Lubricating performance of a parking brake is ensured and fuel efficiency during traveling is improved. A parking brake for braking rotation of an output shaft is disposed around the output shaft rotated by driving force. The output shaft is provided with an axial oil passage, a first discharge hole, and a second discharge hole. The axial oil passage extends in an axial direction of the output shaft. The first discharge hole and the second discharge hole communicate with the axial oil passage and open in an outer circumferential surface of the output shaft at an installation position of the parking brake in the axial direction.

The present invention relates to an electronic parking brake device for a vehicle, in particular a utility vehicle. As a function of at least one operating state of a towing vehicle parking brake supply line and/or a trailer parking brake supply line, a towing vehicle parking brake control valve is activatable by means of a control unit in such a way that a towing vehicle parking brake supply line can be deaerated or aerated by the towing vehicle parking brake control valve. By manually actuating a trailer parking brake control element, a trailer parking brake control valve is activatable by means of the control unit in such a way that a trailer parking brake supply line can be deaerated or aerated by the trailer parking brake control valve. The present invention also relates to a method for operating the above electronic parking brake device for a vehicle.

A single chain drive is disclosed that includes a drive sprocket, a drive motor, idler sprockets, front and rear axle sprockets, and a single chain. The drive motor rotates the drive sprocket, which rotates the idler sprockets, which rotate the single chain, which rotates the front and rear axle sprockets. The drive sprocket can be a lantern gear with covers, and pins that connect the cover, and the idler sprockets can have teeth that mesh with the pins between the covers of the drive sprocket. A drive shaft can couple the drive motor and drive sprocket, and an integrated parking brake can prevent rotation of the drive shaft when engaged. A chain case with lubricant can enclose the drive sprocket, idler sprockets, chain, and axle sprockets. The drive sprocket, idler sprockets and axle sprockets can be sized to provide a desired gear reduction.

A brake system for a vehicle, the vehicle including a service brake control module and a parking brake with at least one spring brake chamber, the service brake control module controlling at least a first pressure module to brake a first set of wheels. The brake system comprises a parking brake control module configured to control the spring brake chamber to brake a second set of wheels and to control the first pressure module to brake the first set of wheels.

A work vehicle provided with a loading hydraulic circuit (A), including at least a main hydraulic pump (31), a lift arm cylinder (8) and a control valve (32), an auxiliary hydraulic pump (31), a negative parking brake device (PB), and a parking brake releasing hydraulic circuit (B2), in which the vehicle includes: a loading operation hydraulic circuit (B1) located upstream of the parking brake releasing hydraulic circuit; an emergency flow path (80) for supplying the pressure oil discharged from the auxiliary hydraulic pump to the parking brake device through the loading operation hydraulic circuit in an emergency; and a valve unit (81) located in the emergency flow path. If the pressure of the parking brake releasing hydraulic circuit is lower than the brake release pressure to release the braking state of the parking brake device, the valve unit is switched to the communicating position.

A system for controlling compounding in a vehicle brake actuator includes first and second valves configured to control, respectively, a first fluid pressure in a parking brake chamber of a brake actuator that acts against a spring force applied by a spring of the actuator to a pushrod of the actuator and a second fluid pressure in a service brake chamber of the actuator that applies a fluid force to the pushrod. A controller is configured to receive first and second fluid pressure signals indicative of the first and second fluid pressures, determine a total brake actuator force applied to the pushrod responsive to the first and second fluid pressure signals and control at least one of the first and second valves responsive to the total brake actuator force to adjust a corresponding one of the first and second fluid pressures and thereby obtain an adjusted total brake actuator force.

A system for controlling compounding in a vehicle brake actuator includes first and second valves configured to control, respectively, a first fluid pressure in a parking brake chamber of a brake actuator that acts against a spring force applied by a spring of the actuator to a pushrod of the actuator and a second fluid pressure in a service brake chamber of the actuator that applies a fluid force to the pushrod. A controller is configured to receive first and second fluid pressure signals indicative of the first and second fluid pressures, determine a total brake actuator force applied to the pushrod responsive to the first and second fluid pressure signals and control at least one of the first and second valves responsive to the total brake actuator force to adjust a corresponding one of the first and second fluid pressures and thereby obtain an adjusted total brake actuator force.

A work machine can include a frame; a plurality of transportation devices attached to the frame; an engine to provide a propel pressure to the plurality of transportation devices; a brake pack associated with one or more of the plurality of transportation devices; and a controller configured to perform a brake pack test by receiving the propel pressure and a machine speed and wherein the controller determines a brake pack life remaining based on the propel pressure of the machine when the machine speed rises above zero.

A single chain drive is disclosed that includes a drive sprocket, a drive motor, idler sprockets, front and rear axle sprockets, and a single chain. The drive motor rotates the drive sprocket, which rotates the idler sprockets, which rotate the single chain, which rotates the front and rear axle sprockets. The drive sprocket can be a lantern gear with covers, and pins that connect the cover, and the idler sprockets can have teeth that mesh with the pins between the covers of the drive sprocket. A drive shaft can couple the drive motor and drive sprocket, and an integrated parking brake can prevent rotation of the drive shaft when engaged. A chain case with lubricant can enclose the drive sprocket, idler sprockets, chain, and axle sprockets. The drive sprocket, idler sprockets and axle sprockets can be sized to provide a desired gear reduction.

A work vehicle includes a drive axle assembly having an axle housing with an input opening and output openings in communication with an interior cavity. A gear assembly is disposed in the interior cavity of the axle housing, with the gear assembly having an input shaft extending through the input opening and coupled for co-rotation with a drive shaft. A park brake assembly is integrated with the drive axle assembly and is disposed within the axle housing. The park brake assembly imparts a brake force to arrest rotation of the input shaft, with the park brake assembly including a brake pack and a piston disposed about the input opening of the axle housing and with the piston configured to move relative to and act on the brake pack. A Belleville spring arrangement is also disposed about the input opening of the axle housing and acts on the piston to engage or release the park brake.