Patent ID: 6009764
Filing Date: 2000-01-04
Classification: G01L,G01M

Abstract:
A frequency discrimination type torque tester by rotating an outer race and an inner race of a ball bearing relative to each other and evaluating the quality of the ball bearing according to the degree of transfer of a torque applied to one race to the other, comprising:a drive source for applying a torque to either the outer race or the inner race of the ball bearing as a test sample and thereby rotating the race;a torque sensor for detecting torque induced on the other race to which the torque applied to one race is transmitted;filters for dividing the frequency band of an output of the said torque sensor into a plurality of desired bands wherein said filters include a high-pass filter for separating a spiky change component which is based on finishing accuracy of the race surfaces of the ball bearing or a dent or dust included in the bearing and which is short in terms of time, and generating an output signal of said component, and a low-pass filter for separating a gentle undulated change component based on deviation from roundness of the race surfaces of the ball bearing or rotational deflection, and generating an output signal of said component; andevaluating means for evaluating the quality of the ball bearing from said output signals provided from both filters.