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: The present invention provides a dual-circuit hydraulic brake system, which has a hydrostatic circuit and a servo circuit. The brake system also has an electronic anti-locking system, which is fed by the servo circuit. To cut off the master cylinder in case of a controlled braking and thereby to guarantee a closed circuit, an annular receptacle in the servo cylinders used for circuit separation is connected to a volume receptacle in case of a braking controlled by the anti-lock system. At the sametime, the master cylinder is cut off by means of a central valve.

Abstract: A warning device for a pneumatic vehicle tire. The device includes a measurement unit which is mounted at the rim or at the wheel and which is connected with the inner space of the tire. A contact element penetrates the rim and points towards the inner surface of the tire which is opposite to the running surface, and which can be activated towards the inside of the wheel by allowing the inner surface to run against the rim surface. By activating the contact element, a nearly pressureless condition of the tire will be recorded.

Abstract: The present invention is a braking value transmitter with a pedal to modulate the braking pressure. The pedal is braced against a spring. The force exerted by the pedal or the position of the pedal is sensed by an electronic sensor. The output signal of the sensor is fed to an electronic system, which transforms the approximately linear characteristic of the sensor into a progressive characteristic.

Abstract: An apparatus which measures and regulates the braking torque of a brake unit in long-term operational use. The brake unit includes both a brakable element and the braking device. An output signal from at least one temperature-dependent measuring element, located on or in one of the brakable elements and the braking device, is supplied to an evaluation apparatus. The evaluation apparatus determines, from the current value of the output signal of the temperature-measuring element, a present braking torque, and adjusts such torque when desirable.

Abstract: An apparatus is disclosed for the control of brake pressure in a trailer pulled by a tractor. The apparatus includes a two-circuit controllable relay valve as the trailer control valve. The first circuit is controlled by the brake valve of the tractor with the pressure from the brake apparatus of such tractor. The second circuit can be optionally-connected to a distribution valve with a pressure medium source with a specified pressure or with atmosphere. Activation of the distribution valve is controlled so that the distribution valve connects the second circuit with the pressure medium source before or at the beginning of the activation of the first circuit. With this apparatus, the brake pressure can be increased in the brake apparatus of the trailer prior to increase of the brake pressure in the brake apparatus of the tractor. The level of brake pressure increased first in the brake unit of the trailer can be regulated by a set screw acting on the trailer control valve.

Abstract: A preselected parameter of the wheel brakes of a motor vehicle, to be equalized with respect to their braking force, is sensed. Such parameter is correlated with the amount of braking force being applied. A signal is generated by the preselected sensor, which is then used to control supplemental pressure-regulating valves, positioned in the brake pressure feed line to the respective wheel brakes. The parameter selected to be sensed can be, among other things, either the braking force or torque being applied or the wheel brake temperature.

Abstract: An improved arrangement for measuring and controlling the wear of the first member which is subject to wear during frictional contact with the second member. The unique arrangement employs a simple process which allows a direct measurement of wear with a minimum expenditure. The invention involves a method of measuring the temperature which is generated in the first member or in the second member or in an adjacent member, which is representative of the above-mentioned wear which occurs during frictional contact, and an evaluation circuit for converting the temperature values into wear signals.

Abstract: A protection circuit for monitoring and recognizing an undervoltage condition in the electrical system of a motor vehicle having an anti-skid brake control system in order to minimize and reduce any adverse effects on the braking action of the vehicle wheels. The protection circuit includes at least one comparator circuit to recognize if the voltage falls below a predetermined reference threshold voltage. When the supply voltage falls below the threshold voltage, the comparator circuit deactivates at least one of two diagonal switching circuits to remove automatic brakes on at least two wheels of a vehicle by the anti-skid brake control system.

Abstract: A transmission control is disclosed for a road vehicle for the determination of shift signals on downhill slopes. The invention includes a device for the determination of the stationary or constant speed drive torque M.sub.stat, which is necessary for the unaccelerated drive of the vehicle. The transmission control also includes a downhill gear classification device to coordinate the selection of a gear which is suitable for the downhill slope in question with a torque comparator in which various values of the stationary torque M.sub.stat are classified with the suitable downhill gear i.sub.x. A blocking element prevents a gear shift if a gear to be engaged by a shift command transmitter is higher than the suitable gear with the transmission ratio i.sub.x.

Abstract: A pneumatically controlled double seat relay valve including a housing for accommodating a reciprocating control piston having a first reactive surface acted upon by a source of control pressure and having a second reactive surface acted upon by a source of working pressure. A spring biasing valve piston slidably disposed in a tubular projection formed in the control piston. A spring biased slidable valve member disposed in a central bore formed in the housing and including an inlet valve cooperatively associated with an inlet valve seat formed by an annular lip of the central bore. An outlet valve seat carried by the slidable valve member and cooperatively associated with one side of the valve piston to initially close the outlet valve and subsequently open the inlet valve when control pressure is applied to the first reactive surface and for allowing the inlet valve to close when working pressure is applied to the one side of the slidable valve member to overcome the spring bias.

Abstract: A fluid pressure operated mechanism for a vehicular disk brake which includes two expansion elements capable of moving in opposite directions to each other. A compensating unit located between the two expansion elements to maintain a given stroke of the expansion elements and eliminate excess play which may be developed as a result of brake lining wear. The compensating unit takes the form of a one piece connecting link having return spring portions engaging one of the expansion elements and frictional gripping portions connected to the other of the expansion elements.

Abstract: A gear shift position sensing arrangement for a gear selector unit that selects the transmission gears indirectly. Magnetic sensors are arranged in the gear selector unit housing so as to be activated when a permanent magnet associated with the gear shift lever is brought into magnetic proximity therewith.

Abstract: A load-controlled brake pressure control unit for vehicle trailers including a load-weighing portion for operating a pressure control valve portion for effecting supply of brake-applying pressure via a relay valve according to vehicle load, a connection whereby brake-applying pressure is simultaneously supplied to the trailer brakes, and an emergency valve portion for effecting an emergency application in the event of separation or rupture of the trailer brake connecting line, all of the portions and components being housed in one casing.

Abstract: A gear shift mechanism for providing a vehicle operator with a "feel" of a desired gear change being completed in a power operated gear unit. A drum disc connected to the gear shift lever is formed with a recess in which a locking pin of an actuator valve is engageable when the gear shift lever is operated to a shift position, thereby limiting further movement of the gear shift lever. A sensor device associated with the gear unit detects completion of the gear change and operates the actuator to retract the locking pin from the recess to allow further movement of the gear shift lever, as an indication to the vehicle operator that the intended gear change is completed, so that he may engage the clutch and apply gas.

Abstract: A wheel anti-skid brake control system for controlling the braking effort of the four wheels of a motor vehicle. The system includes a speed sensor, an electronic evaluating circuit, a monitoring safety circuit, a switching device and a solenoid regulated valve for each wheel for deactivating the braking effort of a pair of diagonally opposed wheels when a malfunction occurs in an associated electronic evaluating circuit.

Abstract: A load-dependent braking force control device operable responsively to initial brake actuating pressure for initiating a light brake application until such pressure attains a certain predetermined higher valve, whereupon the control device, which is subject to a control pressure reflecting vehicle load, responds to such vehicle load control pressure for effecting a brake application accordingly. A piston for operating a fluid pressure supply and cut-off valve is subject on one side to fluid pressure supplied to the brake cylinders and on the opposite side to the same pressure communicated thereto via an adjustable pressure-limiting valve device, thereby determining the cut-off degree of the brake cylinder pressure.

Abstract: A dual-circuit, hydropneumatic brake conytrol system having a load proportioning function wherein the load condition sensed at the rear axle establishes the braking level at both axles. The front axle brake control is adjusted through either a pneumatic or hydraulic connection with the rear axle load control device. By making the operator's brake valve hydraulic, it can be isolated from the remaining hydraulic and pneumatic brake control components, in order to minimize the amount of space required in the operator's cab to accommodate the brake valve.

Abstract: A wheel spin control circuit which utilizes conventional anti-skid control apparatus for automotive-type vehicles including an operator's brake valve, brake cylinders, wheel speed sensors, wheel behavior evaluation circuitry and modulator valves to apply braking pressure to a sensed spinning wheel. A solenoid-operated control valve in parallel with the brake valve between the system air reservoir and modulator valves is actuated via a pushbutton switch whenever the operator senses a spinning wheel during acceleration to connect reservoir air to the modulator valves. The modulator valve of the slipping wheel is actuated by control signals emitted by the wheel behavior evaluation circuit to admit the reservoir air to pass to the brake cylinder of the spinning wheel to effect braking thereof. The pressure supply may be continuous or pulsed with or without a pressure-holding cycle.

Abstract: A disk brake assemblage providing an improved arrangement whereby the brake pads and supports therefore may be changed with a minimum amount of disassembly of the disk brake assemblage. The brake assemblage is provided with an annular cylinder and an annular piston operable therein and comprising a brake cylinder device operably disposed between a pair of backing plates and brake pads which are adapted to frictionally engage respective brake disks or rotors. Both the cylinder and the piston are provided with axially projecting lugs or members normally engaging correspondingly formed recesses on the brake pad backing plates for retaining the brake pads and plates in the operable position. By axially squeezing or displacing the cylinder and piston toward each other, the lugs are displaced out of the recesses to permit the brake pads and backing plates to be removed and replaced.