Central tire inflation system
AssigneePACCAR Inc
InventorsRolland A. Magnuson, Robert G. Shires
Life of this patent
Estimating the term…
Abstract
A central tire inflation and deflation system which quickly inflates or deflates tires to any one of a plurality of pressures selected by the vehicle operator. Inflation pressure is greater than the pressure to which the tires are to be inflated. The system uses a tire valve which deflates the tires when a pressure less than the instantaneous tire pressure but greater than a minimum value is applied to the valve. Pressure on rotary seals which connect the tires to the system is relieved when the system is not operating.
Claims19
A central tire inflation system for a vehicle of the type having pressurized tires and utilizing one rotary air seal on an air passageway between each tire and a pressure source, comprising:
- means for selecting one of a plurality of different control pressures, each less than the source pressure;
- a pressure monitoring vessel having means for simulating the inflation and deflation characteristics of the tires;
- means for comparing pressure in the pressure monitoring vessel to the selected control pressure;
- a valve, fluidly connected between each of the tires and the corresponding rotary seal, and the pressure monitoring vessel and the air passageway, respectively having deflation means responsive to the application of pressure less than the instantaneous tire pressure, for quickly depressurizing the tires and pressure monitoring vessel by using the full pressure differential between the instantaneous tire pressure and atmospheric pressure and having inflation means responsive to the application of pressure greater than the instantaneous tire pressure, for pressurizing the tires and pressure monitoring vessel;
- means, responsive to the pressure comparison means, for applying the source pressure to the air passageway to activate the valve and quickly pressurize the tires and the pressure monitoring vessel approximately to the selected control pressure and for regulating the source pressure to the selected control pressure and applying the regulated source pressure to the air passageway to activate the valve and depressurize the tires and pressure monitoring vessel approximately to the selected control pressure;
- and
- means responsive to the pressure comparison means, for venting the air passageway to atmospheric pressure after the pressure in the pressure monitoring vessel becomes approximately equal to the selected control pressure.
A central tire inflation system for use on a vehicle of the type having pressurized tires and utilizing one rotary air seal on an air passageway between each tire and a pressure source and a valve actuated by applying pressure to the air passageway, comprising:
- means for selecting one of a plurality of different control pressures, each less than the source pressure;
- a pressure monitoring vessel having means for simulating the inflation and deflation characteristics of the tires;
- means for comparing pressure in the pressure monitoring vessel to the selected control pressure;
- means responsive to the pressure comparison means for applying the source pressure to the air passageway to quickly pressurize the tires and the pressure monitoring vessel approximately to the selected control pressure and for regulating the source pressure to the selected control pressure and applying the regulated source pressure to the air passageway to depressurize the tires and pressure monitoring vessel approximately to the selected control pressure;
- and
- means responsive to the pressure comparison means, for venting the air passageway to atmospheric pressure after the pressure in the pressure monitoring vessel becomes approximately equal to the selected control pressure.
Dependencies are inferred from the claim text.