JP2022133997A - Joint device - Google Patents

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

The present invention relates to a coupling device.

2. Description of the Related Art Conventionally, as a joint device used in a connecting portion that connects two members, there has been known one that includes an expansion device capable of changing the angle formed by the two members. As such a joint device, for example, there is a prosthetic leg used for a knee joint. In Patent Document 1, a sensor is provided in the femoral socket of the prosthetic leg attached to the stump of the amputated leg to detect the contraction movement of the muscle at the stump of the amputated leg, and the resistance to flexion and extension of the knee joint is measured. It is described that the throttling condition of the variable valve of the hydraulic cylinder to be adjusted is controlled based on the detection information from the sensor.

JP-A-11-19105

However, although the prosthetic leg described in Patent Document 1 can generate resistance to flexion or extension, the knee joint portion cannot be flexed or extended.

The present invention provides a joint device capable of bending or extending a joint and generating resistance when the joint is stretched or bent.

The present invention
a first member;
a second member;
a connecting portion that connects the first member and the second member so as to change the angle formed by the first member;
a joint device that can change the angle formed by the first member and the second member by expanding and contracting,
The expansion device is
power source;
a power transmission unit that transmits the power of the power source,
The power transmission unit is
A damping portion is provided so as to be connected to a power transmission path that transmits the power, and damps motion of the power transmission path.

According to the present invention, the connecting portion can be bent or extended by the power source, and resistance can be generated when the connecting portion is extended or bent by the damping portion.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of the electric prosthetic leg 1 of the first embodiment of the present invention as seen obliquely from the front; Fig. 2 is a perspective view of the electric prosthetic leg 1 of Fig. 1 as seen obliquely from behind; 1. It is a figure which shows the internal structure of the electric prosthesis 1 of FIG. 2 is an enlarged view of the power transmission part of the electric prosthetic leg 1 of FIG. 1. FIG. FIG. 5 is a diagram showing power transmission of the power transmission unit of FIG. 4 when the power transmission unit is in the first speed change state; FIG. 5 is a diagram showing power transmission of the power transmission unit when the power transmission unit of FIG. 4 is in a second speed change state; FIG. 5 is a diagram showing power transmission of the power transmission unit when the power transmission unit of FIG. 4 is in a free state; FIG. 10 is a diagram for explaining the power for extending the knee joint mechanism 30 from the bent state when climbing stairs. FIG. 11 is a diagram for explaining the power that bends the knee joint mechanism 30 from the extended state when climbing stairs. Fig. 10 is a perspective view of the power transmission part of the electric prosthetic leg 1 according to the second embodiment of the present invention; FIG. 9 is a cross-sectional view of the power transmission portion of FIG. 8; Fig. 2 is an exploded perspective view of a damping section 100 and a damping action section 200 common to the electric prosthesis 1 of each embodiment of the present invention. (A) to (E) are diagrams showing movements of the electric prosthesis 1 when walking on a flat ground. Fig. 11 is a side view of the electric prosthetic leg 1 in the state of Fig. 11(A);

Hereinafter, each embodiment of an electric prosthetic leg as an example of the joint device of the present invention will be described with reference to the drawings. In the following description, the front-rear direction, the left-right direction, and the up-down direction are defined based on the user of the electric prosthesis. In the drawings, the front of the electric prosthesis is indicated by Fr, the rear by Rr, the left by L, the right by R, the upper by U, and the lower by D.

<First embodiment>
[Electric prosthesis]
As shown in FIGS. 1 to 3, the electric prosthesis 1 of this embodiment is a prosthesis for people without knees. A knee joint mechanism 30 that connects the upper member 20 and the below-the-knee member 10 and the above-knee member 20 so that the angle formed by the above-knee member 20 can be changed, and the angle between the below-the-knee member 10 and the above-the-knee member 20 can be changed by extending and contracting. and a telescopic device 40 .

The upper knee member 20 includes an upper wall portion 22 provided with an adapter 21 connected to a socket (not shown), and a pair of upper side wall portions 23 extending downward from both left and right ends of the upper wall portion 22. It has a substantially U shape with an open bottom when viewed from above.

The below-the-knee side member 10 includes a lower wall portion 12 provided with leg portions 11, and a pair of lower side wall portions 13 extending upward from both left and right ends of the lower wall portion 12. The upper side is open when viewed in the front-rear direction. It has a substantially U-shaped shape.

Between the pair of upper side wall portions 23 of the upper knee member 20, the pair of lower side wall portions 13 of the below-the-knee member 10 are rotatably connected about the rotating portion 35. As shown in FIG. This mechanism connects the below-the-knee member 10 and the above-the-knee member 20 so that the angle formed by the member 20 can be changed, and the knee joint mechanism 30 is configured.

In the space formed between the above-knee member 20 and the below-the-knee member 10, a telescoping device 40 capable of changing the angle formed by the above-the-knee member 10 and the above-the-knee member 20 is provided.

The expansion/contraction device 40 includes a motor M that outputs rotational power and a power transmission section that transmits the power of the motor M, also referring to FIG. 4 . The power transmission unit includes a transmission T, a first spindle unit SP1 that is connected to the transmission T so as to be capable of transmitting power and converts rotational power output from the transmission T into translational motion, a motor M, and a transmission to be described later. The switching mechanism 50 interposed between the first transmission mechanism T1 and the second transmission mechanism T2 of T, and the rotary power output from the motor M are converted into translational motion of the actuator 55 of the switching mechanism 50. and a 2-spindle unit SP2. If power transmission members such as gears are provided on the downstream side of the first spindle unit SP1 as viewed from the motor M, these power transmission members are also included in the power transmission section, and all the power transmission members form the power transmission path. Configure.

The transmission T includes a top plate portion 61, a bottom plate portion 62, and a pair of side plate portions 63 connecting left and right ends of the top plate portion 61 and the bottom plate portion 62, and has a rectangular shape when viewed from the front-rear direction. A transmission case 60 is provided. A pair of rotary wings 64 extending downward from a bottom plate portion 62 of the transmission case 60 can swing around a lower swing portion 70 on a rotation support wall 14 extending upward from the lower wall portion 12 of the below-the-knee side member 10 . and immovably supported.

The motor M is arranged in front of and above the top plate portion 61 of the transmission case 60 so that the output shaft 71 penetrates the top plate portion 61 and protrudes inside the transmission case 60 . The first spindle unit SP1 is arranged on the side opposite to the motor M with the intermittent mechanism 50 interposed therebetween in the front-rear direction. In other words, the motor M is arranged forward of the intermittent mechanism 50 in the longitudinal direction, and the first spindle unit SP1 is arranged rearward of the intermittent mechanism 50 in the longitudinal direction. As a result, even if the electric prosthesis 1 is equipped with the motor M, it is possible to prevent the electric prosthesis 1 from becoming large in the width direction while maintaining balance in the front-rear direction.

The second spindle unit SP2, which converts the rotational power output from the motor M into translational motion of the actuator 55 of the intermittent mechanism 50, is arranged between the motor M and the first spindle unit SP1 in the front-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 arranged in parallel with each other, and when the knee joint mechanism 30 is fully extended, it can move vertically. are placed facing the

The first spindle unit SP1 has a first spindle 73 having a male thread 73a and a sleeve 74 having a female thread 74a. translate along. In this embodiment, the first spindle 73 receives rotational power of the motor M transmitted by the transmission T and performs rotational motion. On the other hand, the sleeve 74 is attached to a pair of inner side wall portions 24 extending downward from the upper wall portion 22 of the upper knee member 20 so as to be able to swing around the upper swing portion 25 and not move. Therefore, when the first spindle 73 rotates to one side (in the direction of arrow D1 in FIG. 5A) by receiving the rotational power of the motor M transmitted by the transmission T, the sleeve 74 is translated away from the transmission T, When the first spindle 73 rotates in the other direction (direction of arrow D2 in FIG. 5B), the sleeve 74 translates closer to the transmission T. As shown in FIG.

That is, the distance between the sleeve 74 and the transmission T expands and contracts according to the rotation direction of the first spindle 73 . Since the sleeve 74 is immovably attached to the upper-knee member 20 as described above, the distance between the sleeve 74 and the transmission T expands and contracts according to the rotation direction of the first spindle 73, so that the transmission T The below-the-knee member 10 to which the sleeve 74 is attached and the above-the-knee member 20 to which the sleeve 74 is attached rotate around the rotating portion 35 . As a result, the angle formed by the upper-knee member 20 and the lower-knee member 10 changes.

As shown in FIG. 4, the transmission T is an output gear 72 provided on the output shaft 71 of the motor M, and an input gear 72 provided substantially in the center of the second spindle 75 of the second spindle unit SP2 and meshing with the output gear 72. A gear 77, a first transmission mechanism T1, and a second transmission mechanism T2 are provided.

The first transmission mechanism T1 includes a first drive gear 78 immovably provided above the second spindle 75 of the second spindle unit SP2, and a first spindle 73 of the first spindle unit SP1 integrated with the first spindle 73. It comprises a first driven gear 79 which is rotatably provided and meshes with a first driving gear 78 .

The second transmission mechanism T2 includes a second driving gear 80 immovably provided under the second spindle 75 of the second spindle unit SP2, and a first spindle 73 on the first spindle 73 of the first spindle unit SP1. It comprises a second driven gear 81 which is provided so as to rotate integrally and meshes with the second driving gear 80 .

The first transmission mechanism T1 transmits the power of the motor M at a first gear ratio. The second transmission mechanism T2 transmits power of the motor M at a second gear ratio different from the first gear ratio. By providing two power transmission paths with different gear ratios, it is possible to switch the operation speed and generated power for extension and flexion in the knee joint mechanism 30 . The first gear ratio and the second gear ratio may be different, and one of the first transmission mechanism T1 and the second transmission mechanism T2 may be a reduction mechanism and the other may be a speed increase mechanism. One may be a constant velocity mechanism and the other may be a reduction mechanism or speed increasing mechanism, both may be reduction mechanisms, or both may be speed increasing mechanisms.

The first gear ratio is a speed change that is the number of revolutions on the opposite side of the motor M (first spindle unit SP1 side) in the first transmission mechanism T1 with respect to the pre-shift number of revolutions that is the number of revolutions on the motor M side in the first transmission mechanism T1. The ratio of the post-rotational speed is defined as the ratio of the rotational speed before shifting, which is the rotational speed of the motor M side in the second transmission mechanism T2. ), the first gear ratio is preferably smaller than the second gear ratio.

For example, when the first transmission gear ratio of the first transmission mechanism T1 is smaller than 1, the rotation speed on the opposite side of the motor M (first spindle unit SP1 side) is lower than the rotation speed on the motor M side, and the torque increases. When the second gear ratio of the second transmission mechanism T2 is greater than 1, the rotation speed on the opposite side of the motor M (first spindle unit SP1 side) increases more than the rotation speed on the motor M side, and the torque decreases. In this case, the first drive gear 78 has a smaller diameter than the second drive gear 80, and the first drive gear 78 and the motor M can be arranged close to each other. In this embodiment, the first transmission mechanism T1 is arranged closer to the motor M than the second transmission mechanism T2. More specifically, the motor M is arranged in front of the first drive gear 78 so as to vertically overlap the first drive gear 78 .

The switching mechanism 50 switches between the first transmission mechanism T1 and the second transmission mechanism T2. The connecting/disconnecting mechanism 50 includes an upper clutch 50U interposed between the motor M and the first transmission mechanism T1, a lower clutch 50D interposed between the motor M and the second transmission mechanism T2, and an input gear. and an actuator 55 that rotates integrally with 77 .

The upper clutch 50U is a dog clutch including 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. More specifically, the first engaging element 51 is provided above the operating element 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 driving gear 78 so as to be able to engage with the first engaging element 51 so as to rotate together with the first driving gear 78 . The second engaging piece 52 and the first drive gear 78 are mounted above the second spindle 75 of the second spindle unit SP2 so as to be relatively rotatable and immovable with respect to the second spindle 75 .

The lower clutch 50D is a dog clutch including 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. More specifically, the third engaging element 53 is provided below the operating element 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 driving gear 80 so as to rotate together with the second driving gear 80 so as to be engageable with the third engaging element 53 . The fourth engaging piece 54 and the second drive gear 80 are attached below the second spindle 75 of the second spindle unit SP2 so as to be relatively rotatable and immovable with respect to the second spindle 75 .

The operating element 55 is attached to the input gear 77 so as to rotate together with the input gear 77 as described above, and the first engaging element 51 and the third engaging element 53 are attached to the upper and lower portions thereof so as to rotate together. ing. The actuator 55 is interposed between the first drive gear 78 and the second drive gear 80 in the approximate center of the second spindle 75, that is, in the vertical direction. Here, the actuator 55 is the screw nut 76 of the second spindle unit SP2. The second spindle unit SP2 has a second spindle 75 with a male thread and a screw nut 76 (actuator 55) with a female thread. The actuator 55) translates while rotating along the axis of the second spindle 75 .

When the motor M rotates in the first direction (arrow D1 direction in FIG. 5A), the screw nut 76 (actuator 55) moves upward in the vertical direction, which is the translational movement direction, and the motor M rotates in the first direction. When rotating in the second direction opposite to the direction (direction of arrow D2 in FIG. 5B), it moves downward in the vertical direction. By changing the rotation direction of the motor M in this manner, the moving direction of the actuator 55 can be changed.

The disconnecting mechanism 50 can take three states of a first speed change state, a second speed change state, and a free state as the operator 55 translates along the axis of the second spindle 75 .

In the first shift state, as shown in FIG. 5A, the motor M rotates in the first direction (the direction of arrow D1 in FIG. 5A), and the screw nut 76 (actuator 55) moves upward. The coupling element 51 and the second engaging element 52 are in the connected state, and the third engaging element 53 and the fourth engaging element 54 are in the disconnected state. In other words, the upper clutch 50U is engaged and the lower clutch 50D is released. In the first speed change state, the power of the motor M is the output gear 72, the input gear 77, the operating element 55, the first engaging element 51, the second engaging element 52, the first driving gear 78, the first driven gear 79, the first It is transmitted to the spindle unit SP1.

In the second speed change state, as shown in FIG. 5B, the motor M rotates in the second direction (arrow D2 direction in FIG. 5B), and the screw nut 76 (actuator 55) moves downward to move the first engagement. The connecting piece 51 and the second engaging piece 52 will be in the disconnected state, and the third engaging piece 53 and the fourth engaging piece 54 will be in the connected state. In other words, the upper clutch 50U is released and the lower clutch 50D is engaged. In the second speed change state, the power of the motor M is the output gear 72, the input gear 77, the operating element 55, the third engaging element 53, the fourth engaging element 54, the second driving gear 80, the second driven gear 81, the first It is transmitted to the spindle unit SP1.

In the free state, as shown in FIG. 5C, the first engaging element 51 and the second engaging element 52 are in the disconnected state, and the third engaging element 53 and the fourth engaging element 54 are in the disconnected state. In other words, the upper clutch 50U is released and the lower clutch 50D is released. In the free state, the motor M stops, and the rotation of the first spindle unit SP1 causes the first driven gear 79 and the second driven gear 81 to rotate. 1 driving gear 78 and the second engaging element 52 , but not 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 not to the third engaging element 53.

In FIGS. 4 to 5C, reference symbol D denotes a rotary damper, and when the motor M rotates, the screw nut 76 (actuator 55) can be reliably translated. provide moderate resistance to The rotary damper D is provided on the second spindle 75 of the second spindle unit SP2 so as to rotate integrally with the first damper gear 86 provided on the rotating shaft of the rotary damper D, and the first damper gear 86. It is composed of a second damper gear 87 and a second damper gear 87 . The rotary damper D is arranged in front of and above the bottom plate portion 62 of the transmission case 60 and below the motor M. As shown in FIG.

With the electric prosthesis 1 configured in this way, it is possible to smoothly perform the step-up operation of the stairs, which has been forced to go up step by step with the non-prosthetic leg side foot in the conventional passive prosthesis equipped with a passive damper.

Specifically, as shown in FIG. 6, when the electric prosthesis 1 is put forward and the electric prosthesis 1 is put forward and a load is applied to the electric prosthesis 1, when the knee joint mechanism 30 is extended from a bent state, a large Power is required.

At this time, as shown in FIG. 5A, the power of the motor M is transmitted from the output gear 72 to the input gear 77 by rotating the motor M in the first direction (arrow D1 direction in FIG. 5A). As the input gear 77 rotates in the second direction (direction of arrow D2 in FIG. 5A), the operating element 55 rotates around the second spindle 75 of the second spindle unit SP2 and is guided upward by the second spindle 75. Moving. Then, the operating element 55 and the first engaging element 51 provided above the input gear 77 are engaged with the second engaging element 52 provided below the first drive gear 78, and the intermittent mechanism 50 is in the first shift state. becomes.

When the intermittent mechanism 50 is in the first speed change state, the power of the motor M is applied to the output gear 72, the input gear 77, the operating element 55, the first engaging element 51, the second engaging element 52, the first driving gear 78, the first driven gear It is transmitted to the gear 79 and the first spindle unit SP1. When the first drive gear 78 rotates together with the input gear 77 in the second direction (direction of arrow D2 in FIG. 5A), the first driven gear 79 rotates in the first direction (direction of arrow D1 in FIG. 5A). The rotation of the driven gear 79 in the first direction (direction of arrow D1 in FIG. 5A) causes the first spindle 73 of the first spindle unit SP1 to rotate in the first direction (direction of arrow D1 in FIG. 5A). As a result, the sleeve 74 is translated away from the transmission T, and the above-the-knee member 20 to which the sleeve 74 is attached rotates around the rotating portion 35 with respect to the below-the-knee member 10 to which the transmission T is attached. Then, the knee joint mechanism 30 extends.

On the other hand, in order to smoothly ascend stairs, it is necessary to bend (lift) the knee joint mechanism 30 from the extended state while a load is applied to the healthy leg, as shown in FIG. When the knee joint mechanism 30 is bent from the extended state, a quick action is required although a large amount of power is not required.

At this time, as shown in FIG. 5B, the power of the motor M is transmitted from the output gear 72 to the input gear 77 by rotating the motor M in the second direction (arrow D2 direction in FIG. 5B). By rotating the input gear 77 in the first direction (arrow D1 direction in FIG. 5B), the actuator 55 rotates around the second spindle 75 of the second spindle unit SP2 and is guided downward by the second spindle 75. Moving. Then, the operating element 55 and the third engaging element 53 provided below the input gear 77 are engaged with the fourth engaging element 54 provided above the second drive gear 80, and the intermittent mechanism 50 enters the second shift state. becomes.

When the intermittent mechanism 50 is in the second speed change state, the power of the motor M is applied to the output gear 72, the input gear 77, the operating element 55, the third engaging element 53, the fourth engaging element 54, the second drive gear 80, the second driven gear It is transmitted to the gear 81 and the first spindle unit SP1. When the second drive gear 80 rotates together with the input gear 77 in the first direction (direction of arrow D1 in FIG. 5B), the second driven gear 81 rotates in the second direction (direction of arrow D2 in FIG. 5B). The rotation of the driven gear 81 in the second direction (direction of arrow D2 in FIG. 5B) causes the first spindle 73 of the first spindle unit SP1 to rotate in the second direction (direction of arrow D2 in FIG. 5B). As a result, the sleeve 74 translates closer to the transmission T, and the lower-knee member 10 to which the transmission T is attached rotates around the rotating portion 35 with respect to the upper-knee member 20 to which the sleeve 74 is attached. Then, the knee joint mechanism 30 bends.

When descending stairs or walking on flat ground, the power of the motor M is not required, so the motor M is stopped.

However, if an external load is applied to the electric prosthetic leg 1 while the motor M is stopped, there is a risk that the knee joint mechanism 30 in the extended state will bend due to the load, which is a so-called knee breakage. Therefore, the electric prosthetic leg 1 is provided with a damping portion 100 and a damping operation portion 200 in order to prevent the knee from bending when descending stairs or walking on a flat surface. Details of the damping section 100 and the damping operation section 200 will be described later.

In the electric prosthetic leg 1 configured in this manner, the knee joint mechanism 30 can be extended and bent via the 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 by the lower knee member 10 and the upper knee member 20 is approximately 180°. When 30 is bent, this angle is less than 180°.

Since the transmission T has two power transmission paths with different gear ratios, it is possible to switch between the extension and flexion operation speeds and generated power in the knee joint mechanism 30 . In particular, when the knee joint mechanism 30 is flexed and extended when climbing stairs, the required operating speed and generated power are different. .

Further, the connecting/disconnecting mechanism 50 interposed between the motor M and the transmission T includes an upper clutch 50U interposed between the motor M and the first transmission mechanism T1, and an upper clutch 50U interposed between the motor M and the second transmission mechanism T2. and the lower clutch 50D interposed between the two power transmission paths can be appropriately switched.

In particular, the extension device 40 includes the second spindle unit SP2 that converts the rotational power output from the motor M into the translational motion of the actuator 55, so that one motor M can control the actuator 55 and the knee joint mechanism 30. control of extension and flexion in the Furthermore, since the transmission T can be switched between the first shift state, the second shift state, and the free state by one actuator 55, it is possible to avoid connecting two power transmission paths at the same time. can.

In addition, when the knee joint mechanism 30 is in an extended state and the electric prosthesis 1 is viewed along the rotation axis of the rotating portion 35 of the knee joint mechanism 30, the angle formed by the below-the-knee member 10 and the above-the-knee member 20 is A region that is less than 180° (a region on the rear (calf) side of the line connecting the rotating portion 35 and the lower swinging portion 70 in FIG. 3) is called a narrow angle region, and the angle formed is 180° or more. If the region (the region on the front (shin) side of the line connecting the rotating portion 35 and the lower swinging portion 70 in FIG. 3) is called a wide-angle region, the first spindle unit SP1 is arranged in the narrow-angle region. . On the other hand, the motor M is arranged in the wide-angle region. By arranging the first spindle unit SP1 in the narrow angle region and the motor M in the wide angle region in this manner, the first spindle unit SP1 and the motor M are balanced across the rotating portion 35 of the knee joint mechanism 30. can be well placed. Furthermore, the transmission T and the switching mechanism 50 are arranged between the motor M and the first spindle unit SP1. Therefore, the motor M, the transmission T, the switching mechanism 50 and the first spindle unit SP1 can be collectively arranged.

<Second embodiment>
The electric prosthesis 1 of the second embodiment differs from the electric prosthesis 1 of the first embodiment in the configuration of the extension device 40 . More specifically, in the expansion device 40 of the first embodiment, the translational motion of the operator 55 is realized by converting the rotational power output from the motor M by the second spindle unit SP2. On the other hand, in the telescopic device 40 of the second embodiment, the translational motion of the actuator 55 is achieved by the clutch actuator ACT, which is a drive source different from the motor M, and the clutch fork that transmits the power of the clutch actuator ACT to the actuator 55 . 90 and . In the following description, the expansion device 40 of the electric prosthesis 1 of the second embodiment will be explained with reference to FIGS. The same reference numerals are used in the drawings to omit the description, and only the points of difference will be described.

As shown in FIGS. 8 and 9, the expansion device 40 of the second embodiment is connected to a motor M that outputs rotational power, a transmission T that transmits the power of the motor M, and the transmission T so that the power can be transmitted. and is interposed between the first spindle unit SP1 that converts the rotational power output from the transmission T into translational motion, and the motor M and the first transmission mechanism T1 and the second transmission mechanism T2 of the transmission T. The connecting/disconnecting mechanism 50, the support shaft 95 arranged in parallel with the output shaft 71 of the motor M and the first spindle 73 of the first spindle unit SP1 and supporting the connecting/disconnecting mechanism 50, the clutch actuator ACT that performs translational movement, and the clutch actuator ACT. and a clutch fork 90 that transmits the power of to the actuator 55 of the disconnecting mechanism 50 .

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 indicated by arrow Y1 in FIG.

One end of the clutch fork 90 is connected to the clutch actuator ACT, and the middle part is supported by the swing shaft 65, thereby swinging the swing shaft 65 as indicated by an arrow Y2 in FIG. It is configured to be swingable at the center. The other end of the clutch fork 90 is provided with an arm 92 bifurcated from a branch portion 91 located on the opposite side of the swing shaft 65 from the clutch actuator ACT and extending arcuately in opposite directions. A connecting pin 93 is provided at the tip of each arm 92 to fit a slide clutch 56, which will be described later. Therefore, when the clutch actuator ACT performs a translational motion, the clutch fork 90 swings about the swing shaft 65, and the connecting pin 93 of the clutch fork 90 swings up and down.

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 substantially in the center of the support shaft 95 and meshing with the output gear 72, a first A transmission mechanism T1 and a second transmission mechanism T2 are provided. The input gear 77 is composed of the first input gear 77A and the second input gear 77B.

The first transmission mechanism T1 includes a first driving gear 78 immovably provided above the support shaft 95, and a first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73, It is composed of a first driven gear 79 that meshes with a first drive gear 78 .

The second transmission mechanism T2 includes a second driving gear 80 immovably provided under the support shaft 95, and a first spindle 73 of the first spindle unit SP1 so as to rotate integrally with the first spindle 73. , and a second driven gear 81 that meshes with the second driving gear 80 .

Note that the gear ratios of the first transmission mechanism T1 and the second transmission mechanism T2 are the same as those in the first embodiment, so description thereof will be omitted here. The switching mechanism 50 switches between the first transmission mechanism T1 and the second transmission mechanism T2. The connecting/disconnecting mechanism 50 includes an upper clutch 50U interposed between the motor M and the first transmission mechanism T1, a lower clutch 50D interposed between the motor M and the second transmission mechanism T2, and an actuator. 55 and .

The upper clutch 50U is a dog clutch including 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. More specifically, the first engaging piece 51 is provided above the first input gear 77A so as to rotate together with the first input gear 77A. The second engaging element 52 is provided below the first driving gear 78 so as to be able to engage with the first engaging element 51 so as to rotate together with the first driving gear 78 . The second engaging piece 52 and the first drive gear 78 are mounted above the support shaft 95 so as to be rotatable relative to the support shaft 95 and immovable.

The lower clutch 50D is a dog clutch including 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. More specifically, the third engaging element 53 is provided below the second input gear 77B so as to rotate together with the second input gear 77B. The fourth engaging element 54 is provided above the second driving gear 80 so as to rotate together with the second driving gear 80 so as to be engageable with the third engaging element 53 . The fourth engaging element 54 and the second driving gear 80 are attached below the support shaft 95 so as to be relatively rotatable and immovable with respect to the support shaft 95 .

The operating element 55 includes an annular slide clutch 56 that is always engaged with the connecting pin 93 of the clutch fork 90, and a bearing 57 that performs translational motion together with the slide clutch 56. It is arranged between the two input gears 77B.

The slide clutch 56 is provided with a connection hole with which the connection pin 93 of the clutch fork 90 is engaged.

The bearing 57 rotates integrally with an outer ring 57a non-rotatably supported by the slide clutch 56, 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 disposed between the outer ring 57a and the inner ring 57b to allow relative rotation between the outer ring 57a and the inner ring 57b.

The inner ring 57b, together with the first input gear 77A and the second input gear 77B, is supported on the outer peripheral portion of a support flange 96 key-connected to the support shaft 95 so as to be vertically translatable.

The slide clutch 56 and the bearing 57 (actuator 55) move upward along the support shaft 95 when one end of the clutch fork 90 is moved downward by the clutch actuator ACT. As one end moves upward, it moves downward along the support shaft 95 . A predetermined gap is provided in the vertical direction between the slide clutch 56 and the outer ring 57a and the first input gear 77A. configured not to interfere. Similarly, a predetermined gap is provided in the vertical direction between the slide clutch 56 and the outer ring 57a and the second input gear 77B. are configured so that they do not interfere.

The connecting/disconnecting mechanism 50 has three states of a first speed change state, a second speed change state, and a free state as a result of the slide clutch 56 and the bearing 57 (actuator 55) vertically translating along the axis of the support shaft 95. can take

In the first shift state, the slide clutch 56 and the bearing 57 (actuator 55) move upward, so that the first engagement element 51 and the second engagement element 52 are connected and the third The engaging element 53 and the fourth engaging element 54 are in the disconnected state. In other words, the upper clutch 50U is engaged and the lower clutch 50D is released. In the first speed change state, the power of the motor M is 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 drive gear 78, It is transmitted to the first driven gear 79 and the first spindle unit SP1.

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

In the free state, as in FIG. 5C, the first engaging element 51 and the second engaging element 52 are in the disconnected state, and the third engaging element 53 and the fourth engaging element 54 are in the disconnected state. In other words, the upper clutch 50U is released and the lower clutch 50D is released. In the free state, the motor M stops, and the rotation of the first spindle unit SP1 causes the first driven gear 79 and the second driven gear 81 to rotate. 1 driving gear 78 and the second engaging element 52 , but not 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 not to the third engaging element 53.

In the electric prosthesis 1 configured in this manner, the knee joint mechanism 30 can be extended and flexed via the transmission T that transmits the power of the motor M, as in the first embodiment. The effects described in the electric prosthesis 1 can be obtained. Further, in the electric prosthesis 1 of the second embodiment, the actuator 55 is switched using the clutch actuator ACT, which is a power source different from the motor M for extending and bending the knee joint mechanism 30, so that the actuator 55 can be switched more stably. The actuator 55 can be switched.

[Attenuation part and attenuation operation part]
Next, the damping section 100 and the damping operation section 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.

As shown in FIGS. 3 and 4, the electric prosthetic leg 1 includes a damping section 100 connected to a power transmission path that transmits the power of the motor M and capable of damping the motion of the power transmission path. and a damping operation unit 200 that operates the unit 100 at a predetermined timing.

As shown in FIGS. 3, 4 and 10, the damping portion 100 is rotatably supported by the top plate portion 61 of the transmission T via a bearing 101, and is arranged parallel to the first spindle 73. 102, a second gear 104 which is provided rotatably on the outer periphery of the rotating shaft 102 and meshes with the first gear 103 which rotates integrally with the first spindle 73; A rotary damper 106 comprising a damper holder 105, a damper body 106a integrally held by the damper holder 105, and a rotary shaft 106b projecting upward from the damper body 106a, a rotating shaft 102, a first gear 103, a second gear 104, A damper holder 105 and a rotary damper 106 are housed in a damping section case 120 (shown only in FIG. 4) fixed to the top plate section 61, and the damping section case 120 is arranged on the upper surface of the damping section case 120 so as to be rotatable integrally with the rotary shaft 106b. A first clutch member 107 to be connected, a second clutch member 108 provided facing above the first clutch member 107, and a flange portion 108a of the second clutch member 108 projecting upward from the attenuation portion case 120. By penetrating through, a plurality of guide pins 109 that support the second clutch member 108 so as to be vertically movable and non-rotatable, and the upper end of each guide pin 109 are screwed to prevent the second clutch member 108 from coming off. A plurality of nuts 110 and a plurality of springs 111 arranged on the outer periphery of each guide pin 109 and biasing the second clutch member 108 away from the first clutch member 107 are provided.

The rotary damper 106 gives 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 the damper holder 105, the rotating 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 first clutch member. 107 and a second clutch member 108, it is connected to a damping portion case 120, which is a fixed portion.

In the clutch disengaged state in which the first clutch member 107 and the second clutch member 108 are separated, the first clutch member 107 idles, so the rotary damper 106 does not operate and the motion of the first spindle 73 is not damped. On the other hand, in the clutch connected 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 with each other, the rotation of the first clutch member 107 is restricted. Rotational resistance generated with the rotary shaft 106b is transmitted to the first spindle 73 via the damper holder 105, the rotating shaft 102, the second gear 104 and the first gear 103, and the motion of the first spindle 73 is damped. be.

Such a damping section 100 can mechanically generate resistance when the knee joint mechanism 30 extends or bends. Moreover, since the damping portion 100 is provided so as to be connected to the power transmission path that transmits the power of the motor M, the damping function can be enhanced compared to when the damping portion 100 is provided in the knee joint mechanism 30 . That is, since the damping function of the rotary damper 106 is proportional to the speed, by connecting the rotary damper 106 to a power transmission path that rotates at a higher rotational speed than the knee joint mechanism 30, the damping of the rotary damper 106 can be reduced. Functions can be used effectively.

Also, in order to effectively utilize the damping function of the rotary damper 106, it is preferable that the ratio of the number of rotations of the second gear 104 to the number of rotations of the first gear 103 is greater than one. As a result, the rotary damper 106 can be connected to the second gear 104 that rotates at a higher rotational speed than the first gear 103 that rotates integrally with the first spindle 73 .

Further, when the motor M is upstream and the rotary damper 106 is connected downstream of the transmission T as in the present embodiment, the transmission T is preferably a speed increasing mechanism. Conversely, when the motor M is on the upstream side and the rotary damper 106 is provided upstream of the transmission T (on the side of the motor M), the transmission T is preferably a speed reduction mechanism.

The attenuation section 100 of this embodiment is arranged between the motor M and the first spindle unit SP1. Accordingly, it is possible to prevent the damping portion 100 from protruding to the outside.

As shown in FIG. 12, the damping operation part 200 mechanically actuates the damping part 100 by utilizing the moment N generated when the heel H lands on the ground during walking. Specifically, as shown in FIGS. 1, 2 and 12, the pair of lower side wall portions 13 of the below-the-knee side member 10 extend upward from the left and right ends of the lower wall portion 12. The main body 13a is connected to the lower side wall main body 13a via a swing shaft 13b provided along the left-right direction at the upper and front portion of the main body 13a so as to be able to swing back and forth. and a pair of swinging side wall portions 13 c connected to the member 20 . The pair of swinging side wall portions 13c are integrally connected via a connecting wall portion 13d, and integrally operate an operating lever 13e (see FIG. 3) positioned above the second clutch member 108 of the damping portion 100. Prepare.

As shown in FIG. 11, when walking on a flat ground while wearing the electric prosthesis 1, the electric prosthesis 1 is in a state from the start of landing shown in (A) of FIG. 11 to the end of landing shown in (D) of FIG. Until then, it receives a reaction force (compressive load) from the ground as a load from the outside. In particular, at the start of landing shown in (A) of FIG. 11 , the reaction force received from the ground suddenly increases, so that the knee joint mechanism 30 may bend unintentionally, that is, the so-called knee bending may occur. . In the electric prosthesis 1 of this embodiment, focusing on landing from the heel H at the start of landing, as shown in FIG. The swing shaft 13b is arranged at a position spaced forward.

With this arrangement, when the heel H lands on the ground during walking, a moment N is generated around the swing shaft 13b, causing the swing side wall portion 13c to swing relative to the lower side wall portion main body 13a. The lever 13e presses down the second clutch member 108 of the damping section 100, and the damping section 100 can be mechanically operated. As a result, the motion of the knee joint mechanism 30 can be attenuated, and unintended bending at the time of landing can be suppressed. In addition, since a moment is less likely to occur in the rotating portion 35 located on the imaginary straight line L1, unintended bending at the time of landing can be suppressed more reliably.

Further, as shown in FIG. 12, the swing shaft 13b is positioned on or near the imaginary straight line L2 connecting the toe T and the rotating portion 35 when the toe T lands. In this way, when the toe T lands on the ground, no moment N is generated or only a small moment N is generated, and the damping section 100 does not function. , the bending motion of the knee joint mechanism 30 can be performed smoothly when the electric prosthesis 1 is raised.

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 obvious that a person skilled in the art can conceive of various modifications or modifications within the scope described in the claims, and these also belong to the technical scope of the present invention. Understood. Moreover, each component in the above embodiments may be combined arbitrarily without departing from the gist of the invention.

For example, in the above embodiment, an electric prosthetic leg was illustrated as one embodiment of the joint device of the present invention, but the present invention is not limited to this, and may be applied to upper limbs (arm joints), and applied to animals other than humans. may be applied to robots.

In the above embodiment, the power of one motor M is transmitted to the first transmission mechanism T1 and the second transmission mechanism T2 via the intermittent mechanism 50. Disconnecting mechanisms may be provided between the source and the first transmission mechanism T1 and the second transmission mechanism T2, respectively.

Further, the connecting/disconnecting mechanism 50 is not limited to a dog clutch, and may be another clutch mechanism such as a friction clutch or a centrifugal clutch, or may be a clutchless mechanism such as a continuous gear ratio switching mechanism.

Further, although the damping portion 100 is connected to the first spindle 73 in the above embodiment, it may be connected to the transmission T as well.

Further, in the above-described embodiment, the configuration in which the damping force is generated by the damping section 100 and the damping operation section 200 is illustrated, but the damping section 100 may be an electric machine. That is, the damping force may be generated by regeneratively driving the electric machine, or the damping force may be generated by power-running the electric machine in the opposite direction, that is, in the direction in which the rotational power due to the external load is reduced. good.

In addition, at least the following matters are described in this specification. In addition, although the parenthesis shows the components corresponding to the above-described embodiment, the present invention is not limited to this.

(1) a first member (below-the-knee member 10);
a second member (upper 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 formed;
A joint device (electric prosthesis 1) comprising an expansion device (expansion device 40) that can change the angle formed by the first member and the second member by expanding and contracting,
The expansion device is
a power source (motor M);
a power transmission unit that transmits the power of the power source,
The power transmission unit is
A joint device comprising a damping section (damping section 100) provided to be connected to a power transmission path that transmits the power and damping motion of the power transmission path.

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

(2) The joint 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,
A coupling device, wherein the damping section is provided to be connected to the transmission section.

According to (2), since the damping function is proportional to the speed, it is possible to enhance the damping function by providing it in the speed change portion that speeds up the rotation of the power source rather than providing it in the connecting portion.

(3) The joint device according to (2),
The transmission unit includes a speed increasing mechanism that speeds up the rotation of the power source,
A joint device, wherein the damping portion is connected downstream of the speed change portion in the power transmission path when the power source is on the upstream side.

According to (3), since the damping function is proportional to the speed, the damping function can be further enhanced by providing it downstream of the speed increasing mechanism.

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

According to (4), it is possible to prevent the damping portion from protruding to the outside.

(5) The joint device according to any one of (1) to (4),
The joint device is a prosthetic leg,
The first member is spaced forward from a virtual straight line (virtual straight line L1) connecting the heel and the rotating portion (rotating portion 35) of the connecting portion when the heel (heel H) lands. A joint device comprising an arranged pivot shaft (pivot shaft 13b).

According to (5), when the heel lands on the ground during walking, the damping section can be mechanically operated by utilizing the moment about the swing axis. This allows a damping function to occur when the heel strikes the ground and a large compressive load acts on the prosthesis.

(6) The joint device according to (5),
The swing shaft is positioned on or near another imaginary straight line (imaginary straight line L2) connecting the toe and the connecting portion when the toe (toe T) lands.

According to (6), when the toe lands on the ground, no moment is generated and the damping section does not function, so the knee can be smoothly flexed when the prosthetic leg is raised.

1 Electric prosthesis 10 Lower knee side member (first member)
13b Swing shaft 20 Knee upper member (second member)
30 Knee joint mechanism (articulation part)
35 rotating part 40 expansion device 73 first spindle (power transmission part)
100 attenuation unit M motor (power source)
T transmission (power transmission part)
L1 virtual straight line L2 virtual straight line (other virtual straight line)

Claims (6)

a first member;
a second member;
a connecting portion that connects the first member and the second member so as to change the angle formed by the first member;
a joint device that can change the angle formed by the first member and the second member by expanding and contracting,
The expansion device is
power source;
a power transmission unit that transmits the power of the power source,
The power transmission unit is
A joint device comprising a damping section provided to be connected to a power transmission path that transmits the power and damping motion of the power transmission path. The coupling device according to claim 1,
The power source generates rotational power,
The power transmission unit further includes a speed change unit that speeds rotation of the power source,
A coupling device, wherein the damping section is provided to be connected to the transmission section. A coupling device according to claim 2,
The transmission unit includes a speed increasing mechanism that speeds up the rotation of the power source,
A joint device, wherein the damping portion is connected downstream of the speed change portion in the power transmission path when the power source is on the upstream side. The joint device according to any one of claims 1 to 3,
The joint device, wherein the damping portion is arranged between the power source and a member forming the power transmission path. The joint device according to any one of claims 1 to 4,
The joint device is a prosthetic leg,
The joint device, wherein the first member includes a swing shaft that is spaced forward from an imaginary straight line that connects the heel and the rotating portion of the connecting portion when the heel lands on the ground. A coupling device according to claim 5,
The joint device, wherein the swing axis is positioned on or in the vicinity of another imaginary straight line connecting the toe and the connecting portion when the toe lands.

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