Knee joint

Abstract

To provide a knee joint capable of obtaining regenerative power by using a resistance generated in operation of the knee joint.SOLUTION: A knee joint 1 includes: a thigh connection part 1A provided in a thigh part side; a cruris part 1B rotatably coupled to the thigh connection part; and a cylinder 1C (fluid pressure cylinder) coupled to the thigh connection part 1A and the cruris part 1B. The cylinder 1C is provided with a power generation part, and generates power by using a resistance generated in rotation of the cruris part with respect to the thigh connection part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a knee joint that generates electricity based on body movement. To Regarding. [Background technology]

[0002] Patent Document 1 describes a prosthetic device (prosthetic leg) that includes a thigh shaft, a lower leg shaft, a prosthetic foot, a joint, and a connection part. In the prosthetic device described in Patent Document 1, a moment sensor that determines an effective knee moment is provided at the joint, and a resistance means that provides flexion resistance and extension resistance is provided at the lower leg shaft. Each resistance means is controlled based on sensor data and an evaluation of the sensor data. In such a prosthetic leg, internal devices such as hydraulic equipment are controlled by supplying power to sensors and control devices from an internal power source. Therefore, a prosthetic leg that includes an internal device needs to be charged at a predetermined timing when the power source is consumed. Patent Document 2 describes a technology that generates power during the bending movement of the prosthetic leg and charges the storage battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2013-510605 [Patent Document 2] US Patent Application Publication No. 2015 / 0202057 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable that the prosthetic leg is configured to be easy to walk in and does not impair the original function even if the power generating device is present when the prosthetic leg is used by the user. According to the technology described in Patent Document 2, the power generation pattern is limited because the extension movement is performed using the power charged during the bending movement.

[0005] An object of the present invention is to provide a knee joint that is capable of obtaining regenerative power by utilizing the resistance generated during the movement of the knee joint. [Means for solving the problem]

[0006] The present invention is a knee joint comprising a thigh connection part provided on the thigh side, a lower leg part rotatably connected to the thigh connection part, and a power generating part that generates electricity using resistance generated by the rotation of the lower leg part relative to the thigh connection part.

[0007] The present invention may further include a fluid circuit through which a working fluid flows to generate the resistance, and the power generation section may generate power based on the flow of the working fluid.

[0008] In the present invention, the power generation section may include a gear motor that is driven by the working fluid to generate power.

[0009] The fluid circuit of the present invention may further include a control valve that adjusts the resistance based on the flow of the working fluid.

[0010] The present invention may further include a control unit that controls the operation of the control valve and operates using the electric power generated by the power generation unit.

[0011] The fluid circuit of the present invention may include a fluid pressure cylinder operated by the working fluid, and a power generation flow path that connects a first port and a second port in the fluid pressure cylinder separated by a piston moving within the fluid pressure cylinder, and in which the power generation unit is provided midway.

[0012] The present invention may further comprise a control valve provided in the power generation flow path for controlling the relationship between the flow rate of the working fluid flowing through the power generation flow path and a differential pressure caused by a pressure loss.

[0013] Furthermore, the power generation flow path of the present invention may include another flow path connecting the first port and the second port, and another control valve may be provided in the other flow path to control the relationship between the flow rate of the working fluid flowing therethrough and the differential pressure generated by pressure loss.

[0014] Furthermore, the power generation flow path of the present invention may include a first parallel flow path having a first parallel control valve through which the working fluid flows from the first port to the second port and which adjusts a flow rate of the working fluid, and a second parallel flow path through which the working fluid flows from the second port to the first port and which has a second parallel control valve which adjusts a flow rate of the working fluid, and the control unit may independently control the first parallel control valve or the second parallel control valve to adjust the flow rate of the working fluid in a flow direction to the power generation unit.

[0015] The present invention may also include a first check valve in the first power generation flow path that limits the flow of the working fluid from the second port to the first port, and a second check valve in the second power generation flow path that limits the flow of the working fluid from the first port to the second port.

[0016] Furthermore, the power generation flow path of the present invention may include a first flow path connecting one end side of an intermediate flow path in which the power generation unit is provided and the first port, a second flow path connecting the one end side of the intermediate flow path and the second port, a third flow path connecting the other end side of the intermediate flow path and the first port, and a fourth flow path connecting the other end side of the intermediate flow path and the second port, wherein the first flow path is provided with a first control valve that adjusts a flow rate of the working fluid, the second flow path is provided with a second control valve that adjusts the flow rate of the working fluid, the third flow path is provided with a third check valve that limits the flow of the working fluid in a flow direction from the first port to the intermediate flow path and allows the flow of the working fluid in a flow direction from the intermediate flow path to the first port, and the fourth flow path is provided with a fourth check valve that limits movement of the working fluid in the flow direction from the second port to the intermediate flow path and allows the flow of the working fluid in the flow direction from the intermediate flow path to the second port.

[0017] Furthermore, the power generation flow path of the present invention may include a first flow path and a second flow path connecting in parallel one end side of an intermediate flow path in which the power generation unit is provided and the second port, and a third flow path and a fourth flow path connecting in parallel the other end side of the intermediate flow path and the first port, wherein the first flow path is provided with a first control valve that adjusts a flow rate of the working fluid, the third flow path is provided with a second control valve that adjusts the flow rate of the working fluid, the second flow path is provided with a third check valve that allows the working fluid to flow from the intermediate flow path to the second port and restricts the flow of the working fluid from the second port to the intermediate flow path, and the fourth flow path is provided with a fourth check valve that allows the working fluid to flow from the intermediate flow path to the first port and restricts the flow of the working fluid from the first port to the intermediate flow path.

[0018] The present invention may also include a bypass flow passage connecting the one end side and the other end side of the intermediate flow passage, and a bypass control valve or a bypass relief valve provided in the bypass flow passage and adjusting a flow rate of the working fluid flowing through the bypass flow passage.

[0019] The present invention includes a control unit that controls the operation of the control valve and operates using the power generated by the power generation unit, and the control unit may arbitrarily adjust the other control valve when a resistance weaker than the power generation resistance generated by the power generation unit is to be generated, and may arbitrarily adjust the control valve when a resistance stronger than the power generation resistance is to be generated.

[0020] One aspect of the present invention includes a thigh connection part provided on the thigh side, a lower leg part rotatably connected to the thigh connection part, a power generation part that generates power using resistance generated by rotation of the lower leg part relative to the thigh connection part, a fluid circuit in which the power generation part is provided and a working fluid that generates the resistance flows, a control valve provided in the fluid circuit and adjusts the resistance based on the flow of the working fluid, a control part that controls the operation of the control valve and operates using electric power generated by the power generation part, a fluid pressure cylinder provided in the fluid circuit and operated by the working fluid, and a power generation flow path in which the power generation part is provided and connects a first port and a second port in the fluid pressure cylinder partitioned by a piston that moves within the fluid pressure cylinder, and in which the power generation part is provided, a second flow passage connecting the one end side of the intermediate flow passage and the second port, a third flow passage connecting the other end side of the intermediate flow passage and the first port, and a fourth flow passage connecting the other end side of the intermediate flow passage and the second port, wherein the first flow passage is provided with a first control valve adjusting a flow rate of the working fluid, the second flow passage is provided with a second control valve adjusting a flow rate of the working fluid, the third flow passage is provided with a third check valve limiting the flow of the working fluid in a flow direction from the first port to the intermediate flow passage and allowing the flow of the working fluid in a flow direction from the intermediate flow passage to the first port, and the fourth flow passage is provided with a fourth check valve limiting movement of the working fluid in the flow direction from the second port to the intermediate flow passage and allowing the flow of the working fluid in the flow direction from the intermediate flow passage to the second port.

[0021] One aspect of the present invention includes a thigh connection part provided on a thigh side, a lower leg part rotatably connected to the thigh connection part, a power generation part that generates power using resistance generated by rotation of the lower leg part relative to the thigh connection part, a fluid circuit in which the power generation part is provided and a working fluid that generates the resistance flows, a control valve provided in the fluid circuit and adjusts the resistance based on the flow of the working fluid, a control part that controls the operation of the control valve and operates using electric power generated by the power generation part, a fluid pressure cylinder provided in the fluid circuit and operated by the working fluid, and a power generation flow path in which the power generation part is provided, the power generation flow path connecting a first port and a second port in the fluid pressure cylinder partitioned by a piston that moves within the fluid pressure cylinder, the power generation flow path being a first flow path and a second flow path connecting in parallel one end side of an intermediate flow path in which the power generation part is provided and the second port. a third flow path and a fourth flow path connecting the other end side of the intermediate flow path and the first port in parallel, and a bypass flow path connecting the one end side of the power generation unit and the other end side, wherein the first flow path is provided with a first control valve that adjusts a flow rate of the working fluid, the third flow path is provided with a second control valve that adjusts the flow rate of the working fluid, the second flow path is provided with a third check valve that allows the working fluid to flow from the intermediate flow path to the second port and limits the flow of the working fluid from the second port to the intermediate flow path, the fourth flow path is provided with a fourth check valve that allows the working fluid to flow from the intermediate flow path to the first port and limits the flow of the working fluid from the first port to the intermediate flow path, and the bypass flow path is provided with a bypass control valve or a bypass relief valve that adjusts the flow rate of the working fluid flowing through the bypass flow path.

[0022] One aspect of the present invention is a knee joint power generation method, in which a knee joint includes a thigh connection part provided on the thigh side and a lower leg part rotatably connected to the thigh connection part, and power is generated using resistance generated by rotation of the lower leg part relative to the thigh connection part.

[0023] One aspect of the present invention is a program for a knee joint having a thigh connection part provided on the thigh side and a lower leg part rotatably connected to the thigh connection part, which generates electricity by having a control device control the resistance value generated by rotation of the lower leg part relative to the thigh connection part. Effect of the Invention

[0024] According to the present invention, regenerative power can be obtained by utilizing the resistance generated during the movement of the knee joint. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a cross-sectional view showing the configuration of a knee joint according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing a schematic configuration of a cylinder of a knee joint. [Diagram 3] FIG. 2 is a block diagram showing the configuration of a control device that controls a knee joint. [Figure 4] FIG. 4 is a diagram illustrating a schematic configuration of a hydraulic circuit for a cylinder having a power generating unit. [Diagram 5] FIG. 11 is a diagram illustrating a schematic configuration of a hydraulic circuit according to a second embodiment. [Figure 6] 4 is a flowchart showing a control method for adjusting the resistance of the knee joint 1. [Figure 7] FIG. 11 is a diagram illustrating a schematic configuration of a hydraulic circuit according to a third embodiment. [Figure 8] 11A and 11B are diagrams illustrating the operation of the hydraulic circuit during bending motion. [Figure 9] 11A and 11B are diagrams illustrating the operation of the idling circuit when decelerating and stopping a bending motion. [Figure 10] 13A and 13B are diagrams illustrating the operation of the hydraulic circuit during extension. [Figure 11] 13A and 13B are diagrams illustrating the operation of the idling circuit when decelerating and stopping the extension operation. [Figure 12] FIG. 13 is a diagram showing a configuration of a hydraulic circuit according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The basic configuration of the knee joint according to the embodiment will be described below.

[0027] As shown in FIG. 1, the knee joint 1 is a device that supports the lower body part from the thigh of a user (a person wearing the knee joint 1). The knee joint 1 includes a thigh connection part 1A that is connected to the thigh, a lower leg part 1B that is rotatably connected to the thigh connection part 1A, and a cylinder 1C (a fluid pressure cylinder) that is connected to the thigh connection part 1A and the lower leg part 1B. A front link part 11 is rotatably connected to the front between the thigh connection part 1A and the lower leg part 1B. A rear link part 12 is rotatably connected to the rear between the thigh connection part 1A and the lower leg part 1B. The knee joint 1 is controlled by a control device 10 (see FIG. 3) described later. The control device 10 is provided at an arbitrary position in the knee joint 1.

[0028] An upper part of the front link part 11 is rotatably connected to the thigh connection part 1A via a first shaft 13. A lower part of the front link part 11 is rotatably connected to the lower leg part 1B via a third shaft 15. An upper part of the rear link part 12 is rotatably connected to the thigh connection part 1A via a second shaft 14. A lower part of the rear link part 12 is rotatably connected to the lower leg part 1B via a fourth shaft 16.

[0029] A socket (see, for example, FIG. 1 of JP 2017-6339 A) that is attached to the lower end of the user's thigh is connected to the thigh connection part 1A. With the above-mentioned configuration, the front link part 11 and the rear link part 12 of the lower leg part 1B become a rotation mechanism corresponding to the knee axis, and the lower leg part 1B rotates with respect to the thigh connection part 1A. In other words, the thigh connection part 1A, the lower leg part 1B, the front link part 11, and the rear link part 12 form a four-joint link. As a result, as described above, the lower leg part 1B can rotate around the knee axis (virtual axis) with respect to the thigh connection part 1A.

[0030] The rotation of the thigh connection part 1A and the lower leg part 1B is restricted or assisted by a telescopic cylinder 1C (fluid pressure cylinder). The cylinder 1C is disposed at a position corresponding to the calf. The upper end of the cylinder 1C is rotatably connected to the thigh connection part 1A. The lower end of the cylinder 1C is rotatably connected to the lower leg part 1B. The cylinder 1C comprises a cylinder tube 1C1 provided substantially upside down, a piston 1C2 provided movably within the cylinder tube 1C1, and a piston rod 1C3 connected above the piston 1C2. The cylinder 1C may be provided on the thigh connection part 1A side.

[0031] The cylinder tube 1C1 is formed in a cylindrical shape with a bottom. The upper end of the cylinder tube 1C1 is closed by a lid 1CF. A through hole 1CH is formed in the center of the lid 1CF. A piston rod 1C3 is inserted into the through hole. The lower end of the cylinder tube 1C1 is rotatably connected to the lower leg portion 1B side via a connecting portion 1C13. The inside of the cylinder tube 1C1 is partitioned by a piston 1C2 formed in a disk shape. The piston 1C2 is formed, for example, in an outer shape slightly smaller than the inner diameter of the cylinder tube 1C1. The cylinder tube 1C1 may be formed in a shape other than a cylindrical shape.

[0032] The lower end of the piston rod 1C3 is connected to the upper surface of the piston 1C2. The piston rod 1C3 is formed in a cylindrical shape. The piston rod 1C3 protrudes from the through hole 1CH to the outside of the cylinder tube 1C1. The upper end of the piston rod 1C3 is rotatably connected to the thigh connection part 1A via a connection part 1C13.

[0033] With the above configuration, the knee joint 1 rotates at the lower leg part 1B relative to the thigh connection part 1A, and the piston rod 1C3 expands and contracts relative to the cylinder tube 1C1 in conjunction with the rotation. At this time, resistance is generated when the piston 1C2 moves inside the cylinder tube 1C1, so the cylinder 1C applies resistance to the rotation of the lower leg part 1B relative to the thigh connection part 1A.

[0034] As shown in Fig. 2, the cylinder 1C is provided with a fluid circuit for controlling resistance. The inside of the cylinder tube 1C1 is partitioned by a piston 1C2. The inside of the cylinder tube 1C1 is defined as a first port 1C11 located on the piston rod 1C3 side of the space partitioned by the piston 1C2, and a second port 1C12 located on the opposite side of the piston rod 1C3 across the piston 1C2.

[0035] The inside of the cylinder tube 1C1 is filled with a working fluid. The working fluid is, for example, hydraulic oil. The working fluid may be a fluid other than hydraulic oil. The first port 1C11 and the second port 1C12 are connected by a flow path 1Q1 through which the working fluid flows. The extension side valve 1G and the extension side check valve 1G1 are connected in series to the flow path 1Q1. The connection order of the extension side valve 1G and the extension side check valve 1G1 may be interchanged. In addition, the first port 1C11 and the second port 1C12 are connected by a flow path 1Q2 through which the working fluid flows. The bending side valve 1H and the bending side check valve 1H1 are connected in series to the flow path 1Q2. The connection order of the bending side valve 1H and the bending side check valve 1H1 may be interchanged.

[0036] 3 shows the configuration of a control device 10 that controls the knee joint 1. The control device 10 includes, for example, a detection unit 1D, a control unit 1E, an extension side valve 1G, an extension side check valve 1G1, a flexion side valve 1H, a flexion side check valve 1H1, a battery 1J, a battery state acquisition unit 1K, and a power generation unit 20. The power generation unit 20 will be described later.

[0037] The detection unit 1D directly or indirectly acquires information regarding the posture and load state of the knee joint 1 and the relative position between the thigh connection part 1A and the lower leg part 1B. The detection unit 1D acquires information regarding the posture and load state of the knee joint 1 and the relative position between the thigh connection part 1A and the lower leg part 1B by having, for example, a knee angle sensor, a 6-axis inertial sensor, a load sensor, etc., as described in FIG. 2 of JP 2017-6339 A. In another example, the detection unit 1D may acquire information regarding the relative position between the thigh connection part 1A and the lower leg part 1B by measuring the distance, for example, as a position detection unit described in FIG. 2 of JP 2019-180887 A, or may acquire information regarding the posture and load state of the knee joint 1 and the relative position between the thigh connection part 1A and the lower leg part 1B by measuring the inclination angle, for example, as a position detection unit described in FIG. 6 of JP 2019-180887 A.

[0038] The control unit 1E controls the resistance of the cylinder 1C based on the detection result of the detection unit 1D. The control unit 1E estimates the motion state of the user from the detection result of the detection unit 1D. That is, the control unit 1E controls the resistance of the cylinder 1C to generate a resistance according to the motion state of the user. The control unit 1E operates using the power generated by the power generation unit 20. In order to stabilize the supplied power, the control unit 1E charges the power generated by the power generation unit 20 to the battery 1J and operates based on the power stored in the battery 1J.

[0039] The extension side valve 1G adjusts the amount of working fluid flowing through the flow path 1Q1 to limit the extension of the cylinder 1C. Adjusting the extension side valve 1G restricts the flow of working fluid from the first port 1C11 to the second port 1C12, limiting the extension of the knee joint 1. The opening of the extension side valve 1G is controlled by the control unit 1E. When the opening of the extension side valve 1G is reduced, it becomes more difficult for the working fluid in the first port 1C11 of the cylinder tube 1C1 to flow into the second port 1C12 via the extension side valve 1G.

[0040] In other words, when the opening of the extension side valve 1G is reduced, it becomes difficult for the cylinder 1C to extend, and therefore for the knee joint 1 to extend. That is, when it is necessary to limit the extension of the knee joint 1, the control unit 1E reduces the opening of the extension side valve 1G. The extension side check valve 1G1 prevents the fluid in the second port 1C12 from flowing back to the first port 1C11 via the extension side valve 1G when the extension side valve 1G is open.

[0041] The flexion side valve 1H adjusts the amount of working fluid flowing through the flow path 1Q2, limiting the contraction of the cylinder 1C. Adjusting the flexion side valve 1H restricts the flow of working fluid from the second port 1C12 to the first port 1C11, limiting the bending of the knee joint 1. The opening of the flexion side valve 1H is controlled by the control unit 1E. When the opening of the flexion side valve 1H is reduced, it becomes more difficult for the fluid in the second port 1C12 of the cylinder tube 1C1 to flow into the first port 1C11 via the flexion side valve 1H.

[0042] In other words, when the opening of the bend side valve 1H is reduced, the cylinder 1C becomes less likely to retract, and the knee joint 1 becomes less likely to bend. In other words, when it is necessary to limit the bending of the knee joint 1, the control unit 1E reduces the opening of the bend side valve 1H. The bend side check valve 1H1 prevents the fluid in the first port 1C11 from flowing back to the second port 1C12 via the bend side valve 1H when the bend side valve 1H is open.

[0043] The control unit 1E performs various calculation processes based on the detection results of the detection unit 1D. The battery 1J supplies power to the parts constituting the knee joint 1, such as the detection unit 1D and the control unit 1E (more specifically, the parts that consume power to operate). The battery status acquisition unit 1K acquires the status of the battery 1J (e.g., data such as the state of charge (SOC) (remaining capacity), capacity, open circuit voltage, and open circuit potential). The battery 1J stores the power generated in the power generation unit 20. The amount of power stored in the battery 1J is controlled by the control unit 1E based on the data acquired by the battery status acquisition unit 1K, and load charging and over-discharge are prevented. The battery 1J is, for example, composed of a secondary battery. The battery 1J may be composed of a condenser or a capacitor.

[0044] The control unit 1E estimates the user's motion state, whether the user is walking or non-walking, or, if walking, which phase of walking (swing phase flexion, swing phase extension, stance phase, etc.) the user is in, based on the detection result of the detection unit 1D. When the user's walking phase is swing phase flexion, the control unit 1E controls the flexion resistance to be small, and when the user is in stance phase, the control unit 1E controls the flexion resistance to be large. When the control unit 1E estimates that the user's motion state is a non-walking state, it sets the knee joint 1 to, for example, a maximum flexion mode, a bicycle free mode, a seated free mode, a safety lock mode, a standing stationary mode, etc.

[0045] In the above embodiment, flow paths 1Q1 and 1Q2 may be omitted. In this case, the control unit 1E may adjust the flow rate of the working fluid flowing through flow path 1Q3 during bending or extension by adjusting the power generation resistance of the power generation unit 20. That is, the control unit 1E may change the rotational resistance of the gear motor by adjusting the power generation resistance generated between the terminals of the gear motor in the power generation unit 20 or the conduction time to the gear motor based on PWM (Pulse Width Modulation) control or the like.

[0046] As described above, the knee joint 1 can generate power using the resistance generated during bending or extending motion, and use the regenerated power as power supply for the knee joint 1. The knee joint 1 can generate power by utilizing the energy of the working fluid flowing through the fluid circuit that generates resistance to bending or extending motion.

[0047] [First embodiment] The power generating unit 20 in the knee joint 1 will be described below. As shown in Fig. 4, the power generating unit 20 is provided in the cylinder 1C in the knee joint 1. The power generating unit 20 generates power using resistance generated during either bending or extension at the knee joint of the body. The power generating unit 20 generates power, for example, using resistance generated during rotation around the knee axis that rotatably connects the thigh connection part 1A and the lower leg part 1B. In the example of Fig. 4, the power generating unit 20 is configured to generate power during bending in which the cylinder 1C is contracted, and to generate power during extension in which the cylinder 1C is extended.

[0048] The cylinder 1C includes a fluid circuit 1Q (hydraulic circuit) through which a working fluid flows. The fluid circuit 1Q generates resistance in the cylinder 1C by generating a pressure difference caused by pressure loss of the working fluid. The resistance of the working fluid is generated based on a pressure difference caused by pressure loss between the pressure of a flow path connected to one side of the power generation unit 20 and the pressure of a flow path connected to the other side. The resistance force generated in the fluid circuit 1Q is calculated by multiplying this pressure difference by the area of ​​the piston 1C2.

[0049] The fluid circuit 1Q includes a cylinder 1C operated by a working fluid, a flow path 1Q3 (power generation flow path) that connects a first port 1C11 and a second port 1C12 in the cylinder 1C partitioned by a piston 1C2 moving in the cylinder 1C and has a power generation unit 20 provided in the middle, and other flow paths. The other flow paths include, for example, a flow path 1Q1 (first parallel flow path) and a flow path 1Q2 (second parallel flow path). The flow path 1Q3 connects the first port 1C11 and the second port 1C12. In the fluid circuit 1Q, the flow paths 1Q1 and 1Q2, which are the other flow paths as viewed from the flow path 1Q3, are provided in parallel. By providing the flow paths 1Q1 and 1Q2, power can be generated based on the resistance generated during the extension or bending motion.

[0050] When the piston rod 1C3 is extended, the working fluid is discharged from the first port 1C11, flows through the flow passages 1Q3 and 1Q1, and returns to the second port 1C12. When the piston rod 1C3 is contracted, the working fluid is discharged from the second port 1C12, flows through the flow passages 1Q3 and 1Q2, and returns to the first port 1C11. The flow passages 1Q1 and 1Q2 are bypass flow passages parallel to the flow passage 1Q3. A control valve (extension side valve 1G) described later is connected to the flow passage 1Q1. A control valve (bending side valve 1H) described later is connected to the flow passage 1Q2. Power is generated in the power generation unit 20 based on the working fluid flowing through the flow passage 1Q3. The resistance in the power generation unit 20 is adjusted based on the opening of the extension side valve 1G or the bending side valve 1H.

[0051] The power generating unit 20 is provided, for example, in the middle of the flow path 1Q3. The power generating unit 20 generates power based on the flow of the working fluid. The power generating unit 20 includes, for example, a gear motor that is driven by the working fluid to generate power. The gear motor includes, for example, a pump such as a trochoid pump having a trochoid gear or a gear pump of an external gear type or an elliptical gear type, and a motor connected to the pump. The gear motor can increase the rotation speed of the pump to generate a large electromotive force in the motor. (By providing the gear pump in the power generating unit 20, a large torque can be obtained even if the power generating unit 20 is made small, and a large hydraulic resistance can be generated.) The gear motor can improve the power generation efficiency.

[0052] The resistance generated in the knee joint 1 is adjusted based on the amount of power generated by the power generation unit 20. The amount of power generation is adjusted by changing the power generation resistance generated between the terminals of the gear motor, and the power generation resistance is adjusted based on PWM (Pulse Width Modulation) control of a control circuit (not shown) provided between the terminals of the gear motor. The control circuit is composed of transistor elements such as FETs connected between the terminals of the gear motor, for example. The control circuit adjusts the ON / OFF times of the transistor elements by PWM, thereby adjusting the power generation resistance generated in the power generation unit 20.

[0053] The control unit 1E controls the resistance value generated in the fluid circuit 1Q to adjust the amount of power generated by the power generation unit 20. The flow rate of the working fluid is determined by the knee flexion and extension speed, and cannot be directly controlled. The control unit 1E adjusts the relationship between the flow rate of the working fluid flowing through the fluid circuit 1Q and the differential pressure (pressure loss) using the control valve and the power generation unit 20 to arbitrarily adjust the resistance generated in the knee joint. The control unit 1E independently controls the extension side valve 1G (first parallel control valve) or the flexion side valve 1H (second parallel control valve) to adjust the flow rate of the working fluid in the flow direction to the power generation unit 20. Here, the differential pressure is calculated by a constant that changes depending on the valve × flow rate ^α. α is theoretically 2. For example, the control unit 1E PWM controls the ON / OFF time of a control circuit connected between the terminals of a gear motor in the power generation unit 20 to adjust the relationship between the flow rate of the working fluid flowing through the fluid circuit 1Q and the differential pressure. The control unit 1E adjusts the resistance generated in the knee joint 1 by controlling the control valve in addition to the power generation resistance generated in the power generation unit 20.

[0054] According to the knee joint 1, since the power generating unit 20 is provided with a gear motor, even if the knee joint 1 is made small, it is possible to obtain a large torque and generate a large hydraulic resistance. According to the knee joint 1, since the gear motor is provided, even if the rotation of the gear pump unit is slow, the speed is increased by the gears, so that the motor can be rotated at high speed, an electromotive force can be generated, and regenerative power can be obtained. Furthermore, according to the knee joint 1, it is also possible to generate a large hydraulic resistance in the gear pump based on the generation of regenerative power. According to the knee joint 1, it is possible to generate power by utilizing the resistance of the working fluid flowing in the fluid circuit that operates in response to the bending or extension movement.

[0055] According to the knee joint 1, by connecting a control valve to the power generating unit 20, the power generating resistance generated in the power generating unit 20 can be adjusted as desired. According to the knee joint 1, by providing another flow path and another control valve in parallel with the power generating unit 20, it is possible to generate a weaker resistance compared to the power generating resistance generated in the power generating unit. According to the knee joint 1, the power generating resistance generated in the power generating unit 20 can be adjusted based on the on / off between the terminals of the gear motor. According to the knee joint 1, by providing another flow path and another control valve, it is possible to generate a weaker resistance beyond the adjustment range of the gear motor.

[0056] The power generating unit 20 may operate using the electric power generated by the power generating unit 20, or may be charged in the battery 1J. In the fluid circuit 1Q, control valves (extension side valve 1G and bending side valve 1H) controlled by the control unit 1E are provided. The extension side valve 1G and the bending side valve 1H are parallel control valves connected to a flow path 1Q1 (first power generation flow path) and a flow path 1Q2 (second power generation flow path) that are provided in parallel to the flow path 1Q3. The parallel control valve generates a resistance that is weaker than the resistance generated by the power generating unit 20. When a resistance weaker than the resistance R1 generated by the power generating unit 20 is to be generated, the control unit 1E arbitrarily adjusts the parallel control valve.

[0057] The extension-side valve 1G (first parallel control valve) adjusts the pressure to be lowered during extension (when the first port 1C11 becomes high pressure). The bending-side valve 1H (second parallel control valve) adjusts the pressure to be lowered during bending (when the second port 1C12 becomes high pressure). In the flow path 1Q1, an extension-side check valve 1G1 (first check valve) is connected in series to the extension-side valve 1G. The extension-side check valve 1G1 allows the working fluid to flow in the flow direction from the first port 1C11 to the second port 1C12, and restricts the flow in the flow direction from the second port 1C12 to the first port 1C11. In the flow path 1Q2, a bending-side check valve 1H1 (second check valve) is connected in series to the bending-side valve 1H. By providing the extension-side check valve 1G1 and the bending-side check valve 1H1, the resistance generated during the extension operation or the bending operation can be individually adjusted.

[0058] The flexion side check valve 1H1 allows the working fluid to flow in the flow direction from the second port 1C12 to the first port 1C11, and restricts the flow in the flow direction from the first port 1C11 to the second port 1C12. The extension side valve 1G and the flexion side valve 1H are control valves that are controlled by the control unit 1E and generate resistance by adjusting the relationship between the flow rate of the working fluid and the differential pressure caused by pressure loss. When the extension side valve 1G is a solenoid valve, the opening is adjusted by the number of times it is opened and closed. When the extension side valve 1G is a solenoid controlled valve, the opening is adjusted by the amount of opening. When the flexion side valve 1H is a solenoid valve, the opening is adjusted by the number of times it is opened and closed. When the flexion side valve 1H is a solenoid controlled valve, the opening is adjusted by the amount of opening.

[0059] In the fluid circuit 1Q, resistance (R1) based on the flow rate (I1) of the working fluid is generated in the power generation section 20, and resistance (R2) based on the flow rate (I2) of the working fluid is generated in the extension side valve 1G and the bending side valve 1H. The rigidity resistance of the fluid circuit 1Q is R1·R2 / (R1+R2). The flow rate (I1) of the working fluid in the power generation section 20 is I1=R2 / (R1+R2). The amount of electricity generated in the power generation section 20 is R1·I1=R1·R2 / (R1+R2).

[0060] In the fluid circuit 1Q, during an extension operation, the bending side check valve 1H1 prevents the working fluid from flowing through the flow passage 1Q2, and the working fluid flows in the direction from the first port 1C11 to the second port 1C12 via the flow passages 1Q3 and 1Q1. In the fluid circuit 1Q, during a bending operation, the extension side check valve 1G1 prevents the working fluid from flowing through the flow passage 1Q1, and the working fluid flows in the direction from the second port 1C12 to the first port 1C11 via the flow passages 1Q3 and 1Q2.

[0061] In the fluid circuit 1Q, for example, when the extension side valve 1G or the flexion side valve 1H is fully opened during an extension motion or a flexion motion, the working fluid flows through the flow path 1Q1 or 1Q2 without resistance, and the resistance of the fluid circuit 1Q becomes approximately zero regardless of the resistance (R1) of the power generation unit 20. In this case, the working fluid does not flow through the flow path 1Q3, and no power is generated in the power generation unit 20. In the operation of the knee joint 1, when it is necessary to reduce the flexion resistance (to accommodate quick movements), for example, during the flexion period of the swing phase, the power generation unit 20 becomes a resistance, so by fully opening the extension side valve 1G or the flexion side valve 1H, the resistance of the working fluid flowing through the fluid circuit 1Q can be made approximately zero.

[0062] In the fluid circuit 1Q, when the flow rate of the extension side valve 1G or the bending side valve 1H is narrowed during an extension operation or a bending operation, the resistance (R2) increases, the flow rate (I1) of the flow path 1Q3 increases, and power is generated in the power generation unit 20. That is, the power generation unit 20 generates power based on the flow of the working fluid in the flow direction permitted by the extension side check valve 1G1 (first check valve) and the bending side check valve 1H1 (second check valve).

[0063] In the fluid circuit 1Q, when the extension side valve 1G or the bending side valve 1H is fully closed, the resistance of the fluid circuit 1Q becomes R1, and the flow rate (I1) of the flow path 1Q3 generates power in the power generation unit 20. In this case, the movement of the cylinder 1C cannot be locked.

[0064] As described above, the knee joint 1 can generate electricity by the power generation unit using the resistance generated during either bending or extension of the knee joint of the body. The knee joint 1 regenerates power by using energy that was previously wasted to generate resistance during prosthetic limb movement, reducing the number of times the internal power supply needs to be charged and providing power for internal devices. The knee joint 1 operates the control unit based on the power generated internally, reducing or eliminating the need to charge the knee joint. The knee joint 1 regenerates power based on the energy generated by a person swinging their thighs, so it is possible to obtain regenerative energy that exceeds the amount of power consumed.

[0065] [Second embodiment] As shown in FIG. 5, in the fluid circuit 1Q, the flow path 1Q3 is provided with a first control valve 1M (control valve) connected in series to the power generation unit 20. The first control valve 1M is provided in the power generation flow path and controls the flow rate of the working fluid flowing through the flow path 1Q3. The first control valve 1M adds resistance to the power generation unit 20. As in the fourth embodiment, the control unit 1E independently controls the extension side valve 1G (first parallel control valve) or the bending side valve 1H (second parallel control valve) to adjust the flow rate of the working fluid in the flow direction to the power generation unit 20. When the control unit 1E generates a resistance R1 stronger than the resistance R1 generated by the power generation unit 20, the control unit 1E arbitrarily adjusts the first control valve 1M. The first control valve 1M is connected, for example, between the power generation unit 20 and the second port 1C12 in the flow path 1Q3. The first control valve 1M may be connected, for example, between the power generation unit 20 and the first port 1C11 in the flow path 1Q3.

[0066] In the fluid circuit 1Q, for example, when the extension side valve 1G or the bending side valve 1H is fully opened during an extension operation or a bending operation, the working fluid flows through the flow path 1Q1 or the flow path 1Q2 without resistance, and the resistance of the fluid circuit 1Q becomes approximately zero regardless of the resistance (R1) of the power generation unit 20. In this case, the working fluid does not flow through the flow path 1Q3, and power generation is not performed in the power generation unit 20. In the fluid circuit 1Q, when the flow rate of the extension side valve 1G or the bending side valve 1H is narrowed during an extension operation or a bending operation, the resistance (R2) increases, the flow rate (I1) of the flow path 1Q3 increases, and power generation is performed in the power generation unit 20.

[0067] In the fluid circuit 1Q, when the extension side valve 1G or the flexion side valve 1H is fully closed and the first control valve 1M is fully closed, the movement of the cylinder 1C can be locked. With the above configuration, a clutch capable of locking the movement of the knee joint 1 can be realized in the fluid circuit 1Q. Furthermore, the fluid circuit 1Q makes it possible to generate any resistance force even when the power is turned off, and can achieve a small and lightweight design.

[0068] When the resistance in the fluid circuit 1Q is set to R1 or more, when the first control valve 1M is fully opened, power is generated in the power generation unit 20 by the flow rate (I1) in the flow path 1Q3, and the resistance (R1) generated in the power generation unit 20 is combined with the resistance (R2) of the extension side valve 1G or the bending side valve 1H.

[0069] Next, a control method for the fluid circuit 1Q executed by the control unit 1E will be described.

[0070] 6 shows the flow of processing of the control method of the fluid circuit 1Q in the knee joint power generation method executed by the control unit 1E. The control unit 1E judges whether or not resistance is necessary in the extension or flexion of the knee joint 1 (step S100). If resistance is not necessary (step S100: No), the control unit 1E fully opens all of the control valves, the first control valve 1M, the extension side valve 1G, and the flexion side valve 1H (step S102). If resistance is necessary (step S: Yes), the control unit 1E judges whether or not the resistance generated by the knee joint 1 is stronger than the power generation resistance generated by the power generation unit 20 (step S104).

[0071] If a resistance stronger than the power generation resistance is required (step S104: Yes), the control unit 1E fully closes the extension side valve 1G or the bending side valve 1H and adjusts the first control valve 1M (step S106). If a resistance weaker than the power generation resistance is required (step S104: No), the control unit 1E fully opens the first control valve 1M and adjusts the extension side valve 1G or the bending side valve 1H, which are parallel control valves (step S108). The control unit 1E adjusts each control valve and causes the power generation unit 20 to generate power based on the bending operation or the extension operation (step S110).

[0072] As described above, according to the fluid circuit 1Q of the second embodiment, an appropriate resistance can be generated in the knee joint 1 based on the strength of the resistance generated in the knee joint 1 and the power generation resistance generated in the power generation section 20.

[0073] According to the knee joint 1 of the second embodiment, by connecting a control valve to the power generation unit 20, the power generation resistance generated in the power generation unit 20 can be adjusted as desired. According to the knee joint 1, by providing another flow path and another control valve in parallel with the power generation unit 20, it is possible to generate a weaker resistance compared to the power generation resistance generated in the power generation unit. According to the knee joint 1, the power generation resistance generated in the power generation unit 20 can be adjusted based on the on / off between the terminals of the gear motor. According to the knee joint 1, by providing another flow path and another control valve, it is possible to generate a weaker resistance beyond the adjustment range of the gear motor.

[0074] According to the knee joint 1, since the extension side check valve 1G1 (first check valve) and the flexion side check valve 1H1 (second check valve) are provided, the resistance generated during the extension movement or the flexion movement can be adjusted individually. According to the knee joint 1, since the flow path 1Q1 (first power generation flow path) and the flow path 1Q2 (second power generation flow path) are provided, the power generation can be generated based on the resistance generated during the extension movement or the flexion movement.

[0075] [Third embodiment] In the fluid circuit 1Q of the first and second embodiments, the working fluid circulating in the power generation unit 20 circulated in the opposite direction when the knee joint 1 was switched between bending and extending. In the power generation unit 20, the rotation of the gear motor rotor is accelerated based on the flow of the working fluid, so the rotational inertia of the rotor portion increases, and when the rotor rotates forward and backward repeatedly, the energy based on the rotation is lost each time, and the power generation efficiency decreases. To improve the power generation efficiency in the power generation unit 20, it is desirable for the working fluid to flow in one direction. The fluid circuit 1Q of the third embodiment is configured so that the working fluid circulating in the power generation unit 20 flows in one direction.

[0076] As shown in Fig. 7, the fluid circuit 1S according to the third embodiment is formed with a power generation flow path through which a working fluid flows. The power generation flow path includes an intermediate flow path 1SC in which a power generation section 20 is provided. A first flow path 1S1 connecting to the first port 1C11 and a second flow path 1S2 connecting to the second port 1C12 are connected to a connection part 21 on one end side of the intermediate flow path 1SC. A third flow path 1S3 connecting to the first port 1C11 and a fourth flow path 1S4 connecting to the second port 1C12 are connected to a connection part 22 on the other end side of the intermediate flow path 1SC.

[0077] The first flow passage 1S1 is provided with a first control valve 1M for adjusting the flow rate of the working fluid. The second flow passage 1S2 is provided with a second control valve 1N for adjusting the flow rate of the working fluid. The third flow passage 1S3 is provided with a third check valve 1H2 for restricting the flow of the working fluid in the flow direction from the first port 1C11 to the intermediate flow passage 1SC and allowing the flow of the working fluid in the flow direction from the intermediate flow passage 1SC to the first port 1C11. The fourth flow passage 1S4 is provided with a fourth check valve 1G2 for restricting the movement of the working fluid in the flow direction from the second port 1C12 to the intermediate flow passage 1SC and allowing the flow of the working fluid in the flow direction from the intermediate flow passage 1SC to the second port 1C12.

[0078] As shown in Figure 8, when the knee joint 1 bends in the fluid circuit 1S, the working fluid is discharged from the second port 1C12, flows through the second control valve 1N, the power generation unit 20, and the third check valve 1H2, and returns to the first port 1C11. According to the fluid circuit 1S, the resistance of the knee joint 1 can be adjusted by controlling the second control valve 1N, and electricity can be generated in the power generation unit 20. At this time, the working fluid also flows through the first control valve 1M, so the resistance of the knee joint 1 can be adjusted by adjusting the first control valve 1M.

[0079] As shown in Fig. 9, according to the fluid circuit 1S, when the bending motion of the knee joint 1 is decelerated or stopped, an idling circuit is formed in which the working fluid circulates through the power generation unit 20. The idling circuit is formed by a looped flow path connecting the second control valve 1N, the power generation unit 20, and the fourth check valve 1G2. As the working fluid circulates through the idling circuit, even when the bending motion is stopped, the regenerative motor in the power generation unit 20 is not braked and continues to rotate due to inertia, thereby continuing to generate power. In the power generation unit 20, the regenerative motor of the power generation unit 20 continues to rotate at all times, so there is no loss due to inertia and power generation performance is improved.

[0080] As shown in Fig. 10, according to the fluid circuit 1S, during extension of the knee joint 1, the working fluid is discharged from the first port 1C11, flows through the first control valve 1M, the power generation unit 20, and the fourth check valve 1G2, and returns to the second port 1C12. According to the fluid circuit 1S, the resistance of the knee joint 1 can be adjusted by controlling the first control valve 1M, and power can be generated in the power generation unit 20. At this time, the direction of the working fluid flowing through the power generation unit 20 is the same as the flow direction during bending. Therefore, according to the fluid circuit 1S, the power generation efficiency is improved compared to when the flow direction of the working fluid flowing through the power generation unit 20 is reversed.

[0081] Since the flow direction of the working fluid in the power generation unit 20 is constant, the regenerative motor of the power generation unit 20 is not braked and power generation continues. Since the regenerative motor in the power generation unit 20 keeps rotating at all times, there is no loss due to inertia and power generation performance is improved. Since the working fluid also flows through the second control valve 1N, the resistance of the knee joint 1 may be adjusted by adjusting the second control valve 1N.

[0082] As shown in FIG. 11, according to the fluid circuit 1S, when the extension motion of the knee joint 1 is decelerated or stopped, an idling circuit is formed in which the working fluid circulates through the power generation section 20.

[0083] The idling circuit is formed by a flow path connecting the power generating unit 20, the third check valve 1H2, and the first control valve 1M.

[0084] By circulating the working fluid in the idling circuit, the regenerative motor of the power generation unit 20 is not braked and power generation continues in the power generation unit 20. In the power generation unit 20, the regenerative motor of the power generation unit 20 keeps rotating at all times, so there is no loss due to inertia and the power generation performance is improved.

[0085] According to the fluid circuit 1S, when bending, the second control valve 1N acts as a series control valve for the power generation section 20, and the first control valve 1M acts as a parallel control valve for the power generation section 20. When extending, the first control valve 1M acts as a series control valve for the power generation section 20, and the second control valve 1N acts as a parallel control valve for the power generation section 20. In other words, the fluid circuit 1S acts as a circuit configuration similar to that of the fluid circuit 1Q of the second embodiment (see FIGS. 5 and 6).

[0086] According to the knee joint 1 of the third embodiment, the working fluid that flows based on the resistance generated during extension or flexion can be caused to flow in a fixed direction in the power generation unit 20, thereby reducing losses in the power generation unit 20 and improving power generation efficiency.

[0087] [Fourth embodiment] As shown in FIG. 12, the fluid circuit 1T according to the fourth embodiment is formed with a power generation flow path through which a working fluid flows. The power generation flow path includes an intermediate flow path 1TC in which a power generation section 20 is provided. A first flow path 1T1 and a second flow path 1T2 connected to the second port 1C12 are connected in parallel to a connection part 21 on one end side of the intermediate flow path 1TC. A third flow path 1T3 and a fourth flow path 1T4 connected to the first port 1C11 are connected in parallel to a connection part 22 on the other end side of the intermediate flow path 1TC. The connection part 21 on one end side of the intermediate flow path 1TC and the connection part 22 on the other end side are connected by a bypass flow path 1TB.

[0088] The first flow passage 1T1 is provided with a first control valve 1M for adjusting the flow rate of the working fluid. The second flow passage 1T2 is provided with a third check valve 1G3 for allowing the working fluid to flow from the intermediate flow passage 1TC to the second port 1C12 and restricting the flow of the working fluid from the second port 1C12 to the intermediate flow passage 1TC. The third flow passage 1T3 is provided with a second control valve 1N for adjusting the flow rate of the working fluid. The fourth flow passage 1T4 is provided with a fourth check valve 1H3 for allowing the working fluid to flow from the intermediate flow passage 1TC to the first port and restricting the flow of the working fluid from the first port 1C11 to the intermediate flow passage 1TC. The bypass flow passage 1TB is provided with a bypass control valve 1P for adjusting the flow rate of the working fluid flowing through the bypass flow passage 1TB. The bypass control valve 1P acts as a parallel control valve for the intermediate flow passage 1TC of the power generation unit 20.

[0089] During bending of the knee joint 1, the working fluid in the fluid circuit 1T is discharged from the second port 1C12, flows through the first control valve 1M, the power generation unit 20, and the fourth check valve 1H3, and returns to the first port 1C11. According to the fluid circuit 1T, during bending, the resistance of the knee joint 1 can be adjusted by controlling the first control valve 1M, and power can be generated in the power generation unit 20. At this time, the working fluid also flows through the second control valve 1N, so the resistance of the knee joint 1 can be adjusted by adjusting the second control valve 1N. When the bypass control valve 1P is opened during bending of the knee joint 1, the working fluid flows through the bypass flow path 1TB without passing through the power generation unit 20, and flows into the first port 1C11 via the fourth check valve 1H3, so no resistance is generated.

[0090] In the fluid circuit 1T, the bypass control valve 1P acts in the same manner as the extension side valve 1G in the fluid circuit 1Q of the second embodiment during extension, and acts in the same manner as the bending side valve 1H in the fluid circuit 1Q of the second embodiment during bending.

[0091] In the fluid circuit 1T, because the fourth check valve 1H3 is connected in parallel to the second control valve 1N, if the resistance of the fourth check valve 1H3 when the knee joint 1 is flexed is set to 0, the working fluid flows through the fourth flow path 1T4 regardless of the open / close state of the second control valve 1N, so the resistance of the entire fluid circuit 1T does not change. The knee joint 1 to which the fluid circuit 1T according to the fourth embodiment is applied can be configured so that the flexion-side resistance when flexing does not depend on the open / close state of the second control valve 1N for adjusting the extension-side resistance.

[0092] During extension of the knee joint 1, the working fluid is discharged from the first port 1C11 in the fluid circuit 1T, flows through the second control valve 1N, the power generation unit 20, and the third check valve 1G3, and returns to the second port 1C12. According to the fluid circuit 1T, during extension, the resistance of the knee joint 1 can be adjusted by controlling the second control valve 1N, and power can be generated in the power generation unit 20. At this time, the working fluid also flows through the first control valve 1M, so the resistance of the knee joint 1 may be adjusted by adjusting the first control valve 1M. When the bypass control valve 1P is opened during extension, the working fluid flows through the bypass flow path 1TB without passing through the power generation unit 20, and flows into the second port 1C12 via the third check valve 1G3, so no resistance is generated. In the fluid circuit 1T, the overall resistance in the fluid circuit 1T does not change even if the first control valve 1M is opened or closed.

[0093] The bypass control valve 1P is exemplified as a control valve whose opening and closing is controlled by a motor, but is not limited thereto. The bypass control valve 1P may be a bypass relief valve that is configured to automatically change from a closed state to an open state to allow the working fluid to flow when the pressure of the working fluid reaches or exceeds a predetermined constant pressure.

[0094] With the knee joint 1 according to the fourth embodiment, power can be generated in the power generation unit 20 based on the working fluid that flows based on the resistance generated during extension or bending, and further, since the working fluid flows through the first control valve during extension and through the second control valve during bending, the resistance can be adjusted as desired. With the knee joint 1, the generated resistance can also be eliminated by opening the bypass control valve 1P that acts as a parallel control valve in the bypass flow path 1TB.

[0095] With the knee joint 1, the working fluid flows through the first control valve during extension and through the second control valve during bending, so that the resistance can be adjusted independently (arbitrarily) for bending and extension. Furthermore, with the knee joint 1, the resistance generated can be eliminated by opening the parallel control valve of the bypass flow path. According to the present invention, it is possible to generate either a weaker or stronger resistance than the resistance generated in the power generation section.

[0096] The above-mentioned control unit 1E is realized by a processor such as a central processing unit (CPU) or a graphics processing unit (GPU) executing a program (software). Some or all of these functional units may be realized by hardware such as a large scale integration (LSI), an application specific integrated circuit (ASIC), or a field programmable gate array (FPGA), or may be realized by a combination of software and hardware. The program may be stored in a storage device such as a hard disk drive (HDD) or a flash memory in advance, or may be stored in a removable storage medium such as a DVD or a CD-ROM, and installed in the storage device by mounting the storage medium in a drive device.

[0097] The present invention is not limited to the above-described embodiment, and includes various modifications of the above-described embodiment without departing from the spirit of the present invention. In the above-described embodiment, the power generating unit generates power using a gear motor. The power generating unit is not limited to this, and other power generating devices may be applied. For example, the power generating unit may be a linear motor that generates power in response to an expanding and contracting mechanism such as a cylinder in the knee joint, or a regenerative motor provided on the rotating shaft of the knee joint. In addition, a rack may be formed on the piston rod, and the expansion and contraction of the rack may be converted into rotation by a pinion gear and connected to a gear motor to generate power.

[0098] In each of the above-mentioned embodiments, if a plurality of objects are included, the plurality of objects may be integrated, and conversely, if a single object is included, the plurality of objects may be separated. Regardless of whether the objects are integrated or not, it is sufficient that the object of the invention can be achieved.

[0099] In each of the above-mentioned embodiments, in the case where a plurality of functions are provided in a distributed manner, some or all of the functions may be provided in an integrated manner, and conversely, in the case where a plurality of functions are provided in an integrated manner, some or all of the functions may be provided in a distributed manner. Regardless of whether the functions are integrated or distributed, it is sufficient that the configuration can achieve the object of the invention. [Explanation of symbols]

[0100] 1...knee joint, 1A...thigh connection part, 1B...lower leg part, 1C...cylinder, 1C1...cylinder tube, 1C11...first port, 1C12...second port, 1C13...connection part, 1C2...piston, 1C3...piston rod, 1CF...lid, 1CH...through hole, 1D...detection part, 1E...control part, 1G...extension side valve, 1G1...extension side check valve, 1G2...fourth check valve, 1G3...third check valve, 1H...flexion side valve, 1H1...flexion side check valve, 1H2...third check valve, 1H3...fourth check valve, 1J...battery, 1K...battery status acquisition part, 1 M...first control valve, 1N...second control valve, 1P...bypass control valve, 1Q...fluid circuit, 1Q1...flow path, 1Q2...flow path, 1Q3...flow path, 1S...fluid circuit, 1S1...first flow path, 1S2...second flow path, 1S3...third flow path, 1S4...fourth flow path, 1SC...middle flow path, 1T...fluid circuit, 1T1...first flow path, 1T2...second flow path, 1T3...third flow path, 1T4...fourth flow path, 1TB...bypass flow path, 1TC...middle flow path, 2...theoretically, 10...control device, 11...front link section, 12...rear link section, 13...first shaft, 14...second shaft, 20...power generation section

Claims

1. A thigh connection portion provided on the thigh side; A lower leg portion rotatably connected to the thigh connection portion; A power generating unit that generates power using resistance generated when the lower leg portion rotates relative to the thigh connection portion; a fluid circuit having a control valve through which a working fluid flows to generate the resistance and which adjusts the resistance based on the flow of the working fluid; a control unit that controls an operation of the control valve and operates using the electric power generated by the power generation unit; Equipped with the fluid circuit includes a fluid pressure cylinder operated by the working fluid, and a power generation flow path that connects a first port and a second port in the fluid pressure cylinder, the first port and the second port being partitioned by a piston that moves within the fluid pressure cylinder, and in which the power generation unit is provided, the power generation flow path includes a first parallel flow path including a first parallel control valve for adjusting a flow rate of the working fluid through the first parallel flow path from the first port to the second port; a second parallel flow passage including a second parallel control valve through which the working fluid flows from the second port to the first port and which adjusts a flow rate of the working fluid; a power generation section flow path provided in the power generation flow path and having the power generation section; Equipped with the first parallel flow path, the second parallel flow path, and the power generation section flow path are provided in parallel, the power generation section flow passage has a power generation section control valve connected in series with the power generation section and configured to adjust the flow rate of the working fluid flowing through the power generation section flow passage, the control unit independently controls the first parallel control valve or the second parallel control valve to adjust the flow rate of the working fluid in a flow direction to the power generation unit. Knee joint.

2. The knee joint according to claim 1 , wherein the power generating unit includes a gear motor that is driven by the working fluid to generate electricity.

3. a control valve provided in the power generation flow path and controlling a relationship between a flow rate of the working fluid flowing through the power generation flow path and a differential pressure generated by a pressure loss; A knee joint according to claim 1 or 2.

4. the power generation flow path includes another flow path connecting the first port and the second port, Another control valve is provided in the other flow path to control the relationship between the flow rate of the working fluid flowing therethrough and the differential pressure caused by pressure loss. The knee joint according to claim 3.

5. a first check valve that limits the flow of the working fluid from the second port to the first port in the first parallel flow passage; a second check valve that limits the flow of the working fluid from the first port to the second port in the second parallel flow path. A knee joint according to claim 1 or 2.

6. A thigh connection portion provided on the thigh side; A lower leg portion rotatably connected to the thigh connection portion; A power generating unit that generates power using resistance generated when the lower leg portion rotates relative to the thigh connection portion; a fluid circuit having a control valve through which a working fluid flows to generate the resistance and which adjusts the resistance based on the flow of the working fluid; a control unit that controls an operation of the control valve and operates using the electric power generated by the power generation unit; Equipped with the fluid circuit includes a fluid pressure cylinder operated by the working fluid, and a power generation flow path that connects a first port and a second port in the fluid pressure cylinder, the first port and the second port being partitioned by a piston that moves within the fluid pressure cylinder, and in which the power generation unit is provided, the power generation flow path includes a first flow path connecting one end side of an intermediate flow path in which the power generation unit is provided and the first port; a second flow passage connecting the one end side of the intermediate flow passage and the second port; a third flow passage connecting the other end of the intermediate flow passage and the first port; a fourth flow passage connecting the other end side of the intermediate flow passage and the second port, A first control valve that adjusts a flow rate of the working fluid is provided in the first flow path, A second control valve that adjusts the flow rate of the working fluid is provided in the second flow path, a third check valve is provided in the third flow path to limit the flow of the working fluid in a flow direction from the first port to the intermediate flow path and to allow the flow of the working fluid in a flow direction from the intermediate flow path to the first port, a fourth check valve is provided in the fourth flow passage to limit movement of the working fluid in a flow direction from the second port to the intermediate flow passage and to allow flow of the working fluid in a flow direction from the intermediate flow passage to the second port; Knee joint.

7. the power generation flow path includes a first flow path and a second flow path that connect in parallel one end side of an intermediate flow path in which the power generation unit is provided and the second port, and a third flow path and a fourth flow path that connect in parallel the other end side of the intermediate flow path and the first port, A first control valve that adjusts a flow rate of the working fluid is provided in the first flow path, a second control valve that adjusts a flow rate of the working fluid is provided in the third flow path; a third check valve is provided in the second flow passage to allow the working fluid to flow from the intermediate flow passage to the second port and to restrict the working fluid to flow from the second port to the intermediate flow passage; a fourth check valve is provided in the fourth flow passage to allow the working fluid to flow from the intermediate flow passage to the first port and to restrict the working fluid to flow from the first port to the intermediate flow passage; The knee joint of claim 1.

8. a bypass flow path connecting the one end side and the other end side of the intermediate flow path; 8. The knee joint according to claim 7, further comprising: a bypass control valve or a bypass relief valve provided in the bypass flow path to adjust a flow rate of the working fluid flowing through the bypass flow path.

9. a control unit that controls an operation of the control valve and operates using the electric power generated by the power generation unit, The control unit arbitrarily adjusts the other control valve when a resistance weaker than the power generation resistance generated by the power generation unit is generated, and arbitrarily adjusts the control valve when a resistance stronger than the power generation resistance is generated.

5. The knee joint of claim 4.

10. A thigh connection portion provided on the thigh side; A lower leg portion rotatably connected to the thigh connection portion; A power generating unit that generates power using resistance generated when the lower leg portion rotates relative to the thigh connection portion; a fluid circuit in which the power generating unit is provided and through which a working fluid that generates the resistance flows; a control valve provided in the fluid circuit and adjusting the resistance based on the flow of the working fluid; a control unit that controls an operation of the control valve and operates using the electric power generated by the power generation unit; a fluid pressure cylinder provided in the fluid circuit and operated by the working fluid; a power generation flow path that connects a first port and a second port in the fluid pressure cylinder, the first port and the second port being partitioned by a piston that moves in the fluid pressure cylinder, and in which the power generation unit is provided, the power generation flow path includes a first flow path connecting one end side of an intermediate flow path in which the power generation unit is provided and the first port; a second flow passage connecting the one end side of the intermediate flow passage and the second port; a third flow passage connecting the other end of the intermediate flow passage and the first port; a fourth flow passage connecting the other end side of the intermediate flow passage and the second port, A first control valve that adjusts a flow rate of the working fluid is provided in the first flow path, A second control valve that adjusts the flow rate of the working fluid is provided in the second flow path, a third check valve is provided in the third flow path to limit the flow of the working fluid in a flow direction from the first port to the intermediate flow path and to allow the flow of the working fluid in a flow direction from the intermediate flow path to the first port, a fourth check valve is provided in the fourth flow passage to limit movement of the working fluid in a flow direction from the second port to the intermediate flow passage and to allow flow of the working fluid in a flow direction from the intermediate flow passage to the second port; Knee joint.

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