Patent ID: 8474421

Claim:
A valve train device for an internal combustion engine, with a switching unit ( 11 a , 11 b ) comprising an electric actuator ( 17 a , 17 b ) with a solenoid unit ( 20 a , 20 b ) including a coil ( 21 a , 21 b ) and with a control unit ( 10 a , 10 b ) for monitoring a switching operation of the switching unit ( 11 a , 11 b ) by a switching element ( 18 a ) of the electric actuator ( 17 a , 17 b ) engaging and switching an axially displaceable cam element ( 12 a , 12 b ) by means of a shift gate ( 13 a , 13 b ) formed in the axially displaceable cam element ( 12 a , 12 b ), the control unit ( 10 a , 10 b ) for monitoring the switching unit ( 11 a , 11 h ) taking into account at least one characteristic value for a voltage integral ( 14 a , 14 b ) over a voltage ( 31 a , 31 b ) which is induced in a the coil ( 21 a , 21 b ) of the switching unit ( 11 a , 11 b ) during the switching operation by a disengagement of the switching element ( 18 a ) from the axially displaceable cam element ( 12 a , 12 b ) and to set its value with respect to a characteristic limit value stored in the control unit ( 10 a , 10 b ).