Patent Application
20060214751
Microwave components such as waveguide diplexer assemblies are typically formed by machining complementary pairs of cavity networks in two halves. The two halves mate together along a first planar surface to form the desired waveguide, filter and mixing passages. Input and output waveguide ports are provided in planar port surfaces typically normal to and each bisected by the first planar surface.
To environmentally seal the waveguide assembly, a sealing gasket is required along the first planar surface and also around each of the input and output ports. Because the first planar surface bisects each of the input and or output ports a small gap exists between a sealing gasket applied to the first planar surface and each intersection with separate input and or output port sealing gasket(s).
Previously, unitary sealing gaskets for multiple planar surfaces have applied foldable portions containing a secondary gasket surface that may be folded to align with a different planar sealing surface, the circumference of the seal formed not intersecting the primary surface. Also, a sealing gasket such as an o-ring may be turned upon itself to form two or more sealing loops each of which may be aligned with a desired planar sealing surface. However, this solution also fails where one sealing surface must intersect another. Further, a small gap is created at each sealing loop intersection as the gasket crosses itself. Alternatively, liquid or semi-liquid sealing material calks such as silicone or the like may be manually applied to a sealing groove that then forms a single use gasket upon hardening. Each of the prior solutions either fails to completely seal the assembly, is inapplicable to the intersecting sealing planes of a waveguide assembly and or requires an undesirably high level of installation skill, time and or cost.
The increasing competition for microwave assemblies has focused attention on cost reductions resulting from increased materials, manufacturing and service efficiencies. Further, reductions in required assembly operations and the total number of discrete parts are desired.
Therefore, it is an object of the invention to provide an apparatus that overcomes deficiencies in the prior art.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general and detailed descriptions of the invention appearing herein, serve to explain the principles of the invention.
According to the invention, a single unitary sealing gasket is adapted for sealing along a first plane and one or more different planar surfaces that are, for example, bisected by the first plane. Because the resulting sealing gasket is unitary, there are no gaps formed between the sealing surfaces of the first plane and the one or more different planar surfaces.
The sealing gasket may be cost effectively manufactured, for example, by injection molding of liquid and or semi-liquid materials such as rubber, acrylic, silicon, epdm, nitrile or the like into multiple dies adapted to mate together to form a three dimensional mold. Multiple die three dimensional injection molding technology is well known and is therefore not further described herein in greater detail. The cost increase resulting from production and application of the more than two dies necessary to form the three dimensional structure of the sealing gasket is overcome by the improved sealing performance and or installation inefficiencies related to alternative sealing gasket solutions.
As shown in
In the present embodiment, the second and third planes are aligned normal to the first plane. In alternative configurations, the ports and associated secondary loop(s) 45 may be at any desired angle of alignment with each other according to the requirements of waveguide feature(s) 15 and or the desired port interconnection orientations.
As shown, the sealing groove(s) 10 are formed along the primary sealing surface loop 7 in the first portion 20. Alternatively, the sealing groove(s) 10 along the first plane may be formed in both the first and second portion(s) 20, 25.
The intersection of the sealing gasket 5 along the primary surface sealing loop of the first plane with the secondary loop (s) of the sealing gasket 5 secondary loop(s) 45 around the input and output port(s) 35, 40 in the second and third planes may be formed as a straight-on connection to the secondary loop(s) 45 as shown with respect to the input port(s) 35. Alternatively, the intersection may be adapted to enter the plane of the input and or output port 35, 40, within the area surrounded by the secondary loop 45, and then connect to the secondary loop 45 from a direction parallel to the plane, as shown for example with respect to the output port 40. This arrangement is useful for configurations where minimized port dimensions are desired, for example where the port attachment is via a surrounding outer clamp.
In use, the sealing gasket 5 may be first aligned along the first plane in the sealing groove(s) of the first portion 20 of the waveguide assembly 30, as shown in
One skilled in the art will appreciate that the invention similarly applies to a sealing gasket configuration for any waveguide assembly 30 having any number of different input and or output port(s) 35, 40 intersecting with a first plane that divides first and second portions of the waveguide assembly 30. For example, as shown in
Although the secondary loop(s) 45 have been demonstrated in the present exemplary embodiments as each bisected by the primary sealing surface loop, depending upon the arrangement of the waveguide feature(s) 15 between the first portion 20 and the second portion 25 and or the desired port configuration, the intersection may appear at any two points along the secondary loop 45. Also, the primary sealing surface loop 7 of the first plane may have any circumferential configuration depending upon the dimensions and layout of the applicable waveguide assembly 30 (not shown).
Where in the foregoing description reference has been made to ratios, integers, components or modules having known equivalents then such equivalents are herein incorporated as if individually set forth.
While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus, methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant's general inventive concept. Further, it is to be appreciated that improvements and/or modifications may be made thereto without departing from the scope or spirit of the present invention as defined by the following claims.
