A double-cylinder cooperative heat-dissipation hydraulic foot and ankle prosthesis

Abstract

The present application belongs to the technical field of human body artificial limb, especially to a double-cylinder cooperative heat-dissipation hydraulic foot and ankle prosthesis, which comprises an elastic foot plate, a ankle joint connecting seat is fixedly arranged on the elastic foot plate, the ankle joint connecting seat is rotationally connected with an ankle joint support seat through a rotating shaft, and a main hydraulic cylinder is fixedly arranged on the ankle joint support seat. The double-mode heat-dissipation mode of the alternating work and the isolated heat-dissipation of the two auxiliary hydraulic cylinders can effectively improve the oil heat-dissipation effect without additional consumption of a large amount of electric energy, and can relieve the problems of the oil heat accumulation and the damping performance attenuation of the traditional closed hydraulic prosthesis. Meanwhile, the hydraulic pressure is used to drive the connecting rod to realize the passive power assistance synchronized with the gait, and the spring telescopic rod, the elastic limiting strip and the hydraulic damping are cooperatively matched to provide the axial shock absorption and the ankle joint rotation buffering.

Description

Technical Field

[0001] This invention belongs to the field of human prosthetics technology, and in particular relates to a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis. Background Technology

[0002] Currently, the foot and ankle prostheses commonly used by lower limb amputees are mainly divided into rigid prostheses and hydraulically damped prostheses. Among them, hydraulically damped foot and ankle prostheses, through the cooperation of hydraulic cylinders and elastic foot plates, can provide cushioning and shock absorption during walking, adapt to the ankle joint rotation needs of normal human gait, improve the patient's wearing comfort and walking ability, and are the mainstream products in the current civilian rehabilitation prosthesis field.

[0003] However, hydraulically damped ankle prostheses all use closed hydraulic circuits. The hydraulic oil is continuously subjected to shearing and compression within the cylinder, constantly generating heat and gradually accumulating. Due to the fixed structure of the hydraulic circuit, the hydraulic oil can only flow along a single fixed path and is always in a state of generating heat while passively dissipating heat through the cylinder wall. The overall cooling efficiency is low. After long-term use, the increased oil temperature will cause the hydraulic oil viscosity to decrease and the damping performance to continuously deteriorate, thereby affecting the shock absorption stability of the prosthesis and shortening the service life of the hydraulic oil and seals. In addition, a few heat dissipation solutions use active heat dissipation structures such as semiconductor cooling and fan cooling. Although these can improve the heat dissipation effect, they require a large amount of electrical energy to be consumed continuously. Since the battery capacity of the prosthesis is limited, cooling through a high-power cooling structure will significantly reduce the prosthesis's range.

[0004] To address the above problems, this invention provides a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a dual-cylinder alternating cooling hydraulic damping foot and ankle prosthesis to solve the problems of low heat dissipation efficiency of the closed hydraulic circuit, easy accumulation of oil heat, damping performance degradation caused by oil temperature rise, high power consumption and limited endurance of the active cooling structure in the prior art.

[0006] To achieve the above and other related objectives, the present invention adopts the following technical solution: a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, comprising an elastic footplate, an ankle joint connecting seat fixedly mounted on the elastic footplate, and an ankle joint support seat rotatably connected to the ankle joint connecting seat via a rotating shaft, a main hydraulic cylinder fixedly mounted on the ankle joint support seat, and a main piston slidably mounted in the main hydraulic cylinder, the lower side of the main piston being fixedly connected to the inner bottom surface of the main hydraulic cylinder via multiple spring telescopic rods, and a support rod fixedly mounted on the upper side of the main piston, the upper end of the support rod extending to the outside of the main hydraulic cylinder and fixedly connected to a lower leg connecting seat, a hydraulically assisted cooling unit fixedly mounted on the main hydraulic cylinder, and connecting rods hinged to both the front and rear ends of the elastic footplate, with the ends of the two connecting rods away from the elastic footplate respectively hinged to the two output ends of the hydraulically assisted cooling unit.

[0007] In the aforementioned dual-cylinder synergistic cooling hydraulic ankle prosthesis, the spring telescopic rod includes an inner sleeve, an outer sleeve, and a shock-absorbing spring. The outer sleeve is slidably connected to the inner sleeve, and the outer sleeve and the inner sleeve are fixedly connected by the shock-absorbing spring. The inner sleeve is fixedly installed on the inner bottom surface of the main hydraulic cylinder, and the upper end of the outer sleeve is fixedly connected to the main piston.

[0008] In the aforementioned dual-cylinder synergistic cooling hydraulic ankle prosthesis, the hydraulic-assisted cooling unit includes two auxiliary hydraulic cylinders, two auxiliary pistons, and two auxiliary piston rods. The two auxiliary hydraulic cylinders are respectively fixedly mounted on the left and right sides of the main hydraulic cylinder, and the two auxiliary pistons are respectively slidably connected to their corresponding auxiliary hydraulic cylinders. Both the main hydraulic cylinder and the two auxiliary hydraulic cylinders are filled with oil. The two auxiliary piston rods are respectively fixedly connected to their corresponding auxiliary pistons, and the lower ends of both auxiliary piston rods extend to the outside of the auxiliary hydraulic cylinder and are hinged to their corresponding connecting rods. The main hydraulic cylinder… The upper and lower chambers of the pressure cylinder are each fixedly connected to two fluid guide pipes. The two fluid guide pipes on the upper side of the main hydraulic cylinder are fixedly connected to the upper chamber of the left auxiliary hydraulic cylinder and the lower chamber of the right auxiliary hydraulic cylinder, respectively. The two fluid guide pipes on the lower side of the main hydraulic cylinder are fixedly connected to the lower chamber of the left auxiliary hydraulic cylinder and the upper chamber of the right auxiliary hydraulic cylinder, respectively. Each of the four fluid guide pipes is equipped with a fluid guide solenoid valve and an electrically controlled throttle valve. A PLC controller is fixedly installed inside the ankle joint support seat, and the PLC controller is electrically connected to each fluid guide solenoid valve and the electrically controlled throttle valve.

[0009] In the aforementioned dual-cylinder synergistic cooling hydraulic ankle prosthesis, the upper and lower chambers of the auxiliary hydraulic cylinder are connected by a connecting pipe, and a follow-up solenoid valve is installed on the connecting pipe. The follow-up solenoid valve is electrically connected to the PLC controller.

[0010] In the aforementioned dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, temperature sensors are fixedly installed on the lower side of the left auxiliary hydraulic cylinder and the upper side of the right auxiliary hydraulic cylinder, and the detection end of the temperature sensor extends into the corresponding chamber of the auxiliary hydraulic cylinder. Both temperature sensors are electrically connected to the PLC controller.

[0011] In the aforementioned dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, several pressure sensors are fixedly arranged on the lower end face of the elastic foot plate, and an angle sensor that cooperates with the rotating shaft is fixedly installed on the ankle joint connecting seat. Each of the pressure sensors and angle sensors is electrically connected to the PLC controller.

[0012] In the aforementioned dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, an elastic limiting strip is fixedly provided between the elastic foot plate and the ankle joint support seat. The elastic limiting strip is used to provide flexible limiting for the ankle joint support seat and the ankle joint connecting seat.

[0013] In the aforementioned dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, several heat dissipation fins are fixedly arranged on the main hydraulic cylinder and the two auxiliary hydraulic cylinders. The heat dissipation fins are used to assist the main hydraulic cylinder and the two auxiliary hydraulic cylinders in dissipating heat.

[0014] Compared with existing technologies, the advantages of a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis are:

[0015] 1. By setting up a dual-mode alternating hydraulic circuit with the main hydraulic cylinder and two auxiliary hydraulic cylinders working in coordination, combined with the coordinated control of the guide solenoid valve, the electronically controlled throttle valve, the temperature sensor, and the PLC controller, the two auxiliary hydraulic cylinders alternately connect to the main circuit. When one is in working cooling mode, the other is in isolation cooling mode. In working cooling mode, the oil participates in the circulation of the main circuit and is cooled in real time through the heat sink. In isolation cooling mode, the oil is completely isolated from the main hydraulic cylinder's oil circuit and forms a low-pressure slow-flow circulation in the cylinder as the ankle joint rotates. It is then centrally cooled by the heat sink. After switching, the cooled oil mixes with the hot oil in the main circuit to achieve gradient cooling, avoiding the accumulation of heat due to continuous high-load shearing and compression of the hydraulic oil. This solution does not require high-power active cooling structures such as semiconductor refrigeration and fans. It not only alleviates the problem of damping performance degradation and shortened service life of hydraulic oil and seals caused by oil temperature rise in traditional closed hydraulic circuits, but also does not consume a large amount of additional electrical energy, effectively ensuring the prosthesis's endurance.

[0016] 2. By setting up a gait synchronization hydraulic transmission structure that works in conjunction with the connecting rods and auxiliary piston rods that are hinged to the front and rear ends of the elastic footplate, combined with gait phase recognition by the plantar pressure sensor and ankle joint angle sensor and damping adaptive adjustment by the electronically controlled throttle valve, during the heel strike dorsiflexion and push-off plantarflexion phases, the body's gravity compresses the hydraulic fluid through the main piston, driving the corresponding auxiliary piston to move, which in turn drives the connecting rod to provide an auxiliary torque to the elastic footplate in the same direction as the gait movement, converting gravitational potential energy into passive assistance and improving walking efficiency. At the same time, the PLC controller can adjust the hydraulic damping in real time according to different working conditions such as walking and running, taking into account both the wearing comfort of daily walking and the support stability during strenuous exercise.

[0017] 3. By setting up a multi-stage buffer structure formed by the coordinated action of spring telescopic rods, elastic limiting strips, and hydraulic damping, the spring telescopic rods can constrain the shock-absorbing springs to extend and retract axially. The axial deformation of the shock-absorbing springs absorbs vertical impact loads and works in conjunction with hydraulic damping to achieve axial shock absorption. The hydraulic damping can suppress secondary impacts caused by excessively rapid rebound of the shock-absorbing springs, while providing flexible damping for ankle joint rotation. Combined with the progressive flexible limiting of the elastic limiting strips, this achieves buffering and shock absorption at the ankle joint rotation point, which not only avoids damage caused by excessive ankle joint rotation but also improves the smoothness of ankle joint rotation, effectively enhancing the wearing comfort of the prosthesis. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis provided by the present invention;

[0019] Figure 2 This is a schematic diagram of the right side of a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis provided by the present invention;

[0020] Figure 3 This is a frontal perspective view of the main hydraulic cylinder and two auxiliary hydraulic cylinders cooperating with each other in a dual-cylinder collaborative heat dissipation hydraulic foot and ankle prosthesis provided by the present invention.

[0021] Figure 4 This is a cross-sectional structural schematic diagram of the spring telescopic rod of a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis provided by the present invention.

[0022] In the diagram: 1. Elastic footplate, 2. Ankle joint connector, 3. Rotary shaft, 4. Ankle joint support, 5. Main hydraulic cylinder, 6. Main piston, 7. Spring telescopic rod, 71. Inner sleeve, 72. Outer sleeve, 73. Shock-absorbing spring, 8. Support rod, 9. Lower leg connector, 10. Hydraulic power-assisted cooling unit, 101. Secondary hydraulic cylinder, 102. Secondary piston, 103. Secondary piston rod, 11. Connecting rod, 12. Liquid guide tube, 13. Liquid guide solenoid valve, 14. Electrically controlled throttle valve, 15. Connecting pipe, 16. Follow-up solenoid valve, 17. Temperature sensor, 18. Elastic limit strip, 19. Heat sink. Detailed Implementation

[0023] Specific embodiments of the present invention will now be described in detail. It should be noted that the embodiments described herein are for illustrative purposes only and are not intended to limit the invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other instances, well-known circuits, software, or methods have not been specifically described to avoid obscuring the invention.

[0024] like Figures 1-4 As shown, a dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis includes an elastic foot plate 1, an ankle joint connecting seat 2 fixedly mounted on the elastic foot plate 1, and an ankle joint support seat 4 rotatably connected to the ankle joint connecting seat 2 via a rotating shaft 3. A main hydraulic cylinder 5 is fixedly mounted on the ankle joint support seat 4, and a main piston 6 is slidably and sealed in the main hydraulic cylinder 5. The lower side of the main piston 6 is fixedly connected to the inner bottom surface of the main hydraulic cylinder 5 via multiple spring telescopic rods 7, and a support rod 8 is fixedly mounted on the upper side of the main piston 6. The upper end of the support rod 8 extends to the outside of the main hydraulic cylinder 5 and is fixedly connected to a lower leg connecting seat 9.

[0025] The spring telescopic rod 7 includes an inner sleeve 71, an outer sleeve 72, and a shock-absorbing spring 73. The outer sleeve 72 is slidably connected to the inner sleeve 71, and the outer sleeve 72 and the inner sleeve 71 are fixedly connected by the shock-absorbing spring 73. The inner sleeve 71 is fixedly installed on the inner bottom surface of the main hydraulic cylinder 5, and the upper end of the outer sleeve 72 is fixedly connected to the main piston 6. Through the cooperation of the inner sleeve 71 and the outer sleeve 72, the shock-absorbing spring 73 is constrained to extend and retract axially. The axial deformation of the shock-absorbing spring 73 absorbs the impact load and works in conjunction with the hydraulic damping to achieve axial buffering and shock absorption.

[0026] A hydraulic assist cooling unit 10 is fixedly installed on the main hydraulic cylinder 5 and cooperates with it. The front and rear ends of the elastic foot plate 1 are both hinged with connecting rods 11, and the ends of the two connecting rods 11 away from the elastic foot plate 1 are respectively hinged to the two output ends of the hydraulic assist cooling unit 10.

[0027] The hydraulic-assisted cooling unit 10 includes two auxiliary hydraulic cylinders 101, two auxiliary pistons 102, and two auxiliary piston rods 103. The two auxiliary hydraulic cylinders 101 are fixedly mounted on the left and right sides of the main hydraulic cylinder 5, respectively, and the two auxiliary pistons 102 are respectively slidably connected to their corresponding auxiliary hydraulic cylinders 101. The main hydraulic cylinder 5 and the two auxiliary hydraulic cylinders 101 are filled with oil. Several heat sinks 19 are fixedly arranged on the main hydraulic cylinder 5 and the two auxiliary hydraulic cylinders 101 to assist in the cooling of the main hydraulic cylinder 5 and the two auxiliary hydraulic cylinders 101. The two auxiliary piston rods 103 are respectively fixedly connected to their corresponding auxiliary pistons 102, and the lower ends of the two auxiliary piston rods 103 extend to the outside of the auxiliary hydraulic cylinder 101 and are hinged to their corresponding connecting rods 11. The upper and lower chambers of the main hydraulic cylinder 5 are fixedly connected to two liquid guide pipes 12. The two liquid guide pipes 12 on the upper side of the main hydraulic cylinder 5 are respectively connected to the upper chamber of the left auxiliary hydraulic cylinder 101. The main hydraulic cylinder 5 has a fixed connection between the lower chamber of the main hydraulic cylinder 5 and the lower chamber of the right auxiliary hydraulic cylinder 101. The two liquid guide pipes 12 on the lower side of the main hydraulic cylinder 5 are fixedly connected to the lower chamber of the left auxiliary hydraulic cylinder 101 and the upper chamber of the right auxiliary hydraulic cylinder 101, respectively. Each of the four liquid guide pipes 12 is equipped with a liquid guide solenoid valve 13 and an electrically controlled throttle valve 14. A PLC controller is fixedly installed inside the ankle joint support 4, and the PLC controller is electrically connected to each liquid guide solenoid valve 13 and the electrically controlled throttle valve 14. At the same time, a battery is also installed inside the ankle joint support 4 to power the prosthesis. Through the cooperation of the two auxiliary hydraulic cylinders 101 with the liquid guide pipes 12, the liquid guide solenoid valves 13, the electrically controlled throttle valves 14 and the PLC controller, the two auxiliary hydraulic cylinders 101 are alternately connected to the circuit of the main hydraulic cylinder 5. When one is working, the other is isolated for heat dissipation, realizing dual-mode coordinated heat dissipation. At the same time, the auxiliary piston rod 103 drives the connecting rod 11 to provide passive assistance in coordination with the gait.

[0028] Temperature sensors 17 are fixedly installed on the lower side of the left auxiliary hydraulic cylinder 101 and the upper side of the right auxiliary hydraulic cylinder 101. The detection end of the temperature sensor 17 extends into the chamber of the corresponding auxiliary hydraulic cylinder 101. Both temperature sensors 17 are electrically connected to the PLC controller. The temperature sensors 17 are used to monitor the oil temperature of the two auxiliary hydraulic cylinders 101 in the working heat dissipation mode, providing a basis for the PLC controller to determine whether the heat dissipation mode needs to be switched.

[0029] Several pressure sensors are fixedly arranged on the lower end face of the elastic footplate 1, and an angle sensor that cooperates with the rotating shaft 3 is fixedly installed on the ankle joint connecting seat 2. Each pressure sensor and angle sensor is electrically connected to the PLC controller. The PLC controller collects the plantar pressure distribution and ankle joint rotation angle in real time through the pressure sensors on the lower end face of the elastic footplate 1 and the angle sensor at the rotating shaft 3. Based on this, it identifies the current gait phase and walking condition. In terms of gait phase, when only the heel area detects ground contact pressure and the angle sensor shows that the ankle joint begins to dorsiflex, it is determined to be heel strike. When there is pressure distribution on both the heel and the forefoot, it is full foot strike. When the heel pressure disappears and only the forefoot and toes have pressure and the ankle joint... When the ankle begins to flex, it is determined to be the push-off phase. When all pressure signals disappear, it is the swing phase. In terms of walking conditions, the PLC controller makes a comprehensive judgment based on the characteristic parameters of multiple consecutive gait cycles. When the gait cycle is longer, the peak pressure of the foot is relatively lower, and the change in the ankle joint angle is gentle, it is identified as walking. When the gait cycle is significantly shortened, the peak pressure is significantly increased, and the rate of change in the angle is accelerated, it is identified as running. Based on the above recognition results, the PLC controller adaptively adjusts the opening of the electronically controlled throttle valve 14. When walking, the opening is increased to reduce hydraulic damping and improve the flexibility of ankle joint rotation and wearing comfort. When running, the opening is decreased to increase hydraulic damping and provide stronger support stability and impact absorption capacity.

[0030] The upper and lower chambers of the auxiliary hydraulic cylinder 101 are connected by a connecting pipe 15, and a follow-up solenoid valve 16 is provided on the connecting pipe 15. The follow-up solenoid valve 16 is electrically connected to the PLC controller. When the auxiliary hydraulic cylinder 101 is in the isolation and heat dissipation mode, the follow-up solenoid valve 16 is opened to short-circuit its upper and lower chambers, so that the oil can circulate between the upper and lower chambers, thus preventing the movement of the auxiliary piston 102 in the isolation state from being restricted, thereby restricting the rotation of the ankle joint.

[0031] An elastic limiting strip 18 is fixedly installed between the elastic footplate 1 and the ankle joint support seat 4. The elastic limiting strip 18 is used to provide flexible limiting for the ankle joint support seat 4 and the ankle joint connecting seat 2. Through the elastic limiting strip 18, progressive elastic resistance is provided when the ankle joint rotates, enhancing the smoothness of rotation within the normal gait range, and providing buffering and stopping at the extreme angle to prevent excessive rotation of the ankle joint. At the same time, it works in conjunction with the hydraulic damping generated by the hydraulic oil flow in the auxiliary hydraulic cylinders 101 on both sides to achieve buffering and shock absorption at the ankle joint rotation.

[0032] The operating principle of the present invention is now described as follows:

[0033] In the initial state, taking the left auxiliary hydraulic cylinder 101 in the hydraulic power cooling unit 10 as being in working cooling mode and the right auxiliary hydraulic cylinder 101 in isolation cooling mode as an example, the PLC controller controls the solenoid valves 13 on the two liquid guide pipes 12 on the left to open, so that the left auxiliary hydraulic cylinder 101 is connected to the hydraulic circuit of the main hydraulic cylinder 5, and controls the solenoid valves 13 on the two liquid guide pipes 12 on the right to close, so that the right auxiliary hydraulic cylinder 101 is isolated from the oil circuit of the main hydraulic cylinder 5. At the same time, the follow-up solenoid valve 16 on the right connecting pipe 15 is opened, so that the upper and lower chambers of the right auxiliary hydraulic cylinder 101 are connected.

[0034] When the patient enters the heel-to-spot dorsiflexion stage of walking, the body weight acts on the main piston 6 through the lower leg connecting seat 9 and the support rod 8. The main piston 6 moves downward, and the shock-absorbing spring 73 in the spring telescopic rod 7 is compressed under the guidance of the outer sleeve 72 along the inner sleeve 71, absorbing the vertical impact load and storing elastic potential energy. At the same time, the oil in the lower chamber of the main hydraulic cylinder 5 is pressurized and enters the lower chamber of the left auxiliary hydraulic cylinder 101 through the lower left guide pipe 12, pushing the left auxiliary piston 102 to move upward. The oil in the upper chamber of the left auxiliary hydraulic cylinder 101 flows into the upper chamber of the main hydraulic cylinder 5 through the upper left guide pipe 12. When the oil flows through each electronically controlled throttle valve 14, the throttle damping and the elastic buffer of the shock-absorbing spring 73 work together to achieve axial shock absorption.

[0035] When the left auxiliary piston 102 moves upward, the front end of the elastic foot plate 1 is lifted upward through the left auxiliary piston rod 103 and the left connecting rod 11. The lifting direction is consistent with the dorsiflexion movement direction of the front end of the elastic foot plate 1, which converts the gravitational potential energy of the human body into an auxiliary torque synchronized with the gait, providing passive dorsiflexion assistance.

[0036] When entering the plantar flexion phase, the vertical load acting on the support rod 8 gradually decreases, the damping spring 73 releases the stored elastic potential energy, and pushes the main piston 6 to return to its original position. When the main piston 6 moves upward, the volume of the lower chamber of the main hydraulic cylinder 5 increases, generating negative pressure, which draws the oil in the lower chamber of the left auxiliary hydraulic cylinder 101 back through the lower left guide pipe 12. At the same time, the oil in the upper chamber of the main hydraulic cylinder 5 is replenished into the upper chamber of the left auxiliary hydraulic cylinder 101 through the upper left guide pipe 12. The left auxiliary piston 102 moves downward, and pushes the front end of the elastic foot plate 1 downward through the left auxiliary piston rod 103 and the left connecting rod 11. The pushing direction is consistent with the plantar flexion direction, providing passive plantar flexion assistance. When the oil flows back, it flows through the electronically controlled throttle valve 14, whose throttle damping can suppress the damping spring 73 from rebounding too quickly and avoid secondary impact.

[0037] Throughout the entire process, the right auxiliary hydraulic cylinder 101 is always in an isolation and heat dissipation mode. It is completely isolated from the working oil circuit of the main hydraulic cylinder 5, but it is not statically closed. As the ankle joint rotates, the elastic foot plate 1 drives the right auxiliary piston 102 to make a slight reciprocating motion through the right connecting rod 11 and the right auxiliary piston rod 103. This causes the oil in the cylinder to form a low-pressure slow flow circulation between the upper and lower chambers through the opened connecting pipe 15. This process generates almost no shear heat, but makes the oil flow evenly through the cylinder wall and dissipate heat efficiently through the heat sink 19, forming a heat dissipation circuit dominated by cooling.

[0038] When the left temperature sensor 17 detects that the oil temperature has reached the preset upper limit, or when the continuous working time of the left auxiliary hydraulic cylinder 101 reaches the threshold, the PLC controller identifies the gait entering the oscillation period through the pressure sensor and angle sensor and executes the switching program. First, it opens the two right liquid guiding solenoid valves 13 and closes the right follow-up solenoid valve 16, so that the two auxiliary hydraulic cylinders 101 work in parallel for a preset transition time. Then, it closes the two left liquid guiding solenoid valves 13 and opens the left follow-up solenoid valve 16 to complete the switching. At this time, the right auxiliary hydraulic cylinder 101 switches to the working heat dissipation mode. The oil inside it is fully cooled and mixes with the hot oil in the main circuit to achieve a gradient and steady drop in oil temperature. The left auxiliary hydraulic cylinder 101 switches to the isolation heat dissipation mode. The two auxiliary hydraulic cylinders 101 switch cyclically according to this logic.

[0039] When the right auxiliary hydraulic cylinder 101 is working, since the corresponding guide pipe 12 is connected in the opposite direction to the left auxiliary hydraulic cylinder 101, during dorsiflexion, the main piston 6 presses down, and the oil in the lower chamber of the main hydraulic cylinder 5 enters the upper chamber of the right auxiliary hydraulic cylinder 101, pushing the right auxiliary piston 102 downward. Through the right connecting rod 11, it pushes the rear end of the elastic foot plate 1 downward, providing passive dorsiflexion assistance in conjunction with the downward pressing direction of the heel. During plantarflexion, the main piston 6 moves up to reset, and the oil in the upper chamber of the right auxiliary hydraulic cylinder 101 is drawn back. The oil in the upper chamber of the main hydraulic cylinder 5 is replenished into the lower chamber of the right auxiliary hydraulic cylinder 101, pushing the right auxiliary piston 102 upward. Through the right connecting rod 11, it lifts the rear end of the elastic foot plate 1 upward, providing passive plantarflexion assistance in conjunction with the lifting direction of the heel. The left and right auxiliary hydraulic cylinders 101 work alternately, respectively providing passive assistance to the front and rear ends of the elastic foot plate 1 for gait synchronization, realizing auxiliary output throughout the entire gait cycle.

[0040] During walking, the PLC controller collects the pressure distribution of the sole and the rotation angle of the ankle joint in real time through the pressure sensor on the elastic foot plate 1 and the angle sensor at the pivot 3. It identifies the current gait phase and walking condition. When it is identified as walking, it increases the opening of the electronically controlled throttle valve 14 to reduce damping and improve walking comfort. When it is identified as running, it decreases the opening of the electronically controlled throttle valve 14 to increase damping and improve support stability.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis, comprising an elastic footplate (1), characterized in that, An ankle joint connecting seat (2) is fixedly installed on the elastic foot plate (1), and the ankle joint connecting seat (2) is rotatably connected to the ankle joint support seat (4) through the rotating shaft (3). The ankle joint support seat (4) is fixedly installed on the main hydraulic cylinder (5), and the main piston (6) is sealed and slidably installed in the main hydraulic cylinder (5). The lower side of the main piston (6) is fixedly connected to the inner bottom surface of the main hydraulic cylinder (5) through multiple spring telescopic rods (7), and the upper side of the main piston (6) is fixedly installed on the support rod (8). The upper end of the support rod (8) extends to the outside of the main hydraulic cylinder (5) and is fixedly connected to the lower leg connecting seat (9). The main hydraulic cylinder (5) is fixedly installed with a hydraulic assist heat dissipation unit (10) that cooperates with it. The front and rear ends of the elastic foot plate (1) are both hinged with connecting rods (11), and the ends of the two connecting rods (11) away from the elastic foot plate (1) are respectively hinged to the two output ends of the hydraulic assist heat dissipation unit (10). The hydraulic power-assisted cooling unit (10) includes two auxiliary hydraulic cylinders (101), two auxiliary pistons (102), and two auxiliary piston rods (103). The two auxiliary hydraulic cylinders (101) are fixedly disposed on the left and right sides of the main hydraulic cylinder (5), and the two auxiliary pistons (102) are respectively sealed and slidably connected to the corresponding auxiliary hydraulic cylinders (101). The main hydraulic cylinder (5) and the two auxiliary hydraulic cylinders (101) are filled with oil. The two auxiliary piston rods (103) are respectively fixedly connected to the corresponding auxiliary pistons (102), and the lower ends of the two auxiliary piston rods (103) extend to the outside of the auxiliary hydraulic cylinder (101) and are hinged to the corresponding connecting rods (11). The upper part of the main hydraulic cylinder (5) The two lower chambers are fixedly connected to two liquid guide pipes (12). The two liquid guide pipes (12) on the upper side of the main hydraulic cylinder (5) are fixedly connected to the upper chamber of the left auxiliary hydraulic cylinder (101) and the lower chamber of the right auxiliary hydraulic cylinder (101), respectively. The two liquid guide pipes (12) on the lower side of the main hydraulic cylinder (5) are fixedly connected to the lower chamber of the left auxiliary hydraulic cylinder (101) and the upper chamber of the right auxiliary hydraulic cylinder (101), respectively. Each of the four liquid guide pipes (12) is equipped with a liquid guide solenoid valve (13) and an electrically controlled throttle valve (14). The ankle joint support seat (4) is fixedly installed with a PLC controller, and the PLC controller is electrically connected to each liquid guide solenoid valve (13) and the electrically controlled throttle valve (14).

2. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, The spring telescopic rod (7) includes an inner sleeve (71), an outer sleeve (72) and a shock-absorbing spring (73). The outer sleeve (72) is slidably connected to the inner sleeve (71), and the outer sleeve (72) and the inner sleeve (71) are fixedly connected by the shock-absorbing spring (73). The inner sleeve (71) is fixedly installed on the inner bottom surface of the main hydraulic cylinder (5), and the upper end of the outer sleeve (72) is fixedly connected to the main piston (6).

3. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, The upper and lower chambers of the auxiliary hydraulic cylinder (101) are connected by a connecting pipe (15), and a follow-up solenoid valve (16) is provided on the connecting pipe (15). The follow-up solenoid valve (16) is electrically connected to the PLC controller.

4. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, Temperature sensors (17) are fixedly installed on the lower side of the left auxiliary hydraulic cylinder (101) and the upper side of the right auxiliary hydraulic cylinder (101), and the detection end of the temperature sensor (17) extends into the chamber of the corresponding auxiliary hydraulic cylinder (101). Both temperature sensors (17) are electrically connected to the PLC controller.

5. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, Several pressure sensors are fixedly arranged on the lower end face of the elastic foot plate (1), and an angle sensor that cooperates with the rotating shaft (3) is fixedly installed on the ankle joint connecting seat (2). Each of the pressure sensors and angle sensors is electrically connected to the PLC controller.

6. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, An elastic limiting strip (18) is fixedly provided between the elastic footplate (1) and the ankle joint support seat (4), and the elastic limiting strip (18) is used to provide flexible limiting for the ankle joint support seat (4) and the ankle joint connecting seat (2).

7. The dual-cylinder synergistic cooling hydraulic foot and ankle prosthesis according to claim 1, characterized in that, The main hydraulic cylinder (5) and the two auxiliary hydraulic cylinders (101) are each provided with a number of heat sinks (19), which are used to assist the main hydraulic cylinder (5) and the two auxiliary hydraulic cylinders (101) in heat dissipation.

Images