Abstract: An apparatus is furnished for sensing the tire pressure and for generating a signal by way of an actuator. If the tire pressure drops below the predetermined reference tire pressure, then this is signalled immediately and instantly within a relatively small pressure tolerance threshold. The pressure sensitive device 1 includes a valve device 7. The valve device 7 connects the tire pressure, applied to the actuator 4 and acting against the force of the compression spring 6, to the atmosphere if the tire pressure drops below a predetermined reference tire pressure. The apparatus is suitable for generating a permanent signal, even in case no further pressure remains in a tire.

Abstract: A dual circuit brake valve system comprises first and second brake circuits, first and second combined inlet and outlet valves through which first and second braking pressures respectively are delivered to said first and second brake circuits, and first and second pistons which actuate the first and second combined inlet and outlet valves respectively. The second piston is actuated by the first braking pressure which serves as a control pressure therefor. To achieve simultaneous actuation of the first and second combined inlet and outlet valves, a compression spring is installed between the first and second pistons and mechanically connects these to each other. Thereby, a pressure difference of .DELTA.p between the pressure in the first brake circuit and the pressure in the second brake circuit, which approaches zero, is achieved. In order to be able to increase the pressure difference .DELTA.p in the two brake circuits, a third piston is provided between the first and second pistons.

Abstract: A device for monitoring the sealing properties of a gas-filled chamber is provided. The temperature-sensitive device is formed out of a thermally-reacting element (14, 19, 20, 24). The element changes its dimensional length depending on a temperature change. The element (14, 19, 20, 24) is disposed between a pressure measurement device (6, 11) and a valve (7, 8; 9, 10), serving as a signal generator. The device can be used for a monitoring of the pressure in a vehicle tire or of the gas density in a vehicle tire.

Abstract: The invention device monitors the pressure of a measurement chamber subjected to the pressure prevailing in a vehicle tire. A pressure-sensitive device scans the tire pressure with a pressure measurement member in a measurement chamber. In case of a tire-pressure drop, the tire pressure is used to actuate an auxiliary actuator (3, 24, 26). The auxiliary actuator genrates the regulating distance (s) dependent on a tire pressure drop below a pressure value required for an actuation of the actuator (13). The regulating distance (s) is recognizable by a sensor. The invention device is suitable for providing a permanent signal even in case of an absence of pressure in the measurement chamber (21).

Abstract: A device for the surveillance of the pressure of a vehicle tire includes a pressure-sensitive device which senses the tire pressure and generates, in case of a pressure loss in the tire, a pressure change signal. A set member is actuated with this pressure change signal such that the signal member performs a stroke. A sensor tests the position of the set member and recognizes when the tire pressure is too low. A pressure-sensitive device (1) includes a check valve (9, 12), opening toward the pressure discharge port (3). The pressure at the pressure discharge port (3) can be blocked versus the tire pressure based on the check valve (9, 12). The invention device is suitable for furnishing a continuous signal up to the complete emptying of a tire.

Abstract: A relay valve device having a first control surface and a second control surface. A shut-off device is located in the line feeding the control pressure into the second control surface throughout the period in which a signal pressure is present, and connecting the second control surface to atmosphere at other times. Thus, the relay valve device releases a greater pressure into a load circuit when actuated during effectiveness of the signal pressure than while the signal pressure is not effective. The shut-off device having a pressure relief valve with a switch-off device so that when the signal pressure is effective, the switch-off device switches OFF the pressure relief function of the pressure relief valve and so that when the signal pressure is not effective, the pressure relief valve is opened as long as the control pressure remains below the relief pressure and is closed when the control pressure moves above the relief pressure.

Abstract: A steering-brake control system for a vehicle in which solenoid operated control valves associated with the respective wheels of at least one axle are normally maintained in an open position, so long as the valve solenoid operators are deenergized. Braking pressure is produced when either one of a right and left brake pedal is operated. Switches associated with each pedal are effective to energize the solenoid of one wheel control valve to cut off brake pressure to that particular wheel, so that only the one wheel corresponding to the operated brake pedal is braked to cause the vehicle to turn in that direction for steering control in off-street operation. In the event both brake pedals are operated, the switches and valves operate to admit brake pressure to each wheel brake cylinder for normal braking during on-street operation.