Engine balance assembly using electric motors

Patent metadata

Field	Value
Publication number	US-10100900-B2
Application number	US-201715429072-A
Country	US
Kind code	B2
Filing date	Feb 9, 2017
Priority date	Feb 18, 2016
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A balance assembly for an engine is provided. The balance assembly includes a first electric motor coupled to the engine and configured to rotate a first eccentric mass relative to the engine, the first eccentric mass being coupled to a first shaft of the first electric motor, and a second electric motor coupled to the engine and configured to rotate a second eccentric mass relative to the engine, the second eccentric mass being coupled to a second shaft of the second electric motor. The first and second electric motors are configured to rotate the first and second eccentric masses in order to balance a vibration characteristic of the engine.

First claim

The invention claimed is:

1. A balance assembly for an engine, comprising:
a first electric motor coupled to the engine and configured to rotate a first eccentric mass relative to the engine, the first eccentric mass being coupled to a first shaft of the first electric motor; and
a second electric motor coupled to the engine and configured to rotate a second eccentric mass relative to the engine, the second eccentric mass being coupled to a second shaft of the second electric motor;
wherein the first and second electric motors are configured to rotate the first and second eccentric masses in order to balance a vibration characteristic of the engine; and
wherein the first and second electric motors are provided on opposite longitudinal ends of the engine to each other.

2. The balance assembly according to claim 1 , wherein the first electric motor comprises a first rotary encoder configured to determine a phase angle of the first shaft of the first electric motor and the second electric motor comprises a second rotary encoder configured to determine a phase angle of the second shaft of the second electric motor.

3. The balance assembly according to claim 1 , further comprising a controller configured to determine a difference in phase angle of the first and/or second shafts relative to a crank shaft of the engine.

4. The balance assembly according to claim 3 , wherein the controller is configured to maintain differences in phase angles between the first and/or second shafts and the crank shaft of the engine, the differences in phase angles being equal to predetermined values.

5. The balance assembly according to claim 3 , wherein the controller is configured to maintain a predetermined difference in phase angle between the first and second shafts.

6. The balance assembly according to claim 3 , wherein the controller is configured to maintain a difference in phase angle of 180 degrees between the first and second shafts.

7. The balance assembly according to claim 1 , further comprising a controller configured to adjust a difference in phase angle between the first and second shafts and/or a crank shaft of the engine according to a variation in valve timing of the engine.

8. The balance assembly according to claim 1 , further comprising a controller configured to adjust a difference in phase angle between the first and second shafts and/or a crank shaft of the engine following a cylinder deactivation or activation event of the engine.

9. The balance assembly according to claim 1 , wherein the first and second electric motors are configured to rotate at speeds equal to a rotational speed of a crank shaft of the engine.

10. The balance assembly according to claim 1 , wherein the first and second electric motors are configured to rotate at speeds equal to twice a rotational speed of a crank shaft of the engine.

11. The balance assembly according to claim 1 , wherein the first and/or second electric motors are provided within cavities defined by one or more housings of the engine.

12. The balance assembly according to claim 1 , wherein the first and second electric motors are configured to rotate the first and second eccentric masses respectively, responsive to the engine operating above a threshold running speed.

13. The balance assembly according to claim 1 , wherein the balance assembly further comprises:
a third electric motor coupled to the engine and configured to rotate a third eccentric mass relative to the engine, the third eccentric mass being coupled to a third shaft of the third electric motor; and
a fourth electric motor coupled to the engine and configured to rotate a fourth eccentric mass relative to the engine, the fourth eccentric mass being coupled to a fourth shaft of the fourth electric motor;
wherein the third and fourth electric motors are configured to rotate the third and fourth eccentric masses in a direction opposite to a direction of rotation of the first and second electric motors.

14. The balance assembly according to claim 13 , wherein:
the third and fourth electric motors are provided such that the third and fourth shafts are axially aligned;
the third and fourth electric motors are offset from the first and/or second shafts; and
the third and fourth electric motors are configured to rotate at speeds equal to twice a rotational speed of a crank shaft of the engine.

15. A method of balancing vibrations of an Internal Combustion Engine (ICE) assembly, the ICE assembly comprising an ICE and a balance assembly, the balance assembly comprising:
a first electric motor coupled to the ICE and configured to rotate a first eccentric mass relative to the ICE, the first eccentric mass being coupled to a first shaft of the first electric motor; and
a second electric motor coupled to the ICE and configured to rotate a second eccentric mass relative to the ICE, the second eccentric mass being coupled to a second shaft of the second electric motor; and wherein the first and second electric motors are provided on opposite longitudinal ends of the ICE to each other, the method comprising:
driving the first and second motors to rotate the first and second eccentric masses to balance a vibration characteristic of the ICE.

16. The method according to claim 15 , wherein the method further comprises:
determining a running speed of the ICE; and
wherein driving the first and second electric motors comprises driving the first and second electric motors only when the ICE is running at a speed above a threshold value.

17. The method according to claim 15 , wherein the method further comprises:
identifying a variation in valve timing of the ICE; and
responsive to the identification, controlling operation of the first and/or second electric motors to adjust a difference in phase angle between the first and/or second shafts and/or a crank shaft of the ICE.

18. The method according to claims 15 , wherein the method further comprises:
identifying a cylinder deactivation or reactivation of the ICE; and
responsive to the identification, controlling operation of the first and/or second electric motors to adjust a difference in phase angle between the first and/or second shafts and/or a crank shaft of the ICE.

19. The method according to claim 15 , wherein the method further comprises:
identifying a cylinder deactivation or reactivation of the ICE; and
responsive to the identification, controlling operation of the first and/or second electric motors to adjust a speed of rotation of the first and/or second eccentric masses.

20. A method, comprising:
activating a first electric motor and a second electric motor responsive to engine speed exceeding a threshold speed, the first electric motor rotating a first eccentric mass positioned on a first end of an engine, the second electric motor rotating a second eccentric mass positioned on a second end of the engine; and
adjusting one or more parameters of the first electric motor responsive to a change in engine operation.

Assignees

• Ford Global Tech Llc

Inventors

• Gregory Jonathan
• Scoging Neill
• Caine Jon Edward
• Haeuser Viktor
• Rogers Ivan Mark

Classifications

• F16F15/22 Primary

  Compensation of inertia forces {(suppression of vibrations of rotating systems by favourable grouping or relative arrangements of the moving members of the system or systems F16F15/20, counterweights F16F15/28; correcting-weights for balancing rotating bodies F16F15/32)} · CPC title

• F02B75/06 Primary

  Engines with means for equalising torque · CPC title

• F16F15/322

  the rotating body being a shaft (F16F15/34, F16F15/36 take precedence) · CPC title

• F02D29/00

  Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto · CPC title

• F16F15/32 Primary

  Correcting- or balancing-weights or equivalent means for balancing rotating bodies, e.g. vehicle wheels {(suppression of vibrations in rotating systems by using freely rotating masses F16F15/14; compensation of inertia forces F16F15/22; compensating imbalance for testing purposes G01M1/30)} · CPC title