US 12,110,814 B2
Apparatus and method for controlling a cam
YoungMo Lee, Munich (DE); HaMyeong Song, Munich (DE); and JaeWon Choi, Munich (DE)
Assigned to VITESCO TECHNOLOGIES GMBH, Hannover (DE)
Appl. No. 17/420,777
Filed by Vitesco Technologies GmbH, Hannover (DE)
PCT Filed Jan. 2, 2020, PCT No. PCT/EP2020/050008
§ 371(c)(1), (2) Date Jul. 6, 2021,
PCT Pub. No. WO2020/141189, PCT Pub. Date Jul. 9, 2020.
Claims priority of application No. 10-2019-0001337 (KR), filed on Jan. 4, 2019.
Prior Publication US 2022/0065141 A1, Mar. 3, 2022
Int. Cl. F01L 1/344 (2006.01); F01L 13/00 (2006.01); F02D 13/02 (2006.01); F02D 41/24 (2006.01); F02D 41/00 (2006.01); F02D 41/20 (2006.01)
CPC F01L 1/3442 (2013.01) [F01L 13/0015 (2013.01); F02D 13/0215 (2013.01); F02D 41/2464 (2013.01); F01L 2001/34426 (2013.01); F01L 2001/3443 (2013.01); F01L 2001/34433 (2013.01); F01L 2201/00 (2013.01); F01L 2800/00 (2013.01); F01L 2820/041 (2013.01); F02D 2041/001 (2013.01); F02D 2041/2027 (2013.01); F02D 2041/2055 (2013.01); Y02T 10/12 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for controlling a cam using an ECU (electronic control unit), the method comprising:
learning a holding region in which linearity is not ensured by increasing or decreasing a pulse width modulation (PWM) signal while the cam maintains a holding state;
based on the holding region, generating a final PWM signal;
wherein the final PWM signal comprises a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position; and
transmitting the final PWM signal to an oil control valve;
wherein learning the holding region comprises:
increasing the PWM signal if the cam is positioned in a target area;
halting the increase of the PWM signal at an instant in which a position of the cam changes whilst increasing the PWM signal, and storing the PWM signal, the increase of which has been halted, as a holding advance region among a set of engine conditions;
decreasing the PWM signal in the holding advance region;
halting the decrease of the PWM signal at an instant the position of the cam changes whilst decreasing the PWM signal, and storing the PWM signal, the decrease of which has been halted, as a holding retard region among the set of engine conditions; and
defining an average of the PWM signal in the holding advance region and the PWM signal in the holding retard region as a learned value of the holding region.