Wehr Corporation

Venturedyne, Ltd.

Wayne D Hendricks

The disclosure relates to an electromagnetic brake mounted to and used with electric motors. Such brakes have an 'E' shaped electromagnet mounted on a magnet support. An armature block is mounted on a plate and both the block and the plate move when the electromagnet is energized or de-energized. The improvement involves a magnet support of the cantilever type. Such support bends slightly when the electromagnet is energized so that the faces of the 'E' magnet legs can self-align and be maintained substantially parallel with the armature block. The preferred structure also includes a resilient pad interposed between the block and the plate and at least one stop limiting compression of the pad. A special bolt securing plate hold the armature block bolts in place.

Electromagnetic brake with improved magnet structure

A non-rotatable, axially movable control ring is connected to the ring on the clutch input through a thrust bearing to control engagement and disengagement of the clutch input with the output. The control ring is biased to the clutch disengaged position by springs which are weaker than those biasing a loading plate to a stop cancelling out of the loading spring force. Energization of the magnet coil fixed on the control initially causes movement of the coil towards the armature fixed on the loading plate. That causes the clutch to engage before the magnet air gap is closed. Therefore, the armature moves to the coil and this lifts the loading plate off its stop against the loading spring. When the armature engages the coil, the loading spring acting on the plate acts through the magnet to the control plate to load the clutch and determine torque capacity which is adjusted by adjusting the load on the torque spring.

Alternating current clutch

The compressed spring acting on one end of the lever urges the lever in the direction to apply force to a pressure plate guided by the fixed bushings to apply pressure to the brake pads and discs to prevent rotation of a motor shaft received in the coupling. When the solenoid coil is energized, the armature lifts the end of the lever to relieve the pressure and release the brake. If the plunger at the other end of the lever is depressed, the lever will tilt to release the brake and the brake will remain released as long as the plunger is depressed. The same spring which biases the plunger upwardly biases the plunger in a rotational sense so the plunger can be rotated against the bias of the spring and cause the projecting pin to work against the cam on the end of the lever to tilt the lever in the direction allowing the brake to release. If the pin passes over the hump on the cam, the brake will remain released until the plunger is manually returned to its original position or until the coil is energized long enough to lift the other end of the lever and permit the projecting pin to pass over the cam hump and return to its original position.

Growing community of inventors

Mukwonago, WI, United States of America

Wayne D Hendricks