US3702073A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Accelerometer
Assignee: Sundstrand Data Control Inc
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Filing: 1969-02-28
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Granted: 1972-11-07
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Expires: 1989-02-28
Abstract
Abstract An accelerometer is provided for detecting acceleration which employs a flapper ring clamped at raised points between upper and lower portions of a magnet structure. The flapper is suspended by a bifilar hinge on the ring between two permanent magnets. Coils are mounted on opposite sides of the flapper, each encircling one of the permanent magnets and separated therefrom by an air gap. Each side of the flapper has a metallic coating thereby forming a capacitor with an inner face of the magnet structure on each side of the flapper. As the accelerometer is accelerated, the flapper is displaced relative to the magnet structure thus increasing the capacitance of one capacitor and decreasing the capacitance of the other capacitor. Electrical signals proportional to the change in the capacitances, and therefore proportional to the acceleration, are fed through a servo loop to the coil which set up a magnetic field which interacts with the magnetic fields of the permanent magnets to oppose the displacement of the flapper.
Inventors
- 👤 Earl D Jacobs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:37
CPC Classifications
G; G01; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/13; G01P15/132
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
178 words
An accelerometer for detecting the acceleration of an object to which it is attached, comprising: a stator structure having first and second stator members with opposed surfaces aligned along the sensitive axis of the accelerometer; an annular support member between the opposed surfaces of the stator structure and extending around said axis; at least three spacer means between the support member and each of the opposed surfaces of the stator structure, onE of said spacer means lying on the opposite side of the center of said support member from at least two other of said spacer means, the free angular spacing between said spacer means, about the center of said support member, being larger than the sum of the angular widths of said spacer means about said center; a flapper flexurally suspended from and inside the annular support member, between said opposed stator surfaces, for movement in response to acceleration along said axis; and a pair of capacitors, each capacitor having one plate on the flapper and another plate on the facing surface of the adjacent stator member.
Claim 2
Dependent Claim
178 words
An accelerometer for detecting the acceleration of an object to which it is attached, comprising: a stator structure having first and second stator members with opposed surfaces aligned along the sensitive axis of the accelerometer; an annular support member between the opposed surfaces of the stator structure and extending around said axis; at least three spacer means between the support member and each of the opposed surfaces of the stator structure, onE of said spacer means lying on the opposite side of the center of said support member from at least two other of said spacer means, the free angular spacing between said spacer means, about the center of said support member, being larger than the sum of the angular widths of said spacer means about said center; a flapper flexurally suspended from and inside the annular support member, between said opposed stator surfaces, for movement in response to acceleration along said axis; and a pair of capacitors, each capacitor having one plate on the flapper and another plate on the facing surface of the adjacent stator member.
Claim 3
Dependent Claim
41 words
The accelerometer of claim 1 in which said spacer means are posts extending axially of the accelerometer from said support member, each post having a contact face coated with malleable metal in engagement with the opposed surfaces of the stator members.
Claim 4
Dependent Claim
41 words
The accelerometer of claim 1 having a support member with two surfaces, and three spacer means on each surface of said support member, equally spaced around the support member, the spacer means on opposite surfaces of the support member being aligned.
Claim 5
Dependent Claim
31 words
The accelerometer of claim 1 in which said spacer means are posts having an angular width about the center of said support member of at least 5* and less than 15*.
Claim 6
Dependent Claim
17 words
The accelerometer of claim 1 in which said annular support member, flapper and spacer means are unitary.
Claim 7
Dependent Claim
19 words
The accelerometer of claim 5 in which said unitary support member, flapper and spacer means are of fused quartz.
Claim 8
Dependent Claim
36 words
The accelerometer of claim 1 in which said flapper is attached to said support member by a flexure and one of said spacer means lies on a diameter of said support member extending through said flexure.
Claim 9
Dependent Claim
27 words
The accelerometer of claim 7 having a support member with two surfaces and three spacer means on each surface of and equally spaced around said support member.
References Cited (Backward Citations)
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US3229530A
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US3339419A
Cited
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Cited
US3513711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-11-07 | 1976-05-08 | 1976-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-07 | 1980-05-08 | 1980-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-07 | 1984-05-08 | 1984-11-07 | $7700.00 | Window Closed / Lapsed |