It’s a mechanical devices, which can transmit the torque in one direction only and in other direction it is free. In torque transmitting direction, sprag cage is engaged between inner & outer. And in opposite direction, it is free between inner & outer.
Mostly use in dual drive system. Main drive & auxiliary drive. For etching
or in idle condition,auxiliary drive is running. At this time, over running
clutch is working as simple coupling and transmit the torque. While start the
main drive, outer race is over run due to faster rotation
Benefit of over running clutch
In material handling system, like conveyor & bucket elevator, mostly used the
hold back devices integrated to gear box. During the power cut off or suddenly
power failure, inclined conveyor or bucket elevator tends to rotate in reverse
direction with high speed due to gravitational force. To prevent the reverse
motion, Holdback/Backstop used. As name suggest – Hold to run on back or stop to
run on back
In Hold back devices, it is made of 3 part
Outer race – Fixed with gear box body
Inner race – mounted on the gear box extended shaft
Sprag cage – it is part which can perform action. Design of the sprag cage like that, during the normal direction, due to centrifugal force, it is free between Outer race & Inner race and while rotate in reverse, sprag cage generate clamping force.
Benefit of hold back devices
In any conveyor or other system which is running by dual or triple drive, at that time, external holdback/backstop is useful for robust design & high torque transmitting capacity
Benefits of external holdback/backstops
Indexing free wheel transmits a back and forth motion into a steeped
rotation.
In forward direction it is transmitting the torque and in back direction it is
free.
Our Cam Clutch products are designed to transmit torque in one
direction of
rotation and overrun in the opposite direction of rotation. All
Tsubaki Cam
Clutch products utilize the same principle of operation. We
offer various series
of Cam Clutch products to address the many types of applications
where they are
most often used.