A method of maintaining a backpressure of a fluidic product is provided. The method includes pressurizing a first reservoir to a first predetermined pressure level using compressed air, delivering the fluidic product to the pressurized first reservoir until a current level of the fluidic product in the first reservoir reaches a first predetermined level, pressurizing a second reservoir to a second predetermined pressure level using the compressed air, delivering the fluidic product to the pressurized second reservoir until a current level of the fluidic product in the second reservoir reaches a second predetermined level, and controlling the backpressure of the fluidic product using the first reservoir and the second reservoir such that a discharge flow of the fluidic product is continuous.

A vehicle air suspension installation includes pneumatics configured for operation in conjunction with a compressed air supply installation, and comprises: a pneumatic line having a port connection to the air supply installation, air bellows, each serving as a pressure chamber for an air spring, one air bellows being connected to the pneumatic line via a directional solenoid valve, and the air bellows being fillable/bleedable depending on a switching state of the valve, and first and second directional valves forming a solenoid valve system, which has a pneumatic part that is actuatable by a magnetic part. The first directional valve forms a primary valve, and the second forms a secondary valve. First and second air bellows associated with the valve system are fillable/bleedable depending on the switching state of the primary and secondary valves. The primary and secondary valves are controllable by a controller of the magnetic part. The controller is common to and acts upon both valves.

A dryer circuit for a pneumatic regulating device of a vehicle, comprising an air dryer, and a first compressor, wherein the first compressor is designed to compress system air present in the pneumatic regulating device, wherein the air dryer, the first compressor and subsystems, which can be connected to the first compressor, of the pneumatic regulating device are arranged in such a way that, in the operating mode of a closed air supply, air delivered between the components of one of the subsystems by the first compressor is delivered so as to bypass the air dryer.

A vehicle-height control system includes: a fluid supply and discharge device including a compressor configured to suck fluid, and a tank configured to supply the fluid; an actuator-side passage connected to the fluid supply and discharge device; a vehicle-height control actuator provided for a wheel and connected to the actuator-side passage via a vehicle-height control valve; and a vehicle height controller configured to control a vehicle height for the wheel by controlling the fluid supply and discharge device and the vehicle-height control valve to control supply and discharge of the fluid in the vehicle-height control actuator. The vehicle height controller includes a start controller configured to open the vehicle-height control valve after establishing communication between the actuator-side passage and at least one of the tank and the compressor in a state in which the vehicle-height control valve is closed at a start of control of the vehicle height.

A compressed air supply unit for operating a pneumatic unit by means of a compressed air flow, in particular of an air suspension unit of a vehicle, comprises an air dryer arrangement in a main pneumatic line that pneumatically links a compressed air feed line from an air compressor and a compressed air connection to the pneumatic unit. A valve arrangement is pneumatically connected to the main pneumatic line for controlling the compressed air flow. The air dryer arrangement has a drying container having a container outer wall. A partition along a length of the drying container divides an internal space delimited by the container outer wall into first and second chambers delimited by the partition and the container outer wall. The partition adjoins the container outer wall along the length of the drying container, and the first and second chambers are adjacent to one another along that length.

A vehicle-height control system includes: a vehicle-height control actuator; a pressure-medium supply and discharge device configured to supply and discharge a pressure medium; and a vehicle height controller configured to control a vehicle height by controlling the pressure-medium supply and discharge device. The pressure-medium supply and discharge device includes a compressor and a tank configured to contain a pressure medium supplied from the compressor. The vehicle height controller includes a down controller configured to operate the compressor to discharge and supply the pressure medium from the vehicle-height control actuator to the tank to lower the vehicle height when a tank pressure is less than a set pressure. The down controller is configured to discharge the pressure medium from the vehicle-height control actuator to an outside to lower the vehicle height when the tank pressure is greater than or equal to the set pressure.

A vehicle-height adjustment system includes: a vehicle-height adjustment actuator provided so as to correspond to a wheel; and a pressure-medium supply and discharge device configured to supply and discharge a pressure medium to and from the vehicle-height adjustment actuator. The pressure-medium supply and discharge device includes a tank configured to store the pressure medium. The vehicle-height adjustment system includes a tank-pressure controller configured to control a tank pressure based on at least one of a vehicle height for the wheel and an inside temperature. The tank pressure is a pressure of the pressure medium stored in the tank, and the inside temperature is a temperature in the vehicle-height adjustment system.

A vehicle-height control system is configured to control a vehicle height for a wheel. The vehicle-height control system includes: a vehicle-height control actuator provided so as to correspond to the wheel; a pressure-medium supply and discharge device configured to supply and discharge a pressure medium to and from the vehicle-height control actuator; and a vehicle height controller configured to control the vehicle height for the wheel by controlling the pressure-medium supply and discharge device based on an inside temperature and an outside-air temperature to control at least one of supply and discharge of the pressure medium to and from the vehicle-height control actuator. The inside temperature is a temperature in the vehicle-height control system.

A system and apparatus that reduces tire scrub on a truck and or trailer during turns. The system minimizes the redistribution of the load among the tires thereby spreading the load of the trailer or truck among the tires avoiding unnecessary overloading. The system operates without operator intervention and is capable of operating automatically on trailers, without control signals from the truck.

A method for operating a pressure control system having a multistage compressor. The method comprises providing a pressure medium compressed multiple times by the multistage compressor in order to fill a pressure medium reservoir or pressure medium chambers of the pressure control system, by performing (i) providing, by a first compression stage, a precompressed pressure medium and additionally compressing the precompressed pressure medium via a second compression stage, and/or (ii) introducing, into an intermediate volume between the first compression stage and the second compression stage of the multistage compressor, an already compressed charge pressure medium and compressing, by the second compression stage, the charge pressure medium again. An intermediate pressure of the precompressed pressure medium conveyed into the intermediate volume is limited by an overpressure valve interacting with the first compression stage. The overpressure valve is configured to open if the intermediate pressure exceeds a limit value.