Molded waveguide components having electroless plated thermoplastic members

• US 5,398,010 A
• Filed: 05/07/1992
• Issued: 03/14/1995
• Est. Priority Date: 05/07/1992
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Klebe, Douglas O.
• Primary Examiner(s): Lee, Benny T.
• Application Number:
  US07/880,123
• Time in Patent Office: 1,041 Days
• Field of Search: 333/239, 333/248, 333/241, 333/242, 156/304.2, 156/242, 156/245, 156/150, 156/292, 29/600, 138/139, 138/143, 138/145, 138/151, 138/157, 138/171
• US Class Current: 333/239
• CPC Class Codes: H01P 11/002 Manufacturing hollow waveguides
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

A microwave assembly having molded thermoplastic components that are first assembled into an enclosure, and then electroless copper plated to provide for RF conductivity. Assemblies are made by bonding bare thermoplastic components, after which the bonded assembly is electroless copper plated. The components are made of an injection molding material, polyetherimide, or a high strength, high temperature thermoplastic. The components are assembled using a one component epoxy adhesive, for example. All components are designed to be self locating to aid in assembly. A bonding fixture is used to apply clamping pressure to the components while the adhesive cures. After bonding, the waveguide assembly has its critical flange surfaces finish machined prior to plating.

Claims

1. A molded microwave waveguide component comprising:

a plurality of thermoplastic members having predefined shapes and sizes bonded with epoxy adhesive to define an enclosure, and wherein the enclosure has an internal electroless copper plated surface that is plated into a finished assembly in the fabrication thereof, and having a polyimide coating disposed over the copper plated surface, wherein the enclosure defining a microwave waveguide that is capable of transmitting microwave energy.

2. A molded microwave waveguide component fabricated by the process steps comprising:

fabricating a plurality of joinable thermoplastic members having predefined shapes and sizes;

joining the plurality of joinable thermoplastic members to form an enclosure having an internal surface by bonding the plurality of thermoplastic members together by means of epoxy adhesive;

electroless copper plating the internal surface of the enclosure to form a microwave waveguide that is capable of transmitting microwave energy;

coating the enclosure with polyimide that is disposed over the copper plated internal surface.

3. A molded microwave waveguide component comprising:

a plurality of thermoplastic members having predefined shapes and sizes that are coupled together to define an enclosure, and wherein the enclosure has an internal electroless copper plated surface that is plated into a finished assembly in fabrication thereof, the enclosure defining a microwave waveguide that is capable of transmitting microwave energy,

wherein the plurality of thermoplastic members comprise an interconnecting waveguide assembly that comprise a base and a mating cover, the base comprising a U-shaped member having a sidewall and a plurality of edgewalls contacting the sidewall to define a U-shaped cavity thereof, the cover comprising a U-shaped member that mates with the base, and having a sidewall and a plurality of edgewalls contacting the sidewall to define a U-shaped cavity thereof, and wherein the base and mating cover are coupled together to define the enclosure, and wherein inner surfaces thereof are electroless copper plated to define the enclosure, and the enclosure having a polyimide coating disposed over the internal electoless copper plated surface.

4. A molded microwave waveguide component comprising:

a plurality of thermoplastic members having predefined shapes and sizes that are coupled together to define an enclosure, and wherein the enclosure has an internal electroless copper plated surface that is plated into a finished assembly in fabrication thereof, the enclosure defining a microwave waveguide that is capable of transmitting microwave energy,

wherein the plurality of thermoplastic members comprise a center feed assembly that comprises a lower transition member having a plurality of slots disposed therein and a plurality of ridges disposed on an inner surface thereof, an upper transition member disposed adjacent to the lower transition section and having a plurality of ridges disposed on an inner surface thereof, a folded slot, transverse waveguide cover disposed over the upper transition member, and an input cover disposed over an input section of the folded slot, a transverse waveguide cover, and wherein the lower transition member, the upper transition member, the waveguide cover, and the input cover are coupled together to define the enclosure, and wherein the inner surfaces of the upper and lower transition members and inner surfaces of the waveguide and input covers are electroless copper plated to define the enclosure.

5. The molded microwave waveguide component of claim 4 which further comprises a polyimide coating disposed over the copper plated surface.