Patent US3787786A successfully refreshed from Google Patents.
US3787786A
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US
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Continuously variable ultrasonic delay line
Assignee: Government of France
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Filing: 1972-11-09
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Granted: 1974-01-22
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Expires: 1992-11-09
Abstract
Abstract Delay line comprising an extended piezoelectric element and two input and output electrode systems cooperating with the surface of this element, characterized in that at least one of the two systems comprises at least one movable part which follows the longitudinal direction of the piezoelectric element, this movable part forming an upper electrode situated close to the active face of the piezoelectric element. Application to the realization of ultrasonic delay lines with continuous variation.
Inventors
- 👤 A Defebvre
- 👤 G Leman
- 👤 J Pouliquen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:31
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/30; H03H9/42; H03H9/423
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
92 words
Delay line comprising an extended piezoelectric element and two input and output electrode systems cooperating with the surface of this element, at least one of the two systems comprising at least one movable part which follows the longitudinal direction of the piezoelectric element, this movable part forming an upper electrode situated close to the active face of the piezoelectric element, wherein one of the two systems of electrodes is a fixed comb deposited on said active face, the other system comprising said upper electrode and a grid comb deposited on said face.
Claim 2
Dependent Claim
92 words
Delay line comprising an extended piezoelectric element and two input and output electrode systems cooperating with the surface of this element, at least one of the two systems comprising at least one movable part which follows the longitudinal direction of the piezoelectric element, this movable part forming an upper electrode situated close to the active face of the piezoelectric element, wherein one of the two systems of electrodes is a fixed comb deposited on said active face, the other system comprising said upper electrode and a grid comb deposited on said face.
Claim 3
Dependent Claim
15 words
Delay line in accordance with claim 1, wherein the upper electrode is flat and rectangular.
Claim 4
Dependent Claim
43 words
Delay line in accordance with claim 3, wherein the transverse dimension of said upper electrode is less than the length of the teeth of the associated grid comb, and the longitudinal dimension is less than or equal to that of the other comb.
Claim 5
Dependent Claim
43 words
Delay line in accordance with claim 1, wherein the movable part is inclined in relation to the face opposite the piezoelectric element, so that its distance from said face decreases during its longitudinal translation in the direction of propagation of the acoustic waves.
Claim 6
Dependent Claim
108 words
Delay line in accordance with claim 1, comprising a case containing the piezoelectric element placed at the bottom, the two systems of electrodes and electronic input and output circuits, the upper electrode being carried by an insulating block controlled, with regard to translation, by a micrometer screw, and sliding in a guide formed by two side walls of the case, wherein the movable electrode is formed on the lower face of a part which can slide, perpendicularly to the face opposite the piezoelectric element, in a recess made in said insulating block, which is itself integral with a female screw whose rotation is blocked on the micrometer screw.
Claim 7
Dependent Claim
23 words
Delay line in accordance with claim 5, wherein said piece is cylindrical, and capable of being adjusted by rotation in the said recess.
Claim 8
Dependent Claim
18 words
Delay line in accordance with claim 1, wherein said fixed comb is covered by an earthed conducting screen.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |