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Patent Abstract
A proportional solenoid valve for a high-pressure diesel pump of
a motor vehicle has a housing and a solenoid with an armature movable
in the housing. A bushing is provided, and a piston is arranged
in the bushing. The armature acts on the piston for moving the piston
in the bushing as a function of a current supply to the solenoid.
At least one component is positioned between the bushing and the
housing and is deformable in an axial direction of the piston so
as to allow an exact adjustment of the position of the piston relative
to the bushing.
Patent Claims
What is claimed is:
1. A proportional solenoid valve for a high-pressure diesel pump
of a motor vehicle, the proportional solenoid valve comprising:
a housing (2); a solenoid (1) comprising an armature (5) movable
in the housing (2); a bushing (20); a piston (6) arranged in the
bushing (20); wherein the armature (5) acts on the piston (6) for
moving the piston (6) in the bushing (20) as a function of a current
supply to the solenoid (1); at least one component (34) positioned
between the bushing (20) and the housing (2) and deformable in an
axial direction of the piston (6).
2. The solenoid valve according to claim 1, wherein the at least
one component (34) is elastically deformable.
3. The solenoid valve according to claim 1, wherein the at least
one component (34) is plastically deformable.
4. The solenoid valve according to claim 1, wherein the at least
one component (34) is a gasket.
5. The solenoid valve according to claim 1, wherein the at least
one component (34) rests against an end face of the bushing (20)
and an end face of the housing (2).
6. The solenoid valve according to claim 1, wherein the piston
(6) is adapted to be pressed into the armature (5) to different
positions within the armature (5) allowing positional adjustment
of the piston (6) in an exact mounting position.
7. The solenoid valve according to claim 1, wherein the armature
(5) is supported by the piston (6) in the bushing (20).
8. The solenoid valve according to claim 1, wherein the housing
(2) has a cup member (4) and wherein the armature (5) projects with
radial play into the cup member (4).
9. The solenoid valve according to claim 1, wherein the armature
(5) is moved against a counter force when the solenoid (1) is supplied
with current.
10. The solenoid valve according to claim 9, further comprising
a spring (18) providing the counter force.
11. The solenoid valve according to claim 1, wherein the piston
(6) is made from a bearing needle.
12. The solenoid valve according to claim 1, wherein the bushing
(20) is adapted to be inserted into a receptacle (13) of a hydraulic
component (14), wherein the bushing (20) has at least one sealing
ring (27, 32) for play compensation when the bushing (20) is seated
in the receptacle (13).
13. The solenoid valve according to claim 1, wherein the solenoid
(1) has a pole core (15) arranged movably in the housing (2) for
adjusting a magnetic force of the solenoid (1).
14. The solenoid valve according to claim 1, wherein the housing
(2) is adapted to be screwed into a receptacle (13) of the hydraulic
component (14).
15. The solenoid valve according to claim 1, further comprising
a securing part (36) functioning as a transport securing device
placed onto a free end of the piston (6).
16. The solenoid valve according to claim 15, wherein the securing
part (36) is cup-shaped.
17. The solenoid valve according to claim 15, wherein the securing
part (36) is made of plastic material.
18. A proportional solenoid valve for a high-pressure diesel pump
of a motor vehicle, the proportional solenoid valve comprising:
a housing (2); a solenoid (1) comprising an armature (5) movable
in the housing (2); a bushing (20); a piston (6) arranged in the
bushing (20); wherein the armature (5) acts on the piston (6) for
moving the piston (6) in the bushing (20) as a function of a current
supply to the solenoid (1); wherein the piston (6) is adapted to
be pressed into the armature (5) to different positions within the
armature (5) allowing positional adjustment of the piston (6) in
an exact mounting position.
19. The solenoid valve according to claim 18, wherein the armature
(5) is supported by the piston (6) in the bushing (20).
20. The solenoid valve according to claim 18, wherein the housing
(2) has a cup member (4) and wherein the armature (5) projects with
radial play into the cup member (4).
21. The solenoid valve according to claim 18, wherein the armature
(5) is moved against a counter force when the solenoid (1) is supplied
with current.
22. The solenoid valve according to claim 21, further comprising
a spring (18) providing the counter force.
23. The solenoid valve according to claim 18, wherein the piston
(6) is made from a bearing needle.
24. The solenoid valve according to claim 18, wherein the bushing
(20) is adapted to be inserted into a receptacle (13) of a hydraulic
component (14), wherein the bushing (20) has at least one sealing
ring (27, 32) for play compensation when the bushing (20) is seated
in the receptacle (13).
25. The solenoid valve according to claim 18, wherein the solenoid
(1) has a pole core (15) arranged movably in the housing (2) for
adjusting a magnetic force of the solenoid (1).
26. The solenoid valve according to claim 18, wherein the housing
(2) is adapted to be screwed into a receptacle (13) of a hydraulic
component (14).
27. The solenoid valve according to claim 18, further comprising
a securing part (36) functioning as a transport securing device
placed onto a free end of the piston (6).
28. The solenoid valve according to claim 27, wherein the securing
part (36) is cup-shaped.
29. The solenoid valve according to claim 27, wherein the securing
part (36) is made of plastic material.
Patent Description
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a proportional solenoid valve,
preferably a proportional throttle valve, especially for high-pressure
diesel pumps of motor vehicles, comprising a solenoid with an armature
that is movable within a housing and provided to move a piston in
a bushing as a function of the supplied current.
[0003] 2. Description of the Related Art
[0004] The piston of the proportional solenoid valve must be precisely
adjusted so that a satisfactory throttling function is achieved.
This adjustment is complex and difficult.
SUMMARY OF INVENTION
[0005] It is an object of the present invention to configure the
proportional solenoid valve of the aforementioned kind such that
the piston can be precisely positioned in a simple way relative
to the bushing.
[0006] In accordance with the present invention, this is achieved
in that between the bushing and the housing at least one component
is positioned that is deformable in the axial direction of the piston.
[0007] In the proportional solenoid valve according to the invention
the bushing is moved against the deformable component so that the
bushing can be adjusted in a precise mounting position. During this
adjusting process, the component is axially deformed in the axial
direction of the bushing and of the piston arranged therein. In
this way, the bushing can be moved in a very simple but precise
way into the required mounting position.
[0008] In one embodiment according to the invention, the piston
can be very precisely positioned in the exact mounting position
by being pressed to the required extent into the armature. This
provides for a highly precise positioning of the piston.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 is an axial section of the throttle valve according
to the invention.
[0010] FIG. 2 is a section view of a positional securing device
of the piston of the throttle valve according to the invention.
DETAILED DESCRIPTION
[0011] The throttle valve is used advantageously in high-pressure
diesel pumps of motor vehicles and is embodied as a proportional
throttle valve. It comprises a proportional solenoid 1 with a housing
2 in which a coil 3 is arranged. The coil 3 surrounds a cup member
4 which is of a hood-shaped embodiment. An armature 5 projects into
the cup member 4. The armature 5 is seated with press-fit on one
end of a piston 6. The armature 5 is cup-shaped and projects with
radial play into the cup member 4. A cup-shaped shielding member
7 is provided in the cup member 4 and has a bottom 8 resting on
the bottom 9 of the cup member 4. The bottom 8 of the shielding
member 7 is centrally provided with a raised portion 10 which is
formed by a plastic deformation of the bottom 8. The armature 5
rests against the raised portion 10. The free end of the shielding
member 7 overlaps a cylindrical projection 11 of a housing part
12 with which the proportional solenoid 1 is pressed into a receptacle
13 of a hydraulic component 14.
[0012] The piston 6 extends through a pole core 15 which is inserted
into the housing part 12. The inner wall 16 of the pole core 15
is widened at its end facing the armature 5 so that a radial shoulder
surface 17 is formed. The radial shoulder 17 supports one end of
a pressure coil spring 18 whose other end is supported on the end
face of the armature 5. By means of the pressure coil spring 18,
the armature 5, and thus also the piston 6, is forced against the
raised portion 10 of the bottom 8 of the shielding member 7 when
the proportional solenoid 1 is not switched on.
[0013] The inner wall 19 of the receptacle 13 is reduced with respect
to its diameter at a location spaced from the housing part 12. In
this area, a bushing 20 rests against the inner wall 19 with its
outer peripheral surface. In the bushing 20 the piston 6 is guided.
The bushing 20 has at its outer peripheral surface two annular grooves
21, 22 positioned at an axial spacing from one another. Radial bores
23, 24 which are uniformly distributed about the circumference of
the bushing 20 open into the grooves 21, 22 and penetrate the bushing
20. The hydraulic component 14 has two bores 25, 26 allowing flow
of hydraulic medium. The bores 25, 26 can be opened and closed by
means of the piston 6 in a way to be described in the following.
[0014] At the end facing away from the proportional solenoid 1,
the inner wall 19 of the receptacle 13 passes by means of a radially
inwardly oriented shoulder surface 27 into a central bore 28 having
a diameter which is reduced relative to the receptacle 13. The free
end of the piston 6 projects with radial play into this bore 28.
The hydraulic bushing 20 rests against the shoulder 27 with interposition
of an annular seal 29. The hydraulic bushing 20 is provided at its
free end with an annular groove 30 that is open in a direction toward
the end face, and the annular seal 29 is positioned in this groove
30.
[0015] The hydraulic bushing 20 is provided with annular groove
31 arranged in the area between the annular grooves 21, 22. This
groove 31 receives an additional annular seal 32 resting sealingly
against the inner wall 19 of the receptacle 13.
[0016] The receptacle 13 widens conically at the end facing the
proportional valve 1. In this way, a receiving space for an annular
seal 33 is formed with which the end face of the housing 2 of the
proportional valve 1 is sealed relative to the hydraulic component
14.
[0017] The hydraulic bushing 20 has an axial spacing from the end
face of the housing part 12. Between the end face of the hydraulic
bushing 20 and the end face of the housing part 12 at least one
component 34 is provided that is elastically or plastically deformable
in the axial direction. The component 34 is preferably a gasket.
By means of this deformable component 34, the hydraulic bushing
20 can be adjusted in a simple way into the required mounting position.
By moving the bushing 20 against the component 34, a precise adjustment
of the mounting position of the bushing 20 is ensured. Alternatively,
or in addition, to this measure the piston 6 can be pressed into
the armature 5 to different positions within the armature 5 allowing
positional adjustment of the piston 6 in its exact mounting position.
The adjustment of the solenoid force is realized by movement of
the pole core 15 in the housing 2. The armature 5 is simply radially
centered by means of the piston 6 in the bushing 20.
[0018] The piston 6 is provided with an annular groove 35.
[0019] The bushing 20 is inserted into the receptacle 13 of the
hydraulic component 14 so that the bores 25, 26 can open into the
annular grooves 21, 22. The piston 6 is pressed to such an extent
into the armature 5 that the annular groove 21 and the radial bores
23 opening into it are closed by the piston 6 when the armature
5 rests under the force of the pressure spring 18 against the raised
portion 10 of the bottom 8 of the shielding member 7 (FIG. 1). The
annular groove 35 in the piston 6 has such a length that in this
position the bore 26 of the hydraulic component 14 communicates
via the radial bores 24 with the annular groove 35.
[0020] When the proportional solenoid 1 is excited, depending on
the strength of the current that is supplied, the armature 5 is
moved against the force of the pressure spring 18. When doing so,
it entrains the piston 6. Already after a short movement path or
stroke, the radial bores 23 are released by the piston 6 so that
the hydraulic medium can flow from the bore 25 via the annular groove
35 into the bore 26. Depending on the movement path of the piston
6, the opening cross-section of the radial bores 23 can be adjusted
continuously. The throttle effect can be adjusted in an optimal
way. With a corresponding supply of current of the proportional
solenoid 1, the armature 5 and thus the piston 6 can be moved to
such an extent that the radial bores 24 are completely closed by
means of the piston 6.
[0021] The piston 6 can be inexpensively manufactured, for example,
from a bearing needle. The sealing rings 27, 32 on the bushing 20
ensure in a simple way a radial play compensation in the receptacle
13 of the hydraulic component 14. The proportional throttle valve
is comprised only of a few components which can be positioned in
the required mounting position as a function of the described configuration
and arrangement.
[0022] Onto the end of the piston 6 projecting into the bore 28,
a securing part 36 (FIG. 2) can be placed which serves as a transport
securing device for preventing loss of the bushing 20 during transport.
The securing part 36 is cup-shaped and is comprised advantageously
of plastic material. It is seated on the piston end and provides
a clamping action; it can be simply removed before mounting the
solenoid 1 in the hydraulic component 14.
[0023] The deformable component 34 can be made of plastic material,
rubber, or any other suitable deformable material. The proportional
solenoid 1 can be simply screwed with the housing part 12 into the
receptacle 13 so that a simple connection of the proportional solenoid
1 to the hydraulic bushing 20 is ensured.
[0024] While specific embodiments of the invention have been shown
and described in detail to illustrate the inventive principles,
it will be understood that the invention may be embodied otherwise
without departing from such principles.
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