JP2022117699A - walking aid - Google Patents

Abstract

To provide a walking assist device that can perform a movement matched with a difference in a walking motion of a user.SOLUTION: A walking assist device includes: a support member 2 attached to the thigh of a user; a lower thigh member 3 connected to the support member 2 so as to be rotatable in a bending direction and an extending direction; a hydraulic cylinder 7 provided between the support member 2 and the lower thigh member 3, which contracts when the lower thigh member 3 rotates in the bending direction with respect to the support member 2; and a switch valve 110 having a first housing 111 and a spool 121 moving in an inner periphery of the first housing 111 for switching the flow of working fluid of the hydraulic cylinder 7 according to a position of the spool 121 with respect to the first housing 111. The switch valve 110 has a blocking position 110a for blocking the flow of the working fluid when the hydraulic cylinder 7 is to contract, and throttle positions 110b, 110c, and 110d for throttling the flow rate of the working fluid when the hydraulic cylinder 7 contracts.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a walking assistance device that assists the walking motion of a user.

Patent Literature 1 discloses a knee joint that includes an input cylinder arranged at the sole position of the foot and an output cylinder arranged between the thigh side link and the crus side link. In this knee joint, when the input cylinder is compressed by the floor reaction force during walking, the output cylinder generates extension torque in the thigh side link.

JP 2013-233421 A

By the way, the movement of the user's knee joint during walking differs depending on the difference in walking speed and stride length. However, in the knee joint of Patent Document 1, during the stance phase when the user's foot touches the ground and the weight is applied during walking, the input cylinder is compressed due to the user's foot contacting the ground, and the output The extension of the cylinder in the direction of extending the knee joint prevents the knee from bending. Therefore, the knee cannot be bent while the sole of the foot is in contact with the ground from the heel contact to the toe release, or from the toe contact to the heel release. That is, it is difficult to change the motion according to the difference in walking motion of the user.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a walking assistance device capable of moving in accordance with different walking motions of the user.

The present invention provides a support member attached to the thigh of a user, a crus member connected to the support member so as to be rotatable in a bending direction and an extension direction, and provided between the support member and the crus member. , a first hydraulic cylinder that contracts when the lower leg member rotates in the bending direction with respect to the support member; a switching valve for switching the flow of liquid in the hydraulic cylinder, the switching valve being in a blocking position for blocking the flow of liquid when the first hydraulic cylinder is about to contract, and in a blocking position for blocking the flow of liquid when the first hydraulic cylinder is contracted. and a throttling position for throttling the flow rate of the liquid.

In this invention, when the switching valve is switched to the blocking position, the liquid flow is blocked when the first hydraulic cylinder is about to contract. Therefore, the lower leg member cannot rotate in the bending direction with respect to the support member. On the other hand, when the switching valve is switched to the throttle position, the flow rate of the liquid when the first hydraulic cylinder is about to contract is throttled. Therefore, the lower leg member gently rotates in the bending direction with respect to the support member. In this way, by switching the switching valve between the shut-off position and the narrowed position, it is possible to perform movements in accordance with the different movements of the user's knee joints due to differences in walking speed and stride length.

Further, the present invention includes a foot member connected to the lower leg member so as to be rotatable in the plantar flexion direction and the dorsiflexion direction; A second hydraulic cylinder that contracts when rotated in the dorsiflexion direction, one side pressure chamber that discharges liquid when the first hydraulic cylinder contracts, and one side that discharges liquid when the second hydraulic cylinder contracts. A first communication passage communicating with the side pressure chamber, the other side pressure chamber to which the liquid is supplied when the first hydraulic cylinder contracts, and the other side to which the liquid is supplied when the second hydraulic cylinder contracts. a second communication passage communicating with the pressure chamber; and a third communication passage communicating the second communication passage and the first communication passage. It switches the flow of liquid flowing from the passage to the second communication passage.

In this invention, when the user walks forward, when the bottom of the foot member stepping forward touches the ground, the ankle joint is rotated in the direction of plantar flexion and the knee joint is slightly bent. . When the user moves forward further, the ankle joint rotates in the dorsiflexion direction and the knee joint rotates in the extension direction. At this time, if the switching valve is switched to the shut-off position, the liquid discharged from the second hydraulic cylinder will flow through the first communication passage to the first liquid as the second hydraulic cylinder gradually contracts. Moving to the pressure cylinder gradually extends the first hydraulic cylinder. Therefore, the first hydraulic cylinder and the second hydraulic cylinder can cause the knee joint and the ankle joint to move in accordance with the user's walking motion.

Further, in the present invention, the throttling position has a plurality of throttling positions with mutually different throttling amounts of the liquid.

In the present invention, for example, when the user descends stairs, the ankle joint portion is required to rotate in the dorsiflexion direction and the knee joint portion rotates in the flexion direction. In such a case, the switching valve has a plurality of throttle positions with different throttle amounts, so that the liquid discharged from the one-side pressure chamber of the first hydraulic cylinder can be pumped with a different throttle amount than when walking on flat ground. It can be supplied to the other side pressure chamber of the first hydraulic cylinder. Therefore, the user can take natural walking motions using the walking assistance device not only when walking on flat ground but also when going up and down stairs.

Further, in the present invention, the switching valve is a check valve that allows the flow of liquid when at least one of the first hydraulic cylinder and the second hydraulic cylinder expands and blocks the flow of liquid when it contracts. further has

In this invention, the first hydraulic cylinder can be extended regardless of the state of the second hydraulic cylinder by providing the check valve. Therefore, the movement of extending the knee joint can be performed quickly regardless of the movement of the ankle joint.

Also, in the present invention, the check valve is provided in the spool.

In the present invention, by providing the check valve in the spool, it is possible to reduce the size and weight of the walking assistance device.

Further, the present invention includes a first biasing member that biases the support member so as to rotate with respect to the lower leg member in the extension direction, and a foot member that rotates with respect to the lower leg member in the plantar flexion direction. and a second biasing member for biasing.

In this invention, the first biasing member biases the support member with respect to the crus member in the extension direction, and the second biasing member biases the leg member with respect to the crus member in the plantar flexion direction. The knee and ankle joints can be returned to their natural state during the leg phase (when the foot is off the ground).

Further, in the present invention, the switching valve is attached to the first hydraulic cylinder so that the expansion and contraction direction of the first hydraulic cylinder is the longitudinal direction.

In this invention, since the longitudinal direction of the switching valve coincides with the direction of expansion and contraction of the first hydraulic cylinder, the switching valve is provided along the first hydraulic cylinder and does not protrude greatly from the first hydraulic cylinder. can be prevented.

Further, the present invention further includes a pressure accumulator attached to the first hydraulic cylinder and storing liquid when at least one of the first hydraulic cylinder and the second hydraulic cylinder contracts, and the switching valve The accumulator is provided at the front or rear of the first hydraulic cylinder, and the pressure accumulator is provided at a position opposite to the switching valve across the first hydraulic cylinder.

In this invention, the switching valve and the pressure accumulator are provided in front and behind the first hydraulic cylinder. Accordingly, it is possible to prevent the switching valve and the pressure accumulator from interfering with the bending and extending motions of the knee joint. Moreover, the switching valve and the pressure accumulator are provided along the first hydraulic cylinder, and can be formed in the same shape as the leg of an able-bodied person.

ADVANTAGE OF THE INVENTION According to this invention, the walking assistance apparatus which can move according to the difference in a user's walking motion can be provided.

FIG. 1 is a right side view of the walking assistance device according to the embodiment of the present invention. 2 is a front view in FIG. 1. FIG. 3 is a rear view in FIG. 1. FIG. FIG. 4 is a diagram showing a state in which the lower leg member is rotated in the bending direction and the leg member is rotated in the dorsiflexion direction in FIG. 5 is a diagram showing a state in which a length adjusting member is inserted into the walking assistance device of FIG. 1. FIG. FIG. 6 is a hydraulic circuit of the walking assistance device according to the embodiment of the present invention. FIG. 7 is a cross-sectional view of the switching valve showing a state in which the spool is in the shutoff position. FIG. 8 is a cross-sectional view of the switching valve, showing a state where the spool is in the throttle position. FIG. 9 is a cross-sectional view of the switching valve showing a state in which the spool is in another throttle position. FIG. 10 is a cross-sectional view of the switching valve showing a state in which the spool is in another throttle position. FIG. 11 is a cross-sectional view of the pressure accumulator.

A hydraulic prosthesis (hydraulic prosthesis) 1 as a walking assistance device according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 11 . The hydraulic prosthesis 1 uses hydraulic oil as the liquid. Any other liquid such as hydraulic water may be used instead of the hydraulic oil, as long as it is an incompressible fluid.

Below, the direction in which the lower leg is bent with respect to the thigh (the direction in which the calf is brought closer to the thigh) is referred to as the “bending direction”, and the direction in which the lower leg is extended with respect to the thigh (the direction in which the calf is The direction away from the part) is called the "stretching direction". In addition, the direction in which the foot is bent with respect to the lower leg (the direction in which the toes are brought closer to the lower leg) is called the "dorsiflexion direction", and the direction in which the foot is extended with respect to the lower leg (the toe is moved from the lower leg). away direction) is referred to as the "plantar flexion direction". Also, the time when the foot touches the ground is called the "stance phase", and the time when the foot is off the ground is called the "swing phase".

First, the overall configuration of the hydraulic prosthesis 1 will be described with reference to FIGS. 1 to 5. FIG.

FIG. 1 is a right side view of the hydraulic prosthesis 1. FIG. 2 is a front view in FIG. 1. FIG. 3 is a rear view in FIG. 1. FIG. FIG. 4 is a diagram showing a state in which the lower leg member 3 is rotated in the bending direction and the leg member 4 is rotated in the dorsiflexion direction in FIG. FIG. 5 is a diagram showing a state in which the length adjusting member 33a is inserted into the hydraulic prosthesis 1 of FIG.

As shown in FIGS. 1 to 3, the hydraulic prosthesis 1 is a femoral prosthesis used by a femoral amputee who has amputated the femur. The hydraulic prosthesis 1 includes a support member 2, a lower leg member 3, a foot member 4, a knee joint 5, an ankle joint 6, a hydraulic cylinder 7 as a first hydraulic cylinder, and a hydraulic cylinder 7 as a second hydraulic cylinder. a hydraulic cylinder 8, a coil spring 9 as a first biasing member, a coil spring 10 as a second biasing member, a hydraulic circuit 100 (see FIG. 6) as a hydraulic circuit, a switching valve 110, and an accumulator 140 as a pressure accumulator.

The support member 2 is attached to the user's thigh to support the thigh. A socket (not shown) is attached to the upper portion of the support member 2 to attach the stump (cut point) of the user's thigh. The support member 2 has a cylinder attachment portion 21 to which a tip portion 72a (see FIG. 3) of a rod 72 (described later) of the hydraulic cylinder 7 is rotatably attached. The cylinder attachment portion 21 is provided near the rear end portion of the support member 2 .

The support member 2 has a rotation restricting portion 22 that contacts a rotation restricting portion 34a of the lower leg member 3, which will be described later. The rotation restricting portion 22 is provided near the front end portion of the support member 2 . The rotation restricting portion 22 restricts the rotation of the lower leg member 3 in the extension direction when coming into contact with the rotation restricting portion 34a of the lower leg member 3 (state shown in FIG. 1).

The lower leg member 3 is connected to the support member 2 so as to be rotatable in the bending direction and the extending direction. The lower leg member 3 includes a first frame 31 that supports a cylinder portion 71 (one end) of the hydraulic cylinder 7 described later, and a second frame that supports a cylinder portion 81 (one end) of the hydraulic cylinder 8 described later. 32 and a length adjusting mechanism 33 provided between the first frame 31 and the second frame 32 .

The first frame 31 is connected to the support member 2 via a pivot shaft 51 . The first frame 31 rotates about the rotation shaft 51 with respect to the support member 2 (see FIG. 4). The first frame 31 has a pair of side members 34 and a lower end member 35 connecting the lower ends of the side members 34 to each other.

The side member 34 receives the user's weight input through the support member 2 . A hydraulic cylinder 7 is provided between the pair of side members 34 . A cylinder support shaft 38 is inserted between the pair of side members 34 . A cylinder portion 71 of the hydraulic cylinder 7 is rotatably connected to the cylinder support shaft 38 .

The lower end member 35 supports the pair of side members 34 from below. The lower end member 35 vertically faces an upper end member 37 of the second frame 32, which will be described later. An upper end portion 33 b of the length adjusting mechanism 33 is connected to the lower end member 35 .

The second frame 32 is connected to the lower portion of the first frame 31 via a length adjusting mechanism 33 . The second frame 32 has a pair of side members 36 and an upper end member 37 connecting upper ends of the side members 36 to each other.

The side member 36 supports the upper end member 37 from below. The side members 36 receive the user's weight input through the top member 37 . A hydraulic cylinder 8 is provided between the pair of side members 36 . A cylinder support shaft 39 is inserted between the pair of side members 36 . A cylinder portion 81 of the hydraulic cylinder 8 is rotatably connected to the cylinder support shaft 39 .

The side member 36 has a rotation restricting portion 36a that abuts on a rotation restricting portion 41 of the leg member 4, which will be described later, and a rotation restricting portion 36b that abuts on a rotation restricting portion 42, which will be described later, of the leg member 4. .

The upper end member 37 vertically faces the lower end member 35 of the first frame 31 . A lower end portion 33 c of the length adjusting mechanism 33 is connected to the upper end member 37 .

The length adjusting mechanism 33 has a length adjusting member 33a (see FIG. 5). In the length adjusting mechanism 33, the length adjusting member 33a can be replaced with one having a different length. Thereby, the length of the user's left and right legs can be matched by adjusting the length of the length adjusting member 33a according to the length of the leg on the opposite side of the user.

The first frame 31 that supports the cylinder portion 71 of the hydraulic cylinder 7 and the second frame 32 that supports the cylinder portion 81 of the hydraulic cylinder 8 are provided separately with the length adjusting member 33a interposed therebetween. Therefore, by adjusting the length adjusting member 33a, only the length of the leg member 3 can be changed without changing the sizes of the hydraulic cylinders 7 and 8. FIG.

The leg member 4 is connected to the lower leg member 3 so as to be rotatable in the plantar flexion direction and the dorsiflexion direction. The leg member 4 is connected to the lower leg member 3 via a pivot shaft 61 . The leg member 4 rotates about the rotation shaft 61 with respect to the lower leg member 3 (see FIG. 4).

The foot member 4 is formed in a shape similar to that of a healthy person's foot so that shoes or the like can be worn. The leg member 4 has a cylinder mounting portion 43 to which a tip portion 82a (see FIG. 1) of a rod 82 (described later) of the hydraulic cylinder 8 is rotatably mounted. The cylinder mounting portion 43 is provided in front of a position where the leg member 4 is connected to the lower leg member 3 via the rotation shaft 61 .

The leg member 4 has a rotation restricting portion 41 that contacts the rotation restricting portion 36 a of the lower leg member 3 and a rotation restricting portion 42 that contacts the rotation restricting portion 36 b of the lower leg member 3 . The rotation restricting portion 41 is provided in front of the lower leg member 3 . The rotation restricting portion 41 restricts the rotation of the leg member 4 in the dorsiflexion direction when coming into contact with the rotation restricting portion 36 a of the lower leg member 3 . The rotation restricting portion 42 is provided behind the lower leg member 3 . The rotation restricting portion 42 restricts the rotation of the leg member 4 in the plantar flexion direction when it comes into contact with the rotation restricting portion 36 b of the lower leg member 3 .

The knee joint part 5 has a rotation shaft 51 . The rotating shaft 51 connects the support member 2 and the leg member 3 so as to be rotatable in the bending direction and the extending direction.

The ankle joint part 6 has a rotation shaft 61 . The rotating shaft 61 connects the lower leg member 3 and the leg member 4 so as to be rotatable in the plantar flexion direction and the dorsiflexion direction.

A hydraulic cylinder 7 is provided between the support member 2 and the leg member 3 . When the hydraulic cylinder 7 contracts, the leg member 3 rotates in the bending direction with respect to the support member 2 . When the hydraulic cylinder 7 extends, the lower leg member 3 rotates in the extension direction with respect to the support member 2 . The hydraulic cylinder 7 has a cylinder portion 71 and a rod 72 .

The cylinder portion 71 is provided between the pair of side members 34 . The cylinder portion 71 will be described later in detail with reference to the hydraulic circuit 100 of FIG.

The rod 72 advances and retreats with respect to the cylinder portion 71 . When the rod 72 is withdrawn from the cylinder portion 71, the hydraulic cylinder 7 is extended. On the other hand, when the rod 72 enters the cylinder portion 71, the hydraulic cylinder 7 contracts.

A switching valve 110 and an accumulator 140 are attached to the hydraulic cylinder 7 . Switching valve 110 and accumulator 140 are provided integrally with hydraulic cylinder 7 . Alternatively, the switching valve 110 and the accumulator 140 may be attached to the hydraulic cylinder 8 .

The switching valve 110 is attached to the hydraulic cylinder 7 so that the extension/contraction direction of the hydraulic cylinder 7 is the longitudinal direction. Since the longitudinal direction of the switching valve 110 coincides with the expansion and contraction direction of the hydraulic cylinder 7 , the switching valve 110 is provided along the hydraulic cylinder 7 and can be prevented from protruding greatly from the hydraulic cylinder 7 .

The accumulator 140 stores working oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 contracts.

The switching valve 110 is provided in front of the hydraulic cylinder 7 and the accumulator 140 is provided behind the hydraulic cylinder 7 . Alternatively, the switching valve 110 may be provided behind the hydraulic cylinder 7 and the accumulator 140 may be provided in front of the hydraulic cylinder 7 . That is, the switching valve 110 is provided in front or behind the hydraulic cylinder 7 , and the accumulator 140 is provided in a position opposite to the switching valve 110 with the hydraulic cylinder 7 interposed therebetween. Accordingly, it is possible to prevent the switching valve 110 and the accumulator 140 from interfering with the bending and extending motions of the knee joint portion 5 . Moreover, the switching valve 110 and the accumulator 140 are provided along the hydraulic cylinder 7, and can be formed in the same shape as the leg of an able-bodied person.

The specific configurations of switching valve 110 and accumulator 140 will be described later in detail with reference to FIGS. 7 to 11. FIG.

A hydraulic cylinder 8 is provided between the lower leg member 3 and the leg member 4 . The hydraulic cylinder 8 contracts when the leg member 4 rotates in the dorsiflexion direction with respect to the lower leg member 3 . The hydraulic cylinder 8 extends when the leg member 4 rotates in the plantar flexion direction with respect to the lower leg member 3 . The hydraulic cylinder 8 has a cylinder portion 81 and a rod 82 .

The cylinder portion 81 is provided between the pair of side members 36 . The cylinder portion 81 will be described in detail later with reference to the hydraulic circuit 100 of FIG.

The rod 82 advances and retreats with respect to the cylinder portion 81 . When the rod 82 is withdrawn from the cylinder portion 81, the hydraulic cylinder 8 is extended. On the other hand, when the rod 82 enters the cylinder portion 81, the hydraulic cylinder 8 contracts.

The hydraulic cylinder 8 has a shorter overall length than the hydraulic cylinder 7 . As a result, the hydraulic cylinder 8 can be accommodated in the ankle joint portion 6 having a smaller space than the accommodating portion for the hydraulic cylinder 7 . By changing the diameters of the cylinder portions 71 and 81, the hydraulic cylinders 7 and 8 can be set according to the user's walking motion.

A coil spring 9 is provided on the outer circumference of the rod 72 . The coil spring 9 biases the support member 2 so as to rotate relative to the lower leg member 3 in the extension direction. When the rod 72 withdraws from the cylinder portion 71, the coil spring 9 extends along with the extension of the rod 72. On the other hand, when the rod 72 enters the cylinder portion 71 , the coil spring 9 contracts together with the contraction of the rod 72 .

Coil spring 10 is provided on the outer circumference of rod 82 . The coil spring 10 urges the leg member 4 to rotate relative to the lower leg member 3 in the plantar flexion direction. When the rod 82 withdraws from the cylinder portion 81, the coil spring 10 extends together with the extension of the rod 82. As shown in FIG. On the other hand, when the rod 82 enters the cylinder portion 81 , the coil spring 10 contracts together with the contraction of the rod 82 .

The coil spring 9 urges the support member 2 with respect to the crus member 3 in the extension direction, and the coil spring 10 urges the leg member 4 with respect to the crus member 3 in the plantar flexion direction. The joint part 5 and the ankle joint part 6 can be returned to their natural state.

Instead of the coil springs 9 and 10, other springs or the like may be provided as the first biasing member and the second biasing member. Alternatively, the coil springs 9 and 10 may be provided independently from the hydraulic cylinders 7 and 8 instead of the outer circumferences of the rods 72 and 82 .

Next, referring to FIG. 6, the hydraulic circuit 100 of the hydraulic prosthesis 1 will be described. 6 shows the hydraulic circuit 100 of the hydraulic prosthesis 1. FIG.

The hydraulic circuit 100 moves hydraulic oil according to the operation of the hydraulic cylinders 7 and 8 . The hydraulic circuit 100 includes a first communication passage 101 , a second communication passage 102 , a third communication passage 103 , a switching valve 110 and an accumulator 140 .

The hydraulic cylinder 7 has a cylinder portion 71, a rod 72, a piston 73, a piston side chamber 74 as one side pressure chamber, and a rod side chamber 75 as the other side pressure chamber.

The rod 72 is provided integrally with the piston 73 and extends to the outside of the cylinder portion 71 . The piston 73 slides inside the cylinder portion 71 . The piston 73 defines a piston-side chamber 74 and a rod-side chamber 75 within the cylinder portion 71 . The piston-side chamber 74 discharges hydraulic oil when the hydraulic cylinder 7 contracts. Hydraulic oil is supplied to the rod-side chamber 75 when the hydraulic cylinder 7 contracts.

The hydraulic cylinder 8 has a cylinder portion 81, a rod 82, a piston 83, a piston side chamber 84 as one side pressure chamber, and a rod side chamber 85 as the other side pressure chamber.

The rod 82 is provided integrally with the piston 83 and extends to the outside of the cylinder portion 81 . The piston 83 slides inside the cylinder portion 81 . The piston 83 defines a piston-side chamber 84 and a rod-side chamber 85 within the cylinder portion 81 . The piston-side chamber 84 discharges hydraulic oil when the hydraulic cylinder 8 contracts. Hydraulic oil is supplied to the rod side chamber 85 when the hydraulic cylinder 8 contracts.

The first communication path 101 allows the piston side chamber 74 of the hydraulic cylinder 7 and the piston side chamber 84 of the hydraulic cylinder 8 to communicate with each other. The second communication path 102 allows the rod side chamber 75 of the hydraulic cylinder 7 and the rod side chamber 85 of the hydraulic cylinder 8 to communicate with each other.

When the hydraulic cylinder 8 contracts, hydraulic fluid moves from the piston side chamber 84 to the piston side chamber 74 through the first communication passage 101, and hydraulic fluid moves from the rod side chamber 75 to the rod side chamber 85 through the second communication passage 102. As a result, the hydraulic cylinder 7 extends. On the other hand, when the hydraulic cylinder 8 extends, hydraulic fluid moves from the piston side chamber 74 to the piston side chamber 84 through the first communication passage 101, and hydraulic fluid flows from the rod side chamber 85 to the piston side chamber 84 through the second communication passage 102. As it moves, the hydraulic cylinder 7 contracts.

The third communication path 103 allows the second communication path 102 and the first communication path 101 to communicate with each other. The third communication path 103 is provided with a bridge path 108 branched from the third communication path 103 and connected to the third communication path 103 again.

The switching valve 110 is provided in the third communication path 103 and switches the flow of hydraulic oil flowing from the first communication path 101 to the second communication path 102 . The switching valve 110 has a shutoff position 110a and a first throttle position 110b, a second throttle position 110c, and a third throttle position 110d as a plurality of throttle positions. That is, the switching valve 110 has a blocking position 110a that blocks the flow of hydraulic oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 is about to contract, and at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 is contracted. It has throttling positions 110b, 110c, and 110d for throttling the flow rate of the hydraulic oil when it is. A common check valve 130 is provided at the blocking position 110a, the first throttle position 110b, the second throttle position 110c, and the third throttle position 110d.

A check valve 130 is provided in the bridge passage 108 . The check valve 130 blocks the flow of hydraulic oil so that the hydraulic oil does not flow from the first communication path 101 to the second communication path 102, and prevents the hydraulic oil from flowing from the second communication path 102 to the first communication path 101. allow only That is, the check valve 130 allows the flow of hydraulic oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 expands and blocks the flow of hydraulic oil when it contracts.

In the blocking position 110a, the check valve 130 allows the flow for operation from the second communication path 102 to the first communication path 101, and the flow of hydraulic oil from the first communication path 101 to the second communication path 102 is reversed. It is shut off by stop valve 130 .

At the first throttle position 110b, the check valve 130 allows the flow for operation from the second communication path 102 to the first communication path 101, and the hydraulic fluid flows from the first communication path 101 to the second communication path 102. is narrowed down by the first diaphragm 105 .

The first throttle 105 throttles hydraulic oil flowing from the first communication path 101 to the second communication path 102 . That is, the hydraulic oil that has been throttled by the first throttle 105 flows from the first communication path 101 to the second communication path 102 .

At the second throttle position 110c, the check valve 130 permits the working flow from the second communication path 102 to the first communication path 101, and the hydraulic fluid flows from the first communication path 101 to the second communication path 102. is narrowed down by the second diaphragm 106 .

The second throttle 106 throttles hydraulic oil flowing from the first communication path 101 to the second communication path 102 . That is, the hydraulic oil that has been throttled by the second throttle 106 flows from the first communication path 101 to the second communication path 102 . The diaphragm amount of the second diaphragm 106 is smaller than the diaphragm amount of the first diaphragm 105 . Therefore, at the second throttle position 110c, the flow rate of hydraulic oil from the first communication passage 101 to the second communication passage 102 is greater than at the first throttle position 110b.

At the third throttle position 110d, the check valve 130 allows the working flow from the second communication path 102 to the first communication path 101, and the hydraulic oil flows from the first communication path 101 to the second communication path 102. is narrowed down by the third diaphragm 107 .

The third throttle 107 throttles hydraulic oil flowing from the first communication path 101 to the second communication path 102 . That is, hydraulic oil that has been throttled by the third throttle 107 flows from the first communication path 101 to the second communication path 102 . The aperture amount of the third aperture 107 is even smaller than that of the second aperture 106 . Therefore, at the third throttle position 110d, the flow rate of hydraulic oil from the first communication passage 101 to the second communication passage 102 is even greater than at the second throttle position 110c.

The accumulator 140 is provided so as to communicate with the second communication path 102 . The accumulator 140 compensates for changes in the volume of hydraulic fluid in the hydraulic circuit 100 that change according to the lengths of the rods 72 and 82 moving forward and backward with respect to the cylinder portions 71 and 81 . That is, the accumulator 140 stores hydraulic oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 contracts. The accumulator 140 also compensates for changes in hydraulic fluid volume due to temperature changes.

Next, a specific configuration of switching valve 110 will be described with reference to FIGS. 7 to 10. FIG.

FIG. 7 is a cross-sectional view of switching valve 110 showing a state in which spool 121 is at blocking position 110a. FIG. 8 is a cross-sectional view of switching valve 110, showing a state where spool 121 is at first throttle position 110b. FIG. 9 is a cross-sectional view of switching valve 110, showing a state where spool 121 is at second throttle position 110c. FIG. 10 is a cross-sectional view of switching valve 110, showing a state where spool 121 is at third throttle position 110d.

As shown in FIG. 7, the switching valve 110 has a first housing 111 as a main body, a second housing 117, a spool 121, a return spring 118, a wire 119, and a check valve .

The first housing 111 is formed in a cylindrical shape having a spool hole 112 on its inner periphery. The first housing 111 includes a first piston-side port 111a, a first rod-side port 111b, a second piston-side port 111c, a second rod-side port 111d, a spool hole 112, a first connection port 113a, It has a second connection port 113b, a third connection port 113c, a fourth connection port 113d, and a fifth connection port 113e.

The first piston-side port 111 a opens to the outside of the first housing 111 and directly communicates with the piston-side chamber 74 of the hydraulic cylinder 7 . The first rod side port 111b opens to the outside of the first housing 111 and directly communicates with the rod side chamber 75 of the hydraulic cylinder 7 . The second piston-side port 111c opens to the outside of the first housing 111 and communicates with the piston-side chamber 84 of the hydraulic cylinder 8 through an external pipe (not shown). The second rod side port 111d opens to the outside of the first housing 111 and communicates with the rod side chamber 85 of the hydraulic cylinder 8 through an external pipe (not shown).

The spool hole 112 is a through hole whose both ends are open to the end faces of the first housing 111 . A spool 121 is axially movably provided in the spool hole 112 .

The first connection port 113a opens into the spool hole 112 and communicates with the first piston side port 111a via the bridge passage 108 . The second connection port 113b opens into the spool hole 112 and communicates with the first rod side port 111b. The third connection port 113c opens into the spool hole 112 and communicates with the second piston side port 111c. The fourth connection port 113d opens to the spool hole 112 and communicates with the second rod side port 111d. The fifth connection port 113e opens to the spool hole 112 and communicates with the first piston-side port 111a.

The first connection port 113a always communicates with the third connection port 113c through a first annular groove 122a, which will be described later, regardless of the position of the spool 121. As shown in FIG. Therefore, the piston-side chamber 74 of the hydraulic cylinder 7 and the piston-side chamber 84 of the hydraulic cylinder 8 are always in communication. That is, a passage connecting the first connection port 113a, the first annular groove 122a, and the third connection port 113c corresponds to the first communication passage 101. As shown in FIG.

The second connection port 113b always communicates with the fourth connection port 113d via a fifth annular groove 122e, which will be described later, regardless of the position of the spool 121. As shown in FIG. Therefore, the rod-side chamber 75 of the hydraulic cylinder 7 and the rod-side chamber 85 of the hydraulic cylinder 8 are always in communication. That is, the passage connecting the second connection port 113b, the fifth annular groove 122e, and the fourth connection port 113d corresponds to the second communication passage 102. As shown in FIG.

The second housing 117 is formed in a cylindrical shape with a bottom and closes one opening of the first housing 111 . The second housing 117 has a recess 117a into which the spool 121 can enter. A return spring 118 is accommodated in the recess 117a. A wire 119 is inserted through the axial end of the second housing 117 .

The spool 121 is formed in a substantially columnar shape. The spool 121 moves inside the spool hole 112 formed in the first housing 111 . The spool 121 includes a first land portion 121a, a second land portion 121b, a third land portion 121c, a fourth land portion 121d, a fifth land portion 121e, a sixth land portion 121f, and an inner peripheral passage 123. and have The first land portion 121 a , the second land portion 121 b , the third land portion 121 c , the fourth land portion 121 d , the fifth land portion 121 e and the sixth land portion 121 f are in sliding contact with the inner periphery of the spool hole 112 .

A first annular groove 122a is formed between the first land portion 121a and the second land portion 121b. A second annular groove 122b is formed between the second land portion 121b and the third land portion 121c. A third annular groove 122c is formed between the third land portion 121c and the fourth land portion 121d. A fourth annular groove 122d is formed between the fourth land portion 121d and the fifth land portion 121e. A fifth annular groove 122e is formed between the fifth land portion 121e and the sixth land portion 121f.

The inner peripheral passage 123 is axially provided along the central axis of the spool 121 . The inner peripheral passage 123 communicates the first annular groove 122 a and the fifth annular groove 122 e via the check valve 130 . That is, the inner peripheral passage 123 corresponds to the third communication passage 103 .

Also, the spool 121 has a first diaphragm 105 , a second diaphragm 106 and a third diaphragm 107 .

The first throttle 105 allows the second annular groove 122b and the inner peripheral passage 123 to communicate with each other. The second throttle 106 allows the third annular groove 122c and the inner peripheral passage 123 to communicate with each other. The third throttle 107 allows the fourth annular groove 122d and the inner peripheral passage 123 to communicate with each other. The first throttle 105 , the second throttle 106 and the third throttle 107 communicate with the fifth connection port 113 e depending on the position of the spool 121 with respect to the first housing 111 . That is, the switching valve 110 switches the flow of hydraulic oil to the hydraulic cylinder 7 depending on the position of the spool 121 with respect to the first housing 111 .

The first diaphragm 105, the second diaphragm 106, and the third diaphragm 107 are each set to a predetermined diaphragm amount depending on the length of the diaphragm. Alternatively, the first throttle 105, the second throttle 106, and the third throttle 107 may each be set to a predetermined throttle amount by changing the passage area of the throttle. The first diaphragm 105 , the second diaphragm 106 , and the third diaphragm 107 are provided at regular intervals in the axial direction of the spool 121 . The order of the first diaphragm 105, the second diaphragm 106, and the third diaphragm 107 can be arbitrarily changed to an order that is easy for the user to operate. In addition, since a plurality of diaphragms 105, 106, and 107 may be provided, the number of diaphragms may be two, or four or more.

A return spring 118 biases the spool 121 away from the second housing 117 .

The wire 119 is connected to the end of the spool 121 on the second housing 117 side. The wire 119 is operated by the user and pulled out to the outside. The wire 119 is pulled out to the outside by a rotary or direct-acting operation part (not shown) that can adjust the amount of pulling out to the outside in stages. It should be noted that a switching device (not shown) that can pull out the wire 119 to the outside by an electric motor, for example, may be used. In this case, the switching device adjusts the amount of the wire 119 pulled out to the outside step by step based on the switch operation by the user.

As shown in FIG. 7, when the wire 119 is not pulled out, the switching valve 110 is switched to the blocking position 110a.

At this time, the spool 121 does not allow the fifth connection port 113e to communicate with any of the second annular groove 122b, the third annular groove 122c, and the fourth annular groove 122d. That is, hydraulic oil does not flow through any of the first throttle 105, the second throttle 106, and the third throttle 107.

As shown in FIG. 8, when the wire 119 is pulled out by the user, the spool 121 moves and the switching valve 110 is switched to the first throttle position 110b. At this time, the spool 121 allows communication between the fifth connection port 113e and the fourth annular groove 122d. That is, hydraulic oil flows through the first throttle 105 .

As shown in FIG. 9, when the wire 119 is pulled out further by the user, the spool 121 moves further and the switching valve 110 is switched to the second throttle position 110c. At this time, the spool 121 allows communication between the fifth connection port 113e and the third annular groove 122c. That is, hydraulic oil flows through the second throttle 106 .

As shown in FIG. 10, when the wire 119 is further pulled out by the user, the spool 121 moves further and the switching valve 110 is switched to the third throttle position 110d. At this time, the spool 121 allows communication between the fifth connection port 113e and the second annular groove 122b. That is, hydraulic oil flows through the third throttle 107 .

Returning to FIG. 7, the check valve 130 allows the flow of hydraulic fluid when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 expands and blocks the flow of hydraulic fluid when it contracts. A check valve 130 is provided within the spool 121 . By providing the check valve 130 in the spool 121, the size and weight of the hydraulic prosthesis 1 can be reduced. The check valve 130 has a valve seat 131 , a valve body 132 and a compression spring 133 .

A valve seat 131 is provided at the end of the inner peripheral passage 123 . The valve seat 131 is formed so as to expand in diameter from the end of the inner peripheral passage 123 .

The valve body 132 blocks the third communication path 103 while seated on the valve seat 131 . The valve body 132 communicates with the third communication path 103 while being separated from the valve seat 131 .

A compression spring 133 biases the valve body 132 toward the valve seat 131 . When the pressure of the hydraulic fluid in the inner peripheral passage 123 overcomes the biasing force of the push spring 133 , the push spring 133 is compressed and the valve body 132 is separated from the valve seat 131 . This allows hydraulic fluid to flow from the second communication path 102 to the first communication path 101 via the third communication path 103 .

By providing the check valve 130 in this manner, the hydraulic cylinder 7 can be extended regardless of the state of the hydraulic cylinder 8 . Therefore, the movement of extending the knee joint portion 5 can be performed quickly regardless of the movement of the ankle joint portion 6 . Moreover, since the check valve 130 is provided, the hydraulic cylinder 8 can be extended regardless of the state of the hydraulic cylinder 7 . Therefore, regardless of the movement of the knee joint 5, the plantar flexion of the ankle joint 6 can be performed quickly.

Next, a specific configuration of accumulator 140 will be described with reference to FIG. 11 .

The accumulator 140 has a housing 141 , a piston 142 , a compression spring 143 and a rod 144 .

The housing 141 is formed in a cylindrical shape in which the piston 142 can slide on the inner circumference. One end of housing 141 is closed by plug 145 . The housing 141 has a communication passage 141a that communicates with the rod side chamber 75 of the hydraulic cylinder 7 .

The piston 142 moves along the inner periphery of the housing 141 in the central axis direction. The piston 142 forms an accumulator chamber 146 that stores hydraulic oil between the piston 142 and the plug 145 .

A compression spring 143 urges the piston 142 in a direction to approach the plug 145 , that is, in a direction to reduce the volume of the pressure accumulation chamber 146 .

The piston 142 abuts on the top surface 145a of the plug 145 due to the biasing force of the compression spring 143 when hydraulic oil does not flow into the pressure accumulation chamber 146 from the communicating passage 141a. At this time, the piston 142 stops at a height that does not block the communication between the pressure accumulation chamber 146 and the communication passage 141a. When the hydraulic fluid flows into the accumulator chamber 146 , the pressure of the hydraulic fluid overcomes the biasing force of the push spring 143 and the piston 142 moves away from the plug 145 . As a result, the volume of the pressure accumulation chamber 146 is increased, and the hydraulic oil can be stored.

The rod 144 protrudes outside the housing 141 . Rod 144 is fixed to piston 142 and moves with piston 142 . The amount of rod 144 protruding to the outside increases as the amount of hydraulic fluid flowing into pressure accumulating chamber 146 increases. Thereby, the user can confirm how much hydraulic fluid is accumulated in the pressure accumulation chamber 146 based on the amount of protrusion of the rod 144 .

Next, a walking motion using the hydraulic prosthesis 1 will be described.

First, a case where a user wearing the hydraulic prosthesis 1 on one leg walks on a flat ground will be described.

When the user walks forward, the other leg is stepped forward, and then the one leg on which the hydraulic prosthesis 1 is attached is stepped forward. When the bottom of the foot member 4 stepped forward touches the ground, the ankle joint 6 is rotated in the direction of plantar flexion and the knee joint 5 is slightly bent. From this state, when the user moves forward further, the ankle joint portion 6 rotates in the dorsiflexion direction and the knee joint portion 5 rotates in the extension direction.

Here, when the walking speed is slow or the stride length is short, the user switches the switching valve 110 to the blocking position 110a. When the switching valve 110 is switched to the blocking position 110a, the hydraulic oil discharged from the hydraulic cylinder 8 moves to the hydraulic cylinder 7 through the first communication passage 101 as the hydraulic cylinder 8 gradually contracts. . As a result, the hydraulic cylinder 7 is gradually extended.

Thus, when the switching valve 110 is switched to the blocking position 110a, the hydraulic cylinder 7 gradually expands as the hydraulic cylinder 8 gradually contracts. Therefore, the hydraulic cylinders 7 and 8 can cause the knee joint portion 5 and the ankle joint portion 6 to move in accordance with the user's walking motion.

On the other hand, when the walking speed is fast or the stride is long, the user switches the switching valve 110 to the second throttle position 110c or the third throttle position 110d. When the switching valve 110 is switched to the second throttle position 110c or the third throttle position 110d, the hydraulic oil discharged from the piston side chamber 74 of the hydraulic cylinder 7 flows through the second throttle 106 or the third throttle 107 to the rod side chamber 75. can be supplied to Therefore, the ankle joint portion 6 can be rotated in the dorsiflexion direction and the knee joint portion 5 can be rotated in the bending direction.

In this manner, when the user switches the switching valve 110 to the second throttle position 110c or the third throttle position 110d, the flow rate of hydraulic oil is throttled when the hydraulic cylinder 7 is about to contract. Therefore, the leg member 3 gently rotates in the bending direction with respect to the support member 2 . Thus, by switching the switching valve 110 to the second throttle position 110c or the third throttle position 110d, the hydraulic prosthesis 1 can move in accordance with the movement of the knee joint 5 of the user, which varies depending on the difference in walking speed and stride length. can do. Therefore, it is possible to provide the hydraulic prosthesis 1 that can move according to the difference in walking motion of the user.

Next, a case where a user wearing the hydraulic prosthesis 1 on one leg ascends and descends stairs will be described.

When the user ascends the stairs, the user switches the switching valve 110 to the blocking position 110a. When the switching valve 110 is switched to the blocking position 110a, the hydraulic oil discharged from the hydraulic cylinder 8 moves to the hydraulic cylinder 7 through the first communication passage 101 as the hydraulic cylinder 8 gradually contracts. . As a result, the hydraulic cylinder 7 is gradually extended. In addition, the hydraulic prosthesis 1 is stable in an upright state because the knee joint 5 does not rotate in the bending direction without interlocking with the movement of the ankle joint 6 . Therefore, even when climbing stairs, the user can use the hydraulic prosthesis 1 to perform a natural walking motion.

On the other hand, when the user descends the stairs, the user switches the switching valve 110 to the first throttle position 110b. When the switching valve 110 is switched to the first throttle position 110b or the third throttle position 110d, the hydraulic oil discharged from the piston side chamber 74 of the hydraulic cylinder 7 can be supplied to the rod side chamber 75 through the first throttle 105. can. Therefore, the ankle joint portion 6 can be rotated in the dorsiflexion direction and the knee joint portion 5 can be rotated in the bending direction. In addition, in the hydraulic prosthesis 1, the knee joint part 5 slowly rotates in the bending direction without interlocking with the movement of the ankle joint part 6, so the leg on the lower step can be slowly bent. Therefore, even when going down the stairs, the user can use the hydraulic prosthesis 1 to perform a natural walking motion.

In this way, the switching valve 110 has a plurality of throttle positions 110b, 110c, and 110d with different throttle amounts, so that the hydraulic oil discharged from the piston-side chamber 74 of the hydraulic cylinder 7 is distributed to different throttles than when walking on flat ground. , can be supplied to the rod-side chamber 75 of the hydraulic cylinder 7 . Therefore, the user can take natural walking motions using the hydraulic prosthesis 1 not only when walking on flat ground but also when going up and down stairs.

Configurations, functions, and effects of embodiments of the present invention will be collectively described below.

The hydraulic prosthesis 1 includes a support member 2 attached to the user's thigh, a lower leg member 3 connected to the support member 2 so as to be rotatable in the bending direction and the extension direction, and the support member 2 and the lower leg member 3. and has a hydraulic cylinder 7 that contracts when the lower leg member 3 rotates in the bending direction with respect to the support member 2, and a spool 121 that moves along the inner periphery of the first housing 111 and the first housing 111. and a switching valve 110 for switching the flow of hydraulic fluid in the hydraulic cylinder 7 according to the position of the spool 121 with respect to the first housing 111. The switching valve 110 switches the flow of hydraulic fluid when the hydraulic cylinder 7 is about to contract. It has a blocking position 110a for blocking, and throttle positions 110b, 110c, 110d for throttling the flow rate of hydraulic oil when the hydraulic cylinder 7 contracts.

In this configuration, when the switching valve 110 is switched to the blocking position 110a, the flow of hydraulic oil is blocked when the hydraulic cylinder 7 is about to contract. Therefore, the leg member 3 cannot rotate in the bending direction with respect to the support member 2 . On the other hand, when the switching valve 110 is switched to the throttle positions 110b, 110c, and 110d, the flow rate of hydraulic oil is throttled when the hydraulic cylinder 7 is about to contract. Therefore, the leg member 3 gently rotates in the bending direction with respect to the support member 2 . In this way, by switching the switching valve 110 between the blocking position 110a and the throttle positions 110b, 110c, and 110d, the knee joint 5 can be moved in accordance with the movement of the user's knee joint 5, which varies according to differences in walking speed and stride length. can. Therefore, it is possible to provide the hydraulic prosthesis 1 that can move according to the difference in walking motion of the user.

Further, the hydraulic prosthesis 1 is provided between a foot member 4 connected to the lower leg member 3 so as to be rotatable in the plantar flexion direction and the dorsiflexion direction, and between the lower leg member 3 and the leg member 4 . A hydraulic cylinder 8 that contracts when the leg member 4 rotates in the dorsiflexion direction, a piston-side chamber 74 that discharges hydraulic oil when the hydraulic cylinder 7 contracts, and a hydraulic oil discharges when the hydraulic cylinder 8 contracts. a rod side chamber 75 to which hydraulic oil is supplied when the hydraulic cylinder 7 is contracted; and a rod side chamber 85 to which hydraulic oil is supplied when the hydraulic cylinder 8 is contracted. and a third communicating path 103 communicating between the second communicating path 102 and the first communicating path 101. The switching valve 110 is provided in the third communicating path 103. to switch the flow of hydraulic oil flowing from the first communication path 101 to the second communication path 102 .

In this configuration, when the user walks forward and the bottom of the foot member 4 that has stepped forward touches the ground, the ankle joint 6 is rotated in the plantar flexion direction and the knee joint 5 is slightly bent. is doing. When the user moves forward further, the ankle joint 6 rotates in the dorsiflexion direction and the knee joint 5 rotates in the extension direction. At this time, if the switching valve 110 is switched to the shutoff position 110a, the hydraulic oil discharged from the hydraulic cylinder 8 flows through the first communication passage 101 to the hydraulic cylinder 7 as the hydraulic cylinder 8 gradually contracts. , the hydraulic cylinder 7 is gradually extended. Therefore, the hydraulic cylinders 7 and 8 can cause the knee joint portion 5 and the ankle joint portion 6 to move in accordance with the user's walking motion.

Further, in the hydraulic prosthesis 1, the throttling position has a plurality of throttling positions 110b, 110c, and 110d with mutually different throttling amounts of hydraulic oil.

In this configuration, for example, when the user descends stairs, the ankle joint 6 is required to rotate in the dorsiflexion direction and the knee joint 5 rotates in the flexion direction. In such a case, the switching valve 110 has a plurality of throttle positions 110b, 110c, and 110d with different throttle amounts, so that the hydraulic oil discharged from the piston-side chamber 74 of the hydraulic cylinder 7 is dissipated when walking on flat ground. Different throttle amounts can be supplied to the rod side chamber 75 of the hydraulic cylinder 7 . Therefore, the user can take natural walking motions using the hydraulic prosthesis 1 not only when walking on flat ground but also when going up and down stairs.

In the hydraulic prosthesis 1, the switching valve 110 is a check valve that allows the flow of hydraulic oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 expands and blocks the flow of hydraulic oil when it contracts. 130.

In this configuration, the provision of the check valve 130 allows the hydraulic cylinder 7 to extend regardless of the state of the hydraulic cylinder 8 . Therefore, the movement of extending the knee joint portion 5 can be performed quickly regardless of the movement of the ankle joint portion 6 .

Also, in the hydraulic prosthesis 1 , the check valve 130 is provided within the spool 121 .

In this configuration, the check valve 130 is provided in the spool 121, so that the hydraulic prosthesis 1 can be made smaller and lighter.

In addition, the hydraulic prosthesis 1 includes a coil spring 9 that biases the support member 2 so as to rotate with respect to the lower leg member 3 in the extension direction, and a foot member so as to rotate with respect to the lower leg member 3 in the plantar flexion direction. and a coil spring 10 biasing 4.

In this configuration, the coil spring 9 biases the support member 2 with respect to the lower leg member 3 in the extension direction, and the coil spring 10 biases the leg member 4 with respect to the lower leg member 3 in the plantar flexion direction. The knee joint part 5 and the ankle joint part 6 can be returned to their natural state during the leg period.

In addition, in the hydraulic prosthesis 1, the switching valve 110 is attached to the hydraulic cylinder 7 so that the expansion/contraction direction of the hydraulic cylinder 7 is the longitudinal direction.

In this configuration, since the longitudinal direction of the switching valve 110 coincides with the expansion and contraction direction of the hydraulic cylinder 7 , the switching valve 110 is provided along the hydraulic cylinder 7 and can be prevented from protruding significantly from the hydraulic cylinder 7 .

The hydraulic prosthesis 1 further includes an accumulator 140 that is attached to the hydraulic cylinder 7 and stores hydraulic oil when at least one of the hydraulic cylinder 7 and the hydraulic cylinder 8 contracts. The accumulator 140 is provided at the front or rear, and the accumulator 140 is provided at a position opposite to the switching valve 110 with the hydraulic cylinder 7 interposed therebetween.

In this configuration, the switching valve 110 and the accumulator 140 are provided in front and behind the hydraulic cylinder 7 . Accordingly, it is possible to prevent the switching valve 110 and the accumulator 140 from interfering with the bending and extending motions of the knee joint portion 5 . Moreover, the switching valve 110 and the accumulator 140 are provided along the hydraulic cylinder 7, and can be formed in the same shape as the leg of an able-bodied person.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of application examples of the present invention, and the technical scope of the present invention is not limited to the specific configurations of the above embodiments. do not have.

For example, in the above embodiment, the case where the hydraulic prosthesis 1 includes the hydraulic cylinder 7 and the hydraulic cylinder 8 has been described. An accumulator 140 may be provided.

In this case, when the user walks on a flat ground, switching the switching valve 110 between the shutoff position 110a and the throttle positions 110b, 110c, and 110d allows the user's knee joint portion 5 to operate differently depending on the walking speed and stride length. You can move according to your movements. Therefore, in this case as well, it is possible to provide a hydraulic prosthesis capable of moving in accordance with the difference in walking motion of the user.

Alternatively, the hydraulic cylinder 7 may be arranged such that the cylinder portion 71 is attached to the support member 2 and the rod 72 is attached to the lower leg member 3 . Similarly, the hydraulic cylinder 8 may be arranged such that the cylinder portion 81 is attached to the leg member 4 and the rod 82 is attached to the crus member 3 .

In this case, in the hydraulic cylinders 7 and 8, the rods 72 and 82 correspond to one end, the rod side chambers 75 and 85 correspond to one side pressure chambers, and the piston side chambers 74 and 84 correspond to the other side pressure chambers. .

Further, the walking assist device is not limited to the hydraulic prosthetic leg 1, and may be a power assist device used by users with weak legs such as disabled people and elderly people. The power assist device may be used by a healthy person to reduce the load of walking motion. In this case, the support member 2 is provided along the user's thigh and attached to the thigh from the outside, and the lower leg member 3 is provided along the user's lower leg and attached to the lower leg. Attached from the outside, the foot member 4 is provided along the foot of the user and attached to the foot from the outside. As a result, the walking motion of the user can be assisted with natural motion.

Moreover, the hydraulic circuit 100 of the present embodiment can be applied to a power assist device that assists the user's arm motion instead of assisting the user's walking motion. In this case, a member corresponding to the support member 2 is provided along the user's upper arm and attached to the upper arm from the outside, and a member corresponding to the lower leg member 3 is provided along the user's forearm. A member corresponding to the leg member 4 is provided along the user's hand and attached to the hand from the outside.

DESCRIPTION OF SYMBOLS 1... Hydraulic prosthesis (hydraulic prosthesis, walking assistance device), 2... Supporting member, 3... Lower leg member, 4... Foot member, 7... Hydraulic cylinder (first hydraulic cylinder) , 8... hydraulic cylinder (second hydraulic cylinder), 9... coil spring (first biasing member), 10... coil spring (second biasing member), 74... piston side chamber ( one side pressure chamber), 75 rod side chamber (other side pressure chamber), 84 piston side chamber (one side pressure chamber), 85 rod side chamber (other side pressure chamber), 102 second Two communication paths 103 Third communication path 110 Switching valve 110a Shutoff position 110b First throttle position 110c Second throttle position 110d Third 3 Throttle position 111 First housing (main body) 121 Spool 130 Check valve 140 Accumulator

Claims (8)

a support member attached to the user's thigh;
a lower leg member that is rotatably connected to the support member in a bending direction and an extending direction;
a first hydraulic cylinder provided between the support member and the lower leg member and contracting when the lower leg member rotates in a bending direction with respect to the support member;
a switching valve having a main body and a spool that moves along the inner circumference of the main body, the switching valve switching the flow of the liquid in the first hydraulic cylinder according to the position of the spool with respect to the main body;
with
The switching valve has a blocking position that blocks the flow of liquid when the first hydraulic cylinder is about to contract, and a throttle position that throttles the flow rate of liquid when the first hydraulic cylinder contracts. ,
A walking assistance device characterized by: The walking assistance device according to claim 1,
a foot member rotatably connected to the lower leg member in the plantar flexion direction and the dorsiflexion direction;
a second hydraulic cylinder provided between the lower leg member and the leg member and contracting when the leg member rotates in the dorsiflexion direction with respect to the lower leg member;
a first communication passage for communicating between a one-side pressure chamber that discharges liquid when the first hydraulic cylinder contracts and a one-side pressure chamber that discharges liquid when the second hydraulic cylinder contracts;
a second communication passage for communicating between the other side pressure chamber to which liquid is supplied when the first hydraulic cylinder contracts and the other side pressure chamber to which liquid is supplied when the second hydraulic cylinder contracts; ,
a third communication path that connects the second communication path and the first communication path;
further comprising
The switching valve is provided in the third communication path and switches the flow of the liquid flowing from the first communication path to the second communication path.
A walking assistance device characterized by: The walking assistance device according to claim 2,
The throttling position has a plurality of throttling positions with different throttling amounts of the liquid.
A walking assistance device characterized by: The walking assistance device according to claim 2 or 3,
The switching valve further has a check valve that allows the flow of liquid when at least one of the first hydraulic cylinder and the second hydraulic cylinder expands and blocks the flow of liquid when it contracts. ,
A walking assistance device characterized by: The walking assistance device according to claim 4,
wherein the check valve is provided within the spool;
A walking assistance device characterized by: The walking assistance device according to any one of claims 2 to 5,
a first biasing member that biases the support member to rotate in the extension direction with respect to the leg member;
a second biasing member biasing the leg member to rotate in the plantar flexion direction with respect to the crus member;
further comprising
A walking assistance device characterized by: The walking assistance device according to any one of claims 2 to 6,
The switching valve is attached to the first hydraulic cylinder so that the expansion and contraction direction of the first hydraulic cylinder is the longitudinal direction,
A walking assistance device characterized by: The walking assistance device according to any one of claims 2 to 7,
further comprising a pressure accumulator attached to the first hydraulic cylinder and storing liquid when at least one of the first hydraulic cylinder and the second hydraulic cylinder contracts;
The switching valve is provided in front or behind the first hydraulic cylinder,
The pressure accumulator is provided at a position opposite to the switching valve across the first hydraulic cylinder,
A walking assistance device characterized by:

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