A vehicle air management system is provided. The vehicle air management system comprises an air tank and a boost air tank. Based on a signal indicative of an air consumption level of at least one air consumer, a control unit is configured to control the vehicle air management system to deliver pressurized air from the boost air tank to be supplied to an air compressor.

An electric height control device may include: an oil storage part configured to store oil therein; a motor driving part inserted into the oil storage part and driven when power is applied thereto; a hydraulic block part coupled to the motor driving part, connected to the oil storage part, and configured to amplify oil; and a control part coupled to the hydraulic block part, and configured to control the motor driving part and the hydraulic block part.

A sensor arrangement for an air suspension system of a vehicle has a change-over valve for each air spring of a vehicle axle or of multiple, adjacent tandem axles, and has a shutoff valve for the air spring of each vehicle wheel of the axle or for each of the air springs on each side of the tandem axles. The respective changeover valve and the shutoff valves are structurally combined in a valve block arranged at a distance from the air springs. For measuring the pressure in each of the bellows of the air springs, pressure sensors are arranged in or on the valve block. Each of the pressure sensors is connected at the output of the shutoff valve associated with the sensor to the connection line of the bellows of the associated air spring or of the bellows of the associated air springs.

A method for controlling an air suspension system of a vehicle includes: a) determining a bellows pressure-time characteristic curve for air admission to and release from the bellows of one air spring or the bellows of a plurality of air springs, the characteristic curve being normalized with the value of a supply pressure in a reservoir for compressed air, b) sensor measurement of a current pressure in the spring bellows of the air springs as well as the current supply pressure immediately before air admission thereto or air release therefrom, c) determining, from the normalized characteristic curve, the opening duration for the associated shutoff valve using the ratio of the measured bellows pressure to the measured supply pressure and the ratio of the provided target pressure to the measured supply pressure, d) opening the associated shutoff valve for the determined opening duration in order to set the provided target pressure.

A hydraulic level-adjustment device has a reservoir, a reversible hydraulic unit with a hydraulic pump, and a single-acting hydraulic linear actuator. To lift a vehicle chassis, the working space of the linear actuator can be pressurized by the hydraulic pump operated in its first pumping direction via its first pump connection and a fill line with a fill-check valve arranged therein. To lower the chassis, via its second pump connection, the hydraulic pump, operated in the reverse pumping direction, pumps hydraulic fluid into the reservoir via an outflow line with a throttle unit arranged therein. The pressure present upstream of the throttle unit acts on the control connection of a lockable, drainage-check valve via a control line and opens same, so that, under the weight of the motor vehicle, hydraulic fluid is forced out of the working space of the hydraulic linear actuator into the reservoir via the drainage line.

An air management system for a vehicle. The air management system includes at least one air spring. A compressor is provided for filling the air spring. A central air line is fluidly connected to the air spring and the compressor. At least one spring air line extends between the central air line and the air spring. At least one suspension valve is disposed along the spring air line. At least one auxiliary air line extends between the spring air line and the central air line. At least one high flow exhaust valve is disposed along the auxiliary air line. At least one isolation check valve is disposed in series with the high flow exhaust along the spring air line. The isolation check valve allows air to pass through therethrough from the air spring to the central air line while preventing air from passing therethrough from the central air line to the air spring.

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 supply system block including one or more air spring valves, where the one or more air spring valves are disposed within the air supply system block, the air supply system block having a valve block housing. The system further includes the air supply system block pneumatically coupled with one or more air springs, and at least one reservoir coupled with the air supply system block, at least one motor and pump disposed within the air supply system block. The air suspension further includes fast down leveling valves disposed within the air supply system block.

An example valve assembly includes a mounting plate having an inlet port configured to be fluidly coupled to a source of fluid; a pilot supply valve mounted to the mounting plate, wherein the pilot supply valve comprises (i) an inlet port fluidly coupled to the inlet port of the mounting plate, and (ii) a first outlet port configured to be fluidly coupled to a pilot port of a main valve; and a pilot exhaust valve mounted to the mounting plate, wherein the pilot exhaust valve comprises (i) a vent port, (ii) a second outlet port that is fluidly coupled to the first outlet port of the pilot supply valve.

Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.