Patent ID: 9289878
Filing Date: 2016-03-22
CPC Classification: B24B,F16H,Y10T

Claim Text:
1. A grinder comprising: an arbor configured to rotate about a first axis, the arbor being configured to support a grinding wheel for rotation therewith; a gear surrounding a first portion of the arbor and having a slip fit with the first portion of arbor; a motor configured to supply rotation to a drive train including the gear; a collar surrounding a second portion of the arbor and having an interference fit with the second portion of the arbor such that the collar is constrained for rotation with the arbor about the first axis; at least one spring disposed between the gear and the collar, the at least one spring configured to exert a biasing force along the first axis such that one or more resulting friction forces cause the arbor to rotate with the gear when a torque exerted on the gear is less than a threshold torque; and a spindle lock hub surrounding a third portion of the arbor, the spindle lock hub being constrained for rotation with the arbor about the first axis, the first portion of the arbor being located between the second and third portions of the arbor.