Patent US3739304A successfully refreshed from Google Patents.
US3739304A
Expired / Lapsed
US
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Resonator interconnections in monolithic crystal filters
Assignee: AT&T Inc
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Filing: 1971-09-27
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Granted: 1973-06-12
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Expires: 1991-09-27
Abstract
Abstract In a multiresonator modified monolithic crystal filter employing a combination of mass loading and acoustic coupling, a direct nongrounded conductor, external to the piezoelectric body between two of the resonators, establishes a second transmission path through the filter. Attenuation peaks with control over their position are established thereby which enhances filter selectivity.
Inventors
- 👤 A Braun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:25
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/54; H03H9/56; H03H9/566
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
123 words
A monolithic crystal filter comprising, in combination, a plurality of resonators each including a respective portion of a common piezoelectric body sandwiched between a respective pair of electrodes, said resonators including an input resonator, an output resonator and at least two auxiliary resonators, a nongrounded, floating, short circuiting, conducting path external to said body connecting one electrode of one of said auxiliary resonators to a corresponding electrode of another of said auxiliary resonators, both of said auxiliary resonators being nonshorted an input point and means independent of said path directly connecting said input point to an electrode of said input resonator, and an output point and means independent of said path directly connecting said output point to an electrode of said output resonator.
Claim 2
Dependent Claim
123 words
A monolithic crystal filter comprising, in combination, a plurality of resonators each including a respective portion of a common piezoelectric body sandwiched between a respective pair of electrodes, said resonators including an input resonator, an output resonator and at least two auxiliary resonators, a nongrounded, floating, short circuiting, conducting path external to said body connecting one electrode of one of said auxiliary resonators to a corresponding electrode of another of said auxiliary resonators, both of said auxiliary resonators being nonshorted an input point and means independent of said path directly connecting said input point to an electrode of said input resonator, and an output point and means independent of said path directly connecting said output point to an electrode of said output resonator.
Claim 3
Dependent Claim
27 words
Apparatus in accordance with claim 1 wherein the number of said auxiliary resonators exceeds two, and means shorting each of said auxiliary resonators that is otherwise unconnected.
Claim 4
Dependent Claim
22 words
Apparatus in accordance with claim 2 including means connecting one side of each of said resonators to a source of reference potential.
Claim 5
Dependent Claim
19 words
Apparatus in accordance with claim 1 wherein said auxiliary resonators are positioned substantIally between said input and output resonators.
Claim 6
Dependent Claim
26 words
Apparatus in accordance with claim 1 wherein said resonators are in substantial alignment and said input resonator is positioned substantially between two of said auxiliary resonators.
Claim 7
Dependent Claim
20 words
Apparatus in accordance with claim 1 wherein said input and output resonators are positioned between two of said auxiliary resonators.
Claim 8
Dependent Claim
122 words
A monolithic crystal filter comprising, in combination, a plurality of resonators each including a respective portion of a common piezoelectric body sandwiched between a respective pair of electrodes, said resonators including an input resonator, an output resonator and at least two auxiliary resonators, a nongrounded, short circuiting conducting path external to said body connecting one electrode of one of said auxiliary resonators to a corresponding electrode of another of said auxiliary resonators, both of said auxiliary resonators being nonshorted an input point and means independent of said path directly connecting said input point to an electrode of said input resonator, and an output point and means independent of said path directly connecting said output point to an electrode of said output resonator.
Claim 9
Dependent Claim
122 words
A monolithic crystal filter comprising, in combination, a plurality of resonators each including a respective portion of a common piezoelectric body sandwiched between a respective pair of electrodes, said resonators including an input resonator, an output resonator and at least two auxiliary resonators, a nongrounded, short circuiting conducting path external to said body connecting one electrode of one of said auxiliary resonators to a corresponding electrode of another of said auxiliary resonators, both of said auxiliary resonators being nonshorted an input point and means independent of said path directly connecting said input point to an electrode of said input resonator, and an output point and means independent of said path directly connecting said output point to an electrode of said output resonator.
Claim 10
Dependent Claim
19 words
Apparatus in accordance with claim 7 wherein said auxiliary resonators are positioned substantially between said input and output resonators.
Claim 11
Dependent Claim
26 words
Apparatus in accordance with claim 7 wherein said resonators are in substantial alignment and said input resonator is positioned substantially between two of said auxiliary resonators.
Claim 12
Dependent Claim
20 words
Apparatus in accordance with claim 7 wherein said input and output resonators are positioned between two of said auxiliary resonators.
Claim 13
Dependent Claim
19 words
Apparatus in accordance with claim 7 including a capacitor connected between said path and a source of reference potential.
Claim 14
Dependent Claim
19 words
Apparatus in accordance with claim 11 wherein said auxiliary resonators are positioned substantially between said input and output resonators.
Claim 15
Dependent Claim
26 words
Apparatus in accordance with claim 18 wherein said resonators are in substantial alignment and said input resonator is positioned substantially between two of said auxiliary resonators.
Claim 16
Dependent Claim
20 words
Apparatus in accordance with claim 11 wherein said input and output resonators are positioned between two of said auxiliary resonators.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |