A compressed air drying device that dries compressed air discharged from a compressor includes a dryer and a controller. The dryer includes a drying container, which is filled with a desiccant, and a discharge valve arranged in a discharge port that discharges drainage produced by regeneration of the desiccant. The controller obtains an ambient temperature and controls opening and closing of the discharge valve. When the ambient temperature is a temperature at which freezing occurs, the controller moves the compressed air, which is discharged from the compressor and heated, into the dryer and restricts opening of the discharge valve.

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.

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.

The invention relates to an integrated air-supply unit, in particular for air-suspension systems for motor vehicles, said unit comprising an air compressor having an electric motor and an air dryer. The air compressor together with the electric motor, air dryer and a number of pneumatic connections form a functional unit.

A compressed-air drying system includes an air dryer, an oil mist separator and a reservoir. The air dryer includes desiccant and a drain port for draining liquid generated through regeneration of the desiccant. The oil mist separator includes a trapping portion for trapping oil contained, as oil mist, in the compressed air. The oil mist separator further includes a drain port for draining liquid containing the trapped oil. The oil mist separator is provided in a passage between the compressor and the air dryer. The reservoir stores the liquid drained from the air dryer and the liquid drained from the oil mist separator. The drain port of the air dryer and the drain port of the oil mist separator are connected to the reservoir.

A concurrent leveling system includes a pressurized air source. A manifold block, having a body defining an air feed inlet, is disposed between air springs and the pressurized air source. The body includes front and rear suspension valves. Each of the suspension valves defines a suspension valve orifice having a first predetermined diameter. The body includes at least one restrictor valve parallel to and in fluid communication with the front suspension valves. The at least one restrictor valve includes a first check valve and a first blocker valve orifice defining a first orifice diameter. The first check valve and the first blocker valve orifice are disposed parallel to one another and in series with the front suspension valves and in fluid communication with the air feed inlet and the front suspension valves for reducing fluid back flow to allow the vehicle to be lowered in nominal loading conditions.

An air suspension system capable of raising both the vehicle front wheel side and the vehicle rear wheel side by using a single tank. The air suspension system (1) includes a front wheel-side air suspension (2) and a rear wheel-side air suspension (7) which are interposed between a vehicle body and associated axles to perform vehicle height adjustment in response to supply and discharge of air, a compressor (17) for compressing air, and a tank (27) for storing air compressed by the compressor. When the vehicle height is to be raised by the air suspensions, the front wheel-side air suspension is supplied with compressed air from the tank, and the rear wheel-side air suspension is supplied with compressed air from the tank after the compressed air has been pressurized by the compressor.

Provided is a closed type air suspension apparatus requiring no complicated control and capable of simplifying the overall structure. The air suspension apparatus includes a tank storing air, a return valve returning compressed air in an air suspension to the tank, a discharge valve discharging compressed air in the tank to the outside through an intake-discharge port when the compressed air between the intake side of a compressor body and the tank reaches a first value or more, and an intake valve opening when the pressure of the air between the intake side of the compressor body and the tank is at a second value less than the first value, thereby allowing the atmosphere (air) to be taken in from the intake-discharge port. The compressor body of a compressor compresses air including the compressed air in the tank.

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.

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.