Robotic arm and robotic system

Abstract

A robot system and a robot arm capable of suppressing sway of wiring led into an interior. The robot arm is characterized by including: a first member; and a second member that is translated along an axis of the first member or rotated about the axis, the first member including: a base; a drive section that generates a drive force; a joint section that has a driven pulley and that transmits the drive force to the second member; a belt that transmits the drive force generated by the drive section to the driven pulley; a sensor that is disposed at a position overlapping with an area surrounded by the driven pulley and the belt when viewed in a direction along the axis and that detects vibration; wiring that is led into the area and that is connected to the sensor; and a support member that is disposed in the area and that supports the wiring.

Description

Technical Field

[0001] This invention relates to robotic arms and robot systems. Background Technology

[0002] With rising labor costs and a shortage of manpower, various robots are being introduced into manufacturing sites. These robots are equipped with robotic arms capable of various movements, automating tasks that have traditionally been performed by human hands.

[0003] For example, Patent Document 1 discloses a SCARA-type robot having a main body and a horizontally articulated arm connected to the main body. The horizontally articulated arm consists of a first arm and a second arm. The base end of the first arm is rotatably connected to the main body via a vertically extending rotation axis. The base end of the second arm is rotatably connected to the front end of the first arm via another vertically extending rotation axis. Furthermore, the front end of the second arm is provided with a working shaft composed of a ball-splined shaft, a mechanism for axial movement and rotation of the working shaft around the axis, a Z-axis motor for axially driving the working shaft, and an R-axis motor for rotating the working shaft around the axis. The driving force is transmitted between the Z-axis motor and the moving mechanism via pulleys, timing belts, etc. Similarly, the driving force is transmitted between the R-axis motor and the rotating mechanism via pulleys, timing belts, etc. This transmission of driving force enables the working shaft to move or rotate and operates a chuck component mounted on the working shaft.

[0004] In recent years, the demand for increased robot sophistication has led to a greater need to integrate various functional components into robotic arms. These functional components require power lines and communication cables to connect to the robot's main body. These cables are routed inside the robotic arm to prevent breakage during contact with objects. Other functional components include sensors that detect the robotic arm's movement. High performance is often achieved by mounting these sensors and other functional components at the front end of the robotic arm. Therefore, the wiring is routed longitudinally from the base of the robotic arm to the front end.

[0005] Patent document 1: Japanese Patent Application Publication No. 7-116974.

[0006] However, the robotic arm contains drive force transmission components such as timing belts. If the wiring of sensors, etc., comes into contact with these drive force transmission components, it can lead to wire breakage or poor connection. In particular, if the wiring is not fixed in place, it can easily come into contact with the timing belt, etc., as it sways with the movement of the robotic arm. Therefore, realizing a robotic arm that fixes the wiring inside the robotic arm to suppress the swaying of the sensor wiring, etc., has become a technical problem. Summary of the Invention

[0007] The robotic arm involved in the application examples of this invention is characterized by having:

[0008] First component; and

[0009] The second component translates along or rotates about the axis located on the first component.

[0010] The first component has:

[0011] bottom;

[0012] The drive unit generates driving force;

[0013] The joint has a driven pulley and transmits the driving force to the second component;

[0014] The belt transmits the driving force generated by the drive unit to the driven pulley;

[0015] The sensor, when viewed from above along the axis, is positioned at a location overlapping the area surrounded by the driven pulley and the belt, and detects vibrations;

[0016] Wiring is routed to the area and connected to the sensor; and

[0017] A support component is disposed in the area and supports the wiring.

[0018] The robotic arm involved in the application examples of this invention is characterized by having:

[0019] First component; and

[0020] The second component translates along the axis located on the first component or rotates about the axis;

[0021] The first component has:

[0022] bottom;

[0023] The drive unit generates driving force;

[0024] The joint has a driven pulley and transmits the driving force to the second component;

[0025] The belt transmits the driving force generated by the drive unit to the driven pulley;

[0026] The wiring is guided to the area surrounded by the driven pulley and the belt; and

[0027] A support component is disposed in the area and supports the wiring.

[0028] The robot system involved in the application examples of this invention is characterized by having:

[0029] Application examples of the present invention relate to robotic arms; and

[0030] A control device controls the movement of the robotic arm. Attached Figure Description

[0031] Figure 1 A side view of the robot system involved in the embodiment is shown.

[0032] Figure 2 for Figure 1 A partial sectional view of the second arm is shown.

[0033] Figure 3 To observe from the positive side of the z-axis towards the negative side Figure 1 A perspective view showing the internal structure of the second arm.

[0034] Figure 4 To view from the negative side of the z-axis towards the positive side, cut off using the xy plane. Figure 3 A partial cross-sectional perspective view of the section obtained from the second arm is shown.

[0035] Figure 5 This diagram illustrates the area surrounded by a driven pulley connected to the shaft and a belt.

[0036] Figure 6 for Figure 2 A magnified view of a portion of the diagram, showing the routing path of the wiring within the interior space.

[0037] Figure 7 for Figure 6 A magnified perspective view of the area near the support component is shown.

[0038] Figure 8 To show a partially enlarged perspective view of the robotic arm involved in the first modified example.

[0039] Figure 9 A partially enlarged perspective view is provided to show the support components of the robotic arm involved in the second variation.

[0040] Figure 10 A partially enlarged cross-sectional view of the robotic arm involved in the third variation is shown.

[0041] Explanation of reference numerals in the attached figures

[0042] 1…robot system; 2…robot; 3…control device; 4…inertial sensor; 20…robotic arm; 20A…robotic arm; 20C…robotic arm; 21…base; 22…first arm; 23…second arm; 24…axis; 29…end effector; 200…area; 201…area; 208…hollow section; 209…wiring; 210…support component; 210A…support component; 210B…support component; 211…upper end; 212…lower end; 215…width reduction section; 216…screw hole; 220…bundle strap; 225…clamp; 230…wiring; 231…bottom; 232…upper side 233… Lower cover; 235… Internal space; 236… Top plate; 237… Bottom plate; 238… Through hole; 239… Through hole; 240… Joint; 241… Ball screw nut; 242… Spline nut; 244… Payload; 261… Drive unit; 262… Drive unit; 263… Drive unit; 264… Drive unit; 274… Belt; 275… Drive pulley; 276… Driven pulley; 284… Belt; 285… Drive pulley; 286… Driven pulley; 294… Belt; 296… Driven pulley; AX1… First axis; AX2… Second axis; AX3… Third axis; L… Straight line. Detailed Implementation

[0043] The following detailed description of suitable embodiments of the robotic arm and robot system of the present invention is based on the accompanying drawings.

[0044] 1. Robot System

[0045] First, the robot system involved in the implementation method will be described.

[0046] Figure 1 A side view of the robot system 1 according to the embodiment is shown. It should be noted that, for ease of explanation, the x-axis, y-axis, and z-axis in the figures of this application are set as three mutually orthogonal axes and are indicated by arrows. In the following description, the direction parallel to the x-axis is called the "x-axis direction," the direction parallel to the y-axis is called the "y-axis direction," and the direction parallel to the z-axis is called the "z-axis direction." Furthermore, in the following description, the tip of each arrow in the illustration is called "+ (positive)," and the base is called "- (negative)." Also, for ease of explanation, the +z-axis direction is called "up," and the -z-axis direction is called "down."

[0047] Figure 1 The robot system 1 shown includes a robot 2 and a control device 3 for controlling the movement of the robot 2. The application of the robot system 1 is not particularly limited, and examples include various operations such as workpiece holding, conveying, assembling, and inspecting.

[0048] 1.1. Robot

[0049] In this embodiment, robot 2 is a horizontal articulated robot (SCARA robot). Robot 2 includes a base 21 and a robotic arm 20. In this embodiment, the robotic arm 20 includes a first arm 22, a second arm 23, an axis 24, a payload 244, and an end effector 29, which will be described later.

[0050] 1.1.1. Base

[0051] The base 21 is fixed to a surface (not shown) by bolts or the like. Examples of such surfaces include the floor, wall, ceiling, upper surface of a workbench or support. Figure 1 The base 21 shown is generally rectangular in shape. It should be noted that the shape of the base 21 is not limited to... Figure 1 The shape shown can be any shape.

[0052] The base 21 has a drive unit 261. The drive unit 261 generates a driving force that causes the first arm 22 to rotate relative to the base 21 about a first axis AX1. In addition, the drive unit 261 has an encoder (not shown) that detects the amount of rotation. The rotation angle of the first arm 22 relative to the base 21 can be detected by the output from the encoder.

[0053] 1.1.2. Robotic Arm

[0054] The robotic arm 20 is connected to the base 21, and its posture is controlled by the control device 3. This holds the end effector 29 in the intended position and posture to perform a variety of tasks. Figure 1 In the shown robotic arm 20, the first arm 22, the second arm 23 (first component), the shaft 24 (second component), the payload 244, and the end effector 29 are connected in this order. It should be noted that, for ease of explanation in the following description, the end effector 29 side of the robot 2 will be referred to as the "front end," and the base 21 side will be referred to as the "base end."

[0055] The first arm 22 is rotatable relative to the base 21 about a first axis AX1 parallel to the z-axis. The second arm 23 is disposed at the front end of the first arm 22 and is rotatable about a second axis AX2 parallel to the first axis AX1. The shaft 24 is disposed at the front end of the second arm 23 and is rotatable about a third axis AX3 parallel to the second axis AX2, and is also translatable along the third axis AX3.

[0056] The second arm 23 (first component) has a bottom 231 (main body), an upper cover 232, a lower cover 233, drive units 262, 263, 264, a joint 240, and an inertial sensor 4.

[0057] The bottom 231 is the frame of the second arm 23 and supports the drive units 262, 263, 264, etc. The upper cover 232 is located above the bottom 231 and covers the drive units 262, 263, 264, etc. The lower cover 233 is located below the bottom 231 and covers the inertial sensor 4, etc., which are mounted on the lower surface of the bottom 231.

[0058] The drive unit 262 is located at the base end of the bottom 231 and generates a driving force that causes the second arm 23 to rotate relative to the first arm 22 about the second axis AX2. The drive unit 262 includes a motor, a reducer, an encoder, etc., which are not shown. The rotation angle of the second arm 23 relative to the first arm 22 can be detected by the output from the encoder.

[0059] The drive unit 263 is located between the base end and the front end of the bottom 231, and rotates the ball screw nut 241 to generate a driving force that translates the shaft 24 in the direction along the third axis AX3. The drive unit 263 includes a motor, a reducer, an encoder, etc., which are not shown. The amount of translation of the shaft 24 relative to the second arm 23 can be detected by the output from the encoder.

[0060] The drive unit 264 is located between the base end and the front end of the bottom 231, and rotates the spline nut 242 to generate a driving force that rotates the shaft 24 about the third axis AX3. The drive unit 264 includes a motor, a reducer, an encoder, etc., which are not shown. The amount of rotation of the shaft 24 relative to the second arm 23 can be detected by the output from the encoder.

[0061] The joint 240 transmits driving force to the shaft 24. Specifically, the driving force from the drive units 263 and 264 is converted into translational and rotational movements of the shaft 24.

[0062] Shaft 24 is a cylindrical shaft. Shaft 24 is capable of translating relative to the second arm 23 along a third axis AX3 and is capable of rotating about the third axis AX3, which is vertical.

[0063] In addition, a ball screw nut 241 and a spline nut 242 are arranged in the middle of the long side of the shaft 24, and the shaft 24 is supported by these.

[0064] A payload 244 for mounting an end effector 29 is provided at the front end of shaft 24. The end effector 29 mounted on the payload 244 is not particularly limited; examples include a hand holding an object, a tool for processing an object, or an inspection device for inspecting an object. It should be noted that a robotic arm 20 can also be configured without the end effector 29.

[0065] Next, the various parts of the second arm 23 will be described in detail.

[0066] Figure 2 for Figure 1 A partial cross-sectional view of the second arm 23 is shown. Figure 3 To observe from the positive side of the z-axis towards the negative side Figure 1 A perspective view of the internal structure of the second arm 23. Figure 4 To view from the negative side of the z-axis towards the positive side, cut off using the xy plane. Figure 3 A partial sectional perspective view of the cross-section obtained from the second arm 23 is shown. Figure 5 This diagram illustrates the region 200 surrounded by driven pulleys 276 and 296 connected to shaft 24 and belts 274 and 294. It should be noted that... Figure 3 and Figure 4 The upper side cover 232 is omitted. Additionally, in... Figures 2 to 4 In this document, at least a portion of the components not described below are omitted.

[0067] The second arm 23 has Figure 5 The diagram shows belts 274, 284, 294, drive pulleys 275, 285, and driven pulleys 276, 286, 296. The aforementioned joint 240 has a driven pulley 276 connected to a ball screw nut 241 and a driven pulley 296 connected to a spline nut 242.

[0068] Figure 5 The drive pulley 275 shown is connected to Figure 3 The drive unit 263 is shown. Figure 5 The driven pulley 276 shown is connected to Figure 2 The ball screw nut 241 is shown. Figure 5 The belt 274 shown is an annular belt mounted on the drive pulley 275 and the driven pulley 276. The driving force generated by the drive unit 263 is transmitted to the ball screw nut 241 via the drive pulley 275, the belt 274, and the driven pulley 276. This allows... Figure 2 The axis 24 shown is translated in the direction along the third axis AX3, that is, in the z-axis direction.

[0069] Figure 5 The drive pulley 285 shown is connected to Figure 3 The drive unit 264 is shown. Figure 5 The driven pulley 286 shown is a deceleration pulley that transmits driving force from belt 284 to belt 294 while reducing the rotational speed. Figure 5 The driven pulley 296 shown is connected to Figure 2 The spline nut 242 is shown. Figure 5The belt 284 shown is an annular belt mounted on the drive pulley 285 and the driven pulley 286. The belt 294 is an annular belt mounted on the driven pulley 286 and the driven pulley 296. The driving force generated by the drive unit 264 is transmitted to the spline nut 242 via the drive pulley 285, belt 284, driven pulley 286, belt 294, and driven pulley 296. This allows... Figure 2 The axis 24 shown rotates about the third axis AX3.

[0070] The bottom 231 is, for example, a rigid body made of various metal materials, various hard resin materials, etc. Figure 2 The bottom 231 shown is a hollow structure and has an internal space 235, a top plate 236 (first base) disposed above the internal space 235, and a bottom plate 237 (second base) disposed below the internal space 235.

[0071] The top plate 236 has a through hole 238 (first through hole) extending in a direction parallel to the third axis AX3. The through hole 238 connects the top plate 236 above, i.e. inside the upper cover 232 and the internal space 235.

[0072] The base plate 237 has a through hole 239 (second through hole) extending in a direction parallel to the third axis AX3. The through hole 239 connects the lower part of the base plate 237, i.e., the lower side cover 233, and the internal space 235.

[0073] Through holes 238 and 239 can also function as vents to eliminate pressure differences between the upper cover 232, the internal space 235, and the lower cover 233.

[0074] It should be noted that the configuration of the bottom 231, the upper side cover 232, and the lower side cover 233 is not limited to the configuration described above. For example, at least two of them can be integrated as one unit.

[0075] Drive units 262, 263, and 264 are fixed to the upper surface of the top plate 236. Furthermore, the output shafts (not shown) of drive units 262, 263, and 264 extend within the internal space 235.

[0076] like Figure 2 and Figure 5 As shown, the internal space 235 houses pulleys 274, 284, 294, drive pulleys 275, 285, and driven pulleys 276, 286, 296.

[0077] In this embodiment, such as Figure 5As shown, the drive unit 262 is disposed at the position on the bottom 231 that overlaps with the second axis AX2. Furthermore, in this embodiment, drive units 263 and 264 are respectively disposed between the second axis AX2 and the third axis AX3 on the bottom 231. Additionally, as... Figure 5 As shown, drive units 263 and 264 are arranged along the x-axis in a manner separated by a straight line L connecting the second axis AX2 and the third axis AX3. Arranging drive units 263 and 264 along the x-axis in a manner separated by a straight line L allows for a more even distribution of weight on the second arm 23. This helps to suppress abnormal vibrations and other issues that occur during the rotation of the second arm 23. Furthermore, a driven pulley 286 is positioned between drive unit 264 and driven pulley 296. It should be noted that the arrangement of drive units 262, 263, and 264 within the bottom 231 is not limited to the configuration described above.

[0078] The inertial sensor 4 can be an angular velocity sensor that detects angular velocity, an accelerometer that detects acceleration, or a combination of both. Furthermore, there is no particular limitation on the number of axes from which the angular velocity sensor detects angular velocity; it can be one axis, two axes, or three axes. Similarly, there is no particular limitation on the number of axes from which the accelerometer sensor detects acceleration; it can be one axis, two axes, or three axes.

[0079] like Figure 2 As shown, the inertial sensor 4 is disposed on the lower surface of the base plate 237. Furthermore, the inertial sensor 4 is disposed near the third axis AX3 on the lower surface of the base plate 237. Therefore, when the second arm 23 rotates, the sensitivity of the inertial sensor 4 in detecting angular velocity and acceleration can be improved. Specifically, as... Figure 5 As shown, the inertial sensor 4 is positioned at a location that overlaps with “region 200” determined by the driven pulleys 276, 296 and belts 274, 294.

[0080] Belts 274 and 294 are wound around driven pulleys 276 and 296, respectively, which are connected to shaft 24. Therefore, as... Figure 5 As shown, when viewed from above along the third axis AX3, a region appears surrounded by belts 274 and 294 extending in the -y-axis direction from the driven pulleys 276 and 296. This region is referred to as "region 200". When viewed from above along the third axis AX3, the inertial sensor 4 is positioned on the lower surface of the base plate 237 at a location overlapping with region 200. This configuration improves the detection sensitivity of the inertial sensor 4. It should be noted that the location overlapping region 200 refers to a position where at least a portion of the inertial sensor 4 overlaps with region 200 when viewed from above. Figure 5 In the middle, a point was marked for region 200.

[0081] Wiring 209 is connected to the inertial sensor 4. Examples of wiring 209 include power lines supplying power to drive the inertial sensor 4, control signals transmitting control signals to control the operation of the inertial sensor 4, and signal lines outputting detection signals of angular velocity and acceleration detected by the inertial sensor 4. It should be noted that, even if it is an electrical wiring, it can also be an optical wiring such as an optical fiber or waveguide. Therefore, in this specification, "connected with wiring 209" refers to a state of electrical or optical connection. Wiring 209 is routed from the inside of the base 21 to the inertial sensor 4. Specifically, although not shown, wiring 209 passes through the inside of the base 21 and the first arm 22 in that order, and is routed into the inside of the upper cover 232 of the second arm 23, which is located above the top plate 236. In addition, the wiring 209 passes through the through hole 238 of the top plate 236, the through hole 239 of the region 200 and the bottom plate 237 in that order, and is guided to the inertial sensor 4.

[0082] like Figure 5 As shown, the wiring 209 is routed in such a way that it passes through region 200 in the internal space 235, thereby targeting the area provided in Figure 2 The inertial sensor 4 on the lower surface of the base plate 237 shown can guide the wiring 209 with a shorter path length. As a result, the wiring 209 can be made lighter, and the effects of signal interference transmitted through the wiring 209 can be suppressed less.

[0083] In contrast, conventional methods of fixing wiring to the inner wall of a robotic arm have presented a technical challenge: the wiring path length tends to increase. Since a longer wiring path increases the weight of the robotic arm, it is essential to lay out the wiring with the shortest possible path from a lightweight perspective. This is particularly true since functional components, often mounted at the lower part of the robotic arm, exhibit exceptionally high performance. Furthermore, timing belts and similar components are located inside the robotic arm. Therefore, there is a significant technical challenge in ensuring a suitable wiring path to the lower part of the robotic arm while minimizing the wiring path length.

[0084] However, if the wiring 209 is routed to region 200, there is a possibility that the wiring 209 may come into contact with the tapes 274 and 294, and the wiring 209 may be damaged. In particular, since the wiring 209 becomes more prone to vibration due to centrifugal force when the second arm 23 rotates, the probability of the wiring 209 coming into contact with the tapes 274 and 294 increases.

[0085] Therefore, in this embodiment, as Figure 5 As shown, a support member 210 is provided in region 200. For example... Figure 4As shown, the support member 210 passes through the inner side of the belts 274 and 294 from the top plate 236, and as... Figure 2 As shown, it is columnar, extending to the base plate 237. Furthermore, the wiring 209 is supported by this support member 210. Therefore, while guiding the wiring 209 along the support member 210, it is possible to suppress the swaying of the wiring 209. As a result, the wiring 209 can be appropriately wound with a short path length, and the probability of the wiring 209 contacting the tapes 274 and 294 can be reduced. Additionally, as... Figure 2 As shown, when viewed from above along the X-axis, the support member 210 extends from the through hole 238 toward the -Z-axis and bends toward the through hole 239 at the position where it overlaps with the belt 294.

[0086] Figure 6 yes Figure 2 This is a partial enlarged view, and it is a diagram showing the winding path of wiring 209 in the internal space 235.

[0087] The wiring 209 is wound around the support member 210 and supported by the support member 210. "Support" means fixing the wiring 209 to the support member 210 to a degree that prevents the wiring 209 from swaying. The fixing method is not particularly limited; methods such as using adhesive or wrapping the wiring 209 around the support member 210 can be used. However, in this embodiment, a binding strap 220 (tethering member) is used. Using the binding strap 220 allows for easy and quick fixing of the wiring 209 to the support member 210. It should be noted that, in addition to the binding strap 220, other tethering members can include clips, ropes, rubber bands, adhesive tape, etc.

[0088] Figure 7 for Figure 6 A partially enlarged perspective view of the vicinity of the support member 210 is shown. It should be noted that... Figure 7 The illustrations of clamp 225, wiring 209, and bundling strap 220 are omitted. Additionally, in... Figure 7 The diagram shows a cross-section of a portion of the area.

[0089] Figure 7 The support member 210 shown is cylindrical with a generally constant width, but has a width-reducing portion 215 where the width locally narrows. The width of the support member 210 refers to the length of the cylindrical support member 210 in the direction of its short side, which is orthogonal to the direction of its long side. When the strapping 220 is installed onto the support member 210, the width-reducing portion 215 helps to suppress the positional deviation of the strapping 220. That is, after the strapping 220 is installed onto the width-reducing portion 215, the strapping 220 becomes less likely to deviate from the width-reducing portion 215. Therefore, it is possible to suppress malfunctions that accompany unexpected positional deviations of the strapping 220.

[0090] in addition, Figure 7 The support member 210 shown has its upper end 211 (one end) fixed to the upper side of the top plate 236, passing through the through hole 238, the inner side of the straps 274 and 294, and the through hole 239, while its lower end 212 (the other end) is fixed to the lower side of the bottom plate 237. By fixing both ends to the bottom 231 in this way, the swaying of the support member 210 itself can be suppressed, and as a result, the swaying of the wiring 209 can be suppressed. Methods for fixing the support member 210 to the bottom 231 include, for example, screw fastening, fitting, adhesive fastening, and fastening with clips. Furthermore, in the support member 210, such as... Figure 7 As shown, the upper end 211 is plate-shaped along the top plate 236, and a portion of the plate is curved toward the through hole 238.

[0091] Alternatively, the support member 210 can also be integrated with the bottom 231, but Figure 7 The support member 210 shown is a separate entity from the bottom 231. Therefore, an assembly sequence can be adopted in which the support member 210 is installed onto the bottom 231 after the belts 274 and 294 are installed. As a result, the support member 210 can be prevented from becoming an obstacle when installing the belts 274 and 294.

[0092] In addition, as a component of the support member 210, in addition to metal materials such as ferrous alloys like stainless steel, aluminum alloys, and titanium alloys, resin materials and ceramic materials can also be mentioned.

[0093] It should be noted that the support component 210 only needs to pass through region 200, and is preferably configured to avoid the area where belts 274 and 294 vibrate. The area where belts 274 and 294 vibrate refers to the amplitude of the deflection of belts 274 and 294 when the second arm 23 rotates. By setting region 200 to avoid such a range, the wiring 209 becomes less susceptible to damage even when belts 274 and 294 vibrate.

[0094] like Figure 6 As shown, above the top plate 236, in addition to the wiring 209, there is also wiring 230 connecting various devices within the robotic arm 20 to the base 21. Regarding these wirings 209 and 230, to suppress their swaying during rotation of the second arm 23, it is preferable to bundle them. In this embodiment, as... Figure 6 As shown, the wires 209 and 230 are bundled by clamps 225 fixed to the support member 210. This suppresses the swaying of the wires 209 and 230 and makes it easier to guide the wire 209 to the vicinity of the support member 210. Consequently, the wire 209 can be wound to the support member 210 via a shorter path.

[0095] It should be noted that the method by which the clamp 225 is fixed to the support component 210 is not particularly limited; for example, it can be fixed by screw tightening, by fitting, or by adhesive. Figure 7 The middle figure shows a screw hole 216 provided at the upper end 211 of the support member 210 for fixing the clamp 225. It should be noted that the clamp 225 may also be fixed to the bottom 231 instead of the support member 210.

[0096] As described above, the robotic arm 20 according to the embodiment includes a second arm 23 (first component) and a shaft 24 (second component). The shaft 24 translates along or rotates about a third axis AX3 located on the second arm 23.

[0097] Additionally, the second arm 23 has a base 231, drive units 263 and 264 that generate driving force, a joint 240, belts 274 and 294, an inertial sensor 4 serving as a vibration detection sensor, wiring 209, and a support member 210 supporting the wiring 209. The joint 240 has driven pulleys 276 and 296 and transmits driving force to the shaft 24. The belts 274 and 294 transmit the driving force generated by the drive units 263 and 264 to the driven pulleys 276 and 296. When viewed from above along the third axis AX3, the inertial sensor 4 is positioned at a location overlapping the region 200 surrounded by the driven pulleys 276 and 296 and the belts 274 and 294. The wiring 209 is wound around the region 200 and connected to the inertial sensor 4. The support member 210 is located in the region 200 and supports the wiring 209.

[0098] With this configuration, even when the wiring 209 is subjected to centrifugal force, the swaying of the wiring 209 can be suppressed. As a result, the probability of the wiring 209 coming into contact with the tapes 274 and 294 can be reduced, and damage to the wiring 209 can be suppressed.

[0099] Furthermore, even when the inertial sensor 4 is positioned at the lower part of the second arm 23, overlapping with region 200, the path length of the wiring 209 can be shortened by placing the support member 210 in region 200. This allows for weight reduction of the wiring 209, and further suppresses the effects of signal interference transmitted through the wiring 209.

[0100] It should be noted that in this embodiment, the shaft 24 may be able to translate along the third axis AX3 and rotate about the third axis AX3, which is vertical. However, these actions involving the shaft 24 may be either one or the other. Furthermore, in this embodiment, the joint 240 has both a ball screw nut 241 and a spline nut 242, or either one may be omitted. It should be noted that when the ball screw nut 241 is omitted, the aforementioned region 200 simply becomes the region surrounded by the belt 294 and the driven pulley 296. On the other hand, when the spline nut 242 is omitted, the aforementioned region 200 simply becomes the region surrounded by the belt 274 and the driven pulley 276.

[0101] On the other hand, region 200 in this embodiment is obtained by merging the region surrounded by belt 294 and driven pulley 296 and the region surrounded by belt 274 and driven pulley 276. Thus, as... Figure 5 As shown, region 201 exists within region 200, comprising either a region surrounded by belt 294 and driven pulley 296 or a region surrounded by belt 274 and driven pulley 276. The inertial sensor 4 can be positioned at a location overlapping region 200, but it is preferable to position it at a location overlapping region 201. This, in particular, improves the detection sensitivity of the inertial sensor 4. Figure 5 In the middle, area 201 is marked with a diagonal line.

[0102] It should be noted that, in Figure 5 In this configuration, when the straight line L connecting the second axis AX2 and the third axis AX3 is drawn, region 201 overlaps with straight line L, and inertial sensor 4 also overlaps with straight line L. This configuration is particularly preferred from the viewpoint of the detection sensitivity of inertial sensor 4.

[0103] Furthermore, the shape of the support member 210 can be any shape as long as it can support the wiring 209, but in this embodiment, it is a columnar shape that passes through the inside of the strips 274 and 294 and extends therein. Additionally, the wiring 209 is supported along the support member 210.

[0104] With this configuration, the wiring 209 can be guided along the support member 210 and its swaying can be suppressed. As a result, the wiring 209 can be properly wound and the probability of the wiring 209 contacting the tapes 274 and 294 can be reduced.

[0105] Furthermore, in the robotic arm 20 according to this embodiment, the bottom 231 has a top plate 236 (first base) and a bottom plate 237 (second base) that are opposite to each other separated by an internal space 235. The internal space 235 is a space through which belts 274 and 294 pass. In addition, the upper end 211 (one end) of the support member 210 is fixed to the top plate 236, while the lower end 212 (the other end) is fixed to the bottom plate 237.

[0106] With this configuration, the swaying of the support member 210 itself can be suppressed. Furthermore, since the support member 210 is a separate entity from the bottom 231, an assembly sequence can be adopted in which the support member 210 is installed onto the bottom 231 after the straps 274 and 294 are installed. As a result, the support member 210 can be prevented from becoming an obstacle when installing the straps 274 and 294.

[0107] Furthermore, in the robotic arm 20 according to this embodiment, the top plate 236 (first base) has a through hole 238 (first through hole) extending in a direction parallel to the third axis AX3, and the bottom plate 237 (second base) has a through hole 239 (second through hole) extending in a direction parallel to the third axis AX3. Additionally, the wiring 209 can be wound around the through hole 238, the internal space 235, and the through hole 239.

[0108] With this configuration, the wiring 209 can be routed with a shorter path length without detours in the top plate 236 and bottom plate 237. As a result, the wiring 209 can be made lighter, and the effects of signal interference transmitted through the wiring 209 can be further suppressed.

[0109] Additionally, the robotic arm 20 of this embodiment has a strap 220 (tethering member) for securing the wiring 209 to the support member 210.

[0110] The use of the cable ties 220 makes it easy to secure the wiring 209 to the support member 210.

[0111] Furthermore, in the robotic arm 20 of this embodiment, the support member 210 has a width-reducing portion 215 with a locally narrowed width. The binding strap 220 (tethering member) binds the wiring 209 to the width-reducing portion 215.

[0112] With this configuration, the strapping 220 becomes difficult to move from the width-reduced portion 215 to its outer side. As a result, malfunctions that accompany unexpected positional deviations of the strapping 220 can be suppressed.

[0113] It should be noted that Robot 2 is not limited to the SCARA robot mentioned above, but can also be other robots such as vertical joint robots or Cartesian coordinate robots. In addition, there is no particular limitation on the number of arms that a vertical joint robot has.

[0114] 1.2. Control Device

[0115] The movements of robot 2 are controlled by control device 3. For example... Figure 1 As shown, the control device 3 can be disposed outside the base 21, or it can be built into the base 21. The control device 3 controls the drive units 261, 262, 263, and 264 according to a pre-stored motion program. Thus, the control device 3 controls the movement of the robotic arm 20.

[0116] As described above, the robot system 1 of this embodiment includes a robotic arm 20 and a control device 3 for controlling the movement of the robotic arm 20.

[0117] According to this robot system 1, even when the robotic arm 20 is moving, the swaying of the wiring 209 connected to the inertial sensor 4 can be suppressed. Therefore, damage to the wiring 209 can be suppressed. Furthermore, the path length of the wiring 209 can be kept shorter. As a result, a robot system 1 can be realized that allows the robotic arm 20 to move at high speeds, and even under such conditions, damage to the wiring 209 is difficult to occur.

[0118] 2. First variation

[0119] Next, the robotic arm involved in the first variation will be described.

[0120] Figure 8 This is a partially enlarged perspective view of the robotic arm 20A involved in the first modified example. It should be noted that... Figure 8 The diagram shows cross-sections of some parts.

[0121] The first modified example will be described below. In this description, the focus will be on the differences from the described embodiment; identical details will be omitted. It should be noted that... Figure 8 The same reference numerals are used for components that are the same as those in the described embodiments.

[0122] exist Figure 8In the illustrated robotic arm 20A, similar to the embodiment described above, the bottom 231 includes a top plate 236 (first base) and a bottom plate 237 (second base) that are opposite to each other and separated by an internal space 235. The internal space 235 is the space through which belts 274 and 294 pass. Furthermore, the upper end 211 (one end) of the support member 210A is fixed to the top plate 236, while the lower end 212 (the other end) is located away from the bottom plate 237.

[0123] With this configuration, since the gap exists between the lower end 212 of the support member 210A and the base plate 237, the belts 274 and 294 can be passed through and installed using this gap. Therefore, an assembly sequence in which the belts 274 and 294 are installed after the support member 210A is pre-fixed to the bottom 231 can be adopted. On the other hand, since the support member 210A is also a separate entity from the bottom 231, even in this first modification, as in the aforementioned embodiment, an assembly sequence in which the support member 210A is installed on the bottom 231 after the belts 274 and 294 are installed can also be adopted.

[0124] It should be noted that as long as the upper end 211 of the support component 210A is fixed, it can support the wiring 209 while suppressing the swaying of the wiring 209.

[0125] In addition, in this first modified example, the upper end 211 of the support member 210A is fixed to the bottom 231, while the lower end 212 is away from the bottom 231. Conversely, the lower end 212 may be fixed to the bottom 231, while the upper end 211 is away from the bottom 231.

[0126] 3. Second variation

[0127] Next, the robotic arm involved in the second variation will be described.

[0128] Figure 9 This is a partially enlarged perspective view showing the support component 210B of the robotic arm involved in the second modified example.

[0129] The second variation will be described below. In this description, the focus will be on the differences from the described embodiment; identical details will be omitted. It should be noted that... Figure 9 The same reference numerals are used for components that are the same as those in the described embodiments.

[0130] Figure 9 The support member 210B shown has a hollow portion 208 in its cross-sectional shape. The cross-sectional shape refers to the cross-sectional shape obtained by cutting the support member 210B with a plane orthogonal to its long side. Specifically, the cross-sectional shape of the support member 210B is as follows: Figure 9 As shown, it is an annular shape surrounding the circular hollow portion 208. In addition, at least a portion of the wiring 209 can be wound around the hollow portion 208 in a manner that converges to the hollow portion 208.

[0131] With this configuration, at least a portion of the wiring 209 is contained within the hollow portion 208 and not exposed to the outside. Therefore, it is particularly effective in reducing the contact area between the wiring 209 and the outside. Figure 8 The probabilities of bands 274, 294, and other objects are shown. As a result, wiring 209 becomes particularly difficult to damage.

[0132] It should be noted that, in addition to the aforementioned annular shape, other shapes with a partially discontinuous annular shape (C-shaped), a polygonal annular shape, or a partially discontinuous annular shape can also be used for the hollow portion 208. In the case of a C-shaped or partially discontinuous annular shape, the wiring 209 can be inserted into the hollow portion 208 from the discontinuous portion. Therefore, the support member 210B with such a cross-section is useful in facilitating the winding operation of the wiring 209.

[0133] 4. Third variation

[0134] Next, the robotic arm involved in the third variation will be explained.

[0135] Figure 10 A partially enlarged cross-sectional view of the robotic arm 20C involved in the third variation is shown.

[0136] The third variation will be described below. In this description, the focus will be on the differences from the described embodiment; identical details will be omitted. It should be noted that... Figure 10 The same reference numerals are used for components that are the same as those in the described embodiments.

[0137] exist Figure 10 In the illustrated robotic arm 20C, similar to the embodiment described above, the wiring 209 is supported by the support member 210. Furthermore, in the robotic arm 20C, the wiring 209 is electrically connected to the end effector 29.

[0138] The end effector 29 is mounted on the front end of the shaft 24. Therefore, similar to the embodiment described above, by supporting the wiring 209 with the support member 210, the path length of the wiring 209 can be reduced while suppressing the effects of signal interference transmitted through the wiring 209. Furthermore, by supporting the wiring 209 with the support member 210, swaying of the wiring 209 and damage to the wiring 209 can be suppressed.

[0139] It should be noted that the wiring 209 can also be a wiring formed by bundling multiple strands of wire. In this case, the wiring 209 can be connected to both the inertial sensor 4 and the end effector 29. Furthermore, the wiring 209 can also be connected to functional units other than the end effector 29. Examples of functional units include, in addition to image sensors such as cameras, various sensors such as depth sensors, range sensors, and force sensors, projectors that project images.

[0140] As described above, the robotic arm 20C in the third variation includes a second arm 23 (first component) and a shaft 24 (second component). The shaft 24 translates along or rotates about a third axis AX3 located at the front end of the second arm 23.

[0141] Additionally, the second arm 23 has a bottom 231 that generates driving force. Figure 5 The diagram shows drive units 263 and 264, joint 240, belts 274 and 294, wiring 209, and support member 210 supporting wiring 209. Joint 240 has driven pulleys 276 and 296 and transmits driving force to shaft 24. Belts 274 and 294 transmit the driving force generated by drive units 263 and 264 to driven pulleys 276 and 296. Wiring 209 is wound around the region 200 surrounded by driven pulleys 276 and 296 and belts 274 and 294. Support member 210 is provided in region 200 and supports wiring 209.

[0142] With this configuration, even when the wiring 209 is subjected to centrifugal force, the swaying of the wiring 209 can be suppressed. As a result, the probability of the wiring 209 coming into contact with the tapes 274 and 294 can be reduced, and damage to the wiring 209 can be suppressed.

[0143] Furthermore, when a functional component, such as the end effector 29, is mounted on the front end of the shaft 24, the wiring 209 can be easily connected to the functional component. Additionally, even in this third modification, because the support member 210 is disposed in region 200, the path length of the wiring 209 can be kept relatively short. This results in a lighter wiring 209 and further reduces the impact of signal interference transmitted through the wiring 209.

[0144] The robotic arm and robot system of the present invention have been described above based on the illustrated embodiments. However, the robotic arm and robot system of the present invention are not limited to the embodiments described. For example, it may be a robotic arm and robot system obtained by replacing each part of the embodiments with each part of any configuration having the same function, or it may be a robotic arm and robot system obtained by adding any structure to the embodiments, or it may be a robotic arm and robot system obtained by combining multiple embodiments.

Claims

1. A robot arm, characterized in that, Possessing: a first arm that rotates around a first axis; a second arm that rotates around a second axis that is parallel to the first axis of the first arm; and a shaft that translates along a third axis or rotates around the third axis that is parallel to the second axis of the second arm, the second arm has: a base; a first drive section that generates a first driving force; a second drive section that generates a second driving force; a first drive pulley connected to the first drive section; a second drive pulley connected to the second drive section; a first driven pulley and a second driven pulley provided to the shaft; an intermediate pulley that is disposed between the second drive section and the second driven pulley when viewed in the direction of the third axis, and that transmits the driving force while reducing the rotational speed; a first belt that is stretched between the first drive pulley and the first driven pulley; an intermediate belt that is stretched between the second drive pulley and the intermediate pulley; a second belt that is stretched between the intermediate belt and the second driven pulley; a sensor that is provided at a position lower than the first belt and the second belt in the vertical direction, and that detects at least one of an angular velocity and an acceleration; a support member that passes through an inner side of a belt region obtained by combining a first region surrounded by the first driven pulley and the first belt and a second region surrounded by the second driven pulley and the second belt when viewed in the direction of the third axis; and a wire that is connected to the sensor, passes through the inner side of the belt region when viewed in the direction of the third axis, and is supported by the support member.

2. The robot arm according to claim 1, wherein the support member is columnar that passes through the inner side of the belt region and extends, the wire is supported along the support member.

3. The robot arm according to claim 2, wherein the base has a first base body and a second base body that face each other with an internal space through which the first belt or the second belt passes, one end of the support member is fixed to the first base body, and the other end is fixed to the second base body.

4. The robot arm according to claim 2, wherein the base has a first base body and a second base body that face each other with an internal space through which the first belt or the second belt passes, one end of the support member is fixed to the first base body, and the other end is away from the second base body.

5. The robot arm according to claim 3 or 4, wherein the first base body has a first through-hole that penetrates in a direction parallel to the third axis, the second base body has a second through-hole that penetrates in a direction parallel to the third axis, the wire is routed through a path that passes through the first through-hole, the internal space, and the second through-hole.

6. The robot arm according to any one of claims 2 to 4, wherein the support member is shaped like a hollow section in a cross-sectional shape, at least a portion of the wire is bundled in the hollow section. ​ 7. The robot arm according to any one of claims 2 to 4, characterized in that, the robot arm has a tethering member that tethers the wiring bundle to the support member.

8. The robot arm according to claim 7, characterized in that, the support member has a width-reducing portion in which the width is locally narrowed, the tethering member tethers the wiring bundle to the width-reducing portion.

9. A robot arm, characterized in that provided with: a first arm that rotates around a first axis; a second arm that rotates around a second axis that is parallel to the first axis of the first arm; and a shaft that translates along a third axis or rotates around the third axis that is parallel to the second axis of the second arm, the second arm has: a base portion; a first drive portion that generates a first drive force; a second drive portion that generates a second drive force; a first drive pulley that is connected to the first drive portion; a second drive pulley that is connected to the second drive portion; a first driven pulley and a second driven pulley that are provided to the shaft; an intermediate pulley that is disposed between the second drive portion and the second driven pulley when viewed along the third axis, and that transmits the drive force while reducing the rotational speed; a first belt that is stretched between the first drive pulley and the first driven pulley; an intermediate belt that is stretched between the second drive pulley and the intermediate pulley; a second belt that is stretched between the intermediate belt and the second driven pulley; a support member that passes inside an overlapping region included in either of a first region and a second region when viewed along the third axis, the first region being a region surrounded by the first driven pulley and the first belt, and the second region being a region surrounded by the second driven pulley and the second belt; and wiring that passes inside the overlapping region when viewed along the third axis, and that is supported by the support member.

10. A robot system, characterized by provided with: the robot arm according to any one of claims 1 to 9; and a control device that controls the operation of the robot arm.

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