Electric drivetrain system and method having a single speed ratio direct drive

Patent metadata

Field	Value
Publication number	US-9764633-B1
Application number	US-201615071771-A
Country	US
Kind code	B1
Filing date	Mar 16, 2016
Priority date	Mar 16, 2016
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A machine having a series electric drivetrain system includes an engine to provide mechanical energy to an electric generator, the electric generator able to convert the mechanical energy received from the engine into electrical energy, the electric generator including an input shaft extending through the electric generator, a rotor to rotate on the input shaft, and the input shaft is able to rotate an input gear, an idler gear, a pump drive gear, and a rotor gear, a motor to receive the electrical energy and to produce a rotational output, a single speed ratio direct drive to transfer the rotational output of the motor to a torque output to deliver to a drive shaft, and power electronics to control the electrical energy between the electric generator and the motor and to regulate the rotational output of the motor.

First claim

We claim:

1. A machine having a series electric drivetrain system, the machine comprising:
an engine configured to provide mechanical energy to an electric generator;
the electric generator configured to convert the mechanical energy received from the engine into electrical energy, the electric generator comprising an input shaft extending through the electric generator, a rotor configured to be rotatably supported by and about the input shaft, and the input shaft is configured to rotate an input gear, an idler gear, a pump drive gear, and a rotor gear;
a motor configured to receive the electrical energy and to produce a rotational output;
a single speed ratio direct drive configured to transfer the rotational output of the motor to a torque output to deliver to a drive shaft; and
power electronics configured to control the electrical energy between the electric generator and the motor and to regulate the rotational output of the motor.

2. The machine of claim 1 , wherein the electric generator and the motor are positioned between the engine and the single speed ratio direct drive in an area defining a series electric drivetrain space claim that is comparable to a mechanical drivetrain space claim defined by a mechanical drivetrain system, and the series electric drivetrain system is configured to operate in place of the mechanical drivetrain system.

3. The machine of claim 1 , wherein the rotor is positioned on a hollow rotor shaft, the hollow rotor shaft having a first end and a second end.

4. The machine of claim 3 , wherein the first end of the hollow rotor shaft is rotatably supported about the input shaft at the electric generator to engine connection interface and the second end is rotatably supported about the input shaft and connected to the rotor gear.

5. The machine of claim 1 , wherein the electric generator and hydraulic pumps each use speed-up gearing configured to produce an output speed wherein an output speed of the engine is less than the output speed of the electric generator and the hydraulic pumps.

6. The machine of claim 5 , wherein the input gear drives the idler gear and the idler gear drives the pump drive gear to create a first speed up ratio; and
the idler gear is connected to and rotates in unison with a driven gear, the driven gear drives the rotor gear to create a second speed up ratio.

7. The machine of claim 6 , wherein the series electric drivetrain system using the single speed ratio direct drive is configured to provide a stall torque and run out performance that is consistent with a mechanical drivetrain system using a multispeed transmission.

8. A machine comprising:
an engine configured to provide mechanical energy to an electric generator;
the electric generator configured to convert the mechanical energy received from the engine into electrical energy and into hydraulic power, and the electric generator comprising an input shaft extending through the electric generator, a rotor configured to rotate on the input shaft, and the input shaft is configured to rotate an input gear, an idler gear, a pump drive gear, and a rotor gear;
a motor configured to receive the electrical energy and to produce a rotational output;
a single speed ratio direct drive configured to transfer the rotational output of the motor to a torque output to deliver to a drive shaft; and
power electronics configured to transmit the electrical energy between the electric generator and the motor and to regulate the rotational output of the motor.

9. The machine of claim 8 , wherein the electric generator and the motor are positioned between the engine and the single speed ratio direct drive in an area defining a series electric drive space claim that is comparable to a mechanical drivetrain space claim defined by a mechanical drivetrain system, and a series electric drivetrain system comprising the engine, the electric generator, the motor, and the single speed ratio direct drive is configured to operate in place of the mechanical drivetrain system.

10. The machine of claim 8 , wherein the rotor is positioned on a hollow rotor shaft, the hollow rotor shaft having a first end and a second end.

11. The machine of claim 10 , wherein the first end of the hollow rotor shaft is rotatably supported about the input shaft at the electric generator to engine connection interface and the second end is rotatably supported about the input shaft and connected to the rotor gear.

12. The machine of claim 9 , wherein the electric generator and hydraulic pumps each use speed-up gearing configured to produce an output speed wherein an output speed of the engine is less than the output speed of the electric generator and the hydraulic pumps.

13. The machine of claim 12 , wherein the input gear drives the idler gear and the idler gear drives the pump drive gear to create a first speed up ratio; and
the idler gear is connected to and rotates in unison with a driven gear, the driven gear drives the rotor gear to create a second speed up ratio.

14. The machine of claim 13 wherein the series electric drivetrain system using the single speed ratio direct drive is configured to provide a torque and run out performance that is consistent with a mechanical drivetrain system using a multispeed transmission.

15. A method of replacing a mechanical drivetrain system with a series electric drivetrain system, the method comprising:
removing mechanical components from the mechanical drivetrain system; and
replacing the mechanical components of the mechanical drivetrain system with power electronics and with electrical components of the series electric drivetrain system, wherein:
the electrical components of the series electric drivetrain system comprise a switched reluctance motor and an electric generator with an input shaft extending through the electric generator, the electrical components positioned between an engine and a single speed ratio direct drive in an area defining a series electric drive space claim that is comparable to a mechanical drivetrain space claim defined by the mechanical drivetrain system.

16. The method of claim 15 , wherein removing the mechanical components of the mechanical drivetrain system comprises removing a torque converter, a multispeed transmission, and a drive shaft.

17. The method of claim 16 , wherein replacing the multispeed transmission further comprises replacing the multispeed transmission with the switched reluctance motor, wherein the single speed ratio direct drive is configured to transfer a rotational output of the switched reluctance motor to a torque output to ground engaging members.

18. The method of claim 17 , wherein a stall torque and run out performance of the series electric drivetrain system is comparable to the mechanical drivetrain system.

19. The method of claim 18 , further comprising driving ground engaging members with the switched reluctance motor and the single speed ratio direct drive to provide a stall torque and run out performance with the series electric drivetrain system that is comparable to the mechanical drivetrain system.

20. The method of claim 15 , wherein the series electric drive space claim has a volume that is comparable to a volume of the mechanical drivetrain space claim.

Assignees

• Caterpillar Inc

Inventors

• Dorothy Joshua
• Adra Rodwan
• Zwilling Edward
• Kauk Corey
• Tigue Joseph

Classifications

• Y10S903/916

  with plurality of drive axles · CPC title

• Y10S903/919

  Stepped shift · CPC title

• B60K6/547

  the transmission being a stepped gearing · CPC title

• B60W20/10

  Controlling the power contribution of each of the prime movers to meet required power demand · CPC title

• B62D65/02

  Joining sub-units or components to, or positioning sub-units or components with respect to, body shell or other sub-units or components · CPC title