U.S. patent application number 09/813385 was filed with the patent office on 2001-10-11 for device for changing the timing of intake and exhaust valves in an internal combustion engine.
Invention is credited to Dietz, Joachim, Strauss, Andreas.
Application Number | 20010027761 09/813385 |
Document ID | / |
Family ID | 7635697 |
Filed Date | 2001-10-11 |
United States Patent
Application |
20010027761 |
Kind Code |
A1 |
Dietz, Joachim ; et
al. |
October 11, 2001 |
Device for changing the timing of intake and exhaust valves in an
internal combustion engine
Abstract
A device for changing the timing of valves in an internal
combustion engine which includes a crankshaft-coupled component and
a camshaft-coupled component is provided. The camshaft-coupled
component is hydraulically rotatable and lockable with respect to
the crankshaft-coupled component for relative rotation or hydraulic
clamping of the camshaft (5) with respect to the crankshaft.
Movement of hydraulic fluid to and from the device proceeds via a
hydraulic-fluid adapter on the device's axial side facing away from
the camshaft, against which adapter is additionally positioned an
impulse-sending wheel for determining the camshaft position. The
hydraulic-fluid adapter includes a diametrically expanded end
flange which simultaneously forms the impulse-sending wheel of the
device and, together with a washer positioned between the
hydraulic-fluid adapter and the camshaft-coupled component that is
likewise diametrically enlarged with respect to the hydraulic-fluid
adapter, acts as the axial bearing of the camshaft.
Inventors: |
Dietz, Joachim; (Frensdorf,
DE) ; Strauss, Andreas; (Forchheim, DE) |
Correspondence
Address: |
VOLPE AND KOENIG, P.C.
SUITE 400, ONE PENN CENTER
1617 JOHN F. KENNEDY BOULEVARD
PHILADELPHIA
PA
19103
US
|
Family ID: |
7635697 |
Appl. No.: |
09/813385 |
Filed: |
March 21, 2001 |
Current U.S.
Class: |
123/90.15 |
Current CPC
Class: |
F01L 1/46 20130101; F01L
1/34 20130101; F01L 1/344 20130101 |
Class at
Publication: |
123/90.15 |
International
Class: |
F01L 001/34 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 21, 2000 |
DE |
100 13 877.2 |
Claims
What is claimed is:
1. Device for changing the timing of intake and exhaust valves in
an internal combustion engine of the hydraulic servo-drive type
comprising: at least one axial fastening bolt (2) for connecting
the device (1) to a drive-side end (3) of a camshaft (5) supported
in the cylinder head (4) of the internal combustion engine; a
crankshaft-coupled component (6) driven together with a crankshaft
of the internal combustion engine and a camshaft-coupled component
(7) rotationally connected with the camshaft (5); the
camshaft-coupled component (7) is hydraulically rotatable and
lockable with respect to the crankshaft-coupled component (6) to
effect a relative rotation or a hydraulic clamping of the camshaft
(5) with respect to the crankshaft; a cylindrical hydraulic-fluid
adapter (9,9') positioned on the device's axial side (8) facing
away from the camshaft for supplying and withdrawing hydraulic
fluid to and from the device (1) attached to the camshaft-coupled
component (7); the hydraulic-fluid adapter (9) includes a plurality
of hydraulic-fluid lines (10, 11, 12) and is supported in a sleeve
bearing (13) in or on the cylinder head (4) of the internal
combustion engine, the bearing being forming part of a
hydraulic-fluid circuit and simultaneously acting as a radial
bearing of the camshaft (5); an impulse-sending wheel (15,15') for
determining the camshaft position with respect to the crankshaft
position connected to an end wall (14) of the hydraulic-fluid
adapter (9,9') facing away from the camshaft axially to the
camshaft (5); a diametrically expanded end flange (16) is connected
to the end wall (14) of the hydraulic-fluid adapter (9) facing away
from the camshaft which simultaneously forms the impulse-sending
wheel (15) of the device (1) and, together with a washer (17)
positioned between the hydraulic-fluid adapter (9) and the camshaft
coupled component (7) which is diametrically enlarged with respect
to the hydraulic-fluid adapter (9), an axial bearing for the
camshaft (5).
2. Apparatus according to claim 1, wherein the axial fastening bolt
(2) of the device (1) includes a head (18) that is positioned at
least partially in a countersink (19) in the end wall (14) of the
hydraulic-fluid adapter (9) facing away from the camshaft.
3. Device for changing the timing of intake and exhaust valves in
an internal combustion engine of claim 1, wherein --the
impulse-sending wheel (15') of the device (1) is positioned against
the end wall (14) of the hydraulic-fluid adapter (9') facing away
from the camshaft has a greater diameter than the hydraulic-fluid
adapter (9') and, together with the washer (17) positioned between
the adapter and the camshaft-coupled component (7), acts as the
axial bearing for the camshaft (5).
4. Apparatus according to claim 3, wherein the impulse-sending
wheel (15') is a cup-shaped sheet-metal piece which is separately
attached by an additional nut (20) to a head (18) of the axial
fastening bolt (2) of the device (1) and radially surrounds the nut
(20).
Description
BACKGROUND
[0001] The present invention concerns a device for changing the
timing of intake and exhaust valves in an internal combustion
engine according to the features in the introductory portion of
claim 1, which is especially advantageous for to hydraulic camshaft
adjustment mechanisms.
[0002] Such a device is already generically known from German
Patent Publication DE 197 45 670 A1. This device, essentially
designed as a hydraulic servo-drive, is positioned at the
drive-side end of a camshaft supported in the cylinder head of an
internal combustion engine and consists of one component driven
together with a crankshaft of the internal combustion engine as
well as of another component rotationally connected with the
camshaft. The camshaft-coupled component is hydraulically rotatable
and lockable with respect to the crankshaft-coupled component and
thus effects a relative rotation or a hydraulic clamping of the
camshaft with respect to the crankshaft. The supply and withdrawal
of hydraulic fluid to and from the device proceeds via a
cylindrical hydraulic-fluid adapter positioned on the device's
axial side facing away from the camshaft and attached to the
camshaft-coupled component. This adapter includes several
hydraulic-fluid lines running in the axial, radial, and
circumferential direction and is supported in a sleeve bearing in
the cylinder head of the internal combustion engine. The sleeve
bearing is connected with the hydraulic-fluid circuit and is
designed at the same time as the radial bearing of the camshaft. In
addition, there is attached to the end wall of the hydraulic-fluid
adapter, facing away from the camshaft, an impulse-sending wheel
which cooperates with a suitable impulse-reading device and
together with the latter serves in determining the camshaft
position with respect to the crankshaft position during operation
of the internal combustion engine.
[0003] In this known solution, however, it is disadvantageous that
the required axial support of the camshaft connected with the
device must be formed by a separate axial bearing on the camshaft
so that precise machining of the camshaft and thus relatively high
production costs are involved in its manufacture. In addition, such
an axial bearing requires in connection with the impulse-sending
wheel attached to the device an increased overall axial length of
the camshaft and thus of the total cylinder head of the internal
combustion engine, which, however, is frequently not possible with
due to the usually very restricted space conditions in the engine
compartment of the vehicle.
SUMMARY
[0004] The present invention is directed to providing a device for
changing the timing of intake and exhaust valves in an internal
combustion engine in which the high production costs for an axial
bearing on the camshaft as well as the overall axial length of the
camshaft necessary for this axial bearing and for the
impulse-sending wheel attached to the device can be reduced to a
minimum.
[0005] This problem is solved according to the present invention
for a device for changing the valve timing of an internal
combustion engine by providing the hydraulic-fluid adapter on its
end wall facing away from the camshaft with a diametrically
expanded end flange which, on the one hand, simultaneously forms
the impulse-sending wheel of the device and, on the other hand, is
designed--together with a washer positioned between the
hydraulic-fluid adapter and the component coupled to the camshaft
and likewise diametrically enlarged with respect to the
hydraulic-fluid adapter--as the axial bearing of the camshaft.
[0006] Alternatively, it is also possible to form the part of the
axial bearing of the camshaft by the washer through a spacing ring
fashioned on the axial side of the camshaft-coupled component
facing away from the camshaft or through another diametrically
expanded end flange positioned on the end wall of the
hydraulic-fluid adapter facing the camshaft.
[0007] In appropriately refining this device according to the
present invention, it is still further proposed that one can
additionally position the head of the axial fastening bolt of the
device at least partially in a countersink in the end wall of the
hydraulic-fluid adapter facing away from the camshaft in order to
still further reduce the overall axial length of the camshaft
designed with the device. Proving especially advantageous here is
the use of a fastening bolt having a hexagonal-socket-head which
includes a diametrically enlarged collar and is positioned over
about half of its axial length in the countersink of the
hydraulic-fluid adapter.
[0008] The impulse-sending wheel formed by the end flange on the
hydraulic-fluid adapter is designed in this case as a flat
ring-shaped disk whose impulse marks are formed by notches or
boreholes or the like distributed symmetrically or asymmetrically
around its periphery or on its axial side and which cooperates with
an impulse-reading device secured to the internal combustion engine
and positioned axially to it.
[0009] It is also possible to solve the problem lying at the basis
of the present invention involving a device for changing the timing
of intake and exhaust valves by providing the impulse-sending wheel
of the device attached to the end wall of the hydraulic-fluid
adapter facing away from the camshaft with a greater diameter than
the hydraulic-fluid adapter and--together with a washer positioned
between the adapter and the camshaft-coupled component and likewise
diametrically enlarged with respect to the hydraulic-fluid
adapter--is simultaneously designed as the axial bearing for the
camshaft.
[0010] In this case, it is also alternatively possible to form the
part of the axial bearing of the camshaft formed by the washer
through a spacing ring fashioned on the axial side of the
camshaft-coupled component facing away from the camshaft or through
a diametrically enlarged end flange positioned on the
camshaft-facing end wall of the hydraulic-fluid adapter, as in the
above-described embodiment.
[0011] As an appropriate refinement of the device according to the
present invention, it is also possible to provide the
impulse-sending wheel preferably as a cup-shaped sheet-metal piece
which is separately attached by an additional nut to the head of
the axial fastening bolt of the device such that it radially
surrounds this nut. This special attachment of the impulse-sending
wheel to the device has proven to be especially advantageous with
regard to its consequently possible separate adjustability during
assembly of the device to the camshaft of the internal combustion
engine since then, with initially only lightly tightened fastening
bolt, the required starting position of the camshaft-coupled
component or the camshaft to the crankshaft-coupled component or
the crankshaft can be adjusted and subsequently, with fully
tightened fastening bolt, the impulse-sending wheel can be
separately suitably adjusted. However, it would also be possible to
secure the impulse-sending wheel to the hydraulic-fluid adapter
with the axial fastening bolt of the device and to carry out
simultaneously the adjustment of the camshaft-coupled component
with respect to the crankshaft-coupled component of the device as
well as the adjustment of the impulse-sending wheel. In the same
way, it is also possible with the device according to the present
invention to design the impulse-sending wheel as a flat ring-shaped
disk and/or to position the head of the axial fastening bolt at
least partially in a countersink in the hydraulic-fluid adapter in
order to reduce the overall axial length of the camshaft designed
with the device.
[0012] The preferably cup-shaped impulse-sending wheel of this
device is provided as part of the axial bearing of the camshaft,
which can also be fashioned with the same arrangement and action
like a spoked wheel with angled spoke ends on the peripheral side,
and furthermore includes at its periphery symmetrically or
unsymmetrically distributed impulse marks designed as notches,
boreholes, or the like and cooperates in this case with an
impulse-reading device secured to the internal combustion engine
and positioned radially to it.
[0013] Both of the devices according to the present invention thus
exhibit, compared to the device known from the state of the art,
the advantage that as a result of the integration of the axial
bearing of the camshaft or the axial bearing of the camshaft and
the impulse-sending wheel of the device in the components present
in the device, it is no longer necessary to provide a special axial
bearing for the camshaft. As a result, the production costs of a
camshaft provided with such a device are considerably reduced in
advantageous fashion. At the same time, the overall axial length of
camshafts provided with these devices is reduced such that the
devices of the present invention can also be used in internal
combustion engines with very restricted space conditions in the
engine compartment of the motor vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention is described in more detail below on
the basis of two preferred embodiments. In the drawings:
[0015] FIG. 1 is a top view of first device according to the
present invention, the device being attached to a camshaft
supported in the cylinder head of an internal combustion
engine;
[0016] FIG. 2 is a top view of a second device according to the
present invention, the device being attached to a camshaft
supported in the cylinder head of an internal combustion
engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] FIGS. 1 and 2 show in each case the schematic representation
of a device 1 for changing the timing of intake and exhaust valves
in an internal combustion engine. The device is attached via an
axial fastening bolt 2 to the drive-side end 3 of a camshaft 5
supported in the cylinder head 4 of the internal combustion engine
and is designed essentially as a hydraulic servo-drive. Moreover,
it is indicated in FIGS. 1 and 2 that device 1 includes a component
6 driven together with an unshown crankshaft of the internal
combustion engine and coupled therewith and a camshaft-coupled
component 7 rotationally secured with the camshaft 5 and
hydraulically rotatable and lockable with respect to the
crankshaft-coupled component 6 and thus capable of effecting a
relative rotation or hydraulic clamping of the camshaft 5 with
respect to the crankshaft. The supply and withdrawal of hydraulic
fluid to and from the device 1 proceeds here via a cylindrical
hydraulic-fluid adapter 9,9' positioned on the device's axial side
8 facing away from the camshaft and attached to the
camshaft-coupled component 7. The adapter includes several
hydraulic-fluid lines 10, 11, 12 running in the axial, in the
radial, and in the circumferential direction, and is supported in a
sleeve bearing 13 in the cylinder head 4 of the internal combustion
engine, which bearing is connected with the hydraulic-fluid circuit
and is designed at the same time as the radial bearing of the
camshaft 5. In addition, as is indicated in each of the figures,
the device 1 includes on the end wall 14 of the hydraulic-fluid
adapter 9,9' facing away from the camshaft, an impulse-sending
wheel 15,15' positioned axially to the camshaft 5, which wheel
cooperates during operation of the internal combustion engine with
an unshown impulse reading unit in determining the camshaft
position with respect to the crankshaft position.
[0018] In order to lower the high production costs for a separate
axial bearing for the camshaft 5 and in order simultaneously to
reduce the overall axial length of the camshaft 5 designed with the
device 1, the hydraulic-fluid adapter 9 of the device 1 shown in
FIG. 1 includes according to the present invention on its end wall
14 facing away from the camshaft a diametrically expanded end
flange 16 which, on the one hand, simultaneously forms the
impulse-sending wheel 15 of device 1 and, on the other hand, is
designed--together with a washer 17 positioned between the
hydraulic-fluid adapter 9 and the camshaft-coupled component 7 and
likewise diametrically enlarged with respect to the hydraulic-fluid
adapter 9--as the axial bearing of camshaft 5. As is clearly
recognizable from FIG. 1, the head 18 of axial fastening bolt 2 of
device 1 is additionally partially positioned here in a countersink
19 in the end wall 14 of the hydraulic-fluid adapter 9 facing away
from the camshaft in order to further reduce the overall axial
length of the camshaft 5 used with the device.
[0019] In the case of the device 1 shown in FIG. 2, in contrast,
the impulse-sending wheel 15' positioned on the end wall 14 of
hydraulic-fluid adapter 9' facing away from the camshaft includes
according to the present invention a larger diameter than the
hydraulic-fluid adapter 9' which in reduce the production costs
associated with a separate axial bearing for camshaft 5 so that it
is designed--together with a washer 17 likewise positioned between
the adapter and the camshaft-coupled component 7 and likewise
diametrically enlarged with respect to the hydraulic-fluid adapter
9'--as the axial bearing of camshaft 5. The impulse-sending wheel
15' is provided here, as is clear from FIG. 2, as a cup-shaped
sheet-metal part which is separately attached by an additional nut
20 to the head 18 of the axial fastening bolt 2 of device 1 and
radially surrounds nut 20.
ELEMENT NUMBERS
[0020] 1 device
[0021] 2 fastening bolt
[0022] 3 drive-side end
[0023] 4 cylinder head
[0024] 5 camshaft
[0025] 6 crankshaft-coupled component
[0026] 7 camshaft-coupled component
[0027] 8 axial side facing away from the camshaft
[0028] 9 hydraulic-fluid adapter
[0029] 9' hydraulic-fluid adapter
[0030] 10 hydraulic-fluid lines
[0031] 11 hydraulic-fluid lines
[0032] 12 hydraulic-fluid lines
[0033] 13 sleeve bearing
[0034] 14 end wall facing away from the camshaft
[0035] 15 impulse-sending wheel
[0036] 15' impulse-sending wheel
[0037] 16 end flange
[0038] 17 washer
[0039] 18 bead
[0040] 19 countersink
[0041] 20 nut
* * * * *