| 摘要 |
There is disclosed a clutch which will release under overload and will reset automatically upon speed reduction of the driving element. Two radial bars are fixed to the driven shaft; a driving wheel is rotatably mounted on the driven shaft adjacent the bars, and pivotally carries a pair of diametrically-opposite elongated pawls biased by tension springs to a radially-inwardly-extending position within the driving wheel to engage the respective arms, whereby the driving wheel drives the driven shaft. Under overload, the arms cause outward pivotal movement of the pawls against the bias of the springs, whereby the arms are cleared by the pawls, which remain in outwardly-pivoted position under centrifugal force until speed reduction of the driving wheel. In a preferred embodiment, the center of gravity of the pawls, in their bar-engaging position, lies on the leading side of a straight line passing through the shaft axis and the pawl pivotal axes, whereby the centrifugal force exerted on the pawls assists the coil springs to keep the pawls in bar-engaging position and therefore permitting the use of springs with a smaller tension force, resulting in a smoother resetting of the clutch.
|
