Precision stopping and starting in milliseconds
Carlson’s Model UBSPC5 is a totally enclosed, single position air applied clutch that becomes a torque limiter when an overload condition exists on the driven side of the clutch. The UBSPC5 has a torque rating of 650 in/lbs @ 80 PSI. When air enters the bearing mounted, stationary air chamber of the clutch, the piston pushes a set of ball bearings into a special pattern that is designed into the hub and backplate. This engages the clutch in a specific position. If there is an overload, and the force of that overload is
significant enough to overcome the force in the clutch air chamber, the clutch will disengage. Reengagement of the clutch, after the overload has been cleared, occurs when air is again introduced into the air chamber. The clutch picks up the load of the application at the exact same place that it disengaged.
In this bakery application, the clutch needs to have a high starting torque, and a lower running torque, so a two stage air system is used to raise and lower the torque of the clutch. A proximity sensor tells the PLC when the clutch has disengaged, and the system stops within milliseconds, protecting the power transmission components from damage.