Alliedsignal Inc.

Robert Boschgmbh

Robert Bosch Technology Corporation

Neil J Clark

Thomas Edwin Demoise, Jr

Steven B Conger

Ralph G Kuskye

A disc brake having a ball-in-ramp actuator retained in a caliper for supplying a piston with a static clamping force to move first and second friction members into frictional engagement with a rotor to effect a parking brake application. The clamping force is transmitted from the ball-in-ramp actuator into the piston through an adjustment screw mechanism. The disc brake being susceptible to a thermal expansion and a thermal contraction and as a result the effect of the clamping force applied to bring the first and second friction members into engagement with the rotor may change during a time period that the parking brake application is initiated until it is terminated. The adjustment screw mechanism is characterized by a spring that is compressed by the actuation force to initiate the parking brake application that expands and contracts to compensate for the thermal contraction and expansion of the disc brake such that the effect of the static clamping force remains substantially the same for the duration time of the parking brake application.

Parking brake

A brake pad (10) having a mechanical joint formed between a friction member (22) and a metal backing plate (12) by a plurality of rivets (30,30' . . . 30.sup.n). Each rivet (30) has a head (36) and an end (37) with the head (36) engaging the friction member (22) and the end (37) engaging the backing plate (12). During assembly of each rivet (30) with the backing plate (22), a force is applied to the head (36) causing the end (37) to flow in a groove (38) in a die (16) and form a flattened surface. The amount of the force applied to head (36) is limited to create a clamping force between the head and backing plate which holds the friction member (22) against the backing plate (12) and yet noise developed through vibration during a brake application is attenuated as the friction member (22) and metal backing plate (12) vibrate at different frequencies.

Method of manufacturing a friction member

A method of manufacturing a brake pad wherein a clamping force of a mechanical joint formed between a friction member and a metal backing plate by a rivet is specified and controlled such that noise developed during a brake application through vibration is attenuated as the friction material and metal backing plate vibrating at different frequencies.

An anti-rattle spring (11) is mounted in a backing plate (31) of one a pair of opposed backing plate and friction pad assemblies 15 in a generally planar parallel relationship with a rotor (17) engaging friction surfaces and stationary torque support members (19,38). The spring (11) comprises a base portion (21) disposed in a plane which is generally parallel to the planes of the friction surfaces. The base portion (21) is fastened to one of the pads (15) through an elongated boss (39) in backing plate 31 and a corresponding hole (45) in the backing plate (31). The relationship between the elongated hole (45) and boss (39) prevents the anti-rattle spring (11) from rotating on the backing plate 31. The spring (11) also includes a web portion (23) which extends generally perpendicularly from the base portion (21) and a U-shaped resilient cantilevered blade (25) which extends from the web portion (23). The curved blade ( 25) has a free end (27) which engages the torque support member (19) to provide a resilient biasing between the torque support member (19) and the pad (15). The curved resilient cantilevered blade (25) extends initially from the web portion (23) in a direction away from the torque support member (19) and is subsequently curved back toward and into engagement with the torque support member (19). There is also a relatively flat resilient cantilevered blade (29) extending generally orthogonally from the base portion (21) in a direction opposite the web portion (23). This blade (29) will engage the brake rotor (17) during brake operation only if the thickness of the friction material of the outer brake assembly (15) is less than a predetermined thickness, thus providing an audible wear-limit warning.

Growing community of inventors

Granger, IN, United States of America

Neil J Clark