U.S. patent application number 11/003009 was filed with the patent office on 2005-06-02 for device for adjusting the relative angular position of two rotating elements.
Invention is credited to Von Gaisberg-Helfenberg, Alexander.
Application Number | 20050115529 11/003009 |
Document ID | / |
Family ID | 34621235 |
Filed Date | 2005-06-02 |
United States Patent
Application |
20050115529 |
Kind Code |
A1 |
Von Gaisberg-Helfenberg,
Alexander |
June 2, 2005 |
Device for adjusting the relative angular position of two rotating
elements
Abstract
In a device for adjusting the relative angular position of two
rotating elements which are connected to a drive and, via a
transmission element, to an actuating shaft by means of which a
rotor of an electric actuating drive and the relative angular
position of the rotating elements can be changed, the actuating
shaft is operatively connected to at least one of the rotating
elements and normally locked for a safe emergency operating
mode.
Inventors: |
Von Gaisberg-Helfenberg,
Alexander; (Beilstein, DE) |
Correspondence
Address: |
KLAUS J. BACH
4407 TWIN OAKS DRIVE
MURRYSVILLE
PA
15668
US
|
Family ID: |
34621235 |
Appl. No.: |
11/003009 |
Filed: |
December 1, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11003009 |
Dec 1, 2004 |
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PCT/EP03/04105 |
Apr 19, 2003 |
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Current U.S.
Class: |
123/90.17 |
Current CPC
Class: |
F01L 1/46 20130101; F01L
1/344 20130101; F01L 1/34 20130101; F01L 2001/3443 20130101 |
Class at
Publication: |
123/090.17 |
International
Class: |
F01L 001/34 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 1, 2002 |
DE |
102 24 446.4 |
Claims
What is claimed is:
1. A device for adjusting the relative angular position of two
rotating elements (1, 2) interconnected by a transmission element
(3) and connected to a drive structure, including: and electric
actuating drive (5), an actuating shaft (4) extending between the
transmission element (3) and the electric actuating drive (5), a
rotor (5a) connected to the actuating shaft (4) for operating the
actuating shaft (4) in order to change the relative angular
position of the rotating elements (1, 2) and means for operatively
engaging the actuating shaft (4) with at least one of the rotating
elements (1, 2).
2. A device as claimed in claim 1, wherein the relative angular
position of the two rotating elements (1, 2) remains essentially
constant as a result of the operating engagement of the actuating
shaft (4) with one of the rotating elements (1, 2).
3. A device as claimed in claim 1, wherein the operative engagement
between the actuating shaft (4) and one of the rotating elements
(1, 2) is established by the rotor (5a) of the actuating drive
(5).
4. A device as claimed in claim 3, wherein, when the actuating
drive (5) is de-energized its rotor (5a) is operatively engaged
with at least one of the rotating elements (1, 2).
5. A device as claimed in claim 3, wherein the operative engagement
between the rotor (5a) and rotating element (1, 2) is established
by an application of an axial force (F.sub.A1) to the rotor
(5a).
6. A device as claimed in claim 3, wherein the operative engagement
is released upon energization of the actuating drive (5).
7. The device as claimed in claim 3, wherein, upon energization of
the actuating drive (5), an axial force (F.sub.A2) is active
between a stator (5b) and the rotor (5a) of the actuating drive
(5).
8. The device as claimed in claim 7, wherein the effect of the
axial force (F.sub.A2) between the stator (5b) and rotor (5b) is
caused by an axial offset (7) between the stator (5b) and rotor
(5a).
9. The device as claimed in claim 1, wherein the rotor (5a) of the
electric actuating drive (5) is mounted on one of the rotating
elements (1, 2).
10. The device as claimed in claim 1, wherein the rotor (5a) of the
electric actuating drive (5) is directly connected to an actuating
shaft (4).
11. The device as claimed in claim 1, wherein the operative
connection between the actuating shaft (4) and the rotating element
(1, 2) is established by a component which can be actuated
separately.
12. The device as claimed in claim 11, wherein the component which
can be actuated separately establishes one of a frictionally
locking, a positively locking and a non-positively locking
engagement.
13. The device as claimed in claim 1, wherein the operative
connection is established by frictional engagement.
Description
[0001] This is a Continuation-In-Part Application PCT/EP03/04105
filed Apr. 19, 2003 and claiming the priority of German application
102 24 446.4 filed Jun. 1, 2002.
BACKGROUND OF THE INVENTION
[0002] The invention related to a device for adjusting a relative
angular position of two rotating elements which are connected to a
drive by a transmission element.
[0003] Devices of this type are used for example in internal
combustion engines and are provided there for effecting a relative
angular adjustment of the camshaft with respect to the crank-shaft
driving the camshaft. The adjustments in the kinematics of the
valve drive influences within limits the phase angle of the valve
opening, the opening period and the valve stroke in a variable
fashion.
[0004] DE 100 36 375 A1 discloses such a device for effecting a
relative angular adjustment between a camshaft and a crank-shaft of
an internal combustion engine. A chain wheel is mounted on the
camshaft so as to be driven by the crankshaft, the chain wheel
driving the camshaft via a transmission element. The transmission
element makes it possible to change the relative angular position
of the two rotating elements, that is, the chain wheel and the
camshaft. This change is brought about by an electric actuating
drive whose rotor acts on an actuating shaft of the transmission
element and which also rotates in each operating state of the
drive.
[0005] When inertia forces which are triggered by oscillations act
on the rotor of the actuating element or the actuating shaft of the
transmission element, undesired adjustments of the relative angular
position may take place. This has to be compensated for by the
actuating drive and requires a continuous application of energy.
When the actuating drive fails, this function is no longer
effective and uncontrolled adjustments occur which may make the
operation of the internal combustion engine difficult and possibly
damage the internal combustion engine. Since the actuating drive
must also continuously rotate, it may also heat up during normal
operation in an unacceptable way. In such a case, the internal
combustion engine would have to be shut down in order to prevent
damage to the actuating drive.
[0006] With respect to the general technical background, reference
is made also to DE 100 38 354 A1 and DE 41 10 195 A1.
[0007] It is the object of the present invention to provide a
device in which the actuating drive has a low electrical energy
consumption and the device has a reliable emergency operating
mode.
SUMMARY OF THE INVENTION
[0008] In a device for adjusting the relative angular position of
two rotating elements which are connected to a drive and, via a
transmission element, to an actuating shaft by means of which a
rotor of an electric actuating drive and the relative angular
position of the rotating elements can be changed, the actuating
shaft is operatively connected to at least one of the rotating
elements and normally locked for a safe emergency operating
mode.
[0009] A significant advantage of the invention is that during
normal operation, the transmission element can be blocked in a set
relative angular position of the two rotating elements and the
actuating drive does not require any energy to maintain this
setting. This leads to an overall lower energy consumption and thus
to a lower application of heat to the actuating drive. If,
nevertheless, inadmissible heating of the actuating drive should
occur, it can be deactivated for the purpose of cooling when the
internal combustion engine is operating without uncontrolled
adjustment of the relative angular position of the two rotating
elements.
[0010] In one particular embodiment of the invention, in which the
rotor of the actuating drive is operatively connected to at least
one of the rotating elements in the state in which the actuating
drive is not energized, the transmission element is blocked
automatically when the actuating drive fails, thus ensuring a set
emergency operating mode.
[0011] The invention will become more readily apparent from the
following description of a preferred embodiment thereof on the
basis of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0012] The sole FIGURE is a schematic, partially sectional,
illustration showing a detail of a camshaft drive of an internal
combustion engine with a device according to the invention.
DESCRIPTION OF A PREFERRED EMBODIMENT
[0013] In the schematic illustration of the camshaft drive of an
internal combustion engine, a rotating element which is embodied as
a camshaft is designated by the reference numeral 1. A further
rotating element 2, which is embodied as a chain wheel, is mounted
on the rotating element 1 in the drive structure of a crankshaft of
the internal combustion engine. The chain wheel 2 drives the
camshaft 1 via a transmission element 3 so that the camshaft 1 and
the chain wheel 2 have the same rotational speed. The chain wheel 2
which is fitted with a chain on its circumference is arranged
concentrically with respect to the camshaft 1 and rotatably
supported thereon, the transmission element 3 being located
operatively between the camshaft 1 and the chain wheel 2. The
transmission element 3 (not illustrated in detail) may be embodied,
for example, as a planetary gear mechanism, a swash plate mechanism
or the like and has an actuating shaft 4 which is acted on by a
rotor 5a of an electric actuating drive 5. The drive torque which
is necessary for the position adjustment is generated between the
rotor 5a and a stator 5b of the actuating drive 5.
[0014] By means of a relative rotation of the actuating drive 4,
the relative angular position of the two rotating elements 1, 2
with respect to one another can be changed. The relative rotation
of the actuating shaft 4 is brought about by means of the rotor 5a
of the actuating drive 5.
[0015] In order to bring about low energy consumption and a
reliable emergency operating function, the actuating shaft 4 can,
according to the invention, be operatively connected to one of the
camshaft 1 and the chain gear 2, the operative connection between
the actuating shaft 4 and the chain gear 2 being illustrated in the
exemplary embodiment. The operative connection between the
actuating shaft 4 and the chain gear 2 is established by means of
the rotor 5a of the actuating drive 5, which is connected to the
actuating shaft 4 in an axially displaceable fashion. The operative
connection of the actuating shaft 4 to the chain gear 2 causes the
transmission element 3 to be blocked, as a result of which the
relative angular position bof the camshaft 1 and the chain gear 2
remains constant.
[0016] When the actuating drive 5 is not energized, the rotor 5a is
operatively connected to the chain gear 2. The operative connection
between the rotor 5a and chain gear 2 is made by means of an
application of an axial force F.sub.A1 to the rotor 5a, the force
being generated by a disc spring 6. Other devices can also be used
to generate the axial force F.sub.A1.
[0017] Only when the actuating drive is energized, the operative
connection between the rotor 5a and chain gear 2 is released in
order to keep the electrical drive power of the actuating drive 5
low. When the actuating drive 5 is energized, an axial force
component F.sub.A2 is advantageously established between the stator
5b and rotor 5a of the actuating drive 5. Such a force may be
generated, for example, by means of an axial offset 7 between the
stator 5b and rotor 5a since, as a result of such an offset 7, such
an axial force component F.sub.A2 is provided.
[0018] In the arrangement shown in the FIGURE the rotor 5a is not
mounted rotatably on the housing, but on the rotating element 1
thus avoiding friction losses, it being also conceivable to mount
it on another rotating element, for example, the actuating shaft
4.
[0019] The operative connection between the actuating shaft 4 and
one of the rotating elements 1, 2 can also be effected by means of
a component (not illustrated here) which can be actuated
separately. The component may be embodied as a frictionally locking
connecting element such as a brake structure and/or a
non-positively locking connecting element such as a clutch and/or a
positively locking connecting element such as a magnetic
clutch.
[0020] Each of the operative connecting possibilities described
above can advantageously be carried out in a frictionally locking
fashion.
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