System and method for providing a more reliable interconnection between a spring and a brake shoe in the counterbalance system of a tilt-in window

摘要

An assembly of components that are use in a counterbalance system for a tilt-in window. A coil spring of wound ribbon is provided that has a shaped head. A brake shoe housing is provided that connects to the coil spring in such a manner that fatigue stresses are reduced in the coil spring as the tilt-in window is operated. The brake shoe housing has a receptacle slot formed into one of its side surfaces. An open relief is formed immediately above the receptacle slot. The open relief abuts against and supports the ribbon of the coil spring just behind the shaped head. By engaging the shaped head of the coil spring and supporting the coil spring adjacent to the shaped head, stresses experienced by the shaped head are greatly reduced. The result is a coil spring that has a much longer service life.

主权项

1. An assembly for use in a counterbalance system of a tilt-in window, said assembly comprising:
a coil spring of ribbon having a free end, wherein said ribbon terminates with a shaped head proximate said free end, and wherein said shaped head extends a first length along said ribbon; a brake shoe housing having a face surface, a rear surface, a bottom surface, a first side surface, and a second side surface, wherein said first side surface and said second side surface extend between said face surface and said rear surface at opposite sides of said brake shoe housing; a cam opening disposed within said brake shoe housing, and wherein said cam opening has a center point a first distance above said bottom surface of said brake shoe housing; a receptacle slot formed into said first side surface of said brake shoe housing at a distance from said bottom surface of said brake shoe housing no greater than said first distance, wherein said receptacle slot receives said shaped head of said coil spring; and a relief formed in said first side surface above said receptacle slot, said relief extending along said first side surface of said brake shoe housing for a second length that is at least as long as said first length, wherein a third length of said ribbon, adjacent said shaped head, extends through said relief and is supported by said first side surface as said shaped head is received within said receptacle slot, wherein said receptacle slot and said relief combine to form an anchor structure for said coil spring that engages both said shaped head and a section of ribbon adjacent the shaped head.