Method of manufacturing a spring hinge

Abstract

A plug is offered to make relatively easy and simple the assembly and pre-torquing of a spring-loaded hinge for doors and the like. These hinges comprise a pair of hinge leaves, each leaf defining at least one hollow hinge knuckle aligned with a hinge knuckle defined on the opposite leaf. Through the knuckles, a bi-ended torsion spring mechanism is inserted. A first plug is affixed within one hinge knuckle and engages one end of the torsion spring mechanism. At the opposite knuckle and second spring end, the novel second plug is affixed. This second plug includes a spring-engaging finger and a capstan body adapted to fit snugly within the knuckle. Atop the capstan body is a removable head which can be grasped by a wrench or like torsioning device. After this second plug is inserted in the hinge, the spring end is grasped and torqued by rotating the plug. When the plug and spring are torqued to a predetermined amount, a cross pin is inserted through the adjacent hinge knuckle and capstan body so as to affix the plug in the knuckle. Thereafter increased torque is applied to the plug head, which shears a plane of frangible material interconnecting the plug head and plug capstan, and permits plug head removal. After the head is removed, a covering cap can be inserted into the hinged knuckle at the spot from which the plug head was removed to provide a finished hinge appearance and to inhibit alteration of the correctly set hinge torsional-force-applying capability.