US4827217A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low noise cryogenic apparatus for making magnetic measurements
Assignee: Biomagnetic Technologies Inc
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Filing: 1987-04-10
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Granted: 1989-05-02
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Expires: 2007-04-10
Abstract
Abstract Apparatus for performing sensitive magnetic measurements using cryogenically cooled instrumentation, wherein the instrumentation is separated from the bubbles present in a cryogenic cooling fluid. In one embodiment, the magnetic measurement instrumentation is placed in a tail piece joined by heat conducting bolts to a dewar containing a cryogenic fluid, and heat from the instrumentation is conducted to the cryogenic fluid heat sink by metallic strips reaching to the bolts. The cryogenic fluid does not contact the instrumentation directly, resulting in a significantly reduced level of noise in the instrumentation. The tail piece may also be evacuated to avoid pressure and temperature variations that may cause noise and affect the magnetic instrumentation.
Inventors
- 👤 Douglas N. Paulson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:36
CPC Classifications
F; F17; F17C; F17C3/00; F17C3/02; F17C3/08; F17C3/085; G; G01; G01R; G01R33/00; G01R33/02; G01R33/035; G01R33/0354; G01R33/0358; F17C2203/00; F17C2203/03; F17C2203/0391; F17C2203/06; F17C2203/0602; F17C2203/0612; F17C2203/0626; F17C2203/0631; F17C2203/0634; F17C2203/0658; F17C2203/0663; F17C2209/00; F17C2209/22; F17C2209/228; F17C2221/00; F17C2221/01; F17C2221/016; F17C2221/017; F17C2223/00; F17C2223/01; F17C2223/0146; F17C2223/0153; F17C2223/0161; F17C2270/00; F17C2270/05; F17C2270/0509; F17C2270/0527; F17C2270/0536
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
195 words
Cryogenic magnetic measurement apparatus, comprising: an insulated vessel whose walls are insulated to prevent the leakage of heat into the interior of said vessel, said vessel having an opening therein whereby a cryogenic fluid may be introduced into the interior of said vessel; an insulated tail piece joined to said insulated vessel and having walls that are insulated to prevent the leakage of heat into the interior of said tail piece, said tail piece being constructed of materials which do not interfere with the taking of magnetic measurements; a thermal connector between the interior of said tail piece and the interior of said insulated vessel, said thermal connector being heat conducting to conduct heat from the interior of said tail piece to the interior of said insulated vessel and providing a liquid-tight seal to prevent cryogenic liquid from leaking from said insulated vessel into said tail piece; magnetic measurement apparatus positioned within said tail piece; and means for conducting heat from said magnetic measurement apparatus to said thermal connector, so that in operation heat can be removed from said measurement apparatus to said thermal connector and thence to a cryogenic fluid contained within said vessel.
Claim 2
Dependent Claim
195 words
Cryogenic magnetic measurement apparatus, comprising: an insulated vessel whose walls are insulated to prevent the leakage of heat into the interior of said vessel, said vessel having an opening therein whereby a cryogenic fluid may be introduced into the interior of said vessel; an insulated tail piece joined to said insulated vessel and having walls that are insulated to prevent the leakage of heat into the interior of said tail piece, said tail piece being constructed of materials which do not interfere with the taking of magnetic measurements; a thermal connector between the interior of said tail piece and the interior of said insulated vessel, said thermal connector being heat conducting to conduct heat from the interior of said tail piece to the interior of said insulated vessel and providing a liquid-tight seal to prevent cryogenic liquid from leaking from said insulated vessel into said tail piece; magnetic measurement apparatus positioned within said tail piece; and means for conducting heat from said magnetic measurement apparatus to said thermal connector, so that in operation heat can be removed from said measurement apparatus to said thermal connector and thence to a cryogenic fluid contained within said vessel.
Claim 3
Dependent Claim
26 words
The apparatus of claim 1, wherein said thermal connector comprises metallic bolts extending from the interior said tail piece to the interior of said insulated vessel.
Claim 4
Dependent Claim
11 words
The apparatus of claim 2, wherein said metallic bolts include copper.
Claim 5
Dependent Claim
32 words
The apparatus of claim 1, wherein said means for conducting heat is a plurality of metal strips connected to said thermal connector at one end, and to said apparatus at the other.
Claim 6
Dependent Claim
11 words
The apparatus of claim 4, wherein said metal strips include copper.
Claim 7
Dependent Claim
16 words
The apparatus of claim 1, wherein said magnetic measurement apparatus includes a magnetic field sensing coil.
Claim 8
Dependent Claim
16 words
The apparatus of claim 1, wherein said magnetic measurement apparatus includes a superconducting quantum interference device.
Claim 9
Dependent Claim
14 words
The apparatus of claim 1, wherein said magnetic measurement apparatus includes a magnetization solenoid.
Claim 10
Dependent Claim
167 words
Cryogenic magnetic measurement apparatus, comprising: a vertical insulated dewar insulated from the external environment; an insulated, vertical, hollow tail piece insulated from the external environment, said tail piece being constructed of materials which do not interfere with the taking of magnetic measurements and being joined to said dewar but sealed therefrom so that fluid cannot flow from said dewar into said tail piece; a plurality of metallic bolts connecting said dewar and said tail piece, and extending from the interior said tail piece to the interior of said dewar to conduct heat from said tail piece to said dewar; magnetic measurement apparatus including a superconducting magnet, a magnetic field sensing coil, and a superconducting quantum interference device positioned within said tail piece; and a plurality of metal strips connected to said metallic bolts extending into said tail piece at one end, and to said measurement apparatus at the other, so that heat can be removed from said measurement apparatus to said bolts, and thence into said dewar.
Claim 11
Dependent Claim
167 words
Cryogenic magnetic measurement apparatus, comprising: a vertical insulated dewar insulated from the external environment; an insulated, vertical, hollow tail piece insulated from the external environment, said tail piece being constructed of materials which do not interfere with the taking of magnetic measurements and being joined to said dewar but sealed therefrom so that fluid cannot flow from said dewar into said tail piece; a plurality of metallic bolts connecting said dewar and said tail piece, and extending from the interior said tail piece to the interior of said dewar to conduct heat from said tail piece to said dewar; magnetic measurement apparatus including a superconducting magnet, a magnetic field sensing coil, and a superconducting quantum interference device positioned within said tail piece; and a plurality of metal strips connected to said metallic bolts extending into said tail piece at one end, and to said measurement apparatus at the other, so that heat can be removed from said measurement apparatus to said bolts, and thence into said dewar.
Claim 12
Dependent Claim
15 words
The apparatus of claim 9, wherein said magnetic measurement apparatus further includes a magnetization solenoid.
Claim 13
Dependent Claim
10 words
The apparatus of claim 9, wherein said bolts include copper.
Claim 14
Dependent Claim
11 words
The apparatus of claim 9, wherein said metal strips include copper.
References Cited (Backward Citations)
US3369174A
Cited
US3980076A
Cited
US4071815A
Cited
US4437064A
Cited
US4523147A
Cited
US4646025A
Cited
US4689559A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-01 | 1992-10-31 | 1993-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-01 | 1996-10-31 | 1997-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-01 | 2000-10-31 | 2001-05-02 | $7700.00 | Window Closed / Lapsed |