| 摘要 |
A blade punch for forming teeth in a connector plate, the blade punch comprising an elongated blade having a metal working tip at one end and a shank at the other end. The blade has an elongated cross-section defined by opposing parallel spaced planar side walls and opposing ends. Each end comprises a major end wall and a minor end wall which converge to end wall intersections, where the end wall intersections are eccentric to a plane parallel to and midway between said side walls. Each end wall intersects a side wall at an obtuse angle. The metal working tip has opposed air cut faces abutting one another along an air cut edge and opposed first and second forming faces, each of the forming faces abutting one of the air cut faces along an exterior edge. Each of the air cut faces is bordered by a portion of one of the minor end walls, a portion of one of the side walls, the air cut edge, and one of the exterior edges. Each of the forming faces is bordered by a portion of one of the major end walls, a portion of one of the minor end walls, a portion of one of the side walls, and one of the exterior edges. A forming angle between 50 DEG and 60 DEG is formed between the first forming face and the exterior edge bordering the second forming face in a plane normal to the first forming face. |
