Valvetrain for an internal combustion engine, in particular of a motor vehicle

Patent metadata

Field	Value
Publication number	US-11073052-B2
Application number	US-201816955226-A
Country	US
Kind code	B2
Filing date	Dec 17, 2018
Priority date	Dec 21, 2017
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A valvetrain for an internal combustion engine has a camshaft rotatable about an axis of rotation, a sliding-block element connected in a rotationally fixed manner to the camshaft and displaceable in the axial direction of the camshaft relative thereto, which sliding-block element has an outer circumferential jacket surface with a shift gate via which a rotational movement of the sliding-block element can be converted into a displacement of the sliding-block element in the axial direction of the camshaft relative thereto, and a shift rod at least partially accommodated in the camshaft and displaceable by the sliding-block element in the axial direction of the camshaft relative thereto and via which shift rod an actuation of a gas exchange valve can be influenced.

First claim

The invention claimed is:

1. A valvetrain ( 10 ) of an internal combustion engine, comprising:
a camshaft ( 12 ) rotatable about an axis of rotation ( 14 );
a sliding-block element ( 16 ) connected in a rotationally fixed manner to the camshaft ( 12 ) and displaceable in an axial direction of the camshaft ( 12 ) relative to the camshaft, wherein the sliding-block element has an outer circumferential jacket surface ( 20 ) with a shift gate ( 22 ) via which a rotational movement of the sliding-block element ( 16 ) is convertible into a displacement of the sliding-block element ( 16 ) in the axial direction of the camshaft relative to the camshaft;
a shift rod ( 24 ) at least partially accommodated in the camshaft ( 12 ) and displaceable via the sliding-block element ( 16 ) in the axial direction of the camshaft ( 12 ) relative to the camshaft, wherein an actuation of a gas exchange valve is influenceable by the shift rod;
a bushing ( 26 ), wherein a length region ( 38 ) of the sliding-block element ( 16 ) rotatable about the axis of rotation ( 14 ) relative to the bushing ( 26 ) is accommodated in the bushing ( 26 ) and wherein the bushing ( 26 ) is displaceable in the axial direction of the camshaft ( 12 ) relative to the camshaft;
a form-fitting element ( 50 ) disposed on the bushing ( 26 ) and engaging in a slide region ( 42 ) of the shift gate ( 22 ) which is at least partially arranged in the length region ( 38 ); and
a fixing device ( 54 ) which is switchable between an enabled state as a first state in which the fixing device ( 54 ) enables the displaceability of the bushing ( 26 ) relative to the camshaft ( 12 ) and a fixed state as a second state in which the displaceability of the bushing ( 26 ) in the axial direction of the camshaft ( 12 ) relative to the camshaft is suppressed by the fixing device ( 54 );
wherein the form-fitting element ( 50 ) moves along the slide region ( 42 ) upon a relative rotation between the sliding-block element ( 16 ) and the bushing ( 26 ) and, as a result of a switch-over of the fixing device ( 54 ) from one of the first and second states into the other of the first and second states with form-fitting interaction with the slide region ( 42 ), effects a displacement of the sliding-block element ( 16 ) in the axial direction of the camshaft ( 12 ) relative to the camshaft.

2. The valvetrain ( 10 ) according to claim 1 , wherein the fixing device ( 54 ) has a magnet for providing a magnetic force via which the displaceability of the bushing ( 26 ) in the fixed state is suppressed.

3. The valvetrain ( 10 ) according to claim 1 further comprising a plurality of form-fitting elements ( 50 , 52 ).

4. The valvetrain ( 10 ) according to claim 1 further comprising a spring element ( 72 ) disposed in the camshaft ( 12 ) via which the shift rod ( 24 ) is braceable on the camshaft ( 12 ) in the axial direction of the camshaft ( 12 ).

5. The valvetrain ( 10 ) according to claim 1 further comprising a spring ( 60 ) via which the bushing ( 26 ) is displaceable in the axial direction of the camshaft ( 12 ) relative to the camshaft in a direction of the fixing device ( 54 ).

6. The valvetrain ( 10 ) according to claim 1 further comprising:
a second bushing ( 28 ), wherein a second length region ( 40 ) of the sliding-block element ( 16 ) rotatable about the axis of rotation ( 14 ) relative to the first and second bushings ( 26 , 28 ) is accommodated in the second bushing ( 28 ); and
a second form-fitting element ( 52 ) which is disposed on the second bushing ( 28 ) and engages in a second slide region ( 46 ) of the shift gate ( 22 ) that is at least partially disposed in the second length region ( 40 ).

7. The valvetrain ( 10 ) according to claim 6 further comprising a plurality of second form-fitting elements ( 52 ).

8. The valvetrain ( 10 ) according to claim 6 , wherein, in the enabled state, one of the bushings ( 26 , 28 ) is displaceable in the axial direction of the camshaft ( 12 ) relative to the camshaft and wherein, both in the enabled state and in the fixed state, the other of the bushings ( 26 , 28 ) is fixed in the axial direction of the camshaft ( 12 ) relative to the camshaft.

9. The valvetrain ( 10 ) according to claim 6 , wherein in the enabled state both of the bushings ( 26 , 28 ) are displaceable in the axial direction of the camshaft ( 12 ) relative to the camshaft.

10. The valvetrain ( 10 ) according to claim 6 , wherein at least a part of the fixing device ( 54 ) is disposed in the axial direction of the camshaft ( 12 ) between the bushings ( 26 , 28 ).

Assignees

• Daimler Ag

Inventors

• Mehring Martin

Classifications

• F01L1/053

  overhead type · CPC title

• F01L2013/101

  Electromagnets · CPC title

• F01L33/00

  Rotary or oscillatory slide valve-gear or valve arrangements, specially adapted for machines or engines with variable fluid distribution (drive, adjustment during operation, tripping-gear, reversing-gear, use of working pistons or piston-rods as valves or as valve-supporting elements, valve-gear or valve arrangements peculiar to free-piston machines or engines F01L15/00 - F01L31/00) · CPC title

• F01L1/047

  Camshafts · CPC title

• F01L13/06 Primary

  for braking · CPC title