Electrical parking brake system for a utility vehicle and operating method

摘要

An electrical parking brake system and method for a commercial vehicle includes a valve device, which connects a compressed-air supply with a spring brake cylinder without an intermediate connection of a hand brake valve. The valve device aerates the spring brake cylinder in a first switching state and deaerates the spring brake cylinder in a second switching state. The system further includes a pressure sensor, which measures a pressure on the compressed air supply side, and an electronic control unit for directly or indirectly controlling the valve device, acquiring a signal supplied by the pressure sensor, and acquiring an indicator signal for the presence of an individual in a cab of the vehicle. The valve device can only be transferred to its first switching state by the control unit if the pressure on the compressed air supply side exceeds a pressure threshold value and if the presence of an individual in a cab of the vehicle is indicated.

主权项

1. An electrical parking brake system for a commercial vehicle, comprising:
a spring brake cylinder; a valve device operatively configured to connect a compressed-air supply to a parking brake supply line of the spring brake cylinder without an intermediate hand brake valve between the compressed-air supply and the valve device, the valve device aerates the spring brake cylinder in a first switched state to release the parking brake and deaerates the spring brake cylinder in a second switched state to engage the parking brake; a pressure sensor operatively configured to sense a compressed-air-supply-side pressure in the first switched state and in the second switched state; a vehicle occupancy sensor operatively configured to sense a presence of a person in a driver's cab of the commercial vehicle; an electronic control unit operatively configured for actuating the valve device, registering a signal supplied by the pressure sensor, and registering an indicator signal for the presence of a person in the driver's cab of the commercial vehicle; wherein the valve device is actuatable by the electronic control unit independent from a pressure level in the spring brake cylinder by the electronic control unit to deaerate the spring brake cylinder; and wherein the electronic control unit is configured to transfer the valve device into the first switched state only when the compressed-air-supply-side pressure exceeds a defined pressure threshold value and the indicator signal indicates that the person is present in the driver's cab of the commercial vehicle.