Patent ID: 7033247

Claim:
An electric sharpener, comprising: (a) a main frame; (b) a main shaft and a motor with an output shaft mounted on the main frame; (c) a transmission wheel fixed to the main shaft; (d) a grinding stone mounted on the main shaft; and (e) a cantilever type tool rest fixed to the main frame, said tool rest having a general shovel clamp which includes: (1) a base plate having a plurality of threaded bores formed therethrough; (2) a plurality of knobs each having a threaded lower portion engaged in a corresponding threaded bore of the base plate; (3) a pressing plate mounted between a shoulder portion of the knobs and the upper surface of the base plate; and (4) a plurality of compressing springs each surrounding the threaded lower portion of a corresponding knob between the pressing plate and the base plate; wherein the base plate includes right and left supports protruded downwardly from it, each of the right and left supports having a through hole for mounting the clamp to the tool rest; wherein the motor is mounted on an angular frame having two legs, the end of each leg being provided with a mounting hole through which a pivot shaft is inserted, the pivot shaft being pivotably mounted on the main frame, so that the motor may pivot about the pivot shaft; and wherein the output shaft of the motor, owing to its weight, is pressed against the periphery of the transmission wheel so as to drive the transmission wheel by friction force.