Self-locking joint and artificial limb
By designing a self-locking joint including cylinder block, rotating shaft, oil pressing part, swing arm and elastic parts, the problem of insufficient load-bearing self-locking function caused by the lack of independent hydraulic cylinders in the existing prosthetic knee joint is solved, and the true hydraulic load-bearing self-locking is achieved, which improves the stability and comfort of the prosthetic limb.
Patent Information
- Application Number
- CN202421560576.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-07-03
AI Technical Summary
Although the existing prosthetic knee joints have the function of self-locking load-bearing, due to the lack of independent hydraulic cylinders, it is impossible to achieve true hydraulic load-bearing self-locking, which can only be partially locked when taking into account the movement functions, which cannot meet the needs of stable support.
A self-locking joint is designed, including a cylinder block, a rotating shaft, an oil pressing member, a swing arm and an elastic member. Through the design of the oil cavity and oil passage, the oil pressing member and an oil needle are used to achieve the pressure and discharge of oil. The hem of the swing arm is controlled through the resistance of the elastic member, thereby blocking the oil passage, limiting the relative rotation of the rotating shaft and the cylinder, and realizing the load-bearing self-locking of the joint.
It realizes the true load-bearing self-locking of the prosthetic knee joint, which can simulate the knee joint movement when the user walks normally or runs, and stabilize support when flexing the knee or carrying weight, avoid excessive joint movement and improve user stability and comfort.
Smart Images
Figure CN222870724U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of medical instruments, in particular to a self-locking joint and a prosthesis. Background Art
[0002] As a substitute for the human knee joint, the prosthetic knee joint mainly has two control functions, namely safety control during the stance period and motion control during the swing period. Safety control during the stance period mainly includes manual lock control, load-bearing self-locking (mechanical and hydraulic) and electronic control. The manual lock control has a simple structure and low cost, but is inconvenient to use. The hydraulic load-bearing self-locking structure has very good reliability, but has certain difficulties in structural design and is not widely used at present. Electronic control has a high cost, is easily affected by the control program, and has average reliability.
[0003] Although some prosthetic knee joints on the market currently have load-bearing self-locking functions, they do not have independent hydraulic cylinders. Therefore, in order to take into account the movement function, they can only be partially locked (i.e., slowly flex the knee), and cannot achieve true hydraulic load-bearing self-locking. Utility Model Content
[0004] In view of this, the utility model provides a self-locking joint and prosthesis, which are used to solve the problem that some prosthetic knee joints in the prior art have a load-bearing self-locking function, but due to the lack of an independent hydraulic cylinder, in order to take into account the movement function, they can only be partially locked (i.e., slowly flex the knee), and cannot achieve true hydraulic load-bearing self-locking.
[0005] In order to achieve one or part or all of the above purposes or other purposes, the utility model proposes a self-locking joint, including a cylinder body, a rotating shaft, an oil pressure piece, a swing arm and an elastic piece, wherein the cylinder body is respectively provided with an oil chamber and an oil channel, and the upper end wall of the cylinder body is provided with a needle hole connected to the oil channel, the rotating shaft passes through the cylinder body and is rotatably connected to the cylinder body, the oil pressure piece is slidably connected in the oil chamber and is transmission-connected to the rotating shaft, the oil pressure piece divides the oil chamber into a front chamber and a rear chamber, one end of the oil channel is connected to the front chamber, and the other end of the oil channel is connected to the rear chamber, the front end of the swing arm is hinged to the upper end of the cylinder body, and the rear end of the swing arm is hinged with an oil needle, and the tip of the oil needle The elastic member is arranged on the oil cylinder and is used to prevent the swing arm from swinging down. The elastic resistance of the elastic member to the swing arm is D. When the load-bearing capacity of the swing arm is less than D, the swing arm and the cylinder body are relatively stationary. The swing arm can rotate relative to the cylinder body and the rotating shaft. The rotating shaft can drive the oil pressure member to slide in the oil chamber, and the oil in the front chamber is pressed into the rear chamber or the oil in the rear chamber is pressed into the front chamber through the oil channel. When the load-bearing capacity of the swing arm is greater than D, the swing arm will overcome the resistance of the elastic member and swing down, and drive the oil needle to slide down to block the oil channel. At this time, the oil will limit the sliding of the oil pressure member, thereby limiting the relative rotation of the rotating shaft and the cylinder body through the oil pressure member.
[0006] Preferably, the elastic member includes a spring, a slider and a connecting rod, a spring pressure chamber is provided at the lower end of the cylinder body, a guide opening is opened axially on the inner wall of the spring pressure chamber, the spring is arranged in the spring pressure chamber, the bottom end of the spring is connected to the bottom end of the spring pressure chamber, the slider is arranged at the top end of the spring and is slidably connected to the spring pressure chamber, the front end of the swing arm extends downward to form an elastic arm, one end of the connecting rod is hinged to the elastic arm, and the other end of the connecting rod is hinged to the slider through the guide opening.
[0007] Preferably, a lower through shaft is sleeved on the sliding block, and one end of the lower through shaft passes through the guide opening and is hinged to the other end of the connecting rod.
[0008] Preferably, the self-locking joint further comprises an adjusting knob, the bottom end of the spring cavity is through-connected, the adjusting knob is screwed into the bottom end of the spring cavity, and the bottom end of the spring abuts against the adjusting knob.
[0009] Preferably, the rotating shaft is rotatably connected to the cylinder body via a bearing.
[0010] Preferably, the end of the oil needle is sleeved with an upper through shaft, the rear end of the swing arm is provided with a waist-shaped hole, the end of the upper through shaft is sleeved in the waist-shaped hole, and can slide along the long axis direction of the waist-shaped hole.
[0011] Preferably, the oil chamber is coaxially arranged with the rotating shaft, and a partition portion is axially provided on one side wall of the oil chamber, and an arc-shaped concave surface is provided at the end of the partition portion away from the inner wall of the oil chamber, and the concave surface is coaxial with the rotating shaft and is slidably connected with the side wall of the rotating shaft. One side wall of the rotating shaft extends radially to form a plate-shaped oil-pressing part, and an arc-shaped convex surface is provided at the end of the oil-pressing part away from the rotating shaft, and the convex surface is coaxial with the oil chamber and is slidably connected with the inner wall of the oil chamber. The partition portion, the rotating shaft and the oil-pressing part divide the oil chamber into a front chamber and a rear chamber.
[0012] Preferably, the axis of the oil chamber is perpendicular to the axis of the rotating shaft, the oil pressure piece is a plunger, the plunger is slidably connected in the oil chamber, and divides the oil chamber into a front chamber and a rear chamber, the rotating shaft portion is located in the oil chamber, and a gear is coaxially provided on the portion of the rotating shaft located in the oil chamber, and a tooth groove is provided on the side wall of the plunger along the length direction, and the tooth groove is engaged with the gear.
[0013] Preferably, the self-locking joint further comprises a cylinder plug, one end of the oil chamber passes through, and the cylinder plug seals the through end of the oil chamber.
[0014] A prosthesis comprises the self-locking joint, a hollow frame and a damping cylinder, wherein the self-locking joint and the damping cylinder are sequentially arranged in the frame from top to bottom, the two ends of the rotating shaft are respectively fixedly connected to the inner walls corresponding to the frame, the damping cylinder is hinged on the inner wall of the frame, and the telescopic rod of the damping cylinder is hinged to the lower end of the cylinder body.
[0015] Implementing the embodiments of the present utility model will have the following beneficial effects:
[0016] After adopting the above-mentioned self-locking joint and prosthesis, the self-locking joint can be installed at the lower end of the user's thigh in conjunction with the corresponding prosthesis. D can be equal to the force applied to the swing arm when the user walks or runs upright. Therefore, when the user walks or runs normally, the elastic member can prevent the swing arm from swinging down relative to the cylinder body to prevent the oil needle from blocking the oil channel. The swing arm can rotate relative to the cylinder body and the rotating shaft. The rotating shaft can drive the oil pressure piece to slide adaptively in the oil chamber, and the oil in the front chamber is pressed into the rear chamber or the oil in the rear chamber is pressed into the front chamber through the oil channel, thereby simulating the movement of the knee joint. When the user bends his knees or bears weight, the force acting on the swing arm will exceed D due to the increase in the force arm or weight. At this time, the swing arm will overcome the resistance of the elastic member and swing down, and drive the oil needle to slide down to block the oil channel. The oil will limit the sliding of the oil pressure piece, thereby limiting the relative rotation of the rotating shaft and the cylinder body through the oil pressure piece, realizing the true load-bearing self-locking of the joint and achieving the purpose of limiting the movement of the joint so that the joint can stably support the user. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0018] in:
[0019] Figure 1 It is a three-dimensional diagram of the utility model;
[0020] Figure 2 It is an exploded view of the second embodiment of the utility model;
[0021] Figure 3 It is a side sectional view of the first embodiment of the utility model;
[0022] Figure 4 for Figure 3 A partial view of
[0023] Figure 5 It is a partial view of the side section view of the second embodiment of the utility model.
[0024] In the figure: 1. cylinder body; 11. oil channel; 12. needle hole; 13. spring pressure chamber; 14. guide port; 15. partition; 151. concave surface; 16. cylinder plug; 2. rotating shaft; 21. gear; 3. oil pressure piece; 31. convex surface; 32. tooth groove; 4. swing arm; 41. elastic arm; 42. waist-shaped hole; 5. elastic piece; 51. spring; 52. slider; 53. connecting rod; 54. lower through shaft; 55. adjusting knob; 6. oil needle; 61. upper through shaft; 8. frame; 9. damping cylinder; 91. telescopic rod; a. oil chamber; b. front chamber; c. rear chamber. DETAILED DESCRIPTION
[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.
[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0027] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings.
[0028] like Figure 1-5 As shown, a self-locking joint comprises a cylinder body 1, a rotating shaft 2, an oil pressure piece 3, a swing arm 4 and an elastic piece 5. An oil chamber a and an oil passage 11 are respectively provided in the cylinder body 1. A needle hole 12 connected to the oil passage 11 is opened on the upper end wall of the cylinder body 1. The rotating shaft 2 passes through the cylinder body 1 and is rotatably connected to the cylinder body 1. The oil pressure piece 3 is slidably connected in the oil chamber a and is transmission-connected to the rotating shaft 2. The oil pressure piece 3 divides the oil chamber a into a front chamber b and a rear chamber c. One end of the oil passage 11 is connected to the front chamber b, and the other end of the oil passage 11 is connected to the rear chamber c. The front end of the swing arm 4 is hinged to the upper end of the cylinder body 1, and the rear end of the swing arm 4 is hinged with an oil needle 6, and the tip of the oil needle 6 is slidably connected in the needle hole 12. The elastic piece 5 is arranged on the oil cylinder. The elastic piece 5 is used to prevent the swing arm 4 from swinging down, and the elastic resistance of the elastic piece 5 to the swing arm 4 is D.
[0029] In this embodiment, the self-locking joint can be installed at the lower end of the user's thigh in conjunction with a corresponding prosthesis. D can be equal to the force applied to the swing arm 4 when the user walks or runs upright. Therefore, when the user walks or runs normally, the elastic member 5 can prevent the swing arm 4 from swinging downward relative to the cylinder body 1, preventing the oil needle 6 from blocking the oil passage 11. The swing arm 4 can rotate relative to the cylinder body 1 and the rotating shaft 2. The rotating shaft 2 can drive the oil pressure member 3 to slide adaptively in the oil chamber a, and the oil in the front chamber b is pressed into the rear chamber c or the oil in the front chamber c is pressed into the rear chamber c through the oil passage 11. The oil in the rear chamber c is pressed into the front chamber b, thereby simulating the movement of the knee joint. When the user bends his knees or bears weight, the force acting on the swing arm 4 will exceed D due to the increase in the lever arm or weight. At this time, the swing arm 4 will overcome the resistance of the elastic part 5 and swing down, and drive the oil needle 6 to slide down to block the oil channel 11. The oil will limit the sliding of the oil pressure part 3, thereby limiting the relative rotation of the rotating shaft 2 and the cylinder body 1 through the oil pressure part 3, realizing the true load-bearing self-locking of the joint, and achieving the purpose of limiting the movement of the joint so that the joint can stably support the user.
[0030] Furthermore, the elastic member 5 includes a spring 51, a slider 52 and a connecting rod 53. A spring-pressing chamber 13 is provided at the lower end of the cylinder body 1. A guide opening 14 is opened axially on the inner wall of the spring-pressing chamber 13. The spring 51 is arranged in the spring-pressing chamber 13. The bottom end of the spring 51 is connected to the bottom end of the spring-pressing chamber 13. The slider 52 is arranged at the top end of the spring 51 and is slidably connected to the spring-pressing chamber 13. The front end of the swing arm 4 extends downward to form an elastic arm 41. One end of the connecting rod 53 is hinged to the elastic arm 41, and the other end of the connecting rod 53 is hinged to the slider 52 through the guide opening 14.
[0031] Specifically, when the swing arm 4 is under pressure, the swing arm 4 has a tendency to swing downward, and the elastic arm 41 will pull the slider 52 through the connecting rod 53, applying a force to the slider 52 to slide toward the bottom of the spring-pressing chamber 13. At this time, the slider 52 will squeeze the spring 51. When the force applied to the swing arm 4 is less than or equal to D, the elastic force of the spring 51 will support the swing arm 4 to prevent the swing arm 4 from swinging downward relative to the cylinder body 1. When the force applied to the swing arm 4 is greater than D, the swing arm 4 will swing downward relative to the cylinder body 1, and the elastic arm 41 will drive the slider 52 to slide toward the bottom of the spring-pressing chamber 13 through the connecting rod 53, and use the slider 52 to compress the spring 51.
[0032] Furthermore, a lower through shaft 54 is sleeved on the slider 52, and one end of the lower through shaft 54 passes through the guide opening 14 and is hinged to the other end of the connecting rod 53. In the present embodiment, two guide openings 14, two elastic arms 41 and two connecting rods 53 are each provided, and the two guide openings 14 are symmetrically arranged on the inner walls on both sides of the elastic pressure cavity 13. The two ends of the lower through shaft 54 respectively pass through the corresponding guide openings 14 to the outside, and the elastic arms 41 and the connecting rod 53 are arranged one by one corresponding to the ends of the lower through shaft 54.
[0033] Furthermore, the self-locking joint also includes an adjusting knob 55, the bottom end of the spring cavity 13 is through-connected, the adjusting knob 55 is screwed into the bottom end of the spring cavity 13, and the bottom end of the spring 51 abuts against the adjusting knob 55. The user can rotate the adjusting knob 55 so that the tip of the adjusting knob 55 squeezes the spring 51 or relaxes the squeezing of the spring 51, thereby adjusting the elastic force of the spring 51 on the slider 52 and changing the elastic resistance of the spring 51 to the swing arm 4, so that the self-locking joint can adapt to users of different weights.
[0034] Furthermore, the rotating shaft 2 is rotatably connected to the cylinder body 1 via a bearing to improve the smoothness of the relative rotation between the cylinder body 1 and the rotating shaft 2, thereby improving the flexibility of the joint.
[0035] Furthermore, an upper through shaft 61 is sleeved on the end of the oil needle 6, and a waist-shaped hole 42 is provided at the rear end of the swing arm 4. The end of the upper through shaft 61 is inserted into the waist-shaped hole 42. When the swing arm 4 swings relative to the cylinder body 1, the upper through shaft 61 can slide adaptively along the long axis direction of the waist-shaped hole 42 to avoid interference between the swing arm 4 and the oil needle 6, thereby ensuring that the oil needle 6 slides normally in the needle hole 12.
[0036] Embodiment 1:
[0037] like Figure 3-4 As shown, further, the oil chamber a is coaxially arranged with the rotating shaft 2, and a partition 15 is axially arranged on one side wall of the oil chamber a, and an arc-shaped concave surface 151 is arranged at one end of the partition 15 away from the inner wall of the oil chamber a, and the concave surface 151 is coaxial with the rotating shaft 2 and is slidably connected with the side wall of the rotating shaft 2. A side wall of the rotating shaft 2 extends radially to form a plate-shaped oil pressure piece 3, and an arc-shaped convex surface 31 is arranged at one end of the oil pressure piece 3 away from the rotating shaft 2, and the convex surface 31 is coaxial with the oil chamber a and is slidably connected with the inner wall of the oil chamber a. The partition 15, the rotating shaft 2 and the oil pressure piece 3 divide the oil chamber a into a front chamber b and a rear chamber b. Chamber c. Under normal circumstances, the front chamber b and the rear chamber c are interconnected through the oil passage 11. The oil pressure piece 3 can rotate relative to the rotating shaft 2 and the cylinder body 1, and the oil in the front chamber b is pressed into the rear chamber c or the oil in the rear chamber c is pressed into the front chamber b. When the swing arm 4 overcomes the resistance of the spring 51 and swings down relative to the cylinder body 1, the oil needle 6 will slide down along the needle hole 12 synchronously and block the oil passage 11. At this time, the oil in the front chamber b and the rear chamber c are not connected to each other, and the oil will limit the rotation and sliding of the oil pressure piece 3 in the oil chamber a, thereby limiting the relative rotation of the rotating shaft 2 and the cylinder body 1 through the oil pressure piece 3, and realizing the load-bearing self-locking of the joint.
[0038] Embodiment 2:
[0039] like Figure 2 and Figure 5As shown, further, the axis of the oil chamber a is perpendicular to the axis of the rotating shaft 2, the oil pressure member 3 is a plunger, the plunger is slidably connected in the oil chamber a, and the oil chamber a is divided into a front chamber b and a rear chamber c, the rotating shaft 2 is partially located in the oil chamber a, and a gear 21 is coaxially provided on the portion of the rotating shaft 2 located in the oil chamber a, and a tooth groove 32 is provided on the side wall of the plunger along the length direction, and the tooth groove 32 is meshed with the gear 21. Under normal conditions, the front chamber b and the rear chamber c are interconnected through the oil passage 11, and the cylinder body 1 can rotate relative to the rotating shaft 2, thereby 1 drives the plunger to slide along the oil chamber a, and presses the oil in the front chamber b into the rear chamber c or presses the oil in the rear chamber c into the front chamber b. When the swing arm 4 overcomes the resistance of the spring 51 and swings down relative to the cylinder body 1, the oil needle 6 will slide down along the needle hole 12 synchronously and block the oil channel 11. At this time, the oil in the front chamber b and the rear chamber c are not connected to each other, and the oil will prevent the plunger from sliding in the oil chamber a. Since the tooth groove 32 of the plunger is engaged with the gear 21 of the rotating shaft 2, the plunger will limit the relative rotation of the rotating shaft 2 and the cylinder body 1, thereby realizing the load-bearing self-locking of the joint.
[0040] Furthermore, the self-locking joint also includes a cylinder plug 16, one end of the oil chamber a is passed through, and the cylinder plug 16 seals the through end of the oil chamber a so that the plunger can be installed into the oil chamber a through the opening of the oil chamber a. The cylinder plug 16 can seal the oil chamber a by means of threaded connection.
[0041] A prosthesis includes a self-locking joint and a hollow frame 8 and a damping cylinder 9. The self-locking joint and the damping cylinder 9 are arranged in the frame 8 from top to bottom. The two ends of the rotating shaft 2 are respectively fixedly connected to the inner walls corresponding to the frame 8. The damping cylinder 9 is hinged on the inner wall of the frame 8. The telescopic rod 91 of the damping cylinder 9 is hinged to the lower end of the cylinder body 1. In this embodiment, the damping cylinder 9 is a hydraulic cylinder. When the user walks or runs normally, the cylinder body 1 will rotate relative to the rotating shaft 2. At this time, the cylinder body 1 will drive the telescopic rod 91 of the damping cylinder 9 to retract or extend. The user can adjust the throttle valve opening of the damping cylinder 9, thereby changing the flexion and extension damping of the telescopic rod 91, so as to achieve the purpose of adjusting the user's walking speed and gait.
[0042] In one embodiment, the damping cylinder 9 is a pneumatic cylinder.
[0043] Obviously, the embodiments described above are only some embodiments of the utility model, rather than all embodiments. The preferred embodiments of the utility model are given in the accompanying drawings, but they do not limit the patent scope of the utility model. The utility model can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the utility model more thorough and comprehensive. Although the utility model is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to replace some of the technical features therein with equivalents. Any equivalent structure made using the contents of the utility model specification and the accompanying drawings, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the utility model.
Claims
1. A self-locking joint, characterized in that: include: Cylinder body, rotating shaft, oil pressing parts, swing arms and elastic parts; The cylinder body is provided with an oil chamber and an oil passage, respectively; a pinhole connected to the oil passage is provided on the upper end wall of the cylinder body; the rotating shaft penetrates the cylinder body and is rotatably connected to the cylinder body; the oil pressure piece is slidably connected in the oil chamber and is transmission-connected to the rotating shaft; the oil pressure piece divides the oil chamber into a front chamber and a rear chamber; one end of the oil passage is connected to the front chamber, and the other end of the oil passage is connected to the rear chamber; The front end of the swing arm is hinged to the upper end of the cylinder body, and the rear end of the swing arm is hinged with an oil needle, and the tip of the oil needle is slidably connected in the needle hole; The elastic member is arranged on the oil cylinder, and is used to prevent the swing arm from swinging downward, and the elastic resistance of the elastic member to the swing arm is D; When the load-bearing capacity of the swing arm is less than D, the swing arm and the cylinder body are relatively stationary, and the swing arm can rotate relatively with the cylinder body and the rotating shaft, and the rotating shaft can drive the oil pressure piece to slide in the oil chamber, and press the oil in the front chamber into the rear chamber or press the oil in the rear chamber into the front chamber through the oil channel; When the load-bearing capacity of the swing arm is greater than D, the swing arm will overcome the resistance of the elastic part and swing down, and drive the oil needle to slide down to block the oil channel. At this time, the oil will limit the sliding of the oil pressure part, thereby limiting the relative rotation of the rotating shaft and the cylinder body through the oil pressure part.
2. A self-locking joint according to claim 1, characterized in that: The elastic member includes a spring, a slider and a connecting rod; A spring-pressing chamber is provided at the lower end of the cylinder body, and a guide opening is opened axially on the inner wall of the spring-pressing chamber. The spring is arranged in the spring-pressing chamber, and the bottom end of the spring is connected to the bottom end of the spring-pressing chamber. The slider is arranged at the top end of the spring and is slidably connected to the spring-pressing chamber. The front end of the swing arm extends downward to form an elastic arm, one end of the connecting rod is hinged to the elastic arm, and the other end of the connecting rod is hinged to the slider through the guide opening.
3. A self-locking joint according to claim 2, characterized in that: A lower through shaft is sleeved on the sliding block, and one end of the lower through shaft passes through the guide opening and is hinged to the other end of the connecting rod.
4. A self-locking joint according to claim 2, characterized in that: The self-locking joint also includes an adjusting knob, the bottom end of the spring cavity is through, the adjusting knob is screwed into the bottom end of the spring cavity, and the bottom end of the spring abuts against the adjusting knob.
5. A self-locking joint according to claim 1, characterized in that: The rotating shaft is rotatably connected to the cylinder body through a bearing.
6. A self-locking joint according to claim 1, characterized in that: The end of the oil needle is sleeved with an upper through shaft, the rear end of the swing arm is provided with a waist-shaped hole, the end of the upper through shaft is sleeved in the waist-shaped hole and can slide along the long axis direction of the waist-shaped hole.
7. A self-locking joint according to claim 1, characterized in that: The oil chamber is coaxially arranged with the rotating shaft, and a partition portion is axially arranged on one side wall of the oil chamber, and an arc-shaped concave surface is arranged at one end of the partition portion away from the inner wall of the oil chamber, and the concave surface is coaxial with the rotating shaft and is slidably connected with the side wall of the rotating shaft. One side wall of the rotating shaft extends radially to form a plate-shaped oil-pressing part, and an arc-shaped convex surface is arranged at one end of the oil-pressing part away from the rotating shaft, and the convex surface is coaxial with the oil chamber and is slidably connected with the inner wall of the oil chamber. The partition portion, the rotating shaft and the oil-pressing part divide the oil chamber into a front chamber and a rear chamber.
8. A self-locking joint according to claim 1, characterized in that: The axis of the oil chamber is perpendicular to the axis of the rotating shaft. The oil pressure piece is a plunger, which is slidably connected in the oil chamber and divides the oil chamber into a front chamber and a rear chamber. The rotating shaft is partially located in the oil chamber, and a gear is coaxially provided on the part of the rotating shaft located in the oil chamber. A tooth groove is provided on the side wall of the plunger along the length direction, and the tooth groove is meshed with the gear.
9. A self-locking joint according to claim 8, characterized in that: The self-locking joint also includes a cylinder plug, one end of the oil chamber is passed through, and the cylinder plug seals the through end of the oil chamber.
10. A prosthesis, characterized in that: It comprises the self-locking joint as described in any one of claims 1 to 9, and a hollow frame and a damping cylinder, wherein the self-locking joint and the damping cylinder are sequentially arranged in the frame from top to bottom, the two ends of the rotating shaft are respectively fixedly connected to the inner walls corresponding to the frame, the damping cylinder is hinged on the inner wall of the frame, and the telescopic rod of the damping cylinder is hinged to the lower end of the cylinder body.