Method for mounting a valve train of an internal combustion engine

Patent metadata

Field	Value
Publication number	US-9512742-B2
Application number	US-201414777655-A
Country	US
Kind code	B2
Filing date	Feb 4, 2014
Priority date	Mar 28, 2013
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A method for mounting a valve train ( 1 ) of an internal combustion engine, having, parallel to a row of cam followers ( 2 ), a camshaft ( 13 ) which has a cam ( 15 ) per cam follower ( 2 ), which cam ( 15 ) acts on the roller ( 10 ) of said cam follower ( 2 ), which camshaft ( 13 ) is supported with respect to the cylinder head ( 3 ) via an axial bearing ( 14 ), wherein a) the cam followers ( 2 ) are provided presorted into two main groups (A, B); b) the two mounts ( 11 ) of each cam follower ( 2 ) of the first main group (A) run with offset in relation to the longitudinal extent of the cam follower ( 2 ) in the side surfaces ( 12 ) with respect to one another in such a way that an axial line of the pin ( 9 ) differs in the clockwise direction from perpendicular; c) the offset of the second main group (B) differs in the counterclockwise direction from perpendicular, and d) a partial quantity of the first and second main group (A, B) are selected and mounted for each row of cam followers ( 2 ) in order to minimize/compensate for an axial thrust of the camshaft ( 13 ).

First claim

The invention claimed is:

1. A method for mounting a valve train of an internal combustion engine that is provided with at least one row of cam followers of which each is supported on a bottom side on one end by a pivot support relative to a cylinder head of the internal combustion engine and acts on at least one gas exchange valve on the other end and has, on the other side, at least in a middle section, a cut-out in which a roller that runs on a pin sits, wherein said pin is supported in mounts of side surfaces of the cut-out, and parallel to the row of cam followers there is a camshaft that has, for each of the cam followers, a cam or a sliding cam package acting on a respective one of the rollers and the camshaft is supported by an axial bearing relative to the cylinder head of the internal combustion engine, the method comprising:
a) providing the cam followers pre-sorted into two main groups,
b) the two mounts of each of the cam followers of the first main group run relative to each other with offset with respect to a longitudinal extent of the cam follower in the side surfaces such that an axial line of the pin deviated from perpendicular in a clockwise direction,
c) the two mounts of each of the cam followers of the second main group run relative to each other with offset with respect to the longitudinal extent of the cam follower in the side surfaces such that an axial line of the pin deviates from perpendicular in a counterclockwise direction, and
d) for each row of the cam followers, selecting a sub-group from the first and second main groups and mounting the sub-groups of the cam followers to at least one of minimize or compensate for an axial thrust of the camshaft on the axial bearing.

2. The method according to claim 1 , wherein each of the main groups is made from at least two sub-groups grouped with respect to the offsets thereof.

3. The method according to claim 1 , further comprising: producing the mounts for the pins selectively with a corresponding offset with respect to the longitudinal extent of the cam followers.

4. The method according to claim 1 , further comprising:
e) using cam followers of a completely identical batch for the row of cam followers of the valve train,
f) from said batch, after the production of the identical cam followers, a first sub-group of cam followers whose said mounts in the side surfaces have the offset from the perpendicular in the clockwise direction caused by production tolerance, so that these are the cam followers of the main group and
g) from said batch, after the production of the cam followers, measuring and selecting a second sub-group of cam followers whose said mounts in the side surfaces have the offset from the perpendicular in the counterclockwise direction caused by production tolerance, so that these are the cam followers of the main group.

5. The method according to claim 1 , wherein each of the cylinders of the internal combustion engine has exactly two or a multiple of two identically acting ones of the gas exchange valves,
h) for the variant with two identically acting ones of the gas exchange valves for each of the cylinders, loading one of the gas exchange valves by one of the cam followers from the first main group and another one of the gas exchange valves by one of the cam followers from the second main group, and
i) for the variant with the multiple of two identically acting one of the gas exchange valves for each of the cylinders, a same number of the gas exchange valves are contacted by ones of the cam followers from the first and second main group.

6. The method according to claim 1 , wherein a hydraulic or mechanical support element is provided as the pivot support for the cam follower.

7. A valve train of an internal combustion engine comprising a row of cam followers of which each said cam follower is supported on one side on a bottom side on one end by a pivot support relative to a cylinder head of the internal combustion engine and acts on the other end on at least one gas exchange valve and on the other side has at least in a middle section a cut-out in which a roller that runs on a pin sits, wherein said pin is supported in mounts of side surfaces of the cut-out, a camshaft runs parallel to the row of cam followers and the camshaft has for each of the cam followers a cam or a sliding cam package acting on the roller and the camshaft is supported by an axial bearing relative to the cylinder head of the internal combustion engine, the camshaft loads a row of cam followers that act on identically acting ones of the gas exchange valves for each of the cylinders of the internal combustion engine, wherein each of the cylinders has two of the identically acting ones of the gas exchange valves, and for at least one of minimizing or compensating for an axial thrust of the camshaft on the axial bearing,
j) one of the gas exchange valves is loaded by one of the cam followers whose said mounts run relative to each other with an offset with respect to a longitudinal extent of the cam follower in the side surfaces such that an axial line of the pin deviates from perpendicular in a clockwise direction, and
k) the other of the gas exchange valves is loaded by one of the cam followers whose said mounts run relative to each other with an offset with respect to the longitudinal extent of the cam follower in the side surfaces such that an axial line of the pin deviates from perpendicular in a counterclockwise direction, and
l) the deviations from the perpendicular according to j) and k) are at least approximately equal in of magnitude.

Assignees

• Schaeffler Technologies Ag

Inventors

• Christgen Wolfgang
• Schmidt Volker
• Schober Michael

Classifications

• F01L1/185

  Overhead end-pivot rocking arms · CPC title

• F01L1/047 Primary

  Camshafts · CPC title

• F01L2305/00

  Valve arrangements comprising rollers · CPC title

• F01L2303/00

  Manufacturing of components used in valve arrangements · CPC title

• F01L2103/00

  Mechanical Engineering · mapped topic