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US4255729A Expired / Lapsed US ⏱️ 0.0 years remaining

High frequency filter

Assignee: Oki Electric Industry Co Ltd
•
Filing: 1979-05-09
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Granted: 1981-03-10
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Expires: 1999-05-09
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Abstract

Abstract A high frequency filter for frequencies higher than the VHF band comprising at least one resonator has been found. Each resonator comprises a conductive housing, an inner conductor one end of which is fixed at the bottom of the housing and the other end of which is free standing, a cylindrical dielectric body surrounding said inner conductor, and the diameter of the dielectric body is approximately four times as large as that of said inner conductor.

Inventors

  • 👤 Atsushi Fukasawa
  • 👤 Jun Ashiwa
  • 👤 Takuro Sato

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 19:38
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/201; H01P1/205; H01P1/2056

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 148 words
A high frequency filter comprising a conductive housing, at least two resonators fixed in said housing, an input means for coupling one end resonator of said at least two resonators to an external circuit, an output means for coupling the other end resonator of said at least two resonators to an external circuit, and coupling means for electromagnetically coupling each resonator, characterized in that each resonator comprises an inner conductor one end of which is fixed at the bottom of said housing, and the other end of which is free standing, wherein the length of said inner conductor is substantially 1/4 wavelength, a cylindrical dielectric body surrounding said inner conductor, the thickness of said dielectric body being sufficient to hold substantially all the electromagnetic energy in the dielectric body, wherein electromagnetic energy is applied to said filter through said input means, and exits therefrom through said output means.
Claim 2
Dependent Claim 148 words
A high frequency filter comprising a conductive housing, at least two resonators fixed in said housing, an input means for coupling one end resonator of said at least two resonators to an external circuit, an output means for coupling the other end resonator of said at least two resonators to an external circuit, and coupling means for electromagnetically coupling each resonator, characterized in that each resonator comprises an inner conductor one end of which is fixed at the bottom of said housing, and the other end of which is free standing, wherein the length of said inner conductor is substantially 1/4 wavelength, a cylindrical dielectric body surrounding said inner conductor, the thickness of said dielectric body being sufficient to hold substantially all the electromagnetic energy in the dielectric body, wherein electromagnetic energy is applied to said filter through said input means, and exits therefrom through said output means.
Claim 3
Dependent Claim 148 words
A high frequency filter comprising a conductive housing, at least two resonators fixed in said housing, an input means for coupling one end resonator of said at least two resonators to an external circuit, an output means for coupling the other end resonator of said at least two resonators to an external circuit, and coupling means for electromagnetically coupling each resonator, characterized in that each resonator comprises an inner conductor one end of which is fixed at the bottom of said housing, and the other end of which is free standing, wherein the length of said inner conductor is substantially 1/2 wavelength, a cylindrical dielectric body surrounding said inner conductor, the thickness of said dielectric body being sufficient to hold substantially all the electromagnetic energy in the dielectric body, wherein electromagnetic energy is applied to said filter through said input means, and exits therefrom through said output means.
Claim 4
Dependent Claim 148 words
A high frequency filter comprising a conductive housing, at least two resonators fixed in said housing, an input means for coupling one end resonator of said at least two resonators to an external circuit, an output means for coupling the other end resonator of said at least two resonators to an external circuit, and coupling means for electromagnetically coupling each resonator, characterized in that each resonator comprises an inner conductor one end of which is fixed at the bottom of said housing, and the other end of which is free standing, wherein the length of said inner conductor is substantially 1/2 wavelength, a cylindrical dielectric body surrounding said inner conductor, the thickness of said dielectric body being sufficient to hold substantially all the electromagnetic energy in the dielectric body, wherein electromagnetic energy is applied to said filter through said input means, and exits therefrom through said output means.
Claim 5
Dependent Claim 20 words
A high frequency filter according to either lf claims 1 or 2, wherein said coupling means is a loop antenna.
Claim 6
Dependent Claim 19 words
A high frequency filter according to either of claims 1 or 2, wherein said coupling means is a capacitor.
Claim 7
Dependent Claim 50 words
A high frequency filter according to either of claims 1 or 2, wherein said coupling means is an electrode attached on the surface of said dielectric body so that said electrode confronts the electrode of the next resonator, and a conductor connected electrically to the housing extends between the electrodes.
Claim 8
Dependent Claim 24 words
A high frequency filter according to either of claims 1 or 2, wherein a conductive wall is provided between resonators to prevent stray coupling.
Claim 9
Dependent Claim 39 words
A high frequency filter according to either of claims 1 or 2, wherein said coupling means is a conductive wire provided near open end of the inner conductor, and said conductive wire is positioned perpendicular to said inner conductor.
Claim 10
Dependent Claim 26 words
A high frequency filter according to either claims 1 or 2, wherein said coupling means is a loop antenna provided near the bottom of the housing.
Claim 11
Dependent Claim 38 words
A high frequency filter according to either of claims 1 or 2, wherein said dielectric body of the resonator has an electrode on the surface of the dielectric body, and said electrode is electrically connected to the housing.
Claim 12
Dependent Claim 31 words
A high frequency filter according to either of claims 1 or 2, wherein the diameter of the dielectric body is approximately four times as large as that of the inner conductor.
Claim 13
Dependent Claim 26 words
A high frequency filter according to either of claims 1 or 2, wherein said resonator has a frequency adjust screw rotatably inserted in the inner conductor.

References Cited (Backward Citations)

US2516056A Cited
US4028652A Cited
US4059815A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-03-09 1984-09-08 1985-03-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-03-09 1988-09-08 1989-03-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-03-09 1992-09-08 1993-03-10 $7700.00 Window Closed / Lapsed

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