Bidirectional rotary brake

A bidirectional brake comprising:

• a. housing means;
• b. rotational shaft means which are supported within the housing means and which have an input end and an output end;
• c. braking plate means which are connected to the shaft means for rotation therewith;
• d. a roller assembly which is supported within the housing means and which includes a planar member which is rotatable about a first axis, the roller assembly further including roller means which are connected to the planar member such that an axis of rotation of the roller means is generally parallel to the planar member and forms an acute angle with an imaginary radial line extending from the first axis to a circumferential edge of the planar member;
• and
• e. means for moving the braking plate means into engagement with the roller assembly when a reverse or overrunning load is applied to the output end of the shaft means, in a manner that the braking plate means engages the roller means thereby generating a first force component which is normal to the roller axis of rotation and which rotates the roller means, and a second force component which is directed along the axis of rotation of the roller means for generating frictional drag to limit the rotation of the braking plate and the shaft means connected thereto.