US4533382A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device and method for making and collecting fine metallic powder
Assignee: Toyota Motor Corp
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Filing: 1984-05-08
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Granted: 1985-08-06
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Expires: 2004-05-08
Abstract
Abstract Fine powder of a metal is made by vaporizing the metal in a vaporization chamber, mixing the metallic vapor with an inert carrier gas, and then adiabatically expanding the mixture through a nozzle, which preferably is a convergent-divergent nozzle. A jet flow from the nozzle is very rapidly cooled by this adiabatic expansion, which quickly condenses the metal vapor in the jet flow into very fine particles. Optionally the jet flow is directed against a metal powder collecting means, which may be a collection plate, but preferably is a bath of oil which entrains the particles and keeps them from agglomerating together by partially neutralizing their surface activity. Thus fine metal powder with particle diameters of the order of a few hundreds of angstroms can be economically produced.
Inventors
- 👤 Hirohisa Miura
- 👤 Hiroshi Sato
- 👤 Toshio Natsume
- 👤 Hidenori Katagiri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:25
CPC Classifications
B; B22; B22F; B22F9/00; B22F9/02; B22F9/12
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
70 words
A device for making fine metal powder, comprising: a vaporization chamber for producing metal vapor therein; means for heating said vaporization chamber; means for introducing a flow of inert gas into said vaporization chamber; an exit flow path from said vaporization chamber, comprising a nozzle therealong; a powder collection zone into which the flow out from said nozzle is directed; and means for evacuating gases from said powder collection zone.
Claim 2
Independent Claim
70 words
A device for making fine metal powder, comprising: a vaporization chamber for producing metal vapor therein; means for heating said vaporization chamber; means for introducing a flow of inert gas into said vaporization chamber; an exit flow path from said vaporization chamber, comprising a nozzle therealong; a powder collection zone into which the flow out from said nozzle is directed; and means for evacuating gases from said powder collection zone.
Claim 3
Dependent Claim
13 words
A device according to claim 1, wherein said nozzle is a convergent-divergent nozzle.
Claim 4
Dependent Claim
13 words
A device according to claim 1, wherein said nozzle is a convergent nozzle.
Claim 5
Dependent Claim
34 words
A device according to claim 1, further comprising means for collecting metal powder contained in said flow from said nozzle, said powder collecting means being located in said powder collection zone confronting said nozzle.
Claim 6
Dependent Claim
22 words
A device according to claim 4, wherein said powder collecting means comprises a plate on which said flow from said nozzle impinges.
Claim 7
Dependent Claim
12 words
A device according to claim 5, wherein said plate is water cooled.
Claim 8
Dependent Claim
17 words
A device according to claim 4, wherein said powder collecting means comprises a bath filled with oil.
Claim 9
Independent Claim
60 words
A method for making fine powder of a metal, comprising the steps of: producing vapor of said metal; mixing a flow of inert gas with said vapor of said metal to produce mixture gas; rapidly cooling said mixture gas by adiabatically expanding it by passing it through a nozzle; and collecting metal powder from a flow out from said nozzle.
Claim 10
Independent Claim
60 words
A method for making fine powder of a metal, comprising the steps of: producing vapor of said metal; mixing a flow of inert gas with said vapor of said metal to produce mixture gas; rapidly cooling said mixture gas by adiabatically expanding it by passing it through a nozzle; and collecting metal powder from a flow out from said nozzle.
Claim 11
Dependent Claim
13 words
A method according to claim 8, wherein said nozzle is a convergent-divergent nozzle.
Claim 12
Dependent Claim
13 words
A method according to claim 8, wherein said nozzle is a convergent nozzle.
Claim 13
Dependent Claim
31 words
A method according to claim 8, wherein said collection of metal powder from the flow out from said nozzle comprises the step of accumulating said metal powder on a collecting plate.
Claim 14
Dependent Claim
31 words
A method according to claim 8, wherein said collection of metal powder from the flow out from said nozzle comprises the step of accumulating said metal powder in an oil bath.
Claim 15
Dependent Claim
11 words
A method according to claim 8, wherein said metal is iron.
Claim 16
Dependent Claim
11 words
A method according to claim 8, wherein said metal is copper.
Claim 17
Dependent Claim
11 words
A method according to claim 8, wherein said metal is nickel.
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) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |