A kind of grinding method of boron carbide air bearing

Abstract

The invention particularly relates to a precision grinding device and method for a boron carbide gas bearing. The grinding device comprises a positioning seat, a compression nut, a positioning ring and an elastic check ring. A limiting protrusion used for being clamped on a grinding machine chuck and an external thread which is used for being connected with the compression nut are arranged on the outer wall of the positioning seat. A positioning ring bearing assembly is mounted in an inner hole of the positioning seat. A circular groove is arranged in the inner hole of the positioning seat. The elastic check ring is mounted in the circular groove. The boron carbide gas bearing to be machined is mounted on the inner wall of the positioning ring, and the two end faces of the positioning ring are in close fit with the elastic check ring and the compression nut respectively. The method of the grinding device comprises the steps of first mounting, second inner hole grinding of parts to be machined, third online repairing of an inner hole grinding diamond grinding wheel, fourth end face grinding of the parts to be machined, fifth online repairing of end face grinding diamond grinding wheels, and sixth disassembling after part machining. When the grinding device and method are used for machining boron carbide materials, the machining precision is high, and operation is convenient.

Description

technical field [0001] The invention belongs to the technical field of precision machining, and in particular relates to a grinding method for a boron carbide air bearing. Background technique [0002] The boron carbide air bearing part is a hollow cylinder structure, the material is boron carbide ceramics, the bearing air bearing working surface is the inner hole and two end faces, the coaxiality between the inner hole and the outer circle is required to be Φ0.0015mm, and the two ends are respectively The verticality of the inner hole is Φ0.0005mm, the axial and radial dimension accuracy is 0.001mm, and the surface roughness value is Ra0.05μm. Since the ultra-high hardness of boron carbide is second only to diamond and cubic boron nitride, the main processing method is to use diamond abrasives for grinding and grinding, and because boron carbide has the characteristics of low fracture toughness and high brittleness, it can be used in grinding When cutting, a small cutting ...

AI Technical Summary

Problems solved by technology

Since the ultra-high hardness of boron carbide is second only to diamond and cubic boron nitride, the main processing method is to use diamond abrasives for grinding and grinding, and because boron carbide has the characteristics of low fracture toughness and high brittleness, it can be used in grinding When cutting, a small cutting amount must be used, so the processing efficiency is low

[0003] Usually, the grinding process of the boron carbide air bearing is: directly use the chuck of the grinding machine or use the elastic chuck to clamp the outer circle of the boron carbide air bearing, and then grind the inner hole and both ends of the bearing. It is necessary to re-clamp multiple times to measure the axial dimension of one end face or remove the part. However, the repeated positioning accuracy of this clamping method is not high, so it is difficult to achieve the above-mentioned accuracy indicators through grinding, and manual grinding is required to achieve the accuracy.

[0004] Moreover, during the grinding process of the inner hole and end face of boron carbide air bearing parts, the diamond grinding wheel cannot be trimmed online. It is necessary to disassemble the diamond grinding wheel from the grinding machine and then trim it. The machining accuracy and surface roughness of boron carbide material bearing parts cannot meet the requirements of use, which affects the machining accuracy and efficiency of parts

[0005] It can be seen that the inner hole and both ends of the boron carbide air bearing parts are ground by the usual clamping and positioning method, because the grinding process requires multiple clamping of the boron carbide air bearing, as well as multiple loading, unloading and trimming Diamond grinding wheel, it is difficult to achieve the required size and shape accuracy

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