Door closing spring - consists of pre-stressed torsion bar which holds door in closed position

摘要

The door closer is formed by a torsion bar spring (1) which fits inside a housing (2) and is screwed into a screw thread (4) in the lower part of the housing. The middle part of the torsion bar (1) is a clearance fit in an upper housing (3). The upper end of the torsion bar has splines (6) which fit in grooves in the conical element (5). This conical element has external splines which engage matching splines in the upper end of the upper housing. The lower housing is fixed to the doorpost and the upper housing is fixed to the door. A torsional stress is applied to the torsion bar (1) through the conical element (5) when it is vertically above the upper housing. USE - Door closing spring.