Compound winding apparatus and counterbalance systems
First Claim
1. A compound counterbalance system for window sashes and the like comprising:
- biasing means for easing operation of a window sash and the like, the biasing means being movable at an inherently variable rate of force;
a first biasing force transmission means, connected intermediately of the window sash and the like and the biasing means, for increasing the effective range of movement of the biasing means; and
,a second biasing force transmission means connected intermediately of the window sash and the like and the biasing means, the second biasing force transmission means having a variable rate of operation predetermined to automatically compensate for the variability of the biasing means to provide substantial constancy of the biasing force.
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Accused Products
Abstract
A compound counterbalance system for window sashes and the like, comprising: a biasing mechanism for easing operation of a window sash and the like, the biasing mechanism being movable at an inherently variable of force; a first biasing force transmission, connected intermediately of the window sash and the like and the biasing mechanism, for increasing the effective range of movement of the biasing mechanism; and, a second biasing force transmission connected intermediately of the first biasing force transmission and the biasing mechanism, the second biasing force transmission having a variable rate of operation predetermined to automatically compensate for the variability of the biasing mechanism, to provide substantial constancy of the biasing force. The biasing mechanism preferably comprises a linearly extensible and contractible spring. In one embodiment, both the first and second biasing force transmissions comprise pulley and cable systems. In another embodiment, only the second biasing force transmission comprises a cable and pulley system and the first biasing force transmission comprises a reduction gear assembly. In each embodiment, the variable rate of the second biasing force transmission comprises a generally conical, spiral-grooved pulley and a cable means affixed at one end to the pulley, affixed at the other end to the biasing mechanism and adapted to wind into and out of the groove.
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Citations
25 Claims
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1. A compound counterbalance system for window sashes and the like comprising:
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biasing means for easing operation of a window sash and the like, the biasing means being movable at an inherently variable rate of force; a first biasing force transmission means, connected intermediately of the window sash and the like and the biasing means, for increasing the effective range of movement of the biasing means; and
,a second biasing force transmission means connected intermediately of the window sash and the like and the biasing means, the second biasing force transmission means having a variable rate of operation predetermined to automatically compensate for the variability of the biasing means to provide substantial constancy of the biasing force. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. A method for counterbalancing a load, comprising the steps of:
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exerting by movement a biasing force on the load against forces tending to retard movement thereof; compounding the biasing force with a compensating force at a variable rate predetermined to automatically compensate for characteristic variability of the biasing force to provide a substantially constant compound biasing force; and
,transmitting the substantially constant compound biasing force to the load through a mechanical system configured to increase the range of movement in which the biasing force is effective, whereby the effect of the biasing force is uniform. - View Dependent Claims (20)
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21. A compound winding apparatus, comprising:
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a generally conical, spiral-grooved pulley adapted to engage a first cable means windable into and out of the spiral groove at a variable rate as the pulley rotates; a drum adapted to engage the second cable means windable onto and off of the drum at a substantially constant rate as the drum rotates, the pulley and the drum being at least indirectly engaged to undergo simultaneous rotation; and
,mechanical means indirectly linking the pulley and drum for rotation at different speeds, the variable rate being predetermined to automatically compensate for inherent variation in a biasing force transmitted through one of the first and second cable means, whereby a substantially constant force is transmitted through the other of the first and second cable means. - View Dependent Claims (22, 23, 24)
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25. A compound winding apparatus, comprising:
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a generally conical, spiral-grooved pulley adapted to engage a first cable means windable into and out of the spiral groove at a variable rate as the pulley rotates; a drum adapted to engage the second cable means windable onto and off of the drum at a substantially constant rate as the drum rotates, the pulley and the drum being at least indirectly engaged to undergo simultaneous rotation; and
,a block and tackle means imparting a mechanical advantage in operation, having a movable end connected to the second cable means and a pulley-entrained cable having a free end which moves through a first range of movement larger than a second range of movement defined by the first cable means by a multiple related to the ratio of the mechanical advantage of the block and tackle means, the variable rate being predetermined to automatically compensate for inherent variation in a biasing force transmitted through one of the first and second cable means, whereby a substantially constant force is transmitted through the other of the first and second cable means.
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Specification