Design of pneumatic knee joint for disabled people

1 The overall structure of the pneumatic knee joint The pneumatic knee joint consists of a linkage mechanism and a damper cylinder. 1. According to the requirement that the rotation range of the human knee joint is less than 180, the linkage mechanism can adopt a double rocker structure to ensure the weight of the simulated human body when standing. The stability should be limited by the direction of rotation of the rocker. It can only start from the limit point, turn clockwise and counterclockwise to limit the point. The limit point is just where the person is in a standing position. The linkage mechanism is low in the low-profile soul, which can meet the requirements of long-term use. The linkage mechanism is simple, small and light, and is suitable for the weight of the prosthesis fr0O.6lIPiUlnHS6O8OM. The damper can be designed on the cylinder block, or it can be designed in the structure of the live thigh connection resistor. There are two types of structure: the non-closing speed rehabilitation industry, the damper bears less impact quality, and is convenient for structural and design calculations. There is no damper to close the speed. Load displacement curve without closing speed damper 2. The ordinate is the impact load. The abscissa is a parabolic relationship of displacement speed 1 and 1 . The main parameters of the damper are the maximum impact load of the damper, the damper, the pressure corpse damper, the closing force, the response frequency of the damper, and the damper response time.

The squatting impact load factory can be loaded according to the standard. 52 times consider the damper opening pressure, (4) the responsive damper closes the response frequency of the dynamic cardi damper = 31 damper response, the 50 damper uses a manually adjustable variable orifice, according to the fluid continuity equation, Through the flow rate of the orifice, from the continuous square, the mass flow formula of the fluid passing through the orifice is obtained, wherein the effective area of ​​the orifice is! 2; the absolute force of the gas upstream of the orifice is the absolute pressure of the gas downstream of the orifice, the flow is represented by a coefficient of seven orifices, the density of the upstream body is seven, and the gas density downstream of the orifice is the absolute temperature of the gas upstream of the orifice; The absolute temperature of the gas downstream of the orifice is seen as a function of the flow rate and flow rate for the change within 1 . In two cases, 1弋0 less 7 0.528, the flow rate flow does not change with the change of households, the flow rate Zibo Shandong Institute of Engineering, 255012 2 South Shandong Province prosthetic orthopedic rehabilitation center flows, for the speed of sound, 2+.528.1., the airflow is The subsonic flow, the flow rate and the flow rate are all measured according to the formulas 1 and 2, respectively, and the column is increased to decrease.

This result shows that at the beginning of flexion and extension, the velocity of buckling and stretching is basically constant due to the fire of 0.528. As the movement progresses, the speed of buckling and stretching gradually slows down, which plays a good buffering role. .

3 force balance equation, cylinder pressure cylinder cylinder area; pressure chamber pressure; factory piston displacement, spring pre-adjustment spring stiffness coefficient buckling resistance or extension resistance; heart conversion coefficient, shape shift by the linkage mechanism, large, human body buckling As the angle increases, the force arm becomes longer. To ensure the balance of the human body, the buckling resistance needs to be gradually increased. When the number is taken, it is the stretching force. When the bending force is changed to the stretching force, the stretching resistance is the largest, and then gradually decreases. Both the buckling resistance and the extension resistance can be adjusted by changing the pre-adjustment of the magazine.

4 Conclusion In addition to the basic actions required by the exhibition, it also has the advantage of adjustable adjustable speed and adjustable speed. It is a mature and practical design and the first choice for replacing imported products.

5 References 1 Li Jianwei. Air pressure conveys system dynamics. South China University of Technology Press, 1991.

2 Wang Shugong. Hydraulic dampers study hydraulics and pneumatics and seals. 1998.1.

Research and clinical application of titanium alloy aluminum oxide coating combined with adjustable inner limb prosthesis Sun Yuan Su Jin 1 1 profile nearly 50, a large number of domestic and foreign reports of 1 knife defibrillation, customized artificial hip and knee prosthesis replacement The new technology replaces the old methods of inactivation and replantation of previous amputation, and opens up new ways for patients to retain residual limbs.

In the United States in 1940, the elbow was replaced by a custom-made tumor 甩+rust steel total hip section in the proximal part of the femur. In 1983, the US company and the hospital jointly developed a tumor-type titanium-based gold-cast knee-knee joint. The 茗Titanium Gongshu book details the application of nearly 100 cases since the 1970s.

The design of the lower extremity prosthesis of a patient aged 816 years, 1983, reported that 60 children were stretched and painted joints in 1993. During the follow-up of 40 patients, many patients were found to have loosening and medullary needle displacement, and need to be repaired. The adjustable length was 214. The Royal Hospital of Birmingham in the United Kingdom reported 75 stretchable prostheses and 52 prostheses since 1976. Broken, the infection rate was 20.23. Introduced both the retractable and modular endoprostheses with a range of 3.6. For example, titanium spots were found to precipitate black around the joint capsule and prosthesis. Three patients were broken at the thread, with a 5-year repair rate of 45 and a modular version of 25. The US tended to use the combination. In 1999, the Royal Orthopaedic Hospital reported the use of intra-femoral prostheses in 165 patients with malignant bone tumors in 20 years. For 54 follow-ups, 57 were not repaired in 20 years, the infection rate was 1.8, and the average function was 25 points, preferably 30 points. The reason for success is the use of cemented hip joints.

American River, Clinical and Basic Department of Orthopaedic Division 1970 1992081 Tumor joints 2,56 successful 35 1 Beijing Institute of Aeronautical Materials Beijing Aviation Materials Baimu Import and Export Corporation Jinghang Biomedical Engineering Company, Beijing Jianguomenwai Donghuan South Road No. 2 Amy Building Floor, 100022