Method of forming helical springs

摘要

The method of forming helical springs and the installation for carrying same into effect relate to manufacture of springs and can be used with particular advantage for the purpose of forming helical springs by winding hot bars on a rotating mandrel. According to the invention, the winding of the bar on the mandrel is effected in the plane of the bar feed by pressing the bar against the mandrel over part of the circumference thereof for the purpose of forming spring coils. Each formed coil is relieved of the forming pressure and moved by a predetermined amount to the free end of the mandrel in order to set the coil pitch. The installation for carrying said method into effect comprises a plurality of sectors mounted equidistantly round the mandrel, said sectors being adapted for moving radially for applying a pressure force to the bar and for making a traversing movement along the mandrel in order to pass under a bar guiding arrangement and a pitch setting arrangement comprised in the installation. The pitch setting arrangement has an arm located in the path of movement of the formed coil and designed for moving the coil towards the free end of the mandrel. This makes it possible to form springs of any pitch and to remove the spring from the mandrel as it is coiled.