U.S. patent application number 17/161659 was filed with the patent office on 2021-07-29 for camshaft assembly.
This patent application is currently assigned to Mahle International GmbH. The applicant listed for this patent is Christoph Steinmetz, Frau M. Turrek. Invention is credited to Christoph Steinmetz, Frau M. Turrek.
Application Number | 20210231031 17/161659 |
Document ID | / |
Family ID | 1000005510220 |
Filed Date | 2021-07-29 |
United States Patent
Application |
20210231031 |
Kind Code |
A1 |
Turrek; Frau M. ; et
al. |
July 29, 2021 |
CAMSHAFT ASSEMBLY
Abstract
A camshaft assembly for an internal combustion engine of a motor
vehicle is disclosed. The camshaft assembly includes a camshaft
extending along an axial direction and at least one cam
non-rotatably arranged on the camshaft. An axial bearing is
provided for at least one of an axial alignment and an axial fixing
of the camshaft. The at least one cam is part of the axial
bearing.
Inventors: |
Turrek; Frau M.;
(Weinstadt-Beutelsbach, DE) ; Steinmetz; Christoph;
(Ludwigsburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Turrek; Frau M.
Steinmetz; Christoph |
Weinstadt-Beutelsbach
Ludwigsburg |
|
DE
DE |
|
|
Assignee: |
Mahle International GmbH
|
Family ID: |
1000005510220 |
Appl. No.: |
17/161659 |
Filed: |
January 28, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01L 2001/0476 20130101;
F01L 1/047 20130101 |
International
Class: |
F01L 1/047 20060101
F01L001/047 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 29, 2020 |
DE |
102020201038.2 |
Claims
1. A camshaft assembly, comprising: a camshaft extending along an
axial direction and at least one cam non-rotatably arranged on the
camshaft, an axial bearing for at least one of an axial alignment
and an axial fixing of the camshaft, wherein the at least one cam
is part of the axial bearing.
2. The assembly according to claim 1, wherein the axial bearing
includes a first axial bearing element and a second axial bearing
element that lie opposite one another along the axial direction,
and wherein the at least one cam is arranged axially between the
first axial bearing element and the second axial bearing element so
that the camshaft with the at least one cam can rotate relative to
the first bearing element and the second bearing element about a
centre longitudinal axis of the camshaft running in the axial
direction.
3. The assembly according to claim 2, wherein the at least one cam
is clamped between the first bearing element and the second bearing
element so as to be rotatably adjustable about the centre
longitudinal axis of the camshaft.
4. The assembly according to claim 1, wherein the axial bearing
includes a first cam and a second cam non-rotatably arranged on the
camshaft spaced apart from one another, and a first axial bearing
element and a second axial bearing element arranged relative to one
another on or at the camshaft such that the first bearing element
and the first cam limit a movement of the camshaft in the axial
direction and the second bearing element and the second cam limit
an axial movement of the camshaft against the axial direction.
5. The assembly according to claim 4, wherein the first bearing
element and the second bearing element are arranged between the
first cam and the second cam along the axial direction.
6. The assembly according to claim 4, wherein the first cam and the
second cam are arranged between the first bearing element and the
second bearing element along the axial direction.
7. The assembly according to claim 2, wherein two axial end faces
of the at least one cam facing the first bearing element and the
second bearing element and two end faces of the first bearing
element and the second bearing element facing the at least one cam
each form sliding surfaces of the axial bearing.
8. The assembly according to claim 2, wherein the first bearing
element and the second bearing element are structured for absorbing
axial forces.
9. The assembly according to claim 2, wherein the axial bearing
consists of the at least one cam and the first bearing element and
the second bearing element.
10. An internal combustion engine, comprising: at least one
cylinder block that comprises a combustion chamber and at least one
adjustable valve for introducing fresh air into the combustion
chamber or for discharging exhaust gas out of the combustion
chamber, a camshaft assembly, the camshaft assembly including: a
camshaft extending along an axial direction and at least one cam
non-rotatably arranged on the camshaft, an axial bearing for at
least one of an axial alignment and an axial fixing of the
camshaft, wherein the at least one cam is part of the axial
bearing, wherein the axial bearing includes a first axial bearing
element and a second axial bearing element that lie opposite one
another along the axial direction, and wherein the at least one cam
is arranged axially between the first axial bearing element and the
second axial bearing element such that the camshaft with the at
least one cam can rotate relative to the first axial bearing
element and the second axial bearing element about a centre
longitudinal axis of the camshaft running in the axial direction,
wherein the first bearing element and the second bearing element
are arranged fixed in place relative to the at least one cylinder
block, and wherein the at least one cam of the axial bearing is
drive-connected to the at least one valve for adjusting the at
least one valve.
11. The internal combustion engine according to claim 10, wherein
the camshaft is rotatably mounted on the at least one cylinder
block via a radial bearing.
12. The internal combustion engine according to claim 10, wherein
the at least one cam is clamped between the first axial bearing
element and the second axial bearing element so as to be rotatably
adjustable about the centre longitudinal axis of the camshaft.
13. The internal combustion engine according to claim 10, wherein
the axial bearing further includes a first cam and a second cam
non-rotatably arranged on the camshaft spaced apart from one
another, and wherein the first cam and the first bearing element
are structured and arranged to limit a first axial movement of the
camshaft in the axial direction, and the second cam and the second
bearing element are structured and arranged to limit a second axial
movement of the camshaft against the axial direction.
14. The internal combustion engine according to claim 13, wherein
the first bearing element and the second bearing element are
arranged between the first cam and the second cam along the axial
direction.
15. The internal combustion engine according to claim 13, wherein
the first cam and the second cam are arranged between the first
bearing element and the second bearing element along the axial
direction.
16. The internal combustion engine according to claim 13, wherein
two axial end faces of the at least one cam that face the first
bearing element and the second bearing element and two end faces of
the first bearing element and the second bearing element that face
the at least one cam form sliding surfaces of the axial
bearing.
17. The internal combustion engine according to claim 13, wherein
the first bearing element and the second bearing element are
structured for absorbing axial forces.
18. The internal combustion engine according to claim 10, wherein
the axial bearing consists of the at least one cam and the first
bearing element and the second bearing element.
19. The internal combustion engine according to claim 10, wherein
two axial end faces of the at least one cam that face the first
bearing element and the second bearing element and two end faces of
the first bearing element and the second bearing element that face
the at least one cam form sliding surfaces of the axial
bearing.
20. The internal combustion engine according to claim 10, wherein
the first bearing element and the second bearing element are
structured for absorbing axial forces.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Application No.
DE 10 2020 201 038.2 filed Jan. 29, 2020, the contents of which are
hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a camshaft assembly, in
particular for an internal combustion engine of a motor vehicle,
and to an internal combustion engine having such a camshaft
assembly.
BACKGROUND
[0003] In internal combustion engines of motor vehicles, rotatably
mounted camshafts serve for adjusting inlet and exhaust valves of
the combustion chamber provided in a respective cylinder block.
[0004] There, the said rotatable mounting of the camshaft in a
fixed system--typically the said cylinder block of the internal
combustion engine--proves to be problematic since technically
involved and thus expensive to produce. Apart from this, the
rotatable mounting with conventional camshafts requires relatively
much installation space axially.
[0005] It is therefore an object of the present invention to show
new ways in the rotatable mounting of camshafts of internal
combustion engines. In particular, particularly cost-effective
or/and space-saving solutions are to be found.
[0006] This object is solved through the subject of the independent
patent claim(s). Preferred embodiments are subject of the dependent
patent claims.
SUMMARY
[0007] Accordingly, the basic idea of the invention is to rotatably
mount a camshaft by means of an axial bearing absorbing axial
forces, wherein one of the cams arranged on the camshaft is part of
such an axial bearing. Thus, a separate component in the axial
bearing which--as part of the axial bearing--absorbs axial forces
exerted on the axial bearing by the camshaft, can be dispensed
with. With the solution introduced here the cam that is
non-rotatably arranged on the camshaft in fact assumes this
function. In this way, the mounting of the camshaft compared with
conventional camshafts proves to be particularly simple. Apart from
this, the installation space needed in the axial direction is
reduced compared with conventional camshaft assemblies.
[0008] A camshaft assembly according to the invention, in
particular for an internal combustion engine of a motor vehicle,
comprises a camshaft extending along an axial direction, on which
at least one cam is non-rotatably arranged. Furthermore, the
camshaft assembly comprises an axial bearing for the axial
alignment of the camshaft. "Axial alignment" here means that the
axial bearing prevents an axial yielding of the camshaft, in
particular in the cylinder head of an internal combustion engine.
According to the invention, the cam arranged on the camshaft is
part of the axial bearing. Thus, the cam additionally assumes the
function of an axial bearing. The camshaft assembly of camshaft and
axial bearing according to the invention is therefore technically
constructed in a particularly simple manner in turn resulting in
the desired cost advantages during the production of the camshaft
assembly.
[0009] The camshaft assembly introduced here cannot only be
employed for the valve control in internal combustion engines but
also for driving a delivery device, for example a liquid pump, in
particular a fuel or coolant pump. Also conceivable is the use for
driving a sensor wheel.
[0010] According to a preferred embodiment, the axial bearing
comprises a first and a second axial bearing element which are
located opposite one another along the axial direction and between
which a cam is arranged. The two bearing elements and the said cam
are designed and matched to one another in such a manner that the
camshaft with the cam can rotate relative to the bearing elements
about a centre longitudinal axis of the camshaft extending along
the axial direction.
[0011] Particularly preferably, the cam is clamped in between the
two bearing elements so as to be rotatably adjustable about the
centre longitudinal axis of the camshaft.
[0012] According to another preferred embodiment, the axial bearing
comprises a first and a second cam which are arranged spaced apart
from one another and non-rotatably on the camshaft. Furthermore,
the axial bearing comprises a first and a second axial bearing
element. Preferably, the two bearing elements are arranged spaced
apart from one another along the axial direction. The two cams and
the two bearing elements in this embodiment are arranged relative
to one another on or at the camshaft in such a manner that the
first bearing element and the first cam limit an axial movement of
the camshaft in the axial direction and the second bearing element
and the second cam limit an axial movement of the camshaft opposite
to the axial direction.
[0013] Particularly preferably, the two bearing elements are
arranged between the two cams along the axial direction.
[0014] Alternatively to this and likewise particularly preferably,
the two cams can be arranged between the two bearing elements along
the axial direction.
[0015] According to a further advantageous further development, the
two axial end faces of the at least one cam facing the bearing
elements and the two axial end faces of the two bearing elements
facing the at least one cam each form sliding surfaces of the axial
bearing.
[0016] Particularly preferably, the bearing elements are designed
for absorbing axial forces. In this way, the desired axial guidance
of the camshaft is ensured without accompanying damage to or even
destruction of the bearing elements in particular in a long-term
operation of the assembly in a motor vehicle.
[0017] According to another advantageous further development, the
two bearing elements can each be designed as bearing sleeve with a
through-opening, through which the camshaft engages. In this way,
the camshaft can be rotatably mounted with little radial play.
Preferably, the two bearing sleeves, in the mounted state,
completely surround the cam, with the exception of the two
through-openings.
[0018] Particularly preferably, the two bearing elements or bearing
sleeves can be formed as identical parts. The use of identical
parts produces further cost advantages in the production of the
camshaft assembly.
[0019] According to a preferred embodiment, the axial bearing
consists of the cam and the two bearing elements. This embodiment
is a particularly simple design construction and thus
cost-effective in the production.
[0020] Apart from this, the invention relates to an internal
combustion engine, in particular for a motor vehicle. The internal
combustion engine comprises at least one cylinder block,
preferentially two or more cylinder blocks, which (in each case)
comprise(s) a combustion chamber and at least one adjustable valve
for introducing fresh air into the combustion chamber or for
discharging exhaust gas out of the combustion chamber. Furthermore,
the internal combustion engine comprises a camshaft assembly
according to the invention explained above. The advantages of the
camshaft assembly according to the invention explained above
therefore apply also to the internal combustion engine according to
the invention. Here, the two bearing elements of the axial bearing
of the camshaft assembly are arranged fixed in place relative to
the (respective) cylinder block. In the internal combustion engine
according to the invention, the cam of the axial bearing of the
camshaft assembly is drive-connected to the valve in order to
adjust the same.
[0021] According to a preferred embodiment of the internal
combustion engine, the camshaft is rotatably mounted on the
(respective) cylinder block by means of at least one radial
bearing. Combined with the axial bearing, the desired rotatability
of the camshaft relative to the cylinder block combined with the
likewise desired axial guidance or fixing materialises.
[0022] Further important features and advantages of the invention
are obtained from the subclaims, from the drawings and from the
associated figure description by way of the drawings.
[0023] It is to be understood that the features mentioned above and
still to be explained in the following cannot only be used in the
respective combination stated but also in other combinations or by
themselves without leaving the scope of the present invention.
[0024] Preferred exemplary embodiments of the invention are shown
in the drawings and are explained in more detail in the following
description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] It shows, in each case schematically:
[0026] FIG. 1 an example of an assembly according to the
invention,
[0027] FIG. 2 a version of the example of FIG. 1.
DETAILED DESCRIPTION
[0028] The FIG. 1 illustrates an example of a camshaft assembly 1
according to the invention for an internal combustion engine of a
motor vehicle. The camshaft assembly 1 comprises a camshaft 2
extending along an axial direction A. On the camshaft 2, multiple
cams 3 are arranged non-rotatably and spaced apart from one another
along the axial direction A. Here, the axial direction A extends
along a centre longitudinal axis M of the camshaft 2. A radial
direction R extends orthogonally to the axial direction away from
the centre longitudinal axis M. A circumferential direction U
circulates, perpendicularly both to the axial direction A and also
to the radial direction R, about the centre longitudinal axis
M.
[0029] Furthermore, the camshaft assembly 1 comprises an axial
bearing 4 for aligning or fixing the camshaft 2 along the axial
direction A. One of the cams 3--which in the following is referred
to with the reference number 3a--is part of this axial bearing 4.
In addition to the cam 3a, the axial bearing 4 comprises a first
and a second axial bearing element 5a, 5b. The two bearing elements
5a, 5b are formed as parts of the axial bearing 4 for absorbing
axial forces exerted by the cam 3a. To this end, the two bearing
elements 5a, 5b are arranged spaced apart from one another along
the axial direction A and lie opposite one another along the axial
direction A. The cam 3a co-forming the axial bearing 4 is arranged
along the axial direction A and between the two bearing elements
5a, 5b, namely in such a manner that the camshaft 2 with the cam 3a
can rotate relative to the two bearing elements 5a, 5b along the
circumferential direction U about the centre longitudinal axis M of
the camshaft 2. To this end, the cam 3a is clamped in between the
two bearing elements 5a, 5b so as to be rotatably adjustable along
the circumferential direction U. In the example scenario, the axial
bearing 4 consists of the cam 3a and the two bearing elements 5a,
5b, i.e. the axial bearing 4 is formed in three parts.
[0030] The two axial end faces 8 of the cam 3a facing the bearing
elements 5a, 5b and the two axial end faces 9 of the two bearing
elements 5a, 5b facing the cam 3a each form sliding surfaces of the
axial bearing 4. The two bearing elements 5a, 5b can each be formed
as bearing sleeve 6a, 6b with a through-opening 7a and 7b
respectively, through which the camshaft 2 engages as illustrated
in FIG. 1. Practically, the two bearing elements 5a, 5b and bearing
sleeves 6a, 6b respectively can be formed as identical parts.
[0031] Practically, one or more of the said sliding surfaces can be
provided with a protective coating (not shown), which can in
particular have a wear-reducing effect.
[0032] The camshaft assembly 1 of FIG. 1 can be used for example in
an internal combustion engine (not shown) for a motor vehicle. This
internal combustion engine comprises one, two or more cylinder
blocks, in each of which a combustion chamber and adjustable valves
for introducing fresh air into the combustion chamber and for
discharging exhaust gas out of the combustion chamber are provided.
Furthermore, the internal combustion engine comprises the camshaft
assembly 1 explained above. Here, the two bearing elements 5a, 5b
of the axial bearing 4 are preferably arranged fixed in place
relative to the respective cylinder block. In this way, the
camshaft 2 is axially guided relative to the cylinder block of the
internal combustion engine by means of the two bearing elements 5a,
5b. Here, the cam 3a of the axial bearing is drive-connected to one
of the adjustable valves.
[0033] The further cams 3 non-rotatably arranged on the camshaft 2,
which in contrast with the cam 3a are not part of the axial bearing
4, can be drive-connected to the remaining valves of the internal
combustion engine. The rotatable mounting of the camshaft 2 with
the cams 3 on the cylinder block can be realised by means of at
least one radial bearing (not shown).
[0034] FIG. 2 illustrates a version of the example of FIG. 1. Just
as in the example of FIG. 1, the assembly 1 according to FIG. 2
also comprises two bearing elements 5a, 5b which are arranged
spaced apart from one another along the axial direction A. The
example of FIG. 2 differs from the example of FIG. 1 in that the
axial bearing 4 comprises two cams 3a, 3b, which, spaced apart from
one another along the axial direction A, are non-rotatably arranged
on the camshaft 2. The two cams 3a, 3b and the two bearing elements
5a, 5b of the axial bearing 4 are arranged axially relative to one
another on or at the camshaft 2 in such a manner that the first
bearing element 5a and the first cam 3a limit an axial movement of
the camshaft 2 in the axial direction A and the second bearing
element 5b and the second cam 3b limit an axial movement of the
camshaft 2 opposite to the axial direction A. In this way, the
desired axial guidance of the camshaft 2 in the axial direction A
and opposite to the axial direction A can be realised analogously
to the example of FIG. 1. To this end, the two bearing elements 5a,
5b can be arranged between the two cams 3a, 3b along the axial
direction A as shown in FIG. 2. Alternatively to this it is also
conceivable however that the two cams 3a, 3b are arranged between
the two bearing elements 5a, 5b along the axial direction A (not
shown in FIG. 2).
* * * * *