Energy-efficient hydraulic servo cylinders with bi-directional cushioning and precise force control

Abstract

The invention discloses a high efficiency hydraulic servo cylinder with bidirectional buffering and accurate force control. The high efficiency hydraulic servo cylinder with bidirectional buffering and accurate force control comprises a cylinder tube; a piston rod is arranged in the cylinder tube, and an inner cavity of the cylinder tube is separated into a rod cavity and a rodless cavity by the piston rod; the cylinder tube is provided with a rod cavity end electro-hydraulic servo valve and a rod cavity end accumulator connected with the rod cavity and a rodless cavity end electro-hydraulic servo valve and a rodless cavity end accumulator connected with the rodless cavity; and an inlet and outlet valve plate is arranged on the cylinder tube. The hydraulic servo cylinder is suitable for an occasion when the rod cavity and the rodless cavity of the cylinder tube are effective working cavity. When the cylinder is working, buffering and shock absorption can be realized, cylinder seals, electro hydraulic servo valves, pull pressure sensors and actuating objects can be effectively protected without damage; inlet and outlet flow of the servo cylinder can be effectively adjusted, internal and external pressure difference of an oil port can be reduced, and the cylinder high energy efficiency value; and dynamic stiffness can also be adjusted in real time, thus the controlled load can be quickly matched, a good dynamic performance can be performed, and accurate force control can be achieved.

Description

technical field [0001] The invention relates to a hydraulic servo oil cylinder. In addition to good two-way buffering and high-frequency servo actuation functions, the addition of double servo valves and double accumulators also enables it to have precise force control performance and high energy efficiency. It belongs to the technical field of hydraulic servo transmission. Background technique [0002] Hydraulic servo cylinders have the characteristics of large thrust, light weight, high integration, fast dynamic response, and high control precision, and are widely used in construction machinery, metallurgical machinery, ships, aerospace, robots and other fields. However, none of the existing hydraulic servo cylinders has the function of elastic buffering and overpressure protection, or only an accumulator with a micro-spring effect is installed in the single chamber to eliminate the pressure shock of the single chamber. Analogous to animal muscles and tendons, its superio...

AI Technical Summary

Problems solved by technology

Analogous to animal muscles and tendons, its superior stretching and contraction properties play a considerable role in energy storage and passive dissipation of impact force, while hydraulic oil is almost an incompressible medium, and its impact A large amount of energy is dissipated in the work process, and it is easy to cause huge instantaneous changes in internal pressure, and for symmetrical electro-hydraulic servo valves controlling asymmetrical hydraulic cylinders, the amount of oil entering and exiting the rod chamber and rodless chamber is different, which is bound to also cause excessive energy loss

Therefore, on the whole, due to the lack of comprehensive and effective pressure peak elastic buffering and timely flow control, it is very easy to cause hydraulic servo cylinder seals, electro-hydraulic servo valves, sensors or operating conditions under high operating frequency and high vibration shock conditions. Different degrees of damage to moving objects or greatly shorten their working life, on the other hand, it also reduces the operating efficiency of the system

[0003] Most of the existing servo cylinders use a single servo valve to control the flow of rod and rodless chambers, while the existing servo valves or proportional valves have low bandwidth and cannot maintain a stable variable stiffness effect in control, resulting in the use of The large interactive impact force generated by the foot or other motion platform as the driving source cannot be completely eliminated when it interacts with the outside world, and the actuation process is a "hard impact process", and the force control accuracy is poor.

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