A velocity dependent flow control unit for an air spring. The velocity dependent flow control unit including a compression fluid pathway with a one-way valve and a rebound fluid pathway with a one-way valve. The velocity dependent flow control unit can be fixed and coupled between two additional air chambers of the air shock. A spring curve of said air shock can be dependent upon a velocity of a compression of the air shock and can be controlled by a flow rate of a fluid passing the two additional chambers and the velocity dependent flow control unit.

A multi-rate adaptive spring system. A first spring with a first spring rate. A second spring with a second adaptive spring rate. The second spring comprising a damper portion, a hydraulic piston, and an additional volume reservoir. The additional volume reservoir comprising a fluid filled portion, a gas filled portion, and a floating piston.

A velocity dependent flow control unit for an air spring. The velocity dependent flow control unit including a compression fluid pathway with a one-way valve and a rebound fluid pathway with a one-way valve. The velocity dependent flow control unit can be fixed and coupled between two additional air chambers of the air shock. A spring curve of said air shock can be dependent upon a velocity of a compression of the air shock and can be controlled by a flow rate of a fluid passing the two additional chambers and the velocity dependent flow control unit.

A suspension system configured to exhibit low variance in vehicle ride frequency over a large range of vehicle loads. The suspension system includes a strut having a cylinder and a piston configured to reciprocate in the cylinder. The suspension system also includes a vessel coupled to the strut, and a valve in an interior chamber of the vessel. The valve divides the interior chamber into a first liquid volume and a second liquid volume. The suspension system also includes a hydraulic accumulator having a volume and a liquid volume. The suspension system further includes a compressible liquid in the cylinder, the first liquid volume in the vessel, and the second liquid volume in the vessel, and a spring element in the volume of the hydraulic accumulator.

A suspension system configured to exhibit low variance in vehicle ride frequency over a large range of vehicle loads. The suspension system includes a strut having a cylinder and a piston configured to reciprocate in the cylinder. The suspension system also includes a vessel coupled to the strut, and a valve in an interior chamber of the vessel. The valve divides the interior chamber into a first liquid volume and a second liquid volume. The suspension system also includes a hydraulic accumulator having a volume and a liquid volume. The suspension system further includes a compressible liquid in the cylinder, the first liquid volume in the vessel, and the second liquid volume in the vessel, and a spring element in the volume of the hydraulic accumulator.

A method is for operating a compressed air system in a vehicle. The compressed air system has pneumatically operated actuators, switchable pneumatic valves and devices for supplying and preparing compressed air, which are connected to one another via a pneumatic line system. The devices for supplying compressed air include a compressed air source and a compressed air store, and in the line system a pressure sensor is provided for measuring the pressure. An algorithm is programmed such that depending on the difference between the pressure in the compressed air store and the pressure in the line system, pneumatic valves are actuated to connect the compressed air store to the line system only after pressure equalization between the pressure in the compressed air store and the pressure in the line system. During pressure equalization, compressed air from the source and/or the actuators or devices is introduced into the line system.

An air spring suspension system includes first, second, third, and fourth air spring assemblies configured to support a frame of the vehicle at front and rear suspension/wheel assemblies of the vehicle. A valve block includes a valve. A compressor supplies pressurized gas to the valve block. A reservoir is in fluid communication with the valve block. The air spring suspension system includes first, second, third, and fourth height sensors. First, second, third, and fourth variable flow valves are in fluid communication with the valve of the valve block and the first, second, third, and fourth air spring assemblies, respectively. A pressure sensor senses pressure in the valve block. A vehicle kinematic sensor senses a vehicle kinematic parameter. A controller is configured to control the first, second, third, and fourth variable flow valves in response to the pressure, the first, second, third, and fourth height sensors, and the vehicle kinematic parameter.

A suspension system configured to exhibit low variance in vehicle ride frequency over a large range of vehicle loads. The suspension system includes a strut having a cylinder and a piston configured to reciprocate in the cylinder. The suspension system also includes a vessel coupled to the strut, and a valve in an interior chamber of the vessel. The valve divides the interior chamber into a first liquid volume and a second liquid volume. The suspension system also includes a hydraulic accumulator having a volume and a liquid volume. The suspension system further includes a compressible liquid in the cylinder, the first liquid volume in the vessel, and the second liquid volume in the vessel, and a spring element in the volume of the hydraulic accumulator.

A pneumatic gauge and pressure control device includes a pneumatic gauge that is manually movable from a neutral position to: (i) a fill position for compressed air to flow from a compressed air source into a system; or (ii) a vent position for compressed air to be vented from the system. The pneumatic gauge can rotate or slide from the neutral position to the fill and vent positions. A method for controlling a flow of compressed air with respect to a pneumatic system includes manually moving a pneumatic pressure gauge from a neutral position to a fill position to cause compressed air to be communicated from an associated compressed air source into the pneumatic system and/or moving the pneumatic gauge from the neutral position or from the fill position to a vent position to cause compressed air to be vented from the pneumatic system.