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US4247797A
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Rectangular AT-cut quartz resonator
Assignee: Seiko Instruments Inc
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Filing: 1979-04-25
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Granted: 1981-01-27
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Expires: 1999-04-25
Abstract
Abstract A rectangular AT-cut quartz resonator comprising a quartz crystal plate rotated about 35° around the X-axis, has dimensional ratios w/t and l/t respectively in the range of 3.1 to 3.7 and 14.5 to 16.2, where the length l, width w and thickness t are respectively along the X-axis, Z-axis, and Y-axis.
Inventors
- 👤 Naoyuki Echigo
- 👤 Shiro Yamashita
- 👤 Tsuneo Kuwabara
- 👤 Kunihiro Takahashi
- 👤 Shunichi Motte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:02
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02007; H03H9/02157; H03H9/02015; H03H9/02023
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
65 words
A rectangular AT-cut quartz resonator rotating a quartz crystal plate counterclockwise at about 35 degrees around the X-axis, wherein the length l, the width w and the thickness t of the quartz crystal plate are respectively along the X-axis, Z'-axis and Y'-axis, and dimensional ratios w/t and l/t are respectively chosen from the range of 3.1 to 3.7 and the range of 14.5 to 16.2.
Claim 2
Dependent Claim
65 words
A rectangular AT-cut quartz resonator rotating a quartz crystal plate counterclockwise at about 35 degrees around the X-axis, wherein the length l, the width w and the thickness t of the quartz crystal plate are respectively along the X-axis, Z'-axis and Y'-axis, and dimensional ratios w/t and l/t are respectively chosen from the range of 3.1 to 3.7 and the range of 14.5 to 16.2.
Claim 3
Dependent Claim
48 words
A rectangular AT-cut quartz resonator as claimed in claim 1, wherein the dimensional ratios w/t and l/t are chosen inside a quadrangle made of four points on coordinates composed of the abscissa w/t and the ordinate l/t (w/t, l/t): A(3.16, 15.94), B(3.40, 15.75), C(3.49, 15.12) and D(3.30, 15.17).
Claim 4
Dependent Claim
34 words
A rectangular AT-cut quartz resonator as claimed in claim 1, or claim 2, wherein both end portions in the length direction of the quartz resonator are finished into the shape of bevel or convex.
Claim 5
Dependent Claim
56 words
A rectangular AT-cut quartz resonator as claimed in claim 1 or claim 2, wherein both side surfaces of the quartz crystal resonator, that is the X-Y' planes, are tilted at about 5 degrees with respect to the normal to the principal faces of the crystal, the angle being measured in a counterclockwise direction around the X-axis.
References Cited (Backward Citations)
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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) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |