Helix resonator filter

• US 5,418,508 A
• Filed: 11/23/1993
• Issued: 05/23/1995
• Est. Priority Date: 11/23/1992
• Status: Expired due to Fees

• Current Assignee: Filtronic LK Oy
• Original Assignee: Pulse Finland Oy (Yageo Corporation)
• Inventors: Puurunen, Pertti
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US08/157,361
• Time in Patent Office: 546 Days
• Field of Search: 333/202, 333/219, 333/206, 333/243, 333/244, 333/222, 333/245
• US Class Current: 333/202
• CPC Class Codes: H01P 1/2053 the coaxial cavity resonators being disposed parall to each other

Abstract

A filter construction known in the art comprises at least a number of helix resonators (1) and an insulation material plate, the projections (2a) projecting from the rectangular lower part (2) whereof are provided inside the helix resonators and thus supporting them. The filter housing (6), defined by a cover (8) and the side walls, is provided with compartments, so that each compartment includes a helical resonator. As taught by the invention, at least two guides (71) projecting from the surface are extruded in the same phase as the compartment on the inner surface of the cover, wherebetween the tip part of the projection (2a) supporting the resonator enters when the filter is assembled. The guide can be a hemisphere or a rib-like bulge.

Claims

1. A helix resonator filter assembly, comprising:

at least one helically wound electrical conductor supported by an insulating member, said insulating member having an insulating portion extending beyond an end of said at least one helically wound electrical conductor;

an extrusion formed housing defining an interior space and having guide means extending into said interior space, said at least one helically wound electrical conductor and supporting insulating member being disposed within said interior space;

said guide means including a pair of guide members that are extrusions and are free of bent portions, said guide members each extending within said interior space and being configured and spaced apart for guiding said insulating portion therebetween.

2. A helix resonator filter assembly as set forth in claim 1, wherein said guide means comprise elongated ribs.

3. A helix resonator filter assembly as set forth in claim 2, wherein said ribs extend from one side wall (9) of the housing to an opposite side wall of said housing.

4. A helix resonator filter assembly as set forth in claim 2, wherein the length of said ribs are smaller than the distance between side walls of said housing and that the ends of the ribs are rounded.

5. A helix resonator filter assembly as set forth in claim 1, wherein said guide means comprises hemispheres.

6. A helix resonator filter assembly as set forth in any preceding claim, wherein further guide means are formed on inner surfaces of end faces of said housing and extend into said interior space, ends of a lower part of said insulating member being disposed between the further guide means, said further guide means being free of bent portions.

7. A helix resonator filter assembly as set forth in claim 6, wherein said further guide means comprise two parallel ribs extending from a lower edge of said housing towards a cover of said housing.

8. A helix resonator filter assembly as set forth in claim 6, wherein said further guide means comprise at least two semi-spherical bulges.

9. A helix resonator filter assembly as set forth in claim 1 or 6, wherein said insulating portion have metallized end portions and said insulating member is fixed into said housing by soldering said metallized end portions to said guide means.

10. A helix resonator filter assembly as set forth in claim 6, wherein the ends of the lower part of said insulating member have metallized end portions and said insulating member is fixed into said housing by soldering said metallized end portions to said further guide means.

11. A method of assembling a helix resonator filter, comprising the steps of:

supporting at least one helically wound electrical conductor by an insulating member, said insulating member having an insulating portion extending beyond an end of said at least one helically wound electrical conductor;

extrusion forming a housing that defines an interior space and that has a pair of guide members extending into said interior space,

disposing said at least one helically wound electrical conductor and supporting insulating member within said interior space, said pair of guide members being extrusions that are free of bent portions, said pair of guide members extending within said interior space and each being configured and spaced apart from each other for guiding said insulating portion therebetween.

12. A method as in claim 11, further comprising the step of guiding said insulating member between said guide members.

13. A method as in claim 11, further comprising the step of forming said guide members and said housing substantially contemporaneously by extrusion.

14. A method as in claim 11, further comprising the step of forming further guide members on inner surfaces of end faces of said housing and thereafter disposing ends of a lower part of said insulating member between said further guide members.

15. A method as in claim 14, wherein ends of the lower part of said insulating member are metallized;

further comprising the step of fixing said insulating member into said housing by soldering said metallized end portions to said further guide members.

16. A method as in claim 11, wherein ends of the said insulating member are metallized;

further comprising the step of fixing said insulating member into said housing by soldering said metallized end portions to said guide members.