U.S. patent application number 17/093243 was filed with the patent office on 2021-05-13 for camshaft arrangement.
The applicant listed for this patent is ECO Holding 1 GmbH, Mahle International GmbH. Invention is credited to Justus Himstedt, Dietmar Schulze, Andre Seidenschwann, Andre Selke, Stefan Steichele, Christoph Steinmetz.
Application Number | 20210140349 17/093243 |
Document ID | / |
Family ID | 1000005226890 |
Filed Date | 2021-05-13 |
United States Patent
Application |
20210140349 |
Kind Code |
A1 |
Seidenschwann; Andre ; et
al. |
May 13, 2021 |
CAMSHAFT ARRANGEMENT
Abstract
A camshaft arrangement includes an adjustable camshaft and an
adjuster for adjusting the camshaft. The adjustable camshaft
includes an outer shaft and an inner shaft arranged rotatably in
the outer shaft. The adjuster includes a stator connected with the
outer shaft in a rotationally fixed manner, and a rotor connected
in a rotationally fixed inner with the inner shaft via an axially
inserted coupling. A bush is connected with the rotor in a
rotationally fixed manner and has at least one channel for
supplying a lubricant. The bush has on a face side that axially
faces the inner shaft a form that together with a counter-form on
the inner shaft provides the axially inserted coupling.
Inventors: |
Seidenschwann; Andre;
(Erlensee, DE) ; Selke; Andre; (Lohr Am Main,
DE) ; Schulze; Dietmar; (Muenzenberg, DE) ;
Himstedt; Justus; (Stuttgart, DE) ; Steichele;
Stefan; (Gerlingen, DE) ; Steinmetz; Christoph;
(Ludwigsburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mahle International GmbH
ECO Holding 1 GmbH |
Stuttgart
Marktheidenfeld |
|
DE
DE |
|
|
Family ID: |
1000005226890 |
Appl. No.: |
17/093243 |
Filed: |
November 9, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01L 1/047 20130101;
F01L 1/344 20130101 |
International
Class: |
F01L 1/344 20060101
F01L001/344; F01L 1/047 20060101 F01L001/047 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 8, 2019 |
DE |
102019217295.4 |
Claims
1-11. (canceled)
12. A camshaft arrangement, comprising: an adjustable camshaft and
an adjuster for adjusting the camshaft, the camshaft having an
outer shaft and an inner shaft arranged rotatably in the outer
shaft, the outer shaft and the inner shaft respectively connected
with at least one associated cam in a rotationally fixed manner,
the adjuster including a stator connected with the outer shaft in a
rotationally fixed manner, and a rotor, the rotor connected in a
rotationally fixed manner with the inner shaft via an axially
inserted coupling, such that a rotation of the rotor relative to
the stator leads to a relative rotation of the inner shaft to the
outer shaft, a bush connected with the rotor in a rotationally
fixed manner and has at least one channel for supplying a
lubricant, the at least one channel in operation for supplying with
lubricant is fluidicially connected with a connection provided on
an outer casing, and wherein the bush has on a face side that
axially faces the inner shaft a form that together with a
counter-form on the inner shaft provides the axially inserted
coupling.
13. The camshaft arrangement according to claim 12, wherein the
coupling is configured as an Oldham coupling.
14. The camshaft arrangement according to claim 12, wherein: the
outer shaft projects axially over the inner shaft with a receiving
section on the side facing the bush, and the bush is rotatably
arranged in the receiving section.
15. The camshaft arrangement according to claim 14, further
comprising at least one elastic seal arranged radially between an
outer shaft inner side of the receiving section and a bush outer
side of the bush.
16. The camshaft arrangement according to claim 15, further
comprising a slide ring arranged radially between the outer shaft
inner side or the bush outer side and the at least one elastic
seal.
17. The camshaft arrangement according to claim 12, wherein the
bush is arranged radially freely in the outer shaft.
18. The camshaft arrangement according to claim 12, wherein the
rotor is rotatably mounted via a radially exterior outer shaft
outer side of the outer shaft.
19. The camshaft arrangement according to claim 18, wherein: the
outer shaft has a projection, protruding axially and penetrating
into the adjuster, and the rotor is rotatably mounted on the outer
shaft outer side of the projection.
20. The camshaft arrangement according to claim 12, further
comprising: a pin that penetrates axially into the bush and
connects the bush with the rotor in a rotationally fixed manner,
and wherein the pin has a pin cavity that is fluidically connected
with the interior of the bush.
21. The camshaft arrangement according to claim 12, further
comprising a drive wheel for driving the camshaft, wherein the
drive wheel is formed in one part with the stator.
22. The camshaft arrangement according to claim 15, wherein: the
bush has a bush cavity that is closed on the side facing the form,
the bush has at least two channels, spaced axially with respect to
one another, and are respectively connected fluidically with the
bush cavity, and the at least two channels are arranged axially
between two seals.
23. An internal combustion engine system, comprising: an internal
combustion engine having at least two valves, and a camshaft
arrangement for actuating the at least two valves, the camshaft
arrangement including: an adjustable camshaft and an adjuster for
adjusting the camshaft, the camshaft having an outer shaft and an
inner shaft arranged rotatably in the outer shaft, the outer shaft
and the inner shaft respectively connected with at least one
associated cam in a rotationally fixed manner, the adjuster
including a stator connected with the outer shaft in a rotationally
fixed manner, and a rotor, the rotor connected in a rotationally
fixed manner with the inner shaft via an axially inserted coupling,
such that a rotation of the rotor relative to the stator leads to a
relative rotation of the inner shaft to the outer shaft, a bush
connected with the rotor in a rotationally fixed manner and having
at least one channel for supplying a lubricant, the at least one
channel in operation for supplying with lubricant is fluidicially
connected with a connection provided on an outer casing, wherein
the bush has on a face side that axially faces the inner shaft a
form that together with a counter-form on the inner shaft provides
the axially inserted coupling.
24. The internal combustion engine system according to claim 23,
wherein the axially inserted coupling is configured as an Oldham
coupling.
25. The internal combustion engine system according to claim 23,
wherein the outer shaft projects axially over the inner shaft with
a receiving section on the side facing the bush, and the bush is
rotatably arranged in the receiving section.
26. The internal combustion engine system according to claim 25,
wherein the camshaft arrangement further includes at least one
elastic seal arranged radially between an outer shaft inner side of
the receiving section and a bush outer side of the bush.
27. The internal combustion engine system according to claim 25,
wherein the bush is arranged radially freely in the outer
shaft.
28. The internal combustion engine system according to claim 23,
wherein the rotor is rotatably mounted via a radially exterior
outer shaft side of the outer shaft.
29. The internal combustion engine system according to claim 28,
wherein the outer shaft has a projection protruding axially and
penetrating into the adjuster, and wherein the rotor is rotatably
mounted on the outer shaft outer side of the projection.
30. The internal combustion engine system according to claim 23,
further comprising a pin that penetrates axially into the bush and
connects the bush with the rotor in a rotationally fixed manner,
wherein the pin has a pin cavity that is fluidically connected with
an interior of the bush.
31. The internal combustion engine system according to claim 23,
further comprising a drive wheel for driving the camshaft, wherein
the drive wheel is formed in one part with the stator.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Application No.
DE 10 2019 217 295.4 filed Nov. 8, 2019, the contents of which are
hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a camshaft arrangement with
an adjustable camshaft and with an adjuster for adjusting the
camshaft. The invention relates furthermore to an internal
combustion engine system with an internal combustion engine and
with such a camshaft arrangement.
BACKGROUND
[0003] A camshaft usually comes into use for the actuating of
valves of an internal combustion engine. For this purpose, the
camshaft has cams arranged on a shaft in a rotationally fixed
manner, which cams actuate respectively associated valves
accordingly.
[0004] In order to increase the variability of the actuation of the
valves, so-called adjustable camshafts, also designated as
phase-adjustable camshafts, are known for example from DE 10 2015
224 012 A1. Such a camshaft has an outer shaft and an inner shaft
arranged in the outer shaft, which inner shaft is rotatable
relative to the outer shaft. The respective shaft is connected with
associated cams, so that a relative rotation between the inner
shaft and the outer shaft leads to a phase shift between the cams
of the outer shaft and the cams of the inner shaft.
[0005] In the production and in the operation of such adjustable
camshafts, it is important to precisely maintain a relative
alignment of the inner shaft to the outer shaft, as offsets between
the inner shaft and the outer shaft lead to increased friction and
therefore in particular to an increased wear and/or a reduced
lifespan. In addition, such offsets can lead to a jamming of the
inner shaft on the outer shaft, which disturbs the operation of the
camshaft and/or blocks an adjusting of the camshaft.
[0006] For adjusting the camshaft, i.e. for the relative rotational
movement between the inner shaft and the outer shaft, usually
adjusters are used, which are connected with a stator in a
rotationally fixed manner, and with a rotor in a rotationally fixed
manner with the inner shaft.
[0007] Such a camshaft arrangement with an adjustable camshaft and
with an associated adjuster is known from DE 10 2014 206 291 A1. In
DE 10 2014 206 291 A1 it is proposed to connect the rotor of the
adjuster with the inner shaft via an Oldham coupling, in order to
compensate offsets between the inner shaft and the outer shaft in
axial and angular direction. Here, a contour or form is provided on
the inner shaft, and a counter-form or counter-contour is provided
on an intermediate part which is connected with the rotor in a
rotationally fixed manner, for the formation of the Oldham
coupling. In addition, a sleeve for supplying the camshaft
arrangement with a fluid for the simultaneous actuation and
lubrication penetrates axially through the intermediate part, and
into the inner shaft.
[0008] A disadvantage in camshaft arrangements which are known from
the prior art are the complicated construction and the continual
lack of compensation of offsets between the inner shaft and the
outer shaft.
SUMMARY
[0009] The present invention is therefore concerned with the
problem of indicating, for a camshaft arrangement of the
above-mentioned type and for an internal combustion engine system
with such a camshaft arrangement, improved or at least different
embodiments, which in particular are distinguished by a simplified
construction and/or by an improved compensation of offsets.
[0010] This problem is solved according to the invention by the
subjects of the independent claims. Advantageous embodiments are
the subject of the dependent claims.
[0011] The present invention is based on the general idea of
realizing, in a camshaft arrangement with an adjustable camshaft
and with an adjuster for adjusting the camshaft, an axially
inserted form-fitting connection as a coupling between a rotor of
the adjuster and an inner shaft of the camshaft via an already
present bush for supplying the arrangement with lubricant.
Therefore, an additional intermediate part for realizing the
form-fitting connection between the rotor and the inner shaft can
be dispensed with, and the construction of the camshaft arrangement
can thus be simplified. The omission of the additional intermediate
part leads, furthermore, to an improved compensation of offsets
between the inner shaft and the outer shaft of the camshaft, in
particular of offsets in axial direction and/or angular offsets,
i.e. offsets in circumferential direction.
[0012] In accordance with the idea of the invention, the camshaft
arrangement has the adjustable camshaft and the adjuster. The
camshaft has an outer shaft and an inner shaft arranged rotatably
in the outer shaft, wherein the outer shaft and the inner shaft are
respectively connected in a rotationally fixed manner with at least
one associated cam. The adjuster has a stator and the rotor. Here,
the stator is connected with the outer shaft in a rotationally
fixed manner. The rotor is connected in a rotationally fixed manner
with the bush, by which a supply of the arrangement with lubricant
takes place. The bush has here at least one channel which in
operation is connected with a connection for the fluidic supply of
the arrangement by lubricant, wherein the connection is provided on
an outer casing of the arrangement. According to the invention, the
bush has on its face side facing the inner shaft axially, a form
which, with a counter-form on the inner shaft, forms the axially
inserted form-fitting connection and thus the coupling. With the
realizing of the coupling between the rotor and the inner shaft via
the bush, therefore with a simple construction a compensation of
axial offsets and/or radial offsets of the inner shaft to the outer
shaft takes place.
[0013] The directions indicated in the present case refer in
particular to an axis of the outer shaft. The axial direction
therefore corresponds in particular to the rotation axis of the
outer shaft. The angular direction corresponds accordingly to the
circumferential direction surrounding the axial direction. The
lateral direction corresponds accordingly to a radial direction
running perpendicularly to the axial direction. Accordingly, axial
offsets of the inner shaft to the outer shaft are relative
displacements of the inner shaft to the outer shaft in axial
direction, angular offsets are relative movements of the inner
shaft to the outer shaft in circumferential direction and lateral
offsets are relative movements of the inner shaft to the outer
shaft in radial direction.
[0014] An axially inserted form-fitting connection and therefore an
axially inserted coupling is to be understood here to mean a
coupling having the form on the bush and the counter-form on the
inner shaft, wherein the form and counter-form are inserted axially
into one another and therefore produce a rotationally fixed
connection between the inner shaft and the rotor, which is
connected with the bush in a rotationally fixed manner.
[0015] The coupling is preferably configured as an Oldham coupling.
The coupling can therefore be implemented easily and at a
favourable cost.
[0016] It is also conceivable to configure the coupling as an
elastomer coupling.
[0017] In addition to lubricating, the lubricant also serves for
actuation, in particular for adjusting the inner shaft relative to
the outer shaft. Accordingly, the lubricant is preferably a fluid.
In particular, the lubricant is lubricating oil. The bush is
therefore in particular an oil guide bush.
[0018] The bush is expediently arranged axially between the rotor
and the inner shaft. It is preferred when the bush is connected not
only in a rotationally fixed manner with the rotor, but is fixed on
the rotor, so that the bush is also connected axially and laterally
securely with the rotor.
[0019] The counter-form provided on the inner shaft can be formed
integrally on the inner shaft. Therefore, a simple construction of
the arrangement and a reliable compensation of offsets with the aid
of the coupling are possible.
[0020] It is also conceivable to provide between the face side of
the bush and therefore between the form and the inner shaft an
intermediate part with the counter-form, which is arranged on the
inner shaft.
[0021] Embodiments are preferred in which the outer shaft projects
axially over the inner shaft, on the side facing the bush, with a
receiving section, wherein the bush is rotatably arranged in the
receiving section of the outer shaft. This means that the bush is
received and rotatably arranged in the outer shaft. This leads to a
compact construction of the camshaft arrangement and a simple
implementation of the coupling.
[0022] Embodiments prove to be advantageous in which at least one
elastic seal is arranged between a radial inner side of the outer
shaft, hereinbelow also designated as outer shaft inner side, in
the receiving section, and a radial outer side of the bush,
hereinafter also designated as bush outer side. Therefore, a
fluidic sealing of the receiving region is achieved. In particular,
the flowing of the lubricant from the receiving region is thus
prevented or at least reduced. It is preferred here if at least two
seals, spaced apart axially with respect to one another, are
provided. An axial flowing of the lubricant in both axial
directions is thus at least reduced.
[0023] It is preferred if at least one of the at least one seals is
arranged and received in an associated, radially open outer groove
in the outer shaft inner side or respectively in the bush outer
side, advantageously in the bush outer side.
[0024] It is preferred here when the seal is arranged radially
between the bush outer side and the associated slide ring.
[0025] Advantageously, an associated slide ring is arranged
radially between at least one of the at least one seals, preferably
the respective seal, and the outer shaft inner side or the bush
outer side. Preferably, the slide ring is arranged radially between
the associated seal and the outer shaft inner side. The slide ring
serves here for the protection of the seal during relative
movements, in particular rotations, between the outer shaft and the
inner shaft. Thus, in particular, the transmission of shearing
forces to the seal is prevented or at least reduced. Consequently,
damage to the seal is reduced, so that a sealing takes place with
the seal for a longer duration.
[0026] At least one of the at least one slide rings is
advantageously a slotted slide ring, i.e. interrupted in
circumferential direction. The slide ring can therefore be mounted
in particular in a simplified manner. Rectangular rings are also
conceivable.
[0027] The elastic seal can be configured basically in any desired
manner. In particular, the seal is a ring seal. This leads to a
homogeneous and/or improved sealing effect. Embodiments are also
conceivable in the form of slide- or respectively rectangular rings
with reduced adhesion- and sliding friction coefficient for an
improved response behaviour and reduced losses in operation. In
particular PTFE-coated rings are advantageous for this.
[0028] With the at least one seal and the coupling, the bush is
advantageously arranged radially freely in the outer shaft. This
means in particular to be spaced apart more radially between the
bush to the outer shaft and/or that a bearing of the bush in the
outer shaft can be dispensed with. Therefore, the outer shaft
and/or the bush can be produced in a simplified manner. In
particular, the outer shaft can be produced radially on the inner
side and/or the bush can be produced radially on the outer side
with higher tolerances. In particular, a fine processing of the
outer shaft inner side can be dispensed with. In addition, in this
way a simpler relative positioning of the rotor to the inner shaft
is possible. In particular, in this way an exact lateral
positioning of the rotor to the inner shaft can be dispensed
with.
[0029] Alternatively or additionally, the rotor can be rotatably
mounted via a radially exterior outer side of the outer shaft,
hereinbelow also designated as outer shaft outer side. In
particular, the rotor can be rotatably mounted exclusively via the
outer shaft outer side. This leads in particular to the fact that a
separate processing of the outer shaft inner side can be dispensed
with, so that the outer shaft as a whole can be produced at a more
favourable cost. In particular, it is thus possible to produce the
outer shaft inner side with increased tolerances. At the same time,
via the rotatably mounting of the rotor on the outer shaft outer
side, a compensation and/or reduction of lateral offsets between
the inner shaft and the outer shaft is achieved.
[0030] The mounting of the rotor on the outer shaft outer side is
advantageously realized in such a way that the outer shaft has an
axial projection which penetrates into the adjuster, in particular
projects over the bush in axial direction. Here, the rotor is
rotatably mounted on the outer shaft outer side of the projection.
This leads in particular to the mounting of the rotor on the outer
shaft being implemented in an installation-space-saving and
efficient manner. In particular, in this way, owing to the vicinity
of the rotor to the projection, a simple mounting of the rotor on
the outer shaft can take place.
[0031] The rotationally fixed connection of the rotor with the
bush, in particular the fixing of the rotor on the bush, is
preferably realized via a pin which can be a component part of a
screw. In particular, the pin can have an external thread which
forms a screw connection with an internal thread of the bush. Here,
a screw head or a nut of the screw connection can act upon the
rotor axially against the bush, in such a way that a rotationally
fixed connection of the rotor with the bush is provided.
[0032] The pin has advantageously in the interior a cavity, which
is also designed hereinbelow as pin cavity. It is preferred here if
the pin cavity is fluidically connected with the interior of the
bush, in particular a cavity formed in the interior of the bush,
designated hereinbelow also as bush cavity. In this way, it is
possible in particular to realize the feeding and the discharging
of the lubricant via the bush and the pin.
[0033] The camshaft arrangement expediently has a drive wheel which
serves for driving the camshaft. The drive wheel is expediently
connected with the stator in a rotationally fixed manner. The drive
wheel can be driven in an associated system with an internal
combustion engine, hereinbelow also designated internal combustion
engine system, by a crankshaft of the internal combustion engine.
Here, the drive wheel can be, in particular, a spur wheel.
[0034] It is conceivable here to form the drive wheel and the
stator in a single part. This means in particular that the drive
wheel and the stator can be fixed to one another via a materially
bonded connection or a force-fitting connection.
[0035] In addition, it is conceivable to form the drive wheel and
the stator in a single piece. In particular, the drive wheel and
the stator can be produced jointly, for example by sintering.
[0036] An easy centring of the stator to the outer shaft can be
achieved when the stator is connected directly or indirectly with
the receiving section of the outer shaft. Thus, an easy centring of
the adjuster relative to the outer shaft and/or to the inner shaft
also takes place.
[0037] For centring the adjuster, alternatively or additionally at
least one centring collar can be provided, for example on the drive
wheel.
[0038] The bush can have, as mentioned above, a bush cavity which
in particular serves for supplying the arrangement with the
lubricant. The bush cavity is expediently closed on the side
axially facing the form and therefore on the side axially facing
the inner shaft.
[0039] The bush preferably has at least two channels, spaced
axially with respect to one another, which are connected
respectively fluidically with the bush cavity, wherein the channels
are arranged axially between two slide rings. This leads to an
improved mounting of the bush and therefore of the rotor in the
inner shaft. It is advantageous here if for the respective slide
ring an associated seal of the described type, therefore an elastic
seal in radial direction, is provided. Thus in particular the
region which is flowed through fluidically in operation is sealed
in an improved manner.
[0040] It is advantageous if the bush in addition has at least two
such channels spaced apart from one another in circumferential
direction. Consequently in operation an improved supplying of the
arrangement with lubricant takes place.
[0041] It shall be understood that in addition to the camshaft
arrangement also an internal combustion engine system with such a
camshaft arrangement belongs to the scope of this invention. The
internal combustion engine system comprises, in addition to the
camshaft arrangement, the internal combustion engine which has at
least two valves which are actuated in operation by the cams of the
camshaft.
[0042] Further important features and advantages of the invention
will emerge from the subclaims, from the drawings and from the
associated figure description with the aid of the drawings.
[0043] It shall be understood that the features mentioned above and
to be explained further below are able to be used not only in the
respectively indicated combination, but also in other combinations
or in isolation, without departing from the scope of the present
invention.
[0044] Preferred example embodiments of the invention are
illustrated in the drawings and are explained in further detail in
the following description, wherein the same reference numbers refer
to identical or similar or functionally identical components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] There are shown, respectively schematically
[0046] FIG. 1 a lateral view, partially in section, of a camshaft
arrangement,
[0047] FIG. 2 a frontal view onto a bush of the camshaft
arrangement,
[0048] FIG. 3 a longitudinal section through the bush,
[0049] FIG. 4 an isometric view of the bush,
[0050] FIG. 5 a section through the camshaft arrangement in the
region of the bush,
[0051] FIG. 6 an isometric view of a slide ring of the camshaft
arrangement,
[0052] FIG. 7 a longitudinal section through the camshaft
arrangement in another example embodiment.
DETAILED DESCRIPTION
[0053] A camshaft arrangement 1, as shown for example in FIGS. 1 to
7, serves in an otherwise not shown internal combustion engine
system 2 for the actuation of valves, which are not shown, of an
internal combustion engine, which is not shown. As can be seen in
particular from FIG. 1, the camshaft arrangement 1 has an
adjustable camshaft 3 with a hollow outer shaft 4 and an inner
shaft 5, which is rotatably arranged in the outer shaft 4. The
outer shaft 4 is rotatable about a rotation axis 6, which
corresponds to an axial direction 7. In an optimum arrangement, the
inner shaft 5 and the outer shaft 4 are coaxially arranged, i.e.
the inner shaft 5 and the outer shaft 4 have the same rotation axis
6. On the outer shaft 4 at least one associated cam 8 is mounted in
a rotationally fixed manner, by which a valve of the internal
combustion engine can be actuated. In addition, an associated cam
38 is mounted in a rotationally fixed manner on the inner shaft 5,
by which a valve of the internal combustion engine can be actuated.
The camshaft arrangement 1 of FIG. 1 can have, furthermore, a drive
wheel 9, which is connected with the outer shaft 4 in a
rotationally fixed manner and thus rotates the outer shaft 4. For
the relative rotating of the inner shaft 5 to the outer shaft 4 and
thus for adjusting the camshaft 3, the camshaft arrangement 1 has
an adjuster 10. The adjuster 10 has a stator 11 which is connected
with the outer shaft 4 in a rotationally fixed manner. The stator
11 is connected, for example via screw connections 13, with the
drive wheel 9 in a rotationally fixed manner. The adjuster 10 has,
in addition, a rotor 12 connected with the inner shaft 5 in a
rotationally fixed manner, which rotor is rotatable relative to the
stator 11, wherein this takes place via a corresponding rotation of
the rotor 12 to the stator 11. In the example embodiment shown in
FIG. 1, the stator 11 is arranged radially between the drive wheel
9 and the outer shaft 4. The rotor 12 is arranged axially on the
face side of the drive wheel 9. In FIG. 1 a side view of the
camshaft arrangement 1 can be seen, wherein the camshaft
arrangement 1 is shown axially between the adjuster 10 and the
inner shaft 5 in an axially running longitudinal section, which
runs centrally radially.
[0054] As can be seen from FIG. 1, the camshaft arrangement 1,
hereinbelow also abbreviated as arrangement 1, has a bush 14 which
serves for supplying the arrangement 1 with a lubricant, in
particular with oil. The lubricant, in addition to lubricating,
serves furthermore for the actuation, in particular for the
relative moving, of the inner shaft 5 to the outer shaft 4. For
this purpose, in operation the bush 4 is supplied fluidically with
the lubricant via at least one connection 15 provided on an outer
casing of the arrangement 1, wherein in the example embodiment
shown in FIG. 1 two such connections 15 are provided, one of which
serves for the feeding of the lubricant and the other serves for
the discharging of the lubricant. For the respective connection 15,
the bush 14 has at least one channel 16, which fluidically connects
a cavity 17, formed in the interior of the bush 14, hereinbelow
also designated as bush cavity 17, with the associated connection
15. In the examples which are shown, the bush 14 has for the
respective connection 15 at least two associated channels 16, which
are spaced apart from one another in a circumferential direction
37. The respective channel 16 runs here radially through the bush
14.
[0055] As can be seen in particular from FIG. 1, the rotor 12 is
connected via the bush 14 in a rotationally fixed manner with the
inner shaft 5. Here, the bush 14 is arranged axially between the
rotor 12 and the inner shaft 5. For the rotationally fixed
connection of the rotor 12 with the inner shaft 5, the bush 14 has,
on its face side 18 facing the inner shaft 5 axially, a form 19
which is axially inserted with a counter-form 20 on the inner shaft
4 and thus forms an axially inserted coupling 21. For this purpose,
in the example embodiments which are shown, an intermediate piece
23, having the counter-form 20, is mounted on the inner shaft 5 in
a rotationally fixed manner and Is arranged axially between the
face side 18 of the bush 14 and the inner shaft 5. FIG. 2 shows
here a frontal view in axial direction 7 onto the face side 18 and
thus onto the form 19, and FIG. 3 shows the section, designed by
III in FIG. 2, in axial direction 7 through the bush 14. FIG. 4
shows an isometric view of the bush 14.
[0056] In the example embodiments which are shown, the coupling 21
is configured as an Oldham coupling 22.
[0057] As can be seen in particular from FIG. 3, in the example
embodiments which are shown, the bush 14 is configured to be closed
on the side facing the face side 18 and to be open on the side
facing away from the face side 18. In the example embodiments which
are shown, the rotationally fixed connection of the rotor 12 with
the bush 14 takes place via a pin 24, which is a component part of
a screw 25 with a screw head 26. For this purpose, the pin 24 has
an external thread, which is not shown, which interacts with an
internal thread, not shown, in the cavity 17 of the bush 14,
wherein the screw head 26 presses the rotor 12 axially in the
direction of the bush 14 and thus connects the rotor 12 with the
bush 14 in a rotationally secure manner.
[0058] As can be seen from FIG. 1, the pin 24 in the example
embodiments which are shown is of hollow design and has in its
interior a cavity 27, which is also designated below as pin cavity
27. The pin cavity 27 is open on the side axially facing the bush
14 or respectively the inner shaft 5, so that the pin cavity 27 and
the bush cavity 17 are fluidically connected with one another.
[0059] As can be seen from FIGS. 1, 3 and 4, the outer shaft 4
projects in axial direction 7 beyond the inner shaft 5 and has a
receiving section 28 projecting over the inner shaft 5, in which
receiving section the bush 14 is received and rotatably arranged.
Here, the connections 15 are respectively formed in the receiving
section 28 of the outer shaft 4. Hereby, via the drive wheel 9,
which is connected with the stator 11 and is mounted on the
receiving section 28, a centring of the adjuster 10, in particular
of the stator 11, to the outer shaft 4 also takes place.
[0060] As can be seen in particular from viewing FIGS. 1, 3 and 4
together, in the example embodiment shown in FIGS. 1 to 5, the bush
14, and consequently the rotor 12, is arranged rotatably within the
receiving section 28. Here, the outer shaft 4 has a radially
interior inner side 29, also designated below as outer shaft inner
side 29. The bush 14 has a radially exterior outer side 30, also
designated below as bush outer side 30. Radially between the outer
shaft inner side 29 and the bush outer side 30, at least one
elastic seal 32, in particular a ring seal 33, is arranged, by
which in particular a flowing off of the lubricant is prevented or
at least reduced. In the example embodiment which is shown, two
such seals 32 are used, which are spaced apart from one another in
axial direction 7, wherein the channels 18 of the bush 14 and the
connections 15 are arranged axially between the seals 32.
Consequently, a flowing off of the lubricant in both directions is
prevented or at least reduced. The bush 14 has here on the bush
outer side 30 for the respective seal 32 a radially outwardly open
and annular outer groove 34, in which the seal 32 is received.
[0061] In FIG. 5 a section is shown through the camshaft
arrangement 1 in the region of such a seal 32.
[0062] As can be seen in particular from FIG. 5, an associated
slide ring 31 is arranged radially between the respective seal 32
and the outer shaft inner side 29 or the bush outer side 30. In the
example embodiment which is shown, and preferably, the respective
slide ring 31 is arranged radially between the seal 32 and the
outer shaft inner side 29. With the slide ring, a protection takes
place of the associated seal 32 with respect to relative movements,
in particular rotations, between the inner shaft 5 and the outer
shaft 4. Such a slide ring 31 is illustrated in FIG. 6 separately
and isometrically. It can be seen from FIG. 6 that the slide ring
31 is interrupted in circumferential direction 37 and is thus
configured to be slotted.
[0063] The seals 32 and the coupling 21 allow the bush 14 to be
positioned radially freely in the outer shaft 4. A mounting of the
bush 14 in the outer shaft 4 can thus be dispensed with.
[0064] Another example embodiment of the camshaft arrangement 1 is
shown in FIG. 7, wherein FIG. 7 shows a section through the
camshaft arrangement 1 in axial direction 7 and thus a longitudinal
section, and wherein the rotor 12 is not illustrated. The example
embodiment shown in FIG. 7 differs from the example embodiment
shown in FIGS. 1 to 6 in that the rotor 12, which is not shown in
FIG. 7, is rotatably mounted on a radially exterior outer side 35
of the outer shaft 4, also designated below as outer shaft outer
side 35. The bush 14 is thus also rotatably mounted via the rotor
12 on the outer shaft outer side 35, so that a mounting on the
outer shaft inner side 29 can be dispensed with. For mounting the
rotor 12 on the outer shaft outer side 35, the outer shaft 4 in the
example embodiment shown in FIG. 7 has a projection 36 penetrating
axially into the adjuster 10, wherein the rotor 12 is rotatably
mounted on the outer shaft outer side 35 of the projection 36.
Here, seals 32, in particular ring seals 33, radially between the
outer shaft inner side 29 and the bush outer side 30, can be
received in the outer grooves 34, in order to achieve a
corresponding sealing. In the example embodiment shown in FIG. 7,
it is illustrated that the stator 11 for rotationally fixed
connection with the outer shaft 4 can be mounted on the outer shaft
outer side 35 in a rotationally fixed manner, in particular can be
shrunk on.
[0065] The respective camshaft arrangement 1 compensates via the
coupling 21 an axial and angular offset between the inner shaft 5
and the outer shaft 4. Through the mounting of the rotor 12 and of
the bush 14 on the outer shaft, in addition a lateral offset is
compensated between the inner shaft 5 and the outer shaft 4. In
addition, in this way the respective camshaft arrangement 1 is able
to be produced in a compact and simple manner.
* * * * *