Fan blade-type flow regulation damping cylinder used for intelligent knee joint

Abstract

The invention relates to the field of wheelchairs, and discloses a fan blade-type flow regulation damping cylinder used for an intelligent knee joint. The fan blade-type flow regulation damping cylinder is used for controlling flowing of hydraulic oil, and thereby, the damping degree of the knee joint is regulated, and the fan blade-type flow regulation damping cylinder is characterized by comprising a cylinder block, a damping regulation seat, a first one-way valve, a second one-way valve, a reversing valve and a DC servo motor, wherein the cylinder block is provided with a first chamber anda second chamber separated from each other by a push rod; the damping regulation seat is arranged on the cylinder block, and is provided with a stretching hydraulic channel and a flexion hydraulic channel communicating with the first chamber and the second chamber respectively; the first one-way valve is used for preventing backflow of hydraulic oil in the second chamber; the second one-way valveis used for preventing backflow of hydraulic oil in the first chamber; the reversing valve is rotationally connected with the damping regulation seat and is located between the stretching hydraulic channel and the flexion hydraulic channel; and the DC servo motor is installed on the damping regulation seat, and is used for driving the reversing valve to rotate. The DC servo motor drives the reversing valve to rotate to control flow cross sections of the stretching hydraulic channel and the flexion hydraulic channel, thereby regulating the damping degree of the damping cylinder.

Description

Technical field [0001] The embodiment of the present invention relates to the field of wheelchairs, and in particular to a fan-type flow adjustment damping cylinder for smart knee joints. Background technique [0002] Smart knee joint refers to the control of the knee joint damper through a microcomputer to control the speed of the swing phase and the stability of the support phase at the same time, making the lower limb patients walk closer to the gait of a healthy person when wearing a prosthetic limb, with higher followability and symmetry . At present, there are three main ways to adjust damping in smart knee joints: magnetorheological, pneumatic and hydraulic. The magnetorheological smart knee joint achieves the effect of adjusting the damping by changing the current to change the magnetic field strength. However, the viscosity of the magnetorheological fluid is closely related to the magnetic field, and the requirements for the magnetorheological fluid material are very hi...

AI Technical Summary

Problems solved by technology

The magnetorheological smart knee joint adjusts the damping effect by changing the current to change the magnetic field strength, but the viscosity change of the magnetorheological fluid is closely related to the magnetic field, and it has high requirements on the material of the magnetorheological fluid, which is not easy to control and is not easy Increase production capacity

Both hydraulic pressure and air pressure use a microprocessor to drive the motor to adjust the valve opening of the damping cylinder, so as to achieve the purpose of adjusting the damping, but the stability of the pneumatic knee joint support performance is not reliable, which is likely to cause safety accidents

[0003] At present, there are few structural designs for intelligent knee joint hydraulic damping cylinders in China. Related technical documents include: Patent No. 105769395A and Patent No. 106726028B both propose electronically controlled hydraulic damping cylinder structures for intelligent knee joint prostheses, but there are The shafts of the motor, the regulating valve body and the piston are in a straight line and are connected or in contact with each other, so that the motor receives a large axial load during the operation of the knee joint. During the adjustment process, it is easy to lose step and fail to reach the specified position, which seriously affects the knee joint. Performance issues with joint damping adjustments

Although the electronically controlled hydraulic damping cylinder structure proposed by Patent No. 106539633A avoids the problem of excessive axial load on the motor, the hydraulic flow path in the piston block is complicated and difficult to process

Patent No. 102065799A discloses a semi-driven prosthetic knee joint device, which realizes driving and non-driving modes through hydraulic pumps and damping adjustment valves, but the hydraulic valve circuit is very complicated, and the hydraulic pump and electric motor make the structure complex and heavy

Patent No. 201370655 and Patent No. 107035808A, although these two patents realize the separate adjustment of flexion and extension, but need two motors to control the corresponding valves, which makes the volume and weight larger and power consumption increased

Patent No. 109806036A realizes a motor to realize the two-way control of hydraulic damping, but the clearance fit between the designed valve body and the adjusting seat will lead to the formation of oil film in the gap for a long time, and the tension generated by the oil film will make the damping of the valve body too large when it rotates and the rotation will not rotate. Smooth, damping adjustment is not accurate.

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