A system for filling a tank of a suspension system with hydraulic fluid includes: a module configured to turn on an external pump and pump hydraulic fluid into the suspension system, where the external pump is separate from the suspension system and is configured to pump hydraulic fluid into the suspension system via a port fluidly connected to a hydraulic line of the suspension system; and a fill module configured to, after operating the external pump, operate a pump of the suspension system and pump hydraulic fluid from the hydraulic line into the tank of the suspension system thereby filling the tank.

A system for filling a tank of a suspension system with hydraulic fluid includes: a module configured to turn on an external pump and pump hydraulic fluid into the suspension system, where the external pump is separate from the suspension system and is configured to pump hydraulic fluid into the suspension system via a port fluidly connected to a hydraulic line of the suspension system; and a fill module configured to, after operating the external pump, operate a pump of the suspension system and pump hydraulic fluid from the hydraulic line into the tank of the suspension system thereby filling the tank.

An abnormality detection method for a vehicle body tilt control device makes it possible to determine which air spring has an air supply/exhaust abnormality. A model creation step prepares a state estimation model for each of the front and rear vehicle halves into which a vehicle is divided, and an abnormality detection step applies a state estimation technique to the state estimation model to detect which one of the air springs has an air supply/exhaust abnormality. When flow rate command values for air supplied to/exhausted from the air springs included in each vehicle half are input, each of the input flow rate command values for air supplied to/exhausted from the air springs is multiplied by a virtual gain and the results are averaged. Based on the averages, the average of the heights of the air springs is output, where each virtual gain is included as a state variable.

In one embodiment, a suspension system for a vehicle cab, the suspension system comprising: a structural assembly; a cab mounted to the structural assembly; and plural suspension units arranged between the cab and the structural assembly, the plural suspension units comprising, fore and aft, a first pair of suspension units and a second pair of suspension units, wherein a lateral distance between the second pair of suspension units is greater than a lateral distance between the first pair of suspension units.

A wheel load adjusting apparatus used in a railcar, and the railcar includes: first and second air springs arranged between a carbody and a first bogie so as to be spaced apart from each other in a car width direction; third and fourth air springs arranged between the carbody and a second bogie so as to be spaced apart from each other in the car width direction; and first to fourth automatic level controlling valves provided upstream of the first four air springs and configured to adjust heights of the four air springs to maintain constant height of the air springs, wherein when the railcar passes through a curve, the wheel load adjusting apparatus limits an air supply/air discharge operation of at least one of the four automatic level controlling valves to suppress an increase in a pressure difference between at least two of the four air springs.

An air spring includes a closing member, a rolling piston, and an air spring bellows connected to the rolling piston and the closing member to form a fluid-filled pressure chamber. A level control system for supplying and/or discharging fluid may be integrated into the pressure chamber to control level position based on air spring stroke. The level control system may have a control valve and an actuator connected to the control valve. The actuator may include a guide tube coupled to the rolling piston or closing member, and movably arranged within the pressure chamber. An actuating member may include a pin member and may operate the control valve. A compression spring may have a central spring and a biasing spring, and the guide tube may include a control flange coupled to the pin member, and the biasing spring may be supported to press the pin member against the control valve.

In one embodiment, a suspension system for a vehicle cab, the suspension system comprising: a structural assembly; a cab mounted to the structural assembly; a front axle coupled to the structural assembly; plural suspension units arranged forward of the axle and disposed between the cab and the structural assembly; and plural isolation mounts arranged rearward of the axle and disposed between the cab and the structural assembly.

In one embodiment, a suspension system for a vehicle cab, the suspension system comprising: a structural assembly; a cab mounted to the structural assembly; and plural suspension units arranged between the cab and the structural assembly, the plural suspension units comprising, fore and aft, a first pair of suspension units and a second pair of suspension units, wherein a lateral distance between the second pair of suspension units is greater than a lateral distance between the first pair of suspension units.

An air suspension system which uses software logic and internal signals and/or external signals available to automatically adjust the ride height of the vehicle. The air suspension system also may respond to requests from other vehicle systems requesting a change in ride height. Signals available to the vehicle may be used to detect parking lot maneuvers (for example, a combination of low speed, high steering angle, and low lateral acceleration) and automatically begin to lower the ride height of the vehicle to a calibrated entry/exit ride height. Additionally, a camera, radar, and/or parking sensor signals are utilized to detect potential roof or undercarriage clearance issues, and automatically adjust the ride height of the vehicle. The air suspension system may also adjust the ride height of the vehicle when the electronic brake system (EBS) detects rough road, automatically increasing the ride height of the vehicle to increase ground clearance.

An air spring includes a closing member, a rolling piston, and an air spring bellows connected to the rolling piston and the closing member to form a fluid-filled pressure chamber. A level control system for supplying and/or discharging fluid may be integrated into the pressure chamber to control level position based on air spring stroke. The level control system may have a control valve and an actuator connected to the control valve. The actuator may include a guide tube coupled to the rolling piston or closing member, and movably arranged within the pressure chamber. An actuating member may include a pin member and may operate the control valve. A compression spring may have a central spring and a biasing spring, and the guide tube may include a control flange coupled to the pin member, and the biasing spring may be supported to press the pin member against the control valve.