Wabco Gmbh

Zf Cv Systems Hannover Gmbh

Joachim Reinhardt

Heinrich Diekmeyer

Bernd Strilka

Frank-Dietmar Lippelt

Wolfgang Strache

Stefan Brinkmann

Carsten Detlefs

Christoph Wilken

Kevin Pendzich

Andreas Schäl

A control device for a compressed air preparation device of a vehicle outputs output signals for adjusting feed phases and regeneration phases of the compressed air preparation device. A compressor feeds compressed air via an air dryer having a desiccant into a compressed air reservoir in a feed phase, and compressed air is passed out of the compressed air reservoir through the air dryer for drying the desiccant in a regeneration phase. The control device adjusts the regeneration phases depending on a current or future engine load and/or a current or future consumption of compressed air by the vehicle. In overrun phases, the desiccant can be excessively dried to a low moisture level in order to save fuel in later travel segments. Route-optimized regeneration of the desiccant as a function of engine load and/or utilization phases can also be effected.

Control device and control method for a vehicle compressed air preparation device

An electronic compressed air system for vehicles includes a compressed air supply part having a compressor, a compressed air consumer part having load circuits forming an air-suspension circuit, and service-brake circuits having reservoirs. The load circuits are supplied with compressed air via solenoid valves. The pressure in the load circuits is monitored by pressure sensors whose signals are evaluated by an ECU that controls the solenoid valves. The solenoid valve of the air-suspension circuit does not include reservoirs and is closed in the de-energized normal state. The solenoid valves of other load circuits, especially of the service-brake circuits are open in the de-energized normal state. With a pressure demand of the air-suspension circuit, the associated solenoid valve is switched by the ECU to open position to establish communication with the compressed air supply part and/or with the service-brake circuits or with the reservoirs thereof, to refill the air-suspension circuit.

Electronic compressed air system

A vehicle compressed air supply system includes a supply part with compressor, an air drying part and a consumer part including consumer circuits with brake circuits supplied with compressed air via a multi-circuit safety valve. The brake circuits, and optionally at least one other consumer circuit, include compressed air tanks. Pressure in the circuits is monitored by sensors and evaluated by an electronic control device. To determine system parameters in terms of tank size and compressor output, when filling circuits, the rate of pressure increase in a circuit is determined as a function of compressor speed, and air-drying regeneration is effected. The period of a pre-defined pressure drop or pre-defined pressure gradient is determined and air volume for completing regeneration is calculated from the magnitude of the pressure drop, regeneration time and throttle diameter. Tank volume is determined therefrom. Compressor output is calculated from tank volume and rate of pressure increase.

Compressed air supply system and method for determining system parameters

To detect a defect or failure of a compressed air load circuit in a compressed air system for vehicles, pressure is measured in compressed air load circuits and evaluated in an electronic control unit, which briefly shuts off the compressed air load circuits, measures pressure values and/or determines pressure gradients during the shutoff time and compares the pressure values and/or the determined pressure gradients with a respective threshold value, identifies defective circuits and definitively shuts off circuits detected as defective if the results are below the threshold value.

Method and system for identifying a defect or failure of a compressed air load circuit in an electronic compressed air installation for vehicles

To detect a failure of a compressed air consumer circuit in a compressed air system for vehicles, pressure is continuously measured in compressed air consumer circuits and evaluated in an electronic control unit which compares the pressure values and/or determined negative pressure gradients of the compressed air consumer circuits with a respective threshold value and shuts off an air-consumer circuit if the pressure values and/or negative pressure gradients thereof satisfy a circuit-failure criterion. The circuit-failure criterion is satisfied when the pressure values and/or pressure gradients are below the respective threshold value for a time equal to or longer than the time of a dynamic pressure change or of a dynamic pressure collapse.

Method and system for identifying a malfunctioning compressed air consumer circuit in a vehicle electronic compressed air system

A method and system is provided for refilling vehicle operational brake circuits after a large consumption of compressed air. The operational brake circuits are compressed air consumer circuits of a consumer part of a vehicle compressed air system. The operational brake circuits also include at least one additional compressed air consumer circuit provided with a compressed air reservoir. The actual pressure values in the operational brake circuits and in the additional compressed air consumer circuit are continuously determined and compared against a lower threshold value. If the values are below the threshold value, the identified operational brake circuits are blocked as defective and communication is established between the additional compressed air consumer circuits and the intact operational brake circuits in order to refill the operational brake circuits from the compressed air reservoirs of the additional compressed air consumer circuits.

Growing community of inventors

Hannover, Germany

Joachim Reinhardt