US4503352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grooved piezoelectric ceramic resonator with two poling directions
Assignee: Murata Manufacturing Co Ltd
•
Filing: 1983-12-15
•
Granted: 1985-03-05
•
Expires: 2003-12-15
Abstract
Abstract An improved piezoelectric ceramic resonator in which spurious vibration other than that in a longitudinal direction of a piezoelectric ceramic plate is suppressed. The directions of polarization of the rectangular piezoelectric ceramic plate at opposite sides of a concave groove provided in the piezoelectric ceramic plate are different from each other, and are unequal in magnitude. A portion of the plate between the oppositely polarized portions is not polarized in any predetermined direction. The resulting arrangement improves a spurious characteristic of the piezoelectric ceramic resonator, and also rectifies an imbalance in selectivity characteristic between a high frequency side and a low frequency side, when the resonator is used in an electrical filter.
Inventors
- 👤 Jiro Inoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:57
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/54; H03H9/56; H03H9/562; H03H9/542
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
227 words
A piezoelectric ceramic resonator for vibrating in a length vibration mode, comprising: a rectangular piezoelectric ceramic plate having first and second axially opposite ends and an approximately constant width between said first and second ends; said plate having first and second opposite main surfaces and a thickness therebetween; said plate further having a groove defined in said first main surface, said first main surface having first and second parts on opposite sides of said groove, said groove extending axially between said first and second ends for separating said first and second parts; said plate including a first portion between said first part of said first main surface and said second main surface, a second portion between said second part of said first main surface and said second main surface and a third portion between said first and second portions and between said groove and said second main surface; said first portion being polarized in a first direction along said thickness of said plate to a first degree; said second portion being polarized in a second direction opposite said first direction to a second degree less than said first degree; said third portion not being polarized in any predetermined direction; first and second split electrodes formed on said first and second parts of said first main surface; and an entire face electrode formed on said second main surface.
Claim 2
Dependent Claim
227 words
A piezoelectric ceramic resonator for vibrating in a length vibration mode, comprising: a rectangular piezoelectric ceramic plate having first and second axially opposite ends and an approximately constant width between said first and second ends; said plate having first and second opposite main surfaces and a thickness therebetween; said plate further having a groove defined in said first main surface, said first main surface having first and second parts on opposite sides of said groove, said groove extending axially between said first and second ends for separating said first and second parts; said plate including a first portion between said first part of said first main surface and said second main surface, a second portion between said second part of said first main surface and said second main surface and a third portion between said first and second portions and between said groove and said second main surface; said first portion being polarized in a first direction along said thickness of said plate to a first degree; said second portion being polarized in a second direction opposite said first direction to a second degree less than said first degree; said third portion not being polarized in any predetermined direction; first and second split electrodes formed on said first and second parts of said first main surface; and an entire face electrode formed on said second main surface.
Claim 3
Dependent Claim
45 words
A piezoelectric ceramic resonator as claimed in claim 1, wherein said first and second split electrodes are respectively connected to an input terminal and an output terminal, said entire face electrode being connected to a ground terminal for application as a three terminal type resonator.
Claim 4
Dependent Claim
42 words
A piezoelectric ceramic resonator as claimed in claim 1, wherein said first and second split electrodes are respectively connected to an input terminal and an output terminal, said entire face electrode having no connection, for application as a two terminal type resonator.
Claim 5
Dependent Claim
207 words
A piezoelectric ceramic resonator, comprising: a rectangular piezoelectric ceramic plate having first and second axially opposite ends and an approximately constant width between said first and second ends; said plate having first and second opposite main surfaces and a thickness therebetween; said plate further having a groove defined in said first main surface, said first main surface having first and second parts on opposite sides of said groove, said groove extending axially between said first and second ends for separating said first and second parts; said plate including a first portion between said first part of said first main surface and said second main surface, a second portion between said second part of said first main surface and said second main surface and a third portion between said first and second portions and between said groove and said second main surface; said first portion being polarized in a first direction along said thickness of said plate; said second portion being polarized in a second direction opposite said first direction; said third portion not being polarized in any predetermined direction; first and second split electrodes formed on said first and second parts of said first main surface; and an entire face electrode formed on said second main surface.
Claim 6
Dependent Claim
207 words
A piezoelectric ceramic resonator, comprising: a rectangular piezoelectric ceramic plate having first and second axially opposite ends and an approximately constant width between said first and second ends; said plate having first and second opposite main surfaces and a thickness therebetween; said plate further having a groove defined in said first main surface, said first main surface having first and second parts on opposite sides of said groove, said groove extending axially between said first and second ends for separating said first and second parts; said plate including a first portion between said first part of said first main surface and said second main surface, a second portion between said second part of said first main surface and said second main surface and a third portion between said first and second portions and between said groove and said second main surface; said first portion being polarized in a first direction along said thickness of said plate; said second portion being polarized in a second direction opposite said first direction; said third portion not being polarized in any predetermined direction; first and second split electrodes formed on said first and second parts of said first main surface; and an entire face electrode formed on said second main surface.
Claim 7
Dependent Claim
45 words
A piezoelectric ceramic resonator as claimed in claim 4, wherein said first and second split electrodes are respectively connected to an input terminal and an output terminal, said entire face electrode being connected to a ground terminal for application as a three terminal type resonator.
Claim 8
Dependent Claim
42 words
A piezoelectric ceramic resonator as claimed in claim 4, wherein said first and second split electrodes are respectively connected to an input terminal and an output terminal, said entire face electrode having no connection, for application as a two terminal type resonator.
References Cited (Backward Citations)
US2875355A
Cited
US3374367A
Cited
US3562792A
Cited
DE2163377A1
Cited
US4019073A
Cited
US4368402A
Cited
US4431938A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-04 | 1988-09-03 | 1989-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-04 | 1992-09-03 | 1993-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-04 | 1996-09-03 | 1997-03-05 | $7700.00 | Window Closed / Lapsed |