Mounting arrangement for constant force spring balance

摘要

A mount for one or more constant force curl springs uses a mounting block secured within a sash shoe channel to support the underside of a lowermost curl spring with a superposed curl spring mounted to counterrotate against an outer convolution of the lowermost spring. Uncoiled free ends of the curl springs pass downward on opposite sides of the mounting block and connect to opposite sides of a sash shoe arranged below the mounting block. This connection is made by laterally sliding the spring ends into slots molded in the sash shoe so that barbs struck and bent from the planes of the free ends of the springs are lodged in widened recesses of the slots to retain the spring ends against upward withdrawal from the spring slots.