Valve drive train device

1. A valve drive train device, of an internal combustion engine including a camshaft ( 35 a ) with at least one axially displaceable first cam element ( 11 a , 11 b ) having axially overlapping movable first and second cam element sections ( 11 a , 12 a ; 11 b , 12 b ) provided with a shift gate ( 13 a, 13 b ) for sequentially displacing the first cam element section ( 11 a , 11 b ) and the second cam element section ( 12 a , 12 b ) on the camshaft ( 35 a ), and an actuating device ( 10 a , 10 b ) for displacing the axially displaceable cam element sections ( 11 a , 12 a ; 11 b , 12 b ) by means of the shift gate ( 13 a ; 13 b ) to at least three switching positions, the shift gate ( 13 a ; 13 b ) having at least two gate tracks ( 36 a , 37 a ; 36 b , 37 b ), each including four switch segments ( 14 a - 21 a ; 14 b - 21 b ) and the switch segments being assigned to a gate track ( 36 a , 37 a: 36 b , 37 b ) of a switching direction, the gate tracks ( 36 a , 37 a ; 36 b , 37 b ) extending over a rotational angle in excess of 360° and being arranged in each case partially on the first cam element section ( 11 a ; 11 b ) and partially on the second cam element section ( 12 a , 12 b ).

2. The valve drive train device according to claim 1 , wherein the actuating device ( 10 a ; 10 b ) is provided to switch the at least one axially displaceable cam element to one of a zero lift, a partial lift and a full lift position.

3. The valve drive train device according to claim 1 , wherein in each case two of the switching segments ( 14 a - 21 a ; 14 b - 21 b ) are provided to move the first cam element ( 11 a, 11 b ) in the switching direction and two further switch segments ( 15 a , 17 a , 19 a, 21 a ; 15 b , 17 b , 19 b , 21 b ), are provided for displacing the second cam element ( 12 a , 12 b ) in the switching direction.

4. The valve drive train device according to claim 1 , the switching elements ( 14 a - 21 a , 14 b - 21 b ) are in each case alternatively assigned to the cam elements ( 11 a , 12 a ; 11 b , 12 b ), whereby the shifting gate ( 13 a; 13 b ) is provided for sequentially displacing the first cam element ( 11 a ; 11 b ) and a second cam element ( 12 a ; 12 b ) depending on a rotational position angle of the cam elements ( 11 a , 12 a ; 11 b , 12 b ).

5. The valve drive train device according to claim 1 , wherein the actuating device ( 10 a ; 10 b ) has a reset unit ( 22 a ; 22 b ) which is provided for terminating a switching action immediately after a displacement of the first cam element ( 11 a , 11 b ) or after a displacement of the second cam element ( 12 a, 12 b ) before reaching an end of the shifting gate ( 13 a , 13 b ).

6. The valve drive train device according to at least claim 5 , wherein the reset unit ( 22 a ) has switching units ( 23 a, 24 a ) which include first and second actuators ( 27 a , 28 a ) and the switch elements ( 25 a , 26 a )are movable into a neutral position by means of an actuator ( 27 a , 28 a ), the actuating device ( 10 a ) including a coupling element ( 69 a ) by means of which the first and second switch elements ( 25 a , 26 a ) are coupled for movement together whereby the second switch element is moved by the first actuator ( 27 a ) and the first switch element can be moved by the second actuator ( 28 a ) into the neutral position.

7. The valve drive train device according to at least claim 5 , wherein the shifting gate ( 13 b ) has at least one intermediate segment ( 29 b - 34 b ) with a reset element ( 72 b - 77 b ) in the form of an area raised over a gate path base level ( 78 b ), but is disposed fully within the guide path ( 36 b , 37 b ) and which is provided to terminate the switching action ahead of an end of the shift gate ( 13 b ).

8. The valve drive train device according to claim 4 , wherein between the switch segments ( 14 b - 21 b ) in each case an intermediate segment ( 29 b - 24 b ) is arranged.

9. The valve drive train device according to claim 1 , wherein the actuating device ( 10 a , 10 b ) includes two switching units ( 23 a , 24 a ; 23 b , 24 b ) each with a switching element ( 25 a , 26 a ; 25 b , 26 b ) in the form of a switching pin ( 51 a , 52 a; 51 b , 52 b ) wherein the switching pin ( 51 a , 51 b ) of the first switching unit ( 23 a, 23 b ) is engaged in an extended position in the first gate track ( 36 a , 36 b ) and the switching pin ( 52 a, 52 b) of the second switching unit ( 24 a, 24 b) is engaged in the extended position in the second gate track ( 37 a , 37 b ).