Power transmission device and joint device

Abstract

A power transmission device (TM1) is provided with an interrupter mechanism (20) and a transmission (T). The transmission (T) includes a second planetary mechanism (P2) including a sun gear (SG2), a carrier (PC2), and a ring gear (RG2), and changes the rotational power between the first shaft (181) and the second shaft (182). The carrier (PC2) and the ring gear (RG2) are disposed further outward than the second shaft (182) in the radial direction, and are disposed such that at least a portion thereof overlaps the second shaft (182) when viewed in the radial direction.

Description

TECHNICAL FIELD

[0001] The present application relates to a power transmission device and a joint device. BACKGROUND

[0002] In the past, a power transmission device has been known that includes a transmission that changes the power of a power source, and a cutout mechanism that switches the cutout and connection of the power. For example, in Patent Literature 1, a joint device that uses such a power transmission device for an electric artificial leg or the like is described. In the joint device described in Patent Literature 1, the transmission has two power transmission paths that differ in transmission ratio, and switches the power transmission path at the time of standing and at the time of lifting the leg.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: International Publication No. 2021 / 251500 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] A power transmission device is used in various devices, and it is therefore desirable to be small.

[0008] The present application provides a power transmission device and a joint device that can be made small.

[0009] SOLUTION TO THE PROBLEM

[0010] The present application is a power transmission device that includes a cutout mechanism and a transmission, in which

[0011] The cutout mechanism has:

[0012] a fitting member that is disposed between a first rotating body and a second rotating body; and

[0013] an operation portion that operates the fitting member to a fitting state in which the first rotating body and the second rotating body can rotate integrally, and a non-fitting state in which the first rotating body and the second rotating body can rotate relatively,

[0014] The operation portion has:

[0015] an action member that moves the fitting member; and

[0016] an operation member that is provided so as to be able to operate the fitting member via the action member, or so as to be able to operate the fitting member without passing through the action member,

[0017] the first rotating body and the second rotating body are configured to have their rotational axes coincide with each other and at least a part of each of them to overlap with each other when viewed in the radial direction with respect to the rotational axes,

[0018] the operation member has:

[0019] a moving-back-and-forth member configured to be movable back and forth along the radial direction; and

[0020] an extension portion configured to extend along the rotational axis and to be movable back and forth along the rotational axis,

[0021] the transmission has a transmission portion having: a first rotating element composed of the first rotating body or a rotating body that rotates integrally with the first rotating body; a second rotating element configured to be rotatable in transmission with the first rotating element; and a third rotating element configured to be rotatable in transmission with the second rotating element,

[0022] the second rotating element and the third rotating element are configured to be positioned outward of the second rotating body in the radial direction and to at least partially overlap with the second rotating body when viewed in the radial direction.

[0023] Further, the present application is a power transmission device that has a discontinuous mechanism and a transmission, wherein

[0024] the discontinuous mechanism has:

[0025] an engaging member configured to be positioned between the first rotating body and the second rotating body; and

[0026] an operation portion that operates the engaging member to an engaged state in which the first rotating body and the second rotating body are integrally rotatable and a non-engaged state in which the first rotating body and the second rotating body are relatively rotatable,

[0027] the operation portion has:

[0028] a moving member that moves the engaging member; and

[0029] an operation member configured to be able to operate the engaging member via the moving member or to be able to operate the engaging member without the moving member,

[0030] the first rotating body and the second rotating body are configured to have their rotational axes coincide with each other and at least a part of each of them to overlap with each other when viewed in the radial direction with respect to the rotational axes,

[0031] the operation member has:

[0032] a moving-back-and-forth member configured to be movable back and forth along the radial direction; and

[0033] an extension portion provided so as to extend along the rotation axis and capable of advancing and retreating along the rotation axis,

[0034] The transmission has a planetary gear portion,

[0035] The planetary gear portion has a first rotary element, a third rotary element, a fourth rotary element disposed between the first rotary element and the third rotary element in a manner capable of power transmission between the first rotary element and the third rotary element, and a second rotary element that supports the fourth rotary element so as to be capable of rotation and revolution, and is configured to satisfy a collinear relationship in which rotational speeds of three rotary elements constituted by the first rotary element, the third rotary element, and the second rotary element are arranged on a single straight line in a nomograph.

[0036] The rotation axis of the third rotary element of the planetary gear portion coincides with the rotation axes of the first rotary body and the second rotary body.

[0037] Further, the present application is a joint device including:

[0038] a first member;

[0039] a second member;

[0040] a connecting portion that connects the first member and the second member in a manner capable of changing an included angle between the first member and the second member; and

[0041] an expansion / contraction device that is capable of expanding and contracting the included angle between the first member and the second member, wherein

[0042] the expansion / contraction device includes the above-described power transmission device.

[0043] Further, the present application is a joint device including:

[0044] a first member;

[0045] a second member;

[0046] a connecting portion that connects the first member and the second member in a manner capable of changing an included angle between the first member and the second member; and

[0047] an expansion / contraction device that is capable of expanding and contracting the included angle between the first member and the second member, wherein

[0048] the expansion / contraction device has a power source and a power transmission device that transmits power of the power source,

[0049] the power transmission device has:

[0050] a first power transmission path that transmits the power at a first transmission ratio; and

[0051] a second power transmission path that transmits the power at a second transmission ratio different from the first transmission ratio,

[0052] The expansion / contraction device has:

[0053] a first interrupting mechanism that switches between interruption and connection of the power on the first power transmission path; and

[0054] a second interrupting mechanism that switches between interruption and connection of the power on the second power transmission path,

[0055] The first power transmission path includes a planetary gear unit,

[0056] The second power transmission path includes the planetary gear unit and another planetary gear unit different from the planetary gear unit.

[0057] Inventive Effects

[0058] According to the present application, a power transmission device and a joint device that can be downsized can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1 is a cross-sectional view of a power transmission device TM1 of a first embodiment of the present application.

[0060] Figure 2 is a cross-sectional view along the X-X line of Figure 1

[0061] Figure 3 is a cross-sectional view along the Y-Y line of Figure 1

[0062] Figure 4 is a perspective view of the retainer 282.

[0063] Figure 5 is a cross-sectional view showing that the interrupting portion 212 of the first interrupting mechanism 210 is in the disengaged state.

[0064] Figure 6 is a cross-sectional view showing that the interrupting portion 212 of the first interrupting mechanism 210 is in the engaged state.

[0065] Figure 7 is a diagram showing the operation of the power transmission device TM1, in which (A) is a cross-sectional view of the power transmission device TM1 showing the neutral state, (B) is a cross-sectional view of the power transmission device TM1 showing the high-speed rotation state, and (C) is a cross-sectional view of the power transmission device TM1 showing the high-torque state. ​​

[0066] Figure 8 This is a cross-sectional view showing the power transmission device TM2 according to the second embodiment of the present invention.

[0067] Figure 9 This is a cross-sectional view showing the power transmission device TM3 according to the third embodiment of the present invention.

[0068] Figure 10 This is a cross-sectional view showing the power transmission device TM4 according to the fourth embodiment of the present invention.

[0069] Figure 11 This is a cross-sectional view of a power transmission device TM4, a modified example of the fourth embodiment of the present invention.

[0070] Figure 12 The figure shows a fifth embodiment of the present invention, which is a perspective view of an electric prosthetic leg 1 assembled with a power transmission device TM1.

[0071] Figure 13 yes Figure 12 Side view of the electric prosthetic leg 1.

[0072] Figure 14 It shows Figure 12 A diagram of the internal structure of the electric prosthetic leg 1.

[0073] Figure 15 The diagram shows the user's and the electric prosthetic leg 1's movements when going up a step (the up-step movement).

[0074] Figure 16 It is a diagram showing the movements of the user and the electric prosthetic leg 1 when walking on flat ground (walking on flat ground movement).

[0075] Figure 17 This is a schematic diagram of the sixth embodiment of the present invention, which shows the internal structure of the electric prosthetic leg 1 assembled with the power transmission device TM1.

[0076] Figure 18 This is a diagram illustrating the seventh embodiment of the present invention, which shows the structure of a moving body M1 assembled with a power transmission device TM1. Detailed Implementation

[0077] Hereinafter, the power transmission devices of various embodiments of the present invention will be described with reference to the accompanying drawings.

[0078] (First Implementation)

[0079] like Figures 1 to 3As shown, the power transmission device TM1 includes: a first shaft 181 and a second shaft 182 having the same axis of rotation (hereinafter referred to as the axis of rotation L1), an intermittent mechanism 20 and a transmission T disposed on the power transmission path of the first shaft 181 and the second shaft 182, and a housing 180 housing these components. The housing 180 has a generally cylindrical shape, and supports the first shaft 181 for rotation via bearing 183, and supports the second shaft 182 for rotation via bearing 184. The end portion of the first shaft 181 extends from one end of the housing 180 in the direction of the axis of rotation ( Figure 1 The lower side of the housing 180 is exposed, and the end of the second shaft 182 extends from the other end of the housing 180 in the direction of the rotation axis. Figure 1 The upper side is exposed. Furthermore, in the first to sixth embodiments, the power transmission devices TM1 to TM4 are illustrated in a configuration where the direction of the rotation axis is vertical. Hereinafter, in the description of the power transmission devices TM1 to TM4 in the first to sixth embodiments, the direction of the rotation axis will also be referred to as the vertical direction.

[0080] The transmission T comprises a first power transmission path that transmits power from a power source (not shown) input from the first shaft 181 to the second shaft 182 at a first gear ratio, and a second power transmission path that transmits power to the second shaft 182 at a second gear ratio different from the first gear ratio. Detailed description follows: the transmission T includes a first planetary mechanism P1 and a second planetary mechanism P2. The first power transmission path includes the first planetary mechanism P1, and the second power transmission path includes both the first planetary mechanism P1 and the second planetary mechanism P2.

[0081] The intermittent mechanism 20 includes a first intermittent mechanism 210 and a second intermittent mechanism 220. The first intermittent mechanism 210 and the second intermittent mechanism 220 switch the disconnection and connection of power on the first power transmission path, and switch the disconnection and connection of power on the second power transmission path, as detailed later.

[0082] The first planetary mechanism P1 and the second planetary mechanism P2 each have sun gears SG1 and SG2, ring gears RG1 and RG2, multiple planetary gears PG1 and PG2 meshing with the sun gears SG1 and SG2 and the ring gears RG1 and RG2, and planet carriers PC1 and PC2 supporting the planetary gears PG1 and PG2 so that they can rotate on their own axis and revolve around the sun. The three rotating elements consisting of the sun gears SG1 and SG2, the ring gears RG1 and RG2, and the planet carriers PC1 and PC2 satisfy a collinear relationship in which their rotational speeds are always arranged on a single straight line in the velocity nomogram (also called a nomogram).

[0083] The sun gears SG1, SG2 and the planet carriers PC1, PC2 of the first planetary mechanism P1 and the second planetary mechanism P2 have the same rotational axis L1 as the first shaft 181 and the second shaft 182. The first planetary mechanism P1 and the second planetary mechanism P2 are arranged side by side in the rotational axis direction (up-down direction). The second planetary mechanism P2 is arranged at a position further outward than the second shaft 182, and is arranged so as to at least partially coincide with the second shaft 182 when viewed in the radial direction. In the present embodiment, the first planetary mechanism P1 is arranged at a position further downward than the second planetary mechanism P2, and the first planetary mechanism P1 is also arranged at a position further outward than the second shaft 182, and is arranged so as to at least partially coincide with the second shaft 182 when viewed in the radial direction.

[0084] The sun gear SG1 of the first planetary mechanism P1 is formed integrally with the first shaft 181. Alternatively, the sun gear SG1 of the first planetary mechanism P1 can be formed separately from the first shaft 181 and connected to the first shaft 181 in a manner that allows integral rotation. Thus, rotational power of the first shaft 181 is input to the first planetary mechanism P1. The sun gear SG1 of the first planetary mechanism P1 is supported with respect to the second shaft 182 in a rotatable manner via a bearing 185 arranged on the inner side.

[0085] The ring gear RG1 of the first planetary mechanism P1 is formed integrally with the housing 180. That is, the ring gear RG1 is not rotatable. Alternatively, the ring gear RG1 of the first planetary mechanism P1 can be formed separately from the housing 180 and mechanically connected to the housing 180 in a manner that does not allow rotation.

[0086] Thus, the planet carrier PC1 of the first planetary mechanism P1 reduces the rotation input from the sun gear SG1 and outputs it.

[0087] The planet carrier PC1 of the first planetary mechanism P1 is formed integrally with the sun gear SG2 of the second planetary mechanism P2. In the present embodiment, the sun gear SG2 is formed on the outer peripheral portion of the cylindrical portion PC1a formed integrally with the planet carrier PC1. Thus, it is possible to transmit rotational power reduced by the first planetary mechanism P1 to the second planetary mechanism P2.

[0088] The sun gear SG2 (cylindrical portion PC1a) of the second planetary mechanism P2 is connected to the second shaft 182 via the first interrupt mechanism 210. That is, in the present embodiment, the first interrupt mechanism 210 is provided between the cylindrical portion PC1a formed integrally with the planet carrier PC1 and the second shaft 182 located on the inner peripheral portion of the cylindrical portion PC1a. Thus, a first power transmission path including the first planetary mechanism P1 is formed.

[0089] The ring gear RG2 of the second planetary mechanism P2 is formed integrally with the housing 180. That is, the ring gear RG2 is not rotatable. In addition, the ring gear RG2 of the second planetary mechanism P2 is not necessarily formed integrally with the housing 180, but can be separate from the housing 180 and mechanically connected to the housing 180 in a manner that is not rotatable.

[0090] Thus, the carrier PC2 of the second planetary mechanism P2 reduces the rotation input from the sun gear SG2 and outputs it.

[0091] The carrier PC2 of the second planetary mechanism P2 is connected to the second shaft 182 via the second interrupt mechanism 220. In the present embodiment, the second interrupt mechanism 220 is provided between a cylindrical portion PC2a formed integrally with the carrier PC2 and the second shaft 182 located at the inner circumferential portion of the cylindrical portion PC2a. In addition, the cylindrical portion PC2a is not necessarily formed integrally with the carrier PC2, but can be separate from the carrier PC2 and mechanically connected to the carrier PC2 in a manner that is integrally rotatable. In addition, although not illustrated, a bearing that allows relative rotation can be provided between the rotating element of the first planetary mechanism P1 and the rotating element of the second planetary mechanism P2, between the housing 180 and the rotating element of the first planetary mechanism P1 or the second planetary mechanism P2.

[0092] In the transmission T thus configured, a first power transmission path that transmits the power of the power source input from the first shaft 181 to the second shaft 182 via the first planetary mechanism P1 and the first interrupt mechanism 210 is formed, and a second power transmission path that transmits the power via the first planetary mechanism P1, the second planetary mechanism P2, and the second interrupt mechanism 220 to the second shaft 182 is formed.

[0093] The first interrupt mechanism 210 has an interrupt portion 212 provided between the cylindrical portion PC1a and the second shaft 182. The second interrupt mechanism 220 has an interrupt portion 222 provided between the cylindrical portion PC2a and the second shaft 182. Next, the details of the interrupt portions 212, 222 will be described with reference to Figures 1 to 6 The details of the interrupt portions 212, 222 will be described.

[0094] The discontinuity sections 212 and 222 have a common structure, and are configured to switch between a cut-off state that cuts off the power transmission path and a connected state that connects the power transmission path. In this embodiment, each discontinuity section 212 and 222 is configured using a bidirectional clutch 280 with a forced-free function. The bidirectional clutch 280 includes: a plurality of (three in this embodiment) rollers 281 disposed between the outer peripheral surface of the second shaft 182 and the inner peripheral surface of the cylindrical portions PC1a and PC2a; a retainer 282 that holds the plurality of rollers 281 at a predetermined interval; an operating mechanism 240; a plurality of (three in this embodiment) pins 283 that radially penetrate the second shaft 182 and are operated by the operating mechanism 240 to a forced-free position and a forced-free release position; and a plurality of (three in this embodiment) guides 284 disposed on the retainer 282, which limit the relative rotational position of the retainer 282 relative to the second shaft 182 when the pins 283 are in the forced-free position. Roller 281 can be either a ball bearing or a wedge.

[0095] like Figure 2 As shown, the radial distance A between the outer peripheral surface of the second shaft 182 and the inner peripheral surface of the cylindrical portions PC1a and PC2a is smaller than the diameter B of the roller 281. In addition, flat portions 182a are formed at predetermined intervals along the circumferential direction on the outer peripheral portion of the second shaft 182, and the distance A is larger than the diameter B on the circumferential central side of the flat portions 182a.

[0096] That is, with the roller 281 held at the circumferential center of the flat portion 182a, the roller 281 does not engage with the outer circumferential surface of the second shaft 182 and the inner circumferential surface of the cylindrical portions PC1a and PC2a (non-engaged state), allowing relative rotation between the second shaft 182 and the cylindrical portions PC1a and PC2a (forced free state, see reference). Figure 5 ).

[0097] On the other hand, with the roller 281 allowed to move circumferentially relative to the second shaft 182, the roller 281 engages with the outer peripheral surface of the second shaft 182 and the inner peripheral surfaces of the cylindrical parts PC1a and PC2a (engaged state), and the second shaft 182 is connected to the cylindrical parts PC1a and PC2a in a manner that allows them to rotate integrally in both directions (forced free release state, see reference). Figure 6 ).

[0098] like Figure 4 As shown, the retainer 282 is an annular ring that can rotate relative to the second shaft 182 and the cylindrical portions PC1a and PC2a, and has a plurality of roller retaining portions 282a for retaining rollers 281 and a plurality of guide retaining portions 282b for retaining guides 284.

[0099] Furthermore, a plurality of rubber balls 282c are embedded at predetermined intervals along the circumferential direction on the outer peripheral surface of the retainer 282. These rubber balls 282c generate appropriate friction between the cylindrical portions PC1a and PC2a and the retainer 282, thereby preventing accidental free rotation in the forced free release state. Additionally, the component that generates friction between the cylindrical portions PC1a and PC2a and the retainer 282 is not limited to rubber balls 282c; it can also be an O-ring.

[0100] like Figure 5 As shown, pin 283 has a conical protrusion 283a at its radially outer end, and guide 284 has a conical recess 284a at its radially inner end face that engages (locks) with the protrusion 283a. When the protrusion 283a of pin 283 engages with the recess 284a of guide 284, the relative rotational position of retainer 282 relative to the second shaft 182 is positioned at a predetermined position that becomes a forced free state through the guiding action of pin 283 and guide 284.

[0101] return Figure 1 The operating mechanism 240 includes an operating lever 241 configured to perform intermittent operation on the intermittent sections 212 and 222, and a servo motor 242 for linearly moving the operating lever 241. The second shaft 182 is a hollow shaft having an internal space S extending along the direction of the rotation axis (also known as the up-down direction), and the operating lever 241 is disposed in this internal space S.

[0102] More specifically, also refer to Figure 7 The outer periphery of the operating lever 241 has small-diameter portions 241b1, 241b2 and large-diameter portions 241c1~241c3, which will be described later, and abuts against the inner diameter end (inner end) of the pin 283. Depending on the position of the operating lever 241, the small-diameter portions 241b1, 241b2 and large-diameter portions 241c1~241c3 cause the pin 283 to move forward and backward radially in the second shaft 182, or enable it to move forward and backward, thereby switching the state of the discontinuous portions 212, 222.

[0103] More specifically, such as Figure 7 As shown, on the outer periphery of the operating lever 241, a first large-diameter portion 241c1, a first small-diameter portion 241b1, a second large-diameter portion 241c2, a second small-diameter portion 241b2, and a third large-diameter portion 241c3 are formed sequentially from below at predetermined lengths and intervals. The operating lever 241 is configured to simultaneously control two discontinuous portions 212 and 222, but it can also be configured individually for each discontinuous portion 212 and 222.

[0104] like Figure 7 As shown, the discontinuous sections 212 and 222 are switched to a forced free state (hereinafter, appropriately referred to as the disconnected state) and a forced free release state (hereinafter, appropriately referred to as the engaged state) by the operating mechanism 240.

[0105] When the operation lever 241 of the operation mechanism 240 is in the lower position shown in (A) of FIG. 10, the second large-diameter portion 241c2 pushes the pin 283 of the dog portion 212 outward in the radial direction, and at the same time the third large-diameter portion 241c3 pushes the pin 283 of the dog portion 222 outward in the radial direction, thereby setting the dog portion 222 and the dog portion 212 to the disengaged state. That is, the first power transmission path and the second power transmission path become the disconnected state. Thereby, the power transmission device TM1 becomes the neutral state in which the power transmission from the first shaft 181 to the second shaft 182 is cut off. Figure 7

[0106] When the operation lever 241 of the operation mechanism 240 is in the intermediate position shown in (B) of FIG. 10, the first small-diameter portion 241b1 allows the pin 283 of the dog portion 212 to return inward in the radial direction, and at the same time the third large-diameter portion 241c3 pushes the pin 283 of the dog portion 222 outward in the radial direction, thereby setting the dog portion 212 to the engaged state and setting the dog portion 222 to the disengaged state. That is, the first power transmission path becomes the connected state, and the second power transmission path becomes the disconnected state. Thereby, the power transmission device TM1 becomes the high-speed rotation state in which the rotational power of the first shaft 181 is decelerated by the first power transmission path (the first planetary mechanism PI) and transmitted to the second shaft 182. Figure 7

[0107] When the operation lever 241 of the operation mechanism 240 is in the upper position shown in (C) of FIG. 10, the first large-diameter portion 241c1 pushes the pin 283 of the dog portion 212 outward in the radial direction, and at the same time the second small-diameter portion 241b2 allows the pin 283 of the dog portion 222 to return inward in the radial direction, thereby setting the dog portion 212 to the disengaged state and setting the dog portion 222 to the engaged state. That is, the first power transmission path becomes the disconnected state, and the second power transmission path becomes the connected state. Thereby, the power transmission device TM1 becomes the high-torque state in which the rotational power of the first shaft 181 is decelerated by the second power transmission path (the first planetary mechanism PI and the second planetary mechanism P2) and transmitted to the second shaft 182. Figure 7

[0108] ​​​In the bidirectional clutch 280 that constitutes the intermittent units 212, 222, the roller 281 is the engaging member, and the operation lever 241, the pin 283, the guide 284, and the retainer 282 correspond to the operation portion that operates the engaging member (roller 281) to the engaged state and the non-engaged state. In addition, among the elements that constitute the operation portion, the guide 284 and the retainer 282 are the action member that moves the engaging member (roller 281), and the operation lever 241 and the pin 283 correspond to the operation member that is provided so as to be able to operate the action member. The operation member can also be able to operate the engaging member (roller 281) without passing through the action member. Among the elements that constitute the action member, the pin 283 is the advance-retract member that is provided so as to be able to advance and retract in the radial direction, and the operation lever 241 corresponds to the extension portion that is provided so as to be able to advance and retract the advance-retract member (pin 283).

[0109] Thus, the transmission T of the power transmission device TM1 includes the first planetary mechanism PI and the second planetary mechanism P2, whereby it is possible to increase the speed change ratio in a small space. In particular, the second power transmission path passes through the first planetary mechanism PI in addition to the second planetary mechanism P2, and thus it is possible to effectively increase the speed change ratio.

[0110] In addition, the rotational axes of the carriers PC1, PC2 of the first planetary mechanism PI and the second planetary mechanism P2 coincide with the rotational axes of the first shaft 181 and the second shaft 182, and thus it is possible to arrange the transmission T coaxially with the first shaft 181 and the second shaft 182, and to downsize the power transmission device TM1.

[0111] In addition, the intermittent mechanism 20 is provided with the operation lever 241 that is arranged in the inside space S of the second shaft 182 in the rotational axis direction, and the first power transmission path and the second power transmission path are switched on and off based on the movement control of the operation lever 241. Thus, the intermittent mechanism 20 is concentrated on the inside of the transmission T, and it is possible to further downsize the power transmission device TM1.

[0112] In addition, in the power transmission device TM1 of the present embodiment, in the first power transmission path, the first intermittent mechanism 210 is arranged at a position on the downstream side from the first planetary mechanism PI, and in the second power transmission path, the second intermittent mechanism 220 is arranged at a position on the downstream side from the first planetary mechanism PI and the second planetary mechanism P2. Thus, in a case where power is input from the downstream side (second shaft 182), it is possible to reduce the components that are linked to rotate.

[0113] In the following description, other embodiments of the present application are described with reference to Figure 8 and the drawings hereafter. However, for structures that are common to the first embodiment, the description of the first embodiment is sometimes referred to by using the same reference numerals.

[0114] (Second Embodiment)

[0115] As described above, the power transmission device TM1 of the first embodiment includes two planetary mechanisms P1 and P2 as a transmission T, and two discontinuous mechanisms 210 and 220 as discontinuous mechanisms 20. Based on the control of the discontinuous mechanisms 210 and 220, it switches between a neutral state, a high-speed rotation state, and a high-torque state. On the other hand, as... Figure 8 As shown, the power transmission device TM2 of the second embodiment differs from that of the power transmission device TM2 of the first embodiment in that it includes a planetary mechanism P1 as a gearbox T and an intermittent mechanism 210 as an intermittent mechanism 20, and switches between a neutral state and a high-speed rotation state based on the control of the intermittent mechanism 210. According to this second embodiment, the power transmission device TM2 can be made smaller and simpler.

[0116] (Third implementation method)

[0117] like Figure 9 As shown, the power transmission device TM3 of the third embodiment differs from the power transmission device TM1 of the first embodiment in that the second shaft 182 is used as the input shaft and the first shaft 181 is used as the output shaft. Specifically, the power transmission device TM3 of the third embodiment is described as follows: the sun gear SG1 of the first planetary mechanism P1 is connected to the second shaft 182 via a first discontinuous mechanism 210. The planet carrier PC1 of the first planetary mechanism P1 and the sun gear SG2 of the second planetary mechanism P2 are integrally formed. The sun gear SG2 of the second planetary mechanism P2 is connected to the second shaft 182 via a second discontinuous mechanism 220, and the planet carrier PC2 is integrally formed with the first shaft 181.

[0118] That is, in the power transmission device TM3 of the third embodiment, when the first discontinuity mechanism 210 and the second discontinuity mechanism 220 are set to the disconnected state, a neutral state is achieved where the power transmission from the second shaft 182 to the first shaft 181 is cut off. Furthermore, when the first discontinuity mechanism 210 is set to the engaged state and the second discontinuity mechanism 220 is set to the disconnected state, a high-torque state is achieved where the rotational power of the second shaft 182 is transmitted to the first shaft 181 via the first planetary mechanism P1 and the second planetary mechanism P2. Additionally, when the first discontinuity mechanism 210 is set to the disconnected state and the second discontinuity mechanism 220 is set to the engaged state, a high-speed rotational state is achieved where the rotational power of the second shaft 182 is transmitted to the first shaft 181 via the second planetary mechanism P2. According to this third embodiment, the neutral state, the high-torque state, and the high-speed rotational state can be switched with a different configuration structure than in the first embodiment.

[0119] (Fourth Implementation)

[0120] like Figure 10As shown, the power transmission apparatus TM4 of the fourth embodiment differs from the power transmission apparatus TM1 of the first embodiment in that three planetary mechanisms P1, P2, P3 are provided as the transmission T, three intermittent mechanisms 210, 220, 230 are provided as the intermittent mechanism 20, and a neutral state and three stages of shift states (1st speed state (high torque state), 2nd speed state (medium speed rotation / medium torque state), 3rd speed state (high speed rotation state)) are provided.

[0121] Specifically, in addition to the power transmission apparatus TM1 of the first embodiment, a third planetary mechanism P3 is provided above the second planetary mechanism P2. The third planetary mechanism P3 has a sun gear SG3, a ring gear RG3, a plurality of planetary gears PG3 that mesh with the sun gear SG3 and the ring gear RG3, and a carrier PC3 that supports the planetary gears PG3 so as to be able to rotate on their own axes and revolve around the sun gear SG3. The three rotating elements consisting of the sun gear SG3, the ring gear RG3, and the carrier PC3 satisfy a collinear relationship in which their rotational speeds are always arranged on a single straight line in a speed column chart (also referred to as a column chart).

[0122] The carrier PC2 of the second planetary mechanism P2 is formed integrally with the sun gear SG3 of the third planetary mechanism P3. In the present embodiment, the sun gear SG3 is formed on an outer peripheral portion of a cylindrical portion PC2a formed integrally with the carrier PC2. Thereby, it is possible to transmit the rotational power that is decelerated by the second planetary mechanism P2 to the third planetary mechanism P3.

[0123] The sun gear SG3 (cylindrical portion PC2a) of the third planetary mechanism P3 is connected to the second shaft 182 via the second intermittent mechanism 220. Thereby, it is the same as TM1 of the first embodiment that a second power transmission path that includes the first planetary mechanism P1 and the second planetary mechanism P2 is formed.

[0124] The ring gear RG3 of the third planetary mechanism P3 is formed integrally with the housing 180. That is, the ring gear RG3 is not rotatable. In addition, the ring gear RG3 of the third planetary mechanism P3 is not necessarily formed integrally with the housing 180, but can be separate from the housing 180 and fixed to the housing 180 in a manner that is not rotatable.

[0125] Thereby, the carrier PC3 of the third planetary mechanism P3 decelerates and outputs the rotation input from the sun gear SG3.

[0126] The carrier PC3 of the third planetary mechanism P3 is connected to the second shaft 182 via a third interrupt mechanism 230. In the present embodiment, the third interrupt mechanism 230 is provided between a cylindrical portion PC3a that is formed integrally with the carrier PC3 and the second shaft 182 that is located at the inner circumferential portion of the cylindrical portion PC3a. In addition, although not illustrated, a bearing that allows relative rotation can also be provided between the rotating element of the first planetary mechanism PI and the rotating element of the second planetary mechanism P2, between the rotating element of the second planetary mechanism P2 and the rotating element of the third planetary mechanism P3, and between the housing 180 and the rotating element of the first planetary mechanism PI or the second planetary mechanism P2 or the third planetary mechanism P3.

[0127] In the transmission T thus configured, a first power transmission path is formed that transmits the power of the power source input from the first shaft 181 to the second shaft 182 via the first planetary mechanism PI and the first interrupt mechanism 210, a second power transmission path is formed that transmits the power via the first planetary mechanism PI, the second planetary mechanism P2, and the second interrupt mechanism 220 to the second shaft 182, and a third power transmission path is formed that transmits the power via the first planetary mechanism PI, the second planetary mechanism P2, the third planetary mechanism P3, and the third interrupt mechanism 230 to the second shaft 182.

[0128] The third interrupt mechanism 230 has an interrupt portion 232 provided between the cylindrical portion PC3a and the second shaft 182. The structure of the interrupt portion 232 is the same as that of the interrupt portions 212 and 222.

[0129] In the power transmission apparatus TM4 of the fourth embodiment, when the interrupt portion 212, the interrupt portion 222, and the interrupt portion 232 are set to the disengaged state, the first to third power transmission paths become the cut-off state, and a neutral state in which the transmission of the power from the first shaft 181 to the second shaft 182 is cut off is established.

[0130] In addition, when the interrupt portion 212 is set to the engaged state and the interrupt portion 222 and the interrupt portion 232 are set to the disengaged state, the first power transmission path becomes the connected state, the second power transmission path and the third power transmission path become the cut-off state, and a 3rd speed state (high-speed rotation state) in which the rotational power of the first shaft 181 is decelerated by the first power transmission path (the first planetary mechanism PI) and transmitted to the second shaft 182 is established.

[0131] In addition, when the interrupt portion 222 is set to the engaged state and the interrupt portion 212 and the interrupt portion 232 are set to the disengaged state, the second power transmission path becomes the connected state, the first power transmission path and the third power transmission path become the cut-off state, and a 2nd speed state (medium-speed rotation / medium-torque state) in which the rotational power of the first shaft 181 is decelerated by the second power transmission path (the first planetary mechanism PI and the second planetary mechanism P2) and transmitted to the second shaft 182 is established.

[0132] Furthermore, when the discontinuous section 232 is in the engaged state and the discontinuous sections 212 and 222 are in the disengaged state, the third power transmission path becomes connected, and the first and second power transmission paths become disconnected. This results in a 1-speed state (high torque state) where the rotational power of the first shaft 181 is decelerated and transmitted to the second shaft 182 via the third power transmission path (first planetary mechanism P1, second planetary mechanism P2, and third planetary mechanism P3). Thus, according to the power transmission device TM4 of the fourth embodiment, by adding a planetary mechanism (third planetary mechanism P3) and a discontinuous mechanism (third discontinuous mechanism 230) to the power transmission device TM1 of the first embodiment, an additional speed change stage can be added. Therefore, the number of speed change stages of the power transmission device TM4 can be set to 4 or more.

[0133] (A variation of the fourth embodiment)

[0134] like Figure 11 As shown, the power transmission device TM4 of the fourth embodiment has three planetary mechanisms P1, P2, and P3 as a gearbox T, and three discontinuous mechanisms 210, 220, and 230 as discontinuous mechanisms 20. It also has a neutral state and three-stage shifting states (1st speed state (high torque state), 2nd speed state (medium speed rotation / medium torque state), and 3rd speed state (high speed rotation state)), which is the same as the power transmission device TM4 of the fourth embodiment.

[0135] In the modified transmission T, the planet carrier PC1 of the first planetary mechanism P1 is integrally formed with the first shaft 181. Alternatively, the planet carrier PC1 of the first planetary mechanism P1 may not necessarily be integrally formed with the first shaft 181; it may be separate from the first shaft 181 but rotatably connected to it. Thus, the rotational power of the first shaft 181 is input to the first planetary mechanism P1. Furthermore, the sun gear SG1 of the first planetary mechanism P1 is integrally formed with the sun gear SG2 of the second planetary mechanism P2. Also, the sun gear SG1 of the first planetary mechanism P1 may not necessarily be integrally formed with the sun gear SG2 of the second planetary mechanism P2; it may be separate from the sun gear SG2 of the second planetary mechanism P2 but rotatably connected to it. Thus, the rotational power accelerated by the first planetary mechanism P1 can be transmitted to the second planetary mechanism P2. Additionally, although the illustration is omitted, bearings that allow relative rotation can be provided between the rotating elements of the first planetary mechanism P1 and the rotating elements of the second planetary mechanism P2, between the rotating elements of the second planetary mechanism P2 and the rotating elements of the third planetary mechanism P3, and between the housing 180 and the rotating elements of the first planetary mechanism P1, the second planetary mechanism P2, or the third planetary mechanism P3.

[0136] In the transmission T configured in this way, a first power transmission path is formed to transmit power from the power source input from the first shaft 181 to the second shaft 182 via the first planetary mechanism P1 and the first discontinuous mechanism 210; a second power transmission path is formed to transmit power to the second shaft 182 via the first planetary mechanism P1, the second planetary mechanism P2 and the second discontinuous mechanism 220; and a third power transmission path is formed to transmit power to the second shaft 182 via the first planetary mechanism P1, the second planetary mechanism P2, the third planetary mechanism P3 and the third discontinuous mechanism 230.

[0137] In the transmission T of this modified example, the rotation of the first shaft 181 can be set to increase speed and be transmitted to the second shaft 182 through the first power transmission path, be transmitted to the second shaft 182 at approximately constant speed through the second power transmission path, and be decelerated and transmitted to the second shaft 182 through the third power transmission path.

[0138] (Fifth Implementation)

[0139] In the following explanation, reference will be made to Figures 12 to 16 The electric prosthetic leg 1 (fifth embodiment) assembled with the power transmission device TM1 of the first embodiment will be described. Furthermore, in the following description, the forward-backward direction, left-right direction, and up-down direction are defined based on the user of the electric prosthetic leg 1. In the accompanying drawings, the front of the electric prosthetic leg is denoted as Fr, the rear as Rr, the left side as L, the right side as R, the top as U, and the bottom as D.

[0140] like Figure 12 and Figure 13 As shown, the electric prosthetic leg 1 is a prosthetic leg installed on the leg of a person without a knee. It includes: a lower knee component 110 located below the knee; an upper knee component 120 installed on the thigh and located above the knee; a knee joint mechanism 130 connecting the lower knee component 110 and the upper knee component 120 so that the included angle between them can be changed; an expansion and contraction device 200 capable of expanding and contracting the included angle between the lower knee component 110 and the upper knee component 120; and a battery B that supplies power to the expansion and contraction device 200, etc.

[0141] The upper knee component 120 includes: a connector 121 connected to a receiving cavity (not shown), an upper wall portion 125 on which the connector 121 is mounted, and a pair of left and right side wall portions (not shown) connected to the upper wall portion 125. The receiving cavity is located in the thigh portion 123 (see reference). Figure 15 , Figure 15 The upper knee component 120 is integrated with the thigh portion 123 by connecting the connector 121 to the receiving cavity.

[0142] The lower knee part 110 has a box-shaped main frame 111 with an open rear portion, a detachable rear cover 113 that covers the open rear portion of the main frame 111 in an openable and closable manner, and an adapter 122 mounted to the lower surface of the main frame 111.

[0143] The upper knee part 120 is disposed on the upper portion of the main frame 111 of the lower knee part 110 via a connecting shaft 135 that constitutes a knee joint mechanism 130, and a leg portion 114 that extends downward is connected to the adapter 122 of the main frame 111.

[0144] In the space formed by the upper knee part 120 and the lower knee part 110, an expansion and contraction device 200 that can expand and contract the included angle between the lower knee part 110 and the upper knee part 120 is provided. The expansion and contraction device 200 is configured to be able to expand and contract the included angle between the lower knee part 110 and the upper knee part 120 by the meshing of a gear.

[0145] As shown in Figs. 1 and 2, the expansion and contraction device 200 has a motor M that outputs a rotational power, a power transmission device TM1 that transmits the power of the motor M, and a bevel gear mechanism 140 that can expand and contract the included angle between the lower knee part 110 and the upper knee part 120. Figure 13 Figure 14 As shown in Figs. 1 and 2, the expansion and contraction device 200 has a motor M that outputs a rotational power, a power transmission device TM1 that transmits the power of the motor M, and a bevel gear mechanism 140 that can expand and contract the included angle between the lower knee part 110 and the upper knee part 120.

[0146] The motor M is, for example, a permanent magnet motor, and is disposed at a position lower than the power transmission device TM1. The motor M is a gear mechanism built-in motor that has a motor main body portion 171, a gear mechanism portion 172 that decelerates the output rotation of the motor main body portion 171, and an output shaft 170 that outputs the rotational power after deceleration. The output shaft 170 is a hollow cylindrical shaft that has an internal space 170a extending in the direction of the rotational axis.

[0147] The bevel gear mechanism 140 has a first bevel gear 141 disposed on the power transmission path of the motor M on the side opposite to the motor M with respect to the power transmission device TM1 and supported by the lower knee part 110, and a second bevel gear 142 that can mesh with the first bevel gear 141 to transmit rotation and is supported by the upper knee part 120.

[0148] The first bevel gear 141 is configured to be able to rotate integrally with the output element of the power transmission device TM1, i.e., the second shaft 182, described later. The first bevel gear 141 transmits the power of the motor M transmitted via the power transmission device TM1 to the second bevel gear 142.

[0149] ​The second bevel gear 142 is provided so as to be able to relatively rotate with the connecting shaft 135 and so as to be able to integrally rotate with the above-knee member 120. Thus, by the rotation of the second bevel gear 142 which engages with the first bevel gear 141, the above-knee member 120 rotates around the connecting shaft 135 as a center. Therefore, the included angle between the above-knee member 120 and the below-knee member 110 changes.

[0150] As shown in Figure 14 , the power transmission device TM1 is configured so that the rotational axis L1 of the first shaft 181 and the second shaft 182 coincides with the rotational axis L2 of the output shaft 170 of the motor M and the first bevel gear 141. The first shaft 181 is connected to the output shaft 170 of the motor M in a manner so as to be able to integrally rotate, and inputs the rotational power of the motor M to the power transmission device TM1. In addition, the second shaft 182 is connected to the first bevel gear 141 in a manner so as to be able to integrally rotate, and transmits the rotational power of the motor M after the speed change by the power transmission device TM1 to the first bevel gear 141. In addition, the operation lever 241 extends to the lower side of the motor M via the inside space 170a formed in the output shaft 170 of the motor M, and is moved by the servo motor 242 provided on the lower side of the motor M. Furthermore, as described above, the power transmission device TM1 switches the moving speed and the generated power of the extension and the bending of the knee joint mechanism 130 by having two power transmission paths having different speed change ratios.

[0151] The electric artificial leg 1 configured in this way is able to smoothly perform the stair climbing action, whereas when using the existing driven artificial leg having a driven damper, it is necessary to climb one step at a time with the non-artificial leg side leg. Figure 15 is a view showing the action of the user and the electric artificial leg 1 when climbing stairs (stair climbing action). Figure 15 (A) to (D) of are views showing the standing phase, (D) to (E) are views showing the transition phase from the standing to the pre-lifting leg phase, (E) to (G) are views showing the pre-lifting leg phase, (G) is a view showing the transition phase from the pre-lifting leg phase to the post-lifting leg phase and the post-lifting leg phase, and (H) is a view showing the transition phase from the post-lifting leg phase to the standing and the standing phase.

[0152] Specifically, as shown in Figure 15 (A) to (D), in a state where a load is applied to the electric artificial leg 1 when the electric artificial leg 1 is extended forward and steps on a step (stair climbing), a large power is required when the knee joint mechanism 130 is caused to extend from the bent state.

[0153] At this time, the power transmission device TM1 is set to Figure 7In this state, when the motor M rotates in the forward direction, the rotation of the first bevel gear 141 fixed to the lower knee member 110 is accompanied by the rotation of the second bevel gear 142 fixed to the upper knee member 120, whereby the upper knee member 120 rotates with the connecting shaft 135 as the center with respect to the lower knee member 110, and the knee joint mechanism 130 extends. Also, this extension power is a high-torque power, and thus, even in a state where a large load is applied to the motorized artificial leg 1 when the motorized artificial leg 1 is extended forward and steps on a step, the knee joint mechanism 130 can be reliably extended from the bent state.

[0154] On the other hand, in order to smoothly perform the step-up action, as Figure 15 indicated in (E) to (H) of FIG. 8, it is necessary to bend (lift up) the knee joint mechanism 130 from the extended state in a state where a load is applied to the healthy leg. When the knee joint mechanism 130 is bent from the extended state, a large power is not required, but a quick action is required.

[0155] At this time, the power transmission device TM1 is set to Figure 7 the high-speed rotation state indicated in (B) of FIG. 6. In this state, when the motor M rotates in the reverse direction, the rotation of the first bevel gear 141 fixed to the lower knee member 110 is accompanied by the rotation of the second bevel gear 142 fixed to the upper knee member 120, whereby the upper knee member 120 rotates with the connecting shaft 135 as the center with respect to the lower knee member 110, and the knee joint mechanism 130 bends. Also, this bending power is a power after high-speed rotation, and thus, the knee joint mechanism 130 can be quickly bent.

[0156] Figure 16 FIG. 7 is a diagram showing the action of the user and the motorized artificial leg when walking on a flat surface (flat surface walking action). Figure 16 (A) to (D) of FIG. 8 are diagrams showing the standing phase, (D) is a diagram showing the transition phase from the standing to the leg lifting, (E) to (H) are diagrams showing the leg lifting phase, and (H) is a diagram showing the transition phase from the leg lifting to the standing and the standing phase.

[0157] As indicated in (A) to (D) of FIG. 6, Figure 16 indicated in (A) to (D) of FIG. 6, Figure 16 indicated in (A) to (D) of FIG. 6, in a state where a load is applied to the motorized artificial leg 1 when walking on a flat surface and stepping down, the power transmission device TM1 is in Figure 7 the high-speed rotation state indicated in (B) of FIG. 6. In this state, when the motor M is set to the non-driving state, an external force in the bending direction acting on the motorized artificial leg 1 is transmitted from the bevel gear mechanism 140 to the motor M via the first planetary mechanism PI of the power transmission device TM1, and thus, by attenuating the external force in the bending direction by the friction of the motor M and the first planetary mechanism PI, it is possible to prevent so-called knee folding.

[0158] In addition, as shown in (D) to (H) of FIG. 12, in a state where a load is applied to the healthy leg, the power transmission device TM1 is set to a neutral state shown in (A) of FIG. 12. In this state, the motor M and the bevel gear mechanism 140 are in a state where power is not transmitted, and thus the user of the motorized artificial leg 1 can smoothly extend the foot. Figure 16 Figure 7

[0159] (Sixth Embodiment)

[0160] Figure 17 The motorized artificial leg 1 shown in FIG. 13 is a modification of the fifth embodiment, and differs from the fifth embodiment in that the motorized artificial leg 1 is caused to perform the flexion and extension action using a spindle unit SP instead of the bevel gear mechanism 140. The spindle unit SP has a spindle 173 formed with an external thread and a sleeve 174 formed with an internal thread, and the sleeve 174 is moved in translation along the rotation axis of the spindle 173 by the rotation of the spindle 173. Specifically, the spindle 173 is moved in rotation by the rotational power of the motor M transmitted by the power transmission device TM1. On the other hand, the sleeve 174 is supported to the lower-knee member 110 so as to be unable to rotate but able to move up and down. Thus, when the spindle 173 is rotated to one side by the rotational power of the motor M transmitted by the power transmission device TM1, the sleeve 174 is moved in translation away from the power transmission device TM1, and when the spindle 173 is rotated to the other side, the sleeve 174 is moved in translation toward the power transmission device TM1. In addition, the movement of the sleeve 174 in translation away from the power transmission device TM1 is sometimes referred to as the extension action of the spindle unit SP, and conversely, the movement of the sleeve 174 in translation toward the power transmission device TM1 is sometimes referred to as the shortening action of the spindle unit SP.

[0161] That is, the distance of the sleeve 174 from the power transmission device TM1 is extended and contracted according to the rotation direction of the spindle 173. The upper end portion of the sleeve 174 is linked to the upper-knee member 120 via a link member 175. The distance between the sleeve 174 and the power transmission device TM1 is extended and contracted according to the rotation direction of the spindle 173, whereby the lower-knee member 110 and the upper-knee member 120 are rotated about the connecting shaft 135. Thus, the included angle between the upper-knee member 120 and the lower-knee member 110 is changed. When the included angle between the upper-knee member 120 and the lower-knee member 110 is set to the acute angle side of the angles of the acute angle side and the obtuse angle side, the knee joint mechanism 130 is extended when the included angle is increased, and the knee joint mechanism 130 is flexed when the included angle is decreased.

[0162] ​​According to such a sixth embodiment, the same effects as the fifth embodiment are obtained. In addition, in the electric artificial leg 1 of the sixth embodiment, the spindle unit SP and the power transmission device TM1 are arranged so that the rotational axes (the rotational axes L1) coincide with each other. On the other hand, the motor M is arranged so that its rotational axis L2 is juxtaposed with the rotational axes L1 of the spindle unit SP and the power transmission device TM1, and inputs rotational power to the power transmission device TM1 via the spur gear mechanism GM.

[0163] (Seventh Embodiment)

[0164] Figure 18 A structure of a mobile body M1 assembled with the power transmission device TM1 of the first embodiment is shown. The mobile body M1 is provided with: a motor M; a first gear 501 that outputs rotational power of the motor M; a second gear 502 that is connected to the first shaft 181 of the power transmission device TM1 in an integrally rotatable manner, and is engaged with the first gear 501; a third gear 503 that is connected to the second shaft 182 of the power transmission device TM1 in an integrally rotatable manner, and outputs rotational power of the motor M after the speed change by the power transmission device TM1; a fourth gear 504 that is engaged with the third gear 503, and transmits rotational power to a differential device DIF; left and right axles 505 that can differentially rotate to transmit rotational power from the differential device DIF; and left and right wheels WH that are provided to the end portions of the axles 505 in an integrally rotatable manner.

[0165] According to such a mobile body M1 of the seventh embodiment, it is possible to change the speed to the neutral state, the high-speed rotation state, and the high-torque state by the power transmission device TM1.

[0166] The above-described various embodiments have been described with reference to the drawings, but the present application is of course not limited to such examples. It will be understood by those skilled in the art that various modifications or corrections can be obviously conceived within the scope of the technical idea described in the technical solution, and such modifications or corrections naturally belong to the technical scope of the present application. In addition, the respective constituent elements in the above-described embodiments can be arbitrarily combined within the scope of the gist of the present application.

[0167] In the present specification, at least the following matters are described. In addition, although the corresponding constituent elements and the like in the above-described embodiments are shown in brackets, the present application is not limited thereto.

[0168] (1) A power transmission device (power transmission devices TM1 to TM4) that is provided with an interrupt mechanism (interrupt mechanism 20) and a transmission (transmission T), in which,

[0169] The interrupt mechanism (interrupt mechanism 20, first interrupt mechanism 210) has:

[0170] a coupling member (roller 281) disposed between the first rotating body (cylinder portion PC1a) and the second rotating body (second shaft 182), and

[0171] an operation portion (operation lever 241, pin 283, holder 282, guide 284) that operates the coupling member to a coupled state in which the first rotating body and the second rotating body are integrally rotatable, and an uncoupled state in which the first rotating body and the second rotating body are relatively rotatable,

[0172] the operation portion has:

[0173] a moving member (holder 282, guide 284) that moves the coupling member, and

[0174] an operation member (operation lever 241, pin 283) that is provided so as to be able to operate the coupling member via the moving member, or so as to be able to operate the coupling member without the moving member,

[0175] the first rotating body and the second rotating body are disposed so that their rotational axes (rotational axis L1) coincide with each other and at least a portion of each overlaps the other when viewed in the radial direction with respect to the rotational axis,

[0176] the operation member has:

[0177] a moving member (holder 282, guide 284) that moves the coupling member, and

[0178] an extension portion (operation lever 241) that is provided so as to extend along the rotational axis and be able to move in the radial direction with respect to the rotational axis,

[0179] the transmission has a speed change portion (second planetary mechanism P2) that has a first rotating element (sun gear SG2) constituted by the first rotating body or a rotating body that rotates integrally with the first rotating body, a second rotating element (carrier PC2) provided so as to be able to transmit rotation to the first rotating element, and a third rotating element (ring gear RG2) provided so as to be able to transmit rotation to the second rotating element,

[0180] the second rotating element and the third rotating element are disposed at a position that is further outward in the radial direction than the second rotating body, and are disposed so as to at least partially overlap the second rotating body when viewed in the radial direction.

[0181] According to (1), the transmission is concentrated around the second rotating body, and the power transmission device can be downsized.

[0182] (2) The power transmission device according to (1), wherein

[0183] The advancing / retracting member is configured such that its inner end, located on the radial side of the rotation axis, abuts against the extension.

[0184] According to (2), the inner end of the advancing / retracting member abuts against the extension of the operating member, thereby enabling the advancing / retracting member to move forward and backward along an orthogonal direction that is orthogonal to the rotation axes of the first and second rotating bodies.

[0185] (3) The power transmission device according to (1) or (2), wherein,

[0186] The power transmission device also includes a third rotating body (cylinder PC2a) and a fourth rotating body (second shaft 182) configured with their rotation axes aligned with the rotation axis.

[0187] The intermittent mechanism (intermittent mechanism 20, second intermittent mechanism 220) further includes:

[0188] Other engaging components (rollers 281) are disposed between the third rotating body and the fourth rotating body; and

[0189] Other operating parts (operating lever 241, pin 283, retainer 282, guide 284) operate the other engaging parts to an engaged state in which the third rotating body and the fourth rotating body can rotate together, and to a non-engaged state in which the third rotating body and the fourth rotating body can rotate relative to each other.

[0190] According to (3), by controlling other engaging parts by other operating units, it is possible to appropriately switch between the engaging state of the third rotating body and the fourth rotating body and the non-engaging state of the third rotating body and the fourth rotating body.

[0191] (4) The power transmission device according to (3), wherein,

[0192] The other operating units have:

[0193] Other actuators (retainer 282, guide 284) that move the other engaging members; and

[0194] Other operating elements (operating lever 241, pin 283) are configured to operate the other engaging elements via the other operating elements, or to operate the other engaging elements without the other operating elements.

[0195] According to (4), by controlling other action components with other operation components, it is possible to appropriately switch between the engaged state of the third rotating body and the fourth rotating body and the unengaged state of the third rotating body and the fourth rotating body.

[0196] (5) The power transmission device according to (4), wherein,

[0197] The other operation member has:

[0198] an other advancing / retracting member (pin 283) disposed so as to be able to advance and retract in an orthogonal direction orthogonal to the rotation axis, and

[0199] an other extension (operation lever 241) disposed so as to extend along the rotation axis and be able to advance and retract along the rotation axis.

[0200] According to (5), by the other extension controlling the other advancing / retracting member, the other advancing / retracting member is able to advance and retract in an orthogonal direction orthogonal to the rotation axes of the third and fourth rotating bodies.

[0201] (6) The power transmission device according to (5), wherein

[0202] the second rotating body and the fourth rotating body are disposed so as to be able to rotate integrally,

[0203] the extension and the other extension are disposed integrally and are disposed so as to be located at different positions in the direction of the rotation axis.

[0204] According to (6), the drive sources of the second and fourth rotating bodies can be shared, and control can be simplified.

[0205] (7) The power transmission device according to (5) or (6), wherein

[0206] the other advancing / retracting member is disposed so that an inner end of the other advancing / retracting member on the side of the rotation axis in the radial direction abuts against the other extension.

[0207] According to (7), the inner end of the other advancing / retracting member abuts against the other extension of the other operation member, and thus the other advancing / retracting member is able to advance and retract in an orthogonal direction orthogonal to the rotation axes of the third and fourth rotating bodies.

[0208] (8) The power transmission device according to any one of (3) to (7), wherein

[0209] the third rotating body is formed integrally with the second rotating element, or is mechanically connected to the second rotating element in a manner so as to be able to rotate integrally.

[0210] According to (8), the rotation after the speed change by the speed change portion is transmitted to the third rotating body.

[0211] (9) The power transmission device according to any one of (1) to (8), wherein

[0212] The transmission has another shift section (first planetary mechanism P1) that has another first rotary element (sun gear SG1), another second rotary element (carrier PC1) disposed so as to be able to transmit rotation with the other first rotary element, and another third rotary element (ring gear RG1) disposed so as to be able to transmit rotation with the other second rotary element,

[0213] The other second rotary element of the other shift section is formed integrally with the first rotary element of the shift section, or is mechanically connected to the first rotary element of the shift section in a manner that allows integral rotation.

[0214] According to (9), rotation after shifting by the other shift section is transmitted to the shift section.

[0215] (10) A power transmission device (power transmission devices TM1 to TM4) that has an intermittent mechanism (intermittent mechanism 20) and a transmission (transmission T), in which

[0216] The intermittent mechanism has:

[0217] An engagement member (roller 281) disposed between a first rotary body (sun gear SG2) and a second rotary body (second shaft 182), and

[0218] An operation section (operation lever 241, pin 283, holder 282, guide 284) that operates the engagement member to an engaged state in which the first rotary body and the second rotary body are able to rotate integrally, and a non-engaged state in which the first rotary body and the second rotary body are able to rotate relatively,

[0219] The operation section has a moving member (holder 282, guide 284) that moves the engagement member, and an operation member (operation lever 241, pin 283) disposed so as to be able to operate the engagement member via the moving member, or so as to be able to operate the engagement member without the moving member,

[0220] The first rotary body and the second rotary body are disposed so that their rotational axes (rotational axis L1) coincide with each other and at least a portion of each overlaps the other when viewed in the radial direction with respect to the rotational axis,

[0221] The operation member has:

[0222] A moving-back-and-forth member (pin 283) disposed so as to be able to move back and forth along the radial direction, and

[0223] An extension section (operation lever 241) disposed so as to extend along the rotational axis and be able to move back and forth along the rotational axis,

[0224] The transmission has a planetary transmission section (second planetary mechanism P2) having a first rotary element (sun gear SG2), a third rotary element (ring gear RG2), a fourth rotary element (planetary gear PG2) disposed between the first rotary element and the third rotary element in a manner capable of transmitting power between the first rotary element and the third rotary element, and a second rotary element (carrier PC2) that supports the fourth rotary element so as to be capable of rotating about its own axis and revolving about the first rotary element, the planetary transmission section being configured to satisfy a collinear relationship in which rotational speeds of three rotary elements constituted by the first rotary element, the third rotary element, and the second rotary element are arranged on a single straight line in a nomograph,

[0225] The rotational axis of the third rotary element of the planetary transmission section coincides with the rotational axes of the first rotary body and the second rotary body.

[0226] According to (10), the transmission can be disposed coaxially with the rotational axes of the first rotary body and the second rotary body, and the power transmission device can be downsized.

[0227] (11) The power transmission device according to (10), wherein

[0228] Power of a power source (motor M) is input to the first rotary element of the planetary transmission section,

[0229] The power source includes an electric motor having a rotational axis (rotational axis L2) that coincides with the rotational axes of the first rotary body and the second rotary body.

[0230] According to (11), the power source can also be disposed coaxially with the rotational axes of the first rotary body and the second rotary body.

[0231] (12) A joint device (electric artificial leg 1) including:

[0232] a first member (below-knee member 110);

[0233] a second member (above-knee member 120);

[0234] a connecting portion (knee joint mechanism 130) that connects the first member and the second member in a manner capable of changing an included angle between the first member and the second member; and

[0235] an expansion / contraction device (expansion / contraction device 200) capable of expanding and contracting the included angle between the first member and the second member, wherein

[0236] The expansion / contraction device includes the power transmission device (power transmission devices TM1 to TM3) according to any one of (1) to (10).

[0237] According to (12), the joint device can be downsized.

[0238] (13) A joint device (electric artificial leg 1) including:

[0239] a first member (below-knee member 110);

[0240] a second member (above-knee member 120);

[0241] a connecting portion (knee joint mechanism 130) that connects the first member and the second member in a manner that allows a change in an included angle between the first member and the second member; and

[0242] an expansion / contraction device (expansion / contraction device 200) that can expand and contract the included angle between the first member and the second member, wherein

[0243] the expansion / contraction device has a power source (motor M) and a power transmission device (power transmission devices TM1 to TM4) that transmits power of the power source,

[0244] the power transmission device has:

[0245] a first power transmission path that transmits the power at a first speed change ratio; and

[0246] a second power transmission path that transmits the power at a second speed change ratio different from the first speed change ratio,

[0247] the expansion / contraction device has:

[0248] a first interrupt mechanism (first interrupt mechanism 210) that switches between interruption and connection of the power on the first power transmission path; and

[0249] a second interrupt mechanism (second interrupt mechanism 220) that switches between interruption and connection of the power on the second power transmission path,

[0250] the first power transmission path includes a planetary gear portion (first planetary mechanism P1),

[0251] the second power transmission path includes the planetary gear portion and another planetary gear portion (second planetary mechanism P2) different from the planetary gear portion.

[0252] According to (13), by using a planetary gear portion for speed change, it is possible to increase the speed change ratio while downsizing. In addition, in the second power transmission path, the planetary gear portion of the first power transmission path is further passed in addition to the other planetary gear portion, and thus it is possible to effectively increase the speed change ratio.

[0253] (14) The joint device according to (13), wherein

[0254] The planetary gear section and the other planetary gear section each have a planetary gear section (first planetary mechanism P1, second planetary mechanism P2) configured to satisfy a collinear relationship in which rotational speeds of three rotating elements composed of a first rotating element (sun gear SG1, SG2), a second rotating element (planetary carrier PC1, PC2), and a third rotating element (ring gear RG1, RG2) are arranged on a single straight line in a nomograph.

[0255] The other second rotating element of the other planetary gear section is formed integrally with or is mechanically connected to the first rotating element of the planetary gear section in a manner that allows integral rotation.

[0256] According to (14), rotation after being speed-changed by the other planetary gear section can be transmitted to the planetary gear section.

[0257] (15) The joint device according to (14), wherein

[0258] In the first power transmission path, the first intermittent mechanism is disposed at a position on a downstream side from the planetary gear section,

[0259] In the second power transmission path, the second intermittent mechanism is disposed at a position on a downstream side from the planetary gear section and the other planetary gear section.

[0260] According to (15), in a case where power is input from the downstream side, components that are linked to rotate can be reduced.

[0261] (16) The joint device according to (15), wherein

[0262] When the first intermittent mechanism is in the connected state and the second intermittent mechanism is in the disconnected state, the power is output via the other planetary gear section and the first intermittent mechanism,

[0263] When the first intermittent mechanism is in the disconnected state and the second intermittent mechanism is in the connected state, the power is output via the other planetary gear section, the planetary gear section, and the second intermittent mechanism.

[0264] According to (16), by controlling the first intermittent mechanism and the second intermittent mechanism, appropriate switching of the first power transmission path and the second power transmission path can be performed.

[0265] Furthermore, this application is based on Japanese Patent Application (Patent Application No. 2023-058069) filed on March 31, 2023, the content of which is incorporated herein by reference.

[0266] Reference Signs

[0267] 1: Electric artificial leg (joint device)

[0268] 20: Intermittent mechanism

[0269] 110: Below-knee side member (first member)

[0270] 120: Above-knee side member (second member)

[0271] 130: Knee joint mechanism (connection portion)

[0272] 182: Second shaft (second rotary body, fourth rotary body)

[0273] 200: Expansion and contraction device

[0274] 210: First intermittent mechanism (intermittent mechanism)

[0275] 220: Second intermittent mechanism (intermittent mechanism)

[0276] 241: Operating lever (extension, other extension, operating member, other operating member, operating portion)

[0277] 281: Roller (engagement member)

[0278] 282: Retainer (action member, other action member, operating portion)

[0279] 283: Pin (advance and retreat member, other advance and retreat member, operating member, other operating member, operating portion)

[0280] 284: Guide member (action member, other action member, operating portion)

[0281] TM1 to TM4: Power transmission device

[0282] P1: First planetary mechanism (other speed change portion, other planetary speed change portion)

[0283] P2: Second planetary mechanism (speed change portion, planetary speed change portion)

[0284] SG1: Sun gear (other first rotary element)

[0285] SG2: Sun gear (first rotary element)

[0286] RG1: Ring gear (other third rotary element)

[0287] RG2: Ring gear (third rotary element)

[0288] PC1: Carrier (other second rotary element)

[0289] PC1a: Cylinder portion (first rotating body)

[0290] PC2: Carrier (second rotating element)

[0291] PC2a: Cylinder portion (third rotating body)

[0292] PG2: Planetary gear (fourth rotating element)

[0293] M: Motor (power source)

[0294] L1: Rotational axis

[0295] L2: Rotational axis

[0296] T: Transmission

Claims

1. A power transmission apparatus provided with a discontinuous mechanism and a transmission, wherein the discontinuous mechanism has: an engaging member disposed between a first rotating body and a second rotating body; and an operation portion that operates the engaging member into an engaging state in which the first rotating body and the second rotating body can rotate integrally, and a non-engaging state in which the first rotating body and the second rotating body can rotate relatively, the operation portion has: a moving member that moves the engaging member; and an operation member that is provided so as to be able to operate the engaging member via the moving member, or so as to be able to operate the engaging member without passing through the moving member, the first rotating body and the second rotating body are disposed so as to have axes of rotation that coincide with each other and so as to have at least a portion of each that overlaps the other when viewed in a radial direction with respect to the axes of rotation, the operation member has: a moving-back-and-forth member that is provided so as to be able to move back and forth in the radial direction; and an extension portion that is provided so as to extend along the axis of rotation and so as to be able to move back and forth along the axis of rotation, the transmission has a transmission portion that has: a first rotating element that is constituted by the first rotating body or a rotating body that rotates integrally with the first rotating body; a second rotating element that is provided so as to be able to transmit rotation to the first rotating element; and a third rotating element that is provided so as to be able to transmit rotation to the second rotating element, the second rotating element and the third rotating element are disposed at a position that is further outward in the radial direction than the second rotating body, and are disposed so as to at least partially overlap the second rotating body when viewed in the radial direction.

2. The power transmission apparatus according to claim 1, wherein an end portion, which is an inner end, of the moving-back-and-forth member on the side of the axis of rotation abuts against the extension portion.

3. The power transmission apparatus according to claim 1 or 2, wherein the power transmission apparatus is further provided with a third rotating body and a fourth rotating body that are disposed so as to have axes of rotation that coincide with the axis of rotation, the discontinuous mechanism further has: another engaging member disposed between the third rotating body and the fourth rotating body; and another operation portion that operates the other engaging member into an engaging state in which the third rotating body and the fourth rotating body can rotate integrally, and a non-engaging state in which the third rotating body and the fourth rotating body can rotate relatively.

4. The power transmission apparatus according to claim 3, wherein the other operation portion has: another moving member that moves the other engaging member; and another operation member that is provided so as to be able to operate the other engaging member via the other moving member, or so as to be able to operate the other engaging member without passing through the other moving member.

5. The power transmission apparatus according to claim 4, wherein the other operation member has: another moving-back-and-forth member that is provided so as to be able to move back and forth in an orthogonal direction that is orthogonal to the axis of rotation; and another extension portion that is provided so as to extend along the axis of rotation and so as to be able to move back and forth along the axis of rotation.

6. The power transmission apparatus according to claim 5, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The second rotating body and the fourth rotating body are configured to be able to rotate integrally, The extension portion is integrally provided with the other extension portion and is disposed at a different position in the direction of the rotation axis.

7. The power transmission apparatus according to claim 5 or 6, wherein The other advancing / retracting member is disposed so that an inner end thereof on the side of the rotation axis in the radial direction abuts against the other extension portion.

8. The power transmission apparatus according to any one of claims 3 to 7, wherein The third rotating body is integrally formed with the second rotating element or is mechanically connected to the second rotating element in a manner that enables integral rotation.

9. The power transmission apparatus according to any one of claims 1 to 8, wherein The transmission has a further transmission portion having: a further first rotating element; a further second rotating element configured to be able to transmit rotation to the further first rotating element; and a further third rotating element configured to be able to transmit rotation to the further second rotating element, The further second rotating element of the further transmission portion is integrally formed with the first rotating element of the transmission portion or is mechanically connected to the first rotating element of the transmission portion in a manner that enables integral rotation.

10. A power transmission apparatus including a discontinuous mechanism and a transmission, wherein The discontinuous mechanism has: an engaging member disposed between a first rotating body and a second rotating body; and an operation portion that operates the engaging member to a state in which the first rotating body and the second rotating body are able to rotate integrally and a state in which the first rotating body and the second rotating body are able to rotate relatively, The operation portion has: a moving member that moves the engaging member; and an operation member configured to be able to operate the engaging member via the moving member or to be able to operate the engaging member without the moving member, The first rotating body and the second rotating body are disposed so that their rotation axes coincide with each other and at least a part of each of them overlaps the other when viewed in the radial direction with respect to the rotation axis, The operation member has: an advancing / retracting member configured to be able to move in the radial direction; and an extension portion configured to extend along the rotation axis and to be able to move in the rotation axis direction, The transmission has a planetary transmission portion having a first rotating element, a third rotating element, a fourth rotating element disposed between the first rotating element and the third rotating element in a manner that enables power transmission between the first rotating element and the third rotating element, and a second rotating element that supports the fourth rotating element so as to be able to rotate on its own axis and revolve around the axis, the planetary transmission portion being configured to satisfy a collinear relationship in which rotation speeds of three rotating elements constituted by the first rotating element, the third rotating element, and the second rotating element are arranged on a single straight line in a nomograph, The rotation axis of the third rotating element of the planetary transmission portion coincides with the rotation axes of the first rotating body and the second rotating body.

11. The power transmission apparatus according to claim 10, wherein power of a power source is input to the first rotary element of the planetary gear unit, the power source includes a motor having a rotational axis aligned with the rotational axes of the first and second rotary bodies.

12. A joint device comprising: a first member; a second member; a connecting portion connecting the first member and the second member in a manner that allows an included angle between the first member and the second member to be changed; and an expansion / contraction device capable of expanding and contracting the included angle between the first member and the second member, wherein the expansion / contraction device includes the power transmission device according to any one of claims 1 to 10.

13. A joint device comprising: a first member; a second member; a connecting portion connecting the first member and the second member in a manner that allows an included angle between the first member and the second member to be changed; and an expansion / contraction device capable of expanding and contracting the included angle between the first member and the second member, wherein the expansion / contraction device has a power source and a power transmission device that transmits power of the power source, the power transmission device has: a first power transmission path that transmits the power at a first transmission ratio; and a second power transmission path that transmits the power at a second transmission ratio different from the first transmission ratio, the expansion / contraction device has: a first interrupting mechanism that switches between cutting off and connecting the power on the first power transmission path; and a second interrupting mechanism that switches between cutting off and connecting the power on the second power transmission path, the first power transmission path includes a planetary gear unit, the second power transmission path includes the planetary gear unit and another planetary gear unit different from the planetary gear unit.

14. The joint device according to claim 13, wherein the planetary gear unit and the other planetary gear unit each have a planetary gear unit configured to satisfy a collinear relationship in which rotational speeds of three rotary elements constituted by a first rotary element, a second rotary element, and a third rotary element are arranged on a single straight line on a nomograph, the other second rotary element of the other planetary gear unit is formed integrally with or is mechanically connected to the first rotary element of the planetary gear unit in a manner that allows the first rotary element and the other second rotary element to rotate integrally.

15. The joint device according to claim 14, wherein in the first power transmission path, the first interrupting mechanism is disposed at a position on a downstream side from the planetary gear unit, in the second power transmission path, the second interrupting mechanism is disposed at a position on a downstream side from the planetary gear unit and the other planetary gear unit.

16. The joint device according to claim 15, wherein when the first interrupting mechanism is in a connected state and the second interrupting mechanism is in a cut-off state, the power is output via the other planetary gear unit and the first interrupting mechanism, when the first interrupting mechanism is in a cut-off state and the second interrupting mechanism is in a connected state, the power is output via the other planetary gear unit, the planetary gear unit, and the second interrupting mechanism.

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