Coupling device

Abstract

According to the present invention, a coupling device that is to be suspended from a sling of a rotary-wing aircraft for coupling to a target comprises a connection part that connects to the sling, a coupling part that is below the connection part when the connection part has been connected to the sling and the coupling device is being suspended and that couples to the target, and a cylindrical guide. The cylindrical guide has a first end part and a second end part in an up-down direction in which the connection part and the coupling part are aligned. The first end part is closer to the connection part than the second end part. The second end part is positioned below the first end part. The guide includes a tapered inside surface that is wider than the first end part. The coupling device also comprises at least one fan that has a propeller that rotates around a rotational axis that extends in a direction that intersects the up-down direction.

Description

Coupling device

[0001] The present disclosure relates to a coupling device that is suspended from a sling of a rotary-wing aircraft to couple a target.

[0002] A coupling device used when suspending a load to be transported from a sling suspended from a rotary-wing aircraft has been developed. By coupling a target disposed on the ground and connected to the load to be transported to the coupling device, the rotary-wing aircraft can suspend and transport the object to be transported.

[0003] For example, the coupling device disclosed in Patent Document 1 includes a guide for aligning with a target and a plurality of fans. The rotation axes of the plurality of fans extend in the vertical direction in a posture where the coupling device is suspended without tilting. In the coupling device of Chinese Patent Application Publication No. 116353828, a plurality of fans can be driven to adjust the position of the guide with respect to the target.

[0004] Each of the plurality of fans of the coupling device of Chinese Patent Application Publication No. 116353828 generates a vertical thrust in a posture where the coupling device is suspended without tilting. Therefore, when moving the coupling device in a direction intersecting the vertical direction, the control or operation of the plurality of fans becomes relatively complicated.

[0005] This specification discloses a coupling device that is suspended from a sling of a rotary-wing aircraft to couple a target. The coupling device includes a connection portion for connecting the sling, a coupling portion that is located below the connection portion in a suspended state where the connection portion is connected to the sling and suspended, and is coupled to the target, and a cylindrical guide. The cylindrical guide has a first end portion and a second end portion in the vertical direction in which the connection portion and the coupling portion are aligned. The first end portion is closer to the connection portion than the second end portion. The second end portion is located below the first end portion. The guide includes an inner surface having a tapered shape with a width larger than the width of the first end portion. The coupling device further includes at least one fan having a propeller that rotates about a rotation axis extending in a direction intersecting the vertical direction.

[0006] According to the coupling device of this disclosure, the propeller in at least one fan rotates around a rotation axis that extends in a direction intersecting the vertical direction, making it easier to control or operate at least one fan when moving the coupling device in a direction intersecting the vertical direction, compared to a configuration in which the rotation axis is parallel to the vertical direction.

[0007] This is a schematic diagram showing an example of use of the coupling device according to the first embodiment. This is a schematic front view showing the general configuration of the coupling device according to the first embodiment. This is a schematic side view showing the general configuration of the coupling device according to the first embodiment. This is a schematic plan view showing the general configuration of the coupling device according to the first embodiment, with the connection and coupling parts omitted. This is a schematic diagram showing an example of a configuration in which the coupling device is coupled to a target, with the fan omitted. This is a perspective view showing a specific example of the coupling device according to the second embodiment, with the connection and coupling parts omitted. This is a plan view showing a specific example of the coupling device according to the second embodiment, with the connection and coupling parts omitted. This is a front view showing a specific example of the coupling device according to the second embodiment, with the connection and coupling parts omitted. This is a side view showing a specific example of the coupling device according to the second embodiment, with the connection and coupling parts omitted. This is a schematic plan view showing the general configuration of the coupling device according to the third embodiment, with the connection and coupling parts omitted. This is a schematic plan view showing the general configuration of the coupling device according to the fourth embodiment, with the connection and coupling parts omitted. This is a schematic side view showing the general configuration of the coupling device according to the fifth embodiment. This is a schematic front view showing the general configuration of the coupling device according to the sixth embodiment. This is a schematic diagram showing the coupling device and target according to the seventh embodiment. This is a schematic plan view of the target shown in Figure 14.

[0008] Referring to Figures 1 to 5, a coupling system 20 including a coupling device 40 according to a non-limiting first embodiment will be described below. As shown in Figure 1, the coupling system 20 is used to couple a hovering rotary-wing aircraft 10 with a cargo 13 placed on the ground when the cargo 13 is transported in a suspended state by the rotary-wing aircraft 10. The rotary-wing aircraft 10 includes a helicopter. The rotary-wing aircraft 10 is an unmanned aircraft, but may also be a manned aircraft. The rotary-wing aircraft 10 is not limited to a helicopter and may also include a drone.

[0009] As shown in Figure 1, the coupling system 20 comprises a target 30 and a coupling device 40. The target 30 is a coupling device that is coupled to the coupling device 40 and is placed on a mounting surface. The mounting surface includes, for example, the ground, the top surface of the transported object 13, or the top surface of an object such as a building. The target 30 is connected to the transported object 13 via a long connector 12. The long connector 12 includes, for example, a wire or rope. The coupling device 40 is connected to a sling 11 suspended from the rotary-wing aircraft 10. When the rotary-wing aircraft 10 descends from a hovering position above the target 30, the coupling device 40 also descends and couples with the target 30. After the coupling device 40 and the target 30 are coupled, the rotary-wing aircraft 10 ascends and transports the transported object 13 while suspended.

[0010] In order to connect the coupling device 40 to the target 30, it is necessary to align the coupling device 40 with the target 30 so that the coupling device 40 overlaps with the target 30 in the vertical direction. However, in situations where precise position adjustment of the rotary-wing aircraft 10 is difficult, or when the coupling device 40 is shaken by the wind, it becomes difficult to align the coupling device 40 with the target 30. The coupling device 40 according to this embodiment has a function to move itself in the direction in which the sling 11 is shaken when connected to the sling 11. Figure 2 is a schematic front view of the coupling device 40. Figure 3 is a schematic side view of the coupling device 40. Figure 4 is a schematic top view of the coupling device 40.

[0011] The coupling device 40 comprises a connecting portion 50, a coupling portion 60, a guide 70, and at least one fan 79. The at least one fan 79 comprises a first fan 80, a second fan 81, a third fan 82, and a fourth fan 83. The coupling device 40 further comprises a camera 78. The connecting portion 50 is the portion to which the sling 11 is connected. The coupling portion 60 is the portion to which the target 30 is coupled. The coupling portion 60 is located below the connecting portion 50 when the connecting portion 50 is connected to the sling 11 and suspended. Hereinafter, for the sake of explanation, the direction in which the connecting portion 50 and the coupling portion 60 are aligned will be described as the vertical direction D1. The vertical direction D1 is parallel to the vertical direction, i.e., the direction of gravity, when the sling 11 and the coupling device 40 are suspended without tilting. In this embodiment, the connecting portion 50 and the sling 11 are separate and are connected in a detachable manner. In an alternative embodiment, the connecting portion 50 and the sling 11 may be a single, integrated unit that cannot be disconnected.

[0012] As shown in Figures 2 and 3, the guide 70 is a cylindrical member positioned below the coupling portion 60. The central axis 71 of the guide 70 is parallel to the vertical direction D1 and passes through the center of the guide 70. The guide 70 has a first end 72 and a second end 73 in the vertical direction D1. Each of the first end 72 and the second end 73 opens in the vertical direction D1. The first end 72 is the upper end of the guide 70 and is closer to the coupling portion 60 than the second end 73. The second end 73 is the lower end of the guide 70 and is located below the first end 72. The guide 70 has a tapered inner surface 74, and the width of the second end 73 is greater than the width of the first end 72. The inner surface 74 of the guide 70 guides the coupling portion 32 of the target 30, which will be described later, to the coupling portion 60 when coupling the target 30 and the coupling device 40. In this embodiment, the inner surface 74 has the shape of a frustoconical side surface. The inner surface 74 may have any shape as long as it can guide the joint portion 32 of the target 30 to the joint portion 60 along the inner surface 74. For example, the inner surface 74 may have the shape of the side surface of a frustum of a polygon.

[0013] Figure 5 is a schematic diagram showing an example of a configuration for connecting the coupling device 40 to the target 30. As shown in Figure 5, the target 30 comprises a projection 31, a coupling portion 32, and legs 33 for placing the target 30 on a mounting surface. In this embodiment, there are four legs 33. The projection 31 has a cylindrical shape and extends elongated upward from the upper end of the legs 33. The coupling portion 32 is located at the top of the projection 31. The coupling portion 32 may be, for example, an integral member with the projection 31. The coupling portion 32 has a hemispherical shape with a diameter larger than the diameter of the projection 31. The coupling portion 32 has a hemispherical shape where the width is greatest at the lower end and decreases from the lower end to the upper end. When the coupling portion 32 has a hemispherical shape, the guide 70 can move smoothly when it comes into contact with the inner surface 74 of the guide 70. The connecting portion 32 may have any shape as long as it has a flange that protrudes from the outer surface of the projection 31 over its entire circumference in a direction perpendicular to the vertical direction D1.

[0014] When coupling the coupling device 40 with the target 30, the rotor-wing aircraft 10 suspending the coupling device 40 descends so that the projection 31 fits within the guide 70. In other words, when coupling the coupling device 40 with the target 30, the rotor-wing aircraft 10 suspending the coupling device 40 descends so that the projection 31 fits within the space 75 defined by the inner surface 74 of the guide 70. Once the guide 70 descends so that the projection 31 fits within the space 75 and the coupling portion 32 contacts the inner surface 74, the coupling portion 32 slides along the inner surface 74, guiding it to a position where it protrudes upward from the first end 72 of the guide 70, as shown in Figure 5.

[0015] In this embodiment, the connecting portion 50 includes a plate member having an engagement hole 51. The shape of the connecting portion 50 is not particularly limited as long as it has an engagement hole 51. The sling 11 is connected to the connecting portion 50 using the engagement hole 51. For example, a latching hook or a swivel may be used to engage the sling 11 with the engagement hole 51. In this embodiment, the coupling portion 60 includes a base member. The shape of the connecting portion 50 is not particularly limited. The connecting portion 50 and the coupling portion 60 are integrated by a fastener. The fastener includes, for example, a bolt or a rivet. In an alternative embodiment, the connecting portion 50 and a part of the coupling portion 60 may be an inseparable, integrated piece. The coupling portion 60 comprises a coupling portion body 60A, a fixing portion 61 for fixing the coupling portion 60 to the guide 70, an engagement member 64, and a biasing member 65. The coupling portion body 60A is integrated with the connecting portion 50. The coupling portion body 60A has a connecting hole 62 for connecting to the target 30. The connecting hole 62 is a bottomed hole with an open bottom and an inner diameter slightly larger than the outer diameter of the connecting portion 32 of the target 30. The inner diameter of the opening 62A of the connecting hole 62 is equal to or slightly larger than the inner diameter of the opening 74A at the upper end of the inner surface 74 of the guide 70. This makes it difficult for the connecting portion 32 to enter the connecting hole 62 when the connecting portion 32 moves along the inner surface 74 of the guide 70, as the connecting portion 32 catches on the peripheral edge of the opening 62A of the connecting portion body 60A. The connecting portion body 60A may have a tapered surface near the opening 62A of the connecting hole 62 that defines a part of the connecting hole 62 and has a lower end width greater than the upper end width.

[0016] The coupling body 60A has a lateral hole 63 that communicates with the connecting hole 62. The engaging member 64 is housed in the lateral hole 63 in a manner that prevents it from coming loose. In other words, the engaging member 64 is held in place so as not to fall out of the lateral hole 63. The biasing member 65 is positioned in a compressed state between the lid 66 that closes the lateral hole 63 and the engaging member 64. In this embodiment, the biasing member 65 is a coil spring. The biasing member 65 biases the engaging member 64 so that its tip protrudes into the connecting hole 62. When the coupling portion 32 of the target 30 is inserted into the connecting hole 62 of the coupling body 60A, and the coupling portion 60 descends further, the coupling portion 32 comes into contact with the engaging member 64 and presses against it. As a result, the engaging member 64 moves away from the coupling portion 32 against the biasing force of the biasing member 65. When the engaging member 64 moves away from the connecting portion 32, the connecting portion 32 can be positioned above the engaging member 64. When the connecting portion 32 moves above the engaging member 64, the biasing force of the biasing member 65 causes the tip of the engaging member 64 to protrude into the connecting hole 62 and return it to its initial position. When the engaging member 64 returns to its initial position, the connecting portion 32 becomes immobile from the connecting hole 62, and the coupling device 40 and the target 30 are coupled.

[0017] To release the coupling between the coupling device 40 and the target 30, the engaging member 64 is moved from its initial position to the release position. When the engaging member 64 is moved to the release position, it does not protrude from the lateral hole 63 into the coupling hole 62. The engaging member 64 is moved from the initial position to the release position by, for example, an electric actuator. The electric actuator includes an electric motor or a solenoid. If the electric actuator includes an electric motor, the electric motor may move the engaging member 64 via a reduction gear. After the electric actuator has moved the engaging member 64 from the initial position to the release position, the engaging member 64 is moved back to the initial position by a biasing member 65. Instead of an electric actuator, the engaging member 64 may be moved from the initial position to the release position by manually displacing an operating member that is interlocked with the engaging member 64. Any structure can be adopted as long as the engaging member 64, which is in the initial position, can be moved away from the coupling portion 32.

[0018] In an alternative embodiment, the coupling portion 60 and the target 30 may be detachably coupled by any known coupling structure. For example, as a known coupling structure, the configuration described in Chinese Patent Application Publication No. 111017217 may be adopted. Chinese Patent Application Publication No. 111017217 is incorporated in its entirety by reference.

[0019] The first to fourth fans 80-83 are selectively driven to generate thrust for positioning the coupling device 40. In this embodiment, the first to fourth fans 80-83 are positioned at the same location in the vertical direction D1. In other words, in this embodiment, the first to fourth fans 80-83 are positioned at the same height in the vertical direction D1. As shown in Figure 4, the first to fourth fans 80-83 are positioned to completely overlap the guide 70 when viewed from the vertical direction D1. That is, the first to fourth fans 80-83 do not protrude beyond the widest part of the guide 70 in the direction perpendicular to the vertical direction D1, so the coupling device 40 can be made more compact in the direction perpendicular to the vertical direction D1. In an alternative embodiment, the first to fourth fans 80-83 may be positioned to partially overlap the guide 70 when viewed from the vertical direction D1. In a further alternative embodiment, the first to fourth fans 80-83 may be located outside the guide 70 when viewed from the vertical direction D1.

[0020] The first to fourth fans 80 to 83 have a common structure. Each of the first to fourth fans 80 to 83 includes a propeller and an electric motor that rotates the propeller. The first fan 80 includes a propeller 80A and an electric motor 80B that rotates the propeller 80A. The propeller 80A rotates around a rotation axis 80a. The second fan 81 includes a propeller 81A and an electric motor 81B that rotates the propeller 81A. The propeller 81A rotates around a rotation axis 81a. The third fan 82 includes a propeller 82A and an electric motor 82B that rotates the propeller 82A. The propeller 82A rotates around a rotation axis 82a. The fourth fan 83 includes a propeller 83A and an electric motor 83B that rotates the propeller 83A. The propeller 83A rotates around the rotation axis 83a. Each of the rotation axes 80a to 83a extends in a direction intersecting the vertical direction D1. In other words, each of the rotation axes 80a to 83a extends non-parallel to the vertical direction D1. In this embodiment, each of the rotation axes 80a to 83a is parallel to each other and extends in a direction perpendicular to the vertical direction D1. Each of the first to fourth fans 80 to 83 preferably further includes a cover member that protects the propeller and the electric motor. The cover member includes, for example, a cylindrical member that surrounds the propeller around the rotation axes 80a to 83a. The cover member allows the airflow from the propeller to be concentrated in one direction, ensuring stable thrust. In the airflow direction of the first to fourth fans 80 to 83, for example, the propeller may be located downstream of the electric motor or upstream of the electric motor. The propeller may be located on the outer circumference of the electric motor. The propeller preferably includes multiple blades. Each of the rotation axes 80a to 83a may include the rotation axis of an electric motor. In Figure 4, the airflow directions of the first to fourth fans 80 to 83 are indicated by arrows. The indication of the airflow direction of the fans by arrows is also the case in other drawings.

[0021] In this embodiment, the first to fourth fans 80 to 83 are positioned to be rotationally symmetric with respect to the central axis 71 of the guide 70. This arrangement allows for smooth translational motion of the coupling device 40 in a direction intersecting the vertical direction D1, and rotational motion about a rotation axis parallel to the vertical direction D1. In this embodiment, the rotational motion about a rotation axis parallel to the vertical direction D1 is rotational motion about the central axis 71. In this embodiment, the translational motion of the coupling device 40 in a direction intersecting the vertical direction D1 is, more precisely, motion in the direction in which the sling 11 swings. For example, if the first fan 80 and the second fan 81 are driven to produce the same thrust, and the third fan 82 and the fourth fan 83 are stopped, the coupling device 40 can be translated to the right on the plane of Figure 4. For example, if the third fan 82 and the fourth fan 83 are driven to produce the same thrust, and the first fan 80 and the second fan 81 are stopped, the coupling device 40 can be translated to the left on the plane of Figure 4. For example, if two fans on diagonal lines with the central axis 71 in between are driven, the coupling device 40 can be rotated about the central axis 71. For example, if the first fan 80 and the third fan 82 are driven, the coupling device 40 can be rotated clockwise about the central axis 71 in Figure 4. For example, if the second fan 81 and the fourth fan 83 are driven, the coupling device 40 can be rotated counterclockwise about the central axis 71 in Figure 4.

[0022] In this embodiment, as shown in Figure 4, the first to fourth fans 80 to 83 blow air in a direction perpendicular to the vertical direction D1 and away from the central axis 71 of the guide 70. With this configuration, the coupling device 40 can be efficiently moved in a direction that intersects the vertical direction. The direction of airflow from the first to fourth fans 80 to 83 can also be defined as a direction away from a predetermined plane that includes the central axis 71. An example of a predetermined plane is a plane that includes the central axis 71 and is perpendicular to the rotation axes 80a to 83a.

[0023] In this embodiment, as shown in Figures 2 and 3, the first to fourth fans 80 to 83 are located below the connection portion 50 in the vertical direction D1. With this configuration, the length of the coupling device 40 can be shortened in the vertical direction D1, and it can be made smaller. The first to fourth fans 80 to 83 are located below the first end 72 of the guide 70 in the vertical direction D1. With this configuration, the length of the coupling device 40 can be shortened in the vertical direction D1, and it can be made smaller. In an alternative embodiment, each of the first to fourth fans 80 to 83 may be partially located below the first end 72 of the guide 70 in the vertical direction D1. In an alternative embodiment, at least one of the first to fourth fans 80 to 83 may be partially located below the first end 72 of the guide 70 in the vertical direction D1.

[0024] In this embodiment, as shown in Figures 2 and 3, the first to fourth fans 80 to 83 are positioned to overlap with the center of gravity 41 of the coupling device 40 in the vertical direction D1. This configuration allows the coupling device 40 to be moved more stably. In an alternative embodiment, the first to fourth fans 80 to 83 may be positioned not to overlap with the center of gravity 41 of the coupling device 40 in the vertical direction D1. This configuration allows for greater flexibility in the arrangement of the first to fourth fans 80 to 83.

[0025] Camera 78 photographs the space 75 within the guide 70 and the space facing the opening 76 of the second end 73 of the guide 70. The user can easily position the coupling device 40 relative to the target 30 so that the coupling portion 32 of the target 30 fits into the space 75 of the guide 70 by remotely operating the first to fourth fans 80-83 while viewing the image acquired by camera 78. In this embodiment, camera 78 has a field of view that includes the entire edge defining the opening 76 of the second end 73 of the guide 70. This configuration makes it even easier to position the coupling device 40 relative to the target 30. In an alternative embodiment, a controller may automatically position the coupling device 40 relative to the target 30 based on the image acquired by camera 78. The controller may be mounted on the coupling device 40. Alternatively, the controller may be carried by the user. In this case, the controller may remotely operate the first to fourth fans 80-83 via wireless communication. The controller may include memory and a processor that executes programs stored in the memory.

[0026] In this embodiment, as shown in Figure 2, the camera 78 is positioned outside the space 75 within the guide 70. The guide 70 has a transparent portion, and the camera 78 takes images through this transparent portion. With this configuration, the camera 78 does not get in the way when the inner surface 74 of the guide 70 guides the coupling portion 32 of the target 30. In an alternative embodiment, the guide 70 has a hole, and the camera 78 may take images through this hole. If the guide 70 has a hole for the camera 78 to take images, the coupling portion 32 can be prevented from getting caught in the hole by making the hole large enough so that the coupling portion 32 does not enter it.

[0027] In the coupling device 40, each of the first to fourth fans 80 to 83 has a propeller that rotates around a rotation axis 80a to 83a that extends in a direction intersecting the vertical direction D1. With the coupling device 40, the horizontal position of the coupling device 40 can be positioned appropriately relative to the target 30 with simpler control or operation of the first to fourth fans 80 to 83 compared to a configuration in which the rotation axes 80a to 83a are parallel to the vertical direction D1. In particular, when the coupling device 40 is suspended without tilting, the control or operation of the first to fourth fans 80 to 83 becomes even easier. Furthermore, in the coupling device 40, since the first to fourth fans 80 to 83 generate thrust in a direction intersecting the vertical direction D1, the energy required to align the coupling device 40 can be reduced. In particular, in this embodiment, the rotational axes 80a to 83a are perpendicular to the vertical direction D1, which greatly reduces the energy required for aligning the coupling device 40.

[0028] In a configuration where the rotation axes 80a to 83a are parallel to the vertical direction D1, if the first to fourth fans 80 to 83 are not positioned so as not to overlap with the guide 70 when viewed from the vertical direction D1, the air generated by the first to fourth fans 80 to 83 will hit the guide 70. In such a configuration, the positional operability of the coupling device 40 by the first to fourth fans 80 to 83 is hindered. On the other hand, with the coupling device 40 according to this embodiment, even if the first to fourth fans 80 to 83 are positioned so as to overlap with the guide 70 when viewed from the vertical direction D1, the air generated by the first to fourth fans 80 to 83 can be positioned so as not to hit the guide 70, thereby improving the degree of freedom in mounting the first to fourth fans 80 to 83.

[0029] The coupling device 140 according to the second embodiment will be described below with reference to Figures 6 to 9. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will be omitted. In Figures 6 to 9, the same components as in the first embodiment are denoted by the same reference numerals as in the first embodiment. Also, in Figures 6 to 9, the connection part 50, coupling part 60 and camera 78 are omitted from the illustration for the sake of simplicity. As shown in Figures 6 to 9, the coupling device 140 includes a fifth fan 184 and a sixth fan 185 in addition to the first to fourth fans 80 to 83. The fifth fan 184 includes a propeller and an electric motor that rotates the propeller. The propeller of the fifth fan 184 rotates around the rotation axis 184a. The sixth fan 185 includes a propeller and an electric motor that rotates the propeller. The propeller of the sixth fan 185 rotates around the rotation axis 185a. Each of the fifth fan 184 and the sixth fan 185 preferably further includes a cover member that protects the propeller and the electric motor. The propeller preferably includes a plurality of blades. Each of the rotation axes 184a and 185a may include the rotation axis of the electric motor.

[0030] The fifth fan 184 and the sixth fan 185 are positioned 180 degrees rotationally symmetric with respect to the central axis 71. The second direction D3, which is the direction in which the rotation axes 184a and 185a of the fifth fan 184 and the sixth fan 185 extend, is perpendicular to the first direction D2, which is the direction in which the rotation axes 80a to 83a of the first to fourth fans 80 to 83 extend. With this configuration, the coupling device 140 can be translated in both the first direction D2 and the second direction D3 without rotating the coupling device 140. Therefore, the positional maneuverability of the coupling device 140 is improved.

[0031] As shown in Figures 6 and 8, the propellers 80A to 82A of the first to third fans 80 to 82 are positioned so as not to overlap with the guide 70 when viewed from the first direction D2. Similarly, the propeller of the fourth fan 83 is also positioned so as not to overlap with the guide 70 when viewed from the first direction D2. With this configuration, the wind generated by the first to fourth fans 80 to 83 does not hit the guide 70, so thrust can be efficiently generated by the first to fourth fans 80 to 83. In an alternative embodiment, the propellers of the fifth fan 184 and the sixth fan 185 may be positioned so as not to overlap with the guide 70 when viewed from the second direction D3. With this configuration, the wind generated by the fifth fan 184 and the sixth fan 185 does not hit the guide 70, so thrust can be efficiently generated by the fifth fan 184 and the sixth fan 185.

[0032] The coupling device 140 further comprises a guide frame 77. The guide frame 77 comprises a lower member 77a, an upper member 77b, and a plurality of connecting portions 77c that connect the lower member 77a and the upper member 77b. The lower member 77a has a larger diameter than the upper member 77b. The lower portions of the lower member 77a and the connecting portions 77c have a size and shape that conforms to the outer shape of the guide 70. The upper member 77b is located above the first end portion 72. The upper member 77b has a mounting portion 77d for attaching the connecting portion 50 and the coupling portion 60. The mounting portion 77d is fixed, for example, to the fixing portion 61 of the coupling portion 60 according to the first embodiment. By providing the guide frame 77, the guide 70 can be made lighter while still having the necessary rigidity.

[0033] As shown in Figures 6 to 9, the coupling device 140 includes a mounting member 190. The mounting member 190 surrounds the guide 70 in a circumferential direction with respect to the central axis 71 at a position slightly below the first end 72. In this embodiment, the mounting member 190 is fixed to the connecting portion 77c of the guide frame 77. The mounting member 190 may be fixed to the connecting portion 77c of the guide frame 77 by welding or by fasteners. Fans 80-83, 184, and 185 are attached to the mounting member 190 via brackets 192. By using the mounting member 190, the fans 80-83, 184, and 185 can be stably mounted. If the mounting member 190 is attached to the guide frame 77 after the fans 80-83, 184, and 185 have been attached to the mounting member 190, it is not necessary to individually position the fans 80-83, 184, and 185 relative to the guide 70, and the coupling device 140 can be assembled more easily. As shown in Figure 7, the mounting member 190 is located inside the outer casing of the guide 70, i.e., inside the second end 73, when viewed from the vertical direction D1. Therefore, the coupling device 140 can be miniaturized in the direction perpendicular to the vertical direction D1. In an alternative embodiment, the fans 80-83, 184, and 185 may be directly attached to the mounting member 190. By directly attaching the fans 80-83, 184, and 185 to the mounting member 190, the number of parts can be reduced and the weight can be reduced.

[0034] The coupling device 140 further comprises a support plate 191 and a controller 193. As shown in Figures 6 and 7, the support plate 191 is mounted inside the mounting member 190. One or more controllers 193 and one or more batteries 194 are mounted on the support plate 191. The controller 193 is housed in a housing. The controller 193 includes a processor and memory, and the processor controls the operation of fans 80-83, 184, and 185 by executing a program stored in the memory. The controller 193 may also include a wireless communication device. The controller 193 may operate based on commands input to the controller 193 via wireless communication from a remote controller carried by the user. The camera 78 is electrically connected to the controller 193. The images acquired by the camera 78 are wirelessly transmitted to the remote controller by the wireless communication device of the controller 193.

[0035] The battery 194 supplies power to the controller 193 and fans 80-83, 184, and 185. The battery 194 also supplies power to the controller 193. The battery 194 is removable, and the operating time of the coupling device 140 can be extended by replacing the battery 194. The support plate 191 has a mounting portion to which the battery 194 is removablely attached.

[0036] The coupling device 240 according to the third embodiment will be described below with reference to Figure 10. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will not be described. In Figure 10, the same components as in the first embodiment are denoted by the same reference numerals as in the first embodiment. Figure 10 corresponds to Figure 4 of the first embodiment. The coupling device 240 is equipped with first to fourth fans 280 to 283 instead of first to fourth fans 80 to 83. The configuration of the first to fourth fans 280 to 283 is the same as the configuration of the first to fourth fans 80 to 83. The first to fourth fans 280 to 283 are positioned in a rotationally symmetric position with respect to the central axis 71 and partially overlap the guide 70 when viewed from the vertical direction D1. The rotation axis 280a of the first fan 280 and the rotation axis 282a of the third fan 282 are parallel, and the rotation axis 281a of the second fan 281 and the rotation axis 283a of the fourth fan 283 are parallel. The rotation axes 280a, 282a and the rotation axes 281a, 283a are orthogonal. In this embodiment, each of the first to fourth fans 280 to 283 blows air perpendicular to the vertical direction D1 and away from the central axis 71 of the guide 70. Even with this configuration, by selectively driving the fans 280 to 283, the coupling device 240 can be translated in both the direction of extension of the rotation axes 280a, 282a and the direction of extension of the rotation axes 281a, 283a. In an alternative embodiment, at least one of the first to fourth fans 280 to 283 may partially overlap the guide 70 when viewed from the vertical direction D1.

[0037] The coupling device 340 according to the fourth embodiment will be described below with reference to Figure 11. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will not be described. In Figure 11, the same reference numerals are used for components that are the same as in the first embodiment. Figure 10 corresponds to Figure 4 of the first embodiment. The coupling device 340 is equipped with first to fourth fans 380 to 383 instead of first to fourth fans 80 to 83. The configuration of the first fan 380 and the second fan 381 is the same as that of the first fan 80 and the second fan 81. The configuration of the third fan 382 and the fourth fan 383 is the same as that of the third fan 82 and the fourth fan 83, except that a variable pitch propeller is used. The first fan 380 and the second fan 381 are positioned opposite each other across the central axis 71 and partially overlap the guide 70 when viewed from the vertical direction D1. The third fan 382 and the fourth fan 383 are positioned so that the first to fourth fans 380-383 are aligned in a straight line. The third fan 382 and the fourth fan 383 are positioned opposite each other across the central axis 71 and do not overlap the guide 70 when viewed from the vertical direction D1. The first to fourth fans 380-383 are directly or indirectly attached to a long mounting member 390.

[0038] The rotation axis 380a of the first fan 380 and the rotation axis 381a of the second fan 381 are parallel, and the rotation axis 382a of the third fan 382 and the rotation axis 383a of the fourth fan 383 are parallel. The rotation axes 380a, 381a and the rotation axes 382a, 383a are perpendicular. In this embodiment, the first fan 380 and the second fan 381 blow air perpendicular to the vertical direction D1 and away from the central axis 71 of the guide 70.

[0039] In this embodiment, the third fan 382 and the fourth fan 383 are equipped with reversible propellers whose blade pitch can be changed to both positive and negative values. The third fan 382 and the fourth fan 383 can selectively blow air in both directions along the rotation axes 382a and 383a. By changing their blowing directions, the third fan 382 and the fourth fan 383 can be used for both translation and rotation of the coupling device 340. If the blowing directions of the third fan 382 and the fourth fan 383 are the same, thrust for translation of the coupling device 340 can be obtained. If the blowing directions of the third fan 382 and the fourth fan 383 are opposite, thrust for rotation of the coupling device 340 can be obtained. Both directions of rotation can also be set. With the coupling device 340, the same operation as the coupling device 40 can be performed using fewer fans compared to the coupling device 40.

[0040] In this embodiment, the third fan 382 is positioned further out than the first fan 380 and the second fan 381 in the direction in which they are aligned, that is, further from the central axis 71. In other words, the distance between the third fan 382 and the fourth fan 383 is greater than the distance between the first fan 380 and the second fan 381. Therefore, when the coupling device 340 is rotated, a moment can be efficiently generated.

[0041] The coupling device 440 according to the fifth embodiment will be described below with reference to Figure 12. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will not be described. In Figure 12, the same reference numerals are used for components identical to those in the first embodiment. The coupling device 440 differs from the first embodiment only in the orientation of the rotation axes 81a to 83a of the first to fourth fans 80 to 83. As shown in Figure 12, the extension direction of the rotation axes 81a to 83a intersects the vertical direction D1 at a non-right angle. With this configuration, it is easy to operate the first to fourth fans 80 to 83 to stop the shaking when the coupling device 440 is shaking. The configuration of the coupling device 440 is not limited to the first embodiment, but can also be applied to other embodiments.

[0042] The coupling device 540 according to the sixth embodiment will be described below with reference to Figure 13. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will not be described. In Figure 13, the same reference numerals are used for components identical to those in the first embodiment. The coupling device 540 differs from the first embodiment only in the positions of the first to fourth fans 80 to 83. As shown in Figure 13, the first to fourth fans 80 to 83 are located at least partially below the center 70a of the guide 70 in the vertical direction D1. With this arrangement, the distance in the vertical direction D1 between the center of gravity 541 of the coupling device 540 and the first to fourth fans 80 to 83 is relatively large. Therefore, when the coupling device 540 is shaking, it is easier to operate the first to fourth fans 80 to 83 to stop the shaking.

[0043] The coupling system 620 according to the seventh embodiment will be described below with reference to Figures 14 and 15. In the following description, only the differences from the first embodiment will be described, and the same aspects as the first embodiment will not be described. In Figure 14, the same reference numerals as in the first embodiment are used for components identical to those in the first embodiment. The coupling system 620 comprises a coupling device 640 and a target 630. As shown in Figure 14, the coupling device 640 is equipped with a rotation restricting mechanism 690 at the second end 73 of the guide 70. The rotation restricting mechanism 690 comprises four sets of pins 691, a biasing member 692, and a support member 693. The four sets of pins 691, the biasing member 692, and the support member 693 are arranged at equal intervals in the circumferential direction with respect to the central axis 71. The number of sets of pins 691, biasing member 692, and support member 693 is not particularly limited, and at least one set is sufficient. The support member 693 houses the upper portion of the pin 691 and supports the pin 691 in a state that prevents it from coming loose. The biasing member 692 is housed inside the support member 693 in a compressed state and biases the pin 691 downward. In this embodiment, the biasing member 692 includes a coil spring.

[0044] As shown in FIG. 14, the target 630 includes a base 635, legs 633, and a plurality of connecting portions 634. The legs 633 extend upward from the base 635 and support the protrusion 31. The connecting portions 634 are used to connect the target 630 and the object to be conveyed. The object to be conveyed may be, for example, a robot for maintaining a windmill for wind power generation. Such a robot is also referred to as a blade maintenance robot.

[0045] As shown in FIGS. 14 and 15, the base 635 has a plurality of engaging holes 636 in its upper surface portion. The engaging holes 636 are bottomed holes. As shown in FIG. 15, the plurality of engaging holes 636 are arranged on the same circle centered on the coupling portion 32 when viewed in the vertical direction D1. The radial positions of the plurality of engaging holes 636 correspond to the radial positions of the pins 691 when the coupling portion 32 and the coupling portion 60 are connected.

[0046] When the coupling portion 60 and the coupling portion 32 of the target 630 are coupled, if the positions of the pins 691 and the engaging holes 636 do not match, the pins 691 abut against and are pressed against the base 635 and are displaced upward against the biasing force of the biasing member 692. In this state, when the coupling device 640 and the target 630 rotate relative to each other until the positions of the pins 691 and the engaging holes 636 match, each of the pins 691 fits into the corresponding engaging hole 636 by the biasing force of the biasing member 692. Thereby, the relative rotation of the coupling portion 60 and the target 630 about the central axis 71, and thus the relative rotation of the coupling device 640 and the target 630, is restricted. In the present embodiment, since the number of the engaging holes 636 is larger than the number of the pins 691, the rotation angle until the positions of the pins 691 and the engaging holes 636 match can be reduced.

[0047] According to this configuration, when the coupling device 640 and the target 630 are coupled to carry the object to be carried in a suspended state, if the first to fourth fans 80 are controlled to rotate the coupling device 640 while the rotation is restricted by the rotation restricting mechanism 690, the rotational force of the coupling device 640 is transmitted to the target 630, and thus to the object to be carried. Therefore, it is easy to arrange the object to be carried in a desired orientation. In an alternative embodiment, relative rotation between the coupling device 640 and the target 630 is restricted by any known engagement structure. The configuration of the seventh embodiment is applicable not only to the first embodiment but also to other embodiments.

[0048] As described above, several embodiments have been explained. However, the above-described embodiments are for facilitating the understanding of the present teachings and do not limit the present invention. The present invention can be modified and improved without departing from its spirit, and equivalents thereof are included in the present invention. Also, within the range where at least a part of the above-described problems can be solved or at least a part of the effects can be achieved, any combination or any omission of each component described in the claims and the specification is possible.

[0049] For example, the number of fans provided in the coupling device can be any number of one or more according to the operability required for the coupling device. Also, the arrangement of at least one fan can be arbitrarily set according to the operability required for the coupling device.

[0050] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0051] In each embodiment, the camera 78 may be omitted. Omitting the camera 78 makes the coupling device lighter. The battery 194 may be fixed to the coupling device in a way that prevents it from being detached. By fixing the battery 194 in a way that prevents it from being detached, the mounting part of the battery 194 can be simplified, making the coupling device lighter. In the fan, the cover member may be omitted.

[0052] This disclosure can also be implemented in the following embodiments. The various embodiments described below are not essential to this disclosure and can be arbitrarily combined with any other embodiments.

[0053] According to a first embodiment, a coupling device is provided for coupling a target, which is suspended from a sling of a rotary-wing aircraft. The coupling device of the first embodiment comprises a connecting portion for connecting a sling, a coupling portion located below the connecting portion in a suspended state when the connecting portion is connected to the sling and coupled to a target, and a cylindrical guide. The cylindrical guide has a first end and a second end in the vertical direction where the connecting portion and the coupling portion are aligned. The first end is closer to the connecting portion than the second end. The second end is located below the first end. The guide includes a tapered inner surface that is wider than the width of the first end. The coupling device further comprises at least one fan having a propeller that rotates about a rotation axis extending in a direction intersecting the vertical direction.

[0054] According to the coupling device of the first embodiment, at least one fan has a propeller that rotates about a rotation axis that extends in a direction intersecting the vertical direction. Therefore, when positioning the horizontal position of the coupling device in the appropriate location relative to the target, it is easier to control or operate at least one fan compared to a configuration in which the rotation axis is parallel to the vertical direction. Furthermore, the energy required for aligning the coupling device can be reduced compared to a configuration in which the rotation axis is parallel to the vertical direction.

[0055] According to a second embodiment, in the first embodiment, at least one fan is positioned to at least partially overlap the guide when viewed from the vertical direction. According to a second embodiment, the coupling device can be made more compact in a direction perpendicular to the vertical direction.

[0056] According to the third embodiment, in the first or second embodiment, the propeller of at least one fan is positioned so as not to overlap with the guide when viewed from the direction in which the axis of rotation extends. According to the third embodiment, since the airflow generated by at least one fan does not hit the guide, thrust can be efficiently generated by at least one fan. Furthermore, in contrast to a configuration in which the axis of rotation is parallel to the vertical direction, even if at least one fan is positioned so as to at least partially overlap with the guide when viewed from the vertical direction, the positional maneuverability of the coupling device by at least one fan is not hindered. This improves the degree of freedom in mounting at least one fan.

[0057] According to the fourth embodiment, in any of the first to third embodiments, at least one fan includes first to fourth fans. The rotation axes of the first to fourth fans are perpendicular to the vertical direction and parallel to each other. The first to fourth fans are positioned so as to be rotationally symmetric with respect to a central axis that is parallel to the vertical direction and passes through the center of the guide. According to the fourth embodiment, the coupling device can smoothly perform translational motion in a direction perpendicular to the vertical direction and rotational motion about a rotation axis parallel to the vertical direction.

[0058] According to the fifth embodiment, in any of the first to fourth embodiments, at least one fan blows air in a direction that intersects the vertical direction and is away from the central axis passing through the center of the guide or away from a predetermined plane including the central axis. According to the fifth embodiment, the coupling device can be moved efficiently.

[0059] According to the sixth embodiment, in any of the first to fifth embodiments, at least one fan is located below the connection. According to the sixth embodiment, the coupling device can be made more compact in the vertical direction.

[0060] According to the seventh embodiment, in any of the first to sixth embodiments, at least one fan is located at least partially below the first end of the guide in the vertical direction. According to the seventh embodiment, the coupling device can be miniaturized in the vertical direction.

[0061] According to the eighth aspect, in any of the first to seventh aspects, at least one fan is located at least partially below the center of the guide in the vertical direction. According to the eighth aspect, the vertical distance between the center of gravity of the coupling device and at least one fan is relatively large. Therefore, if the coupling device is shaking, it is easier to operate at least one fan to stop the shaking.

[0062] According to the ninth aspect, in any of the first to seventh aspects, at least one fan is positioned in a vertical direction that overlaps with the center of gravity of the coupling device. According to the ninth aspect, the coupling device can be moved more stably.

[0063] According to the tenth embodiment, in the fourth embodiment, or in any of the fifth to ninth embodiments including the fourth embodiment, at least one fan further includes fifth and sixth fans arranged parallel to the vertical direction and rotationally symmetric with respect to a central axis passing through the center of the guide. The second direction in which the rotation axes of the fifth and sixth fans extend is perpendicular to the vertical direction and perpendicular to the first direction in which the rotation axes of the first to fourth fans extend. According to the tenth embodiment, the coupling device can be translated in both the first and second directions. Therefore, the positional maneuverability of the coupling device is improved.

[0064] According to the eleventh embodiment, in the fourth embodiment, the fifth to ninth embodiments including the fourth embodiment, and the tenth embodiment, the coupling device includes an annular mounting member for directly or indirectly attaching the first to fourth fans. The mounting member is positioned to surround the guide in a circumferential direction with respect to the central axis of the guide in the vertical direction, and is located inside the outer casing of the guide when viewed from the vertical direction. According to the eleventh embodiment, the first to fourth fans can be stably attached. Furthermore, the coupling device can be assembled more easily if the mounting member is attached after the first to fourth fans have been attached to it. When the eleventh embodiment is combined with the tenth embodiment, the fifth and sixth fans may also be attached to the mounting member.

[0065] According to the twelfth embodiment, in any of the first to eleventh embodiments, the coupling device includes a removable battery that supplies power to at least one fan. According to the twelfth embodiment, the operating time of the coupling device can be extended by replacing the battery.

[0066] According to the 13th embodiment, in any of the first to 12 embodiments, the coupling device includes a camera that photographs a space defined by the inner surface of the guide and a space facing the opening at the second end of the guide. According to the 13th embodiment, the coupling device can be easily positioned relative to the target by operating at least one fan while viewing the image acquired by the camera, such that the coupling portion of the target, i.e., the portion that connects with the coupling portion of the coupling device, fits inside the space of the guide.

[0067] According to the fourteenth embodiment, in the thirteenth embodiment, the camera has a field of view that includes the entire edge defining the opening at the second end of the guide. According to the fourteenth embodiment, the coupling device can be positioned more easily relative to the target.

[0068] According to the fifteenth embodiment, in the thirteenth or fourteenth embodiment, the guide has a hole or a transparent portion. The camera is positioned outside the space of the guide and takes pictures through the hole or transparent portion. According to the fifteenth embodiment, the camera does not get in the way when guiding the joint of the target along the inner surface of the guide.

[0069] According to the sixteenth aspect, in any of the first to fifteenth aspects, the coupling device includes a rotation restricting mechanism that, when the coupling portion is coupled to the target, contacts the target and restricts the relative rotation between the coupling portion and the target about an axis parallel to the vertical direction. According to the sixteenth aspect, even if the coupling portion of the coupling portion and the target has a coupling structure that allows relative rotation, the relative rotation between the coupling device and the target is restricted. Therefore, when the coupling device and the target are coupled and the object to be transported is suspended, controlling at least one fan to rotate the coupling device transmits the rotational force of the coupling device to the target, and consequently to the object to be transported. Thus, it is easier to position the object to be transported in the desired orientation.

[0070] 10...Helicopter, 11...Sling, 12...Long connector, 13...Plane to be carried, 20...Coupling system, 30...Target, 31...Protrusion, 32...Coupling part, 33...Leg part, 34...Connecting part, 40...Coupling device, 41...Center of gravity of coupling device, 50...Connecting part, 51...Engagement hole, 60...Coupling part, 60A...Coupling part body, 61...Fixing part, 62...Connecting hole, 62A...Opening, 63...Side hole, 64...Engaging member, 65...Biasing member, 66...Lid, 70...Guide, 71...Central axis, 72 ...First end, 73...Second end, 74...Inner surface, 74A...Opening, 75...Space, 76...Opening, 77...Guide frame, 77a...Lower member, 77b...Upper member, 77c...Connecting part, 77d...Mounting part, 78...Camera, 80...First fan, 81...Second fan, 82...Third fan, 83...Fourth fan, 80A, 81A, 82A, 83A...Propeller, 80B, 81B, 82B, 83B...Electric motor, 80a, 81a, 82a, 83a...Rotation axis, 140...Coupling device, 18 4...Fifth fan, 185...Sixth fan, 184a, 185b...Rotation axis, 190...Mounting member, 191...Support plate, 192...Bracket, 193...Controller, 194...Battery, 240...Coupling device, 280...First fan, 281...Second fan, 282...Third fan, 283...Fourth fan, 280a, 281a, 282a, 283a...Rotation axis, 340...Coupling device, 380...First fan, 381...Second fan, 382...Third fan, 383... .Fourth fan, 380a, 381a, 382a, 383a...Rotation axis, 390...Mounting member, 440...Coupling device, 540...Coupling device, 541...Center of gravity of coupling device, 570a...Center of guide, 620...Coupling system, 630...Target, 633...Legs, 634...Connecting part, 635...Base, 636...Engagement hole, 640...Coupling device, 690...Rotation restricting mechanism, 691...Pin, 692...Biasing member, 693...Support member, D1...Vertical direction, D2...First direction, D3...Second direction

Claims

1. A coupling device for coupling a target, suspended from a sling of a rotary-wing aircraft, comprising: a connecting portion for connecting the sling; a coupling portion located below the connecting portion in a suspended state when the connecting portion is connected to the sling and coupled to the target; a cylindrical guide having a first end and a second end in the vertical direction where the connecting portion and the coupling portion are aligned, wherein the first end is closer to the connecting portion than the second end, the second end is located below the first end, and the guide includes a tapered inner surface that is wider than the width of the first end; and at least one fan having a propeller that rotates about a rotation axis extending in a direction intersecting the vertical direction.

2. The coupling device according to claim 1, wherein the at least one fan is positioned to at least partially overlap the guide when viewed from the vertical direction.

3. A coupling device according to claim 1 or claim 2, wherein the propeller of at least one fan is positioned so as to not overlap with the guide when viewed from the direction in which the axis of rotation extends.

4. A coupling device according to any one of claims 1 to 3, wherein the at least one fan includes first to fourth fans, the rotation axes of the first to fourth fans are perpendicular to the vertical direction and parallel to each other, and the first to fourth fans are positioned to be rotationally symmetric with respect to a central axis that is parallel to the vertical direction and passes through the center of the guide.

5. A coupling device according to any one of claims 1 to 4, wherein at least one fan blows air in a direction that intersects the vertical direction and is away from a central axis passing through the center of the guide or away from a predetermined plane including the central axis.

6. A coupling device according to any one of claims 1 to 5, wherein at least one fan is located below the connection portion.

7. A coupling device according to any one of claims 1 to 6, wherein the at least one fan is located at least partially below the first end of the guide in the vertical direction.

8. A coupling device according to any one of claims 1 to 7, wherein the at least one fan is located at least partially below the center of the guide in the vertical direction.

9. A coupling device according to any one of claims 1 to 7, wherein the at least one fan is located in a position that overlaps with the center of gravity of the coupling device in the vertical direction.

10. A coupling device according to claim 4 and any one of claims 5 to 9, which includes claim 4 as a dependent, wherein the at least one fan further includes fifth and sixth fans arranged parallel to the vertical direction and rotationally symmetric with respect to a central axis passing through the center of the guide, the second direction in which the rotation axes of the fifth and sixth fans extend is perpendicular to the vertical direction and perpendicular to the first direction in which the rotation axes of the first to fourth fans extend.

11. A coupling device according to any one of claims 4, claims 5 to 9, and 10, which include claim 4 as a dependent, comprising an annular mounting member for directly or indirectly attaching the first to fourth fans, wherein the mounting member is arranged to surround the guide in a circumferential direction with respect to the central axis of the guide in the vertical direction, and is located inside the outer casing of the guide when viewed from the vertical direction.

12. A coupling device according to any one of claims 1 to 11, comprising a removable battery for supplying power to at least one fan.

13. A coupling device according to any one of claims 1 to 12, comprising a camera for photographing the space defined by the inner surface of the guide and the space facing the opening of the second end of the guide.

14. A coupling device according to claim 13, wherein the camera has a field of view that includes the entire edge of the second end of the guide that defines the opening.

15. A coupling device according to claim 13 or claim 14, wherein the guide has a hole or a transparent portion, and the camera is positioned outside the space of the guide and takes images through the hole or the transparent portion.

16. A coupling device according to any one of claims 1 to 15, comprising a rotation restricting mechanism that, when the coupling portion is coupled to the target, contacts the target and restricts the relative rotation between the coupling portion and the target about an axis parallel to the vertical direction.

Images