Patent ID: 7647805
Filing Date: 2010-01-19
Classification: B21D

Abstract:
1. A detachable metal sheet bend angle adjustment assembly comprising: a lifter plate having a tapered bottom face and a through hole with a middle chamber; a wedge plate having a tapered top face, a bottom face, a front side face defining a side recess and a rear side face opposite the front side face, a support plate; an upper positioning frame having a rotary dial with an adjustment screw, a pushing coil spring, and a ring spring installed within the middle chamber of the through hole in the lifter plate, wherein the bottom face of the wedge plate is slideably mounted to the support plate, such that the tapered top face of the wedge plate is in apposition to the tapered bottom face of the lifter plate and the side recess is configured to receive the adjusting screw of the upper positioning frame such that clockwise rotation of the adjusting screw advances the wedge plate and lifts the lifter plate and counterclockwise rotation of the adjusting screw in a second direction retracts the wedge plate and lowers the lifter plate, and wherein the pushing coil is configured to engage the rear side face of the wedge plate opposite the rotary dial such the elasticity of the pushing coil spring counterbalances the force generated by the rotation of the adjusting screw.