Patent US5581034A successfully refreshed from Google Patents.
US5581034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Convective accelerometer and inclinometer
Assignee: Rosemount Aerospace Inc
•
Filing: 1995-01-13
•
Granted: 1996-12-03
•
Expires: 2015-01-13
Abstract
Abstract A convective accelerometer and inclinometer includes two temperature sensing elements mounted within a sealed enclosure containing a gas. The application of heat to the gas within the enclosure by a heating element causes the gas to flow in a predetermined pattern in free convection. When linear acceleration or inclination is applied to the enclosure the convective flow of gas is affected causing a temperature differential between the temperature sensing elements. This temperature differential is measured as a difference in electrical resistance between the two temperature sensing elements which is proportional to the acceleration. The device can be used to measure linear acceleration, velocity, position or inclination. The device can also be used as an inclinometer for measuring the angle of gravity. The device has a wide variety applications particularly within the automotive field.
Inventors
- 👤 Ricardo Dao
- 👤 Denny E. Morgan
- 👤 Harold H. Kries
- 👤 David M. Bachelder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:27
CPC Classifications
G; G01; G01P; G01P15/00; G01P15/18; G01C; G01C9/00; G01C9/02; G01P15/006; G01P15/008; G01P15/02; G01P15/08; G01P15/12
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
91 words
A device for sensing acceleration, position, velocity or inclination comprising: an enclosure containing a fluid; heating means for heating the fluid in the enclosure; two substantially parallel temperature sensing elements positioned within said enclosure such that the fluid moves across the two temperature sensing elements in free convection; and circuit means connected to the two temperature sensing elements for determining acceleration, position, velocity or inclination based on the effect of acceleration on the free convective flow within the enclosure; wherein the heating means is provided by the two temperature sensing elements.
Claim 2
Independent Claim
91 words
A device for sensing acceleration, position, velocity or inclination comprising: an enclosure containing a fluid; heating means for heating the fluid in the enclosure; two substantially parallel temperature sensing elements positioned within said enclosure such that the fluid moves across the two temperature sensing elements in free convection; and circuit means connected to the two temperature sensing elements for determining acceleration, position, velocity or inclination based on the effect of acceleration on the free convective flow within the enclosure; wherein the heating means is provided by the two temperature sensing elements.
Claim 3
Dependent Claim
28 words
The device of claim 1, wherein the heating means provides uniform heating to the two temperature sensing elements when no acceleration or inclination is applied to the enclosure.
Claim 4
Dependent Claim
15 words
The device of claim 2, wherein at least one temperature sensing element is a wire.
Claim 5
Dependent Claim
36 words
The device of claim 1, wherein when the enclosure is subjected to a linear acceleration or inclination, a temperature differential is created between the temperature sensing elements due to a change in convection within the enclosure.
Claim 6
Dependent Claim
23 words
The device of claim 1, wherein the heating means further comprises an additional heating element for minimizing the effect of environmental temperature changes.
Claim 7
Dependent Claim
34 words
The device of claim 5, wherein when the enclosure is subjected to acceleration or inclination, a temperature differential is created between the temperature sensing elements due to a change in convection within the enclosure.
Claim 8
Dependent Claim
30 words
The device of claim 5, further comprising mounting means for mounting the temperature sensing elements, wherein the circuit means is connected to the temperature sensing elements by the mounting means.
Claim 9
Dependent Claim
40 words
The device of claim 1, further comprising mounting means for mounting the heating means within the enclosure, and wherein the heating means is configured so that free convection in the enclosure prevails over conduction of heat through the mounting means.
Claim 10
Dependent Claim
37 words
The device of claim 1, wherein the temperature sensing elements are positioned within the enclosure at a sufficient distance from the enclosure so that free convection in the enclosure prevails over radiation of heat through the enclosure.
Claim 11
Dependent Claim
17 words
The device of claim 1, wherein the fluid is a gas having desirable convective heat transfer characteristics.
Claim 12
Dependent Claim
20 words
The device of claim 10, wherein the gas includes at least one of nitrogen, helium, argon, xenon, neon and krypton.
Claim 13
Dependent Claim
13 words
The device of claim 1, further comprising two arc shaped temperature sensing elements.
Claim 14
Dependent Claim
17 words
The device of claim 1, wherein the at least one temperature sensing element is a coiled filament.
Claim 15
Dependent Claim
15 words
The device of claim 1, further comprising signal conditioning electronics for performing output voltage amplification.
Claim 16
Dependent Claim
20 words
The device of claim 1, further comprising a constant current source for providing electric power to the temperature sensing elements.
Claim 17
Dependent Claim
37 words
The device of claim 1, further comprising a second device for sensing acceleration, position, velocity or inclination having at least one temperature sensing element and positioned perpendicular to the device for sensing acceleration, position, velocity or inclination.
Claim 18
Dependent Claim
14 words
The device of claim 1, further comprising signal conditioning electronics for performing temperature compensation.
Claim 19
Dependent Claim
15 words
The device of claim 1, further comprising signal conditioning electronics for performing frequency response modification.
Claim 20
Independent Claim
116 words
A device for sensing acceleration or inclination comprising: a hermetically sealed enclosure containing a fluid; heating means for heating the fluid in the enclosure; at least two parallel temperature sensing elements having first and second ends, said temperature sensing elements mounted within said enclosure such that the fluid moves across the sensing elements in free convection; and circuit means connected to the first and second ends of the temperature sensing elements for determining at least one of acceleration and inclination based on the difference in temperature between the temperature sensing elements resulting from the effect of acceleration on free convective flow within the enclosure, wherein the heating means are the at least two temperature sensing elements.
Claim 21
Independent Claim
116 words
A device for sensing acceleration or inclination comprising: a hermetically sealed enclosure containing a fluid; heating means for heating the fluid in the enclosure; at least two parallel temperature sensing elements having first and second ends, said temperature sensing elements mounted within said enclosure such that the fluid moves across the sensing elements in free convection; and circuit means connected to the first and second ends of the temperature sensing elements for determining at least one of acceleration and inclination based on the difference in temperature between the temperature sensing elements resulting from the effect of acceleration on free convective flow within the enclosure, wherein the heating means are the at least two temperature sensing elements.
Claim 22
Independent Claim
94 words
A device for sensing acceleration, position, velocity or inclination comprising: heating means for heating a fluid in an area surrounding the heating means; two parallel temperature sensing elements positioned such that the fluid heated by the heating means moves across the two temperature sensing elements in free convection; and circuit means connected to the temperature sensing elements for determining acceleration, position, velocity or inclination based on the effect of acceleration on the free convection of the fluid in the area surrounding the heating means, wherein the heating means are the two temperature sensing elements.
Claim 23
Independent Claim
94 words
A device for sensing acceleration, position, velocity or inclination comprising: heating means for heating a fluid in an area surrounding the heating means; two parallel temperature sensing elements positioned such that the fluid heated by the heating means moves across the two temperature sensing elements in free convection; and circuit means connected to the temperature sensing elements for determining acceleration, position, velocity or inclination based on the effect of acceleration on the free convection of the fluid in the area surrounding the heating means, wherein the heating means are the two temperature sensing elements.
Claim 24
Independent Claim
98 words
A method for measuring acceleration or inclination comprising: providing an enclosure containing a fluid, two parallel temperature sensing elements and a heating means; heating the fluid within the enclosure with the heating means, wherein the heating means are the two temperature sensing elements; subjecting the enclosure to acceleration or inclination; and determining the acceleration or inclination of the enclosure by measuring a change in the temperature of the temperature sensing element, wherein the change in the temperature is caused by changes in the free convective flow within the enclosure due to the force of acceleration on the enclosure.
Claim 25
Independent Claim
98 words
A method for measuring acceleration or inclination comprising: providing an enclosure containing a fluid, two parallel temperature sensing elements and a heating means; heating the fluid within the enclosure with the heating means, wherein the heating means are the two temperature sensing elements; subjecting the enclosure to acceleration or inclination; and determining the acceleration or inclination of the enclosure by measuring a change in the temperature of the temperature sensing element, wherein the change in the temperature is caused by changes in the free convective flow within the enclosure due to the force of acceleration on the enclosure.
Claim 26
Dependent Claim
60 words
The method of claim 21, further comprising uniformly heating the two temperature sensing elements by free convection within the enclosure when the enclosure is not subject to the acceleration or inclination and wherein subjecting the enclosure to acceleration or inclination causes a change in free convection within the enclosure and a change in heating of the two temperature sensing elements.
References Cited (Backward Citations)
US2455394A
Cited
US2440189A
Cited
US3084557A
Cited
US3241374A
Cited
US3500691A
Cited
US3664196A
Cited
US3967178A
Cited
US4522062A
Cited
US4726227A
Cited
US4823461A
Cited
US4930349A
Cited
US4797661A
Cited
US4951507A
Cited
US5012676A
Cited
US5193392A
Cited
US5235237A
Cited
US5243861A
Cited
US5303589A
Cited
US5277064A
Cited
EP0664456A1
Cited
EP0674182A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-03 | 2000-06-03 | 2000-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-03 | 2004-06-03 | 2004-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-03 | 2008-06-03 | 2008-12-03 | $7700.00 | Window Closed / Lapsed |