Patent ID: 7134951

Claim:
A holder to engage and hold tightly in place a sheet of abrasively-faced material, said holder comprising; a base plate having a flat bottom backing surface with a pair of parallel side edges, with a gripping surface adjacent to each side edge; a gripper adjacent to and extending along each of said side edges, said gripper comprising a cam plate mounted to an upper surface of said backing plate so as to be reciprocable normally to its respective side edge, each said cam plate including a downwardly-directed lip and including a cam slot so disposed and arranged as to react with a cam pin to move the cam plate and its lip toward and away relative to its respective side edge; an actuator comprising a rotor rotatably mounted to said base plate, a said cam pin being mounted to said rotor and inserted into each cam slot, and a handle for turning the rotor; whereby with the rotor in one position with the cam pins said cam slots positioning said cam plate to place its lip spaced from the respective flange to admit an edge of the sheet, the rotor can be turned to move the cam pins and cause the cam plates to move inwardly, with the flanges engages to the sheet, thereby drawing the edges of the sheet toward one another to tighten the sheet against the base plate.