An air suspension apparatus includes a compressor configured to compress air, a tank configured to store the air, a tank-side suction conduit configured to supply the compressed air in this tank to an intake side of the compressor, a tank conduit connecting a discharge side of the compressor and the tank, an air suspension connected to the discharge side of the compressor via an air drier, an intake electromagnetic valve provided in the tank-side suction conduit, a return electromagnetic valve provided in the tank conduit, and a discharge conduit provided so as to branch off from between the discharge side of the compressor and the air drier and configured to be connected to an atmosphere by opening a discharge electromagnetic valve.

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 vehicle height adjustment apparatus includes: vehicle height adjustment units respectively provided to correspond to wheels of a vehicle body, and adjusting a vehicle height in response to the supply and discharge of a working fluid; a pressure tank storing the working fluid; a compressor pressure-feeding the working fluid; a valve body block formed by opening and closing valves, and interposed between the pressure tank and the compressor, and the vehicle height adjustment units; and a control unit adjusting a vehicle height by controlling the valve body block, wherein the valve body block is connected to the pressure tank, and working fluid outlet and inlet of the compressor, and upon the completion of the pressure feed of the working fluid, the control unit controls such that the working fluid outlet and inlet are communicated with each other.

A controlled air spring system with a compressed air supply for height regulation of a vehicle includes a number of air springs and a reservoir for the storage of compressed air, a number of switching valves for height regulation, and a controller configured to actuate the number of switching valves. The at least one switching valve is actuated with a number of sequential switching periods and switches over in a switching period, between a first switching state with an open valve state and a second switching state with a closed valve state, the switching period of the number of sequential shifting periods having the open valve state and the closed valve state. The controller is configured to set a speed for a height change of the height regulation. The setting of the speed takes place via an open/closed parameter.

An air suspension system includes: an air suspension interposed between a vehicle body and an axle to adjust a vehicle height according to supply and exhaust of air; a compressor that compresses air; a tank that stores the air compressed by the compressor; and an air dryer provided on an ejection side of the compressor. When the tank has a predetermined pressure or less after air is supplied from the tank to the air suspension, a pressure of the tank is increased by the compressor.

A pneumatic automotive height adjuster assembly provides at least one bag removably connected to a vehicle having a frame. The at least one bag is configured to adjust a height of the frame. An air supply line has a supply end and a discharge end. The discharge end is in fluid communication with each of the at least one bag. The air supply is configured to provide air to inflate the at least one bag. A switch is in fluid communication with the supply end of the air supply line. The switch has a first discharge, a second discharge, and a switch input. A leveling valve is in fluid communication with the first discharge. The air supply line is in fluid communication with the second discharge. An air supply is in fluid communication with the leveling valve and the switch input.

An air suspension apparatus includes a compressor configured to compress air, a tank configured to store the air, a tank-side suction conduit configured to supply the compressed air in this tank to an intake side of the compressor, a tank conduit connecting a discharge side of the compressor and the tank, an air suspension connected to the discharge side of the compressor via an air drier, an intake electromagnetic valve provided in the tank-side suction conduit, a return electromagnetic valve provided in the tank conduit, and a discharge conduit provided so as to branch off from between the discharge side of the compressor and the air drier and configured to be connected to an atmosphere by opening a discharge electromagnetic valve.

A suspension control valve arrangement for a pneumatic suspension system of a commercial vehicle includes a supply port, a delivery port, an exhaust port, a service valve arrangement, and an operation control mechanism (5, 6) for switching the service valve arrangement into one of the following normal operation modes of a normal operation status: a blocking position for a blocking mode for blocking an air supply from the supply port to the delivery port, a supply position for a supply mode for supplying air from the supply port to the delivery port, or an exhaust position for a normal exhaust mode for connecting the delivery port to the exhaust port. A dump-control device (7, 11) in the housing (2) is configured for switching between the normal operation status and a quick-dump mode (IV), win which the delivery port is connected to the exhaust port by bypassing the service valve arrangement.