Patent Number: 6,253,644

Title: Torque wrench

Abstract: A torque wrench interfaces with a one or more fasteners intended to be tightened or loosened and includes a main housing with two or more preset torque devices which establishes a torque range insuring that the fasteners will not be tightened neither too tight nor too loose. A drive shaft protrudes from the main housing and rotatably drives a drive gear disposed in the main housing in which when rotated, drives the geared torque devices positioned on either side of the drive gear. A helical spring connects two torque pistons and adjustably applies a regulated torque to the driven torque piston in response to movement of the drive torque piston. The torque pistons are in a torque piston casing and are connected by irregular opposing surfaces urged together by the helical spring that allow for the torque pistons to rotate in relation to each other in one rotational direction only and allows the preset torque device to be enabled only when tightening a fastener in the clockwise direction. When the torque device is turned in the counter clockwise direction the surfaces lock together disabling the preset torque limit allowing the fastener to be loosened regardless to how much torque is applied to the fastener.

Inventors: Duquette; David M (San Jose, CA)

Assignee: Duquette; David M.

International Classification: B25B 23/142 (20060101); B25B 23/14 (20060101); B25B 17/00 (20060101); B23P 19/06 (20060101); B25B 013/00 ()

Expiration Date: 07/03/2018