摘要 |
An improved coil spring counterbalance assembly embodying a coil spring support structure that provides a cooperatively radiused restraining shoe against which the uninterrupted smooth external circumferential surface of the coil spring ribbon rotationally operates in extension and retraction thereof during counterbalanced sash movement, thereby eliminating both the clicking sound and spring rotational cyclic vibrational shocks otherwise caused by the spring interior ribbon core tail ending riding over the top of a spring core support hub, in addition to a multiple coil spring connection method for improved successive affixment of extended coil spring ribbons one to the other and in turn to the sash attached balance shoe connector therefor when more than on coil spring is required in order to effect proper sash counterbalancing.
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