Kinetic energy system and method for hybrid machine

• US 8,718,889 B2
• Filed: 02/29/2012
• Issued: 05/06/2014
• Est. Priority Date: 02/29/2012
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Jensen, Jeffrey Edward
• Primary Examiner(s): FREJD, RUSSELL WARREN
• Application Number:
  US13/408,391
• Publication Number:
  US 20130226419A1
• Time in Patent Office: 797 Days
• Field of Search: 701/67, 701/68, 701/99, 192/70.11, 192/48.8, 192/70.21, 180/165, 74/11, 746/61
• US Class Current: 701/68
• CPC Class Codes: B60K 6/105 the accumulator being a flywheel
• CPC Class Codes: B60Y 2400/72 Continous variable transmissions [CVT]
• CPC Class Codes: F16H 33/02 Rotary transmissions with mechanical accumulators, e.g. weights, springs, intermittently-connected flywheels
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10T 74/19014 Plural prime movers selectively coupled to common output

Abstract

A kinetic energy system incorporates multiple flywheels, each flywheel situated and adapted to develop and store kinetic energy, and to subsequently impart that energy to move a work machine. Each flywheel is controlled by an ECM to operate in a selective sequence with respect to any of the other flywheels. Each flywheel has its own individual external gear and clutch unit adapted to be in communication with a commonly shared continuously variable transmission. The plurality of flywheels may be operated sequentially to develop, store, and dispense kinetic energy equivalently to that of a substantially larger unitary flywheel. In the disclosed embodiment and method of operation, the flywheel system may be employed with a traditional internal combustion engine to produce a hybrid motive source, with capability for effectively meeting transient load demands of an off-road work machine.

Claims

1. A kinetic energy system, comprising:

a power source,

multiple flywheels, each flywheel having a drive gear and clutch unit;

a transmission selectively driven by the power source, and selectively and operatively connected to each flywheel to drive or be driven by each flywheel; and

a controller communicatively connected to the transmission and each flywheel, and configured to generate signals to selectively connect the power source to the transmission to drive the transmission, and generate signals to selectively and sequentially connect the transmission to each of the flywheels.

2. The kinetic energy system of claim 1, wherein the controller is configured to store kinetic energy from drivetrain energy during downhill descents of the work machine, and to subsequently dispense the drivetrain energy directly into an internal combustion engine of the work machine.

3. The kinetic energy system of claim 1, further comprising a power take-off operatively connected to the transmission to be selectively driven by the transmission.

4. The kinetic energy system of claim 1, wherein the clutch unit of each flywheel comprises a clutch pack interposed between that flywheel and its associated flywheel drive gear.

5. The kinetic energy system of claim 4, wherein the clutch pack and associated drive gear of each flywheel are physically interposed between the transmission and the flywheel.

6. The kinetic energy system of claim 1, wherein the transmission is a continuously variable transmission, and wherein the flywheels are supported circumferentially with respect to one another on a common support member about the continuously variable transmission.

7. The kinetic energy system of claim 6, wherein the support member is ring-shaped.

8. The kinetic energy system of claim 1, wherein each flywheel is situated in an individual vacuum housing.

9. The kinetic energy system of claim 1, wherein each flywheel is situated in a single shared vacuum housing.

10. A kinetic energy system for a hybrid work machine, comprising:

a power source;

a flywheel system comprising multiple flywheels, each having a drive gear and clutch unit;

a transmission selectively driven by the power source, and selectively and operatively connected to each flywheel to drive or be driven by each flywheel; and

a controller communicatively connected to the transmission and each flywheel, and configured to generate signals to selectively connect the power source to the transmission to drive the transmission, and generate signals to selectively and sequentially connect the transmission to each of the flywheels.

11. The kinetic energy system of claim 10, wherein the controller is configured to store mechanical energy from drivetrain energy during downhill descents of the work machine, and to subsequently dispense the drivetrain energy directly to an internal combustion engine of the work machine.

12. The kinetic energy system of claim 10, further comprising a power take-off operatively connected to the transmission to be selectively driven by the transmission.

13. The kinetic energy system of claim 10, wherein the clutch unit of each flywheel comprises a clutch pack interposed between that flywheel and its associated flywheel drive gear.

14. The kinetic energy system of claim 13, wherein the clutch pack and associated drive gear of each flywheel are physically interposed between the transmission and the flywheel.

15. The kinetic energy system of claim 10, wherein the transmission is a continuously variable transmission, and wherein the flywheels are supported circumferentially with respect to one another on a common support member about the continuously variable transmission.

16. The kinetic energy system of claim 15, wherein the support member is ring-shaped.

17. The kinetic energy system of claim 10, wherein each flywheel is situated in an individual vacuum housing.

18. The kinetic energy system of claim 10, wherein each flywheel is situated in a single shared vacuum housing.

19. A method of using a kinetic energy system, comprising the steps of:

providing multiple flywheels in a work machine, with each flywheel having a drive gear;

providing a CVT with a gear in engagement with each of the flywheel drive gears;

providing a system of individual flywheel clutch packs, each clutch pack situated between a flywheel gear and associated flywheel to engage and control rotation of that one flywheel;

providing an ECM to monitor and control the CVT to simultaneously and individually control each flywheel clutch pack so as to enable the CVT to sequentially engage each clutch pack to develop kinetic energy sequentially in each flywheel; and

the ECM subsequently controlling the CVT and each flywheel clutch pack to transfer kinetic energy sequentially from each flywheel to provide motive power to the work machine during transient periods of power demand.

22. The method of claim 19, further comprising the steps of:

providing a vacuum housing about each flywheel;

providing a vacuum pump and vacuum lines between the vacuum housings and the pump to support and maintain a vacuum within each of the housings.

20. A method of recovering stored kinetic energy in a machine having work functions, comprising:

selectively driving a transmission with a first flywheel;

selectively driving the transmission with a second flywheel;

selectively driving the output of a power source with the transmission to augment the power source and increase power available for the work functions.

21. A method of storing kinetic energy in a machine having work functions, comprising:

selectively driving a transmission with a power source when the power source produces greater power than needed for the work functions;

selectively driving a first flywheel with the transmission; and

selectively driving a second flywheel with the transmission.