source that drives each joint may be, for example, a device such as an artificial muscle.

  Further, although the robot arm main body is described as being suspended from the ceiling in the above-described embodiments, the robot arm main body can be applied to a robot that is placed on the floor, hung on a wall, or installed on an inclined surface. Further, it is applicable to a machine capable of automatically performing expansion / contraction, flexion / extension, vertical movement, horizontal movement or turning operation or a combined operation thereof based on the information in the storage device of the control device.

200 Robot arm main body 209 Base 210 _{0 to} 210 ₆ Link 210 _1S , 210 _2S Auxiliary link 211 to 216 Motor 221 to 226 Torque sensor 230 Servo control device 231 Timing belt 232, 233 Timing pulley 234, 238 Motor output shaft 235 Reducer Input shaft 236, 237 Reducer output shaft 240 Wiring 240E1, 240E2, 240E3, 240E4 Position sensor wiring 241, 243 Torque sensor wiring 250, 251, 252, 253 Bearings 271-276 Speed reducer 280, 281, 282 Wiring introduction unit 300 Robot the hand body 400 controller 500 external input device 541 to 546 position sensor 542s, 543s scale 542D, 543D detector J ₁ through J ₆ joint J _{2S, J 3S} auxiliary joint

Claims (15)

A robot arm that transmits a drive of a drive source to a link through a speed reducer, rotates the link, and performs a predetermined operation,
Base
A first link that is connected to the base and rotates about a first rotation axis;
A first auxiliary link provided on the first link;
A second link that is connected to the first link and that rotates on a second rotation axis;
A second auxiliary link driven following the drive of the second link;
A third link which is connected to the second link and rotates on a third rotation shaft;
The second link, the second auxiliary link, and the third link are relatively rotatable to a position in which they overlap each other when viewed from a predetermined direction,
A drive source for driving the second link and the second auxiliary link is provided in the first link,
A drive source for driving the third link is provided in the third link,
The wiring arranged in the drive source for driving the second link and the second auxiliary link is arranged via the inside of the first link,
The robot arm, wherein the wiring arranged in a driving source for driving the third link is arranged inside the first auxiliary link and the second auxiliary link. The robot arm according to claim 1,
A speed reducer connected to a drive source for driving the second link and the second auxiliary link is provided in the first link,
The robot arm, wherein a speed reducer connected to a drive source for driving the third link is provided on the third link. The robot arm according to claim 1 or 2,
The wiring arranged in the driving source for driving the second link and the second auxiliary link and the wiring arranged in the driving source for driving the third link do not go through the speed reducer. A robot arm characterized by being arranged in. The robot arm according to any one of claims 1 to 3,
The second auxiliary link is provided with a first duct at a connecting portion between the first auxiliary link and the second auxiliary link, and a first bearing so that the second auxiliary link can rotate on the second rotary shaft. Is connected to the first auxiliary link via
The third link is provided with a second duct at a connecting portion between the second auxiliary link and the third link, and is provided with a second bearing so as to be rotatable on the third rotation shaft. Connected to the second auxiliary link,
A robot arm, wherein wiring arranged in a drive source for driving the third link passes through the first duct and / or the second duct. The robot arm according to any one of claims 1 to 4,
A first position sensor that detects a relative displacement between the first auxiliary link and the second auxiliary link is provided at a connecting portion between the first auxiliary link and the second auxiliary link,
A second position sensor that detects a relative displacement between the second auxiliary link and the third link is provided at a connecting portion between the second auxiliary link and the third link,
The wiring to the first position sensor is provided inside the first auxiliary link,
The robot arm, wherein the wiring to the second position sensor is provided inside the first auxiliary link and the second auxiliary link. The robot arm according to claim 4 or 5,
A first torque sensor that detects a torque generated between the first link and the second link is provided at a connecting portion between the first link and the second link,
A second torque sensor that detects a torque generated between the second link and the third link is provided at a connecting portion between the second link and the third link,
The wiring to the first torque sensor passes through the inside of the first link,
The robot arm, wherein the wiring to the second torque sensor passes through the inside of the first auxiliary link, the first duct, the inside of the second auxiliary link, and the second duct. The robot arm according to any one of claims 1 to 6, wherein
The robot arm, wherein the first auxiliary link is provided so as to be symmetrical with respect to the first link with respect to the first rotation axis. The robot arm according to any one of claims 1 to 7,
The robot arm is a ceiling-mounted type.   A robot apparatus comprising the robot arm according to any one of claims 1 to 8 and a robot hand. A robot arm that transmits a drive of a drive source to a link through a speed reducer, rotates the link, and performs a predetermined operation,
A first link that rotates on a first axis of rotation;
A first auxiliary link driven following the drive of the first link;
A second link that is connected to the first link and the first auxiliary link and rotates on a second rotation shaft;
The first link, the first auxiliary link, and the second link are relatively rotatable to a position in which they overlap each other when viewed from a predetermined direction,
The wiring arranged inside the second link is arranged via the first auxiliary link, and the speed reducer transmitting the drive of the second link is provided between the first link and the second link. A robot arm characterized by being arranged. The robot arm according to claim 10,
A robot arm, wherein a drive source for driving the second link is provided on the second link. The robot arm according to claim 10 or 11,
The robot arm, wherein the wiring is a wiring for supplying electric power for driving the driving source. The robot arm according to any one of claims 10 to 12,
A position sensor that detects a relative displacement between the first auxiliary link and the second link is provided at a connecting portion between the first auxiliary link and the second link,
The robot arm, wherein the wiring includes a wiring that transmits a signal from the position sensor. The robot arm according to any one of claims 10 to 13,
The second link is provided with a torque sensor that detects a torque generated in the second link,
The robot arm, wherein the wiring includes a wiring for transmitting a signal from the torque sensor.   A method of manufacturing an article, which uses the robot arm according to any one of claims 1 to 14.

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