Abstract: 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 the same or different anchor pins on 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 distances between the centers of the first cam followers and the anchor pin or pins supporting the brake shoes differ so as to improve the direction of the cam force vector.
Abstract: A drum brake (10) is provided which has a pair of brake pads (12), each pad being moveable generally radially outwardly into contact with a brake drum by a respective operating lever (14) which is acted on at one end by a brake applying means (15) and pivoted (16) at the other end from a backplate (11). Each pad is contacted by a portion (14c) of the respective operating lever intermediate the lever ends and is moved radially outwardly between a pair of circumferentially spaced abutments (45) which extend generally perpendicular to the backplate (11) and which react braking torque when the brake is applied. The required pad to drum clearance is established by knock-back of the drum on the pads (12).
Abstract: Brake apparatus includes a transmission unit for operatively connecting a brake pedal to a master cylinder, and the transmission unit is a mechanism capable of varying a ratio between an output amount of a push rod connected to a master cylinder and an operation amount of the brake pedal. Further, the transmission unit is constructed in such a manner that, in an initial operation region of the brake pedal, a ratio of the operation amount of the brake pedal to the output amount of the push rod is set to be greater than in another operation region immediately following the initial operation region.
Abstract: A drum brake device is disclosed to provide a smooth returning of the brake shoe when the service brake is operated before the vehicle starts on a slope, in which a circumferential edge of the linings 6, 6 of the brake shoes 2, 3 at the service brake actuator 8 side nearest the first adjacent ends is located on a line of action B of the service brake actuator 8 or at a point closer to the anchor than the line.