US3736937A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cryogenic tool
Assignee: Raytheon Co
•
Filing: 1972-06-08
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Granted: 1973-06-05
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Expires: 1992-06-08
Abstract
Abstract The external surface of the working tip of the cryogenic tool is applicable to any point where cooling is desired, for example, affected tissue in cryosurgery. An inner surface of the tip is supplied with a cryogenic liquid thru a capillary active surface from a reservoir. The boiled off cryogen vapor exits from the cryogenic tool to atmosphere.
Inventors
- 👤 A Basiulis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:37
CPC Classifications
A; A61; A61B; A61B18/00; A61B18/02; A61B2018/00053; A61B2018/00059; A61B2018/00089; A61B2018/00095; A61B90/00; A61B90/08; A61B2090/0813; A61B2218/00; A61B2218/001; A61B2218/002; F; F25; F25B; F25B19/00; F25B19/005
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
242 words
A cryogenic tool comprising: a reservoir for the storage of cryogenic liquid which boils at sub-atmospheric temperatures, a lining of capillary active material within said reservoir so that when some of said reservoir lining is in contact with cryogenic liquid, the entire lining is wet with cryogenic liquid; a tubular duct extending from said reservoir, said duct having a capillary active surface therein, and having a reservoir end and a working end, said reservoir end of said tubular duct being open to the atmosphere for discharge of cryogen vapor therefrom to the atmosphere, a liquid cryogen opening between said reservoir and the interior of said duct intermediate its end so that said lining of capillary active material in said reservoir is in contact with the active capillary surface in said duct and can feed liquid cryogen through said opening into the interior of said duct to feed liquid cryogen to the active capillary surface in said duct so that the active capillary surface within said duct can feed liquid cryogen toward the working end of said duct; a working tip on the end of said duct and an evaporative surface within said duct in thermal communication with said working tip, said evaporative surface being fed with liquid cryogen from the capillary active surface in said duct so that liquid cryogen is fed to the evaporative surface whereby evaporative cooling takes place and the cryogen vapor returns through said duct to the atmosphere.
Claim 2
Dependent Claim
242 words
A cryogenic tool comprising: a reservoir for the storage of cryogenic liquid which boils at sub-atmospheric temperatures, a lining of capillary active material within said reservoir so that when some of said reservoir lining is in contact with cryogenic liquid, the entire lining is wet with cryogenic liquid; a tubular duct extending from said reservoir, said duct having a capillary active surface therein, and having a reservoir end and a working end, said reservoir end of said tubular duct being open to the atmosphere for discharge of cryogen vapor therefrom to the atmosphere, a liquid cryogen opening between said reservoir and the interior of said duct intermediate its end so that said lining of capillary active material in said reservoir is in contact with the active capillary surface in said duct and can feed liquid cryogen through said opening into the interior of said duct to feed liquid cryogen to the active capillary surface in said duct so that the active capillary surface within said duct can feed liquid cryogen toward the working end of said duct; a working tip on the end of said duct and an evaporative surface within said duct in thermal communication with said working tip, said evaporative surface being fed with liquid cryogen from the capillary active surface in said duct so that liquid cryogen is fed to the evaporative surface whereby evaporative cooling takes place and the cryogen vapor returns through said duct to the atmosphere.
Claim 3
Dependent Claim
32 words
The cryogenic tool of claim 1 wherein a supplementary working tip is positioned over said working tip, in thermal communication therewith, so that the supplementary working tip can be removed and interchanged.
Claim 4
Dependent Claim
29 words
The cryogenic tool of claim 1 wherein said working tip is removable from the working end of said duct so that said working tip can be removed and replaced.
Claim 5
Dependent Claim
20 words
The cryogenic tool of claim 3 wherein said working tip is engaged upon said duct by screw thread engagement therebetween.
Claim 6
Dependent Claim
33 words
The cryogenic tool of claim 1 wherein said evaporative surface in thermal communication with said working tip is substantially conical surface with its point directed away from said working tip, toward said duct.
Claim 7
Dependent Claim
23 words
The cryogenic tool of claim 5 wherein said capillary active interior surface of said duct is in physical contact with said evaporative surface.
Claim 8
Dependent Claim
31 words
The cryogenic tool of claim 6 wherein a vapor tube extends from adjacent said working tip through said duct into said reservoir, for the return of cryogen vapor to said reservoir.
Claim 9
Dependent Claim
38 words
The cryogenic tool of claim 7 wherein said evaporative cone has a longitudinal groove in the surface thereof, and said vapor tube is engaged over said evaporative cone, said groove preventing sealing of said tube on said cone.
Claim 10
Dependent Claim
35 words
The cryogenic tool of claim 1 wherein said tip is an elongated tube of larger diameter than said duct, said tube tip having a substantial portion of its surface cooled by evaporation of cryogen therein.
Claim 11
Dependent Claim
35 words
The cryogenic tool of claim 9 wherein the capillary active material in said duct is in contact with capillary active material lining said tube tip to deliver liquid cryogen for evaporation within said tube tip.
Claim 12
Dependent Claim
15 words
The cryogenic tool of claim 10 wherein said tube tip has an insulated nose thereon.
Claim 13
Dependent Claim
28 words
The cryogenic tool of claim 1 wherein said capillary active material within said duct is a mass of stainless steel fibers sintered together to form a felt-like mass.
Claim 14
Dependent Claim
34 words
The cryogenic tool of claim 1 wherein said capillary active lining comprises a concentric annulus formed by a perforated tube substantially concentrically positioned within said duct so that there is a capillary space therebetween.
Claim 15
Dependent Claim
34 words
The cryogenic tool of claim 1 wherein said capillary active surface within said duct comprises a crescent annulus formed between a perforated tube non-concentrically positioned within said duct and the interior of said duct.
Claim 16
Dependent Claim
24 words
The cryogenic toOl of claim 1 wherein said capillary active surface comprises a plurality of channels longitudinally directed on the interior of said duct.
Claim 17
Dependent Claim
20 words
The cryogenic tool of claim 15 wherein a capillary active layer is positioned within said duct interiorly of said channels.
Claim 18
Dependent Claim
24 words
The cryogenic tool of claim 1 wherein said capillary active lining of said duct includes an artery in contact with the capillary active surface.
Claim 19
Dependent Claim
67 words
The cryogenic tool of claim 1 wherein a heater is positioned around said duct between said reservoir and said working tip so that when heat is applied to said duct by said heater, liquid cryogen flowing from said reservoir toward the working end of said duct is evaporated before it reaches the working end of said duct to stop cooling at the working end of said duct.
Claim 20
Dependent Claim
106 words
The cryogenic tool of claim 1 wherein a removable cap is positionable over the end of said duct within said reservoir, so that when said removable cap is away from said end of said duct, vapor can escape from said duct into said reservoir and liquid cryogen can flow through said feed opening toward said working end of said duct, and when said cap is positioned over the end of said duct within said reservoir, vapor pressure within said duct prevents liquid cryogen from passing from said reservoir through said feed opening to said duct, so that refrigeration at the working end of said duct ceases.
Claim 21
Dependent Claim
36 words
The cryogenic tool of claim 1 wherein a trap vessel is positioned to receive vapor from said reservoir and discharge it toward the atmosphere, said trap vessel inhibiting the flow of liquid cryogen to the atmosphere.
Claim 22
Dependent Claim
47 words
The cryogenic tool of claim 20 wherein said trap vessel comprises a tube positioned within said reservoir, a vapor inlet to said trap extending substantially half way into said trap tube, an outlet tube from said trap reservoir extending from said trap tube out of said reservoir.
Claim 23
Dependent Claim
43 words
The cryogenic tool of claim 1 wherein said reservoir has a substantially truncated conical fill opening therein, a cap detachably secured to said reservoir, a plug movably mounted with respect to said cap engaging in said fill opening, removably close said fill opening.
Claim 24
Dependent Claim
24 words
The cryogenic tool of claim 22 wherein said plug is resiliently urged with respect to said cap into closure engagement within said fill opening.
Claim 25
Dependent Claim
27 words
The cryogenic tool of claim 1 wherein a mass which is fluid at room temperature and is solid at cryogenic temperature is positioned on said working tip.
Claim 26
Dependent Claim
17 words
The cryogenic tool of claim 24 wherein said mass is enclosed in a polymer composition material bag.
Claim 27
Dependent Claim
41 words
The cryogenic tool of claim 25 wherein a metallic boss engages on said working tip and said bag engages around a portion of said bag so that said boss is in thermal communication with said mass and with said working tip.
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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) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |