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 fire truck comprises an uninterrupted chassis frame carrying a driver's cab and supported on four driving axles arranged in 8.times.8 configuration and driven independently. The driving axles support the chassis frame via pressure fluid springs at opposite sides of the vehicle, the forward and rearward pairs of axles and associated springs defining forward and rearward undercarriages and the chassis carrying quenching agent tanks, a quenching agent pump, and a driving engine. The fluid pressure springs at one side of the vehicle are connected via a pressure fluid supply system and a load compensator system to the springs at the opposite side. An automatic transmission is positioned between the forward and rearward undercarriages and the driving axles are individually coupled thereto. The automatic transmission is coupled to the driving engine which is situated in the chassis frame above the rear undercarriage.

Abstract: A system for automated pressurization of pneumatic tires includes an air pump which is driven by the vehicle engine and provides a continuous output of pressurized air. The pressurized air can either be routed to the tires or vented to the atmosphere under control of a manually-actuated selector valve having inflate, neutral and deflate modes of operation. A second selector valve can be set to designate which of the vehicle tires are to be inflated or deflated.

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.

Abstract: An automatic tire inflation/deflation system for a vehicle with pneumatic tires. The system may be incorporated into existing vehicles without modification of the axles, wheels or tires. A pressure-responsive bellows is utilized at each wheel to open or close the existing tire valve in accordance with air pressure values applied to the bellows exterior surface. A selector valve at the driver's station permits the human driver to remotely control the tire inflation or deflation process. During normal run operations, the air passage system is depressurized.

Abstract: A highly accurate pressure control system (200) adapted to control fluid pressure in apparatus such as the air pressure in vehicle tires (136) comprises a control module (210) having an air pressure selector (211) for selecting a desired air pressure and a pressure to voltage transducer circuit (230) for generating a signal representative of the actual air pressure. Signals representative of the difference between actual and desired air pressure are applied to comparator circuitry (246, 248) which control output switches (254, 256) for activating an inflate/deflate valve (220) to inflate or deflate the tires (136) so as to achieve and maintain the desired air pressure. Various circuitry of the control module (210) employ reference signals maintained at reference values held constant relative to a common power supply voltage instead of to a ground reference (218), thus minimizing circuit count and power dissipation while providing sufficient current for operating output switches (254, 256).

Abstract: A kit for retrofitting a vehicle to include an automatic tire inflation system is disclosed. The kit includes a control box for mounting within the cabin of the vehicle. The control box includes a selector device that is manually actuable by the operator to select the desired pressure for the tires. A valve is used to inflate or deflate the tires as a function of the pressure differential between the actual and the desired tire pressures. In the preferred embodiment, the actual tire pressure is monitored by way of a static pressure tank connected to the tires through a fixed orifice. The kit permits a manufacturer to mass produce a certain vehicle and then selectively choose which ones of the vehicles are to be provided with an automatic tire inflation system.

Abstract: A tire-pressure regulating system is proposed with which the air pressure in the vehicle tires can be varied while driving. The tires are connected to supply lines in which rotor connections, control valves, flow restrictive elements and an adjustable regulating valve are disposed. A relay valve and an axle valve are incorporated following the regulating valve.By means of guiding the supply line in and at the axle valve in a particular manner, an acceleration of the pressure equalization process is attained.The tire-pressure regulating device is preferably usable in trucks and trailer trucks.

Abstract: An automatic tire inflation system for a vehicle (10) includes a plurality of wheel assemblies (14). Each wheel assembly includes a rotatable portion (30) connected to its associated tire (16) and a non-rotatable portion (24) connected to the vehicle chassis (28). A sealed air passageway is provided between an inlet (62) in the non-rotatable portion and an outlet (64) in the rotatable portion of the wheel assembly which is connected to the tire. The sealed air passageway is provided in part by way of a longitudinally extending bore (66) in the spindle (24) which communicates with a chamber (60) defined by a sleeve (42) and a pair of air seals (52, 54) between the sleeve and spindle. A manually actuable selector device (102) in the vehicle is provided to permit the user to select one of a plurality of preset air pressure settings for the tires.

Abstract: A source of relatively high air pressure is connected to a pressure regulator which provides a lower relatively uniform predetermined pressure to a plurality of tires on wheels of a vehicle. If the pressure in any one of the tires drop below the others, the pressure from the regulator automatically brings it up to the uniform pressure.

Abstract: In cross-country vehicles where it is desirable to change the pressure in the pneumatic tires of the vehicle to fit the terrain, means are provided for changing the pressure on the tires without leaving the seat of the vehicle. The means provided in this disclosure comprise a source of compressed air, air control valves for each wheel of the vehicle, control keys including a magnetic valve, etc., for venting air from or forcing air to the tires, all somewhat similar to the arrangement disclosed in (Ger) DE-OS No. 2,141,553 but the sensitive throttle added to the latter disclosure is omitted and instead, a relief valve is provided for the air control valve of the wheels whereby the venting time is shortened and less of the apparatus as a whole is maintained under high pressure.

Abstract: A traction device for a motor vehicle comprising a hose connecting the vehicle's exhaust pipe to an air pressure pump inlet. The outlet of the pump is detachably connected to the inlet valve of the vehicle's tire. An outlet valve for exiting cold air is connected to another hose communicating with a temperature gage and a pressure gage.

Abstract: Apparatus for remotely controlling the internal pressure in a pneumatic tire, in which the inside of a pneumatic chamber mounted on a wheel is divided into a first chamber communicating with a fluid-supply source and a second chamber communicating with an air space in the tire by a diaphragm made of a flexible material. In an operation controlled from a vehicle cab, a fluid is introduced into the first chamber, thus compressing the second chamber so as to change the volume thereof, and thereby control the pressure in the air space with the tire by controlling the pressure in said second chamber.