Patent US3828571A successfully refreshed from Google Patents.
US3828571A
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Cover for microtome and ultramicrotome freezing chamber
Assignee: C Reichert Optische Werke AG
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Filing: 1973-09-05
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Granted: 1974-08-13
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Expires: 1993-09-05
Abstract
Abstract A transparent cover having a conical depression with an elliptical opening to control the passage of coolant gas from the freezing chamber of a microtome or ultramicrotome provides improved cooling with increased versatility and permits microtome techniques to be practiced heretofore not considered practical.
Inventors
- 👤 G Lechner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:37
CPC Classifications
G; G01; G01N; G01N1/00; G01N1/02; G01N1/04; G01N1/06; G01N1/28; G01N1/42
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
118 words
In a freezing chamber for a microtome or ultramicrotome having a cooling unit to absorb heat by the evaporation of a liquefied gas in an area proximate to the knife and specimen, the improvement comprising a cover for said chamber, said cover having an upper surface, a conical depression in said upper surface, said depression having a continuous depending sidewall and a lowermost edge defining a passage through said cover, said edge being spaced from said upper surface and being in a plane bisecting the plane of said upper surface at an angle less than about 15* whereby the flow of evaporating gas within said chamber displaces the atmosphere through said passage from the chamber without significant mixing.
Claim 2
Dependent Claim
118 words
In a freezing chamber for a microtome or ultramicrotome having a cooling unit to absorb heat by the evaporation of a liquefied gas in an area proximate to the knife and specimen, the improvement comprising a cover for said chamber, said cover having an upper surface, a conical depression in said upper surface, said depression having a continuous depending sidewall and a lowermost edge defining a passage through said cover, said edge being spaced from said upper surface and being in a plane bisecting the plane of said upper surface at an angle less than about 15* whereby the flow of evaporating gas within said chamber displaces the atmosphere through said passage from the chamber without significant mixing.
Claim 3
Dependent Claim
23 words
The improvement of claim 1 wherein said cover has a rectangular peripheral border, said conical depression said passage have major and minor axes.
Claim 4
Dependent Claim
11 words
The improvement of claim 2 wherein said major axes are coincident.
Claim 5
Dependent Claim
14 words
The improvement of claim 3 wherein said passage is egocentrically displaced within said depression.
Claim 6
Dependent Claim
38 words
The improvement of claim 4 wherein the ratio of the planar area of the chamber closed by said cover to the planar area of said depression to the planar area of said passage is about 1:0.5 : 0.2.
Claim 7
Dependent Claim
11 words
The improvement of claim 5 wherein said angle is about 10*.
Claim 8
Dependent Claim
32 words
The improvement of claim 6 wherein the distance between said lowermost edge and said upper surface varies continuously between a maximum and a minimum providing large and small portions of said sidewall.
Claim 9
Dependent Claim
20 words
The improvement of claim 7 wherein the large portion of said sidewall is intermediate said cooling unit and said passage.
Claim 10
Dependent Claim
14 words
The improvement of claim 8 wherein said chamber has a plurality of cooling units.
References Cited (Backward Citations)
US3462969A
Cited
US3495490A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |