US4558218A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat pipe oven molecular beam source
Assignee: United States Department of Commerce
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Filing: 1984-08-01
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Granted: 1985-12-10
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Expires: 2004-08-01
Abstract
Abstract A heat pipe oven molecular beam source wherein a hollow porous metal, metalloid or ceramic body with at least one opening is nearly saturated with the working material and heated to just above the melting point of the working material, generating a thin liquid layer of the working material on the internal surface of the body. Material passing the length of the bore of the body without striking a wall will escape and form the beam. Material striking the liquid layer covering the inside of the body will condense and be conveyed by capillary action back to the closed end of the body.
Inventors
- 👤 Robert E. Drullinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:50
CPC Classifications
H; H05; H05H; H05H3/00; H05H3/02
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
66 words
A molecular beam source comprising: a porous substrate having a constant diameter central cavity with at least one opening to the exterior of the substrate; working material nearly saturating said substrate such that a thin liquid layer of said working material covers the surface of the central cavity; and means for maintaining the temperature of said substrate slightly above the melting point of said working material.
Claim 2
Dependent Claim
66 words
A molecular beam source comprising: a porous substrate having a constant diameter central cavity with at least one opening to the exterior of the substrate; working material nearly saturating said substrate such that a thin liquid layer of said working material covers the surface of the central cavity; and means for maintaining the temperature of said substrate slightly above the melting point of said working material.
Claim 3
Dependent Claim
29 words
The molecular beam source of claim 1, wherein said central cavity comprises an axial bore with two ends, the first end being closed and the second end being open.
Claim 4
Dependent Claim
45 words
The molecular beam source of claim 1, wherein the temperature means is disposed such that the temperature of said substrate away from said at least one opening is maintained at a temperature higher than the temperature of said substrate near said at least one opening.
Claim 5
Dependent Claim
26 words
The molecular beam source of claim 1, wherein said substrate is thicker away from said at least one opening than near said at least one opening.
Claim 6
Dependent Claim
30 words
The molecular beam source of claim 1, wherein the pores of said porous substrate are larger away from said at least one opening than near said at least one opening.
Claim 7
Dependent Claim
27 words
The molecular beam source of claim 1, wherein said substrate is selected from the group consisting of tungsten, molybdenum, stainless steel, nickel, copper and the alumina silicates.
Claim 8
Dependent Claim
60 words
The molecular beam source of claim 1, wherein said working material is cesium, said substrate is sintered tungsten, and said temperature means is disposed such that the temperature of said substrate near said single opening is maintained at about 30° C. and the temperature of said substrate away from said single opening is maintained between about 80° and 120° C.
Claim 9
Dependent Claim
20 words
The molecular beam source of claim 2, wherein the axial length of said bore is substantially greater than its diameter.
Claim 10
Dependent Claim
74 words
A molecular beam source comprising: a porous wick with a non-porous external casing, said wick having a constant diameter axial bore extending from a first end of said wick to a second end of said wick; an opening at said second end opening said bore to the exterior of said wick and casing; source material nearly saturating said wick; a heat source for maintaining the temperature of said source material above its melting point.
Claim 11
Dependent Claim
74 words
A molecular beam source comprising: a porous wick with a non-porous external casing, said wick having a constant diameter axial bore extending from a first end of said wick to a second end of said wick; an opening at said second end opening said bore to the exterior of said wick and casing; source material nearly saturating said wick; a heat source for maintaining the temperature of said source material above its melting point.
Claim 12
Dependent Claim
41 words
The molecular beam source of claim 9, wherein said heat source is so disposed as to maintain the temperature of said second end just above said melting point, while maintaining the temperature of said first end further above said melting point.
Claim 13
Dependent Claim
23 words
The molecular beam source of claim 9, wherein the external diameter of said wick tapers from said first end to said second end.
Claim 14
Dependent Claim
24 words
The molecular beam source of claim 9, wherein the pores of said wick are larger at said first end than at said second end.
Claim 15
Dependent Claim
20 words
The molecular beam source of claim 9, wherein said source material is a metal, alkali metal, organic compound or water.
Claim 16
Dependent Claim
27 words
The molecular beam source of claim 9, wherein said wick is selected from the group consisting of sintered tungsten, sintered molybdenum, sintered stainless steel and cloth gauze.
Claim 17
Dependent Claim
73 words
The process of generating a molecular beam, comprising: providing a porous substrate having a constant diameter central axial bore, said bore being closed at one end and open at the other with the exterior of said substrate in a non-porous casing; nearly saturating said substrate with the material of which the beam is to be comprised; maintaining the temperature of said substrate and said material slightly above the melting point of said material.
Claim 18
Dependent Claim
73 words
The process of generating a molecular beam, comprising: providing a porous substrate having a constant diameter central axial bore, said bore being closed at one end and open at the other with the exterior of said substrate in a non-porous casing; nearly saturating said substrate with the material of which the beam is to be comprised; maintaining the temperature of said substrate and said material slightly above the melting point of said material.
Claim 19
Dependent Claim
38 words
The process of claim 15, further comprising: raising the temperature of said substrate and said material at said closed end further above said melting point, while maintaining the temperature at said open end slightly above said melting point.
Claim 20
Dependent Claim
40 words
The process of claim 15, wherein said porous substrate is provided by drilling said axial bore into a block of the material of which said substrate is comprised; and etching the surface of the bore to re-open the pores therein.
Claim 21
Dependent Claim
25 words
The process of claim 17, further comprising: shaping the outside of said block such that it tapers from said closed end to said open end.
References Cited (Backward Citations)
US3058023A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-09 | 1989-06-10 | 1989-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-09 | 1993-06-10 | 1993-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-09 | 1997-06-10 | 1997-12-10 | $7700.00 | Window Closed / Lapsed |