Electric riding lawn mower powered by an internal combustion engine and generator system

• US 6,591,593 B1
• Filed: 10/23/2000
• Issued: 07/15/2003
• Est. Priority Date: 10/23/2000
• Status: Expired due to Fees

• Current Assignee: International Consortium, Inc.
• Original Assignee: International Consortium, Inc.
• Inventors: Brandon, Dennis, Flack, Allan
• Primary Examiner(s): Pezzuto, Robert E.
• Assistant Examiner(s): PETRAVICK, MEREDITH C
• Application Number:
  US09/694,646
• Time in Patent Office: 995 Days
• Field of Search: 56/106, 56/102.G, 56/108, 56/111, 56/119, 56/171, 180/165, 180/900
• US Class Current: 56/10.6
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/006 Control or measuring arrangements
• CPC Class Codes: A01D 34/6806 Driving mechanisms for the cutters A01D34/76
• CPC Class Codes: A01D 34/78 electric
• CPC Class Codes: A01D 69/02 electric
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/44 Series-parallel type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60W 2300/156 Ridable lawn mowers
• CPC Class Codes: B60Y 2200/223 Ridable lawn mowers
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/906 Motor or generator
• CPC Class Codes: Y10S 903/916 with plurality of drive axles

Abstract

An electric riding mower which integrates an electric generator and inverter driven by an internal combustion engine, an operator/drive with an electric motor driving each of the two wheels and a mowing deck that has electric motors driving the cutting blades and a motor for raising/tilting the deck is disclosed. The generator is mechanically driven by the output shaft of an internal combustion engine to generate the electrical power for energizing the electric motors and the inverter. A computer in the master controller communicates with each of the controllers for the motors and the generator/inverter and processes the data necessary to co-ordinate the drives.

Claims

1. A riding lawn mower, comprising:

a fuel combustion engine;

an electrical generator operatively connected to the fuel combustion engine;

a first electric drive motor electrically connected to the electric generator and adapted to propel the riding lawn mower;

a controller adapted to generate an inverter control signal to control the frequency and output voltage level of the inverter; and

an electrical signal inverter electrically connected to the electrical generator and adapted to receive the inverter control signal and generate a power output.

2. The riding lawn mower of claim 1, the electrical signal inverter comprising:

a programmable logic device adapted to receive the inverter control signal and generate pulses according to the inverter control signal by varying the pulse width and frequency of pulses;

an h-bridge for converting the pulses to a waveform; and

a smoothing low pass filter adapted to smooth the waveform to produce the power output.

3. A riding lawn mower, comprising:

a fuel combustion engine;

an electrical generator operatively connected to the fuel combustion engine;

a first electric drive motor electrically connected to the electric generator and adapted to propel the riding lawn mower; and

support feet adapted to be placed in an up position and a down position, wherein when the support feet are in the down position the generator is supported by the support feet.

4. The riding lawn mower of claim 3, further comprising an electrical disconnect electrically connected between the generator and the drive motor and adapted to removably connect the generator and the drive motor.

5. The riding lawn mower of claim 3, comprising

an electrical signal inverter electrically connected to the electrical generator, wherein the inverter is adapted to be operated as a stand-alone power source after the support feet have been placed in the down position.

6. A riding lawn mower, comprising:

a fuel combustion engine;

an electrical generator operatively connected to the fuel combustion engine;

a first electric drive motor electrically connected to the electric generator and adapted to propel the riding lawn mower;

a first driven wheel mechanically coupled to the first drive motor;

an operator interface device adapted to generate an input signal;

a driven wheel controller electrically connected to the operator interface device and adapted to receive the input signal and generate a first motor control signal;

a first drive motor controller electrically connected to the first drive motor and the driven wheel controller and adapted to receive the first motor control signal, the first drive motor controller further adapted to control the speed of the first driven wheel in accordance with the first motor control signal;

a second driven wheel adapted to drive the mower;

a second drive motor adapted to drive the second driven wheel;

the driven wheel controller further adapted to generate a second motor control signal; and

a second drive motor controller electrically connected to the second drive motor and the driven wheel controller and adapted to receive the second motor control signal, the second drive motor controller further adapted to control the speed of the second driven wheel in accordance with the second motor control signal.

7. The riding lawn mower of claim 6, the driven wheel controller further adapted to generate the second motor control signal independently of the first motor control signal.

8. A riding lawn mower, comprising:

a fuel combustion engine;

an electrical generator operatively connected to the fuel combustion engine;

a first electric drive motor electrically connected to the electric generator and adapted to propel the riding lawn mower;

a mowing deck adapted to support the cutting blades;

a drive frame adapted to support the drive motor;

a tilting motor attached to the drive section and mechanically coupled to the mowing deck for tilting of the mowing deck;

an operator interface device adapted to generate a tilting signal; and

a tilting motor controller adapted to control the operation of the tilting motor in accordance with the tilting signal.

9. The riding lawn mower of claim 8, further comprising:

a chain/sprocket drive attached to the tilting motor and the mowing deck and adapted to mechanically couple the tilting motor to the mowing deck.

10. The riding lawn mower of claim 8, wherein the tilting motor is only operable when the cutting blades are not energized.

11. A riding lawn mower, comprising:

a drive motor controller adapted to operate a drive motor in accordance with a drive enable signal and generate a speed signal during operation of the drive motor;

a tilting motor controller adapted to operate a tilt motor in accordance with a tilt enable signal and detect a mowing deck in a tilted position and generate a deck tilted signal; and

a master controller adapted to receive the speed signal and the deck tilted signal and selectively enable the drive motor controller by generating the drive enable signal in the absence of the deck tilted signal, and selectively enable the tilting motor controller by generating the tilt enable signal in the absence of the speed signal.

12. A riding lawn mower, comprising:

a blade motor controller adapted to operate a blade motor in accordance with a blade enable signal and generate a blade inhibit signal during operation of the blade motor;

a tilting motor controller adapted to detect a mowing deck in a tilted position and generate a deck tilted signal; and

a master controller adapted to receive the blade inhibit signal and the deck tilted signal and selectively enable the blade motor controller in the absence of the deck tilted signal and selectively enable the tilting motor controller in the absence of the blade inhibit signal.

13. A riding lawn mower, comprising:

a drive motor operated in accordance with a drive enable signal, the drive motor coupled to at least one drive wheel;

a blade motor operated in accordance with a blade enable signal, the blade motor coupled to a cutting blade;

a master controller adapted to control and co-ordinate the drive motor and the blade motor by generating the drive enable signal and a blade enable signal; and

an inverter integrated into the master controller, said inverter operated in accordance with an inverter enable signal, wherein the master controller is further adapted to control and co-ordinate the inverter by generating the inverter enable signal.

14. A riding lawn mower, comprising:

a drive motor operated in accordance with a drive enable signal, the drive motor coupled to at least one drive wheel;

a blade motor operated in accordance with a blade enable signal, the blade motor coupled to a cutting blade;

a master controller adapted to control and co-ordinate the drive motor and the blade motor by generating the drive enable signal and a blade enable signal; and

an inverter operated in accordance with an inverter enable signal, wherein the master controller is further adapted to control and co-ordinate the inverter by generating the inverter enable signal.

15. A riding lawn mower, comprising:

a drive motor operated in accordance with a drive enable signal, the drive motors coupled to at least one drive wheel;

a blade motor operated in accordance with a blade enable signal, the blade motor coupled to a cutting blade;

a master controller adapted to control and co-ordinate the drive motor and the blade motor by generating the drive enable signal and a blade enable signal; and

a tilt motor operated in accordance with a tilt enable signal, wherein the master controller is further adapted to control and co-ordinate the tilt motor by generating the tilt enable signal.

16. An electric riding mower, comprising:

a generator section including an electric generator mechanically driven by an internal combustion engine, the electric generator adapted to generate electrical power;

a drive section including an electric drive motor driving a wheel;

a mowing section including an electric motor driving a cutting blade;

a power output to standard electric utility low voltage AC outlet plugs; and

an inverter electrically connected to the electrical generator and adapted to convert the electrical power to said power output.

17. An electric riding mower, comprising:

a generator section including an electric generator mechanically driven by an internal combustion engine, the electric generator adapted to generate electrical power;

a drive section including an electric drive motor driving a wheel;

a mowing section including an electric motor driving a cutting blade; and

a tilting motor attached to the drive section and mechanically coupled to the mowing section, the tilting motor adapted to raise and lower the mowing section.

18. An electric riding mower, comprising:

a generator section including an electric generator mechanically driven by an internal combustion engine, the electric generator adapted to generate electrical power;

a drive section including an electric drive motor driving a wheel;

a mowing section including an electric motor driving a cutting blade; and

a generator controller adapted to control the output of the generator as an integral part of the mower or as a stand-alone power source.

19. An electric riding mower control system, comprising:

an operator interface device adapted to generate a speed input signal;

a generator controller adapted to control the output of a generator;

a first drive wheel controller adapted to control the speed and torque of a first drive motor;

a tilting drive controller adapted to control the speed and torque of a tilting motor;

a cutting blade controller adapted to control the speed and torque of a blade motor;

a master controller adapted to communicate with each of the controllers for the motors and process the data necessary to co-ordinate the operation of the motors.

20. The electric riding mower control system of claim 19, further comprising:

a second drive wheel controller adapted to control the speed and torque of a second drive motor;

wherein the master controller is adapted to provide independent control of each wheel drive controller to allow the mower to make zero radius turns.