U.S. patent application number 12/800552 was filed with the patent office on 2010-12-02 for vane-type camshaft adjuster system.
This patent application is currently assigned to Hydraulik-Ring GmbH. Invention is credited to Marius Cornea, Matthias Lang.
Application Number | 20100300388 12/800552 |
Document ID | / |
Family ID | 43049095 |
Filed Date | 2010-12-02 |
United States Patent
Application |
20100300388 |
Kind Code |
A1 |
Lang; Matthias ; et
al. |
December 2, 2010 |
Vane-type camshaft adjuster system
Abstract
The object of the invention is to provide an economical
vane-type camshaft adjuster system that meets the various
requirements of various motors. For this purpose, according to the
invention a modular system is provided for the valves of a
vane-type camshaft adjuster system. Two different embodiments of
valves are proposed. With one embodiment, a valve with mid-locking
and without mid-locking may be constructed using the same bush.
With the other embodiment, a valve with and without special
utilization of the camshaft alternating torques may be constructed
using the same bush.
Inventors: |
Lang; Matthias; (Roden,
DE) ; Cornea; Marius; (Lohr am Main, DE) |
Correspondence
Address: |
Lipsitz & McAllister, LLC
755 MAIN STREET
MONROE
CT
06468
US
|
Assignee: |
Hydraulik-Ring GmbH
Marktheidenfeld
DE
|
Family ID: |
43049095 |
Appl. No.: |
12/800552 |
Filed: |
May 17, 2010 |
Current U.S.
Class: |
123/90.17 |
Current CPC
Class: |
F01L 2820/01 20130101;
F01L 1/3442 20130101; F01L 2001/34426 20130101; F01L 2001/34463
20130101; F01L 2001/34469 20130101 |
Class at
Publication: |
123/90.17 |
International
Class: |
F01L 1/34 20060101
F01L001/34 |
Foreign Application Data
Date |
Code |
Application Number |
May 27, 2009 |
DE |
10 2009 022 869 |
Claims
1. Vane-type camshaft adjuster system for a drive motor,
comprising: a rotor having at least one vane that divides a
pressure chamber formed circumferentially between two radially
inwardly directed webs of a stator into two hydraulic chambers
working in opposite directions, a locking pin associated with said
pressure chamber, which locking pin is aligned parallel to a
central axis and which in a locking position fixes the rotor
relative to the stator in an intermediate position lying between
"early" and "late" end positions, an electrohydraulic 4/4-way valve
for controlling the two hydraulic chambers, the 4/4-way valve
comprising: a supply port (P), a first working port (A) for the
first hydraulic chamber, a second working port (B) for the second
hydraulic chamber, and a tank port (T), by means of the 4/4-way
valve in a first position (1) during disconnection, stopping or
starting of the drive motor through simultaneous hydraulic
interconnection of the two working ports (A, B), the two hydraulic
chambers being relieved to an unpressurized state relative to the
tank port (T) so that the locking pin moves into the locking
position, the 4/4-way valve being of a cartridge style of
construction and comprising a bush, which is provided with three
openings disposed axially adjacent to one another and inside which
a hollow piston is axially displaceable along a running surface,
and a cup base which is provided at the magnet-side piston end,
which cup base is supported under spring loading against a
displaceable tappet of a magnet part, the piston comprising: two
circumferential annular control grooves, an outflow recess at the
magnet-side piston end leading to the tank port (T) and aligned
transversely of the central axis, and a circumferential outer web
adjacent to said outflow recess, past which a hydraulic flow may be
conveyed from the second working port (B) to the outflow recess,
said circumferential outer web at the spring-side piston end takes
the form of a circumferential control edge for directing hydraulic
fluid to the tank port (T).
2. Vane-type camshaft adjuster system according to claim 1, wherein
an inner running surface of the bush is drilled in one diameter in
a region of the openings associated with the two working ports (A,
B).
3. Vane-type camshaft adjuster system according to claim 2, wherein
an inside diameter of the bush in an axial region between the
magnet part and the outer web positioned closest thereto is
designed with an inside diameter that is widened relative to the
running surface.
4. Vane-type camshaft adjuster system according to claim 1, wherein
the recess associated with the supply port (P) is provided axially
between the openings associated with the working ports (A, B).
5. Vane-type camshaft adjuster system for a drive motor,
comprising: a rotor having at least one vane that divides a
pressure chamber formed circumferentially between two radially
inwardly directed webs of a stator into two hydraulic chambers
working in opposite directions, an electrohydraulic 4/4-way valve
for controlling the two hydraulic chambers, the 4/4-way valve
comprising: a first working port (A) for the first hydraulic
chamber, a second working port (B) for the second hydraulic
chamber, a supply port (P) disposed in relation to a central axis
between said two working ports (A, B), and a tank port (T), the
4/4-way valve being of a cartridge style of construction and
comprising a bush, which is provided with at least four openings
disposed axially adjacent to one another, of which a first and a
second opening are associated with the one of the two working ports
(B and/or A), of which the first opening positioned closer to the
supply port (P) is provided with a non-return valve, by means of
which hydraulic fluid is directed from the first hydraulic chamber
associated with said one working port (B and/or A) through the
other working port (A and/or B) to the second hydraulic chamber
associated with said other working port (A and/or B) when: the
second opening is closed by a hollow piston, and camshaft
alternating torques raise the hydraulic pressure in the first
hydraulic chamber above the hydraulic pressure inside the bush,
inside said bush the piston being axially displaceable along a
running surface and at the magnet-side piston end a cup base is
provided, which is supported under spring loading against a
displaceable tappet of a magnet part, wherein the piston comprises:
at least one circumferential annular control groove, an outflow
recess at the magnet-side piston end leading to the tank port (T)
and aligned transversely of the central axis, and a circumferential
outer web adjacent to said outflow recess, past which a hydraulic
flow may be conveyed from the spring-side working port (B) to the
outflow recess, said circumferential outer web at the spring-side
piston end takes the form of a circumferential control edge for
directing hydraulic fluid to the tank port (T).
6. Vane-type camshaft adjuster system according to claim 5, wherein
an inner running surface of the bush is drilled in one diameter in
a region of the openings associated with the two working ports (A,
B).
7. Vane-type camshaft adjuster system according to claim 6, wherein
an inside diameter of the bush in an axial region between the
magnet part and the outer web positioned closest thereto is
designed with an inside diameter that is widened relative to the
running surface.
8. Vane-type camshaft adjuster system according to claim 5, wherein
the recess associated with the supply port (P) is provided axially
between the openings associated with the working ports (A, B).
9. Set of valves for a vane-type camshaft adjuster system for a
drive motor, comprising: at least two types of valves, each valve
comprising: a first working port (A) for a first hydraulic chamber,
a second working port (B) for a second hydraulic chamber, a supply
port (P), and a tank port (T), an identical magnet part, an
identical bush, and one of a piston with mid-locking and a piston
without mid-locking, wherein: the piston with mid-locking
comprises: two circumferential annular control grooves, an outflow
recess at a magnet-side piston end leading to the tank port (T) and
aligned transversely of a central axis, and a circumferential outer
web adjacent to said outflow recess, past which a hydraulic flow
may be conveyed from the second working port (B) to the outflow
recess, said circumferential outer web at a spring-side piston end
takes the form of a circumferential control edge for directing
hydraulic fluid to the tank port (T); and the piston without
mid-locking comprises: at least one circumferential annular control
groove, an outflow recess at a magnet-side piston end leading to
the tank port (T) and aligned transversely of the central axis, and
a circumferential outer web adjacent to said outflow recess, past
which a hydraulic flow may be conveyed from a spring-side working
port (B) to the outflow recess, said circumferential outer web at
the spring-side piston end takes the form of a circumferential
control edge for directing hydraulic fluid to the tank port
(T).
10. A set of valves according to claim 9, further comprising: at
least one rotor having at least one vane that divides a pressure
chamber formed circumferentially between two radially inwardly
directed webs of a stator into the two hydraulic chambers working
in opposite directions.
11. A set of valves according to claim 9, wherein the valve with
the mid-locking piston further comprises: a locking pin associated
with said pressure chamber, which locking pin is aligned parallel
to a central axis and which in a locking position fixes the rotor
relative to the stator in an intermediate position lying between
"early" and "late" end positions; and wherein by means of the valve
in a first position (1) during disconnection, stopping or starting
of the drive motor through simultaneous hydraulic interconnection
of the two working ports (A, B), the two hydraulic chambers being
relieved to an unpressurized state relative to the tank port (T) so
that the locking pin moves into the locking position.
12. A set of valves according to claim 9, wherein: each bush is
provided with at least three openings disposed axially adjacent to
one another and inside which the piston is axially displaceable
along a running surface, and a cup base is provided at the
magnet-side piston end, which cup base is supported under spring
loading.
13. A set of valves according to claim 12, wherein, in the valve
with the piston without mid-locking, camshaft alternating torques
raise the hydraulic pressure in the first hydraulic chamber above
the hydraulic pressure inside the bush.
Description
[0001] This application claims the benefit of German patent
application no. DE 10 2009 022 869.1 filed on May 27, 2009, which
is incorporated herein and made a part hereof by reference for all
purposes.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a vane-type camshaft adjuster
system.
[0003] From DE 10 2004 039 800 B4 a vane-type camshaft adjuster
system for a drive motor is already known. Such a vane-type
camshaft adjuster comprises a rotor having five vanes, which are
disposed circumferentially between radially inwardly directed webs
of a stator. The vanes divide in each case one pressure chamber
into two hydraulic chambers working in opposite directions. One
pressure chamber of these five pressure chambers has a
spring-loaded locking pin, which is aligned parallel to a central
axis. When this locking pin is situated in a locking position, the
rotor is then fixed relative to the stator in an intermediate
position lying between "early" and "late" end positions.
[0004] Locking in such an intermediate position that is neither the
"early" end position nor the "late" end position is generally also
referred to as mid-locking even if this mid-locking is not effected
exactly mid-way between the two end positions.
[0005] The two hydraulic chambers of the vane-type camshaft
adjuster according to DE 10 2004 039 800 B4 are controllable by
means of an electrohydraulic 4/4-way valve having a magnet part as
an actuator. For this purpose the valve has: [0006] a first working
port A for the first hydraulic chamber, [0007] a second working
port B for the second hydraulic chamber, [0008] a tank port T and
[0009] a supply port P.
[0010] Upon starting of the drive motor, by means of the 4/4-way
valve in a first state through simultaneous interconnection of the
two working ports the two hydraulic chambers are relieved to an
unpressurized state relative to the tank port T. In this
unpressurized state the locking pin may move into the locking
position. The 4/4-way valve in this case is of a cartridge style of
construction. It comprises a bush, inside which a hollow piston is
guided in an axially displaceable manner. For this purpose the
piston has at the one end a cup base, which is supported under
spring loading against an electromagnetically displaceable tappet
of the magnet part. The bush has three recesses disposed axially
adjacent to one another. The piston on the other hand has
circumferential annular control grooves. By displacing the axial
position of the annular control grooves relative to the three
recesses, a hydraulic fluid coming from the supply port P is
conveyed towards the two working ports A, B and/or towards the tank
port T.
[0011] DE 103 44 816 B4 relates to a further vane-type camshaft
adjuster system for a drive motor. This reference discloses a
cartridge-style 6/4-way valve which likewise comprises a bush and a
piston disposed inside the bush. The 6/4-way valve has a separate
position for removing hydraulic fluid from the two hydraulic
chambers so that two spring-loaded locking devices may lock in an
intermediate position that is neither the "early" end position nor
the "late" end position. These two locking devices are radially
aligned and disposed in a web of the stator. One of the three ports
of the 6/4-way valve is associated exclusively with the two locking
devices.
[0012] From DE 10 2006 012 733 B4 and/or DE 10 2006 012 775 B4 a
vane-type camshaft adjuster system having a 4/3-way valve is known.
This valve is of a cartridge style of construction. Inserted into
the bush at the inside are non-return valves that take the form of
band-shaped rings. By means of these non-return valves, camshaft
alternating torques are utilized to allow the camshaft adjuster to
be adjusted particularly quickly and/or with a relatively low oil
pressure.
[0013] From DE 44 22 742 C2 an electrohydraulic valve is already
known, which comprises: [0014] a supply port P, [0015] a first
working port A, [0016] a second working port B and [0017] a tank
port T.
[0018] The valve is of a cartridge style of construction and
comprises a bush having three recesses. Inside the bush a hollow
piston is axially displaceable along a running surface. For this
purpose there is provided at one piston end a cup base, which is
supported under spring loading against a displaceable tappet of an
electromagnetic actuator. The piston has a circumferential annular
control groove. Provided at the two piston ends are outflow
recesses, which are aligned transversely of a central axis of the
valve and lead to the tank port T. Provided on the piston, adjacent
to the magnet-side outflow recess, is a circumferential rib, past
which a hydraulic flow may be conveyed from the magnet-side working
port to the outflow recess.
[0019] The object of the invention is to provide an economical
vane-type camshaft adjuster system that meets the various
requirements of various motors.
[0020] This and other objects are achieved according to the present
invention.
SUMMARY OF THE INVENTION
[0021] The present invention provides a modular system for the
valves of a vane-type camshaft adjuster system. Two different
embodiments of valves are proposed. With one example embodiment, a
valve with mid-locking and without mid-locking may be constructed
using the same bush. With another example embodiment, a valve with
and without special utilization of the camshaft alternating torques
may be constructed using the same bush.
[0022] According to the present invention, one example embodiment
of a valve of the vane-type camshaft adjuster system is disclosed,
which enables mid-locking with an economical valve. The valve may
have details developed in a constructionally identical manner for a
vane-type camshaft adjuster system with utilization of the camshaft
alternating torques.
[0023] According to one advantageous aspect of the invention, it is
at the piston end facing the magnet part (i.e. the magnet-side
piston end) that an outflow recess leading to the tank port T and
aligned transversely relative to the central axis is provided. On
the other hand, the other end is designed as a piston-terminating
control edge for directing hydraulic fluid to the tank port T.
This, on the one hand, achieves cost benefits as the piston
therefore has to be provided with relatively few recesses--in
particular transverse bores. The piston may also be of a relatively
short design, thereby allowing a saving of material not only at the
piston but also at the bush. Furthermore, a helical compression
spring for spring-loading the piston towards a tappet of the magnet
part may be of a relatively short design as this helical
compression spring may be supported relatively close to the piston
end. The short overall length of the 4/4-way valve also offers
advantages in terms of installation space.
[0024] In a further advantageous manner the bush and the piston
according to the present invention are designed in such a way that
it is possible to create a design family of valves for vane-type
camshaft adjusters that enables only slight design variations
between the valves. These valves may be: [0025] a 4/4-way valve
with a special outflow position for the mid-locking, but without
non-return valves for special utilization of the camshaft
alternating torques; [0026] a 4/4-way valve with a special outflow
position for the mid-locking and with non-return valves for special
utilization of the camshaft alternating torques; [0027] a 4/3-way
valve without a special outflow position for the mid-locking and
with non-return valves for special utilization of the camshaft
alternating torques; and [0028] a 4/3-way valve without a special
outflow position for the mid-locking and without non-return valves
for special utilization of the camshaft alternating torques.
[0029] In particular the magnet parts of such valves be of an
identical design. The pistons of a valve without mid-locking need
differ from the pistons with mid-locking only in that in the more
complex variant with mid-locking: [0030] on the one hand a middle
outer web is provided, which divides the annular groove into two
annular grooves, and [0031] on the other hand a magnet-side outer
web is divided by means of an annular groove into two outer
webs.
[0032] For the constructional realization, there is provided on the
piston, adjacent to the outflow recess, a circumferential rib, past
which a hydraulic flow coming from the magnet-side working port B
may be conveyed to the outflow recess. Furthermore, between the
magnet part and the second working port B, a region having an
inside diameter that is widened relative to the running surface is
provided, thereby forming between this inside diameter and the
running surface a run-off edge that is blockable by the rib. Thus,
by virtue of the fact that a circumferential rib always forms the
run-off edge relative to the recess of the working port B, the
piston need not be installed angularly oriented relative to the
bush. For this reason, it is also possible to dispense with an
anti-rotation element between the bush and the piston and hence
reduce costs. If, however, the outflow recess were directly to form
the run-off edge relative to the recess of the second working port
B, an expensive angular orientation would be necessary. The
solution according to the invention comprising a circumferential
rib for blocking/releasing of the outflow recess to the piston, on
the other hand, makes it possible to allow the piston to run
directly along the running surface that is penetrated by the recess
for the working port B. The same applies to the embodiment (as
described in the previous paragraph) of the other piston end as a
control edge. This spring-side piston end may also slide directly
along the running surface in the region of the recess which
penetrates this running surface of the first working port A, with
the result, at this piston end too, that the piston requires no
angular orientation and/or anti-rotation element. The running
surface may therefore inexpensively take the form of a bore passing
through the entire running region. The internal machining of the
running surface may in this case be carried out by a high-quality
surface treatment.
[0033] In this case, in an advantageous manner the inside diameter
of the bush in the axial region between the magnet part and the
outer web positioned closest thereto may be designed with an inside
diameter that is widened relative to the running surface. For the
external machining of the bush it is therefore possible to clamp
the bush tightly in a tool, for example a three-jaw chuck, without
the bush being plastically deformed to such an extent that the
running surface becomes inoperative.
[0034] Further advantages of the invention emerge from the claims,
the detailed description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The present invention will hereinafter be described in
conjunction with the appended drawing figures, wherein like
reference numerals denote like elements, and:
[0036] FIG. 1 shows an example embodiment of a vane-type camshaft
adjuster in accordance with the present invention,
[0037] FIG. 2 shows a sectional representation of a 4/4-way valve
in a first example embodiment of the present invention,
[0038] FIG. 3 a sectional representation of the hydraulic part
along line II-II of FIG. 1,
[0039] FIG. 4 a hydraulic diagram of the 4/4-way valve of FIG. 2
and FIG. 3,
[0040] FIG. 5 shows the hydraulic part of the valve of FIG. 2 in a
first position,
[0041] FIG. 6 shows the hydraulic part according to FIG. 5 in a
second position,
[0042] FIG. 7 shows the hydraulic part in a third position,
[0043] FIG. 8 shows the hydraulic part in a fourth position,
[0044] FIG. 9 shows the piston of the 4/4-way valve of FIG. 2 to
FIG. 8 as a single part in a perspective view,
[0045] FIG. 10 shows another piston for a valve of a vane-type
camshaft adjuster system in a second example embodiment of the
present invention,
[0046] FIG. 11 shows a 4/3-way valve having the piston according to
FIG. 10,
[0047] FIG. 12 shows a sectional representation of the hydraulic
part of the 4/3-way valve along line XII-XII of FIG. 11,
[0048] FIG. 13 shows a hydraulic diagram of the 4/3-way valve of
FIG. 11 and FIG. 12,
[0049] FIG. 14 to FIG. 16 show, in views similar to that of FIGS.
2-4, a third example embodiment of a hydraulic part for an
electrohydraulic 4/4-way valve of a vane-type camshaft adjuster
system in accordance with the present invention, and
[0050] FIG. 17, FIG. 18 and FIG. 19 show, in views similar to that
of FIGS. 2-4, a fourth example embodiment of a the hydraulic part
for an electrohydraulic 4/3-way valve of a vane-type camshaft
adjuster system in accordance with the present invention.
DETAILED DESCRIPTION
[0051] The ensuing detailed description provides exemplary
embodiments only, and is not intended to limit the scope,
applicability, or configuration of the invention. Rather, the
ensuing detailed description of the exemplary embodiments will
provide those skilled in the art with an enabling description for
implementing an embodiment of the invention. It should be
understood that various changes may be made in the function and
arrangement of elements without departing from the spirit and scope
of the invention as set forth in the appended claims.
[0052] In accordance with an example embodiment of the present
invention as shown in FIG. 1, by means of a vane-type camshaft
adjuster during operation of a combustion-engine drive motor the
angular position between a crankshaft, which is not represented in
detail, and a camshaft 127 is varied. In this case, by rotating the
camshaft 127 the opening and closing times of the gas exchange
valves are shifted in such a way that the combustion-engine drive
motor produces its optimum output and/or best possible exhaust gas
emissions for the respective rotational speed. The vane-type
camshaft adjuster in this case enables a stepless adjustment of the
camshaft 127 relative to the crankshaft. The vane-type camshaft
adjuster has a cylindrical stator 101, which is connected in a
rotationally fixed manner to a gearwheel, which is not represented
in detail. This gearwheel may be for example a sprocket wheel, over
which a chain extends. The gearwheel may however alternatively be a
toothed-belt wheel, over which a drive belt extends as a drive
element. By means of this drive element and the gearwheel the
stator 101 is in a known manner drive-connected to the
crankshaft.
[0053] The stator 101 comprises a cylindrical stator basic body
103, from the inside of which webs 104 project radially inwards at
uniform intervals over the circumference. Formed between adjacent
webs 104 are pressure chambers 105, into which pressure medium is
introduced. The introduction of this pressure medium is effected in
a controlled and/or regulated manner by means of a 4/4-way valve
and/or 4/3-way valve in accordance with the present invention that
is described below in connection with the figures. Protruding
between adjacent webs 104 are vanes 106, which project radially
outwards from a cylindrical rotor basic body 107 of a rotor 108.
These vanes 106 subdivide the pressure chambers 105 between the
webs 104 in each case into two hydraulic chambers 109 and 110.
[0054] The webs 104 lie with their end faces sealingly against the
outer lateral surface of the rotor basic body 107. The vanes 106 in
turn lie with their end faces sealingly against the cylindrical
inner wall of the stator basic body 103.
[0055] The rotor 108 is connected in a rotationally fixed manner to
the camshaft 127. In order to vary the angular position between the
camshaft 127 and the crankshaft, the rotor 108 is rotated relative
to the stator 101. For this purpose, depending on the desired
direction of rotation the pressure medium in the first hydraulic
chambers 109 and/or 110 is pressurized, while the second hydraulic
chambers 110 and/or 109 are relieved in the direction of the
tank.
[0056] The rotor 108 is positively fixable in a rotationally fixed
manner relative to the stator 101. For this purpose a locking pin
121 is provided, which is aligned parallel to a central axis 125 of
the vane-type camshaft adjuster. This locking pin 121 is preloaded
by a small compression spring and in a locking position of the
rotor 108 relative to the stator 101 may engage into a location
hole 126 of the stator 101. This location hole 126 lies, in terms
of the circumference, in an intermediate position between the
"early" and "late" end positions.
[0057] FIG. 2 shows a partial section of a proportionally
adjustable 4/4-way valve 81, which in this embodiment is used for
the adjustment of the camshaft of a combustion-engine drive motor
having a vane-type camshaft adjuster.
[0058] In this case, the 4/4-way valve 81 takes the form of a
cartridge valve. This cartridge valve comprises a hydraulic part 83
and a magnet part 5. The hydraulic part 83 has a piston 13 and a
bush 15. The piston 13 runs inside the bush 15 along the running
surface 85 thereof. The piston 13 is preloaded by means of a
helical compression spring 9, which is supported relative to a
support ring 11 on the bush 15. The bush 15 is provided with
openings 86, 87, 88, which in the illustrated case are rotationally
symmetrical bores. These openings 86, 87, 88 represent the first
working port A, the second working port B and the supply port P.
The arrows indicate the regular oil directions. At the end face of
the hydraulic part 83 a central opening 17 is provided for the tank
port T. This tank port T lies at right angles to the other three
ports A, B and P of the 4/4-way valve 81. The opening 17 for the
tank port T lies centrally inside the support ring 11. The helical
compression spring 9 encircles this opening 17 for the tank port T.
The piston 13 is hollow. The piston 13 is provided with outflow
recesses 21, which at the magnet-side piston end establish the
connection to the hollow space 89 of the piston 13. In and around
the 4/4-way valve 81 a series of seals are mounted, which during
operation keep the hydraulic fluid away from the environment and
from the parts not supplied with hydraulic fluid. In this case, the
seal 25 as a magnet-part seal seals off the magnet part 5 from the
hydraulic part 83. The tappet 41, which rests against a cup base 93
of the piston 13, is a tappet 41 that is preloaded with hydraulic
fluid and situated in the hydraulic fluid. A pole seal 63 and a
non-visible coil seal ensure that the hydraulic fluid situated in
the magnet part 5 cannot escape outside, i.e. outside of a housing
27. The housing 27 at its side close to the hydraulic part 83
verges into a flange 29 that is provided with fastening openings,
i.e. the fastening bores 31. The pole core 39 succeeding the
hydraulic part 83 is connected by beads 33 to the housing 27. These
beads 33 are disposed in the region of the pole seal 63. Inside the
housing 27 a coil, an armature, the pole core 39 and the tappet 41
are disposed. For further details about the magnet part 5 reference
is made to DE 10 2004 039 800 B4, which in this regard is to be
regarded as incorporated by reference in this application.
[0059] The armature in this case may be moved to and fro between
two armature chambers, which are in fluidic communication with the
hydraulic part 83 of the 4/4-way valve 81 when the piston 13 is
outside of its end stop position.
[0060] On the opposite end of the housing 27 to the opening 17 for
the tank port T an electric plug 47 is fastened.
[0061] A tappet oil space 77 is connected by the outflow recesses
21 to the central opening 17 for the tank port T. This connection
of the hydraulic part 83 to the magnet part 5 of the 4/4-way valve
81 is established by means of an edge-formed portion 23. This
edge-formed portion 23 is attached laterally to the bush 15.
[0062] In the non-energized state of the magnet part 5, the piston
13 blocks off the rear hydraulic channel (coming from armature
chambers) in the magnet part 5 from the tank port T. The helical
compression spring 9 then experiences no counterforce and is in its
outspread, most extended and relaxed position. All of the hydraulic
fluid from the hydraulic chambers 110, 109 of the vane-type
camshaft adjuster escapes through the opening for the tank port T.
Via: [0063] corresponding outer webs 50, 51, 52, 53 on the piston
13, [0064] corresponding inner edges 54, 55 in the bush 15, [0065]
the inner circumferential edges 56, 57 of the openings 88, 86 of
the working ports A, B and [0066] the outflow recess 21, the ports
A and B are in hydraulic communication with the opening 17 for the
tank port T. Placed in front of the openings 86, 87, 88 of the bush
15 are filters 42, 43, 44, which ensure that the 4/4-way valve 81
functions also in the event of contaminated hydraulic fluid.
[0067] The inside diameter of the bush 15 in the axial region
between the magnet part 5 and a shoulder 34 is designed with an
inside diameter that is widened relative to the running surface 85.
This shoulder 34 lies approximately at the outer web 50 positioned
closest to the magnet part 5. For the external machining of the
bush 15 it is therefore possible to clamp the bush 15 tightly in a
three-jaw chuck without the bush 15 being plastically deformed to
such an extent that the running surface 15 becomes inoperative.
[0068] From FIG. 3 it is evident that for producing the four
openings 86 the bush 15 is provided with two bores aligned
orthogonally relative to one another. The same applies to the
openings 87, 88 of the bush 15, which are not visible in FIG.
3.
[0069] FIG. 4 shows the 4/4-way valve 81 in a schematic view. If
the coil of the magnet part 5 is energized with a first, clearly
defined current, the piston 13 moves out of a first position 1 into
a second position 2. If the coil is moreover loaded with a stronger
current and/or a higher duty factor of the pulse width modulation,
the piston 13 moves into the third position 3. Upon an increase to
the strongest defined current, the piston 13 moves into the fourth
position 4. In practice, the positioning of the piston 13 from
position 2 via position 3 to position 4 is not stepped. Instead,
the volumetric flows rise and/or fall in proportion to the current
strength and/or the duty factor.
[0070] FIG. 5 shows, as in FIG. 2 and FIG. 4, the hydraulic part 83
in a first position 1, in which upon disconnection, stopping or
starting of the drive motor through simultaneous hydraulic
interconnection of the two working ports A, B the two hydraulic
chambers 110, 109 are relieved to an unpressurized state relative
to the tank port T, so that the locking pin 121 visible in FIG. 1
moves into the locking position and/or into the location hole 126.
The activation of the coil in this case has such a duty factor that
the piston 13 is displaced by a stroke of between 0 and 0.2 mm
counter to the action of the helical compression spring 9. The
supply port P is closed in the direction of the working ports A, B
by the middle outer web 52 and the outer web 53 disposed on the
spring-side piston end 90. On the other hand, the hydraulic flow
from the working port A along the outer web 53 to the tank port T
is open. In this case, the hydraulic fluid at the spring-side
piston end 90 runs via a circumferential control edge 96 to the
tank port T. The hydraulic flow from the working port B along an
annular groove 91 between the two outer webs 50, 51, which are
positioned close to the magnet part 5, to the tank port T is
likewise open.
[0071] FIG. 6 shows the hydraulic part 83 in the second position 2.
In this case, the activation of the coil has such a duty factor
that the piston 13 is displaced by a stroke of between 0.2 and 0.8
mm counter to the action of the helical compression spring 9. In
this case, the supply port P, starting from a stroke of 0.2 mm,
begins to open for a hydraulic flow to the second working port B.
On the other hand, the hydraulic flow from this second working port
B to the tank port T is closed because the hydraulic pressure is
closed by the outer web 50 positioned closest to the magnet part.
The hydraulic flow from the working port A along the outer web 53
to the tank port T is open.
[0072] FIG. 7 shows the hydraulic part 83 in the third position 3.
In this case, the activation of the coil has such a duty factor
that the piston 13 is displaced counter to the action of the
helical compression spring 9 into a middle position, which lies at
a stroke of 1.8 mm. In this case, the supply port P is closed in
the direction of the two working ports A, B by the middle outer web
51 and the outer web 53 disposed at the spring-side piston end 90.
Equally, the hydraulic flow from the second working port B to the
tank port T is closed because the hydraulic pressure is closed by
the outer web 50 positioned closest to the magnet part. The
hydraulic flow from and to the first working port A is blocked
because the outer web 53 at the spring-side piston end 90 is longer
in axial direction than the opening 88 of the first working port A,
with the result that the entire opening 88 is overlapped.
[0073] FIG. 8 shows the hydraulic part 83 in the fourth position 4.
In this case, the activation of the coil has such a duty factor
that the piston 13 is displaced counter to the action of the
helical compression spring 9 into a maximum end position, which
lies at a stroke of 3 mm. In this case, the supply port P is open
in the direction of the first working port A. On the other hand,
the hydraulic flow from the second working port B to the tank port
T is open, wherein the hydraulic fluid flows along the outer web 50
that is situated at the outermost magnet-side piston end 92.
[0074] FIG. 9 shows the piston 13 of the 4/4-way valve 83 of FIG. 2
to FIG. 8 as a single part in a perspective view.
[0075] FIG. 10 shows another piston 213 for a vane-type camshaft
adjuster system in a second example embodiment. This vane-type
camshaft adjuster system however, in contrast to the previous
example embodiment vane-type camshaft adjuster system, has no
mid-locking. Nevertheless the differences between the two pistons
13, 213 in relation to their overall manufacturing process are very
small. For instance, in contrast to the piston 13 with mid-locking
the piston 213 without mid-locking does not have an approximately
centrally disposed outer web 52. Furthermore, instead of the two
magnet-side outer webs 50, 51 only a single outer web 151 is
provided. This single outer web 151, in terms of the axial
delimitations 98, 99, has the axial delimitations 98, 99 of the
piston 13 with mid-locking. However, in contrast to the piston 13
with mid-locking, an annular groove 91 is not provided. Otherwise
the two pistons 13, 213 are of an identical type of design.
[0076] FIG. 11 shows a 4/3-way valve having the piston 213
according to FIG. 10. The piston 213 runs inside the bush 15 along
the running surface 85 thereof. The bush 15 according to this
embodiment is in this case of an identical design to the bush 15
according to the other embodiment according to FIG. 2 to FIG.
9.
[0077] From the diagram according to FIG. 13 it is however evident
that the 4/3-way valve of FIG. 11 and FIG. 12 is designed as a
4/3-way valve. In this case, the 4/3-way valve has the three
positions 2, 3, 4 and is proportionally controllable.
[0078] The flow from the supply port P to the first working port A
and/or the second working port B is accordingly controllable in
proportion to the current. In this case, just as in the 4/4-way
valve according to FIG. 4, there is a position 3, in which via the
run-off edges 200, 201 according to FIG. 11 a minimal hydraulic
pressure is applied to the two hydraulic chambers 109, 110 working
in opposite directions.
[0079] The constructionally identical design of the bushes in the
case of the use of different pistons to realize a vane-type
camshaft adjuster system in accordance with the present invention,
with and without a special outlet position for the mid-locking, may
be used also in vane-type camshaft adjuster systems with special
utilization of camshaft alternating torques, such as is described
for example in DE 10 2006 012 733 B4.
[0080] In this regard FIG. 14 to FIG. 16 show in a further example
embodiment the hydraulic part 283 for an electrohydraulic 4/4-way
valve of a vane-type camshaft adjuster system having a central axis
225. In this example embodiment, in contrast to FIG. 2 to FIG. 4,
no filters are provided in front of the openings 286, 288 of the
two working ports A, B. In the base of the annular grooves 260, 261
associated with these two working ports A, B, however, further
openings 262, 263 are provided for utilization of the camshaft
alternating torques. In contrast to the openings 286, 288 that are
exclusively blockable from inside by the outer webs 250, 251, 253,
the further openings 286, 288 have band-shaped non-return valves
270, 271. In each case a band-shaped non-return valve 270 and/or
271 is inserted into an inner annular groove 274 and/or 275
radially inside of the further opening 262 and/or 263 of the bush
215. By means of these non-return valves 270, 271 it is possible in
accordance with the method described in DE 10 2006 012 733 B4 for a
hydraulic pressure, which in the hydraulic chamber 109 and/or 110
to be relieved rises because of camshaft alternating torques for a
short time above the level of the hydraulic pressure in the
hydraulic chamber 110 and/or 109 to be loaded, to be made available
in the region of the supply port P. From this supply port P this
hydraulic pressure peak and/or this additional hydraulic fluid flow
is then made available, together with the hydraulic pressure
applied up by an oil pump 272 (visible in FIG. 16) to the supply
port P, to the hydraulic chamber 110 and/or 109 that is to be
loaded.
[0081] In this case, a third band-shaped non-return valve 276 is
additionally provided in an inner annular groove 277. This third
non-return valve 276 is however a pump protection valve, which is
basically of an identical construction to the two non-return valves
270, 271. This pump protection valve may however have a different
response force.
[0082] In an alternative example embodiment of the present
invention according to FIG. 14, filters are inserted also in the
annular grooves 260, 261.
[0083] FIG. 17, FIG. 18 and FIG. 19 show in a fourth example
embodiment the hydraulic part 383 for an electrohydraulic 4/3-way
valve of a vane-type camshaft adjuster system. This vane-type
camshaft adjuster system however, in contrast to the third example
embodiment of FIG. 14 to FIG. 16, has no mid-locking. In this case,
the same bush 215 is used as in the third example embodiment. The
piston 313 however differs from the piston 213 according to the
third example embodiment. Furthermore, the annular groove 291 for
the tank port T between the two outer webs 250, 251 that is shown
in FIG. 14 is not provided. Instead, the single outer web 351 is
not divided into two outer webs 250, 251 but is of an integral
construction. In terms of the axial delimitations 298, 299, this
single outer web 351 accordingly has the axial delimitations 298,
299 of the piston 13 with mid-locking. A further difference from
the third example embodiment is that an axially approximately
middle outer web 252 is not provided.
[0084] The previously described valve design embodiments are not
limited to proportional valves but may be used also in on-off
valves.
[0085] Depending on the operating conditions of the valve, filters
may be provided in front of all of the openings to protect the
running surfaces between piston and bush.
[0086] The hydraulic part of the illustrated valves may also be
used in a so-called master valve. In this case, the bush is not
connected directly to the magnet part. Instead, the hydraulic part
is disposed centrally in the rotor of the vane-type camshaft
adjuster so that the bush rotates jointly with the piston. The
magnet, on the other hand, is disposed in a rotationally fixed
manner relative to the cylinder head so that a relative movement
occurs between the tappet of the magnet part and the piston.
[0087] The described forms of construction are merely exemplary
embodiments. A combination of the described features for different
forms of construction is equally possible. For example, a set of
valves may be provided which includes different embodiments of
valves and pistons described herein. Such a set of valves may have
a modular construction. Further, in particular non-described
features of the device parts belonging to the invention are to be
gathered from the geometries of the device parts that are
represented in the drawings.
* * * * *