Flywheel assisted electro-mechanical drive system

Claim 2

An electro-mechanical drive system for vehicles comprising: a planetary differential gear transmission having three separate shafts coupled respectively to a sun gear, planet gears and a ring gear; a propulsion drive shaft coupled to a first one of said shafts; a flywheel coupled to a second one of said shafts; a motor-generator coupled to a third one of said shafts and having the capability of operating as a motor to drive the third shaft and as a generator to develop an output current when driven by the third shaft, the motor-generator and the flywheel being the only sources of propulsion in said drive system; electrical storage means for supplying electrical energy to the motor-generator when operated as a motor and for receiving electrical energy from the motor-generator when operated as a generator; and electrical control means for selectively controlling the motor-generator to cause the flywheel to deliver driving power to the drive shaft.

Claim 3

The system of claim 1 wherein the control means further includes means for causing the planetary transmission to deliver power from the drive shaft to the flywheel during a regenerative braking mode.

Claim 4

The system of claim 1 or claim 2 wherein the control means includes means for limiting current flowing between the battery and the motor-generator to a level within a preselected range.

Claim 5

The system of claim 1 wherein the control means includes means for operating the motor-generator to cause the drive shaft to be driven in the reverse direction in response to operator command.

Claim 6

The system of claim 1 wherein the control means includes mode switching means for operating the motor-generator selectively in either a motoring or a generator mode.

Claim 7

The system of claim 1 wherein the first shaft is coupled to the planet gears, the second shaft is coupled to the sun gear, and the third shaft is coupled to the ring gear.

Claim 8

An electro-mechanical drive system for vehicles comprising: a planetary differential gear transmission having three separate shafts coupled respectively to a sun gear, planet gears and a ring gear; a propulsion drive shaft coupled to a first one of said shafts; a flywheel coupled to a second one of said shafts; a motor-generator coupled to a third one of said shafts and having the capability of operating as a motor to drive the third shaft and as a generator to develop an output current when driven by the third shaft; electrical storage means for supplying electrical energy to the motor-generator when operated as a motor and for receiving electrical energy from the motor-generator when operated as a generator; and electrical control means for selectively controlling the motor-generator to cause the flywheel to deliver driving power to the drive shaft; wherein the motor-generator is a separately excited DC machine having means for separately controlling the polarity and direction of current to a field winding thereof, and further comprising a mode switch connected between one side of the motor-generator armature and the battery with a current interrupting means connected between the other side of the motor-generator armature and the other side of the battery.

Claim 9

An electro-mechanical drive system for vehicles comprising: a planetary differential gear transmission having three separate shafts coupled respectively to a sun gear, planet gears and a ring gear; a propulsion drive shaft coupled to a first one of said shafts; a flywheel coupled to a second one of said shafts; a motor-generator coupled to a third one of said shafts and having the capability of operating as a motor to drive the third shaft and as a generator to develop an output current when driven by the third shaft; electrical storage means for supplying electrical energy to the motor-generator when operated as a motor and for receiving electrical energy from the motor-generator when operated as a generator; and electrical control means for selectively controlling the motor-generator to cause the flywheel to deliver driving power to the drive shaft; wherein the motor-generator is a separately excited DC machine having means for separately controlling the polarity and direction of current to a field winding thereof, and further comprising a mode switch connected between one side of the motor-generator armature and the battery with a current interrupting means connected between the other side of the motor-generator armature and the other side of the battery.

Claim 10

The system of claim 7 wherein the control means further comprises a driving stage coupled to the current interrupting means for selectively controlling the current interrupting means between on and off positions.

Claim 11

The system of claim 8 further including current sensing means connected in series with the armature, and a comparison stage coupled to receive input signals from the current sensing means and from a current control means for making a comparison between said two input signals and applying an output signal to control the driving stage.

Claim 12

The system of claim 9 wherein the control means further includes a first diode coupled between one pole of the armature and a corresponding terminal of the battery for conducting charging current to the battery when the current interrupting means is in the off condition and the motor-generator is being operated in a generating mode.

Claim 13

The system of claim 10 wherein the control means further comprises a free-wheeling diode connected in a circuit path across the armature to conduct armature current when the current interrupting means is in the off condition and the motor-generator is being operated as a motor.

Claim 14

The system of claim 7 further including reversible power supply means coupled to control the magnitude and direction of current in the motor-generator field winding in response to applied field current command signals.

Claim 15

The system of claim 12 further including means for controlling the mode switch between motoring and generating mode positions in response to applied command signals.

Claim 16

The system of claim 7 wherein the control means further includes selector means operable for selectively controlling armature current and field current in accordance with the conditions of associated accelerator, brake and forward/reverse switch devices.

Claim 17

The system of claim 14 wherein the selector means further includes means for monitoring speeds of the drive shaft, the flywheel and the motor-generator.

Claim 20

The method of claim 16 wherein the mode selecting step includes selecting the motor mode of operation, and further including periodically interrupting the current from the battery while permitting armature current to flow through a unidirectional bypass path and continuing to sense the level of armature current.

Claim 21

The method of claim 16 wherein the mode selecting step includes selecting the generator mode of operation, and further including permitting generated armature current to build up to a first preselected level, then interrupting one armature current path to divert induced current to the battery until the current drops to a second preselected level, and repeating the cycle in order to build up charge in the battery.