Static-pressure gas bearing

Abstract

The invention relates to a static-pressure gas bearing comprising a cylindrical bearing body, a rotor rotatably arranged in the bearing body, a front cap fixed on a right side of the bearing body, and a back cap fixed on a left side of the bearing body. Threaded holes arranged coaxially with a back cap gas-ejection hole are provided on the back cap on the left of a back cap gas chamber. Gas outlets are arranged in the back cap along an axial direction of the back cap. Each threaded hole is provided with a screw. A rotor gas chamber is provided in the rotor. Radial gas outlets are arranged in the rotor along a radial direction of the rotor. An annular groove is provided on a peripheral wall of the rotor. An axial gas outlet is arranged on a left end of the rotor along an axial direction ofthe rotor. A round recess is provided on the left end-face of the rotor. During an operation process of a traditional gas bearing, only a radial air film is provided, direct contact of boundary solids can easily happen, and locking is caused, such that the bearing and a main shaft might be damaged. With the static-pressure gas bearing provided by the invention, the problem can be solved, and the bearing can work under both a radial load and an axial load.

Description

technical field [0001] The invention relates to the technical field of high-speed rotary machinery and ultra-precision instruments, and discloses a static pressure air bearing. Background technique [0002] The air bearing is a bearing that uses the viscosity of the gas to increase the pressure of the gas in the gap to suspend the shaft. It is a high-tech product developed rapidly in the middle of the 20th century. Air bearings rely on air lubrication. Compared with conventional oil-lubricated bearings (rolling bearings or oil-based sliding bearings), it has many good characteristics: the friction factor and friction torque are small, and the gas bearing can work in the cleanest state. It has the characteristics of cold working, the motion wear rate is almost zero, low noise, small vibration, high precision, long life, can work in a wide temperature range and harsh environment, and can maintain a small gap. Therefore, it is widely used in national defense, energy, machine t...

AI Technical Summary

Problems solved by technology

[0004] In the traditional static pressure air bearing, because the gas is continuously discharged from the outer edge of the bearing into the atmosphere, the air does not have boundary lubrication ability. During the working process, if the air bearing load exceeds the specified limit, direct contact with solids will occur immediately. And locked, resulting in damage to the bearing and the main shaft, and it can only bear radial load, it can not meet the requirements for the situation of both radial load and axial load

In addition, since the air contains particles, powder layers and other particles, when the air is pressed into the gap between the bearings, these particles are easy to deposit around the gas injection hole, and after a long time, the gas injection hole will be blocked, so that the gas cannot reach the bearing and the rotor smoothly. In between, the rotor cannot be balanced and floated, resulting in serious rubbing and vibration. When the rotor vibrates or local rubbing or external disturbance, the air pressure effect at both ends of the rotor is no longer equal, thus reducing the static pressure air bearing. load carrying capacity, which reduces the reliability of high-speed rotating machinery

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