Robot and robot system

Abstract

To provide a robot and a robot system possible to suppress detection of excess vibration by an inertia sensor.SOLUTION: A robot includes a base, a first arm, a second arm rotatably connected to the first arm, a shaft on which an end effector is mounted, an inertia sensor installed in the second arm and configured to detect at least one of the angular speed and acceleration speed, a motor unit installed in the second arm and configured to drive the shaft, and a duct connected to the base and the second arm, wherein the second arm has a first member having a first connection section to which the duct is connected and a second member having a second connection section to which a wiring or a piping connected to the end effector is connected and positioned further to the shaft side than the first connection section, and an arm base having an attachment section to which the second member is attached, and the inertia sensor is disposed between the motor unit and the attachment section.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a robot and a robot system. [Background technology]

[0002] The robot described in Patent Document 1 includes a base, a first arm rotatably connected to the base about a first rotation axis, a second arm rotatably connected to the first arm about a second rotation axis parallel to the first rotation axis, and a shaft rotatably connected to the second arm about a third rotation axis parallel to the second rotation axis and movable along the axial direction of the third rotation axis, the shaft having an end effector attached to its lower end. The second arm has a base body and a cover that covers the upper part of the base body. An intermediate body is provided on the base body so as to cover the second rotation axis side of the shaft. Various connectors are provided on the upper part of the intermediate body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-144545 Summary of the Invention [Problem to be solved by the invention]

[0004] In a structure such as that described in Patent Document 1, for example, if an inertial sensor for vibration suppression control is provided on the second arm, there is a risk that the inertial sensor will pick up vibrations from the intermediate body. The vibration components that are unintentionally picked up will then become noise, resulting in a problem of reduced detection accuracy.

[0005] The robot of the present invention comprises: a base; a first arm rotatably connected to the base about a first rotation axis; a second arm connected to the first arm so as to be rotatable about a second rotation axis parallel to the first rotation axis; a shaft connected to the second arm so as to be rotatable about a third rotation axis parallel to the second rotation axis and so as to be movable along the axial direction of the third rotation axis, the shaft having an end effector attached thereto; an inertial sensor installed on the second arm and configured to detect at least one of angular velocity and acceleration; a motor unit installed on the second arm and driving the shaft; a duct connected to the base and the second arm, The second arm is a first member having a first connection portion to which the duct is connected; a second member having a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, The inertial sensor is disposed between the motor unit and the mounting portion.

[0006] The robot system of the present invention includes a robot including: a base; a first arm rotatably connected to the base about a first rotation axis; a second arm rotatably connected to the first arm about a second rotation axis parallel to the first rotation axis; a shaft connected to the second arm rotatably about a third rotation axis parallel to the second rotation axis and movably along the axial direction of the third rotation axis, the shaft having an end effector attached thereto; an inertial sensor attached to the second arm and detecting at least one of angular velocity and acceleration; a motor unit attached to the second arm and driving the shaft; and a duct connected to the base and the second arm. a control device that controls the driving of the robot, The second arm is a first member having a first connection portion to which the duct is connected; a second member provided with a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, The inertial sensor is disposed between the motor unit and the mounting portion.

[0007] The robot of the present invention comprises: a base; a first arm rotatably connected to the base about a first rotation axis; a second arm connected to the first arm so as to be rotatable about a second rotation axis parallel to the first rotation axis; a shaft connected to the second arm so as to be rotatable about a third rotation axis parallel to the second rotation axis and so as to be movable along the axial direction of the third rotation axis, the shaft having an end effector attached thereto; an inertial sensor installed on the second arm and configured to detect at least one of angular velocity and acceleration; a first motor installed on the second arm and outputting a driving force to rotate the shaft around the third rotation axis; a second motor installed on the second arm and outputting a driving force that moves the shaft along the axial direction of the third rotation axis; a first endless belt that transmits the driving force output by the first motor to the shaft; a second endless belt that transmits the driving force output by the second motor to the shaft; a duct connected to the base and the second arm, The second arm is a first member having a first connection portion to which the duct is connected; a second member provided with a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, When viewed along a straight line parallel to the second rotation axis, the first endless belt and the second endless belt intersect with each other, The inertial sensor is disposed between the attachment portion and a position where the first endless belt and the second endless belt intersect. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a robot system according to a first embodiment of the present invention. [Figure 2] 2 is a partial cross-sectional side view illustrating the internal structure of a second arm of the robot shown in FIG. 1. FIG. [Figure 3] FIG. 3 is a view seen from the direction of arrow A in FIG. 2. [Figure 4] FIG. 10 is an enlarged partial cross-sectional view of an arm base of a second arm in a robot system according to a second embodiment of the present invention. [Figure 5] FIG. 10 is an enlarged top view of an arm base of a second arm in a robot according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A robot and a robot system according to the present invention will be described in detail below based on embodiments shown in the accompanying drawings.

[0010] First Embodiment Fig. 1 is a schematic configuration diagram of a robot system according to a first embodiment of the present invention. Fig. 2 is a partial cross-sectional side view for explaining the internal structure of a second arm provided in the robot shown in Fig. 1. Fig. 3 is a view seen from the direction of arrow A in Fig. 2.

[0011] 1 corresponds to the vertical direction, and the upper side in Fig. 1 is also referred to as "upper" and the lower side as "lower." For the robot arm 72, first arm 73, second arm 74, etc., the right side in Fig. 1 is referred to as the "base end" or "base portion," and the left side is referred to as the "tip" or "tip portion."

[0012] In this specification, "vertical" refers not only to a case where the object is perpendicular to the vertical, but also to a case where the object is slightly tilted from the vertical, for example, within ±10°. In this specification, "parallel" refers not only to a case where two objects are parallel to the vertical, but also to a case where the object is slightly tilted from the vertical, for example, within ±10°. In this specification, a "straight line" refers to an imaginary straight line.

[0013] The robot system 1 shown in FIG. 1 includes a robot 7 and a control device 3 that controls the driving of each part of the robot 7.

[0014] The robot 7 in this embodiment is a SCARA robot, and is used for tasks such as holding, transporting, assembling, processing, painting, and inspecting workpieces such as electronic components (hereinafter these are collectively referred to as "tasks"). However, the uses and types of tasks of the robot 7 are not limited to those described above. The robot 7 may also be a ceiling-suspended SCARA robot, in which case the configuration of the robot 7 in this embodiment will be upside down.

[0015] 1, the robot 7 has a base 71 and a robot arm 72 rotatably connected to the base 71. The robot arm 72 has a first arm 73 whose base end is connected to the base 71 and which rotates around a first rotation axis J1 that is vertical to the base 71, and a second arm 74 whose base end is connected to a tip end of the first arm 73 and which rotates around a second rotation axis J2 that is vertical to the first arm 73. The first rotation axis J1 and the second rotation axis J2 are imaginary straight lines.

[0016] A base end of a duct 77 having a tubular outer cover is connected to the base 71, and a tip end of the duct 77 is connected to an upper portion of the second arm 74. The duct 77 is connected to the base 71 and the second arm 74 and guides a first long wire 21 inserted therethrough. The first long wire 21 is inserted through the duct 77. The first long wire 21 is a cable for driving the inertial sensor 5, the motor unit 8, the motor unit 61, and the end effector 76. That is, in this embodiment, the first long wire 21 includes wiring and piping, and is composed of wiring for supplying power to the inertial sensor 5, the motor unit 8, the motor unit 61, and the end effector 76, wiring for controlling the inertial sensor 5, the motor unit 8, the motor unit 61, and the end effector 76, supply piping for supplying a fluid such as compressed air to the end effector 76, etc. It is sufficient that the first long wire 21 includes at least a cable for driving the end effector 76. The first long wire 21 may also be configured to include only one of wiring and piping.

[0017] The base end of the first long wire 21 is connected to, for example, a control device 3 or a power supply unit not shown, and the tip end of the first long wire 21 is connected to predetermined portions of the inertial sensor 5, motor unit 8, motor unit 61, and the second connection part 94 described later.

[0018] The first long wire 21 may be provided as a single wire or as a bundle of multiple wires. Furthermore, the first long wire 21 may be provided with one or more connectors (not shown) midway.

[0019] A shaft 75 is provided at the tip of the second arm 74. The shaft 75 is also referred to as a working shaft. The shaft 75 has a spline nut 751 and a ball screw nut 752 that are coaxially arranged at the tip of the second arm 74, and a spline shaft 753 that is inserted through the spline nut 751 and the ball screw nut 752. The spline shaft 753 is rotatable around a third rotation axis J3 that is its central axis and extends in the vertical direction relative to the second arm 74, and is also movable up and down in the direction along the third rotation axis J3. The third rotation axis J3 is an imaginary straight line.

[0020] An end effector 76 is attached to the lower end of the spline shaft 753. The end effector 76 is detachable from the spline shaft 753, and an end effector suitable for the intended work is selected as appropriate. Examples of types of end effector 76 include a hand, a drill, and a suction head.

[0021] The spline shaft 753 is formed as a long, hollow body extending in the vertical direction, and the second long wire 22 is inserted therein. The second long wire 22 is a cable for driving the end effector 76. That is, in this embodiment, the second long wire 22 includes wiring and piping, and is formed of wiring for supplying power to the end effector 76, wiring for controlling the end effector 76, supply piping for supplying fluid such as compressed air to the end effector 76, etc. Note that the second long wire 22 may be configured to include only either wiring or piping.

[0022] The base end side of the second long wire 22 is connected to a predetermined location of the second connection portion 94, and the tip side of the second long wire 22 extends through the inner cavity of the spline shaft 753 to the end effector 76 and is connected to a predetermined location of the end effector 76.

[0023] The second long wire 22 may be provided as a single wire or as a bundle of multiple wires.

[0024] The robot 7 has a first joint 4K that rotatably connects the base 71 and the first arm 73, and this first joint 4K is equipped with a drive unit 4 that rotates the first arm 73 around a first rotation axis J1 relative to the base 71.

[0025] The robot 7 also has a second joint 6K that rotatably connects the first arm 73 and the second arm 74, and this second joint 6K is equipped with a drive unit 6 that rotates the second arm 74 around a second rotation axis J2 relative to the first arm 73.

[0026] The drive unit 4 has a motor unit 41 and a power transmission mechanism (not shown) that includes, for example, a reducer. The drive unit 6 has a motor unit 61 and a power transmission mechanism (not shown) that includes, for example, a reducer.

[0027] Motor unit 41 generates a driving force that rotates first arm 73 relative to base 71. Motor unit 61 generates a driving force that rotates second arm 74 relative to first arm 73. Motor units 41 and 61 each have a motor (not shown) and an encoder (not shown). There are no particular limitations on the motor units 41 and 61, but it is preferable that they are, for example, servo motors such as AC servo motors or DC servo motors.

[0028] The robot 7 also has a motor unit 8 that drives the shaft 75. The motor unit 8 is provided inside the second arm 74 and has a first motor unit 81 that rotates the spline nut 751 to rotate the spline shaft 753 about the third rotation axis J3, and a second motor unit 82 that rotates the ball screw nut 752 to raise and lower the spline shaft 753 in the direction along the third rotation axis J3, i.e., in the vertical direction.

[0029] The robot 7 also has a first endless belt 83 that transmits the driving force output by the first motor unit 81 to the spline nut 751 of the shaft 75, and a second endless belt 84 that transmits the driving force output by the second motor unit 82 to the ball screw nut 752 of the shaft 75.

[0030] The first motor unit 81 has a first motor 811 and an encoder (not shown). The second motor unit 82 has a second motor 821 and an encoder (not shown). The first motor 811 and the second motor 821 are electrically connected to the control device 3. The control device 3 controls the current supply conditions of the first motor 811 and the second motor 821, such as the current supply pattern, current supply timing, and current supply amount.

[0031] Either or both of the first motor unit 81 and the second motor unit 82 may have a reducer.

[0032] 2, a first endless belt 83 is wound around an output pulley provided on an output shaft 812 of the first motor 811 and an input pulley provided on the spline nut 751. This allows the driving force output by the first motor 811 to be transmitted to the shaft 75, causing the shaft 75 to rotate about the third rotation axis J3.

[0033] A second endless belt 84 is wound around an output pulley provided on an output shaft 822 of the second motor 821 and an input pulley provided on the ball screw nut 752. This allows the driving force output by the second motor 821 to be transmitted to the shaft 75, thereby allowing the shaft 75 to be raised and lowered in the vertical direction.

[0034] The motors of the motor units 41 and 61, the first motor 811, and the second motor 821 are electrically connected to the control device 3. Although not shown, the motors of the motor units 41 and 61, the first motor 811, and the second motor 821 each include a stator, a rotor that rotates inside the stator, and a case that houses these components. The stator is arranged along the inner circumference of the case and has windings such as three-phase windings. The stator generates a magnetic field when current is passed through the windings, for example, when three-phase AC current is passed through the windings. In the motors of the motor units 41 and 61, the first motor 811, and the second motor 821, the current flow pattern, current flow timing, current amount, etc. of the windings of the stators are controlled by the control device 3.

[0035] The motor units 41, 61, the first motor unit 81 and the second motor unit 82 each have a motor driver (not shown), but may be configured not to have a motor driver.

[0036] The motors of the motor units 41 and 61, the first motor 811, and the second motor 821 each rotate in either the forward or reverse direction in response to drive control by the control device 3. The motors of the motor units 41 and 61, the first motor 811, and the second motor 821 each rotate independently.

[0037] The motors of the motor units 41 and 61, the first motor 811 and the second motor 821 may be of the same type and configuration, or may include motors of different types and configurations.

[0038] As shown in Figures 1, 2, and 3, the inertial sensor 5 is installed on the second arm 74 and detects the inertial force of the second arm 74, i.e., at least one of the angular velocity and acceleration, and in this embodiment, both. The inertial sensor 5 may be a single detection element, a detection element mounted on a circuit board, or a module in which these are housed in a housing. If the detection element is mounted on the circuit board, the circuit board may have a function of acquiring the output of the inertial sensor 5 at least periodically and transmitting it to the control device 3.

[0039] In this embodiment, the inertial sensor 5 is installed on the arm base 78 of the second arm 74. In this case, the inertial sensor 5 may be supported or fixed directly to a predetermined portion of the arm base 78, or may be supported or fixed to the arm base 78 via some intermediate member (support member) separate from the arm base 78. When viewed along a line parallel to the second rotation axis J2, the inertial sensor 5 is arranged at a position overlapping a line extending to connect the second rotation axis J2 and the third rotation axis J3, i.e., a line passing through the center of the second arm 74 in the width direction. Note that the inertial sensor 5 may be arranged at a position not overlapping a line connecting the second rotation axis J2 and the third rotation axis J3 when viewed along a line parallel to the second rotation axis J2. Furthermore, although the inertial sensor 5 is installed on the arm base 78, it may also be installed below the arm base 78. Furthermore, although the inertial sensor 5 is installed inside the second arm 74, it may also be installed outside the second arm 74. In addition, "viewed along a straight line parallel to the second rotation axis J2" includes a view from the axial direction of the second rotation axis J2 and a view from the axial direction of the third rotation axis J3. In this embodiment, the straight line parallel to the second rotation axis J2 is a straight line extending in the vertical direction.

[0040] In the configuration shown in Figure 2, the inertial sensor 5 is installed on the upper part of the first protrusion 783 that forms part of the arm base 78, but the inertial sensor 5 may also be installed on the arm base 78 via a separate member (intermediate member) that corresponds to the first protrusion 783.

[0041] A sensor coordinate system is set for the inertial sensor 5. The sensor coordinate system has an origin at an arbitrary point set on the inertial sensor 5, and has three mutually orthogonal axes: an x-axis, a y-axis, and a z-axis.

[0042] In this embodiment, the inertial force detected by the inertial sensor 5 includes six types in total: acceleration along the x-axis, acceleration along the y-axis, acceleration along the z-axis, angular velocity around the x-axis, angular velocity around the y-axis, and angular velocity around the z-axis. That is, the inertial sensor 5 is an IMU (Inertial Measurement Unit) that detects acceleration and angular velocity in three mutually orthogonal axis directions.

[0043] However, the inertial sensor 5 is not limited to this configuration, and may be configured to detect, for example, only acceleration along the x-axis, acceleration along the y-axis, and acceleration along the z-axis, or may be configured to detect only angular velocity around the x-axis, angular velocity around the y-axis, and angular velocity around the z-axis. Also, the inertial sensor 5 may be configured to detect only acceleration along one or two of the x-axis, y-axis, and z-axis, or may be configured to detect only angular velocity around one or two of the x-axis, y-axis, and z-axis.

[0044] In addition to these, the inertial sensor 5 may be configured to detect only angular acceleration around the x-axis, y-axis, and z-axis, or may be configured to detect only angular acceleration in a direction along one or two of the x-axis, y-axis, and z-axis, or may be configured to detect only angular acceleration around one or two of the x-axis, y-axis, and z-axis.

[0045] Although not shown, the control device 3 shown in Fig. 1 has a control unit having at least one CPU (Central Processing Unit), a memory unit that stores various programs executed by the control unit, and a communication unit that transmits and receives signals to and from the robot 7 or external devices. These units are connected to each other so that they can communicate with each other via a bus, for example. In this embodiment, the control device 3 is installed inside the base 71, but it may be installed in another location.

[0046] The control device 3 is also connected to the inertial sensor 5 and acquires signals from the inertial sensor 5 over time. Based on the signals from the inertial sensor 5, the control device 3 controls the operation of one or both of the motor units 41, 61 so as to suppress vibration of the second arm 74. This allows vibration suppression control to be performed on the second arm 74. The control device 3 may also perform learning based on the signals from the inertial sensor 5 and control the operation of the motor units 41, 61 so as to suppress vibration of the second arm 74 based on the learning results.

[0047] Next, the internal structure of the second arm 74 will be described. 1, the second arm 74 has an arm base 78 and a cover 79. Note that the illustration of the cover 79 is omitted in FIG.

[0048] The cover 79 is formed of a housing with an open bottom, and when attached to the arm base 78, it covers the top of the arm base 78 and has the function of protecting the internal components. The cover 79 is formed, for example, from a plate material made of a resin material and molded into a desired three-dimensional shape. It is preferable that this cover 79 has enough elasticity to be slightly deformed when force is applied. The cover 79 may also be formed, for example, from a plate material made of a metal material such as stainless steel or aluminum and molded into a desired three-dimensional shape. The cover 79 may also be a frame-shaped body.

[0049] The arm base 78 is made of a rigid body that functions to support the internal components of the second arm 74 and the shaft 75. Examples of materials that can be used to form the arm base 78 include various metal materials, various resin materials, particularly hard resin materials, and various ceramics, and may also be composite materials that are any combination of these. Among these, examples of metal materials include stainless steel and aluminum.

[0050] The arm base 78 has a long block shape extending in one direction, i.e., the left-right direction in Figures 1 to 3. The form, shape, etc. of the arm base 78 are not limited to those described above, and may be, for example, a plate-like body, a frame-like body, or a combination of these.

[0051] As shown in Figures 2 and 3, the base end of the arm base 78 is provided with an installation portion 781 on which the drive unit 6 is installed, and the tip end of the arm base 78 is provided with an insertion hole 782 through which the shaft 75 is inserted.

[0052] The installation portion 781 is configured as a through hole with the second rotation axis J2 as its central axis. The drive unit 6 is fixed to the inner periphery of the installation portion 781.

[0053] The insertion hole 782 is configured as a through-hole with the third rotation axis J3 as its central axis. A ball screw nut 752 is fixed to the edge of the upper opening of the insertion hole 782.

[0054] In addition to supporting the drive unit 6 and shaft 75 as described above, the arm base 78 also supports a first motor unit 81, a second motor unit 82, an inertial sensor 5, a first stay 91, a second stay 92, and the like.

[0055] 1 to 3, i.e., in the longitudinal direction of the arm base 78, the first motor unit 81 and the second motor unit 82 are installed between the drive unit 6 and the shaft 75. When viewed along a line parallel to the second rotation axis J2 or along the width direction described below, at least a portion of the first motor unit 81 and the second motor unit 82 is located between the inertial sensor 5 and the drive unit 6, that is, installed at a position offset toward the drive unit 6 side relative to the inertial sensor 5. This allows the drive unit 6 to be spaced farther away from the inertial sensor 5, the length of the second arm 74 to be shortened, and the space between the second rotation axis J2 and the third rotation axis J3 to be effectively utilized. In this case, the distance between the rotation center of the first motor unit 81 and the second rotation axis J2 is shorter than the distance between the rotation center of the first motor unit 81 and the third rotation axis J3, and the distance between the rotation center of the second motor unit 82 and the second rotation axis J2 is shorter than the distance between the rotation center of the second motor unit 82 and the third rotation axis J3. Also, as shown in FIG. 3 , the first motor unit 81 and the second motor unit 82 are arranged side by side along the width direction of the arm base 78. That is, when viewed from the width direction, at least a portion of the first motor unit 81 overlaps with at least a portion of the second motor unit 82. The width direction is the direction that intersects with the line connecting the second rotation axis J2 and the third rotation axis J3 when viewed along a line parallel to the second rotation axis J2. In this embodiment, the width direction is the direction that is perpendicular to the line connecting the second rotation axis J2 and the third rotation axis J3.

[0056] In FIG. 2, the first motor unit 81 and the second motor unit 82 are shown shifted along the longitudinal direction of the arm base 78 in order to make them easier to see.

[0057] The first motor unit 81 is fixed to the arm base 78 via a fixing member (not shown) with its output shaft 812 protruding downward. The fixing member of the first motor unit 81 is attached to the case of the first motor 811. The second motor unit 82 is fixed to the arm base 78 via a fixing member (not shown) with its output shaft 822 protruding downward. The fixing member of the second motor unit 82 is attached to the case of the second motor 821. The lower end of the output shaft 812 of the first motor unit 81, i.e., the output pulley of the output shaft 812, is located higher than the lower end of the output shaft 822 of the second motor unit 82, i.e., the output pulley of the output shaft 822. As a result, as shown in FIG. 2, the first endless belt 83 and the second endless belt 84 that are wound around them are spaced apart in the vertical direction, preventing them from interfering with each other.

[0058] In the longitudinal direction of the arm base 78, the lower end of the first stay 91 is located closer to the base end (right side in FIG. 2 ) than the installation portion 781, i.e., on the opposite side of the shaft 75 from the installation portion 781 on which the drive unit 6 is installed. The first stay 91 is a first member having a first connecting portion 93. The first stay 91 has a first portion 911 standing in the vertical direction and a second portion 912 extending horizontally from the upper end of the first portion 911 toward the tip side. The first portion 911 and the second portion 912 each have a flat plate shape. However, this configuration is not limited thereto, and the first portion 911 and the second portion 912 may have other shapes, such as a rod shape. Alternatively, a configuration may be adopted in which a plurality of first portions 911 are provided and the second portion 912 is supported by the plurality of first portions 911.

[0059] A first connection portion 93 to which the duct 77 is connected is provided on the upper surface side of the second portion 912. When viewed along a line parallel to the second rotation axis J2, the first connection portion 93 overlaps with the second rotation axis J2. In other words, the first connection portion 93 is located on a line extending along the second rotation axis J2. The first connection portion 93 may be a connector to which the duct 77 can be detachably attached, a fixing portion that fixes the duct 77, or the like.

[0060] Furthermore, a first long wire 21 protruding downward from the underside of the second portion 912, i.e., wiring for driving the motor unit 61 of the drive unit 6, extends from the first connection portion 93. Further, first long wires 21 protruding from the underside of the second portion 912 toward the tip end, i.e., wiring for driving the inertial sensor 5, the first motor unit 81, and the second motor unit 82, extend from the first connection portion 93. A locking member (not shown) is provided on the tip end of the first portion 911, and the first long wire 21 is locked by the locking member. Note that the locking member may be provided on the second portion 912, or may not be provided on either the first portion 911 or the second portion 912.

[0061] The second stay 92 is disposed between the installation portion 781 and the insertion hole 782 in the longitudinal direction of the arm base 78, and is located offset toward the insertion hole 782. The second stay 92 is a second member having a second connection portion 94 and located closer to the shaft 75 than the first connection portion 93. The second stay 92 has a first portion 921 erected in the vertical direction and a second portion 922 extending horizontally from the upper end of the first portion 921 toward the base end. The first portion 921 and the second portion 922 each have a flat plate shape. However, this configuration is not limited thereto, and the first portion 921 and the second portion 922 may have other shapes, such as a rod shape. Alternatively, the arm base 78 may have a plurality of first portions 921, and the second portion 922 may be supported by the plurality of first portions 921.

[0062] Furthermore, the second portion 922 extends toward the base end and is located above the inertial sensor 5. That is, the second portion 922 has a portion that overlaps with the inertial sensor 5. This allows the length of the second arm 74 to be shortened and makes effective use of the space between the second rotation axis J2 and the third rotation axis J3.

[0063] The second portion 922 is provided with a second connection portion 94 to which the second long wire 22 is connected. The second connection portion 94 may be a connector to which the second long wire 22 can be detachably attached, or a fixing portion that fixes the base end (terminal portion) of the second long wire 22 with, for example, a screw or soldering. The second long wire 22 is routed to the upper portion of the spline shaft 753 through a through-hole (not shown) provided in the upper portion of the cover 79.

[0064] The first long wire 21 is connected to the second connecting portion 94 from the underside of the second portion 922. A locking member (not shown) is provided on the base end side of the first portion 921, and the first long wire 21 is locked by the locking member. The locking member may be provided on the tip side of the first portion 921 or on the second portion 922.

[0065] The arm base 78 also has a first protrusion 783 and a second protrusion 784. The upper ends of the first protrusion 783 and the second protrusion 784 are located higher than the first endless belt 83 and the second endless belt 84, respectively. The first protrusion 783 and the second protrusion 784 are provided so as not to come into contact with the first endless belt 83 and the second endless belt 84.

[0066] In this embodiment, the first protrusion 783 and the second protrusion 784 are each convex portions that protrude upward from the arm base 78. The convex portions are trapezoidal, i.e., have a planar upper portion, and in this embodiment, are block-shaped, particularly prismatic. However, without being limited thereto, the convex portions may have other shapes, such as a truncated pyramid shape, a columnar shape, a truncated cone shape, a cylindrical shape, a desired bent plate shape, a frame shape, or the like, and may be solid or hollow.

[0067] The first protrusion 783 and the second protrusion 784 are provided between the motor unit 8 and the shaft 75 in the longitudinal direction of the arm base 78. That is, the first protrusion 783 and the second protrusion 784 are provided between the motor unit 8 and the shaft 75 when viewed along a straight line parallel to the second rotation axis J2 or when viewed along the width direction. The first protrusion 783 and the second protrusion 784 are arranged spaced apart from each other and offset in the direction in which the second rotation axis J2 and the third rotation axis J3 are aligned. The positional relationship between the first protrusion 783 and the second protrusion 784 is such that the first protrusion 783 is located on the motor unit 8 side (base end side), and the second protrusion 784 is located on the shaft 75 side (tip end side).

[0068] The inertial sensor 5 is installed on the upper part of the first protrusion 783. The lower end part of the second stay 92 is installed on the upper part of the second protrusion 784. The inertial sensor 5 and the second stay 92 are each installed on the protrusion and fixed to the protrusion, for example, using one or more fixing members such as screws. The upper surface of the second protrusion 784 is the mounting part 100 to which the second stay 92 is attached. The mounting part 100 is located between the inertial sensor 5 and the shaft 75 when viewed along a straight line parallel to the second rotation axis J2 or when viewed along the width direction.

[0069] The first protrusion 783 and the second protrusion 784 may each be composed of a plurality of protrusions. Supporting the inertial sensor 5 or the second stay 92 by a plurality of protrusions makes them less susceptible to vibration, and also makes it easier to arrange and shape the protrusions so as not to interfere with an endless belt or the like. In this case, a fixing member such as a screw may be used for each protrusion. The plurality of protrusions may each have a different configuration. The protrusions may be separate members from the arm base 78. For example, the protrusions may be rod-shaped members separate from the arm base 78, and the first protrusion 783 and the second protrusion 784 may each be composed of a plurality of rod-shaped members spaced apart from each other, like legs. The first protrusion 783 and the second protrusion 784 may also have different configurations. For example, the first protrusion 783 may have a configuration including a plurality of cylindrical protrusions, and the second protrusion 784 may have a configuration including only one rectangular pillar-shaped protrusion. The first protrusion 783 and the second protrusion 784 may be omitted. In this case, the inertial sensor 5 and the second stay 92 are fixed to the arm base 78 using fixing members such as screws. At this time, the location where the second stay 92 is attached by the fixing members such as screws is the attachment portion 100.

[0070] Furthermore, first protrusion 783 and second protrusion 784 may be connected. That is, instead of first protrusion 783 and second protrusion 784, a configuration may be provided with a single protrusion, or a connecting member may be provided that connects first protrusion 783 and second protrusion 784. In either case, the protrusions are less likely to vibrate, and the effects of the present invention can be significantly achieved.

[0071] 3, when viewed along a straight line parallel to the second rotation axis J2, the first endless belt 83 and the second endless belt 84 partially intersect, and the inertial sensor 5 is installed inside the first endless belt 83 and the second endless belt 84 when viewed along a straight line parallel to the second rotation axis J2, and closer to the mounting portion 100 (tip side) than a position P1 where the first endless belt 83 and the second endless belt 84 intersect (intersection position). This allows the inertial sensor 5 to be located further away from the first motor unit 81 and the second motor unit 82, which may be a source of vibrations undesirable for vibration control, i.e., unnecessary vibrations.

[0072] The arm base 78 also has a through hole 785 that penetrates in the vertical direction, i.e., in the axial direction of the second rotation axis J2. In this embodiment, the through hole 785 is provided in a position between the first protrusion 783 and the second protrusion 784 in the longitudinal direction of the arm base 78, i.e., a position between the inertial sensor 5 and the mounting portion 100. In other words, the through hole 785 is provided between the inertial sensor 5 and the mounting portion 100 when viewed along a straight line parallel to the second rotation axis J2 or when viewed along the width direction. However, the position where the through hole 785 is formed is not limited thereto. The through hole 785 may be formed, for example, closer to the base end of the arm base 78 than the first protrusion 783 or closer to the tip end of the second protrusion 784. Furthermore, a plurality of through holes 785 may be formed in at least one of these positions.

[0073] Such through-holes 785 have a function of dissipating heat generated by, for example, the drive unit 6, motor unit 8, inertial sensor 5, etc. and accumulated inside the second arm 74 to the outside, i.e., a heat dissipation function. This prevents an excessive temperature rise inside the second arm 74, and in particular, dissipates heat generated by the inertial sensor 5 to the outside, preventing a temperature rise in the inertial sensor 5. This maintains high detection accuracy of the inertial sensor 5, i.e., allows sufficient detection of vibrations that are originally intended to be detected, and enables the aforementioned vibration suppression control to be performed more accurately. As a result, the robot 7 can operate more stably.

[0074] Furthermore, when the through hole 785 is formed between the inertial sensor 5 and the mounting portion 100, the through hole 785 makes it difficult for vibrations transmitted from the second stay 92 to the arm base 78 through the mounting portion 100 to be transmitted directly to the inertial sensor 5, which is advantageous for suppressing vibrations of the inertial sensor 5.

[0075] In this way, the arm base 78 is provided with a through-hole 785 that penetrates in the axial direction of the second rotation axis J2 between the inertial sensor 5 and the mounting portion 100. This allows heat inside the second arm 74, particularly heat generated by the inertial sensor 5, to be dissipated to the outside. Furthermore, the through-hole 785 makes it difficult for vibrations transmitted from the second stay 92 through the mounting portion 100 to be transmitted to the inertial sensor 5. This maintains high detection accuracy of the inertial sensor 5, allowing for more accurate vibration suppression control of the robot arm 72. As a result, the robot 7 can operate more stably.

[0076] Note that through-hole 785 may be omitted. Furthermore, one or more through-holes 785 may be provided at other locations on arm base 78 of second arm 74 or at any other location, for example, in cover 79. For example, if through-hole 785 is provided between insertion hole 782 and second protruding portion 784 or between installation portion 781 and first protruding portion 783 in addition to the locations shown in FIG. 2 , the heat dissipation effect described above will be further improved.

[0077] As described above, the inertial sensor 5 detects the inertial force of the second arm 74 to perform vibration suppression control of the robot arm 72. However, the inertial sensor 5 also picks up unnecessary vibration components, i.e., vibration components undesirable for vibration suppression control (hereinafter referred to as "unwanted vibrations" or "unwanted vibration components"), such as vibrations of the shaft 75, the mounting portion 100, the second stay 92, the motor unit 8, the drive unit 6, and other noise. The inclusion of these unnecessary vibration components reduces the accuracy of vibration suppression control. Therefore, the inertial sensor 5 must be positioned so as to minimize the detection of unnecessary vibration components. While this issue has not been adequately addressed in the past, the present invention solves the above issue by configuring the positional relationships of the various components in the longitudinal direction of the second arm 74 as follows. This will be explained below.

[0078] 2 and 3 , in the robot 7, the mounting portion 100, the inertial sensor 5, and the motor unit 8 are arranged in this order in the longitudinal direction of the second arm 74, spaced apart from one another, from the third rotation axis J3 toward the second rotation axis J2. That is, the shaft 75, the mounting portion 100, the motor unit 8, and the drive unit 6, which are sources of unnecessary vibrations, are arranged at a distance from the inertial sensor 5, thereby preventing the inertial sensor 5 from detecting unnecessary vibration components. In particular, the shaft 75 and the drive unit 6, which generate particularly large unnecessary vibrations, can be located farther from the inertial sensor 5 than the second stay 92 and the motor unit 8, which generate relatively small vibrations, thereby more significantly preventing the inertial sensor 5 from detecting unnecessary vibrations.

[0079] Due to the synergistic effect of these factors, the above-described arrangement significantly reduces the detection of unnecessary vibrations by the inertial sensor 5, enabling more accurate and precise vibration control of the robot arm 72. As a result, the accuracy of the work performed by the robot 7 can be improved. When the motor units 8 are the first motor unit 81 and the second motor unit 82, the inertial sensor 5 may be disposed, for example, between the midpoint between the rotation centers of the first motor unit 81 and the second motor unit 82 and the mounting portion 100, or between the outer shape or rotation center of the first motor unit 81 and the mounting portion 100, and between the outer shape or rotation center of the second motor unit 82 and the mounting portion 100. The motor unit 8 may include only one of the first motor unit 81 and the second motor unit 82. In this case, the inertial sensor 5 may be disposed between the outer shape or rotation center of either the first motor unit 81 or the second motor unit 82 and the mounting portion 100.

[0080] Furthermore, in this embodiment, unlike the conventional configuration, the first stay 91 and the second stay 92 are installed independently of each other, thereby improving the flexibility of installing components such as wiring in the space between the first stay 91 and the second stay 92. For example, it is possible to reduce the height of either or both of the first stay 91 and the second stay 92. This allows the second arm 74 to be made smaller, shorter, and lighter, thereby reducing the size of the robot 7. In particular, the smaller, shorter, and lighter second arm 74 contributes to reducing the inertial weight of the second arm 74, thereby increasing the operating speed of the robot arm 72 and improving the efficiency of the work performed by the robot 7. Note that, in this configuration in which the first stay 91 and the second stay 92 are installed independently of each other, the second stay 92, which supports the weight of the second connection portion 94, is prone to vibration. In particular, in the case of a cantilever structure having only one first portion 921 as in this embodiment, or when the second arm 74 is long in the longitudinal direction, the vibration of the second stay 92 becomes large. However, by positioning the mounting portion 100 of the second stay 92 between the inertial sensor 5 and the shaft 75, i.e., by positioning it closer to the shaft 75 than the inertial sensor 5, the shaft 75 is spaced farther from the inertial sensor 5, the length of the second arm 74 can be shortened, and the space between the second rotation axis J2 and the third rotation axis J3 can be effectively utilized. Furthermore, the second connection portion 94 of the second stay 92 can be positioned closer to the shaft 75. By shortening the length of the second long wire 22, the second long wire 22 becomes less likely to vibrate, thereby suppressing vibration transmitted from the second long wire 22 to the inertial sensor 5 via the second stay 92.

[0081] As described above, the robot 7 includes the base 71, the first arm 73 connected to the base 71 so as to be rotatable about the first rotation axis J1, the second arm 74 connected to the first arm 73 so as to be rotatable about the second rotation axis J2 parallel to the first rotation axis J1, the shaft 75 connected to the second arm 74 so as to be rotatable about the third rotation axis J3 parallel to the second rotation axis J2 and to be movable along the axial direction of the third rotation axis J3, and having the end effector 76 attached thereto, the inertial sensor 5 installed on the second arm 74 and detecting at least one of angular velocity and acceleration, and the shaft 75 installed on the second arm 74 so as to be rotatable about the third rotation axis J3 parallel to the second rotation axis J2 and movable along the axial direction of the third rotation axis J3. The robot arm 74 includes a motor unit 8 that drives a spool 75 and a duct 77 connected to the base 71 and a second arm 74. The second arm 74 includes a first stay 91 that is a first member having a first connection portion 93 to which the duct 77 is connected, a second connection portion 94 to which a second long wire 22 including one of wiring and piping connected to the end effector 76 is connected, a second stay 92 that is a second member located closer to the shaft 75 than the first connection portion 93, and an arm base 78 that has a mounting portion 100 to which the second stay 92 is attached. The inertial sensor 5 is disposed between the motor unit 8 and the mounting portion 100. This effectively prevents the inertial sensor 5 from detecting unnecessary vibrations. As a result, various controls using the detection value of the inertial sensor 5, such as vibration suppression control of the robot arm 72, can be more appropriately performed.

[0082] The robot system 1 includes a base 71, a first arm 73 rotatably connected to the base 71 about a first rotation axis J1, a second arm 74 rotatably connected to the first arm 73 about a second rotation axis J2 parallel to the first rotation axis J1, a shaft 75 connected to the second arm 74 about a third rotation axis J3 parallel to the second rotation axis J2 and movably along the axial direction of the third rotation axis J3, and having an end effector 76 attached thereto, an inertial sensor 5 installed on the second arm 74 and detecting at least one of angular velocity and acceleration, and a motor unit 8 installed on the second arm 74 and driving the shaft 75. The robot 7 includes a base 71 and a duct 77 connected to a second arm 74, and a control device 3 that controls the driving of the robot 7. The second arm 74 includes a first stay 91 that is a first member having a first connection portion 93 to which the duct 77 is connected, a second stay 92 that is a second member located closer to the shaft 75 than the first connection portion 93 and that is provided with a second connection portion 94 to which a second long wire 22 including one of wiring and piping connected to an end effector 76 is connected, and an arm base 78 that has a mounting portion 100 to which the second stay 92 is attached, and the inertial sensor 5 is disposed between the motor unit 8 and the mounting portion 100. This effectively prevents the inertial sensor 5 from detecting unnecessary vibrations. As a result, various controls using the detection value of the inertial sensor 5, such as vibration suppression control of the robot arm 72, can be more appropriately performed.

[0083] In this embodiment, the case where the first stay 91 is installed has been described, but the present invention is not limited to this, and the first stay 91 may be omitted. In this case, the first connection portion 93 to which the duct 77 is connected is installed, for example, on the upper part of the cover 79. The cover 79 is the first member to which the duct 77 is connected.

[0084] The motor unit 8 includes a first motor unit 81 and a second motor unit 82. The second arm 74 includes a first endless belt 83 that transmits the driving force output by the first motor unit 81 to the shaft 75 and a second endless belt 84 that transmits the driving force output by the second motor unit 82 to the shaft 75. The arm base 78 includes a first protrusion 783 that protrudes upward beyond the first endless belt 83 and the second endless belt 84. The inertial sensor 5 is installed on the upper part of the first protrusion 783. This prevents the inertial sensor 5 from interfering with the first endless belt 83 and the second endless belt 84. As a result, the inertial sensor 5 is prevented from detecting unnecessary vibrations due to contact or interference with the first endless belt 83 and the second endless belt 84. Furthermore, the shaft 75 is driven smoothly and satisfactorily, i.e., the spline shaft 753 rotates and moves up and down.

[0085] Furthermore, the inertial sensor 5 can be located away from the shaft 75, the second stay 92, and the motor unit 8, which may be sources of unwanted vibrations. This makes it possible to more effectively prevent the inertial sensor 5 from detecting unwanted vibrations.

[0086] The upper portion of the first protrusion 783 may be at the same height as the first endless belt 83 or the second endless belt 84, or may be located at a position lower than the first endless belt 83 and the second endless belt 84. Moreover, the first protrusion 783 may be omitted.

[0087] The arm base 78 has a second protruding portion 784 that protrudes upward beyond the first endless belt 83 and the second endless belt 84, and the mounting portion 100 is disposed above the second protruding portion 784. This prevents the second stay 92 from interfering with the first endless belt 83 and the second endless belt 84, while also positioning the second stay 92, which could be a source of unwanted vibrations, farther away from the inertial sensor 5. As a result, it is possible to more significantly suppress the inertial sensor 5 from detecting unwanted vibrations, and also to drive the shaft 75, i.e., the rotation and vertical movement of the spline shaft 753, smoothly and satisfactorily.

[0088] The upper portion of the second protrusion 784 may be at the same height as the first endless belt 83 or the second endless belt 84, or may be located at a position lower than the first endless belt 83 and the second endless belt 84. Moreover, the second protrusion 784 may be omitted.

[0089] When viewed along a straight line parallel to the second rotation axis J2, the first endless belt 83 and the second endless belt 84 intersect, and the inertial sensor 5 is installed closer to the mounting portion 100 than the position P1 where the first endless belt 83 and the second endless belt 84 intersect. This allows the inertial sensor 5 to be further away from the first motor unit 81 and the second motor unit 82, which may be sources of unwanted vibrations. As a result, the inertial sensor 5 can be more significantly prevented from detecting unwanted vibrations.

[0090] The inertial sensor 5 may be installed closer to the first motor unit 81 and the second motor unit 82 than the position P1.

[0091] The distance between the second rotation axis J2 and the third rotation axis J3 is preferably 375 mm to 1000 mm, and more preferably 425 mm to 600 mm. When the distance between the second rotation axis J2 and the third rotation axis J3 is within this range, the second arm 74 is relatively long and prone to vibration, thereby achieving a more pronounced effect of the present invention.

[0092] In the present invention, the distance between the second rotation axis J2 and the third rotation axis J3 is not particularly limited, and may be outside the above range.

[0093] When viewed along a line parallel to the second rotation axis J2, the inertial sensor 5 has a portion that overlaps with the second connection portion 94. This allows the length of the second arm 74 to be shortened, reducing the inertial weight of the second arm 74. As a result, the operating speed of the robot arm 72 can be increased, improving the efficiency of work performed by the robot 7. In addition, the space between the second rotation axis J2 and the third rotation axis J3 can be used effectively.

[0094] When viewed along a straight line parallel to the second rotation axis J2, the inertial sensor 5 may or may not entirely overlap the second connection portion 94.

[0095] Second Embodiment FIG. 4 is an enlarged partial cross-sectional view of an arm base of a second arm in a robot system according to a second embodiment of the present invention.

[0096] Hereinafter, a second embodiment of the robot and robot system of the present invention will be described with reference to FIG. 4. The following description will focus on the differences from the first embodiment, and a description of similar points will be omitted.

[0097] 4, the inertial sensor 5 is installed across the first protrusion 783 and the second protrusion 784. That is, the base end (the end on the second rotation axis J2 side) of the inertial sensor 5 is fixed to the top of the first protrusion 783, and the tip end (the end on the third rotation axis J3 side) of the inertial sensor 5 is fixed to the top of the second protrusion 784. With this configuration, the length of the second arm 74 can be shortened and the space between the second rotation axis J2 and the third rotation axis J3 can be used effectively.

[0098] In this way, the inertial sensor 5 is installed across the first protrusion 783 and the second protrusion 784. This allows the length of the second arm 74 to be shortened, reducing the inertial weight of the second arm 74. As a result, the operating speed of the robot arm 72 can be increased, and the efficiency of the work performed by the robot 7 can be improved. In addition, the space between the second rotation axis J2 and the third rotation axis J3 can be used effectively.

[0099] Third Embodiment FIG. 5 is an enlarged top view of an arm base of a second arm in a robot according to a third embodiment of the present invention.

[0100] Hereinafter, a third embodiment of the robot and robot system of the present invention will be described with reference to FIG. 5. The following description will focus on the differences from the first embodiment, and a description of similar points will be omitted.

[0101] As shown in FIG. 5 , when viewed along a line parallel to the second rotation axis J2, the first endless belt 83 and the second endless belt 84 intersect at position P1. The inertial sensor 5 is spaced apart from the first motor 811, the second motor 821, and the mounting unit 100. The inertial sensor 5 is disposed between the mounting unit 100 and position P1, where the first endless belt 83 and the second endless belt 84 intersect, in the longitudinal direction of the arm base 78. This configuration allows the inertial sensor 5 to be spaced apart from the shaft 75, the mounting unit 100, the first motor 811, and the second motor 821, which may be sources of unwanted vibration. This prevents the inertial sensor 5 from detecting unwanted vibration.

[0102] Furthermore, since the inertial sensor 5 is installed between the position P1 where the first endless belt 83 and the second endless belt 84 intersect and the mounting portion 100, the inertial sensor 5 can be placed away from the first motor 811 and the second motor 821, which generate particularly large unnecessary vibrations, and the inertial sensor 5 can be more significantly prevented from detecting unnecessary vibrations.

[0103] The above synergistic effect can more effectively prevent the inertial sensor 5 from detecting unnecessary vibrations, enabling more accurate and precise vibration suppression control of the robot arm 72. As a result, the accuracy of the work performed by the robot 7 can be improved.

[0104] The robot 7 includes a base 71, a first arm 73 connected to the base 71 so as to be rotatable around a first rotation axis J1, a second arm 74 connected to the first arm 73 so as to be rotatable around a second rotation axis J2 parallel to the first rotation axis J1, a shaft 75 connected to the second arm 74 so as to be rotatable around a third rotation axis J3 parallel to the second rotation axis J2 and so as to be movable along the axial direction of the third rotation axis J3, and to which an end effector 76 is attached, an inertial sensor 5 installed on the second arm 74 and detecting at least one of angular velocity and acceleration, a first motor 811 installed on the second arm 74 and outputting a driving force to rotate the shaft 75 around the third rotation axis J3, a second motor 821 installed on the second arm 74 and outputting a driving force to move the shaft 75 along the axial direction of the third rotation axis J3, and a first end rail 831 for transmitting the driving force output by the first motor 811 to the shaft 75. The second arm 74 includes a first stay 91 as a first member having a first connection portion 93 to which the duct 77 is connected, a second stay 92 as a second member located closer to the shaft 75 than the first connection portion 93 and having a second long line 22 including one of the wiring and piping connected to the end effector 76 connected to the second stay 92, and an arm base 78 having an attachment portion 100 to which the second stay 92 is attached. When viewed along a straight line parallel to the second rotation axis J2, the first endless belt 83 and the second endless belt 84 intersect with each other, and the inertial sensor 5 is disposed between the attachment portion 100 and the position P1 where the first endless belt 83 and the second endless belt 84 intersect. This effectively prevents the inertial sensor 5 from detecting unnecessary vibrations. As a result, various controls using the detection values ​​of the inertial sensor 5, such as vibration suppression control of the robot arm 72, can be performed more appropriately.

[0105] In this embodiment, the shaft 75 may be arranged adjacent to the second stay 92 (mounting portion 100), different from the illustrated configuration, or may be arranged between the second stay 92 (mounting portion 100) and the inertial sensor 5. The shaft 75 and the second stay 92 (mounting portion 100) may also be arranged on the second protruding portion 784.

[0106] While the robot and robot system of the present invention have been described above based on the illustrated embodiments, the present invention is not limited to these, and the configuration of each part in the robot and robot system can be replaced with any configuration having a similar function. Furthermore, any other components may be added to the robot and robot system.

[0107] The robot may also have a locking member for locking the second long wire. The locking member can be fixed to the second stay, the inner wall of the arm base, or the like.

[0108] The robot may also have a plate that supports the spline shaft, in which case the inertial sensor is disposed spaced apart from the spline shaft. [Explanation of symbols]

[0109] 1...Robot system, 3...Control device, 4...Drive unit, 4K...First joint unit, 5...Inertial sensor, 6...Drive unit, 6K...Second joint unit, 7...Robot, 8...Motor unit, 21...First long wire, 22...Second long wire, 41...Motor unit, 61...Motor unit, 71...Base, 72...Robot arm, 73...First arm, 74...Second arm, 75...Shaft, 76...End effector, 77...Duct, 78...Arm base, 79...Cover, 81...First motor unit, 82...Second motor unit, 83...First endless belt, 84...Second end effector Dress belt, 91...first stay, 92...second stay, 93...first connection portion, 94...second connection portion, 100...mounting portion, 751...spline nut, 752...ball screw nut, 753...spline shaft, 781...installation portion, 782...insertion hole, 783...first protrusion, 784...second protrusion, 785...through hole, 811...first motor, 812...output shaft, 821...second motor, 822...output shaft, 911...first part, 912...second part, 921...first part, 922...second part, A...arrow, J1...first rotation axis, J2...second rotation axis, J3...third rotation axis, P1...position

Claims

1. The base and a first arm rotatably connected to the base about a first rotation axis; a second arm connected to the first arm so as to be rotatable about a second rotation axis parallel to the first rotation axis; a shaft connected to the second arm so as to be rotatable about a third rotation axis parallel to the second rotation axis and so as to be movable along the axial direction of the third rotation axis, the shaft having an end effector attached thereto; an inertial sensor installed on the second arm and configured to detect at least one of angular velocity and acceleration; a motor unit installed on the second arm and driving the shaft; a duct connected to the base and the second arm, The second arm is a first member having a first connection portion to which the duct is connected; a second member having a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, The robot is characterized in that the inertial sensor is disposed between the motor unit and the mounting portion.

2. The motor unit includes a first motor unit and a second motor unit, the second arm has a first endless belt that transmits the driving force output by the first motor unit to the shaft and a second endless belt that transmits the driving force output by the second motor unit to the shaft, 2. The robot according to claim 1, wherein the arm base has a first protrusion that protrudes upward above the first endless belt and the second endless belt, and the inertial sensor is installed on an upper portion of the first protrusion.

3. the arm base has a second protruding portion that protrudes upward beyond the first endless belt and the second endless belt, The robot according to claim 2 , wherein the attachment portion is disposed on an upper portion of the second protrusion.

4. The robot according to claim 3 , wherein the inertial sensor is installed across the first protrusion and the second protrusion.

5. When viewed along a straight line parallel to the second rotation axis, the first endless belt and the second endless belt intersect with each other, 5. The robot according to claim 2, wherein the inertial sensor is installed closer to the attachment portion than a position where the first endless belt and the second endless belt intersect.

6. 5. The robot according to claim 1, wherein the second rotation axis and the third rotation axis are spaced apart from each other by a distance of 375 mm or more.

7. The robot according to claim 1 , wherein the inertial sensor has a portion that overlaps with the second connection portion when viewed along a straight line parallel to the second rotation axis.

8. The robot according to claim 1 , wherein the arm base is provided with a through-hole that penetrates in the axial direction of the second rotation shaft between the inertial sensor and the mounting portion.

9. a first arm rotatably connected to the base about a first rotation axis; a second arm rotatably connected to the first arm about a second rotation axis parallel to the first rotation axis; a shaft to which an end effector is attached, the shaft being connected to the second arm about a third rotation axis parallel to the second rotation axis and movably along the axial direction of the third rotation axis; an inertial sensor attached to the second arm and detecting at least one of angular velocity and acceleration; a motor unit attached to the second arm and driving the shaft; and a duct connected to the base and the second arm. a control device that controls the driving of the robot, The second arm is a first member having a first connection portion to which the duct is connected; a second member provided with a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, The robot system is characterized in that the inertial sensor is disposed between the motor unit and the mounting portion.

10. The base and a first arm rotatably connected to the base about a first rotation axis; a second arm connected to the first arm so as to be rotatable about a second rotation axis parallel to the first rotation axis; a shaft connected to the second arm so as to be rotatable about a third rotation axis parallel to the second rotation axis and so as to be movable along the axial direction of the third rotation axis, the shaft having an end effector attached thereto; an inertial sensor installed on the second arm and configured to detect at least one of angular velocity and acceleration; a first motor installed on the second arm and configured to output a driving force for rotating the shaft around the third rotation axis; a second motor installed on the second arm and configured to output a driving force for moving the shaft along the axial direction of the third rotation axis; a first endless belt that transmits a driving force output by the first motor to the shaft; a second endless belt that transmits the driving force output by the second motor to the shaft; a duct connected to the base and the second arm, The second arm is a first member having a first connection portion to which the duct is connected; a second member provided with a second connection portion to which wiring or piping connected to the end effector is connected, the second member being located closer to the shaft than the first connection portion; an arm base having an attachment portion to which the second member is attached, When viewed along a straight line parallel to the second rotation axis, the first endless belt and the second endless belt intersect with each other, The robot is characterized in that the inertial sensor is disposed between the attachment portion and a position where the first endless belt and the second endless belt intersect.

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