Novel preload regulation device for high-speed motorized spindle bearing

Abstract

The invention discloses a novel preload regulation device for a high-speed motorized spindle bearing. The novel preload regulation device comprises a shaft shoulder, a front bearing, an outer ring spacer, an inner ring spacer, a rear bearing, a spindle and a locking nut, wherein the front bearing and the rear bearing are isolated by the inner ring spacer and the outer ring spacer to be arranged on the spindle in a sleeving manner, one ends of the front bearing and the rear bearing prop against the shaft shoulder, and the other ends of the front bearing and the rear bearing are locked by the locking nut; the inner ring spacer and the outer ring spacer are made of materials quite different in linear expansion coefficients, the linear expansion coefficient of the inner ring spacer is larger than that of the outer ring spacer, the axial length of the inner ring spacer is smaller than that of the outer ring spacer under the normal temperature, in a high-speed rotation process of the motorized spindle, the temperature raises, the axial elongation of the inner ring spacer is larger than that of the outer ring spacer along with the raising of the temperature, the length difference of the two ring spacers is smaller than a length difference delta in an initial pre-tightening process, and the extrusion force to a rolling body is reduced, so that the pre-tightening force is reduced in the high-speed rotation process, the heating amount of the bearing is reduced, and the service life of the bearing is prolonged. The novel preload regulation device is simple and practical and can be used for effectively regulating the pre-tightening force of the bearing without basically changing a spindle structure.

Description

technical field [0001] The invention relates to a novel high-speed electric spindle bearing preload adjustment device, which belongs to the field of electromechanical engineering. Background technique [0002] Angular contact ball bearings are commonly used supporting components for high-speed electric spindles of machine tools. In order to increase the rigidity of the spindle, reduce running noise, improve the machining accuracy of the shaft, and compensate for the clearance caused by the wear and settlement of the bearing configuration during operation, the bearing must be preloaded. force. For precision machine tools, the pretightening force of the spindle bearing should be adjustable so that it can approach the corresponding optimal state under different working conditions. [0003] The optimal pretightening force of machine tool spindle bearings is related to the bearing speed, temperature rise and other factors. During the operation of the bearing, as the rotational ...

AI Technical Summary

Problems solved by technology

The existing preload self-adjustment methods can be divided into two categories: one is to change the bearing structure and adopt the principle of preload compensation to achieve it. The size of the pre-tightening force; the other is to control the pre-tightening force through piezoelectric elements. These two methods may change the bearing structure, affect the performance of the bearing itself, or are more complicated, so there are great limitations in practical applications.

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