Abstract: An electronic antiskid control device which comprises a frequency multiplier of the phase locked-loop type, which receives repetitive pulses of predetermined frequency representing the speed of one wheel. The phase locked-loop multiplier normally outputs a second pulse signal, the frequency of which is normally equal to the frequency of the wheel speed signal multiplied by a given number. A digital counter which is periodically reset at a frequency equal to that of the wheel speed signal measures the number of pulses of the second pulse signal during each period. The measured number is transfered into a memory element and calculating apparatus responsive to the value stored in the memory element control an antiskid cycle. In operation under normal conditions, the number stored in the memory element is constant and has no action on the calculating apparatus.

Abstract: An electronic antiskid control unit for an adaptive braking system of the speed reference type wherein a signal for controlling decay of pressure is generated in response to comparison of the wheel speed signal with another signal. In a first phase, the wheel speed signal is compared with a reference signal derived from the wheel speed signal for generating the decay signal as long as the wheel speed reference signal is greater than wheel speed signal. At the end of this first phase, the wheel speed and speed reference signals have the same value and the speed reference signal is overridden by another increasing signal for comparison with the wheel speed signal thereby increasing duration of the decay. The other signal has three portions and is derived from a base signal having an exponential characteristic. At the end of the third portion, corresponding to intersection of the other signal with the wheel speed signal, the decay signal is extinguished.

Abstract: In an input control unit for a vehicle anti-skid braking system, a wheel-speed sensor delivers speed signals to the first input of a differential amplifier. Simultaneously, a capacitor is charged through a resistor and a diode. The capacitor is discharged at a constant rate into a device connected to the second input of the differential amplifier. Another diode prevents the voltage across the capacitor from becoming higher than the voltage of the speed signals. The braking pressure is released for the duration of output signals produced by the differential amplifier. The duration of these signals is kept within safe limits due to the fact that the additional diode limits the voltage across the capacitor.

Abstract: The invention relates to an electrical control unit for a wheeled vehicle. A decay valve is energized by means of a generator which delivers a control signal resulting from the comparison between a speed signal and a reference signal derived from the speed signal. An isolation valve is energized by the signal at the output of monostable apparatus having a predetermined time period and initiated by the leading edge of the control signal. The signal at the output of the monostable apparatus can be interrupted before the end of its time period upon generation of a signal resulting from comparison of the speed signal and a signal increasing linearly. The isolation valve is further controlled by the signal at the output of the generator and also a signal at the output of multivibrator apparatus.