Coupling Device

Abstract

To provide a joint device capable of bending or spreading an articulated section, and generating a resistance when the articulated section is bent or spread.SOLUTION: An electrically-driven prosthetic foot 1 includes an under-knee side member 10, an upper-knee side member 20, a knee joint mechanism 30 for connecting so that an angle formed between the under-knee side member 10 and the upper-knee side member 20 can be changed, and an expansion device 40 capable of changing the angle formed between the under-knee side member 10 and the upper-knee side member 20 by being expanded and contracted. The expansion device 40 includes a motor M, and a power transmission path for transmitting power of the motor M. An attenuation part 100 for attenuating motion of the power transmission path is connected to the power transmission path.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a coupling device. [Background technology]

[0002] Conventionally, a known joint device used in a joint connecting two members includes an extension device that can change the angle between the two members. One example of such a joint device is a prosthetic leg used in a knee joint. Patent Document 1 describes a method in which a sensor that detects the contraction movement of the muscles in the stump of the amputated leg is provided in the femoral socket of the prosthetic leg attached to the stump of the amputated leg, and the throttle of a variable valve of a hydraulic cylinder that adjusts the resistance of flexion and extension of the knee joint is controlled based on the detection information from the sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-19105 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the prosthetic leg described in Patent Document 1 is capable of generating resistance to flexion or extension, but is unable to flex or extend the knee joint.

[0005] The present invention provides a joint device that allows for flexion or extension of an articulation section, and that is capable of generating resistance when the articulation section is extended or flexed. [Means for solving the problem]

[0006] The present invention provides A first member; A second member; a connecting portion that connects the first member and the second member so as to change the angle between them; A joint device including an extension device that can change the angle formed between the first member and the second member by extending and contracting, The telescopic device is A power source and a power transmission unit that transmits power from the power source, The power transmission unit is a power transmission path that transmits the power of the power source; before Inscription a damping section connected to the power transmission path and configured to damp the motion of the power transmission path; and, Equipped with 、 The power source generates rotational power, The damping unit is a rotary damper that is provided to damp the rotational power transmitted to the power transmission path, includes a damper body and a rotary shaft, and is provided to apply a predetermined rotational resistance to the relative rotation between the damper body and the rotary shaft. . [Effects of the Invention]

[0007] According to the present invention, the connecting portion can be bent or extended by the power source, and the damping portion can generate resistance when the connecting portion is extended or bent. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of an electric prosthetic leg 1 according to a first embodiment of the present invention, as seen obliquely from the front. [Figure 2] FIG. 2 is a perspective view of the electric prosthetic leg 1 of FIG. 1, seen obliquely from behind. [Figure 3] FIG. 2 is a diagram showing the internal structure of the electric prosthetic leg 1 of FIG. [Figure 4] FIG. 2 is an enlarged view of a power transmission section of the electric prosthetic leg 1 of FIG. [Figure 5A] 5 is a diagram illustrating power transmission in the power transmission unit of FIG. 4 when the power transmission unit is in a first speed change state. [Figure 5B] 5 is a diagram illustrating power transmission in the power transmission unit of FIG. 4 when the power transmission unit is in a second speed change state. [Figure 5C] 5 is a diagram illustrating power transmission in the power transmission unit of FIG. 4 when the power transmission unit is in a free state. [Figure 6] 10A and 10B are diagrams illustrating the power that extends the knee joint mechanism 30 from a bent state when climbing stairs. [Figure 7] 10A and 10B are diagrams illustrating the power required to bend the knee joint mechanism 30 from an extended state when climbing stairs. [Figure 8] FIG. 10 is a perspective view of a power transmission section of an electric prosthetic leg 1 according to a second embodiment of the present invention. [Figure 9] FIG. 9 is a cross-sectional view of the power transmission section of FIG. 8. [Figure 10] FIG. 2 is an exploded perspective view of the damping unit 100 and the damping operating unit 200 common to the electric prosthetic leg 1 of each embodiment of the present invention. [Figure 11] 10(A) to 10(E) are diagrams showing the movement of the electrically powered prosthetic leg 1 when walking on flat ground. [Figure 12] FIG. 12 is a side view of the electric prosthetic leg 1 in the state shown in FIG. 11(A). DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, each embodiment of an electric prosthetic leg as an example of a joint device of the present invention will be described with reference to the drawings. In the following description, the front-to-back direction, left-to-right direction, and up-to-down direction are defined based on the user of the electric prosthetic leg. In the drawings, the front of the electric prosthetic leg is indicated 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.

[0010] First Embodiment [Electric prosthetic limb] As shown in Figures 1 to 3, the electric prosthetic leg 1 of this embodiment is a prosthetic leg for people without knees, and comprises a below-knee member 10 located below the knee, an above-knee member 20 located above the knee, a knee joint mechanism 30 that connects the below-knee member 10 and the above-knee member 20 so that the angle between them can be changed, and an extension / retraction device 40 that can change the angle between the below-knee member 10 and the above-knee member 20 by extending and retracting.

[0011] The upper-knee member 20 has an upper wall portion 22 provided with an adapter 21 that connects to a socket (not shown), and a pair of upper side walls 23 that extend downward from both the left and right ends of the upper wall portion 22, and has an approximately U-shape that opens downward when viewed from the front-to-back direction.

[0012] The knee below-side component 10 comprises a lower wall portion 12 on which the leg portion 11 is provided, and a pair of lower side wall portions 13 extending upward from both the left and right ends of the lower wall portion 12, and has an approximately U-shape that opens upward when viewed from the front-to-back direction.

[0013] A pair of lower side walls 13 of the knee below member 10 are connected between a pair of upper side walls 23 of the knee above member 20 so as to be rotatable around the rotating parts 35. This mechanism allows the angle formed between the knee below member 10 and the knee above member 20 to be changed, thereby forming the knee joint mechanism 30.

[0014] In the space formed between the knee-upper side member 20 and the knee-lower side member 10, an extension device 40 capable of changing the angle formed by the knee-lower side member 10 and the knee-upper side member 20 is provided.

[0015] 4, the extension device 40 includes a motor M that outputs rotational power, and a power transmission unit that transmits the power of the motor M. The power transmission unit includes a transmission T, a first spindle unit SP1 that is connected to the transmission T so as to be able to transmit power and that converts the rotational power output from the transmission T into translational motion, a connecting / disconnecting mechanism 50 that is interposed between the motor M and a first speed change mechanism T1 and a second speed change mechanism T2 of the transmission T, which will be described later, and a second spindle unit SP2 that converts the rotational power output from the motor M into translational motion of an actuator 55 of the connecting / disconnecting mechanism 50. Note that if power transmission members such as gears are provided downstream of the first spindle unit SP1 as viewed from the motor M, these power transmission members are also included in the power transmission unit, and all of the power transmission members form a power transmission path.

[0016] The transmission T is equipped with a transmission case 60 having a rectangular shape when viewed from the front-to-rear direction, and including a top plate 61, a bottom plate 62, and a pair of side plates 63 connecting the left and right ends of the top plate 61 and the bottom plate 62. The transmission case 60 has a pair of rotating wings 64 extending downward from the bottom plate 62, which are supported immovably but swingably about a lower swing part 70 by a swing support wall 14 extending upward from the lower wall 12 of the knee below member 10.

[0017] The motor M is disposed in front of and above the top plate 61 of the transmission case 60 so that the output shaft 71 passes through the top plate 61 and protrudes into the interior of the transmission case 60. The first spindle unit SP1 is disposed on the opposite side of the motor M in the front-to-rear direction, with the interrupting mechanism 50 sandwiched between them. In other words, the motor M is disposed forward of the interrupting mechanism 50 in the front-to-rear direction, and the first spindle unit SP1 is disposed rearward of the interrupting mechanism 50 in the front-to-rear direction. As a result, even when the motor M is mounted on the electric prosthetic leg 1, it is possible to prevent the electric prosthetic leg 1 from becoming larger in the width direction while maintaining balance in the front-to-rear direction.

[0018] The second spindle unit SP2, which converts the rotational power output from the motor M into translational motion of the actuator 55 of the interrupter mechanism 50, is disposed between the motor M and the first spindle unit SP1 in the front-to-rear direction. The output shaft 71 of the motor M, the first spindle 73 of the first spindle unit SP1, and the second spindle 75 of the second spindle unit SP2 are disposed parallel to one another and are oriented in the up-down direction when the knee joint mechanism 30 is fully extended.

[0019] The first spindle unit SP1 has a first spindle 73 formed with a male thread 73a and a sleeve 74 formed with a female thread 74a. Rotation of the first spindle 73 causes the sleeve 74 to translate along the axis of the first spindle 73. In this embodiment, the first spindle 73 receives rotational power from the motor M transmitted by the transmission T to perform rotational motion. Meanwhile, the sleeve 74 is immovably attached to a pair of inner side walls 24 extending downward from the upper wall 22 of the above-knee member 20 so as to be able to swing about the upper swing portion 25. Therefore, when the first spindle 73 receives rotational power from the motor M transmitted by the transmission T to rotate in one direction (the direction of arrow D1 in FIG. 5A), the sleeve 74 translates away from the transmission T. When the first spindle 73 rotates in the other direction (the direction of arrow D2 in FIG. 5B), the sleeve 74 translates toward the transmission T.

[0020] That is, the distance between the sleeve 74 and the transmission T expands or contracts depending on the rotation direction of the first spindle 73. Because the sleeve 74 is immovably attached to the above-knee member 20 as described above, the distance between the sleeve 74 and the transmission T expands or contracts depending on the rotation direction of the first spindle 73, causing the below-knee member 10, to which the transmission T is attached, and the above-knee member 20, to which the sleeve 74 is attached, to rotate about the rotating part 35. This changes the angle formed between the above-knee member 20 and the below-knee member 10.

[0021] As shown in FIG. 4, the transmission T includes an output gear 72 provided on the output shaft 71 of the motor M, an input gear 77 provided at approximately the center of the second spindle 75 of the second spindle unit SP2 and meshing with the output gear 72, a first transmission mechanism T1, and a second transmission mechanism T2.

[0022] The first transmission mechanism T1 is composed of a first drive gear 78 that is immovably mounted above the second spindle 75 of the second spindle unit SP2, and a first driven gear 79 that is mounted on the first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73 and that meshes with the first drive gear 78.

[0023] The second transmission mechanism T2 is composed of a second drive gear 80 that is immovably mounted below the second spindle 75 of the second spindle unit SP2, and a second driven gear 81 that is mounted on the first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73 and that meshes with the second drive gear 80.

[0024] The first transmission mechanism T1 transmits the power of the motor M at a first transmission ratio. The second transmission mechanism T2 transmits the power of the motor M at a second transmission ratio different from the first transmission ratio. By providing two power transmission paths with different transmission ratios, it is possible to switch the movement speed and generated power of the extension and flexion in the knee joint mechanism 30. As long as the first transmission ratio and the second transmission ratio are different, one of the first transmission mechanism T1 and the second transmission mechanism T2 may be a speed-reduction mechanism and the other an accelerating mechanism, one may be a constant speed mechanism and the other a speed-reduction mechanism or an accelerating mechanism, or both may be speed-reduction mechanisms or both may be accelerating mechanisms.

[0025] When the first speed change ratio is defined as the ratio of the post-shift rotational speed, which is the rotational speed on the opposite side of the motor M (first spindle unit SP1 side) in the first speed change mechanism T1, to the pre-shift rotational speed, which is the rotational speed on the motor M side in the first speed change mechanism T1, and the second speed change ratio is defined as the ratio of the post-shift rotational speed, which is the rotational speed on the opposite side of the motor M (first spindle unit SP1 side) in the second speed change mechanism T2, to the pre-shift rotational speed, which is the rotational speed on the motor M side in the second speed change mechanism T2, it is preferable that the first speed change ratio be configured to be smaller than the second speed change ratio.

[0026] For example, when the first speed change ratio of the first transmission mechanism T1 is smaller than 1, the rotation speed on the side opposite the motor M (the side of the first spindle unit SP1) decreases compared to the rotation speed on the side of the motor M, resulting in an increase in torque. When the second speed change ratio of the second transmission mechanism T2 is greater than 1, the rotation speed on the side opposite the motor M (the side of the first spindle unit SP1) increases compared to the rotation speed on the side of the motor M, resulting in a decrease in torque. In this case, the first drive gear 78 has a smaller diameter than the second drive gear 80, allowing the first drive gear 78 and the motor M to be disposed in close proximity to each other. In this embodiment, the first transmission mechanism T1 is disposed closer to the motor M than the second transmission mechanism T2. More specifically, the motor M is disposed in front of the first drive gear 78 so as to overlap with the first drive gear 78 in the vertical direction.

[0027] The first speed change mechanism T1 and the second speed change mechanism T2 are switched by an interrupting mechanism 50. The interrupting mechanism 50 includes an upper clutch 50U interposed between the motor M and the first speed change mechanism T1, a lower clutch 50D interposed between the motor M and the second speed change mechanism T2, and an actuator 55 that rotates integrally with the input gear 77.

[0028] The upper clutch 50U is a dog clutch that includes a first engaging element 51 that is an engaging element on the motor M side and a second engaging element 52 that is an engaging element on the first speed change mechanism T1 side. Explaining in more detail, the first engaging element 51 is provided above the actuator 55 and the input gear 77 so as to rotate integrally with the input gear 77. The second engaging element 52 is provided below the first drive gear 78 so as to be engageable with the first engaging element 51 and to rotate integrally with the first drive gear 78. The second engaging element 52 and the first drive gear 78 are attached above the second spindle 75 of the second spindle unit SP2 so as to be rotatable relative to the second spindle 75 but not movable.

[0029] The lower clutch 50D is a dog clutch that includes a third engaging element 53 that is an engaging element on the motor M side, and a fourth engaging element 54 that is an engaging element on the second speed change mechanism T2 side. Explaining in more detail, the third engaging element 53 is provided below the actuator 55 and the input gear 77 so as to rotate integrally with the input gear 77. The fourth engaging element 54 is provided above the second drive gear 80 so as to be engageable with the third engaging element 53 and to rotate integrally with the second drive gear 80. The fourth engaging element 54 and the second drive gear 80 are attached below the second spindle 75 of the second spindle unit SP2 so as to be rotatable relative to the second spindle 75 but not movable.

[0030] As described above, the actuator 55 is attached to the input gear 77 so as to rotate integrally therewith, and the first engaging element 51 and the third engaging element 53 are attached to the upper and lower parts of the actuator 55 so as to rotate integrally therewith. The actuator 55 is disposed approximately in the center of the second spindle 75, that is, between the first drive gear 78 and the second drive gear 80 in the up-down direction. Here, the actuator 55 is the screw nut 76 of the second spindle unit SP2. The second spindle unit SP2 has the second spindle 75 having an external thread formed thereon and the screw nut 76 (actuator 55) having an internal thread formed thereon, and as the input gear 77 rotates, the screw nut 76 (actuator 55) moves in translation while rotating along the axis of the second spindle 75.

[0031] When the motor M rotates in a first direction (the direction of arrow D1 in FIG. 5A), the screw nut 76 (actuator 55) moves upward in the vertical direction, which is the movement direction of the translational motion, and when the motor M rotates in a second direction (the direction of arrow D2 in FIG. 5B), which is opposite to the first direction, the screw nut 76 (actuator 55) moves downward in the vertical direction. In this way, by changing the rotation direction of the motor M, the movement direction of the actuator 55 can be changed.

[0032] The interrupting mechanism 50 can be in three states: a first speed-changing state, a second speed-changing state, and a free state, as the actuator 55 translates along the axis of the second spindle 75.

[0033] In the first speed change state, as shown in Fig. 5A, the motor M rotates in a first direction (the direction of arrow D1 in Fig. 5A), and the screw nut 76 (operator 55) moves upward, so that the first engagement element 51 and the second engagement element 52 are connected and the third engagement element 53 and the fourth engagement element 54 are disconnected. In other words, the upper clutch 50U is engaged and the lower clutch 50D is disengaged. In the first speed change state, the power of the motor M is transmitted to the output gear 72, the input gear 77, the operator 55, the first engagement element 51, the second engagement element 52, the first drive gear 78, the first driven gear 79, and the first spindle unit SP1.

[0034] In the second speed change state, as shown in Fig. 5B, the motor M rotates in the second direction (the direction of arrow D2 in Fig. 5B), and the screw nut 76 (operator 55) moves downward, thereby disengaging the first engaging element 51 and the second engaging element 52 and engaging the third engaging element 53 and the fourth engaging element 54. In other words, the upper clutch 50U is disengaged and the lower clutch 50D is engaged. In the second speed change state, the power of the motor M is transmitted to the output gear 72, the input gear 77, the operator 55, the third engaging element 53, the fourth engaging element 54, the second driving gear 80, the second driven gear 81, and the first spindle unit SP1.

[0035] In the free state, as shown in FIG. 5C , the first engaging element 51 and the second engaging element 52 are disengaged, and the third engaging element 53 and the fourth engaging element 54 are disengaged. In other words, the upper clutch 50U is disengaged, and the lower clutch 50D is disengaged. In the free state, the motor M is stopped, and the first driven gear 79 and the second driven gear 81 are rotated by the rotation of the first spindle unit SP1. However, the rotation of the first spindle unit SP1 is transmitted to the first driven gear 79, the first drive gear 78, and the second engaging element 52, but is not transmitted to the first engaging element 51. Similarly, the rotation of the first spindle unit SP1 is transmitted to the second driven gear 81, the second drive gear 80, and the fourth engaging element 54, but is not transmitted to the third engaging element 53.

[0036] 4 to 5C, the symbol D denotes a rotary damper, which applies an appropriate resistance to the second spindle 75 of the second spindle unit SP2 so that the screw nut 76 (operator 55) can reliably move in translation when the motor M rotates. The rotary damper D is composed of a first damper gear 86 provided on the rotation shaft of the rotary damper D, and a second damper gear 87 provided on the second spindle 75 of the second spindle unit SP2 so as to rotate integrally with the second spindle 75 and meshing with the first damper gear 86. The rotary damper D is disposed above and in front of the bottom plate portion 62 of the transmission case 60, and below the motor M.

[0037] With the electric prosthetic leg 1 configured in this way, it is possible to smoothly ascend stairs, whereas with conventional passive prosthetic legs equipped with passive dampers, it was necessary to ascend one step at a time with the non-prosthetic leg.

[0038] Specifically, as shown in Figure 6, when the electric prosthetic leg 1 is extended forward to climb stairs and a load is applied to the electric prosthetic leg 1, a large amount of power is required to extend the knee joint mechanism 30 from a bent position.

[0039] At this time, as shown in Fig. 5A, by rotating the motor M in a first direction (the direction of arrow D1 in Fig. 5A), the power of the motor M is transmitted from the output gear 72 to the input gear 77. By rotating the input gear 77 in a second direction (the direction of arrow D2 in Fig. 5A), the actuator 55 rotates around the second spindle 75 of the second spindle unit SP2 and is guided by the second spindle 75 to move upward. Then, the first engaging element 51 provided above the actuator 55 and the input gear 77 engages with the second engaging element 52 provided below the first drive gear 78, and the interrupting mechanism 50 enters the first speed change state.

[0040] When the interrupter mechanism 50 is in the first speed change state, the power of the motor M is transmitted to the output gear 72, the input gear 77, the actuator 55, the first engagement element 51, the second engagement element 52, the first drive gear 78, the first driven gear 79, and the first spindle unit SP1. The rotation of the first drive gear 78 together with the input gear 77 in the second direction (the direction of arrow D2 in FIG. 5A) causes the first driven gear 79 to rotate in the first direction (the direction of arrow D1 in FIG. 5A), and the rotation of the first driven gear 79 in the first direction (the direction of arrow D1 in FIG. 5A) causes the first spindle 73 of the first spindle unit SP1 to rotate in the first direction (the direction of arrow D1 in FIG. 5A). As a result, the sleeve 74 moves in translation away from the transmission T, and the upper-knee member 20 to which the sleeve 74 is attached rotates around the rotating part 35 relative to the lower-knee member 10 to which the transmission T is attached, thereby extending the knee joint mechanism 30.

[0041] On the other hand, in order to smoothly ascend stairs, it is necessary to bend (lift) the knee joint mechanism 30 from an extended state with weight being applied to the healthy foot, as shown in Figure 7. When bending the knee joint mechanism 30 from an extended state, a large amount of power is not required, but a quick movement is required.

[0042] At this time, as shown in Fig. 5B, by rotating the motor M in the second direction (the direction of arrow D2 in Fig. 5B), the power of the motor M is transmitted from the output gear 72 to the input gear 77. By rotating the input gear 77 in the first direction (the direction of arrow D1 in Fig. 5B), the actuator 55 rotates around the second spindle 75 of the second spindle unit SP2 and is guided by the second spindle 75 to move downward. Then, the third engaging element 53 provided below the actuator 55 and the input gear 77 engages with the fourth engaging element 54 provided above the second drive gear 80, and the interrupting mechanism 50 enters the second speed change state.

[0043] When the interrupter mechanism 50 is in the second speed change state, the power of the motor M is transmitted to the output gear 72, the input gear 77, the actuator 55, the third engagement element 53, the fourth engagement element 54, the second drive gear 80, the second driven gear 81, and the first spindle unit SP1. The rotation of the second drive gear 80 together with the input gear 77 in the first direction (the direction of arrow D1 in FIG. 5B) causes the second driven gear 81 to rotate in the second direction (the direction of arrow D2 in FIG. 5B), and the rotation of the second driven gear 81 in the second direction (the direction of arrow D2 in FIG. 5B) causes the first spindle 73 of the first spindle unit SP1 to rotate in the second direction (the direction of arrow D2 in FIG. 5B). As a result, the sleeve 74 moves in translation so as to approach the transmission T, and the knee-below member 10 to which the transmission T is attached rotates around the rotating part 35 relative to the knee-upper member 20 to which the sleeve 74 is attached, thereby bending the knee joint mechanism 30.

[0044] When descending stairs or walking on flat ground, the power of motor M is not needed and motor M is stopped.

[0045] However, if an external load is applied to the electric prosthetic leg 1 while the motor M is stopped, the knee joint mechanism 30 in its extended state may be unable to withstand the load and may bend, resulting in so-called knee bending. Therefore, the electric prosthetic leg 1 is provided with a damping unit 100 and a damping actuating unit 200 to prevent knee bending when descending stairs, walking on flat ground, etc. Details of the damping unit 100 and the damping actuating unit 200 will be described later.

[0046] In the electric prosthetic leg 1 configured in this manner, the knee joint mechanism 30 can be extended and flexed via a transmission T that transmits the power of the motor M. The rotation range of the knee joint mechanism 30 is limited to 180° or less, and when the knee joint mechanism 30 is extended, the angle formed between the below-knee member 10 and the above-knee member 20 is approximately 180°, and when the knee joint mechanism 30 is flexed, this angle is less than 180°.

[0047] The transmission T has two power transmission paths with different gear ratios, which makes it possible to switch between the extension and flexion movement speeds and the generated power of the knee joint mechanism 30. In particular, when climbing stairs, the required movement speed and generated power differ between when the knee joint mechanism 30 is flexed and when it is extended, and it is possible to change the power transmission path between when the knee joint mechanism 30 is flexed and when it is extended.

[0048] In addition, the interrupting mechanism 50 interposed between the motor M and the transmission T has an upper clutch 50U interposed between the motor M and the first transmission mechanism T1 and a lower clutch 50D interposed between the motor M and the second transmission mechanism T2, so that the two power transmission paths can be appropriately switched.

[0049] In particular, the telescopic device 40 includes a second spindle unit SP2 that converts the rotational power output from the motor M into translational motion of the actuator 55, so that a single motor M can control the actuator 55 and the extension and flexion of the knee joint mechanism 30. Furthermore, the single actuator 55 is configured to be able to switch the transmission T between the first speed-changing state, the second speed-changing state, and a free state, so that simultaneous connection of two power transmission paths can be avoided.

[0050] Furthermore, when the knee joint mechanism 30 is extended and the electric prosthetic leg 1 is viewed along the rotation axis of the rotating unit 35 of the knee joint mechanism 30, the region where the angle between the knee below member 10 and the knee above member 20 is less than 180° (the region behind (the calf) side of the line connecting the rotating unit 35 and the lower swing unit 70 in FIG. 3 ) is called the narrow-angle region, and the region where the angle is 180° or more (the region ahead (the shin) side of the line connecting the rotating unit 35 and the lower swing unit 70 in FIG. 3 ) is called the wide-angle region. The first spindle unit SP1 is disposed in the narrow-angle region. Meanwhile, the motor M is disposed in the wide-angle region. By disposing the first spindle unit SP1 in the narrow-angle region and the motor M in the wide-angle region in this way, the first spindle unit SP1 and the motor M can be disposed in a balanced manner across the rotating unit 35 of the knee joint mechanism 30. Furthermore, the transmission T and the interrupting mechanism 50 are disposed between the motor M and the first spindle unit SP1. Therefore, the motor M, the transmission T, the interrupting mechanism 50, and the first spindle unit SP1 can be disposed together.

[0051] Second Embodiment The electric prosthetic leg 1 of the second embodiment differs from the electric prosthetic leg 1 of the first embodiment in the configuration of the extension device 40. More specifically, in the extension device 40 of the first embodiment, the translational motion of the actuator 55 is realized by converting the rotational power output from the motor M by the second spindle unit SP2. In contrast, in the extension device 40 of the second embodiment, the translational motion of the actuator 55 is realized by a clutch actuator ACT, which is a drive source different from the motor M, and a clutch fork 90 that transmits the power of the clutch actuator ACT to the actuator 55. In the following explanation, the extension device 40 of the electric prosthetic leg 1 of the second embodiment will be explained with reference to Figures 8 and 9, but configurations that are the same as or equivalent to those of the extension device 40 of the electric prosthetic leg 1 of the first embodiment will be assigned the same reference numerals in the figures and explanations will be omitted, and only the differences will be explained.

[0052] As shown in FIGS. 8 and 9 , the extension / contraction device 40 of the second embodiment includes a motor M that outputs rotational power, a transmission T that transmits the power of the motor M, a first spindle unit SP1 that is connected to the transmission T so as to be able to transmit power and that converts the rotational power output from the transmission T into translational motion, a connecting / disconnecting mechanism 50 that is interposed between the motor M and the first and second transmission mechanisms T1 and T2 of the transmission T, a support shaft 95 that is arranged in parallel to the output shaft 71 of the motor M and the first spindle 73 of the first spindle unit SP1 and supports the connecting / disconnecting mechanism 50, a clutch actuator ACT that performs translational motion, and a clutch fork 90 that transmits the power of the clutch actuator ACT to an actuator 55 of the connecting / disconnecting mechanism 50.

[0053] The clutch actuator ACT is a power source different from the motor M, and performs translational motion along the axial direction (vertical direction) of the support shaft 95 as shown by an arrow Y1 in FIG.

[0054] One end of the clutch fork 90 is connected to the clutch actuator ACT, and an intermediate portion is supported by the pivot shaft 65, so that the clutch fork 90 can pivot freely around the pivot shaft 65 as shown by arrow Y2 in Figure 8. At the other end of the clutch fork 90, arms 92 are provided that branch off from a branch portion 91 located on the opposite side of the pivot shaft 65 from the clutch actuator ACT, and extend in opposite arc-shaped directions. A connecting pin 93 that engages with the slide clutch 56, which will be described later, is provided at the tip of each arm 92. Therefore, when the clutch actuator ACT performs translational motion, the clutch fork 90 pivots around the pivot shaft 65, and the connecting pin 93 of the clutch fork 90 pivots up and down.

[0055] The transmission T includes an output gear 72 provided on the output shaft 71 of the motor M, a first input gear 77A and a second input gear 77B provided in the approximate center of the support shaft 95 and meshing with the output gear 72, a first transmission mechanism T1, and a second transmission mechanism T2. The first input gear 77A and the second input gear 77B constitute an input gear 77.

[0056] The first transmission mechanism T1 is composed of a first drive gear 78 that is immovably mounted on the upper side of the support shaft 95, and a first driven gear 79 that is mounted on the first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73 and that meshes with the first drive gear 78.

[0057] The second transmission mechanism T2 is composed of a second drive gear 80 that is immovably mounted on the underside of the support shaft 95, and a second driven gear 81 that is mounted on the first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73 and that meshes with the second drive gear 80.

[0058] The speed ratios of the first and second change gear mechanism T1 and T2 are the same as those in the first embodiment, and therefore will not be described here. The first and second change gear mechanism T1 and T2 are switched by an interrupting mechanism 50. The interrupting mechanism 50 includes an upper clutch 50U interposed between the motor M and the first change gear mechanism T1, a lower clutch 50D interposed between the motor M and the second change gear mechanism T2, and an actuator 55.

[0059] The upper clutch 50U is a dog clutch that includes a first engaging element 51 that is an engaging element on the motor M side and a second engaging element 52 that is an engaging element on the first transmission mechanism T1 side. Explaining in more detail, the first engaging element 51 is provided above the first input gear 77A so as to rotate integrally with the first input gear 77A. The second engaging element 52 is provided below the first drive gear 78 so as to be engageable with the first engaging element 51 and to rotate integrally with the first drive gear 78. The second engaging element 52 and the first drive gear 78 are attached above a support shaft 95 so as to be rotatable relative to the support shaft 95 but not movable therewith.

[0060] The lower clutch 50D is a dog clutch that includes a third engaging element 53 that is an engaging element on the motor M side, and a fourth engaging element 54 that is an engaging element on the second transmission mechanism T2 side. Explaining in more detail, the third engaging element 53 is provided below the second input gear 77B so as to rotate integrally with the second input gear 77B. The fourth engaging element 54 is provided above the second drive gear 80 so as to be engageable with the third engaging element 53 and to rotate integrally with the second drive gear 80. The fourth engaging element 54 and the second drive gear 80 are attached below the support shaft 95 so as to be rotatable but immovable relative to the support shaft 95.

[0061] The actuator 55 includes an annular slide clutch 56 that is constantly engaged with the connecting pin 93 of the clutch fork 90, and a bearing 57 that moves in translation together with the slide clutch 56, and is disposed between the first input gear 77A and the second input gear 77B in the vertical direction.

[0062] The slide clutch 56 is provided with a connecting hole with which the connecting pin 93 of the clutch fork 90 engages, and the connecting hole absorbs the swinging motion of the clutch fork 90 and converts it into vertical translational motion of the slide clutch 56 .

[0063] The bearing 57 comprises an outer ring 57a supported non-rotatably on the slide clutch 56, an inner ring 57b configured to rotate integrally with a first input gear 77A provided with a first engaging element 51 and a second input gear 77B provided with a third engaging element 53, and a rolling element 57c arranged between the outer ring 57a and the inner ring 57b, allowing relative rotation between the outer ring 57a and the inner ring 57b.

[0064] The inner ring 57b is supported on the outer periphery of a support flange 96 that is key-connected to a support shaft 95 together with the first input gear 77A and the second input gear 77B so as to be able to translate up and down.

[0065] The slide clutch 56 and bearing 57 (actuator 55) move upward along the support shaft 95 when one end of the clutch fork 90 moves downward by the clutch actuator ACT, and move downward along the support shaft 95 when one end of the clutch fork 90 moves upward by the clutch actuator ACT. A predetermined gap is provided in the vertical direction between the slide clutch 56 and outer ring 57a and the first input gear 77A, so that the first input gear 77A does not interfere with the slide clutch 56 and outer ring 57a, which are non-rotating members. Similarly, a predetermined gap is provided in the vertical direction between the slide clutch 56 and outer ring 57a and the second input gear 77B, so that the second input gear 77B does not interfere with the slide clutch 56 and outer ring 57a, which are non-rotating members.

[0066] The intermittent mechanism 50 can be in three states: a first speed change state, a second speed change state, and a free state, as the slide clutch 56 and the bearing 57 (operator 55) move in a translational manner in the vertical direction along the axis of the support shaft 95.

[0067] In the first speed change state, the slide clutch 56 and the bearing 57 (operator 55) move upward, so that the first engaging element 51 and the second engaging element 52 are connected and the third engaging element 53 and the fourth engaging element 54 are disconnected, as in Fig. 5A. In other words, the upper clutch 50U is engaged and the lower clutch 50D is disengaged. In the first speed change state, the power of the motor M is transmitted to the output gear 72, the first input gear 77A (the inner ring 57b and the second input gear 77B), the first engaging element 51, the second engaging element 52, the first driving gear 78, the first driven gear 79, and the first spindle unit SP1.

[0068] In the second speed change state, the slide clutch 56 and the bearing 57 (operator 55) move downward, so that the first engaging element 51 and the second engaging element 52 are disengaged and the third engaging element 53 and the fourth engaging element 54 are engaged, as in Fig. 5B. In other words, the upper clutch 50U is disengaged and the lower clutch 50D is engaged. In the second speed change state, the power of the motor M is transmitted to the output gear 72, the second input gear 77B (inner ring 57b and first input gear 77A), the third engaging element 53, the fourth engaging element 54, the second driving gear 80, the second driven gear 81, and the first spindle unit SP1.

[0069] 5C , in the free state, the first engaging element 51 and the second engaging element 52 are disengaged, and the third engaging element 53 and the fourth engaging element 54 are disengaged. In other words, the upper clutch 50U is disengaged, and the lower clutch 50D is disengaged. In the free state, the motor M is stopped, and the first driven gear 79 and the second driven gear 81 are rotated by the rotation of the first spindle unit SP1. However, the rotation of the first spindle unit SP1 is transmitted to the first driven gear 79, the first drive gear 78, and the second engaging element 52, but is not transmitted to the first engaging element 51. Similarly, the rotation of the first spindle unit SP1 is transmitted to the second driven gear 81, the second drive gear 80, and the fourth engaging element 54, but is not transmitted to the third engaging element 53.

[0070] In the electric prosthetic leg 1 configured in this manner, similar to the first embodiment, the knee joint mechanism 30 can be extended and flexed via the transmission T that transmits the power of the motor M, and the effects described for the electric prosthetic leg 1 of the first embodiment can be obtained. Furthermore, in the electric prosthetic leg 1 of the second embodiment, the actuator 55 is switched using a clutch actuator ACT, which is a power source different from the motor M for extending and flexing the knee joint mechanism 30, so the actuator 55 can be switched more stably.

[0071] [Damping section and damping operating section] Next, the damping unit 100 and the damping operating unit 200 provided in the electric prosthetic leg 1 of each embodiment will be described with reference to FIGS. 1 to 4 and 10 to 12. FIG.

[0072] As shown in Figures 3 and 4, the electric prosthetic leg 1 is provided with a damping unit 100 that is connected to a power transmission path that transmits the power of the motor M and is capable of damping the movement of the power transmission path, and a damping operation unit 200 that operates the damping unit 100 at a predetermined timing.

[0073] 3, 4, and 10, the damping unit 100 includes a rotary shaft 102 rotatably supported via a bearing 101 on the top plate 61 of the transmission T and disposed parallel to the first spindle 73, a second gear 104 provided on the outer periphery of the rotary shaft 102 so as to be integrally rotatable therewith and meshing with the first gear 103 which rotates integrally with the first spindle 73, a damper holder 105 provided on the upper end of the rotary shaft 102 so as to be integrally rotatable therewith, a rotary damper 106 including a damper main body 106a held integrally by the damper holder 105 and a rotary shaft 106b protruding upward from the damper main body 106a, and a damping unit 106a fixed to the top plate 61 which accommodates the rotary shaft 102, the first gear 103, the second gear 104, the damper holder 105, and the rotary damper 106. the damping section case 120 (shown only in Figure 4), a first clutch member 107 arranged on the upper surface of the damping section case 120 and connected to the rotary shaft 106b so as to be rotatable together with the rotary shaft 106b, a second clutch member 108 arranged above and facing the first clutch member 107, a plurality of guide pins 109 protruding upward from the damping section case 120 and penetrating a flange portion 108a of the second clutch member 108 to support the second clutch member 108 so as to be movable up and down but not to be rotatable, a plurality of nuts 110 threaded onto the upper end of each guide pin 109 to prevent the second clutch member 108 from coming off, and a plurality of springs 111 arranged on the outer periphery of each guide pin 109 to urge the second clutch member 108 in a direction away from the first clutch member 107.

[0074] The rotary damper 106 applies a predetermined rotational resistance to the relative rotation between the damper body 106a and the rotary shaft 106b. The damper body 106a of the rotary damper 106 is connected to the first spindle 73 via a damper holder 105, the rotary shaft 102, the second gear 104, and the first gear 103, and the rotary shaft 106b of the rotary damper 106 is connected to the damping portion case 120, which is a fixed portion, via a clutch mechanism consisting of a first clutch member 107 and a second clutch member 108.

[0075] In a clutch-disengaged state in which the first clutch member 107 and the second clutch member 108 are separated, the first clutch member 107 rotates freely, so the rotary damper 106 does not operate and the motion of the first spindle 73 is not damped. On the other hand, in a clutch-engaged state in which the second clutch member 108 is pressed downward and the first clutch member 107 and the second clutch member 108 are engaged, the rotation of the first clutch member 107 is restricted, so that the rotational resistance generated between the damper main body 106a and the rotary shaft 106b is transmitted to the first spindle 73 via the damper holder 105, the rotary shaft 102, the second gear 104, and the first gear 103, and the motion of the first spindle 73 is damped.

[0076] Such a damping unit 100 can generate mechanical resistance when the knee joint mechanism 30 extends or bends. Furthermore, because the damping unit 100 is provided so as to be connected to a power transmission path that transmits the power of the motor M, it is possible to enhance the damping function compared to when the damping unit 100 is provided in the knee joint mechanism 30. That is, because the damping function of the rotary damper 106 is proportional to speed, connecting the rotary damper 106 to a power transmission path that rotates at a higher rotational speed than the rotational speed of the knee joint mechanism 30 makes it possible to effectively utilize the damping function of the rotary damper 106.

[0077] Furthermore, in order to more effectively utilize the damping function of the rotary damper 106, it is preferable that the ratio of the rotation speed of the second gear 104 to the rotation speed of the first gear 103 is greater than 1. This makes it possible to connect the rotary damper 106 to the second gear 104, which rotates at a higher rotation speed than the first gear 103, which rotates integrally with the first spindle 73.

[0078] Furthermore, when the rotary damper 106 is provided so as to be connected downstream of the transmission T with the motor M being on the upstream side, as in this embodiment, it is preferable that the transmission T be a speed-increasing mechanism. Conversely, when the rotary damper 106 is provided so as to be connected upstream of the transmission T (on the motor M side), it is preferable that the transmission T be a speed-reducing mechanism.

[0079] The damping section 100 of this embodiment is disposed between the motor M and the first spindle unit SP1, thereby preventing the damping section 100 from protruding outward.

[0080] As shown in Fig. 12, the damping actuating unit 200 mechanically actuates the damping unit 100 by utilizing a moment N generated when the heel H lands during walking. Specifically, as shown in Figs. 1, 2, and 12, the pair of lower sidewalls 13 of the knee below member 10 includes a pair of lower sidewall main bodies 13a extending upward from both the left and right ends of the lower wall portion 12, and a pair of swinging sidewalls 13c connected to the upper and front portions of the lower sidewall main bodies 13a so as to be swingable forward and backward via a swing shaft 13b provided along the left-right direction at the top and front of the lower sidewall main bodies 13a, and connected to the above-knee member 20 via a rotating unit 35. The pair of swinging sidewalls 13c are connected integrally via a connecting wall portion 13d, and integrally include an operating lever 13e (see Fig. 3) located above the second clutch member 108 of the damping unit 100.

[0081] As shown in Figure 11, when walking on flat ground while wearing the electric prosthetic leg 1, the electric prosthetic leg 1 receives a reaction force (compression load) from the ground as an external load from the time when the foot starts to land as shown in Figure 11(A) to the time when the foot finishes to land as shown in Figure 11(D). In particular, at the time when the foot starts to land as shown in Figure 11(A), the reaction force received from the ground increases rapidly, which may cause the knee joint mechanism 30 to bend unintentionally, or so-called knee bending. In the electric prosthetic leg 1 of this embodiment, focusing on the fact that the heel H lands first at the time of starting to land, the swing shaft 13b is arranged in a position spaced forward from the virtual straight line L1 connecting the heel H and the rotating part 35 of the knee joint mechanism 30, as shown in Figure 12.

[0082] With this configuration, when the heel H lands during walking, a moment N is generated around the swing axis 13b, causing the swing side wall 13c to swing relative to the lower side wall main body 13a, and the operating lever 13e presses down on the second clutch member 108 of the damping unit 100, enabling the damping unit 100 to be mechanically operated. This damps the movement of the knee joint mechanism 30, making it possible to suppress unintended bending during landing. Furthermore, since a moment is less likely to be generated at the rotating unit 35 located on the imaginary line L1, unintended bending during landing can be more reliably suppressed.

[0083] 12, the swing axis 13b is located on or near the imaginary line L2 connecting the toe T and the rotating part 35 when the toe T lands. In this way, when the toe T lands, no moment N or only a small moment N is generated and the damping part 100 does not function, so that the state transitions from (D) to (E) in FIG. 11, allowing the knee joint mechanism 30 to smoothly bend when the electric prosthetic leg 1 is swung up.

[0084] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components of the above-described embodiments may be combined in any manner without departing from the spirit of the invention.

[0085] For example, in the above embodiment, an electric prosthetic leg was exemplified as one embodiment of the joint device of the present invention, but this is not limited to this, and it may also be applied to the upper limb (arm joint), to animals other than humans, or to robots.

[0086] Furthermore, in the above embodiment, the power of one motor M is configured to be transmitted to the first transmission mechanism T1 and the second transmission mechanism T2 via the interrupter mechanism 50, but this is not limited to this, and an interrupter mechanism may be provided between each of the two power sources and the first transmission mechanism T1 and the second transmission mechanism T2.

[0087] Furthermore, the on-off mechanism 50 is not limited to a dog clutch, but may be another clutch mechanism such as a friction clutch or a centrifugal clutch, or may be a clutchless mechanism such as a continuous speed ratio change mechanism.

[0088] In addition, in the above embodiment, the damping unit 100 is connected to the first spindle 73, but it may also be connected to the transmission T.

[0089] Furthermore, in the above embodiment, a configuration in which the damping force is generated by the damping unit 100 and the damping actuating unit 200 has been exemplified, but the present invention is not limited to this, and the damping unit 100 may be an electric machine. That is, the damping force may be generated by regeneratively driving the electric machine, or by power driving the electric machine in the reverse direction, i.e., in a direction in which the rotational power due to the external load is reduced, to generate the damping force.

[0090] This specification also describes at least the following: Note that the components in parentheses correspond to those in the above-described embodiment, but are not limited to these.

[0091] (1) a first member (the lower-knee member 10); A second member (above-knee member 20), a connecting portion (knee joint mechanism 30) that connects the first member and the second member so as to change the angle between them; A joint device (electric prosthetic leg 1) including an extension / retraction device (extension device 40) that can change the angle between the first member and the second member by extending and contracting, The telescopic device is A power source (motor M), a power transmission unit that transmits power from the power source, The power transmission unit is A coupling device is provided to be connected to a power transmission path that transmits the power, and includes a damping section (damping section 100) that damps the movement of the power transmission path.

[0092] According to (1), the connecting part can be bent or extended by the power source, and the damping part that damps the movement of the power transmission path can generate resistance when the connecting part is extended or extended.

[0093] (2) The coupling device according to (1), The power source generates rotational power, The power transmission unit further includes a transmission unit (transmission T) that changes the speed of rotation of the power source, The damping portion is provided to be connected to the transmission portion.

[0094] According to (2), since the damping function is proportional to the speed, the damping function can be enhanced by providing it in the speed-changing part that changes the rotation speed of the power source rather than providing it in the connecting part.

[0095] (3) The coupling device according to (2), the transmission unit includes a speed increasing mechanism that increases the rotation speed of the power source, The coupling device is configured so that the damping unit is connected to the power transmission path downstream of the speed change unit when the power source is located upstream.

[0096] According to (3), the damping function is proportional to the speed, so by providing it downstream of the speed increasing mechanism, the damping function can be further improved.

[0097] (4) A coupling device according to any one of (1) to (3), The damping portion is a coupling device disposed between the power source and a member (first spindle 73) that constitutes the power transmission path.

[0098] According to (4), the damping portion can be prevented from protruding outward.

[0099] (5) A coupling device according to any one of (1) to (4), The joint device is a prosthetic leg, The first member is a coupling device having a swing shaft (swing shaft 13b) that is positioned forward and spaced apart from an imaginary line (imaginary line L1) that connects the heel (heel H) and the pivoting part (rotating part 35) of the connection part when the heel lands.

[0100] According to (5), when the heel lands during walking, the moment around the swing axis can be used to mechanically activate the damping unit, which can generate a damping function when a large compressive load acts on the prosthetic leg after the heel lands.

[0101] (6) The coupling device according to (5), The coupling device is configured such that the swing axis is located on or in the vicinity of another imaginary line (imaginary line L2) that connects the toe and the connecting portion when the toe (toe T) lands.

[0102] According to (6), when the toe lands, no moment is generated and the damping section does not function, so the knee can be smoothly flexed when swinging up the prosthetic leg. [Explanation of symbols]

[0103] 1. Electric prosthetic limb 10 Lower knee member (first member) 13b Oscillating shaft 20 Upper knee member (second member) 30 Knee joint mechanism (articulation part) 35 Rotating part 40 Telescopic device 73 First spindle (power transmission part) 100 Attenuation section M Motor (power source) T Transmission (power transmission part) L1 Virtual line L2 Virtual line (another virtual line)

Claims

1. A first member; A second member; a connecting portion that connects the first member and the second member so as to change the angle between the first member and the second member; A joint device including an extension device that can change the angle formed between the first member and the second member by extending and contracting, The telescopic device is A power source and a power transmission unit that transmits power from the power source, The power transmission unit is a power transmission path that transmits the power of the power source; a damping unit that is connected to the power transmission path and that damps the movement of the power transmission path, The power source generates rotational power, the damping unit is a rotary damper that is provided to damp the rotational power transmitted to the power transmission path, includes a damper body and a rotary shaft, and is provided to apply a predetermined rotational resistance to relative rotation between the damper body and the rotary shaft. Coupling device.

2. 2. The coupling device of claim 1, the power transmission unit further includes a speed change unit that is provided on the power transmission path and changes the speed of the rotational power of the power source, The damping portion is provided to be connected to the transmission portion.

3. 3. The coupling device according to claim 2, the transmission unit includes a speed increasing mechanism that increases the rotational power of the power source, The coupling device is configured so that the damping unit is connected to the power transmission path downstream of the speed change unit when the power source is located upstream.

4. The coupling device according to any one of claims 1 to 3, The damping portion is disposed between the power source and a member that constitutes the power transmission path.

5. The coupling device according to any one of claims 1 to 4, The joint device is a prosthetic leg, The first member is provided with a swing shaft that is disposed forward and spaced apart from an imaginary line that connects the heel and the pivoting portion of the connecting portion when the heel lands.

6. 6. The coupling device according to claim 5, The joint device, wherein the swing axis is located on or in the vicinity of another imaginary straight line connecting the toe and the connecting portion when the toe lands.

7. 7. A coupling device according to any one of claims 1 to 6, The power transmission unit further includes a damping operation unit that operates the damping unit at a predetermined timing. Coupling device.

8. A coupling device according to any one of claims 1 to 7, the rotary shaft is connected to a fixed portion via a clutch mechanism including a first clutch member and a second clutch member; In a clutch disengaged state in which the first clutch member and the second clutch member are separated, the rotational power is not attenuated, The rotational power is attenuated in a clutch engagement state in which the first clutch member and the second clutch member are engaged. Coupling device.

9. A coupling device according to claim 8 dependent on claim 7, The joint device is a prosthetic leg, The damping actuation unit includes an actuation lever located above the second clutch member when the prosthetic leg is upright, The operating lever is provided so as to be able to press down the second clutch member when the heel of the prosthetic leg lands and mechanically operate the damping unit. Coupling device.

Images