SOLENOID ASSEMBLY
TECHNICAL FIELD
The present invention relates to magnetic solenoids, including an assembly for
a magnetic solenoid configured for use in connection with a solenoid operated valve.
BACKGROUND
Magnetic solenoid valves are subject to tolerance "stack up" associated with the
inclusion of multiple components. To improve quality and functionality of solenoid
assemblies, including the function of an operating rod, there is commonly a desire to reduce
the stack up of associated dimensional tolerances. A reduction in tolerance stack-up can,
among other things, improve the alignment associated with operative components of the
assembly.
SUMMARY
A solenoid assembly for use in connection with a housing and valve body is
disclosed. The assembly includes a magnetic coil, a magnetic pole piece, an operating rod,
and a magnetic armature The operating rod is slidably disposed within a portion of the pole
piece and is at least in part centered relative to the pole piece. Activation of the coil provides
an attraction between the armature and the pole piece. An embodiment of the assembly may
additionally include one or more bearings positioned between the operating rod and the pole
piece.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described, by way of example, with
reference to the accompanying drawings, wherein:
FIG. 1 is a cross-sectional view of an assembly for a magnetic solenoid
according to an embodiment of the invention;
FIG. 2 is a cross-sectional view of an assembly for a magnetic solenoid
according to another embodiment of the invention; and
FIG. 3 is a cross-sectional view of an assembly for a magnetic solenoid
according to a further embodiment of the invention.
DETAILED DESCRIPTION
Reference will now be made in detail to embodiments of the present invention,
examples of which are described herein and illustrated in the accompanying drawings. While
the invention will be described in conjunction with embodiments, it will be understood that
they are not intended to limit the invention to these embodiments. On the contrary, the
invention is intended to cover alternatives, modifications and equivalents, which may be
included within the spirit and scope of the invention as defined by the appended claims.
An embodiment of a solenoid assembly 10 is shown in FIG. 1. In the illustrated
embodiment, the solenoid assembly 10 is shown as part of a larger valve assembly. The
illustrated solenoid assembly 10 includes a coil 12, a pole piece 14, an operating rod 16, and
an armature 18. A centerline for the assembly is generally designated as CL. A portion of a
valve body is generally designated as element 20. However, one of skill in the art will
recognize that the invention is not limited to a valve body 20 of the type shown, and other
forms and configurations of valve bodies may be employed without departing from the
teachings of the invention.
The coil 12, pole piece 14 and armature 18 are each configured to be at least
partially magnetic, and those components may be referred to as "magnetic."' In an
embodiment, the operating rod 16, which is sometimes referred to as a pin or operating pin, is
not comprised of a magnetic material and, hence, may be referred to as a "non-magnetic"
operating rod. For example, without limitation, the operating rod 16 may be comprised of
stainless steel, aluminum, or brass. The illustrated solenoid assembly 10 may also be referred
to as a magnetic solenoid or magnetic solenoid assembly.
At least a portion of pole piece 14 is positioned inside of coil 12. In the
illustrated embodiment, a majority of the pole piece that extend in the direction parallel to the
centerline CL of the assembly is positioned inside of coil 12.
In an embodiment of the invention, a pin or operating rod 16 is positioned
within a portion of a cavity or opening (such as a bore) formed by an inner surface of pole
piece 14. Rod 16 can be configured to generally extend longitudinally about the centerline
CL of the assembly 10. As shown, armature 18 is positioned about an end of operating rod
16 that is more remote from an end configured to communicate with a valve bod>' 20.
In an embodiment, operating rod 16 is slidably disposed within a portion of pole
piece 14, and extends beyond coil 12 and pole piece 14. The operating rod 16 can then, as
generally illustrated, further extend into a receiving portion of armature 18. The receiving
portion of armature 18 may comprise a cavity or aperture formed in a portion of the armature
positioned about centerline CL. Armature 18, which can be centered relative to pole piece
14, may also serve to keep the operating rod on a desired (e.g., "on-center" or centerline) path
with respect to other components of the assembly 10. In an embodiment of the invention, the
activation of coil 12 can provide an attraction between armature 18 and pole piece 14. For
example, such an activation can attract the £irmature 18 to pole piece 14. However, as
generally illustrated in FIG. 1, the assembly 10 may be configured such that, in at least one
operative state, coil 12 does not surround armature 18.
As generally illustrated, armature 18 can be configured to interact directly with
a portion of housing 22. That is, the assembly 10 can be configured such that at least a
portion of an associated flux travels from the pole piece 14, into and through the armature 18,
and directly on to a portion of an associated housing 22.
For some applications, such a configuration can eliminate the need for the
assembly to include a flux collector - which can reduce the number of necessary components
associated with the solenoid assembly. A reduction in the number of components can
potentially provide advantages, including a potential reduction in the "stack up" of
dimensional tolerances associated with various components of the solenoid assembly. For
example, because the invention does not require a conventional flux collector, the costs for
components may be reduced and the tolerance stack up of the assembly, for example in the
direction perpendicular to the centerline CL, can potentially also be reduced.
Moreover, for some applications, the improved "packaging" of the inventive
assembly (e.g., potential elimination of flux collector and/or reduction in tolerance stack-up)
can permit an armature to be designed to be larger, which can potentially provide for more
functional interaction between the armature and other components.
Another embodiment of the invention is generally illustrated in FIG. 2, where
similar components discussed in connection with the embodiment shown in FIG. 1 have been
designated with similar reference numerals. As discussed in connection with the prior
embodiment, the armature 18 may directly interact with a portion of housing 22; however, the
assembly 10 shown in FIG. 2 includes a bearing, and for most embodiments, a plurality of
bearings, e.g., 24a, 24b. In the illustrated embodiment, the bearings are positioned between a
portion of the pole piece 14 and a portion of the operating rod 16. For example, without
limitation, portions of the inner surface of pole piece 14 may be designed or configured to
retain or "seat" one or more bearings for operative communication with an operating rod 16.
Moreover, the bearings may be pressed into the pole piece 14 from opposing ends. Further,
as generally illustrated a spring element, e.g., spring 26, may be adapted for operative
connection with the operating rod 16. In the embodiment illustrated in FIG. 2, spring 26 is
positioned about the end of the operating rod about armature 18.
In an embodiment of the invention, assembly 10 includes at least two bearings.
In the illustrated embodiment, one bearing 24a is positioned about a first longitudinal half of
the operating rod 16, which in this case is the half adjacent the armature 18. A second
bearing 24b is positioned about a second longitudinal half of the operating rod 16. which in
the illustrated example is positioned closer to valve body 20. The sizing, position and
spacing of the associated plurality of bearings can be configured such that the operational rod
16 slides on the bearings 24a,24b, which keep the armature 18 substantially centered relative
to the pole piece 14.
Yet another embodiment of the invention is generally illustrated in FIG. 3. in
which similar components discussed in connection with the embodiments shown in FIGS. 1
and 2 have been designated with similar reference numerals. In this embodiment, the valve
body 20 is located on the other end of the solenoid assembly 10 when compared to the
assemblies shown in FIGS. I and 2. For such an alternative configuration, the valve body 20
is located on the same end as armature 18.
The embodiment depicted in FIG. 3 is shown without the inclusion of bearings;
however, one skilled in the art will understand that bearings, for example, as generally
disclosed in connection with the embodiment shown in FIG. 2, may be optionally included.
Further, as generally illustrated a spring element, e.g., spring 26, may be adapted for
operative connection with the operating rod 16. In the embodiment illustrated in FIG. 3,
spring 26 is positioned about the end of the operating rod remote from armature 18.
[00021] The foregoing descriptions of specific embodiments of the present invention
have been presented for purposes of illustration and description. They are not intended to be
exhaustive or to limit the invention to the precise forms disclosed, and various modifications
and variations are possible in light of the above teaching. The embodiments were chosen and
described in order to explain the principles of the invention and its practical application, to
thereby enable others skilled in the art to utilize the invention and various embodiments with
various modifications as are suited to the particular use contemplated. It is intended that the
scope of the invention be defined by the claims appended hereto and their equivalents.
WE CLAIM:
1. A solenoid assembly (10) for use in connection with a housing (22) and valve body
(20), the assembly (10) comprising:
a magnetic coil (12):
a magnetic pole piece (14), at least a portion of the pole piece (14) positioned inside
ofthecoil(12);
an operating rod (16) positioned within a portion of a cavity or aperture formed by the
pole piece (14); and
a magnetic armature (18) positioned about an end of the operating rod (16). the
armature (18) configured to interact directly with said housing (22);
wherein the operating rod (16) is slidably disposed within a portion of the pole piece
(14), the armature (18) is at least in part centered relative to the pole piece (14), and
activation of the coil (12) provides an attraction between the armature (18) and the pole piece
(14).
2. The assembly (10) of claim 1, wherein the magnetic armature (18) is positioned about
an end of the operating rod (16) that is more remote from said valve body (20).
3. The assembly (10) of claim 1, wherein the magnetic armature (18) is positioned about
an end of the operating rod (16) that is closer to said valve body (20).
4. The assembly (10) of claim 1, including a spring element (26) positioned about an end
of the operating rod (16) nearest the armature (18).
5. The assembly (10) of claim 1, including a spring element (26) positioned about an end
of the operating rod (16) that is more remote from the armature (18).
6. The assembly (10) of claim 1, wherein the operating rod (16) is comprised of non-
magnetic material.
7. The assembly (10) of claim 6, wherein the operating rod (16) is comprised of stainless
steel, aluminum, or brass.
8. The assembly (10) of claim 1, wherein the operating rod (16) is retained on-center by
the pole piece (14).
9. The assembly (10) of claim 1, wherein at least a portion of an associated flux travels
from the pole piece (14), into and through the armature (18), and directly on to said housing
(22).
10. The assembly (10) of claim 1, wherein the activation of the coil (12) attracts the
armature (18) to the pole piece (14).
11. The assembly (10) of claim 1, wherein an associated dimensional tolerance stack-up
for the assembly (10) consists solely of the tolerances associated with the coil (12), pole piece
(14), operating rod (16), and armature (18).
12. The assembly (10) of claim 1, wherein the majority of the external surface of the
operating rod (16) is in operative contact with an internal surface of the pole piece (14).
13. The assembly (10) of claim 1, wherein, when the coil (12) is in a non-activated
condition, the coil (12) does not surround the armature (18).
14. A solenoid assembly (10) for use in connection with a housing (22), the assembly (10)
comprising:
a magnetic coil (12);
a magnetic pole piece (14), at least a portion of the pole piece (14) positioned inside
the coil (12);
an operating rod (16) positioned within a portion of a cavity or aperture formed by the
magnetic pole piece (14);
a magnetic armature (18) positioned about one end of the operating rod (16). the
armature (18) configured to interact directly with said housing (22); and
at least one bearing (24a, 24b) positioned between a portion of the pole piece (14) and
a portion of the operating rod (16);
wherein the operating rod (16) is slidably disposed on the bearings (24a, 24b), the
armature (18) is at least in part centered relative to the pole piece (14), and activation of the
coil (12) provides an attraction between the armature (18) and the pole piece (14).
15. The assembly (10) of claim 14, including a spring element (26) positioned about an
end of the operating rod (16) nearest the armature (18).
16. The assembly (10) of claim 14, including a spring element (26) positioned about an
end of the operating rod (16) that is more remote from the armature (18).
17. The assembly (10) of claim 14, wherein a first bearing (24a) is positioned about a first
longitudinal half of the operating rod (16), and a second bearing (24b) is positioned about a
second longitudinal half of the operating rod (16).
18. The assembly (10) of claim 14, wherein the operating rod (16) is comprised of non-
magnetic material.
19. The assembly (10) of claim 14, wherein the operating rod (16) is comprised of
stainless steel, aluminum, or brass.
20. The assembly (10) of claim 14, wherein the operating rod (16) is retained on-center
by the at least one bearing (24a, 24b).
21. The assembly (10) of claim 17, wherein the operating rod (16) is retained on-center
by the first bearing (24a) and the second bearing (24b).
22. The assembly (10) of claim 14, wherein at least a portion of an associated flux travels
from the pole piece (14), into and through the armature (18), and directly on to said housing
(22).
23. The assembly (10) of claim 14, wherein the activation of the coil (12) attracts the
armature (18) to the pole piece (14).
24. The assembly (10) of claim 14, wherein an associated dimensional tolerance stack-up
for the assembly (10) consists of the tolerances associated with the coil (12), pole piece (14),
operating rod (16), bearings (24a, 24b), and armature (18).
25. The assembly (10) of claim 14, wherein the majority of the external surface of the
operating rod (16) is in operative contact with a surface associated with the at least one
bearing (24a, 24b) and an internal surface of the pole piece (14).
26. The assembly (10) of claim 14, wherein, when the coil (12) is in a non-activated
condition, the coil (12) does not surround the armature (18).
27. A solenoid assembly (10) for use in connection with a housing (22), the assembly (10)
comprising:
a magnetic coil (12);
a magnetic pole piece (14), at least a portion of the pole piece (14) positioned inside
the coil (12);
an operating rod (16) comprised of a non-magnetic material that is positioned within a
portion of a cavity or aperture formed by the magnetic pole piece (14);
a magnetic armature (18) positioned about one end of the operating rod (16). the
armature (18) configured to interact directly with said housing (22); and
at least one bearing (24a, 24b) positioned between a portion of the pole piece (14) and
a portion of the operating rod (16);
wherein the operating rod (16) is slidably disposed on the bearings (24a, 24b); the
armature (18) is at least in part centered relative to the pole piece (14); activation of the coil
(12) provides an attraction between the armature (18) and the pole piece (14); the operating
rod (16) is retained on-center by the at least one bearing (24a, 24b); and the activation of the
coil (12) attracts the armature (18) to the pole piece (14).
28. The assembly (10) of claim 27, wherein, when the coil (12) is in a non-activated
condition, the coil (12) does not surround the armature (18).

A solenoid assembly (10) for use in connection with a housing (22) and valve body
(20) is provided. The assembly (10) includes a magnetic coil (12), a magnetic pole piece
(14), an operating rod (16), and a magnetic armature (18). The operating rod (16) is slidably
disposed within a portion of the pole piece (14) and is at least in part centered relative to the
pole piece (14). Activation of the coil (12) provides an attraction between the armature (18)
and the pole piece (14). An embodiment of the assembly (10) may additionally include one
or more bearings (24a, 24b) positioned between the operating rod (16) and the pole piece
(14).