US4638669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quantum tunneling cantilever accelerometer
Assignee: Massachusetts Institute of Technology
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Filing: 1985-05-07
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Granted: 1987-01-27
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Expires: 2005-05-07
Abstract
Abstract A highly sensitive accelerometer is disclosed in which the current is measured across a pair of electrodes resulting from voltage pulses from a pulse generator. The electrodes are located within a vacuum chamber. One of the electrodes is cantilevered and has its free end suspended over the other fixed electrode. The amount of current through the vacuum gap between the electrodes is determinative of acceleration since the current is an exponential function of the distance between the electrodes and the distance between the electrodes changes linearly with acceleration.
Inventors
- 👤 Stephen Y. Chou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:21
CPC Classifications
G; G01; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/0894
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
103 words
An accelerometer comprising; a vacuum chamber; an electrode fixed in position within said vacuum chamber; a cantilevered electrode located within said vacuum chamber having a fixed end and a free end, the free end of said cantilevered electrode being aligned with and separated from said fixed electrode such that acceleration of said accelerometer causes the free end of said cantilevered electrode to move towards said fixed electrode; means for providing a voltage pulse across said fixed electrode and said cantilevered electrode; and means for measuring the current flow caused by said voltage pulse, the amount of acceleration being determinable from the current measurement.
Claim 2
Dependent Claim
103 words
An accelerometer comprising; a vacuum chamber; an electrode fixed in position within said vacuum chamber; a cantilevered electrode located within said vacuum chamber having a fixed end and a free end, the free end of said cantilevered electrode being aligned with and separated from said fixed electrode such that acceleration of said accelerometer causes the free end of said cantilevered electrode to move towards said fixed electrode; means for providing a voltage pulse across said fixed electrode and said cantilevered electrode; and means for measuring the current flow caused by said voltage pulse, the amount of acceleration being determinable from the current measurement.
Claim 3
Dependent Claim
20 words
The accelerometer of claim 1 wherein the current flow caused by said voltage pulse is substantially composed of tunneling current.
Claim 4
Dependent Claim
14 words
The accelerometer of claim 1 wherein said current measuring means comprises a pulse ammeter.
Claim 5
Dependent Claim
26 words
The accelerometer of claim 1 further comprising an insulation layer covering said fixed electrode so that said cantilevered electrode is prevented from touching said fixed electrode.
Claim 6
Dependent Claim
78 words
A highly sensitive accelerometer comprising; a vacuum chamber; an electrical insulation member located within said vacuum chamber; an electrode fixed on said insulation member; a cantilevered electrode having one end fixed on said insulation member and a free end suspended over said fixed electrode; a pulse generator which provides a voltage pulse across said fixed electrode and said cantilevered electrode; and means for measuring the current across the vacuum gap between said fixed electrode and said cantilevered electrode.
Claim 7
Dependent Claim
78 words
A highly sensitive accelerometer comprising; a vacuum chamber; an electrical insulation member located within said vacuum chamber; an electrode fixed on said insulation member; a cantilevered electrode having one end fixed on said insulation member and a free end suspended over said fixed electrode; a pulse generator which provides a voltage pulse across said fixed electrode and said cantilevered electrode; and means for measuring the current across the vacuum gap between said fixed electrode and said cantilevered electrode.
Claim 8
Dependent Claim
20 words
The accelerometer of claim 5 wherein the current flow caused by said voltage pulse is substantially composed of tunneling current.
Claim 9
Dependent Claim
14 words
The accelerometer of claim 5 wherein said current measuring means comprises a pulse ammeter.
Claim 10
Dependent Claim
26 words
The accelerometer of claim 5 further comprising an insulation layer covering said fixed electrode so that said cantilevered electrode is prevented from touching said fixed electrode.
Claim 11
Independent Claim
74 words
A method for making highly sensitlive acceleration measurements comprising; providing a vacuum chamber; generating a voltage pulse across a pair of electrodes located within the vacuum chamber, one electrode in cantilever suspension over the other electrode such that the distance between said electrodes provides a measure of acceleration; and measuring the current flow caused by said voltage pulse, said current measurement providing a measure of the distance between the electrodes and hence the acceleration.
Claim 12
Independent Claim
74 words
A method for making highly sensitlive acceleration measurements comprising; providing a vacuum chamber; generating a voltage pulse across a pair of electrodes located within the vacuum chamber, one electrode in cantilever suspension over the other electrode such that the distance between said electrodes provides a measure of acceleration; and measuring the current flow caused by said voltage pulse, said current measurement providing a measure of the distance between the electrodes and hence the acceleration.
Claim 13
Dependent Claim
20 words
The method of claim 9 wherein the current flow caused by said voltage pulse is substantially composed of tunneling current.
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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) | 1990-01-26 | 1990-07-28 | 1991-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-26 | 1994-07-28 | 1995-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-26 | 1998-07-28 | 1999-01-27 | $7700.00 | Window Closed / Lapsed |