A compressed-air feed system for operating a pneumatic system includes a compressed-air supply, a compressed-air connection to the pneumatic system, at least one ventilation connection to surroundings, and a pneumatic main line between the compressed-air supply and the compressed-air connection. The pneumatic main line has an air dryer and a regeneration throttle. The compressed-air feed system further includes a first ventilation line between the pneumatic main line and the at least one ventilation connection. The first ventilation line has a first ventilation valve and a ventilation throttle. The compressed-air feed system additionally includes a second ventilation line between the compressed-air connection and the at least one ventilation connection. The second ventilation line has a second ventilation valve formed as a 2/2 directional valve. The compressed-air feed system is designed to provide an operating mode in which the second ventilation valve is open over a predetermined time period.

An air suspension system includes air suspensions (1, 2) performing vehicle height adjustment in response to supply and discharge of air, a compressor (3) compressing air, a tank (4) storing compressed air, a first passage (6) connecting between the delivery side of the compressor and the tank, and a second passage (7) connecting between the delivery side of the compressor and the air suspensions. A first dryer (10) is provided in the middle of the first passage to dry air flowing through the first passage. A second dryer (11) is provided in the middle of the second passage to dry air flowing through the second passage. Thus, compressed air generated from ambient air sucked in by the compressor can be dried by the second dryer and supplied directly into the air chambers of the air suspensions.

A method for operating a pneumatic system having a compressed air supply system and an air spring system includes determining at least one deflection of at least one air spring of the pneumatic system. The air spring is configured to be connected to a gallery in a selectively gas-conveying manner via a valve. The method further includes determining at least one bellows volume of a spring bellows of the at least one air spring based on the at least one determined deflection, indicating a pneumatic surrogate model for the at least one bellows volume and/or for a pressure accumulator volume of a pressure accumulator of the pneumatic system based on a mass flow balance for a balance volume, and calculating, based on the pneumatic surrogate model, at least one pressure value of the at least one bellows volume, the pressure accumulator volume, and/or the balance volume.

An air suspension system includes a tank, a tank-side open/close valve, an air suspension-side open/close valve, a system portion, and the like. The system portion includes a compressor, an air drier, and a first passage and a second passage provided between the tank-side open/close valve and the air suspension-side open/close valve in parallel, a discharge valve, a tank-side control valve, an air suspension-side control valve, and the like. Due to this configuration, the air suspension system regenerates the air drier by opening the discharge valve to thus cause the air in the second passage to flow from an opposite side toward one side of the air drier when no power is supplied to the tank-side control valve and the air suspension-side control valve.

A housing includes an air introduction flow passage, an air discharge flow passage, and a desiccant agent accommodated in the housing. One end portion of the housing is at a lower side of the housing in a vertical direction aligned with the axial direction. An air-liquid separation chamber is formed at a bottom portion of the housing, and includes an air supply passage supplying air to the desiccant agent at an upper housing surface, and is communicated with the air introduction flow passage and the air discharge flow passage to separate moisture in the air introduced from the air introduction flow passage. An adsorption member is accommodated in the air-liquid separation chamber to adsorb moisture separated in the air-liquid separation chamber. Air introduced from the air introduction flow passage is supplied to an air suspension device through the adsorption member and the desiccant agent.

An air management system and method are provided. The system includes a pressurized air source. A manifold block is coupled to the pressurized air source and includes a plurality of suspension valves in fluid communication with the pressurized air source for controlling air flow to and from a plurality of air springs. An accumulator is coupled to the manifold block for storing air. An accumulator valve is in fluid communication with the plurality of suspension valves and the accumulator to allow exhausted air from the plurality of air springs into the accumulator. An electronic control unit is electrically coupled to the plurality of suspension valves and the accumulator valve for controlling a sequence of operating the accumulator valve and the plurality of suspension valves to provide enhanced exhaust flow from the plurality of air springs to maintain the vehicle in a level orientation while lowering the vehicle.

A reciprocating-piston machine includes at least one first cylinder and at least one first piston assigned to the first cylinder as well as at least one second cylinder and at least one second piston assigned to the second cylinder. During operation, the first piston and the second piston are deflected in a respective cylinder displacement chamber of the respective first cylinder and the second cylinder. The reciprocating-piston machine further includes a crankshaft which, during operation, can be driven and which has an eccentric crankshaft journal and a drive shaft coupling designed for the coupling of a drive shaft of a drive motor for driving the crankshaft. Additionally, the reciprocating-piston machine includes a first connecting rod configured to deflect the first piston, a second connecting rod configured to deflect the second piston, and a bearing pin about which the first and second connecting rod are rotationally movable.

The objective is to improve the oil trapping rate of an oil separator. The oil separator separates gas and liquid in air containing oil, recovers liquid that contains oil. The oil separator is provided with an introduction port for introducing air, an oil trap for trapping oil contained in air, a reservoir for storing the liquid flowing out of the oil trap, and a discharge port for discharging air from which oil has been removed. The oil trap includes a glass fiber filter and an impingement member, which traps oil particles by causing the oil particles to strike the impingement member.

A method for actuating a solenoid valve, which is loaded with a pneumatic pressure medium, in order to reduce a pressure (p.sub.sys) which is applied to the solenoid valve, where the solenoid valve assumes a closed switching position in the deenergized state and assumes a completely open switching position when it is energized with a switching current intensity (I.sub.s(p)) which is dependent on the applied pressure (p.sub.sys), where a first rise current final value (I.sub.1) is predetermined, which first rise current final value is smaller than the switching current intensity (I.sub.s(p)), where the solenoid valve is energized with an actuating current which follows an actuating current profile (SV1, SV2), and where the actuating current profile (SV1, SV2) comprises a first rise phase (TA1), in which the actuating current is increased to the predetermined first rise current final value (I.sub.1), and, following said first rise phase, a first holding phase (TH1) in which the actuating current is held constant at the first rise current final value (I.sub.1).

A method for the treatment of air of a compressed air system for a motor vehicle, the compressed air system comprising an air compressor, an air dryer and an ambient temperature sensor, wherein an exchange operation of a system air volume is performed by the air compressor, wherein during the exchange operation a part of the system air from the compressed air system is released into the surroundings and ambient air is filled into the compressed air system. The method includes determining a current ambient temperature value (T.sub.U) using the ambient temperature sensor, checking a first condition, whether or not the current ambient temperature value (T.sub.U) is lower than a temperature limit value (T.sub.G), and performing the exchange operation to lower the dew point of the system air by the air dryer if the first condition is satisfied.