US3915006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic clinical thermometer
Assignee: Becton Dickinson and Co
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Filing: 1974-02-27
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Granted: 1975-10-28
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Expires: 1994-02-27
Abstract
Abstract An improved clinical thermometer is provided comprising an elongated tube of transparent material having closed top and bottom ends. A magnet is disposed adjacent the bore of the tube interposed between the ends dividing the tube into a first portion and a second portion. A magnetic fluid reservoir is defined in the tube first portion communicating with the bore and temperature indicating indicia is arranged alongside the tube second portion. A thermally expansible magnetic fluid of the type that experiences an increase in thixotropy or viscosity under the influence of the magnetic field is disposed in the reservoir.
Inventors
- 👤 Waldemar A Ayres
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:57
CPC Classifications
G; G01; G01K; G01K5/00; G01K5/02; G01K5/04; G01K5/12; G01K13/00; G01K13/20; G01K5/22
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
A thermometer comprising: an elongated tube of transparent material having a bore defined by a bottom end and a closed top end; a magnet disposed adjacent said bore interposed between said ends, said magnet separating said tube into a first portion and a second portion; a magnetic fluid reservoir in said tube first portion communicating with said bottom end of said bore; temperature indicating indicia arranged along said tube second portion; and a thermally expansible magnetic fluid disposed in said reservoir and in part of said bore, said fluid being of the type that experiences an increase in thixotropy or viscosity under the influence of a magnetic field.
Claim 2
Dependent Claim
108 words
A thermometer comprising: an elongated tube of transparent material having a bore defined by a bottom end and a closed top end; a magnet disposed adjacent said bore interposed between said ends, said magnet separating said tube into a first portion and a second portion; a magnetic fluid reservoir in said tube first portion communicating with said bottom end of said bore; temperature indicating indicia arranged along said tube second portion; and a thermally expansible magnetic fluid disposed in said reservoir and in part of said bore, said fluid being of the type that experiences an increase in thixotropy or viscosity under the influence of a magnetic field.
Claim 3
Dependent Claim
16 words
The thermometer in accordance with claim 1 wherein said tube second portion comprises a capillary tube.
Claim 4
Dependent Claim
21 words
The thermometer in accordance with claim 2 including an enlarged chamber portion of the capillary located closely adjacent to said magnet.
Claim 5
Dependent Claim
19 words
The thermometer in accordance with claim 1 wherein said magnet comprises a cylindrical hollow member disposed about said bore.
Claim 6
Dependent Claim
24 words
The thermometer in accordance with claim 1 wherein said fluid reservoir comprises a bulb section having a diameter greater than that of said bore.
Claim 7
Dependent Claim
16 words
The thermometer in accordance with claim 1 wherein a colorant is added to said magnetic fluid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |