AUTOMATIC PRE-LOAD CONTROL SYSTEM BY CENTRIFUGAL FORCE FOR THE MAIN SPINDLE OF MACHINE TOOLS

摘要

An automatic pre-load control system for the main spindle of machine tools by centrifugal force is provided to control pre-load applied in a main bearing automatically according to the change of centrifugal force by including a spring, a main bearing and a sub bearing in a portion of a housing. An automatic pre-load control system for the main spindle of machine tools by centrifugal force comprises: a main bearing(120) and a sub bearing(160) equipped in a main shaft(110); and a spring(300) installed at a housing(100) equipped in the outer side. The main bearing comprises a main electromotive body(150) inserted between a main outer wheel(130) and a main inner wheel(140). The sub bearing comprises: a pair of sub inner wheels(180); and a centrifugal body(400) equipped between the sub inner wheels.