Abstract: A residual pressure holding valve (1) for a hydropneumatic suspension strut (2) of a motor vehicle has a valve housing (3) with an air inlet (4) and an air outlet (5). A valve body (6) is arranged displaceably in the valve housing (3) and a valve element (7) is arranged displaceably in the valve body (6). Air pressure applied to the air inlet (4) can lift the valve body (6) off a valve body seat (8) of the valve housing (3) to allow air to flow past the valve body (6) to the air outlet (5). Air pressure applied to the air outlet (5) can lift the valve element (7) off a valve element seat (9) of the valve body (6) to allow air to flow past the valve element (7) to the air inlet (4).

Abstract: A control unit of a pneumatic ride level control system of a motor vehicle, the control unit deactivating at least one function of the pneumatic ride level control system and/or activating at least one function of the pneumatic ride level control system if a limiting value of at least one dynamic-movement variable is exceeded or undershot, keeping the or each deactivated function deactivated for a defined holding time and/or keeping the or each activated function activated for a defined holding time duration after a subsequent undershooting or exceeding of the limiting value, and subsequently ending the deactivation of the or each deactivated function and/or the activation of the or each activated function after the respective holding time duration has elapsed, and the control unit defining the respective holding time duration as a function of the magnitude of the exceeding or undershooting of the respective limiting value.

Abstract: An air spring system is disclosed. The air spring system has a compressor, which has a suction side and a delivery side, a pressure reservoir, a first valve device and a second valve device. Each valve device is connected between the compressor and the pressure reservoir. In order to provide the air spring system, which is of simple construction and can be produced economically, the first valve device and the second valve device are each embodied as 3/2-way valves.

Abstract: A control unit of a pneumatic ride level control system of a motor vehicle, the control unit deactivating at least one function of the pneumatic ride level control system and/or activating at least one function of the pneumatic ride level control system if a limiting value of at least one dynamic-movement variable is exceeded or undershot, keeping the or each deactivated function deactivated for a defined holding time and/or keeping the or each activated function activated for a defined holding time duration after a subsequent undershooting or exceeding of the limiting value, and subsequently ending the deactivation of the or each deactivated function and/or the activation of the or each activated function after the respective holding time duration has elapsed, and the control unit defining the respective holding time duration as a function of the magnitude of the exceeding or undershooting of the respective limiting value.

Abstract: A residual pressure holding valve (1) for a hydropneumatic suspension strut (2) of a motor vehicle has a valve housing (3) with an air inlet (4) and an air outlet (5). A valve body (6) is arranged displaceably in the valve housing (3) and a valve element (7) is arranged displaceably in the valve body (6). Air pressure applied to the air inlet (4) can lift the valve body (6) off a valve body seat (8) of the valve housing (3) to allow air to flow past the valve body (6) to the air outlet (5). Air pressure applied to the air outlet (5) can lift the valve element (7) off a valve element seat (9) of the valve body (6) to allow air to flow past the valve element (7) to the air inlet (4).

Abstract: An air spring system is disclosed. The air spring system has a compressor, which has a suction side and a delivery side, a pressure reservoir, a first valve device and a second valve device. Each valve device is connected between the compressor and the pressure reservoir. In order to provide the air spring system, which is of simple construction and can be produced economically, the first valve device and the second valve device are each embodied as 3/2-way valves.