US4521754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuning and temperature compensation arrangement for microwave resonators
Assignee: ITT Inc
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Filing: 1983-08-29
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Granted: 1985-06-04
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Expires: 2003-08-29
Abstract
Abstract The microwave resonator includes an enclosed resonator housing and a hollow central conductor having one end fastened to a bottom of the resonator housing and extending toward a top wall of the resonator housing. The other end of the central conductors is spaced from the top wall and includes an adjustable bellows assembly disposed coaxial of a longitudinal axis of the central conductor. A non-rotating, axially movable drive shaft is disposed coaxial of the axis of the central conductor within the central conductor. One end of the drive shaft is fastened to the bellows assembly and the other end of the drive shaft is coupled to a drive means disposed in the bottom wall to cause axial movement of the drive shaft to adjust the axial length of the bellows assembly and, hence, the axial length of the central conductor to adjust the resonant frequency of the microwave resonator. By selecting the material from which the housing and the central conductor is made to have a first selected coefficient of thermal expansion and by selecting the material the drive shaft is made from to have a second selected coefficient of thermal expansion. The first and second coefficients of thermal expansion are selected to minimize resonant frequency drift due to temperature variations and, hence, provides temperature compensation for the microwave resonator.
Inventors
- 👤 Joseph C. Ranghelli
- 👤 Joseph A. La Bella
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:39
CPC Classifications
H; H01; H01P; H01P7/00; H01P7/04
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
183 words
A microwave resonator having an adjustable resonant frequency comprising: an enclosed resonator housing; a hollow central conductor having one end fastened to a bottom wall of said housing and extending toward a top wall of said housing, the other end of said central conductor being spaced from said top wall and including an adjustable bellows assembly disposed coaxial of a longitudinal axis of said central conductor; and a non-rotating, axially movable drive shaft disposed coaxial of said axis within said central conductor, one end of said drive shaft being fastened to said bellows assembly and the other end of said drive shaft being coupled to a drive means disposed in said bottom wall to cause axial movement of said drive shaft to adjust the axial length of said bellows assembly and, hence, the axial length of said central conductor to adjust said resonant frequency; said drive means including a drive nut threaded onto said other end of said drive shaft and retained in a recess in the outer surface of said bottom wall, rotation of said drive nut axially moving said drive shaft.
Claim 2
Dependent Claim
183 words
A microwave resonator having an adjustable resonant frequency comprising: an enclosed resonator housing; a hollow central conductor having one end fastened to a bottom wall of said housing and extending toward a top wall of said housing, the other end of said central conductor being spaced from said top wall and including an adjustable bellows assembly disposed coaxial of a longitudinal axis of said central conductor; and a non-rotating, axially movable drive shaft disposed coaxial of said axis within said central conductor, one end of said drive shaft being fastened to said bellows assembly and the other end of said drive shaft being coupled to a drive means disposed in said bottom wall to cause axial movement of said drive shaft to adjust the axial length of said bellows assembly and, hence, the axial length of said central conductor to adjust said resonant frequency; said drive means including a drive nut threaded onto said other end of said drive shaft and retained in a recess in the outer surface of said bottom wall, rotation of said drive nut axially moving said drive shaft.
Claim 3
Dependent Claim
17 words
A resonator according to claim 1, wherein said housing is rectangular, and said central conductor is cylindrical.
Claim 4
Dependent Claim
70 words
A resonator according to claim 2, wherein said housing and said central conductor are made from a material having a first selected coefficient of thermal expansion, and said drive shaft is made from a material having a second selected coefficient of thermal expansion different than said first coefficient of thermal expansion, said first and second coefficients of thermal expansion being selected to minimize resonant frequency drift due to temperature variation.
Claim 5
Dependent Claim
24 words
A resonator according to claim 3, wherein said housing and central conductor are made from aluminum, and said drive shaft is made from invar.
Claim 6
Dependent Claim
64 words
A resonator according to claim 2, wherein said bellows assembly includes a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows.
Claim 7
Dependent Claim
44 words
A resonator according to claim 5, wherein said drive shaft has a flat portion disposed thereon engaging a flat portion in an aperture in said bottom end cap through which said drive shaft extends to prevent rotation of said drive shaft when moved axially.
Claim 8
Dependent Claim
45 words
A resonator according to claim 6, wherein said flat portion of said drive shaft provides a step which is in cooperation with said bottom end cap to define the total possible upward movement of said drive shaft and, hence, the maximum extension of said bellows.
Claim 9
Dependent Claim
53 words
A resonator according to claim 7, wherein said bottom end cap includes a portion surrounding said drive shaft within said bellows extending toward said top end cap to define in cooperation with said top end cap the total possible downward movement of said drive shaft and, hence, the maximum compression of said bellows.
Claim 10
Dependent Claim
42 words
A resonator according to claim 1, further including a locking cover disposed to engage said drive nut and to be fastened to the outer surface of said bottom wall to lock said drive nut in position after adjustment of said resonant frequency.
Claim 11
Dependent Claim
64 words
A resonator according to claim 9, wherein said bellows assembly includes a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows.
Claim 12
Dependent Claim
44 words
A resonator according to claim 10, wherein said drive shaft has a flat portion disposed thereon engaging a flat portion in an aperture in said bottom end cap through which said drive shaft extends to prevent rotation of said drive shaft when moved axially.
Claim 13
Dependent Claim
45 words
A resonator according to claim 11, wherein said flat portion of said drive shaft provides a step which is in cooperation with said bottom end cap to define the total possible upward movement of said drive shaft and, hence, the maximum extension of said bellows.
Claim 14
Dependent Claim
53 words
A resonator according to claim 12, wherein said bottom end cap includes a portion surrounding said drive shaft within said bellows extending toward said top end cap to define in cooperation with said top end cap the total possible downward movement of said drive shaft and, hence, the maximum compression of said bellows.
Claim 15
Dependent Claim
70 words
A resonator according to claim 1, wherein said housing and said central conductor are made from a material having a first selected coefficient of thermal expansion, and said drive shaft is made from a material having a second selected coefficient of thermal expansion different than said first coefficient of thermal expansion, said first and second coefficients of thermal expansion being selected to minimize resonant frequency drift due to temperature variation.
Claim 16
Dependent Claim
24 words
A resonator according to claim 14, wherein said housing and central conductor are made from aluminum, and said drive shaft is made from invar.
Claim 17
Dependent Claim
46 words
A resonator according to claim 14, wherein said drive means includes a drive nut threaded onto said other end of said drive shaft and retained in a recess in the outer surface of said bottom wall, rotation of said drive nut axially moving said drive shaft.
Claim 18
Dependent Claim
42 words
A resonator according to claim 16, further including a locking cover disposed to engage said drive nut and to be fastened to the outer surface of said bottom wall to lock said drive nut in position after adjustment of said resonant frequency.
Claim 19
Dependent Claim
64 words
A resonator according to claim 17, wherein said bellows assembly includes a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows.
Claim 20
Dependent Claim
44 words
A resonator according to claim 18, wherein said drive shaft has a flat portion disposed thereon engaging a flat portion in an aperture in said bottom end cap through which said drive shaft extends to prevent rotation of said drive shaft when moved axially.
Claim 21
Dependent Claim
45 words
A resonator according to claim 19, wherein said flat portion of said drive shaft provides a step which is in cooperation with said bottom end cap to define the total possible upward movement of said drive shaft and, hence, the maximum extension of said bellows.
Claim 22
Dependent Claim
53 words
A resonator according to claim 20, wherein said bottom end cap includes a portion surrounding said drive shaft within said bellows extending toward said top end cap to define in cooperation with said top end cap the total possible downward movement of said drive shaft and, hence, the maximum compression of said bellows.
Claim 23
Dependent Claim
64 words
A resonator according to claim 1, wherein said bellows assembly includes a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows.
Claim 24
Dependent Claim
44 words
A resonator according to claim 22, wherein said drive shaft has a flat portion disposed thereon engaging a flat portion in an aperture in said bottom end cap through which said drive shaft extends to prevent rotation of said drive shaft when moved axially.
Claim 25
Dependent Claim
45 words
A resonator according to claim 23, wherein said flat portion of said drive shaft provides a step which is in cooperation with said bottom end cap to define the total possible upward movement of said drive shaft and, hence, the maximum extension of said bellows.
Claim 26
Dependent Claim
53 words
A resonator according to claim 24, wherein said bottom end cap includes a portion surrounding said drive shaft within said bellows extending toward said top end cap to define in cooperation with said top end cap the total possible downward movement of said drive shaft and, hence, the maximum compression of said bellows.
Claim 27
Dependent Claim
215 words
A microwave resonator having an adjustable resonant frequency comprising: an enclosed resonator housing; a hollow central conductor having one end fastened to a bottom wall of said housing and extending toward a top wall of said housing, the other end of said central conductor being spaced from said top wall and including an adjustable bellows assembly disposed coaxial of a longitudinal axis of said central conductor; and a non-rotating, axially movable drive shaft disposed coaxial of said axis within said central conductor, one end of said drive shaft being fastened to said bellows assembly and the other end of said drive shaft being coupled to a drive means disposed in said bottom wall to cause axial movement of said drive shaft to adjust the axial length of said bellows assembly and, hence, the axial length of said central conductor to adjust said resonant frequency; said bellows assembly including a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows, said drive shaft being engaged by said bottom end cap to prevent rotation thereof.
Claim 28
Dependent Claim
215 words
A microwave resonator having an adjustable resonant frequency comprising: an enclosed resonator housing; a hollow central conductor having one end fastened to a bottom wall of said housing and extending toward a top wall of said housing, the other end of said central conductor being spaced from said top wall and including an adjustable bellows assembly disposed coaxial of a longitudinal axis of said central conductor; and a non-rotating, axially movable drive shaft disposed coaxial of said axis within said central conductor, one end of said drive shaft being fastened to said bellows assembly and the other end of said drive shaft being coupled to a drive means disposed in said bottom wall to cause axial movement of said drive shaft to adjust the axial length of said bellows assembly and, hence, the axial length of said central conductor to adjust said resonant frequency; said bellows assembly including a top end cap fastened to said one end of said drive shaft, a bottom end cap fastened to said central conductor adjacent said other end thereof, and a bellows disposed between and fastened to said top and bottom end caps, said drive shaft extending through said bottom end cap and said bellows, said drive shaft being engaged by said bottom end cap to prevent rotation thereof.
Claim 29
Dependent Claim
46 words
A resonator according to claim 26, wherein said drive means includes a drive nut threaded onto said other end of said drive shaft and retained in a recess in the outer surface of said bottom wall, rotation of said drive nut axially moving said drive shaft.
Claim 30
Dependent Claim
42 words
A resonator according to claim 27, further including a locking cover disposed to engage said drive nut and to be fastened to the outer surface of said bottom wall to lock said drive nut in position after adjustment of said resonant frequency.
Claim 31
Dependent Claim
44 words
A resonator according to claim 26, wherein said drive shaft has a flat portion disposed thereon engaging a flat portion in a aperture in said bottom end cap through which said drive shaft extends to prevent rotation of said drive shaft when moved axially.
Claim 32
Dependent Claim
45 words
A resonator according to claim 29, wherein said flat portion of said drive shaft provides a step which is in cooperation with said bottom end cap to define the total possible upward movement of said drive shaft and, hence, the maximum extension of said bellows.
Claim 33
Dependent Claim
53 words
A resonator according to claim 30, wherein said bottom end cap includes a portion surrounding said drive shaft within said bellows extending toward said top end cap to define in cooperation with said top end cap the total possible downward movement of said drive shaft and, hence, the maximum compression of said bellows.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |