Application

Ogura hysteresis/mag-particle slip clutch used to prevent gear breakage in paper handling machine. (Over-load clutch.)

Products Used

Ogura OPL-N (clutch with shaft) and OPL-R (hollow bore unit) series.

Size Used

In general .3 to 1.5.

Description of Operation

The feed roll is driven by the gear train. As it picks up paper, the OPL clutch delivers normal operating torque. (Torque in the OPL unit is a function of the magnetic particle powder and the number of ceramic magnets in each unit.) If a jam condition occurs the OPL clutch slips. The gear train continues to operate at normal rpm, but the feed roll is motionless because of the jam condition. Since the clutch slips the gear train is protected and does not break.

Reason for Selection of the Ogura OPL Clutches

Because they are hysteresis in function there is very little break away torque in an OPL clutch. In a normal friction type torque limiter there is a high degree of break away torque. Occasionally to accommodate the slip torque required the break away torque has to be so high that potential damage could still occur in the gear train. The OPL clutch eliminates this possibility from happening. With other friction torque limiters there are friction surfaces that wear. Because these surfaces wear torque repeatability is a problem. The OPL's operation is smooth regardless of life on the unit. The OPL unit is also totally enclosed therefore there is no friction debris that can contaminate the drive system. OPL units require no external power source to operate. They are preset for delivering a given torque and require no setup or adjustment.

Other Applications

Copy machines, fax machines, photo developing machines all have potential for OPL clutches. Anytime a film or paper could get into a jam condition, and that jam could cause other machine components to break, a slip clutch is desired. The Ogura OPL clutch has the advantage of supplying a consistent repeatable torque in a very cost effective package. These clutches are manufactured in high quantities and can provide the low cost per torque.