Centrifugal backspin brake

摘要

A centrifugal brake system for retarding shaft backspin includes a brake drum, a brake hub attachable to the shaft and two or more brake shoes mounted on the hub for braking engagement with the drum. A mechanical linkage transfers the generated braking force from the brake shoes to the hub and permits radial displacement of the brake shoes relative to the hub, upon rotational shifting of the hub relative to the brake shoes between deactivated and activated positions. In the deactivated position of the hub, the brake shoes are maintained in a radially inward, disengaged position. In the activated position, the brake shoes are radially displaceable by centrifugal force from the disengaged position to a radially outward, engaged position, wherein the brake shoes are in braking engagement. The rotational shifting of the hub is achieved through frictional drag between the brake shoes and the brake drum.

主权项

1. A centrifugal brake system for retarding backspin of a shaft comprising:
a brake drum for mounting in a stationary supporting structure concentrical with the shaft; a brake hub attachable to the shaft for co-rotation with the shaft concentrically in the brake housing; two or more brake shoes distributed circumferentially about the hub and mounted on the hub for selective braking engagement with the brake drum; a mechanical linkage for transferring braking force generated by the braking engagement from each of the brake shoes to the hub and for radial displacement of the brake shoes relative to the hub, upon rotational shifting of the hub relative to the brake shoes, between a radially inward, disengaged position, wherein the brake shoes are not in braking engagement with the brake drum and a radially outward, engaged position, wherein the brake shoes are in braking engagement with the brake drum; and means for generating a frictional drag between the brake shoes and the brake drum to cause the rotational shifting of the brake hub relative to the brake shoes to the deactivated position during forward rotation and to the activated position during backward rotation wherein each brake shoe has first and second ends located on opposite sides of the respective mechanical linkage and wherein each brake shoe is pivotable about the mechanical linkage, and the means for generating a frictional drag is a biasing means connected to each brake shoe for pivoting the brake shoe about the mechanical linkage and biasing the first end of the brake shoe against the brake housing for generating a friction force between the brake shoe and the brake drum.