JP7787393B2 - Sensor unit and industrial robot - Google Patents

Description

The present invention relates to a sensor unit and an industrial robot.

Some industrial robots, such as articulated robots in which multiple links are connected in a series, are configured to be able to detect when a link comes into contact with an object (obstacle), such as a person. For example, the industrial robot described in Patent Document 1 has a detection function that detects contact based on the abnormal torque generated when it comes into contact with an object, and protects the industrial robot and the object by stopping the industrial robot (protective stop) when contact is detected.

Japanese Patent Application Laid-Open No. 2005-103674

In the detection method described above, abnormal torque is determined using the same threshold value regardless of the distance from the point of contact with the object to the joint. This results in differences in contact detection accuracy and responsiveness depending on the point of contact. For example, detection accuracy and responsiveness are lower at points closer to the joint than at points farther away. Furthermore, if the threshold value is lowered to anticipate contact close to the joint, production efficiency may decrease due to an increase in unnecessary protective stops. In contrast, if the surface of the arm (link) is covered with a sensor unit having a detection section that detects contact with or approach to an object, the above-mentioned concerns about detection accuracy and responsiveness can be eliminated.

When using this type of sensor unit, it is preferable to minimize the area on the arm surface where the detection unit is not located, i.e., the non-detection area that does not detect contact, etc. On the other hand, minimizing the non-detection area places greater restrictions on the detection unit's mounting structure, and it is expected that the mounting structure on the arm (the mounting area for the detection unit) will be hidden by the detection unit and become difficult to see. In other words, it is expected that workability when installing the detection unit will be reduced. This is undesirable because it could lead to work errors such as incomplete installation of the detection unit. Furthermore, there is a concern that the above-mentioned protective function will not be properly performed if the industrial robot operates with the detection unit incompletely installed. As such, there is still room for improvement in the sensor unit's configuration in order to increase the area of the arm covered by the detection unit, i.e., the monitoring range of the sensor unit, while increasing the reliability of the sensor unit's installation.

The present invention was made in consideration of the above circumstances, and its main purpose is to increase the reliability of sensor unit installation while expanding the monitoring range of the sensor unit.

The following describes the means to solve the above problems.

First means: A sensor unit applied to an industrial robot having an arm in which a plurality of links, including a predetermined link formed so that at least a portion thereof is linear, are connected in series,
a plurality of detectors that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member attached to the predetermined link and having mounting portions to which a pair of adjacent detection units among the plurality of detection units are attached;
The attachment portion of the holder member is configured to be located at the boundary between the pair of adjacent detection portions.

According to the configuration shown in Means 1, a holder member is attached to a predetermined link, and detectors are attached to the holder member, thereby covering the predetermined link. By configuring the sensor unit as a combination of multiple detectors, it is possible to comfortably cover a wide area of the predetermined link. This is advantageous for widening the monitoring range of the sensor unit and reducing detection misses. Adjacent pairs of detectors are attached to the mounting portion of the holder member. Because this mounting portion is located at the boundary between the detectors, when installing the detectors, the positional relationship between the detectors and the mounting portion can be visually confirmed. This reduces the likelihood of operational errors, such as incomplete installation of the detectors. In other words, it is possible to increase the reliability of sensor unit installation while widening the monitoring range of the sensor unit on the arm.

FIG. 1 is a perspective view of a robot according to a first embodiment. Side view of the robot. FIG. 10 is a perspective view showing a state in which the sensor unit is removed from the robot body. FIG. FIG. 5A and 5B are schematic diagrams showing the procedure for attaching and detaching the sensor unit. FIG. 10 is a perspective view showing a state in which the sensor unit is removed from the robot body. FIG. FIG. FIG. 9 is a partial cross-sectional view taken along line AA in FIG. 8. 8A to 8C are schematic diagrams showing the procedure for attaching and detaching the second sensor unit. 5A and 5B are schematic diagrams showing the flow of unlocking. FIG. 10 is a schematic diagram showing the arrangement of cables in the second embodiment. FIG. 4 is a schematic diagram showing the relationship between a holder and a cable holder.

First Embodiment
A first embodiment will be described below with reference to the drawings. This embodiment is embodied in an industrial robot capable of working in collaboration with humans in a machine assembly factory.

As shown in Figure 1, the robot 10 has a vertically articulated robot body 11. The robot body 11 has a base 21 that is fixed to the floor or the like, and an arm 22 made up of multiple links connected in series. Although some parts are not shown in Figure 1, a group of sensor units 12 capable of detecting contact with an object such as a person is attached to the outer periphery of each link of the arm 22.

The arm 22 has, as its multiple links, a shoulder portion 23 supported by the base 21, a lower arm portion 24 supported by the shoulder portion 23, a first upper arm portion 25 supported by the lower arm portion 24, a second upper arm portion 26 supported by the first upper arm portion 25, a wrist portion 27 supported by the second upper arm portion 26, and a flange portion 28 supported by the wrist portion 27. An end effector 29 is attached to the flange portion 28. The robot 10 can be equipped with multiple types of end effectors depending on the type of work being performed.

As shown in FIG. 2, the base 21 and the shoulder portion 23 are formed with a first joint J1 that connects them, and the shoulder portion 23 is rotatable horizontally around the connecting axis AX1 of the first joint J1. The shoulder portion 23 and the lower arm portion 24 are formed with a second joint J2 that connects them, and the lower arm portion 24 is rotatable vertically around the connecting axis AX2 of the second joint J2. The lower arm portion 24 and the first upper arm portion 25 are formed with a third joint J3 that connects them, and the first upper arm portion 25 is rotatable vertically around the connecting axis AX3 of the third joint J3. The first upper arm 25 and the second upper arm 26 are formed with a fourth joint J4 that connects the first upper arm 25 and the second upper arm 26, and the second upper arm 26 is rotatable in a torsional direction around the connecting axis AX4 of the fourth joint J4. The second upper arm 26 and the wrist 27 are formed with a fifth joint J5 that connects the second upper arm 26 and the wrist 27, and the wrist 27 is rotatable in an up-down direction around the connecting axis AX5 of the fifth joint J5. The wrist 27 and the flange 28 are formed with a sixth joint J6 that connects the wrist 27 and the flange 28, and the flange 28 is rotatable in a torsional direction around the connecting axis AX6 of the sixth joint J6.

Motors M1 to M6 (specifically, servo motors) are provided at each joint J1 to J6 as drive units for rotating the joints J1 to J6, and the motors M1 to M6 are connected to a motion controller 33 via a servo amplifier 32. The motion controller 33 can be connected to a host controller C via external input/output terminals 34 provided on the base 21, and controls the drive of the motors M1 to M6 based on commands from the host controller C.

Specifically, the motion controller 33 receives a command from the host controller C, reads an operation program corresponding to the command from the program storage unit, and identifies a target operation position from the read operation program. It then generates a target trajectory that smoothly connects the identified target operation position with the current position of the arm 22, and sequentially transmits interpolated positions, which are positions obtained by subdividing the target trajectory, to the servo amplifier 32.

The servo amplifier 32 is connected to the encoders attached to the motors M1 to M6, and detects the rotational positions of the motors M1 to M6 (i.e., the posture of the arm 22) based on the encoder values. It then calculates the target torque and target rotational speed for each motor M1 to M6 based on the deviation between the detected rotational position and the interpolated position included in the command received from the motion controller 33, determines the power (current, voltage, pulses) to be supplied to each motor M1 to M6 based on the calculated target torque and target rotational speed, and supplies power to each motor M1 to M6. The servo amplifier 32, motion controller 33, and host controller C together make up the control system for the robot 10.

A connection terminal 28a is provided on the outer periphery of the flange portion 28, to which a cable 30 extending from the end effector 29 can be connected, and wiring connecting the connection terminal 28a to an external input/output terminal 34 of the base 21 is housed (built-in) in the robot main body 11. This wiring is connected to the motion controller 33 and the external input/output terminal 34, and by connecting the cable 30 extending from the end effector 29 to the connection terminal 28a, the end effector 29 can be connected to the motion controller 33 and the higher-level controller C.

The control system shown in this embodiment has a detection function that detects contact based on abnormal torque generated when the arm 22 comes into contact with an object, such as a person. When contact is detected, the robot main body 11 is stopped (protective stop) to protect the robot main body 11 and the object. However, in this detection method, the same threshold value is used to determine abnormal torque regardless of the distance from the contact point with the object to the joint. This results in differences in contact detection accuracy and responsiveness depending on the contact point. For example, detection accuracy and responsiveness are lower at positions closer to the joint than at positions further away. Furthermore, if the threshold value is lowered to anticipate contact close to the joint, unnecessary protective stop operations may increase, reducing production efficiency. In the robot 10 shown in this embodiment, the arm 22 is covered by a sensor unit group 12 equipped with a planar detector that detects contact with an object. When the sensor unit group 12 detects contact, the robot 10 is stopped (protective stop). In other words, a protective stop is performed not only when abnormal torque is determined to have occurred, but also when contact is directly detected by the sensor unit group 12.

Here, the sensor unit group 12 shown in FIG. 1 is broadly classified into two groups based on the shape of the link, etc. Specifically, they are classified into sensor unit groups applied to linear portions of the link (hereinafter referred to as linear portions) and sensor unit groups applied to curved portions of the link (hereinafter referred to as curved portions). In this embodiment, although some sensor units are not shown, the lower arm portion 24 and first upper arm portion 25 are applicable to sensor units for linear portions, and the second upper arm portion 26 and wrist portion 27 are applicable to sensor units for curved portions. Below, sensor units applied to curved portions will be described using sensor unit 50 for wrist portion 27 as an example, first with reference to FIGS. 3 and 4.

As shown in Figure 3, the wrist portion 27 is bent at its midpoint, forming an L-shape overall. In other words, the wrist portion 27 is composed of a straight portion 41a that connects to the second upper arm portion 26 and extends in the same direction as the connecting axis AX5, a straight portion 41b that connects to the flange portion 28 and extends in the same direction as the connecting axis AX6, and a bent portion 41c that connects the straight portions 41a and 41b.

The sensor unit 50 has a planar detection section 51 that covers the bent portion 41c from the outside of the bend. More specifically, the detection section 51 faces the bent outside of the bent portion 41c and the straight sections 41a and 41b, and the side of the wrist portion 27 (see Figure 4). As shown in Figure 4, an operation button 27a that is operated by the user when performing direct teaching or the like is provided on the side of the wrist portion 27. Although the detection section 51 covers the side of the wrist portion 27, a portion of the edge 55 of the detection section 51 is cut out so that the operation button 27a is outside the area covered by the detection section 51.

The detection unit 51 is composed of a base frame 52 made of hard resin (e.g., polycarbonate) that abuts the outer surface of the wrist portion 27 and a cover 53 made of soft resin (e.g., silicone) that covers the base frame 52 from the outside. A sheet-like pressure sensor (not shown) is housed between the base frame 52 and the cover 53. When an object such as a person hits the cover 53, the cover 53 deforms, and the deformed cover 53 presses the pressure sensor. This causes a signal to be output that indicates contact with the object.

A housing 43 for housing a connector 44 on the robot main body 11 is formed by recessing a portion of the bending portion 41c of the wrist 27 on the outer side of the bending. This housing 43 is covered by a removable cover 42. When attaching the sensor unit 50 to the robot main body 11, the connector 44 on the robot main body 11 is connected to the connector 54 on the sensor unit 50, and a signal indicating contact is input to the robot main body 11.

Next, the mounting structure of the sensor unit 50 will be described. Fasteners 70, 80 for mounting the detection unit 51 to the wrist 27 are arranged on each of the side portions 56, 57 of the detection unit 51 that face the wrist 27 from the side. These fasteners 70, 80 are both fixed to the base frame 52, and the fixing points are specified to be away from the edge 55 of the detection unit 51 (side portions 56, 57) (points closer to the center of the detection unit 51).

The fastener 70 is a long hook-and-loop fastener with one end fixed to the side portion 56 (base frame 52), and one surface has a hook portion 71 and a loop portion 72 that connects to the hook portion 71. The hook portion 71 and the loop portion 72 are aligned in the longitudinal direction of the fastener 70, and a blank portion 73 is provided between the hook portion 71 and the loop portion 72, where neither the hook portion 71 nor the loop portion 72 is formed.

The fastener 80 is composed of a long belt 81, one end of which is fixed to the side portion 57 (base frame 52), and a connecting plate 82, which is fixed to the other end (tip) of the belt 81. Here, we will provide additional information about the connecting plate 82 with reference to Figure 5.

The connecting plate 82 has a ring portion 84 with a horizontally elongated opening 83. The belt 81 is inserted through this opening 83 and folded back from the opening 83 to form a double layer. The double layer is then sewn together, thereby inseparably joining the belt 81 and connecting plate 82. The fastener 70 can be inserted into the opening 83 along with the belt 81. The fastener 70 inserted through the opening 83 is folded back to join the hook portion 71 and loop portion 72, thereby joining the fasteners 70 and 80 together in a continuous manner.

A recess 86 is formed by recessing the plate surface 82a of the connecting plate 82 in a portion adjacent to the ring portion 84, specifically the portion where the fastener 70 is folded back during connection. Like the ring portion 84 and opening 83, the recess 86 is also elongated horizontally, with its width slightly larger than that of the fastener 70. This allows a portion of the doubled portion of the fastener 70 to be accommodated in the recess 86 when the fastener 70 is folded back from the opening 83. By accommodating the fastener 70 in the recess 86, the side walls of the recess 86 prevent the fastener 70 from shifting laterally. The ranges in which the hook portion 71, loop portion 72, and blank portion 73 are formed are specified so that when the sensor unit 50 is attached to the wrist 27, the hook portion 71 and loop portion 72 are joined at a position away from the connecting plate 82, and the doubled portion of the blank portion 73 is located in the recess 86.

The depth of the recess 86 is slightly greater than the thickness of the doubled fastener 70, specifically the thickness of the doubled portion of the blank and the portion where the hook portion 71 and loop portion 72 are joined. A long, plate-shaped restricting member 90 is fixed to the connecting plate 82 to prevent the fastener 70 from slipping out of the recess 86. Specifically, the restricting member 90 covers the recess 86, with both ends extending to the left and right from the recess 86. These extending portions abut against the plate surface 82a of the connecting plate 82. Screw holes 87 are formed in the connecting plate 82 at the portions abutting the restricting member 90 (on the left and right of the recess 86), and the restricting member 90 is formed with communication holes 91 that communicate with the screw holes 87. Screws 95 are inserted into the communication holes 91 and then threaded into the screw holes 87, securing the restricting member 90 to the connecting plate 82. The gap between the restricting member 90 and the bottom surface 86a is smaller than the thickness of the fastener 70 when doubled, and the fastener 70 housed in the recess 86 is sandwiched between the connecting plate 82 and the restricting member 90 by tightening the screw 95. It can be said that the connecting plate 82, restricting member 90, and screw 95 form a buckle that secures the fastener 70.

Next, with reference to Figures 5 and 6, the workflow for attaching and detaching the sensor unit 50 to and from the wrist 27 will be explained in the order of attachment and detachment.

When attaching the sensor unit 50 to the wrist 27, as shown in FIG. 6(a), the cover 42 is removed from the wrist 27 to expose the connector 44. Next, as shown in FIG. 6(b), before placing the sensor unit 50 over the bent portion 41c, the connector 44 on the wrist 27 side is connected to the connector 54 on the sensor unit 50 side. Thereafter, as shown in FIG. 6(c), the sensor unit 50 is assembled to the wrist 27 by placing it over the outer side of the bent portion. As a result, the portion formerly covered by the cover 42 (the storage portion 43) is now covered by the sensor unit 50. In this state, the detection portion 51 abuts against the straight portion 41a of the wrist 27, preventing the detection portion 51 from shifting toward the flange portion 28. The detection portion 51 abuts against the straight portion 41b of the wrist 27, preventing the detection portion 51 from shifting toward the second upper arm 26.

Then, while fastener 70 is threaded through connecting plate 82 of fastener 80, the tip of fastener 70 is pulled to remove any slack in fasteners 70, 80, bringing fasteners 70, 80 into contact with wrist portion 27 from the inside of the bent position. Then, the hook portion 71 and loop portion 72 (see Figure 3) of fastener 70 are connected to maintain this contact, bringing both fasteners 70, 80 into a connected state. This effectively prevents the detection unit 51 from shifting position or falling off the wrist portion 27 even if the fasteners 70, 80 are released (see Figure 6(d)).

After fasteners 70, 80 are joined, as shown in Figure 5(a), the restricting member 90 is screwed to the connecting plate 82, thereby sandwiching the fastener 70 between the connecting plate 82 and the restricting member 90. This prevents the fasteners 70, 80 from separating.

With this sensor unit 50, screws 95 are used to prevent the fasteners 70, 80 from separating. Therefore, when removing the sensor unit 50 from the wrist 27, the restricting member 90 is removed from the connecting plate 82 using a tool, not bare hands. After releasing the restriction on the fasteners 70, 80 from the separation, the connection between the hook portion 71 and loop portion 72 of the fastener 70 is released, and the fastener 70 is pulled out from the connecting plate 82. The connectors 44, 54 are then disconnected, and the cover 42 is returned to its original position, completing the procedure.

As described above in detail, if the outer bent portion of the wrist 27 (corresponding to the "predetermined link"), which has a bent middle portion, is covered with a planar detection unit 51, the wrist 27 can effectively detect contact with or approach to a person or other object. The links that make up the arm of an industrial robot are not necessarily linear; some are bent, like the wrist 27 shown in this embodiment. Although it is expected that such links will have stronger constraints on the mounting structure of the detection unit compared to linear links, being able to mount a planar detection unit 51 and expanding the monitoring range of the sensor unit 50 (the monitoring range of the arm 22) to include bent links is preferable in terms of minimizing the non-detection portion that does not detect contact, etc., and preventing missed detections.

Furthermore, the detection unit 51 shown in this embodiment can be easily positioned by covering the wrist portion 27 from the outside of the bent portion. The fasteners 70, 80 are then abutted against the inside of the bent portion 41c and coupled together, thereby wrapping the sensor unit 50 around the wrist portion 27. To remove the sensor unit 50, the restricting member 90 is removed by removing the screw 95 with a tool, releasing the restriction on the separation of the fasteners 70, 80. The fasteners 70, 80 are then separated (uncoupled), allowing for easy removal of the sensor unit 50. This configuration contributes to improved work efficiency during attachment and detachment. Industrial robots may be used in a variety of situations. For example, in collaborative situations, it is desirable to use the sensor unit 50 to enhance safety, but in non-collaborative situations, it is desirable to remove the sensor unit 50 to reduce loads and improve operational efficiency. In this regard, the present embodiment allows the sensor unit 50 to be attached or detached later, thereby enabling the robot 10 to be operated appropriately.

It cannot be denied that there is a possibility that an object may come into contact with the fasteners 70, 80, etc. while the robot 10 is operating. Furthermore, there is also a possibility that the user may accidentally touch the fasteners 70, 80, etc. when performing direct teaching, maintenance, or other tasks on the robot 10. This is particularly likely to occur when, for example, the fasteners 70, 80 or the restricting member 90 are located outside the detection unit 51 from the perspective of workability. Even if this occurs, the combined use of the fasteners 70, 80 and the restricting member 90 prevents the sensor unit 50 from easily falling off the wrist 27.

For the above reasons, the sensor unit 50 can be detached, allowing for proper operation of the robot 10 while contributing to improved reliability and workability when installing the sensor unit 50.

Since the restricting member 90 is positioned so that it is not covered by the detection unit 51, the detection unit 51 does not interfere with the attachment or detachment of the restricting member 90. This prevents the sensor unit 50 from falling off by using the fasteners 70, 80 and the restricting member 90 in combination, while preventing the restricting member 90 from becoming a factor that reduces the ease of attachment or detachment of the sensor unit 50.

Note that a configuration in which the restricting member 90 is positioned on the inside of the bend allows access to the restricting member 90 during attachment and detachment, while reducing the chance of an object hitting the restricting member 90 compared to a configuration in which the restricting member 90 is positioned on the outside of the bend. This is preferable in terms of preventing the restricting member 90 from interfering with detection and reducing the chance of the restriction by the restricting member 90 being accidentally released.

As shown in this embodiment, by configuring the overlapping portion of the blank portion 73 (corresponding to the "non-formed portion") to be clamped, crushing of the hook portion 71 and loop portion 72 can be avoided even if the fastener 70 is tightly clamped by the restricting member 90. This is preferable for improving durability when the sensor unit 50 is repeatedly attached and detached.

By fixing one end of the fasteners 70, 80 to the inside of the detection unit 51, away from the edge 55 of the side portions 56, 57 of the detection unit 51, distortion of the detection unit 51 is less likely to occur even when the fasteners 70, 80 are tightened when attaching the sensor unit 50 to a smaller link.

Next, with reference to Figures 7 to 10, a sensor unit applied to a straight section will be described using the sensor unit 100 for the first upper arm section 25 as an example.

As shown in FIG. 7, the first upper arm portion 25 is also bent at a midpoint, similar to the wrist portion 27. That is, the first upper arm portion 25 is composed of a straight portion 45a that connects to the lower arm portion 24 and extends in the same direction as the connecting axis AX3, a straight portion 45b that connects to the second upper arm portion 26 and extends in the same direction as the connecting axis AX4, and a bent portion 45c that connects the straight portions 45a and 45b. However, a major difference is that while the bent portion 41c of the wrist portion 27 makes up the majority of the wrist portion 27, the straight portion 45b of the first upper arm portion 25 makes up the majority of the first upper arm portion 25.

The sensor unit 100 has a pair of left and right detection sections 101 arranged side by side in the circumferential direction of the straight section 45b. Each detection section 101 is semi-cylindrical and is assembled so that the detection sections 101 sandwich the straight section 45b from the left and right. The detection section 101 is composed of a base frame 102 made of hard resin (e.g., polycarbonate) that faces the circumferential surface of the straight section 45b and a cover 103 made of soft resin (e.g., silicone) that covers the outer surface of the base frame 102. A sheet-like pressure sensor (not shown) is housed between the base frame 102 and the cover 103. When an object such as a person hits the cover 103, the cover 103 deforms, and the deformed cover 103 presses against the pressure sensor. This outputs a signal indicating contact with the object.

In this embodiment, the straight portion 45b is covered (surrounded) by two detectors aligned in the circumferential direction of the straight portion 45b, but the number of detectors is arbitrary. For example, the straight portion 45b may be covered (surrounded) by three detectors, or by four detectors. The detectors 101 may also be combined in any direction; for example, the straight portion 45b may be covered (surrounded) by a pair of upper and lower detectors.

Here, referring to Figure 8, we will provide additional explanation of the relationship between the pair of detection units 101. When the detection units 101 are attached to the linear portion 45b via the holder 120, the edges 108 of the detection units 101 face each other at the upper and lower sides of the linear portion 45b. In this state, a gap is created at the boundary BP between the opposing edges 108, exposing a portion of the linear portion 45b from the boundary BP. The boundary BP extends in the longitudinal direction of the linear portion 45b, and although the gap at the boundary BP is partially enlarged in the longitudinal direction, most of it is large enough that a finger cannot be inserted. In other words, even if an object such as a user's hand accidentally approaches the boundary BP, it is expected that the user's hand will hit one of the detection units 101, effectively reducing the chance of a missed detection. Therefore, the presence of the boundary BP does not significantly reduce the monitoring function.

In the first upper arm section 25 shown in this embodiment, multiple operation buttons 25a are arranged above the straight section 45b to be operated by the user during direct teaching, etc. The operation buttons 25a are also aligned in the longitudinal direction of the straight section 45b, and all are accessible through the boundary section BP. More specifically, by partially expanding the boundary section BP, a decrease in the operability of the operation buttons 25a is avoided, while aligning the arrangement direction with the orientation of the boundary section BP prevents the boundary section BP from becoming excessively wide.

A portion of the holder 120 used to attach the detection unit 101 to the linear portion 45b is also visible through this boundary portion BP. Now, referring again to Figure 7, the mounting structure of the sensor unit 100 will be described. Both detection units 101 are attached to the linear portion 45b of the first upper arm portion 25 via annular holders 120. Specifically, the holder 120 is composed of a pair of upper and lower brackets 121 and a pair of left and right hook fasteners 122 that connect the brackets 121. The hook fasteners 122 are strip-shaped, and each end of the hook fastener 122 is formed with a hook portion and a loop portion that connects to the hook portion.

In this embodiment, the straight portion 45b is formed so that the cross section perpendicular to the longitudinal direction of the straight portion 45b is circular, and the bracket 121 has an arc-shaped base portion 131 that curves to fit the outer periphery of the straight portion 45b. As shown in FIG. 9 , slits 132 through which hook-and-loop fasteners 122 are inserted are formed at both ends (left and right ends) of the base portion 131. The hook-and-loop fasteners 122 are inserted into the slits 132 of the upper and lower brackets 121 to span the brackets 121, and the hook-and-loop fasteners 122 are folded back starting from each slit 132 to join the hook and loop portions, thereby forming an annular holder 120 with the pair of upper and lower brackets 121 and the pair of left and right hook-and-loop fasteners.

A bulge 135 is formed on the base 131 of the holder 120, bulging outward (away from the straight portion 45b). A recess 109 is formed on the edge 108 of the detection unit 101 to correspond to the bulge 135, partially expanding the boundary portion BP. By partially expanding the boundary portion BP with the recess 109, the portion of the boundary portion BP that is not covered by the detection unit 101 is prevented from increasing (see Figure 8). Note that the amount by which the bulge 135 protrudes from the circumferential surface of the straight portion 45b is smaller than the amount by which the detection unit 101 protrudes, thereby limiting protrusion from the recess 109.

The base frame 102 of the detection unit 101 has a semi-cylindrical frame body 105, and claw portions 106 are formed on the upper and lower ends of this frame body 105, specifically the portions where the recesses 109 are formed, so as to protrude inward. As shown in FIG. 10 , the bulging portion 135 is formed with claw receiving portions 136 onto which the claw portions 106 of both detection units 101 hook from the straight portion 45b side. The base portion 131 is formed with openings 133 that allow the claw portions 106 to approach the claw receiving portions 136 when the detection unit 101 is moved toward the bulging portion 135. The claw portions 106 hook onto the claw receiving portions 136, preventing the detection unit 101 from falling off.

When the detection unit 101 is attached to the holder 120, the hook-and-loop fastener 122 is covered by the detection unit 101. This prevents the hook-and-loop fastener 122 from accidentally being released and causing the detection unit 101 to fall off due to an object accidentally hitting or getting caught on the hook-and-loop fastener 122.

As described above, when the detection unit 101 is attached, the portion exposed from the detection unit 101 is limited to the bulge 135. In this embodiment, the bulge 135 is provided with a structure for releasing the engagement between the claw 106 and the claw receiver 136, thereby enabling the sensor unit 100 to be attached and detached. The structure related to the removal of the sensor unit 100 will be described below with reference to Figure 10.

A through-hole 137 is formed in the center of the bulge 135, and the claw receiving portion 136 is formed separately on either side of the through-hole 137 in the assembly direction of the detection unit 101. When the claw 106 is engaged with the claw receiving portion 136, the tip (free end) of the claw 106 protrudes into the through-hole 137. A tool can be inserted into this through-hole 137 to push the claw 106 so that its engagement with the claw receiving portion 136 becomes smaller. However, as already explained, because the bulge 135 is not covered by the detection unit 101, there is a possibility that not only an object may come into contact with it, but also that the user may touch it during direct teaching or maintenance work. While enlarging the through-hole 137 is preferable for clearly informing the user of the tool insertion location, it is undesirable for the user's finger to accidentally hit the claw 106. Furthermore, if two detection units 101 become detached at the same time, the detection units 101 may fall, which is undesirable as it could cause problems such as damage. Therefore, in this embodiment, partitions 138 are formed at the back of the through-holes 137 to separate the through-holes 137 for use by each claw 106. In other words, at the back of the through-holes 137, the tool insertion sections 139 are separated for each claw 106. This makes it possible to effectively prevent problems caused by simultaneous release. Furthermore, the partitions 138 prevent the user's fingers from hitting the claws 106, making it possible to effectively prevent the detection units 101 from accidentally falling off.

Here, with reference to Figures 11 and 12, the workflow for attaching and detaching the sensor unit 100 to the first upper arm portion 25 will be explained in the order of attachment → detachment.

When attaching the sensor unit 100 to the first upper arm portion 25, as shown in Figures 11(a) and 11(b), two holders 120 are set on the straight portion 45b, spaced apart in the longitudinal direction of the straight portion 45b. Specifically, each bracket 121 is positioned so that the protrusions formed on the inner surface of the bracket 121 fit into the alignment recesses formed in the straight portion 45b (see Figure 10). This aligns the bulges 135 of both holders 120 in the longitudinal direction of the straight portion 45b.

In this embodiment, the straight section 45b is slightly tapered so that its diameter decreases toward the tip of the arm 22, but the length can be easily adjusted using the hook-and-loop fastener 122, making it possible to easily share two holders 120.

After the holder 120 is set, the detection unit 101 is attached to the holder 120. Specifically, as shown in Figures 11(c) and 11(d), the positional relationship between the target bulge 135 and the claw 106 of the detection unit 101 being held in the hand is visually confirmed, and the claw 106 is guided toward the claw receiver 136. After the tip of the claw 106 enters the opening 133 leading to the claw receiver 136, the detection unit 101 is moved closer to the first upper arm 25, causing the claw 106 to bend and hook onto the claw receiver 136. After one detection unit 101 is attached, another detection unit 101 is attached in the same manner. However, the bulge 135 is not hidden by the already attached detection unit 101, and visual confirmation of the positional relationship between the claw 106 and the claw receiver 136 is not difficult.

Furthermore, after the installation of both detection units 101 is complete, it is possible to visually check through the through-holes 137 whether the claws 106 are hooked onto the claw receivers 136, which makes it less likely that the robot 10 will resume operation while the detection units 101 are not completely installed.

Next, to remove the detection unit 101, as shown in Figure 12, insert a tool into the insertion portion 139 and push the claw portion 106. This causes the claw portion 106 to bend and move away from the claw receiving portion 136. In this way, the engagement between the claw portion 106 and the claw receiving portion 136 is released, allowing the detection unit 101 to be removed.

With the configuration described above, by attaching the holder 120 to the linear portion 45b of the first upper arm portion 25 and attaching the detection units 101 to the holder 120, the linear portion 45b is covered by the detection units 101. By configuring the sensor unit 100 with a combination of multiple detection units 101, the linear portion 45b can be comfortably covered over a wide area. This is advantageous for expanding the monitoring range of the sensor unit 100 and reducing detection misses. Here, adjacent pairs of detection units 101 are attached to the bulge portion 135 of the holder 120. Because this bulge portion 135 is located at the boundary BP formed between the detection units 101, when installing the detection units 101, the positional relationship between the detection units 101 and the bulge portion 135 can be visually confirmed while installing the detection units 101. This reduces the likelihood of an incomplete installation of the detection units 101. In other words, the monitoring range of the sensor unit on the arm 22 can be widened while increasing the reliability of the detection unit attachment.

The installation directions of adjacent pairs of detectors 101 are opposite to each other, so when installing the detectors 101, the previously installed detector 101 does not interfere with the installation of the other detector 101.

As shown in this embodiment, by recessing the edge 108 of the detection unit 101 to form a recess 109, it is possible to minimize the gap at the boundary portion BP except for the area where the bulge 135 is located. This is advantageous for widening the monitoring range of the sensor unit and reducing detection misses.

In a configuration in which the bulge portion 135 is located at the boundary portion BP of the detection unit 101, the exposed bulge portion 135 creates the possibility of an object coming into contact with the bulge portion 135. In this regard, as shown in this embodiment, by preventing the bulge portion 135 from protruding from the boundary portion BP of the detection unit 101, it becomes easier to encourage an object heading toward the bulge portion 135 to first hit the detection unit 101. This prevents the presence of the bulge portion 135 from becoming a cause of missed detection.

A through-hole 137, which is a tool insertion hole, is formed in the center of the bulge 135, and there is a solid portion between the bulge 135 and the through-hole 137. This effectively prevents an operator looking at the bulge 135 from mistakenly identifying the gap between the detection unit 101 and the bulge 135 as a tool insertion point.

Widening the entrance of the through-hole 137 through which the tool is inserted is preferable in order to prevent the tip of the tool from slipping out of the entrance and hitting the detection unit 101, etc. Here, there is a possibility that the user may come into contact with the arm of the industrial robot when performing direct teaching, maintenance, etc. In the configuration shown in this embodiment, even if the fingers gripping the arm 22 hit the bulge 135, the partition 138 prevents access to the claw 106 (corresponding to the "locking portion"), preventing accidental release of the lock.

Second Embodiment
In the first embodiment, the flange 28 of the robot body 11 is provided with a plurality of connection terminals 28a for the end effector. Because the number of connection terminals 28a that can be prepared on the flange 28 is limited, it is anticipated that the connection terminals 28a may not be compatible with certain types of end effectors. Even if the connection terminals 28a are incompatible, the end effector can still be used by passing the cable outside the arm 22 rather than inside the arm 22. In this case, the arm 22 holds the intermediate portion of the cable extending from the end effector, thereby preventing the cable from flapping. One of the features of this embodiment is that, when used in conjunction with the configuration in which the outer periphery of the arm 22 is covered with the sensor unit group 12 as shown in the first embodiment, the sensor unit and the cable holding structure are devised to optimally coexist. This devise is described below with reference to FIGS. 13 and 14 .

As shown in FIG. 13 , the first upper arm section 25 has a boundary portion BP formed in the longitudinal direction of the first upper arm section 25 (straight portion) by the sensor unit 100 attached to the first upper arm section 25, specifically by a pair of left and right detection units 101. This boundary portion BP is an area not covered by the detection units 101, and is groove-shaped by the edge portion 108 of the detection units 101. Multiple cable holders 140 are arranged along this boundary portion BP on the first upper arm section 25. The cable holders 140 are fixed to a holder 120 that attaches the detection units 101 to the first upper arm section 25. Specifically, the cable holders 140 are fixed to bulges 135 of the holder 120 that are located at the boundary portion BP.

As shown in FIG. 14, the cable holder 140 comprises a base portion 141 that covers the bulge portion 135 from the side opposite the first upper arm portion 25, and a clamp portion 142 that stands upright from the base portion 141. The base portion 141 and the bulge portion 135 are screwed together and overlap each other. In other words, the base portion 141 prevents access to the claw portion 106.

The clamp portion 142 has an annular cable insertion portion into which the cable 145 is inserted, and holds the cable 145 inserted in this cable insertion portion. The central axis of the cable insertion portion is oriented in the longitudinal direction of the first upper arm portion 25, i.e., the same direction as the extension of the boundary portion BP. The cable 145 held by the clamp portions 142 extends along the boundary portion BP while deflection between the clamp portions 142 is suppressed (see Figure 13).

The cable holder 140 specifies the offset of the cable 145 from the circumferential surface of the first upper arm portion 25 so that the held cable 145 passes at a position away from the boundary portion BP, thereby increasing the distance from the detection unit 101 in both the vertical and horizontal directions.

Attaching both the sensor unit 100 and the cable 145 (corresponding to a "linear member") to the first upper arm section 25 can result in the following inconvenience. Specifically, the cable 145 may swing due to the robot 10's operation and come into contact with the detection unit 101. Such movement of the cable 145, which could detect contact with an object, may result in unnecessary protection stops and hinder productivity improvement. In this regard, in the configuration shown in this embodiment, the edges 108 of the pair of detection units 101 face each other across a gap, forming a boundary portion BP extending in the longitudinal direction of the first upper arm section 25. Multiple cable holders 140 that hold the cables 145 are arranged along the boundary portion BP. Positioning the cables 145 in accordance with the cable holders 140 allows the cables 145 to be aligned with the boundary portion BP. This prevents the cables 145 from coming into contact with the detection unit 101, even when the cables 145 swing due to the robot 10's operation. In this way, by expanding the monitoring range of the sensor unit while preventing contact between the detection unit 101 and the cable 145, it is possible to optimally achieve both safety and productivity for the robot 10.

The configuration shown in this embodiment makes it possible to increase the distance between the cable 145 and the detection unit 101 not only in the width direction of the boundary area BP but also in the height direction of the boundary area BP. This effectively reduces the chance of contact between the cable 145 and the detection unit 101.

Furthermore, because the cable 145 is held outside the gap at the boundary portion BP, the width of the gap (boundary portion BP) can be minimized to avoid the cable holder 140. This is advantageous for reducing missed detections.

By arranging the cable holder 140 on the holder 120 for attaching the detection unit 101 to the first upper arm unit 25, it becomes easier to align the detection unit 101 with the cable holder 140.

By configuring the cable holder 140 to cover the hooking point between the claw portion 106 and the claw receiving portion 136, it is possible to easily prevent the detection unit 101 from falling off due to an object hitting the claw portion 106, etc.

The boundary portion BP extends in the same direction as the longitudinal direction of the first upper arm portion 25 (straight portion). This configuration minimizes the number of cable holders 140, thereby increasing the monitoring range of the sensor unit 100.

Aligning the operation button 25a and cable holder 140 along the boundary portion BP is preferable in order to expand the monitoring range of the sensor unit.

<Other embodiments>
The present invention is not limited to the contents of the above-described embodiments, and may be implemented, for example, as follows. The following configurations may be applied individually to the above-described embodiments, or may be applied in combination with some or all of them. It is also possible to arbitrarily combine all or some of the various configurations shown in the above-described embodiments. In this case, it is preferable that the technical significance (effects to be achieved) of each configuration to be combined is ensured. The following configurations may be applied individually to a new configuration formed by combining the embodiments, or may be applied in combination with some or all of them.

- In the above embodiments, contact of an object is detected using a pressure sensor, but this is not limited to this. Alternatively, or in addition, it is also possible to detect the approach of an object using a capacitance sensor or the like.

- In the above embodiments, the fasteners 70, 80 are fixed to the base frame 52 at positions away from the edge 55 on the side portions 56, 57 of the detection unit 51. However, it is also possible to fix the fasteners 70, 80 to the base frame 52 at the edge 55 on the side portions 56, 57 of the detection unit 51.

- In the above embodiments, fastener 70 is connected to fastener 80 using a connecting plate 82, but it is also possible to use hook-and-loop fasteners for both fastener 70 and fastener 80 and connect them directly.

- In the above embodiments, the boundary portion BP of the detection unit 101 has a wide portion and a narrow portion, but this is not limited to this. The width of the boundary portion BP can also be constant. Also, while the boundary portion BP is configured to extend in the longitudinal direction of the linear portion 45b, this does not rule out a configuration in which the boundary portion BP extends in a direction intersecting the longitudinal direction of the linear portion 45b.

- In the above embodiments, the connecting plate 82 and the restricting member 90 sandwich the double-layered blank portion 73, but this is not limited to this. It is also possible for the connecting plate 82 and the restricting member 90 to sandwich the double-layered portion where the hook portion 71 and the loop portion 72 are joined.

In each of the above embodiments, if it is possible to prevent the fasteners 70, 80 from being released from their connection, it is not necessarily necessary to sandwich the fastener 70 between the connecting plate 82 and the restricting member 90. For example, it is possible to form a long hole extending in the longitudinal direction of the fasteners 70, 80 and insert a pin or the like into the long hole as a restricting member to prevent the connection from being released or to prevent the fastener 70 from coming loose.

- In the above embodiments, the detection unit 101 is held by the holder 120, but it is also possible to attach the detection unit 101 directly to the peripheral surface of the first upper arm portion 25 using a hook-and-loop fastener.

- In the above embodiments, the tool insertion portions 139 for each claw portion 106 are separated so that the engagement between the claw portion 106 and the claw receiving portion 136 can be released one by one using a tool, but this is not limited to this. As long as the engagement of each claw portion 106 can at least be released using a tool, it is also possible to make it possible to release the engagement of both claw portions 106 with a single operation.

- In the above embodiments, both the sensor units 50 and 100 are hollow to reduce the impact when an object comes into contact with them, but this is not limited to this. For example, the detection unit may be sheet-shaped.

- In the second embodiment described above, the "linear member" extending from the end effector 29 is assumed to be a cable 145 that transmits electrical signals, but this is not limited to this. For example, even in a configuration in which a tube extending from the end effector transmits a fluid such as air or oil, the holding structure using the cable holder 140 described above may be applied to the tube.

- In the second embodiment described above, the cable 145 is arranged along the boundary portion BP, but is not located within the boundary portion BP. However, this does not preclude a configuration in which the cable 145 is housed within the boundary portion BP.

- In the second embodiment described above, the cable holder 140 was fixed to the holder 120 for mounting the detection unit 101, but this may be changed so that the cable holder 140 is fixed to the peripheral surface of the first upper arm portion 25.

<Inventions extracted from the above embodiments>
The following describes the features of the inventions extracted from the above embodiments, while indicating, as necessary, their effects, etc. Note that, for ease of understanding, the corresponding configurations in the above embodiments are indicated in parentheses as appropriate, but the invention is not limited to the specific configurations indicated in parentheses.

<Feature A Group> Sensor unit for bending portion and its mounting structure The following feature A group is a description of the background art that states, "Some industrial robots, such as articulated robots, in which multiple links are connected in a series, are configured to be able to detect when a link comes into contact with an object (obstacle), such as a person. For example, the industrial robot described in Patent Document 1 (Japanese Patent Laid-Open Publication No. 2005-103674) has a detection function that detects contact based on the abnormal torque generated when the robot comes into contact with an object, and when contact is detected, the industrial robot is stopped (protective stop) to protect the industrial robot and the object." The same threshold value is used to determine abnormal torque regardless of the distance from the contact point to the joint. This results in differences in contact detection accuracy and responsiveness depending on the contact point. For example, detection accuracy and responsiveness are lower at positions closer to the joint than at positions further away. If the threshold value is lowered assuming contact at positions closer to the joint, production efficiency may decrease due to an increase in unnecessary protection stops. In contrast, if the surface of the arm (link) is covered with a sensor unit having a detection section that can detect contact with or approach to an object, the above-mentioned concerns about detection accuracy and responsiveness can be eliminated. When using this type of sensor unit, it is preferable to minimize the area on the arm surface where the sensor unit is not located, i.e., the non-detecting area that does not detect contact, etc. Furthermore, industrial robots may be used in a variety of situations, and allowing the sensor unit to be attached or detached later allows for proper operation of the industrial robot. For example, while using a sensor unit to enhance safety in collaborative situations is preferable, removing the sensor unit in non-collaborative situations is preferable to reduce load and improve operational efficiency. Here, the links constituting the arm are not necessarily linear; some are bent at their midpoints to form an L-shape (e.g., a bent portion). It is expected that links with bent portions have stronger constraints on the sensor unit mounting structure, etc., compared to linear links. In other words, there is still room for improvement in the configuration of the sensor unit and its mounting structure in order to enable the appropriate operation of industrial robots by allowing the sensor unit to be attached or detached, while improving the reliability and operability of the sensor unit mounting. This was developed in consideration of the following background and challenges.

Feature A1: A sensor unit (sensor unit 50) applicable to an industrial robot having an arm (arm 22) in which a plurality of links (shoulder portion 23, lower arm portion 24, first upper arm portion 25, second upper arm portion 26, wrist portion 27, flange portion 28) are connected in a series, including a predetermined link (e.g., wrist portion 27) having a bent portion (bent portion 41c) formed in the middle portion,
a planar detection unit (detection unit 51) capable of detecting at least one of contact with an object and approach to an object, the planar detection unit covering an outer side of the bent portion;
fasteners (fasteners 70, 80) that are provided on the sides of the bent portion of the detection unit and that face each other across the bent portion (side portions 56, 57), respectively, and that allow the detection unit to be attached to and detached from the predetermined link;
At least one of the fasteners abuts on a portion of the bent portion that is on the inner side of the bent portion, and the fasteners are connected to each other, thereby preventing the detection unit from falling off the predetermined link,
A sensor unit having a regulating section (regulating member 90 and screw 95) configured to regulate the separation of the fasteners in the coupled state and to release the regulation when a specified release operation (removal operation using a tool) is performed.

As shown in this feature, if a specified link with a bent middle section is configured so that the outer portion of the bend is covered with a planar detection unit, contact with or approach to a person or other object can be suitably detected at the specified link. The links that make up the arm of an industrial robot are not necessarily straight; some are bent like the specified link shown in this feature. Although it is expected that such links will have stronger constraints on the mounting structure of the sensor unit (detection unit) compared to straight links, being able to mount a planar detection unit and expanding the monitoring range of the sensor unit (monitoring range of the arm) to include bent links is preferable in terms of minimizing the non-detection portion that does not detect contact, etc., and preventing missed detections.

Furthermore, with this configuration, the detection unit can be easily positioned by covering the outer side of the bend with the designated link. The fastener is then abutted against the inner side of the bend and coupled, resulting in the sensor unit being wrapped around the designated link. On the other hand, when removing the sensor unit, the restriction on separation of the fastener imposed by the restricting unit is released by a specified release operation, and the fastener is separated (uncoupled), allowing the sensor unit to be easily removed. This configuration contributes to improved work efficiency when performing attachment and detachment. Industrial robots may be used in a variety of situations. For example, in collaborative situations, it is desirable to use a sensor unit to enhance safety, but in non-collaborative situations, it is preferable to remove the sensor unit to reduce load and improve operational efficiency. In this regard, the configuration with this configuration allows the sensor unit (detection unit) to be attached or detached later, enabling the industrial robot to be operated appropriately.

It cannot be denied that there is a possibility that an object may come into contact with a fastener or other device while an industrial robot is operating. Furthermore, with industrial robots, there is also the possibility that a user may accidentally touch a fastener or other device during tasks such as direct teaching or maintenance. This is particularly likely to occur when, from an operational standpoint, fasteners or restricting units are located outside the sensor unit. Even if this occurs, the use of both fasteners and restricting units prevents the sensor unit from easily falling off the designated link.

For the above reasons, the sensor unit can be detached, enabling proper operation of the industrial robot while contributing to improved reliability and workability when installing the sensor unit.

Feature A2: The detection unit is configured not to cover at least a part of the inner side of the bending portion,
The sensor unit according to feature A1, wherein the restricting portion is positioned on the inner side of the bent portion and not covered by the detecting portion.

The restricting part is positioned so that it is not covered by the detecting part, preventing the detecting part from interfering with the work of attaching and detaching the restricting part. This prevents the sensor unit from falling off by using the fastener and restricting part together, while preventing the restricting part from becoming a factor that reduces the ease of attaching and detaching the sensor unit.

Note that a configuration in which the restricting portion is located on the inside of the bend allows access to the restricting portion during attachment and detachment, while reducing the chance of an object hitting the restricting portion compared to a configuration in which the restricting portion is located on the outside of the bend. This is preferable in terms of preventing the restricting portion from interfering with detection and reducing the chance of the restriction by the restricting portion being accidentally released.

Feature A3: The predetermined link has a first linear portion (linear portion 41 a) continuing from one end of the bent portion and a second linear portion (linear portion 41 b) continuing from the other end of the bent portion, and is an L-shaped link as a whole;
The sensor unit according to Feature A1 or Feature A2, wherein the detection section is formed so as to cover at least a portion of the first straight section and at least a portion of the second straight section from the outer side of the bend.

In a configuration in which the detection unit is secured after being placed over a specified link, the detection unit may shift position during the securing process using a fastener, requiring the work to be redone. Furthermore, if the detection unit is secured while still misaligned, there is a concern that its detection function may not function properly. In this regard, with this characteristic configuration, the detection unit contacts the first straight portion of the specified link, thereby preventing misalignment toward the second straight portion, and the detection unit contacts the second straight portion of the specified link, thereby preventing misalignment toward the first straight portion. In this way, providing the detection unit with the ability to prevent its own misalignment contributes to improved workability and reliability during the securing process. Furthermore, using a restricting section to more reliably prevent the sensor unit from falling off also helps prevent the increased work time required for attaching and detaching the sensor unit.

Feature A4: The fastener is composed of a belt-shaped first fastener (fastener 70) and a second fastener (fastener 80) having an insertion portion (opening 83) through which the first fastener is inserted, and in the coupled state, the first fastener is folded back from the insertion portion to form a double fastener.
A sensor unit according to any one of features A1 to A3, wherein the regulating portion regulates the separation by pinching the doubled portion of the first fastener in the overlapping direction.

By configuring the belt-shaped first fastener so that it is folded back starting from the insertion portion and doubled over, it is possible to effectively prevent the first fastener from slipping out of the insertion portion.

Feature A5. The first fastener is a hook-and-loop fastener having a first coupling portion (hook portion 71) and a second coupling portion (loop portion 72) that can be coupled to the first coupling portion formed on a surface thereof,
When the first fastener is inserted into the insertion portion, the first coupling portion and the second coupling portion are coupled together, so that both fasteners are in the coupled state,
The overlapping portion includes an overlapping portion of a non-formed portion (blank portion 73) in which neither the first connecting portion nor the second connecting portion is formed in the first fastener,
The sensor unit according to Feature A4, wherein the restricting portion is configured to sandwich the overlapping portion of the non-forming portion.

As shown in this feature, by configuring the overlapping portion of the non-forming portion to be clamped, crushing of the first connecting portion and the second connecting portion can be avoided even if the first fastener is tightly clamped by the restricting portion. This is preferable for improving durability when the sensor unit is repeatedly attached and detached.

Feature A6. The first fastener is a hook-and-loop fastener having a first coupling portion (hook portion 71) and a second coupling portion (loop portion 72) that can be coupled to the first coupling portion formed on a surface thereof,
When the first fastener is inserted into the insertion portion, the first coupling portion and the second coupling portion are coupled together, so that both fasteners are in the coupled state,
The sensor unit according to Feature A4, wherein the regulating portion is configured to sandwich the overlapping portion of the first connecting portion and the second connecting portion.

By using a configuration in which the overlapping portion (joining point) of the first and second joining portions is sandwiched between restricting portions, the joining can be supported by the restricting portions. Even if the joining strength weakens due to repeated attachment and detachment, the support provided by the restricting portions can prevent the parts from easily separating.

Feature A7. The restriction portion is capable of being fixed to the second fastener,
A sensor unit described in any one of features A4 to A6, which is configured to sandwich the double portion of the first fastener between the second fastener and the regulating portion fixed to the second fastener.

By configuring the first fastener to be clamped between the restricting portion and the second fastener, the labor required can be reduced compared to, for example, a configuration in which the first fastener is clamped by the restricting portion alone and then the restricting portion is fixed to the second fastener, etc.

Feature A8. The second fastener and the restriction portion are fixed with a screw,
The sensor unit according to feature A7, wherein the restriction is released by removing the screw through the predetermined release operation.

As mentioned above, with industrial robots, there is a possibility that an operator may come into contact with the arm during direct teaching, maintenance, etc. Such work is often performed with bare hands, so even if an operator were to touch the restricting part, the possibility of the screw coming loose by accident is low. This effectively prevents the sensor unit from falling off.

Feature A9. A sensor unit as described in Feature A8, wherein the restricting portion and the second fastener have a hole for the screw formed therein so as to communicate with the second fastener and the restricting portion when the restricting portion and the fastener are overlapped in the overlapping direction.

This characteristic configuration allows the restricting portion to press the belt by tightening the screw. This configuration effectively prevents the belt from slipping between the restricting portion and the second fastener.

Feature A10. At least one of the fasteners has a belt,
A sensor unit according to any one of features A1 to A9, wherein one end of the belt is fixed to an inner portion of the detection unit, away from the edge of the opposing portion of the detection unit.

If the fastener is a belt, it can tolerate a certain degree of size variation in the bending links. Here, as shown in this feature, by fixing one end of the belt to the inside of the detection unit, away from the edge of the opposing part of the detection unit, distortion in the detection unit is less likely to occur even when the fastener is tightened when the links are small.

Feature A11. At least one of the fasteners comprises a belt;
The sensor unit according to any one of Features A1 to A9, wherein one end of the belt is fixed to an edge of the opposing portion of the detection unit.

If the fastener is a belt, it can accommodate a certain degree of size variation in the bending links. Here, as shown in this feature, if one end of the belt is fixed to the edge of the opposing part of the detection unit, it becomes easier to make the detection unit follow the surface of the link when the fastener is tightened.

Feature A12. An industrial robot equipped with a sensor unit described in any one of Features A1 to A11.

The detachable sensor unit allows for proper operation of the industrial robot, while also contributing to improved reliability and workability when installing the sensor unit.

<Feature B group> Sensor unit for straight section and mounting structure thereof Feature B group below is a description of the background art that states, "Some industrial robots, such as articulated robots in which multiple links are connected in a series, are configured to be able to detect when a link comes into contact with an object (obstacle), such as a person. For example, the industrial robot described in Patent Document 1 (Japanese Patent Laid-Open Publication No. 2005-103674) has a detection function that detects contact based on the abnormal torque generated when it comes into contact with an object, and when contact is detected, the industrial robot is stopped (protection stop) to protect the industrial robot and the object." The description states, "In the detection method described above, the same threshold value is used to determine abnormal torque regardless of the distance from the point of contact with the object to the joint. For this reason, differences occur in the accuracy and responsiveness of contact detection depending on the point of contact. For example, the detection accuracy and responsiveness are lower at positions close to the joint compared to positions farther away. Note that if the threshold value is lowered assuming contact at a position close to the joint, the number of unnecessary protection stops increases, which may result in a decrease in production efficiency. In contrast, a sensor having a detection unit that detects contact with or approaching an object If the sensor unit covers the surface of the arm (link), the above-mentioned concerns about detection accuracy and responsiveness can be eliminated. When using this type of sensor unit, it is preferable to minimize the area on the arm surface where the detection unit is not located, i.e., the non-detecting area that does not detect contact, etc. On the other hand, minimizing the non-detecting area imposes strict restrictions on the mounting structure of the detection unit, potentially making the arm-side mounting structure (the mounting portion for the detection unit) difficult to see, hidden by the detection unit. In other words, it is expected that the workability of mounting the detection unit will be reduced. This is undesirable because it could lead to work errors such as incomplete mounting of the detection unit. Furthermore, there is a concern that the above-mentioned protective function will not be properly performed if the industrial robot operates with the detection unit incompletely mounted. Thus, there is still room for improvement in the configuration of the sensor unit in order to increase the area of the arm covered by the detection unit, i.e., the monitoring range of the sensor unit, while increasing the reliability of the sensor unit mounting. This was developed in consideration of the background and issues described above.

Feature B1: A sensor unit (sensor unit 100) applicable to an industrial robot having an arm (arm 22) in which a plurality of links (shoulder portion 23, lower arm portion 24, first upper arm portion 25, second upper arm portion 26, wrist portion 27, flange portion 28) are connected in a series, including a predetermined link (first upper arm portion 25) formed so that at least a portion thereof is a straight portion (straight portion 45b),
a plurality of detection units (detection units 101) that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member (holder 120) attached to the predetermined link and having mounting portions (bulges 135) to which a pair of adjacent detection units among the plurality of detection units are attached;
The sensor unit is configured so that the attachment portion of the holder member is positioned at a boundary portion (boundary portion BP) between the pair of adjacent detection portions.

With this configuration, a holder member is attached to a predetermined link, and detectors are attached to the holder member, covering the predetermined link. By configuring the sensor unit as a combination of multiple detectors, a wide area of the predetermined link can be comfortably covered. This is advantageous for widening the monitoring range of the sensor unit and reducing detection misses. Adjacent pairs of detectors are attached to the mounting portions of the holder member. Because these mounting portions are located at the boundary between the detectors, the positional relationship between the detectors and the mounting portions can be visually confirmed during installation of the detectors. This reduces the likelihood of operational errors, such as incomplete installation of the detectors. In other words, the monitoring range of the sensor unit on the arm can be widened while increasing the reliability of sensor unit installation.

Feature B2. A sensor unit according to Feature B1, in which the mounting directions of the adjacent pairs of detection units are opposite to each other.

This characteristic configuration prevents one of the detectors installed first from interfering with the installation of the other detector when installing a pair of adjacent detectors.

Feature B3. A sensor unit as described in Feature B1 or Feature B2, in which a recess (recess 109) is formed by recessing a portion of the edge (edge 108) facing each other across the boundary portion of the pair of adjacent detection units, and when the detection units are attached, the attachment unit is located in a position surrounded by the recess.

By setting back the edge to form a recess, as shown in this feature, it is possible to minimize gaps at the boundary except where the mounting part is located. This is advantageous for expanding the monitoring range of the sensor unit and reducing missed detections.

For example, it is preferable that the mounting portion is located at a position surrounded by a recess formed in one detection portion and a recess formed in another detection portion.

Feature B4. A sensor unit according to any one of Features B1 to B3, wherein the mounting portion is formed so that the amount of protrusion from the outer peripheral surface of the linear portion is smaller than the amount of overhang of the detection portion from the outer peripheral surface.

As shown in Feature B1, in a configuration in which the attachment part is located at the boundary of the detection part, the exposed attachment part creates the possibility of an object coming into contact with the attachment part. In this regard, as shown in this feature, by preventing the attachment part from protruding from the boundary of the detection part, it becomes easier to encourage an object heading towards the attachment part to first hit the detection part. This prevents the presence of the attachment part from becoming a cause of missed detection. Furthermore, the configuration shown in this feature reduces the opportunity for contact with the attachment part, which is preferable for preventing the detection part from being accidentally released from its attachment.

Feature B5: The holder member includes a bracket (bracket 121) on which the attachment portion is formed, and a band (hook-and-loop fastener 122) that prevents the bracket from falling off the link,
The sensor unit according to any one of Features B1 to B4, wherein the band is covered by the detection section when the detection section is attached to the attachment section.

As shown in this feature, by configuring the band so that it is covered (hidden) by the detection unit, the chances of a user accidentally touching the band can be reduced. This is preferable for preventing the band from accidentally coming off and the detection unit from falling off.

Feature B6. The band is a hook-and-loop fastener;
The sensor unit according to Feature B5, wherein when the detection section is attached to the attachment section, the detection section faces the connecting portion of the hook-and-loop fastener in the connecting direction.

This characteristic configuration allows the detection unit to prevent the hook-and-loop fastener from separating. For example, the frame of the detection unit (base frame 102) can be brought into contact with the fastening point of the hook-and-loop fastener.

Feature B7: The boundary portion between the pair of adjacent detection units extends in the same direction as the longitudinal direction of the linear portion,
a plurality of the attachment portions are arranged along the boundary portion,
The sensor unit according to any one of Features B1 to B6, wherein the pair of adjacent detection units are both attached to the respective attachment portions.

Attaching each detector to multiple mounting points is preferable in terms of preventing the detectors from falling off or shifting position, but there are concerns that increasing the number of mounting points will make the installation process more difficult. In this regard, as shown in this feature, by configuring the boundary portions to extend in the same direction as the longitudinal direction of the straight portion of a given link and arranging the mounting points along these boundary portions, installation can be performed while visually checking each mounting point. Therefore, the effects described above can be achieved while minimizing any reduction in workability.

Feature B8. A sensor unit according to any one of Features B1 to B7, wherein the mounting portion has a central insertion hole (through hole 137) through which a removal tool is inserted when removing the detection unit from the mounting portion.

When removing the detection unit, a tool is inserted into the insertion hole. By locating this insertion hole in the center of the mounting part, the tool is prevented from coming into contact with the detection unit, helping to protect the detection unit.

Feature B9: The detection unit has a locking portion (claw portion 106) formed thereon,
A sensor unit as described in feature B8, in which the detection unit is attached to the mounting portion by the engaging portion hooking onto the flesh portion (claw receiving portion 136) between the insertion hole and the detection unit in the mounting portion.

This feature of the configuration effectively prevents a worker looking at the attachment part from mistakenly identifying the gap between the detection unit and the attachment part as the insertion point for a tool by forming a tool insertion hole in the central portion and providing a solid portion between the attachment part and the insertion hole.

Feature B10. A sensor unit as described in Feature B8 or Feature B9, in which the insertion hole has a hole portion (insertion portion 139) for one of the pair of adjacent detection portions and a hole portion (insertion portion 139) for the other detection portion, the entrance to the insertion hole is formed across these hole portions, and a partition portion (partition portion 138) separating the two hole portions prevents difficulty in inserting a finger into each hole portion.

Widening the entrance to the insertion hole is preferable to prevent the tool tip from slipping out of the entrance and hitting the detection unit, etc. Here, there is a possibility that the user may touch the arm of an industrial robot when performing direct teaching, maintenance, etc. With this characteristic configuration, even if the fingers grasping the arm hit the mounting unit, the partition prevents access to the locking unit, preventing accidental release of the lock.

Feature B11. An industrial robot equipped with a sensor unit described in any one of Features B1 to B11.

This increases the area of the arm covered by the detection unit while also increasing the reliability of installation of the detection unit (sensor unit).

Feature B12 (Claim Up Main Claim Mounting Structure) This is a mounting structure that is applied to an industrial robot having an arm (arm 22) in which a plurality of links (shoulder portion 23, lower arm portion 24, first upper arm portion 25, second upper arm portion 26, wrist portion 27, flange portion 28) are connected in a series, including a predetermined link (first upper arm portion 25) formed so that at least a portion thereof is a straight portion (straight portion 45b), and that mounts a sensor unit (sensor unit 100) to the straight portion of the predetermined link.
the sensor unit includes a plurality of detection units (detection units 101) that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member (holder 120) attached to the arm and having mounting portions (bulges 135) to which a pair of adjacent detection units among the plurality of detection units are attached;
The mounting structure is configured so that the mounting portion of the holder member is positioned at a boundary portion (boundary portion BP) between the pair of adjacent detection portions.

This characteristic configuration increases the area of the arm covered by the detection unit while also improving the reliability of installation of the detection unit (sensor unit).

<Feature C Group> Holding structure for end effector cable The following feature C group is related to the background art that states, "Some industrial robots, such as articulated robots, in which multiple links are connected in a series, are configured to be able to detect when a link comes into contact with an object (obstacle), such as a person. For example, the industrial robot described in Patent Document 1 (Japanese Patent Laid-Open Publication No. 2005-103674) has a detection function that detects contact based on abnormal torque generated when the robot comes into contact with an object, and when contact is detected, the industrial robot is stopped (protection stop) to protect the industrial robot and the object." The above-mentioned detection method uses the same threshold value regardless of the distance from the point of contact with the object to the joint. Abnormal torque is determined by the sensor. For this reason, differences occur in the accuracy and responsiveness of contact detection depending on the contact location. For example, detection accuracy and responsiveness are lower at positions closer to the joint than at positions further away. If the threshold is lowered assuming contact at positions closer to the joint, production efficiency may decrease due to an increase in unnecessary protection stops. In contrast, if the surface of the arm (link) is covered with a sensor unit having a detection part that detects contact with or approach to an object, the above-mentioned concerns about detection accuracy and responsiveness can be eliminated. When using this type of sensor unit, it is necessary to cover the parts of the arm surface where the detection part is not located, i.e., the parts that do not detect contact, etc. It is preferable to minimize the non-detection portion where the detection is not possible. Here, an end effector such as a hand is attached to the tip of the arm, and by making the end effector interchangeable depending on the type of work, the convenience of the industrial robot is improved. One end of a member such as a tube or cable (hereinafter referred to as a linear member) is connected to the end effector. The end effector is driven by sending a fluid or a signal via this linear member. When the linear member is arranged along the surface (outer surface) of the arm, the linear member can be held by the arm, thereby reducing the chance that a worker or the like will get caught on the linear member. Note that arranging the holding point on the surface of the arm This is advantageous in that it makes it easy to attach and detach the linear member when replacing the end effector. However, if both the sensor unit and the linear member described above are attached to the arm, the following inconvenience may occur. That is, the linear member may swing due to the operation of the industrial robot and come into contact with or approach the detection unit. There is a concern that such movement of the linear member, which may detect contact with an object, may cause unnecessary protection stops and hinder productivity improvement. As such, there is still room for improvement in the holding structure (mounting structure) of the sensor unit and the linear member in order to achieve both safety and productivity of industrial robots. This was made in consideration of the background and issues mentioned above.

Feature C1. A holding structure applicable to an industrial robot having an arm (arm 22) in which a plurality of links (shoulder portion 23, lower arm portion 24, first upper arm portion 25, second upper arm portion 26, wrist portion 27, flange portion 28) including a predetermined link (first upper arm portion 25) are connected in series, and in which a sensor unit capable of detecting at least one of contact with and proximity to an object is attached to the predetermined link, in which a linear member (cable 145) extending from an end effector (end effector 29) attached to the tip of the arm is held by the arm,
The sensor unit has a plurality of detection units (detection units 101) arranged in a circumferential direction of the predetermined link, and the predetermined link is covered by the detection units.
edge portions (edge portions 108) of a pair of adjacent detection portions among the plurality of detection portions face each other across a gap, thereby forming a boundary portion (boundary portion BP) extending in the longitudinal direction of the predetermined link,
A holding structure in which a plurality of holding portions (cable holders 140) for holding the linear members are arranged along the boundary portion.

Linear members such as tubes and cables are connected to end effectors, such as hands, attached to the ends of industrial robot arms. By holding these linear members with the arm, the chances of workers or others getting caught on the linear members can be reduced.

Furthermore, by configuring the sensor unit as a combination of multiple detection units, it is possible to comfortably cover a wide area of a given link. This is advantageous for widening the monitoring range of the sensor unit and reducing missed detections.

However, if both the sensor unit and the linear member are attached to the arm (a specified link), the following inconvenience may occur. Specifically, the linear member may swing due to the operation of the industrial robot and come into contact with or approach the detection unit. Such detection of contact with an object due to the movement of the linear member may result in unnecessary protection stops and hinder productivity improvement. In this regard, with this characteristic configuration, the edges of a pair of adjacent detection units face each other across a gap, forming a boundary extending in the longitudinal direction of the specified link. Multiple holding units that hold the linear member are arranged along this boundary. By aligning the linear member with the holding units, the linear member can be aligned with the boundary. This prevents the linear member from hitting the detection unit even if it swings due to the operation of the industrial robot. In this way, by expanding the monitoring range of the sensor unit while preventing contact between the detection unit of the sensor unit and the linear member, it is possible to achieve both safety and productivity of the industrial robot.

Feature C2. A holding structure according to Feature C1, in which the holding portion holds the linear member at a position offset from the surface of the specified link.

This characteristic configuration allows for increased distance between the linear member and the detection unit not only in the width direction of the boundary but also in the height direction of the boundary. This effectively reduces the chance of contact between the linear member and the detection unit.

Feature C3. A holding structure according to Feature C1 or Feature C2, in which the holding portion is capable of holding the linear member outside the gap in the boundary portion.

As shown in this feature, by holding the linear member outside the gap, the width of the gap (boundary portion) can be made as small as possible to avoid the holding portion. This is preferable for reducing missed detections.

Feature C4: The sensor unit has a holder member (holder 120) that is attached by being wrapped around the predetermined link, and the detection unit is attached to this holder member,
The holding structure according to any one of Features C1 to C3, wherein the holding portion is disposed in a portion of the holder member that is located at the boundary portion.

As shown in this feature, by arranging a holding portion on the holder member for the mounting portion, it becomes easier to align the detection unit and holding portion.

Feature C5: The holder member is formed with a receiving portion (claw receiving portion 136) to which a locking portion (claw portion 106) provided on the detection unit is locked, and the detection unit is attached to the holder member by the locking portion being locked to the receiving portion,
The holding structure according to feature C4, wherein an engaging portion between the engaging portion and the receiving portion is covered by the holding portion.

As shown in this feature, by configuring the retaining part to cover the engaging point between the locking part and the receiving part, it is possible to easily prevent the detection part from falling off due to an object hitting the locking part, etc.

Feature C6. An industrial robot having a holding structure described in any one of Features C1 to C5.

This allows for an optimal balance between safety and productivity for industrial robots.

Feature C7. An arm (arm 22) in which a plurality of links (shoulder portion 23, lower arm portion 24, first upper arm portion 25, second upper arm portion 26, wrist portion 27, flange portion 28) including a predetermined link (first upper arm portion 25) are connected in a series,
a sensor unit (sensor unit 100) attached to the arm and capable of detecting at least one of contact with an object and proximity to an object;
an end effector (end effector 29) attached to the tip of the arm; and a holding portion (cable holder 140) that holds, with the arm, a linear member (cable 145) extending from the end effector (end effector 29),
The sensor unit has a plurality of detection units (detection units 101) arranged in a circumferential direction of the predetermined link, and the predetermined link is covered by the detection units.
a boundary portion (boundary portion BP) extending in the longitudinal direction of the predetermined link is formed by edges of a pair of adjacent detection portions among the plurality of detection portions facing each other across a gap,
The holding portion is disposed at the boundary portion, and the linear member is held by the holding portion so as to be positioned along the boundary portion.

This configuration, which demonstrates these characteristics, expands the monitoring range of the sensor unit while preventing contact between the sensor unit's detection part and linear members, thereby achieving an optimal balance between safety and productivity for industrial robots.

Feature C8. An industrial robot according to Feature C7, wherein the boundary portion extends in the same direction as the longitudinal direction of the straight portion of the specified link.

This characteristic configuration minimizes the number of holders, thereby increasing the monitoring range of the sensor unit.

Feature C9. The predetermined link has a linear portion (linear portion 45b) that is linear,
The industrial robot according to Feature C8, wherein the boundary portion extends across both ends of the straight portion.

According to this characteristic configuration, the boundary portion extends across both ends of the straight portion. This configuration allows the length of the boundary portion to be kept short. This reduces the number of holding parts required to position the linear member along the boundary portion. Furthermore, compared to a configuration in which the boundary portion changes three-dimensionally, for example by being curved, this configuration is advantageous in reducing the number of holding parts required to position the linear member.

Feature C10: The predetermined link has an operation button (operation button 25a) that is operated by the user,
The industrial robot according to any one of Features C7 to C9, wherein the operation button and the holding portion are located in the boundary portion and are arranged along the boundary portion.

Arranging the operation buttons and holders along the boundary is preferable in order to expand the monitoring range of the sensor unit.

10...Robot, 11...Robot main body, 12...Sensor unit group, 22...Arm, 25-28...Links, 29...End effector, 41c...Bent portion, 45b...Straight portion, 50...Sensor unit, 51...Detection portion, 56, 57...Side portion, 70...First fastener, 80...Second fastener, 82...Connecting plate, 90...Regulating member, 95...Screw, 100...Sensor unit, 101...Detection portion, 106...Claw portion, 108...Edge portion, 109...Recess, 120...Holder, 121...Bracket, 122...Velcro fastener, 135...Mounting portion, 136...Receiving portion, 137...Through hole, 138...Partition portion, 139...Insertion portion, 140...Cable holder, 145...Cable, BP...Boundary portion.

Claims (7)

A sensor unit applied to an industrial robot having an arm in which a plurality of links, including a predetermined link formed so that at least a portion thereof is a straight line, are connected in a series,
a plurality of detectors that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member attached to the predetermined link and having mounting portions to which a pair of adjacent detection units among the plurality of detection units are attached;
the attachment portion of the holder member is configured to be located at a boundary portion between the pair of adjacent detection portions ,
In the pair of adjacent detection parts, a recess is formed in the edge parts facing each other across the boundary part, by retracting a part of the edge part, and when the detection parts are attached, the attachment part is located at a position surrounded by the recess . A sensor unit applied to an industrial robot having an arm in which a plurality of links, including a predetermined link formed so that at least a portion thereof is a straight line, are connected in a series,
a plurality of detectors that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member attached to the predetermined link and having mounting portions to which a pair of adjacent detection units among the plurality of detection units are attached;
the attachment portion of the holder member is configured to be located at a boundary portion between the pair of adjacent detection portions ,
The sensor unit is configured such that the amount of protrusion of the mounting portion from the outer peripheral surface of the linear portion is smaller than the amount of protrusion of the detection portion from the outer peripheral surface . A sensor unit applied to an industrial robot having an arm in which a plurality of links, including a predetermined link formed so that at least a portion thereof is a straight line, are connected in a series,
a plurality of detectors that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member attached to the predetermined link and having mounting portions to which a pair of adjacent detection units among the plurality of detection units are attached;
the attachment portion of the holder member is configured to be located at a boundary portion between the pair of adjacent detection portions ,
the holder member includes a bracket on which the attachment portion is formed and a band that prevents the bracket from falling off the link,
The sensor unit has a detection section attached to the attachment section, whereby the band is covered by the detection section . A sensor unit applied to an industrial robot having an arm in which a plurality of links, including a predetermined link formed so that at least a portion thereof is a straight line, are connected in a series,
a plurality of detectors that are capable of detecting at least one of contact with an object and approach to an object, and that are arranged in a circumferential direction of the straight portion of the predetermined link and cover the straight portion;
a holder member attached to the predetermined link and having mounting portions to which a pair of adjacent detection units among the plurality of detection units are attached;
the attachment portion of the holder member is configured to be located at a boundary portion between the pair of adjacent detection portions ,
an insertion hole into which a removal tool is inserted when performing a removal operation to remove the detection unit from the mounting part is formed in a central part of the mounting part;
The insertion hole has a hole portion for one of the pair of adjacent detection units and a hole portion for the other detection unit, and the entrance to the insertion hole is formed across these hole portions, and a partition portion separating the two hole portions prevents difficulty in inserting a finger into each hole portion . A sensor unit as described in any one of claims 2 to 4, wherein a recess is formed in the edge portions of the pair of adjacent detection units facing each other across the boundary portion by recessing a portion of the edge portion, and when the detection units are attached, the attachment portion is located at a position surrounded by the recess. the boundary portion between the pair of adjacent detection units extends in the same direction as the longitudinal direction of the linear portion,
a plurality of the attachment portions are arranged along the boundary portion,
6. The sensor unit according to claim 1 , wherein each of the pair of adjacent detecting portions is attached to each of the attachment portions. An industrial robot equipped with a sensor unit according to any one of claims 1 to 6.