| 摘要 |
<p>A strip feeder particularly for punch dies comprises drive and idler rollers engageable with opposite faces of the strip being fed, a spring-loaded member displaceable in a first direction during the foward stroke upon receiving an impact and returned by the spring during the return stroke, a first one-way clutch effective to decouple the drive roller from the displaceable member during the forward stroke and to couple same during the return stroke, and a second one-way clutch effective to couple the idler roller to the fixed frame during the forward stroke and to decouple same during the return stroke. The described one-way clutch comprises a first member having an external annular surface and a second member including an internal bore for rotably receiving the latter. The second member further includes a cylindrical cavity terminating at its inner end in a small opening communicating with the bore, the axis of the cavity being at an acute angle with respect to a line tangent to the bore at the center of the opening. A displaceable wedging element is disposed within the cavity and has a nose projectable through the opening, the wedging element being biassed by a spring to permit relative rotation between the two members in one direction but to block same in the opposite direction.</p> |
