HYBRID EARTHMOVER
A hydraulic hybrid powertrain system for use with an earth mover of the present invention comprises a power plant generating a high pressure fluid at an output including a variable displacement pump and automated throttle control; an energy storage system; and a drive system. The power plant includes an engine driving a hydraulic pump/motor to generate the high pressure fluid. The hydraulic pump is preferably a variable displacement pump and the system includes an automated throttle control. Together these elements maintain the system fluid pressure. A cylinder is provided within the drive system for retarding the amount of the displacement within a displacement pump to maintain system pressure. The energy storage system is an accumulator.
1 . A hydraulic hybrid powertrain system for use with an earth mover comprising:
a power plant generating a high pressure fluid at an output including a variable displacement pump and automated throttle control;
an energy storage system; and
a drive system comprising:
at least one drive motor responsive to said high pressure fluid for generating rotary motion at an output;
a mode selection means connected to said power plant output and said at least one drive motor for selecting a mode of operation from a plurality of modes of operation of said at least one drive motor;
a control means connected to said power plant and said at least one drive motor for controlling operation of an earth mover in said plurality of modes of operation.
2 . The system according to claim 1 wherein said power plant includes an engine driving a hydraulic pump/motor to generate said high pressure fluid, and said variable displacement pump and automated throttle control maintain the system fluid pressure.
3 . The system according to claim 2 wherein said mode selection means includes a cylinder for retarding the amount of the displacement within a displacement pump to maintain system pressure.
4 . The system according to claim 1 wherein said energy storage system is an accumulator.
5 . The system according to claim 3 wherein said energy storage system is an accumulator.
6 . The system according to claim 5 wherein said accumulator supplements the flow of pressurized fluid when said mode selection exceeds said power plant capabilities.
7 . The system according to claim 1 wherein said at least one drive motor is a variable displacement pump/motor and said control means selectively varies a displacement of said pump/motor.
8 . A hydraulic hybrid powertrain system for operating construction equipment comprising:
a power plant generating a high pressure fluid at an output including a closed center system having a variable displacement pump and automated throttle control;
an energy storage system; and
a drive system comprising:
at least one drive motor responsive to said high pressure fluid for generating rotary motion at an output.
9 . The hydraulic hybrid powertrain system of claim 8 further comprising a closed center accessory system linked to said powertrain system.
10 . The system according to claim 8 wherein said power plant includes an engine driving a hydraulic pump/motor to generate said high pressure fluid, and said variable displacement pump and automated throttle control maintain the system fluid pressure.
11 . The system according to claim 10 wherein said drive system includes a cylinder for retarding the amount of the displacement within a displacement pump to maintain system pressure.
12 . The system according to claim 8 wherein said energy storage system is an accumulator.
13 . The system according to claim 11 wherein said energy storage system is an accumulator.
14 . The system according to claim 13 wherein said accumulator supplements the flow of pressurized fluid when said mode selection exceeds said power plant capabilities.
15 . The system according to claim 8 wherein said at least one drive motor is a variable displacement pump/motor and said control means selectively varies a displacement of said pump/motor.
16 . A hydraulic hybrid powertrain system for use with a vehicle comprising:
a power plant generating a high pressure fluid at an output including a variable displacement pump and automated throttle control;
an energy storage system; and
a drive system comprising:
at least one drive motor responsive to said high pressure fluid for generating rotary motion at an output;
a mode selection means connected to said power plant output and said at least one drive motor for selecting a mode of operation from a plurality of modes of operation of said at least one drive motor;
a control means connected to said power plant and said at least one drive motor for controlling operation of an earth mover in said plurality of modes of operation; and
mechanical means for retarding the displacement of said drive motor.
17 . The system according to claim 16 wherein said power plant includes an engine driving a hydraulic pump/motor to generate said high pressure fluid, and said variable displacement pump and automated throttle control maintain the system fluid pressure.
18 . The system according to claim 16 wherein said mechanical means includes a cylinder for retarding the amount of the displacement within a displacement pump to maintain system pressure.
19 . The system according to claim 16 wherein said energy storage system is an accumulator.
20 . The system according to claim 18 wherein said energy storage system is an accumulator.
21 . The system according to claim 19 wherein said accumulator supplements the flow of pressurized fluid when said mode selection exceeds said power plant capabilities.
22 . The system according to claim 16 wherein said at least one drive motor is a variable displacement pump/motor and said control means selectively varies a displacement of said pump/motor.