US3668932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gravity gradient meter
Assignee: Raytheon Co
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Filing: 1970-12-04
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Granted: 1972-06-13
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Expires: 1990-12-04
Abstract
Abstract A resilient member is provided with first and second local gravity vector determining devices secured thereto and spaced thereon. Force means is attached to the bar to bend it. The output of the local gravity vector determining devices is connected to the force means so that the resilient member is bent so that each of the gravity vector determining devices is oriented so that the local gravity vector is parallel to its reference axis. The local gravity vector determining device is a bubble level operating under a flat surface, with electrodes determining bubble position. Four force motors positioned around a stiff central spring deflect the member.
Inventors
- 👤 Siegfried Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:11
CPC Classifications
G; G01; G01V; G01V7/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
168 words
A gravity gradient meter comprising: a resilient member having first and second mounting locations thereon spaced laterally with respect to a local gravity vector; first and second local gravity vector sensing devices respectively secured to said resilient member at said first and second spaced mounting locations thereon, each of said gravity vector sensing devices having an output when the local gravity vector is away from a reference axis of said gravity vector sensing device; connection means connected to receive the outputs from said first and second sensing devices for indicating the gravity gradient between said first and second local gravity sensing devices; and force means connected to said connection means for receiving signals corresponding to the sensing device outputs and connected to said resilient member for bending said resilient member in response to the outputs from said gravity vector sensing devices to bend said resilient member so that the reference axes of said first and second sensing devices are moved toward parallelism with their respective local gravity vectors.
Claim 2
Dependent Claim
168 words
A gravity gradient meter comprising: a resilient member having first and second mounting locations thereon spaced laterally with respect to a local gravity vector; first and second local gravity vector sensing devices respectively secured to said resilient member at said first and second spaced mounting locations thereon, each of said gravity vector sensing devices having an output when the local gravity vector is away from a reference axis of said gravity vector sensing device; connection means connected to receive the outputs from said first and second sensing devices for indicating the gravity gradient between said first and second local gravity sensing devices; and force means connected to said connection means for receiving signals corresponding to the sensing device outputs and connected to said resilient member for bending said resilient member in response to the outputs from said gravity vector sensing devices to bend said resilient member so that the reference axes of said first and second sensing devices are moved toward parallelism with their respective local gravity vectors.
Claim 3
Dependent Claim
47 words
The gravity gradient meter of claim 1 wherein each of said local gravity vector sensing devices comprises a liquid containing bubble chamber having a flat surface under which the bubble is located and electrodes in each of said bubble chambers detecting the position of the bubble therein.
Claim 4
Dependent Claim
50 words
The gravity gradient meter of claim 2 wherein said force means includes a plurality of force motors connected to said resilient member to bend said resilient member when said force motors are energized so that the surfaces under which the bubbles are positioned are normal to the local gravity vector.
Claim 5
Dependent Claim
54 words
The gravity gradient meter of claim 3 wherein said force means comprises at least five force points on said resilient member, including said force motors, so that said resilient member can be rocked, bent and twisted in response to the gradient between the local gravity vector at said two local gravity vector detecting devices.
Claim 6
Dependent Claim
24 words
The gravity gradient meter of claim 4 wherein said force means connected to said resilient member comprises a post, and four spaced force motors.
Claim 7
Dependent Claim
48 words
The gravity gradient meter of claim 5 wherein said force motors are positioned around said post, said post comprising a resilient post, said each of said force motors comprising a coil in a magnetic field so that variation in coil energization varies the force of said force motor.
Claim 8
Dependent Claim
48 words
The gravity gradient meter of claim 2 wherein power supply means is connected to each of said bubble chambers for applying an electrical signal to the liquid in each of said bubble chambers, so that said electrodes electrically detect the bubble position in each of said bubble chambers.
Claim 9
Dependent Claim
41 words
The gravity gradient meter of claim 7 wherein said electrodes are connected to an electric bridge, the electric input to said electric bridge being said power supply means and the electric output of said bridge being connected to said force means.
Claim 10
Dependent Claim
46 words
The gravity gradient meter of claim 8 wherein said power supply means is an oscillator and the output of said bridge is connected to a demodulator so that the demodulator output electric signal is a DC signal related to bubble position with respect to said electrodes.
Claim 11
Dependent Claim
85 words
The gravity gradient meter of claim 9 wherein there are first and second orthogonally arranged pairs of electrodes in one of said bubble chambers, with each of said pairs being respectively connected to first and second demodulators; said force means comprising first and second force motors connected to bend said resilient member, the output signals of said first and second demodulators being connected to both first and second adders and being algebraically added in different ways and connected to said first and second force motors.
Claim 12
Dependent Claim
104 words
The gravity gradient meter of claim 10 wherein there are two pairs of orthogonally arranged electrodes in said second bubble chamber, arranged on substantially the same orthogonal axes as the electrodes in said first bubble chamber; third and fourth demodulators respectively connected to each of said pairs and said second bubble chamber, the output of said third and fourth demodulators being connected to both third and fourth adders and being algebraically added in different ways; third and fourth force motors connected to bend said resilient member, the output of said third and fourth adders being respectively connected to said third and fourth force motors.
Claim 13
Dependent Claim
43 words
The gravity gradient meter of claim 11 wherein the inputs to said four force motors are connected to summing means and are summed together for producing a sum related to the gravity gradient between said first and second local gravity vector sensing devices.
References Cited (Backward Citations)
US2732717A
Cited
US3409993A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |