| 摘要 |
<p>A variable ratio drive employs an elastic extensible control belt which changes its cross-section in relation to induced changes in its length, according to Poisson's ratio. The control belt is introduced between a pulley and a drive belt, and a mechanism employing a gear head control motor, or the like, acts to change the length of the control belt in a precise manner. This in turn changes the thickness of the control belt in a precise way, and the effective radius of the pulley/ control belt, acting on the drive belt, operates to change the ratio of the pulley and drive belt system. A specific embodiment is disclosed in a lightweight video tape recorder, used to change the drive ratio between a motor and a tape transport capstan, according to control signals.</p> |
