Patent ID: 9611765
Date: 2017-04-04
CPC Classifications: F01L,F02D

Claim:
1. A method for operating a valve train of an internal combustion engine with a main camshaft and a rotationally-fixed and axially shiftable cam carrier that is associated with a shift gate having at least two sliding slots and an actuator-configured to axially shift the cam carrier between at least two axial positions, wherein each of the sliding slots has a respective ejection ramp in a respective ejection region adapted for radially ejecting the driver out of the actuator out of the respective sliding slot, wherein the respective ejection regions of different sliding slots are located in different rotational angle ranges of the cam carrier, the method comprising: inducing a voltage in the actuator during ejection of the driver from a respective sliding slot; integrating the voltage induced in the actuator over the rotational-angle range associated with each ejection region of a respective sliding slot; associating with each of the different rotational angle ranges a respective threshold value for an expected integrated voltage of the respective rotational angle range; checking for each of the different rotational angle ranges whether the integrated voltage in one of the rotational angle ranges exceeds the respective threshold value; and when the integrated voltage in one of the rotational angle ranges exceeds the given threshold value, generating based on the exceeded threshold value a confirmation signal indicating which of the sliding slots the driver has been ejected from.