Abstract: An improved wheel end valve assembly for a Central Tire Inflation System having a single connection to the tire chamber and a single connection to the source of pressurized fluid, which requires no venting other than through the single supply conduit, is effective in response to pressurization and venting of the supply conduit to open and close communication to the tire, and to isolate the tire if inflation pressure thereof falls below a minimum reference pressure. A controlled bleed of air between the control circuit and the isolation circuit is provided by a elastomeric disk shaped, one way valve having an orifice formed therein which is self cleaning when the valve is actuated.

Abstract: A central tire deflation system for emergency vehicles, such as fire trucks, rescue vehicles located at airports, enabling the operator to deflate all of the tires of the emergency vehicle to a predetermined minimum pressure while traveling to a crash site so that the "footprint" of the tires is increased at or about the time the vehicle reaches soft terrain. The minimum tire pressure is obtained by a minimum pressure valve which senses tire pressure as the tires are being deflated and stops deflation of the tires when the predetermined minimum pressure is sensed.

Abstract: A tire valve assembly (56, 58) for a central tire inflation system (10) effective to automatically isolate a tire (12) pressurized to less than a predetermined minimum pressure from the remainder of the system is provided. The tire valve assembly includes a control valve (58) and a low tire pressure shut-off valve (56) which are connected to a selectively pressurized and vented conduit (52) and to a conduit (68) fluidly communicating with the interior pressurized chamber (74) of the tire. A single selectively pressurized and vented conduit (52) operates the control valve and provides the sole connection of the assembly to pressurized fluid and/or to venting to atmosphere required for system operation other than for initial inflation of the tires to the predetermined minimum pressure thereof.

Abstract: A tire valve assembly (300) for a central tire inflation system (10) comprising a single valve body (302) having only a first (304) and a second (306) fluid connection from the exterior to the interior thereof is provided. The first fluid connection comprises a first port (304) connected to a selectively pressurized and exhausted conduit (52) and the second fluid connection comprises a second port (306) connected to the interior pressurized chamber (74) of an inflatable tire (12). The assembly includes first valve means (314) responsive to pressurization and exhausting of said selectively pressurized and exhausted conduit to establish or block, respectively, fluid communication between said first and second ports and second valve means (316) responsive to pressurization in said interior tire chamber to maintain said first valve means in the closed position thereof if said interior tire chamber is pressurized below a predetermined reference pressure.

Abstract: A modular tire valve assembly (11) for a central tire inflation system (10) comprising a valve body (212) having only a first (66) and a second (72) fluid connection from the exterior to the interior thereof is provided. The first fluid connection comprises a first port connected to a selectively pressurized and exhausted conduit (52) and the second fluid connection comprises a second port connected to the interior pressurized chamber (74) of an inflatable tire (12). The assembly includes first valve means (220) responsive to pressurization and exhausting of said selectively pressurized and exhausted conduit to establish or block, respectively, fluid communication between said first and second ports and second valve means (280) responsive to pressurization in said interior tire chamber to maintain said first valve means in the closed position thereof if said interior tire chamber is pressurized below a predetermined reference pressure.

Abstract: A central tire inflation system (10) comprising a pressure relief valve (180) fluidly interposed control means (142, 156, 164, 154, 172) and a tire valve assembly (56, 58) is provided. The control valve assembly is effective to selectively pressurize or exhaust a first conduit (170) connected to a first port (178) of the pressure relief valve, a second conduit (50, 52) extends from a third port (184) of the pressure relief valve to the tire valve assembly and a second port (182) is connected to atmosphere. The pressure relief valve is effective to establish fluid communication between said first and second ports thereof when the pressure in said first conduit exceeds the pressure in said second conduit and to establish fluid communication between the second conduit and the exhaust port (182) if the pressure in said second conduit exceeds the pressure in said first conduit.

Abstract: A vehicle air system (300) for a vehicle equipped with a source of pressurized fluid (302, 306), an air brake system (314), a central tire inflation system (316) and a central tire inflation system pressurized fluid reservoir (336) is provided. Preferably, the central tire inflation system reservoir is defined in part by the vehicle spare tire. The central tire inflation system rservoir is fluidly connected to the source of pressurized fluid, the vehicle air brake system and the central tire inflation system by a pair of parallel conduits (332, 334), one of which is provided with a one way check valve (340) allowing pressurized fluid stored in the reservoir to be supplied to the brake system of the central tire inflation system.