A hydraulic energy storage ankle joint

Abstract

The present invention discloses a hydraulic energy storage ankle joint, comprising an outer housing, a footplate, a hydraulic mechanism, a two-position, three-way reversing valve, a diaphragm accumulator, and a normal-pressure oil tank. The hydraulic mechanism comprises two cam-piston-cylinder mechanisms, each consisting of a cam fixed to the footplate, a hydraulic cylinder with a top fixed to the outer housing, and a piston pushrod. The accumulator and oil tank are mounted within the outer housing. Reversing valves are installed on both hydraulic cylinders, connecting them to the accumulator and oil tank, respectively, during different operating phases to exchange oil. The hydraulic energy storage ankle joint provided by the present invention stores and releases energy through a hydraulic system, providing assistance to the wearer while walking.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluid machinery, and in particular relates to a hydraulic energy storage ankle joint. Background Art

[0002] Because current medical technology is unable to repair and reconnect residual limbs, prosthetic limbs remain the most common and optimal treatment. For people with disabilities, prosthetic limbs not only allow them to return to normal life after an accident but also enhance their confidence and courage in facing life. Therefore, prosthetic limbs play a vital role not only in medical treatment but also in social development.

[0003] When the human body walks, the movement of the ankle joint can be regarded as a compound movement in three-dimensional space. During the walking process, the ankle joint performs dorsiflexion and plantar flexion, inversion and eversion, adduction and abduction. Therefore, the ankle joint plays an important role in the patient's lower limb motor rehabilitation.

[0004] Currently, on the market, ankle joints are divided into active and passive types based on different driving methods. Among them, passive prostheses mainly rely on elastic or damping elements to store and release energy. These elements store energy during the dorsiflexion phase and then release it during the plantar flexion phase to assist walking; active prostheses use active components, which can provide assistance to the wearer during walking, reduce the burden on the legs, and thus reduce energy consumption. Although active prostheses have strong flexibility during work, the R&D, manufacturing and maintenance costs are too high, and the stability is poor, which needs to be further improved. Passive prostheses have a simple structure, low cost, and broader market prospects, but they cannot provide torque assistance to patients and have poor flexibility. Therefore, the vast majority of prostheses on the market have limitations.

[0005] Current designs for powered ankle joints utilize common drive methods, including motors, pneumatics, and hydraulics. Hydraulic drive, which uses hydraulic oil as a medium, offers low control difficulty for speed and displacement, high precision, and a simple structure. Therefore, this project chose hydraulic drive to design the ankle joint. Summary of the Invention

[0006] The purpose of the present invention is to solve the above problems and provide a hydraulic energy storage ankle joint, which is characterized by: including an outer cover, an upper foot plate, a lower foot plate, a cam hydraulic system, an oil pipeline, a diaphragm accumulator, a normal pressure oil tank, a reversing valve I and a reversing valve II, and the cam hydraulic system, the diaphragm accumulator and the normal pressure oil tank are all located inside the outer cover.

[0007] Preferably, the cam hydraulic system includes a cylinder body, a piston push rod, and a cam, the cylinder body includes a first cylinder body and a second cylinder body, the first cylinder body and the second cylinder body are fixedly connected to the top of the outer cover side by side; the piston push rod includes a first piston push rod and a second piston push rod, the cam includes a first cam and a second cam, the piston at the top of the first piston push rod is located in the first cylinder body, and the bottom end is the pointed push rod of the first cam, the piston at the top of the second piston push rod is located in the second cylinder body, and the bottom end is the pointed push rod of the second cam.

[0008] Preferably, the reversing valve I and the reversing valve II are respectively installed on the outer walls of the first cylinder body and the second cylinder body, wherein the reversing valve I is directly connected to the upper hole of the first cylinder body and the lower hole of the first cylinder body, and the reversing valve II is directly connected to the upper hole of the second cylinder body and the lower hole of the second cylinder body; the reversing valve I and the reversing valve II are respectively connected to the diaphragm accumulator and the atmospheric pressure oil tank through oil pipelines; the oil pipeline is divided into a first pipeline, a second pipeline, a third pipeline and a fourth pipeline; the first pipeline is respectively connected to the reversing valve I and the oil chamber of the diaphragm accumulator, the second pipeline is respectively connected to the reversing valve I and the atmospheric pressure oil tank, the third pipeline is respectively connected to the reversing valve II and the oil chamber of the diaphragm accumulator, and the fourth pipeline is respectively connected to the reversing valve II and the atmospheric pressure oil.

[0009] Preferably, the first cam is parallel to the second cam, and the bottom is fixedly mounted on the upper footboard; the axial hole of the first cam, the axial hole of the second cam 4 and the axial hole at the bottom end of the outer cover are aligned.

[0010] The beneficial effect of the present invention is that the hydraulic energy storage ankle joint provided by the present invention can store the energy generated by the wearer's ankle dorsiflexion stage and release this energy during the ankle plantar flexion stage, providing walking assistance for the wearer. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the external structure of a hydraulic energy storage ankle joint of the present invention;

[0012] Figure 2 This is a schematic diagram of the internal structure of a hydraulic energy storage ankle joint of the present invention;

[0013] Figure 3 It is a schematic diagram of the hydraulic system of the present invention.

[0014] Explanation of the accompanying symbols: 1. Outer cover; 2. Upper foot plate; 3. Lower foot plate; 4. Second cam; 5. First cam; 6. Second piston push rod; 7. Second cylinder body; 8. First cylinder body; 9. First piston push rod; 10. Reversing valve I; 11. Reversing valve II; 12. Diaphragm accumulator; 13. Normal pressure oil tank; 14. First pipeline; 15. Second pipeline; 16. Third pipeline; 17. Fourth pipeline; 21. Outer cover shaft hole; 41. Second camshaft hole; 51. First camshaft hole; 61. Bottom tip of second piston push rod; 62. Top piston of second piston push rod; 71. Upper hole of second cylinder body; 72. Lower hole of second cylinder body; 81. Upper hole of first cylinder body; 82. Lower hole of first cylinder body; 91. Bottom tip of first piston push rod; 92. Top piston of first piston push rod; 121. Air chamber of diaphragm accumulator; 122. Oil chamber of diaphragm accumulator. DETAILED DESCRIPTION

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0016] like Figures 1 to 3 As shown, the present invention provides a hydraulic energy storage ankle joint, including an outer cover, a foot plate, a cam hydraulic system, an oil pipeline, a diaphragm accumulator, a normal pressure oil tank, a reversing valve I and a reversing valve II, wherein the cam hydraulic system, the diaphragm accumulator and the normal pressure oil tank are all located inside the outer cover.

[0017] The cam hydraulic system includes a cylinder body, a piston push rod, and a cam. The cylinder body includes a first cylinder body and a second cylinder body. The first cylinder body and the second cylinder body are fixedly connected to the top of the outer cover side by side; the piston push rod includes a first piston push rod and a second piston push rod. The cam includes a first cam and a second cam. The piston at the top of the first piston push rod is located in the first cylinder body, and the bottom end is the pointed push rod of the first cam. The piston at the top of the second piston push rod is located in the second cylinder body, and the bottom end is the pointed push rod of the second cam.

[0018] The reversing valve I and reversing valve II are respectively installed on the outer walls of the first cylinder body and the second cylinder body, wherein the reversing valve I is directly connected to the upper hole of the first cylinder body and the lower hole of the first cylinder body, and the reversing valve II is directly connected to the upper hole of the second cylinder body and the lower hole of the second cylinder body; the reversing valve I and reversing valve II are respectively connected to the diaphragm accumulator and the atmospheric pressure oil tank through oil pipelines; the oil pipeline is divided into a first pipeline, a second pipeline, a third pipeline and a fourth pipeline; the first pipeline is respectively connected to the reversing valve I and the oil chamber of the diaphragm accumulator, the second pipeline is respectively connected to the reversing valve I and the atmospheric pressure oil tank, the third pipeline is respectively connected to the reversing valve II and the oil chamber of the diaphragm accumulator, and the fourth pipeline is respectively connected to the reversing valve II and the atmospheric pressure oil.

[0019] In this embodiment, the system operates in two phases based on the functions to be implemented. In the first phase, the wearer's walking enters passive dorsiflexion, and the system stores energy. At this point, the first cylinder is connected to the oil chamber of the pre-charged diaphragm accumulator via a first pipe, while the second cylinder is connected to the atmospheric pressure tank via a fourth pipe. As the footplate rotates toward the outer cover, the first piston, pushed by the first cam, rises along the inner wall of the first cylinder, pushing the oil in the first cylinder along the first pipe into the oil chamber of the diaphragm accumulator, compressing the pre-charged gas in the air chamber. Simultaneously, the oil in the second cylinder enters the atmospheric pressure tank along the fourth pipe, thus reducing the pressure in the second cylinder to negligible levels.

[0020] In the second phase, the wearer's walking progresses into passive dorsiflexion, and the system begins to store energy. At this point, the second cylinder is connected to the pre-charged diaphragm accumulator's oil chamber via a third pipe, while the first cylinder is connected to the atmospheric pressure tank via a second pipe. During this process, the compressed gas in the diaphragm accumulator pushes the oil in the oil chamber along the third pipe into the second cylinder, driving the second piston downward along the second cylinder, which in turn rotates the second cam, completing the process of moving the foot away from the outer cover. Simultaneously, the oil in the atmospheric pressure tank enters the first cylinder along the second pipe, thus reducing the pressure within the first cylinder to negligible levels.

[0021] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific descriptions and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical teachings disclosed in the present invention without departing from the essence of the present invention, and such variations and combinations are still within the scope of protection of the present invention.

Claims

1. A hydraulic energy storage ankle joint, characterized by: The invention comprises an outer cover (1), an upper foot plate (2), a lower foot plate (3), a cam hydraulic system, an oil pipeline, a diaphragm accumulator (12), a normal pressure oil tank (13), a reversing valve I (10) and a reversing valve II (11), wherein the cam hydraulic system, the diaphragm accumulator (12) and the normal pressure oil tank (13) are all located inside the outer cover (1); the cam hydraulic system comprises a cylinder body, a piston push rod and a cam, wherein the cylinder body comprises a first cylinder body (8), a second cylinder body (7), the first cylinder body (8) and the second cylinder body (7) are connected to each other. The cylinder body (7) is fixedly connected to the top of the outer cover (1) side by side; the piston push rod includes a first piston push rod (9) and a second piston push rod (6); the cam includes a first cam (5) and a second cam (4); the piston (92) is located in the first cylinder body (8), and the bottom end is the bottom peak (91) of the first piston push rod; the top piston (62) of the first piston push rod is located in the second cylinder body (7), and the bottom end is the bottom peak (61) of the second piston push rod; the reversing valve I (10) and the reversing valve II (1 1) are respectively installed on the outer wall of the first cylinder body (8) and the second cylinder body (7), wherein the reversing valve I (10) is directly connected to the upper hole (81) of the first cylinder body and the lower hole (82) of the first cylinder body, and the reversing valve II (11) is directly connected to the upper hole (71) of the second cylinder body and the lower hole (72) of the second cylinder body; the reversing valve I (10) and the reversing valve II (11) are respectively connected to the diaphragm accumulator (12) and the atmospheric pressure oil tank (13) through the oil pipeline; the oil pipeline is divided into a first pipeline (14) , a second pipeline (15), a third pipeline (16) and a fourth pipeline (17); the first pipeline (14) is connected to the reversing valve I (10) and the diaphragm accumulator oil chamber (122) respectively, the second pipeline (15) is connected to the reversing valve I (10) and the normal pressure oil tank (13) respectively, the third pipeline (16) is connected to the reversing valve II (11) and the diaphragm accumulator oil chamber (122) respectively, and the fourth pipeline (17) is connected to the reversing valve II (11) and the normal pressure oil tank (13) respectively.

2. A hydraulic energy storage ankle joint according to claim 1, characterized in that: The first cam (5) is parallel to the second cam (4), and the bottom is fixedly mounted on the upper footboard (2); the first cam shaft hole (51), the second cam shaft hole (41) and the outer cover shaft hole (21) are aligned.

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