Positional control of actuator shaft for e-phaser and method of calibration

Patent metadata

Field	Value
Publication number	US-9982572-B2
Application number	US-201414902625-A
Country	US
Kind code	B2
Filing date	Jul 7, 2014
Priority date	Jul 10, 2013
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

An apparatus ( 10 ) and method for controlling an angular position of a camshaft ( 12 ) in an internal combustion engine having a camshaft phaser ( 14 ) for controllably varying the phase relationship between a crankshaft of the internal combustion engine and the camshaft ( 12 ). The camshaft phaser ( 14 ) can be actuated by an electric motor ( 16 ) having an actuator shaft ( 18 ) operating through a gear reduction drive train ( 20 ) having a stationary adjusting member ( 22 ) which rotates when a phase change adjustment is desired. A sensor ( 30 ) can generate a signal corresponding to an angular position of the stationary adjusting member ( 22 ) of the gear reduction drive train ( 20 ). An engine control unit ( 40 ) can adjust a position of the camshaft ( 12 ) through operation of the electric motor ( 16 ) for rotating the stationary adjusting member ( 22 ) based on the generated signal corresponding to the angular position of the stationary adjusting member ( 22 ).

First claim

What is claimed is:

1. A method for controlling an angular position of a camshaft ( 12 ) in an internal combustion engine having a camshaft phaser ( 14 ) for controllably varying a phase relationship between a crankshaft of the internal combustion engine and the camshaft, the camshaft phaser ( 14 ) being actuated by an electric motor ( 16 ) having an actuator shaft ( 18 ) operating through a gear reduction drive train ( 20 ) having a stationary adjusting member ( 22 ) which rotates when a phase change adjustment is desired but is stationary when the phase relationship between the crankshaft and the camshaft is maintained, the method comprising:
generating a signal corresponding to an angular position of the stationary adjusting member ( 22 ) of the gear reduction drive train ( 20 ) with a sensor ( 30 ) that is configured to detect camshaft position prior to engine operation and is positioned with respect to the stationary adjusting member ( 22 ) so that it detects the angular position of the stationary adjusting member ( 22 ); and
adjusting a position of the camshaft ( 12 ) through operation of the electric motor ( 16 ) for rotating the stationary adjusting member ( 22 ) based on the generated signal received from the sensor ( 30 ) corresponding to the angular position of the stationary adjusting member ( 22 ) with an engine control unit ( 40 ).

2. The method of claim 1 , wherein the gear reduction drive train ( 20 ) further comprises:
assembling a planetary gear system ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of planet gears ( 54 ) and having an axis of rotation coaxial with the sun gear ( 52 ) and carrier ( 56 ), wherein the sun gear ( 52 ) defines the stationary adjusting member ( 22 ).

3. The method of claim 1 , wherein the gear reduction drive train ( 20 ) further comprises:
assembling a planetary gear system ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of planet gears ( 54 ) and having an axis of rotation coaxial with the sun gear ( 52 ) and carrier ( 56 ), wherein the carrier ( 56 ) defines the stationary adjusting member ( 22 ).

4. The method of claim 1 , wherein the gear reduction drive train ( 20 ) further comprises:
assembling a planetary gear system ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of planet gears ( 54 ) and having an axis of rotation coaxial with the sun gear ( 52 ) and carrier ( 56 ), wherein the ring gear ( 58 ) defines the stationary adjusting member ( 22 ).

5. The method of claim 1 further comprising:
calibrating ( 500 ) a position of the stationary adjusting member ( 22 ) without running the internal combustion engine including:
moving ( 502 ) the electric motor ( 16 ) to a first stop position;
moving ( 504 ) the electric motor ( 16 ) to a second stop position;
recording ( 506 ) a range of the electric motor movement; and
setting ( 508 ) position sensor ( 30 ) output to first and second direct current voltage values corresponding to the first and second stop positions.

6. The method of claim 1 further comprising:
calibrating ( 600 ) a position of the stationary adjusting member ( 22 ) while running the internal combustion engine including:
receiving ( 602 ) a stationary adjusting member ( 22 ) position sensor ( 30 ) signal;
receiving ( 604 ) a camshaft position sensor ( 32 ) signal;
receiving ( 606 ) a crankshaft position sensor ( 34 ) signal;
determining ( 608 ) if positions are consistent with one another;
if consistent, waiting ( 610 ) for another cam phase adjustment command; and
if not consistent, recalibrating ( 612 ) the stationary adjusting member ( 22 ) position and rechecking position sensor ( 30 , 32 , 34 ) signals for consistency.

7. The method of claim 1 further comprising:
controlling ( 400 ) a position of the stationary adjusting member ( 22 ) including:
determining ( 402 ) a position to command the stationary adjusting member ( 22 ) to move toward in response to a cam phase adjustment signal;
adjusting ( 404 ) the stationary adjusting member ( 22 ) toward the commanded position;
receiving ( 406 ) a stationary adjusting member ( 22 ) position sensor ( 30 ) signal;
determining ( 408 ) if the stationary adjusting member ( 22 ) is in the commanded position;
if not in the commanded position, continuing ( 410 ) movement toward the commanded position; and
if in the commanded position, waiting ( 412 ) for another cam phase adjustment signal.

8. In an apparatus ( 10 ) for controlling an angular position of a camshaft ( 12 ) in an internal combustion engine having a camshaft phaser ( 14 ) for controllably varying a phase relationship between a crankshaft of the internal combustion engine and the camshaft ( 12 ), the camshaft phaser ( 14 ) being actuated by an electric motor ( 16 ) having an actuator shaft ( 18 ) operating through a gear reduction drive train ( 20 ) having a stationary adjusting member ( 22 ) which rotates when a phase change adjustment is desired but is stationary when the phase relationship between the crankshaft and the camshaft is maintained;
a sensor ( 30 ), positioned with respect to the stationary adjusting member ( 22 ) so that it is configured to detect the angular position of the stationary adjusting member ( 22 ) prior to engine operation, generating a signal corresponding to an angular position of the stationary adjusting member ( 22 ) of the gear reduction drive train ( 20 ); and
an engine control unit ( 40 ) for adjusting a position of the camshaft ( 12 ) through operation of the electric motor ( 16 ) for rotating the stationary adjusting member ( 22 ) based on the generated signal received from the sensor ( 30 ) that corresponds to the angular position of the stationary adjusting member ( 22 ).

9. The apparatus ( 10 ) of claim 8 further comprising:
a planetary gear assembly ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of planet gears ( 54 ) and having an axis of rotation coaxial with the sun gear ( 52 ) and carrier ( 56 ), wherein the sun gear ( 52 ) defines the stationary adjusting member ( 22 ).

10. The apparatus ( 10 ) of claim 8 further comprising:
a planetary gear assembly ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of planet gears ( 54 ) and having an axis of rotation coaxial with the sun gear ( 52 ) and carrier ( 56 ), wherein the carrier ( 56 ) defines the stationary adjusting member ( 22 ).

11. The apparatus ( 10 ) of claim 8 further comprising:
a planetary gear assembly ( 50 ) having a sun gear ( 52 ), a plurality of planet gears ( 54 ) rotationally engaging the sun gear ( 52 ) and supported for synchronized rotation about the sun gear ( 52 ) with a carrier ( 56 ), and a ring gear ( 58 ) rotationally engaging the plurality of pl

Assignees

• Borgwarner Inc
• Borgwarner Inc

Inventors

• Simpson Roger T

Classifications

• F01L9/04

  Mechanical Engineering · mapped topic

• F01L2820/042

  Crankshafts position · CPC title

• F01L2800/09

  Calibrating · CPC title

• F01L2013/103

  Electric motors · CPC title

• F01L1/352 Primary

  using bevel or epicyclic gear · CPC title