Patent Application
20080266038
The present invention relates to magnetic solenoids, including an assembly for a magnetic solenoid configured for use in connection with a solenoid operated valve.
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.
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.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, wherein:
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
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 body 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 armature 18 to pole piece 14. However, as generally illustrated in
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
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
The embodiment depicted in
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.
