Drum Brake S-Cam Having Offset Cam Followers

摘要

A drum brake is provided that improves the direction of the actuating forces to reduce stress, improve efficiency and permit thicker brake linings. First and second brake shoes each have a first end pivotally coupled to a brake spider. First and second cam followers are disposed at corresponding second ends of the brake shoes. A cam engages the cam followers with movement of the cam causing the brake shoes to move between positions of engagement and disengagement with a braking surface. The cam followers are offset such that a center of the first cam follower is disposed at a first distance from a center axis of the brake and a center of the second cam follower is disposed at a second distance from the center axis with the first distance different from the second distance so as to improve the direction of the cam force vector.

主权项

1. A brake, comprising:
a brake spider having a central aperture configured to receive an axle extending therethrough along a center axis of the central aperture; first and second brake shoes, each of said first and second brakes shoes having a first end pivotally coupled to said brake spider; a first circular cam follower disposed at a second end of said first brake shoe; a second circular cam follower disposed at a second end of said second brake shoe; and, a cam in engagement with said first and second circular cam followers, movement of said cam causing said first and second brake shoes to move between positions of engagement and disengagement with an associated braking surface wherein a center of said first circular cam follower is disposed at a first distance from said center axis and a center of said second circular cam follower is disposed at a second distance from said center axis, said first distance different from said second distance.