Electric automobile

An electrically-driven vehicle comprising:

• an automobile frame having first and second drive wheels mounted thereon;
• first and second electric motors coupled to said first and second drive wheels, respectively;
• a battery for storing electrical energy that can be utilized to drive said first and second electric motors;
• and
• speed control means for controllably coupling the electrical energy stored in said battery to said first and second electric motors, said speed control means including
• an accelerator pedal,
• first coupling means for controllably coupling electrical energy from said battery to said first electric motor in accordance with the position of said accelerator pedal, and
• second coupling means for controllably coupling electrical energy from said battery to said second electric motor in accordance with the position of said accelerator pedal,
• wherein the amount of electrical energy coupled by each of said first and second coupling means is controllably adjusted to compensate for any variations in the relative efficiencies of said first and second motors, such that the respective torques produced by said first and second drive wheels are substantially equal.

A regenerative braking system for use in an electrically-driven vehicle of the type having a frame, first and second electric motors mounted on the frame and adapted to be driven in parallel to propel the vehicle, and energy storage means mounted on the frame for storing energy that can be utilized to drive the motors, said braking system comprising:

• a brake pedal mounted on the vehicle frame;
• means for producing a periodic control pulse signal having a duty cycle that varies in accordance with the position of said brake pedal;
• means for connecting said first and second electric motors in a series arrangement whenever said brake pedal is depressed, said series-connected electric motors functioning as an electric generator that can be utilized to controllably charge said energy storage means, thereby controllably braking the vehicle;
• and
• switch means responsive to the periodic control pulse signal for correspondingly coupling said series-connected electric motors to said energy storage means;
• wherein the degree of vehicle braking effected by said regenerative braking system is proportional to the duty cycle of the periodic control pulse signal.

An electrically-driven vehicle comprising:

• an automobile frame supported on a plurality of wheels;
• first and second direct-current electric motors, each of said motors adapted to drive a separate wheel;
• a battery for storing electrical energy that can be utilized to drive said first and second electric motors;
• speed control means for controllably powering said first and second electric motors, including
• an accelerator pedal,
• means for producing a first periodic control pulse signal having a duty cycle that varies in accordance with the position of said accelerator pedal, and
• first switch means responsive to the first periodic control pulse signal for transmitting electric current produced by said battery to said first and second electric motors, accordingly;
• and
• regenerative braking means utilizing said first and second electric motors as generators, for controllably braking the vehicle, including
• a brake pedal,
• means for producing a second periodic control pulse signal having a duty cycle that varies in accordance with the position of said brake pedal,
• means operable when said brake pedal is actuated, for inhibiting the transmission of electrical current from said battery to said first and second electric motors,
• means operable when said brake pedal is actuated, for connecting said first and second electric motors in a series arrangement, and
• second switch means responsive to the second periodic control pulse signal for utilizing electric current produced by said first and second electric motors to charge said battery, accordingly.