Circuit arrangement for the regulation of the transmission stages on an automatic gear changer

Claim 1

Arrangement for the regulation of the points of shift between the transmission stages of an automatic gear changer of a motor vehicle provided with an accelerator and said automatic gear changer, comprising a direct current voltage supply source, a pick-up device responsive to the speed of the vehicle, a monostable circuit comprising a first, input transistor and a second, upput transistor, means electrically connecting the output of the pick-up device to the base of the first transistor, circuit means comprising a condenser and a variable resistor for determining the time constant of the resistor for determining the time constant of the monostable circuit, the variable resistor being provided with a sliding contact mechanically connected to the accelerator of the vehicle, means electrically connecting the full resistance of the variable resistor across the opposite terminals of the voltage supply source, a filter having an input and an output, means electrically connecting the collector of the second transistor to the input of the filter and to the positive terminal of the voltage supply circuit, a logic circuit having two inputs and an output, a source of a reference voltage for the shifting of the gear changer from one stage to another connected to one of the inputs of the logic circuit, the other of the inputs of the logic circuit being connected to the output of the filter, the logic circuit being adapted to compare the output voltage of the filter with the reference voltage, the collector of the first transistor being connected by a circuit including a series connected diode and a condenser with the base of the second transistor, circuit means connecting the base of the second transistor with the positive terminal of the voltage supply source, the cathode of the diode being electrically connected to the collector of the first resistor, the junction point between the diode and the condenser being electrically connected to the positive terminal of the voltage supply source, and the sliding contact of the variable resistor being electrically connected to the positive terminal of the voltage supply source, and means for varying the speed at which the automatic gear changer changes from said one stage to said other stage thereof, said last-named means being electrically connected to and controlled by the output of the logic circuit.