Abstract: A parking brake system includes an engine oil pressure switch normally controlling the activation of a parking brake. The controller is actuated to temporally ignore a communication from the engine oil pressure switch so that the brake may be released even when the engine is disabled.

Abstract: A caliper brake (10) is adapted to act upon a stator (40) to engage a rotor of a vehicle. A housing (11) carries both a spring applied hydraulically released piston assembly (12) and a pressure intensifying piston assembly (14). The assemblies (12, 14) are in fluid communication with each other. The assembly (12) includes a piston (18) and a spring assembly (20) which urges the piston (18) into a first position engaging the stator (40). The piston assembly (14) includes a pressure intensifying (PI) piston (64) which is in a first position when the piston (18) is in the first position. When the PI piston (64) moves from a first position to a second position, the fluid acts upon the piston (18) thereby disengaging the piston (18) from the stator (40).

Abstract: A caliper brake (10) is adapted to act upon a stator (40) to engage a rotor of a vehicle. A housing (11) carries both a spring applied hydraulically released piston assembly (12) and a pressure intensifying piston assembly (14). The assemblies (12, 14) are in fluid communication with each other. The assembly (12) includes a piston (18) and a spring assembly (20) which urges the piston (18) into a first position engaging the stator (40). The piston assembly (14) includes a pressure intensifying (PI) piston (64) which is in a first position when the piston (18) is in the first position. When the PI piston (64) moves from a first position to a second position, the fluid acts upon the piston (18) thereby disengaging the piston (18) from the stator (40).

Abstract: A parking brake system includes an engine oil pressure switch normally controlling the activation of a parking brake. The controller is actuated to temporally ignore a communication from the engine oil pressure switch so that the brake may be released even when the engine is disabled.

Abstract: A hydraulic pressure multiplier having a housing, a bore in the housing and an outer piston slidably positioned within the bore. The pressure multiplier also includes an inner piston having a bore therethrough, the inner piston being positioned within a bore within the outer piston. An opening is provided through an end wall of the outer piston, and a mechanism is provided to selectively control hydraulic fluid flow into the bore within the outer piston. Hydraulic fluid first flows through the opening in the outer piston and through the bore through the inner piston to actuate a slave cylinder or a hydraulic piston within a brake. After a threshold pressure is reached within the slave cylinder, the valve closes and the outer piston is caused to move axially, thereby providing an increased hydraulic pressure within the slave cylinder.

Abstract: A two-stage slave cylinder including a housing and a bore extending within the housing. An outer piston is slidably positioned within the bore in the housing, and an outer piston chamber is defined by the bore and the outer piston. The outer piston chamber is connected to a hydraulic fluid source by a fluid passageway. A biasing mechanism acts to bias the outer piston in an unactuated position unless a force is exerted on the outer piston that is greater than the biasing force. A bore is provided in the outer piston, and an inner piston is slidably positioned therein. An inner piston chamber is defined by the bore and the inner piston, and an opening is provided in the outer piston to connect the outer piston chamber to the inner piston chamber. A valve assembly is provided within the opening in the outer piston to control the flow of fluid between the outer piston chamber and the inner piston chamber.

Abstract: A hydraulic pressure multiplier having a housing, a bore in the housing and an outer piston slidably positioned within the bore. The pressure multiplier also includes an inner piston having a bore therethrough, the inner piston being positioned within a bore within the outer piston. An opening is provided through an end wall of the outer piston, and a mechanism is provided to selectively control hydraulic fluid flow into the bore within the outer piston. Hydraulic fluid first flows through the opening in the outer piston and through the bore through the inner piston to actuate a slave cylinder or a hydraulic piston within a brake. After a threshold pressure is reached within the slave cylinder, the valve closes and the outer piston is caused to move axially, thereby providing an increased hydraulic pressure within the slave cylinder.

Abstract: A caliper brake including a housing, an opening in the housing, and an actuating assembly received in the opening. The actuating assembly includes an actuating lever having a cam surface and a pivot aperture, a cable bracket having a cable retaining flange, a pivot aperture, and a retaining portion, and a pin received through said pivot apertures to rotatably secure the actuating lever to the cable bracket. The retaining portion of the cable bracket acts to secure the actuating assembly in the opening of the housing without the need for mechanical fasteners. A pivot plate may also be provided, the pivot plate having a pivot aperture and a retaining portion, and is positioned on one side of the actuation lever opposite the cable bracket. A cable housing is received in a bore through the cable retaining flange, and an actuation cable is slidably positioned therein and secured at one end to the actuation lever.

Abstract: A two-stage slave cylinder including a housing and a bore extending within the housing. An outer piston is slidably positioned within the bore in the housing, and an outer piston chamber is defined by the bore and the outer piston. The outer piston chamber is connected to a hydraulic fluid source by a fluid passageway. A biasing mechanism acts to bias the outer piston in an unactuated position unless a force is exerted on the outer piston that is greater than the biasing force. A bore is provided in the outer piston, and an inner piston is slidably positioned therein. An inner piston chamber is defined by the bore and the inner piston, and an opening is provided in the outer piston to connect the outer piston chamber to the inner piston chamber. A valve assembly is provided within the opening in the outer piston to control the flow of fluid between the outer piston chamber and the inner piston chamber.