A vehicle height control system and method of increasing a vehicle height of a vehicle having a vehicle body and at least one axle assembly. The vehicle height control system includes a pressurized fluid, and a plurality of air springs provided to support at least one section of the body of the vehicle above at least one axle of the vehicle and configured to adjust the height the vehicle relative to the ground in response to the supply and discharge of the fluid. A control assembly of the vehicle height control system configured to receive user input indicative of a vehicle height adjustment operation desired by a user has a piston unit fluidically interconnected with the pressurized fluid supply system via a first control valve and is operable to adjust the vehicle height by adjusting a second control valve interposed between the pressurized fluid supply system and the air springs.

A vehicle height control system and method of increasing a vehicle height of a vehicle having a vehicle body and at least one axle assembly. The vehicle height control system includes a pressurized fluid supply system configured to supply a pressurized fluid, and a plurality of air springs provided to elastically support at least one section of the vehicle body of the vehicle above at least one axle assembly of the vehicle and configured to adjust the vehicle height of such sections of the vehicle body relative to a ground surface in response to the supply and discharge of the pressurized fluid. A control assembly of the vehicle height control system has a piston unit fluidically interconnected with the pressurized fluid supply system via a first control valve and is operable to adjust the vehicle height by adjusting a second control valve interposed between the pressurized fluid supply system and the air springs. A controller is configured to receive user input indicative of a Vehicle height adjustment operation desired by a user and to adjust the vehicle height by controlling the control assembly based on the user input.

A vehicle height adjustment system includes: a cylinder housing part having an inner space configured to receive working fluid; a piston part positioned in the cylinder housing part, the piston part configured to move linearly, in response to a working fluid, in a moving direction along the cylinder housing part; and a rotation suppressing bracket coupled to the cylinder housing part and connected to a side surface of the piston part, the rotation suppressing bracket configured to suppress rotational movement with respect to the moving direction of the piston part.

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.

A method for operating a pneumatic system having a compressed air supply system and an air spring system includes determining at least one deflection of at least one air spring of the pneumatic system. The air spring is configured to be connected to a gallery in a selectively gas-conveying manner via a valve. The method further includes determining at least one bellows volume of a spring bellows of the at least one air spring based on the at least one determined deflection, indicating a pneumatic surrogate model for the at least one bellows volume and/or for a pressure accumulator volume of a pressure accumulator of the pneumatic system based on a mass flow balance for a balance volume, and calculating, based on the pneumatic surrogate model, at least one pressure value of the at least one bellows volume, the pressure accumulator volume, and/or the balance volume.

A primary air suspension system with the reliability of a secondary air suspension system by guaranteeing a minimum pressure in the air spring through a simple mechanical residual pressure valve. The residual pressure valve is set to the air spring pressure required to hold the rear of the unloaded pickup truck at the designed ride height if any of the components (compressor, tank, valves, air lines, Schrader valve, or electronic controller) failure.

A hydraulic actuator for a vehicle suspension includes: a pump assembly including an electric motor coupled to first and second pumps to transfer hydraulic fluid to a discharge header; a first isolation valve having an elastomeric seat and configured to selectively block fluid flow from a port in fluid communication with a height-adjustable damper to the discharge header; and a second isolation valve having a metal seat and connected in series with the first isolation valve to selectively block fluid flow from the port to the discharge header. The first pump transfers hydraulic fluid from a supply fluid passage to a first discharge header, and the second pump transfers hydraulic fluid from the supply fluid passage to a second discharge header. A recirculation valve selectively controls fluid flow from the second discharge header to the supply fluid passage.

A vehicle height adjustment system includes: an input housing part having a space in which working fluid is stored; an input piston part positioned in the input housing part, the input piston part configured to move along a lengthwise direction of the input housing part; a lead screw inserted into the input piston part, the lead screw configured to move in response to receiving external power; and a connection part fastening the input piston part with the lead screw.

Systems and methods for load monitoring and/or braking control. The load monitoring may include calculating a weight on one or more axles of a vehicle or a trailer using cross-flow pressure information indicative of an air pressure within a cross-flow passage between first and second leveling valves of first and second pneumatic circuits configured to adjust independently heights on first and second sides, respectively, of the vehicle or the trailer. The braking control may include (i) using the cross-flow pressure and speed and/or acceleration information indicative of a speed and/or acceleration of the vehicle and/or the trailer to calculate first and second brake application levels and (ii) applying the calculated first and second brake application levels to first and second brakes on the first and second sides, respectively, of the vehicle or the trailer.

A bed truck having multiple axles has a hydraulic suspension including multiple hydraulic cylinders for each axle, a ride height sensor associated with each hydraulic cylinder, a high pressure hydraulic circuit connecting each of the cylinders and accumulators to a hydraulic pressure source, a low pressure hydraulic circuit connecting each of the cylinders to a fluid tank, and a plurality of valves operable to isolate operation of any one hydraulic cylinder from some or all of the other hydraulic cylinders. A control system is operable to control each of the hydraulic cylinders, either independently of all the other hydraulic cylinders, or in concert with one or more other hydraulic cylinders, such control including locking any one or more of the hydraulic cylinders at a minimum ride height position.