EP0405152A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for adjusting a spinning piezoelectric beam of a dual-axis angular rate sensor
Assignee: Japan Aviation Electronics Industry Ltd
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Filing: 1990-05-29
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Granted: —
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Expires: 2010-05-29
Abstract
Abstract A method for adjusting a spinning piezoelectric beam of a dual-axis angular rate sensor, in which the spinning piezoelectric beam is excited in a direction at right angles to the lengthwise direction of two piezoelectric sensors (22a, 22b) and to a rotary shaft (21); detected voltages of the two piezoelectric sensors (22a, 22b) are measured by a signal measuring circuit (30); a bending portion of at least one of the two piezoelectric sensors is ground so that the levels of the two measured signals and the difference therebetween become small; the spinning piezoelectric beam (20) is excited again in the lengthwise direction of the piezoelectric sensors (22a, 22b) at right angles to the rotary shaft (21); detected voltages of the two piezoelectric sensors are measured by the signal measuring circuit (30); and a weight mounted on the free end of at least one of the two piezoelectric sensors is ground so that the levels of the two measured signals and the difference therebetween become small. Thus, acceleration components applied to the spinning piezoelectric beam, in the detected voltages of the two piezoelectric sensors, are rendered to have the same phase and the same amplitude. On both sides of each piezoelectric sensor there are formed electrodes which are spaced 1.5 times the thickness of the sensor from support washers (24).
Inventors
- 👤 Kaneyuki C/O Japan Aviation Electronics Umemoto
- 👤 Toshio C/O Japan Aviation Electronics Tamura
- 👤 Teruo C/O Japan Aviation Electronics Yano
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 23:07
CPC Classifications
G; G01; G01C; G01C25/00; G01C25/005; G01C19/00; G01C19/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
227 words
A method for adjusting a spinning piezoelectric beam in which two beam-shaped piezoelectric sensors are affixed to a rotary shaft at right angles thereto and symmetrically with respect thereto while being gripped by support washers in parallel to each other and each of said piezoelectric sensors carries weights at its free end, said method comprising: a first step wherein said spinning piezoelectric beam is excited by an exciting unit in a direction perpendicular to said rotary shaft and to the lengthwise direction of said piezoelectric sensors, detected signals of said two piezoelectric sensors are measured by a signal measuring circuit, and a bending portion of at least one of said two piezoelectric sensors is ground until the detected voltages of said two piezoelectric sensors measured by said signal measuring circuit each become smaller than a predetermined first value and until their difference becomes smaller than a predetermined second value; and a second step wherein said spinning piezoelectric beam is excited by said exciting unit in the lengthwise direction of said piezoelectric sensors at right angles to said rotary shaft, and said weights of at least one of said two piezoelectric sensors are ground until the detected voltages of said two piezoelectric sensors measured by said signal measuring circuit each become smaller than a predetermined third value and until their difference becomes smaller than a predetermined fourth value.
Claim 2
Independent Claim
227 words
A method for adjusting a spinning piezoelectric beam in which two beam-shaped piezoelectric sensors are affixed to a rotary shaft at right angles thereto and symmetrically with respect thereto while being gripped by support washers in parallel to each other and each of said piezoelectric sensors carries weights at its free end, said method comprising: a first step wherein said spinning piezoelectric beam is excited by an exciting unit in a direction perpendicular to said rotary shaft and to the lengthwise direction of said piezoelectric sensors, detected signals of said two piezoelectric sensors are measured by a signal measuring circuit, and a bending portion of at least one of said two piezoelectric sensors is ground until the detected voltages of said two piezoelectric sensors measured by said signal measuring circuit each become smaller than a predetermined first value and until their difference becomes smaller than a predetermined second value; and a second step wherein said spinning piezoelectric beam is excited by said exciting unit in the lengthwise direction of said piezoelectric sensors at right angles to said rotary shaft, and said weights of at least one of said two piezoelectric sensors are ground until the detected voltages of said two piezoelectric sensors measured by said signal measuring circuit each become smaller than a predetermined third value and until their difference becomes smaller than a predetermined fourth value.
Claim 3
Dependent Claim
83 words
The adjusting method of claim 1 further including, prior to said first and second steps, a step wherein said spinning piezoelectric beam is excited by said exciting unit in the direction of said rotary shaft, and the amplitude and the phase of at least one of two signals measured by said signal measuring circuit supplied with the detected voltages of said two piezoelectric sensors are adjusted to thereby adjust said signal measuring circuit so that the difference between said two signals becomes minimum.
Claim 4
Dependent Claim
34 words
The adjusting method of claim 1 or 2, wherein the range of said bending portion to be ground is between said support washers and electrodes of the corresponding one of said two piezoelectric sensors.
Claim 5
Dependent Claim
39 words
The adjusting method of claim 3, wherein the range of said bending portion to be ground is a range of 1.5 times the thickness of said corresponding piezoelectric sensor from the marginal edge of each of said support washers.
Claim 6
Dependent Claim
65 words
A spinning piezoelectric beam which comprises two beam-shaped piezoelectric sensors affixed to a rotary shaft at right angles thereto and symmetrically with respect thereto while being gripped by support washers in parallel to each other, and wherein each of said piezoelectric sensors has electrodes on its both sides at a distance at least 1.2 times the thickness of said piezoelectric sensor from said support washers.
Claim 7
Dependent Claim
65 words
A spinning piezoelectric beam which comprises two beam-shaped piezoelectric sensors affixed to a rotary shaft at right angles thereto and symmetrically with respect thereto while being gripped by support washers in parallel to each other, and wherein each of said piezoelectric sensors has electrodes on its both sides at a distance at least 1.2 times the thickness of said piezoelectric sensor from said support washers.
Claim 8
Dependent Claim
21 words
The spinning piezoelectric sensor of claim 5, wherein said distance is more than 1.5 times the thickness of said piezoelectric sensor.
Claim 9
Dependent Claim
22 words
The spinning piezoelectric sensor of claim 5 or 6, wherein each of said piezoelectric sensors has weight means at its free end.
References Cited (Backward Citations)
No citation records indexed.
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