Gas-film stepless variable damping device of gas static-pressure main shaft

Abstract

The invention provides a gas-film stepless variable damping device of a gas static-pressure main shaft. According to the device, a shaft sleeve and a main shaft are coaxially installed, a gas film isformed between the shaft sleeve and the main shaft, an air chamber outer sleeve is sleeved on the outer wall of the shaft sleeve, a plurality of protruding contact parts are uniformly distributed on the inner wall of the air chamber outer sleeve in the circumferential direction, a plurality of air chambers which are uniformly distributed in the circumferential direction are defined on the outer wall of the shaft sleeve, the air chambers communicates with an air film through throttling holes, through air inlet holes are formed in the wall surface of the air chamber outer sleeve where the air chambers are located, the air inlet hole is connected with an outlet of a T-shaped three-way ball valve through an air supply pipe, an inlet of one end of the T-shaped three-way ball valve is connectedwith an air source, an inlet of the other end of the T-shaped three-way ball valve is connected with an outlet end of a pressure reducing valve, an inlet end of the pressure reducing valve is connected with a neon gas tank, one end of a differential pressure sensor is connected with an air channel, the other end of the differential pressure sensor is connected with a neon gas circuit, displacementsensors are arranged outside the main shaft in a spaced mode, the two displacement sensors are arranged at 90 degrees by taking the axis of the main shaft as the center, the differential pressure sensor and data output ends of the displacement sensors are connected with a control system, and the control ends of the T-shaped three-way ball valve and the pressure reducing valve are connected with the control system.

Description

technical field [0001] The invention relates to a gas static pressure spindle air film stepless variable damping device. Background technique [0002] Gas hydrostatic spindle is the core component of ultra-precision machine tools, and its static and dynamic characteristics determine the processing performance of the machine tool to a large extent. During the machining process, the spindle will be affected by the cutting force from different directions and the periodic torque fluctuation of the motor, which will cause the spindle to generate motion errors and high-order harmonic vibrations in different directions, and it is prone to "unstable" phenomenon of the spindle operation. The stiffness and damping of the air film of the aerostatic spindle are the key factors to determine the dynamic characteristics of the spindle, so the control of the air film damping and stiffness is particularly important. In the prior art, the feedback control of the non-uniform force on the spin...

AI Technical Summary

Problems solved by technology

The air film damping is low, and the spindle is approximately forced to vibrate under external excitation. By mixing high-damping gas with air, the air film damping is increased, thereby improving the dynamic characteristics of the spindle. However, if the air film damping is always kept too high, it will produce The large shear force causes serious heating of the spindle, so it is necessary to adjust the air film damping

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