Linear actuator
View Patent ↗A linear actuator for driving an actuating element of an internal combustion engine of a motor vehicle has two scanning elements for scanning opposite sides of a guide cam. The guide cam has a protruding rib against which the two scanning elements are pre-tensioned to permit a play-free scan of the guide cam.
1. A linear actuator ( 8 ) for driving an actuator element ( 4 ) for an internal combustion engine of a motor vehicle, comprising:
a rotatable drive shaft ( 12 );
an axially displaceable ram ( 11 ) configured to adjust the actuator element ( 4 );
a guide curve ( 16 ) driven by the rotatable drive shaft ( 12 ); and
a guide member ( 18 ) configured to scan the guide curve ( 16 ), the guide member ( 18 ) comprising:
(a) a bow-shaped spring plate ( 23 ),
(b) a first scanning body ( 19 ) arranged at an upper end of the bow-shaped spring plate ( 23 ) of the guide member ( 18 ), and
(c) a second scanning body ( 20 ) arranged at a lower end of the bow-shaped spring plate ( 23 ) of the guide member ( 18 ), the first and second scanning bodies ( 19 , 20 ) of the guide member ( 18 ) being pretensioned against opposite sides of the guide curve ( 16 ) by the bow-shaped spring plate ( 23 ) of the guide member ( 18 ),
wherein the ram ( 11 ) is connected to the lower end of the bow-shaped spring plate ( 23 ) of the guide member ( 18 ), the ram ( 11 ) being driven axially, to adjust the actuator element ( 4 ), by the guide member ( 18 ) based upon axial movement produced by interaction between the first and second scanning bodies ( 19 , 20 ) of the guide member ( 18 ) and the guide curve ( 16 ).
2. The linear actuator as claimed in claim 1 , wherein the guide curve ( 16 ) has a protruding rib ( 17 ) and the first and second scanning bodies ( 19 , 20 ) of the guide member ( 18 ) lie against opposite sides of the rib ( 17 ).
3. The linear actuator as claimed in claim 1 , wherein contact points of the first and second scanning bodies ( 19 , 20 ) of the guide member ( 18 ) on the guide curve ( 16 ) are arranged so as to be aligned with a rotational axis of the ram ( 11 ).
4. The linear actuator as claimed in claim 1 , wherein the first and second scanning bodies ( 19 , 20 ) of the guide member ( 18 ) each comprise a roller bearing ( 21 , 22 ).
5. The linear actuator as claimed in claim 1 , further comprising:
a disc ( 14 ) extending over a partial circle; and
a pinion ( 13 ), driven by the drive shaft ( 12 ),
wherein the guide curve ( 16 ) is arranged on the disc ( 14 ), the disc ( 14 ), on its periphery, has a partial toothed rim ( 15 ), and the pinion ( 13 ) intermeshes with the partial toothed rim ( 15 ) of the disc ( 14 ).
6. The linear actuator as claimed in claim 5 , further comprising a fixed stop ( 9 ) protruding into a movement region of the disc ( 14 ).
7. The linear actuator as claimed in claim 1 , further comprising a valve body ( 5 ) connected to the ram ( 11 ), the valve body ( 5 ) comprising a second stop ( 10 ).