Abstract: The electric vehicle driven by a DC motor having a field winding. An electric resistance element can be switched into parallel circuit with the field winding to weaken the field and increase potential motor speed. A relay operates the switch, a Hall-effect switch responsive to motor rotation produces voltage pulses indicative of motor speed. A microcomputer counts pulses in a given time period to determine motor speed and compares the speed with that in the prior period to determine whether the motor speed is increasing or decreasing. The computer is programmed to operate the relay to close the switch as the motor speed increases above a first speed and to open the switch as motor speed subsequently decreases to a second speed lower than said first speed. The computer is programmed to respond to a third speed greater than the first speed to operate the relay to open said switch to prevent overspeed.

Abstract: A motor driven vehicle has a safety control preventing operation of the motor if the operator is not in the drivers seat to close a seat switch for a predetermined period of time. The motor includes an electric circuit which when complete enables motor operation and which prevents motor operation when the circuit is open. A microprocessor opens the circuit when the seat switch is open and is programmed to provide a predetermined time delay before opening the circuit to stop motor operation. The computer decrements the time delay whenever the seat switch is open. The computer includes means for testing to determine whether the time delay has been reduced to 0 at periodic intervals shorter than the predetermined time delay. The decremented time delay is restored to full value if the seat switch is closed during such testing before said time delay has been decremented to 0.

Abstract: A motor vehicle powered by a DC motor has a pedal which is depressed by the driver to increase speed by actuating a tapping switch which has two sets of moving contacts cooperating with stationary contacts to progressively connect with the motor batteries from one or the other end of a bank of series connected batteries. An alternate action relay connected between said motor and the switch determines which of the two sets is connected in circuit with the motor. The relay has two positions to alternately connect one or the other of the tapping switch contact sets in circuit with said motor. A main solenoid switch is connected in series with the relay and the tapping switch. When the pedal is depressed, a foot switch operated by the pedal is operative to close a circuit enabling energization of the alternate action relay and the main solenoid switch. A microprocessor controls operation of the relay and the main solenoid.

Abstract: Voltage is dropped across the variable reistance of a gas responsive sensor to obtain a control voltage which is compared to a ramp waveform reference to cause the comparator to apply pulses to an SCR which supplies corresponding charging pulses to the battery. Another embodiment uses the sensor resistance variation to decrease the current on the base of a transistor which controls the current supplied to the battery.

Abstract: Disclosed herein is a control for a hydrostatic transmission, which control includes a control member operatively connected to the transmission for selectively moving the transmission between forward, neutral and reverse positions in response to control member movement, a pivotally movable member, an actuating member mounted for movement between forward, neutral and reverse positions, means connecting the actuating member with the movable member for pivoting the movable member in response to actuating member movement and connecting the actuating member and the control member for moving the transmission between forward, neutral and reverse positions in response to actuating member movement, and first and second arms pivotally mounted coaxially with, and independently of, the movable member and having outer free ends located in spaced relationship to each other.

Abstract: Disclosed herein is a thyristor interlock circuit for energizing a DC motor, the circuit comprising a solenoid switch including an actuating coil, the solenoid switch and the motor being connected in series relation between the opposed terminals of the DC source, a thyristor having an anode, a cathode, and a gate, an ignition switch which connects the anode to one terminal of the DC source, a start switch normally biased to an open position, the start switch being linked to close after closing of the ignition switch, the start switch being connected to the one terminal of the DC source and to the gate, a resistor for limiting the gate current, a controller having a switch with two terminals, and a sub-circuit comprising a first lead including a first resistor and connecting the first resistor and the actuating coil in series relation between the thyristor cathode and the other terminal of the DC source, a second lead connecting one terminal of the controller switch to the start switch and the gate, a third le

Abstract: Disclosed herein is a direct current motor control circuit adapted for connection to first and second supply terminals of DC power source and to a DC motor connected between the positive and negative terminals of a DC power source, the control circuit including a solenoid including a solenoid coil having one end connected to the first supply terminal and having an opposite end, and having a pair of solenoid contacts connected in series relation with the DC motor between the positive and negative terminals and which close to energize the DC motor when current flows through the solenoid coil.

Abstract: Disclosed herein is a control for a direct current motor including a field weakening solenoid switch including a solenoid coil, which control includes a switch connected in series with a coil for connecting and disconnecting the coil to a source of direct current, and a device responsive to motor speed for operating the switch.Also disclosed herein is an overspeed control for a direct current motor including a solenoid switch which controls energization of the direct current motor, which is biased open, and which includes a solenoid coil operable in response to energization thereof to close the switch, which overspeed control comprises a switch connected in series with the coil for selectively connecting the coil to a source of direct current, and a device responsive to motor speed for operating the switch.

Abstract: Disclosed herein is a direct current motor control or energizing circuit comprising a direct current motor, a bank of series connected batteries, which bank includes opposite ends, and a switching arrangement for electrically disconnecting and connecting the bank to the motor for energizing of the motor at selective levels of potential and so that successive energizations involve alternate connection of the motor from the opposite ends of the bank to at least one of the batteries.

Abstract: Disclosed herein is a direct current motor control comprising a direct current motor, a solenoid switch including an actuating coil, a first lead connecting the drive motor and the solenoid switch in series relation to each other, a second lead connected to the motor and adapted to be connected to one terminal of a direct current source, a third lead connected to the solenoid switch and adapted to be connected to the other terminal of the direct current source, a sub-circuit assembly including the solenoid actuating coil and a solenoid coil actuating switch connected in series with each other, a fourth lead connected to the sub-circuit assembly and adapted to be connected to the one terminal of the direct current source, a solenoid latching switch connected to the sub-circuit assembly in series relation thereto and also connected to the third lead, a fourth lead connected to the sub-circuit assembly in series relation thereto and in parallel relation to the solenoid latching switch and also connected to the f

Abstract: Disclosed herein is a control comprising a rotatably supported wheel, a first direct current motor, means drivingly connecting the first direct current motor to the wheel with a first drive ratio, a second direct current motor, means drivingly connecting the second direct current motor to the wheel with a second drive ratio lower than the first drive ratio, a source of direct current, and a switch electrically connected to the source of direct current and to the first and second direct current motors and including a contact arm for initially electrically connecting the direct current source to the first direct current motor whereby to drive the wheel at a slow speed, and for subsequently additionally electrically connecting the source of direct current to the second direct current motor while maintaining electrical connection of the direct current source to the first direct current motor, whereby to drive the wheel at a fast speed.