US3604889A
Expired / Lapsed
US
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Plasma-generating method and means
Assignee: ADVANCED ROBOTICS Corp
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Filing: 1969-05-08
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Granted: 1971-09-14
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Expires: 1989-05-08
Abstract
Abstract An inert gas welding torch is used to create plasma by directing one or more discrete high velocity jet gas streams into a welding arc between the electrode and the workpiece. The plasma stream is controllable with regard to energy content or location by varying the amount or direction of the inert gas flow. The plasma stream is insensitive to variations of arc length, and permits abnormally high current densities in the electrode. When used with consumable electrodes, the invention is useful for casting as well as for deep welding heavy plate materials in a single pass.
Inventors
- 👤 Roderick Rohrberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:03
CPC Classifications
H; H05; H05H; H05H1/00; H05H1/24; H05H1/26; B; B23; B23K; B23K10/00; B23K10/02; H05H1/32; H05H1/34; H05H1/341; H05H1/3421; H05H1/3463; H05H1/3478
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
109 words
In a plasma-generating torch adapted to receive a supply of ionizing gas from an external source, an elongate electrode having a distal end protruding from said torch, circuit means connecting said torch to an external source of electrical power for creating an electrical arc in space beyond said distal end and completely outside said torch, aperture means in said torch for providing at least one jet of said ionizing gas angularly directed toward said arc to intersect with said arc external of said torch and having a substantially uniform flow direction angularly related to the long axis of said elongate electrode and of sufficient velocity to penetrate said arc.
Claim 2
Dependent Claim
109 words
In a plasma-generating torch adapted to receive a supply of ionizing gas from an external source, an elongate electrode having a distal end protruding from said torch, circuit means connecting said torch to an external source of electrical power for creating an electrical arc in space beyond said distal end and completely outside said torch, aperture means in said torch for providing at least one jet of said ionizing gas angularly directed toward said arc to intersect with said arc external of said torch and having a substantially uniform flow direction angularly related to the long axis of said elongate electrode and of sufficient velocity to penetrate said arc.
Claim 3
Dependent Claim
47 words
The structure set forth in claim 1 above, wherein: said aperture means comprises a plurality of apertures symmetrically arranged about said electrode proximate said distal end and oriented to direct a plurality of jets of said ionizing gas convergingly toward each other and directly into said arc.
Claim 4
Dependent Claim
32 words
The structure set forth in claim 2 above, further including: a plenum chamber in said torch adapted to receive said ionizing gas under pressure and to release said gas through said apertures.
Claim 5
Dependent Claim
65 words
The structure set forth in claim 3 above, wherein: said electrode protrudes from said chamber through a hole slightly larger in cross section than the cross-sectional size of said electrode, whereby some of said gas exits from said chamber through an annular gap formed between said hole and said electrode in an amount sufficient to prevent formulation of a center vortex by said converging jets.
Claim 6
Dependent Claim
32 words
The structure set forth in claim 4, above, including in addition thereto: a gas cup means surroundIng said electrode for providing a protecting gas shield around said converging jets and said arc.
Claim 7
Dependent Claim
62 words
The structure set forth in claim 5 above, wherein: said gas cup means is formed with an annular cavity therein having two concentric, substantially cylindrical walls, said walls having threaded connection with two removal rings in spaced-apart relationship, each of said rings separately engaging one of said walls to form an annular gap between said rings through which said shielding gas flows.
Claim 8
Independent Claim
66 words
A method for generating a stream of ionized gas, comprising: striking an arc between a welding torch electrode and a workpiece surface with said arc completely external of said torch, and forcefully directing at least one jet stream of ionizable gas to intersect with said arc along a path completely external of said torch and angularly disposed to the direction of current flow in said arc.
Claim 9
Independent Claim
66 words
A method for generating a stream of ionized gas, comprising: striking an arc between a welding torch electrode and a workpiece surface with said arc completely external of said torch, and forcefully directing at least one jet stream of ionizable gas to intersect with said arc along a path completely external of said torch and angularly disposed to the direction of current flow in said arc.
Claim 10
Dependent Claim
28 words
The method set forth in claim 7 above, further including: simultaneously providing a separate flow of said gas around said arc to shield the same from surrounding atmosphere.
Claim 11
Dependent Claim
49 words
The method set forth in claim 8 above further including: moving said electrode relative to said workpiece surface, and varying flow rate of said jet stream and the amplitude of current in said arc whereby welding heat is applied by said arc instead of said stream of ionized gas.
Claim 12
Dependent Claim
109 words
A plasma-generating system, comprising: a source of electrical current, a pair of plasma nozzles in spaced-apart mutual proximity, an electrode in each of said plasma nozzles, each of said electrodes disposed to form an electrical arc substantially entirely beyond the distal end of said nozzles electrical connection means between said current source and said electrodes for passing said current in an electrical arc from one of said electrodes to the other of said electrodes, and means for directing at least one jet of inert ionizable gas angularly into said arc to intersect with said arc and with a sufficient velocity to penetrate said arc and to generate said plasma.
Claim 13
Dependent Claim
109 words
A plasma-generating system, comprising: a source of electrical current, a pair of plasma nozzles in spaced-apart mutual proximity, an electrode in each of said plasma nozzles, each of said electrodes disposed to form an electrical arc substantially entirely beyond the distal end of said nozzles electrical connection means between said current source and said electrodes for passing said current in an electrical arc from one of said electrodes to the other of said electrodes, and means for directing at least one jet of inert ionizable gas angularly into said arc to intersect with said arc and with a sufficient velocity to penetrate said arc and to generate said plasma.
Claim 14
Dependent Claim
31 words
The structure set forth in claim 10 above, wherein: said pair of electrodes comprises a first stationary electrode of elongate form, and a second electrode movable relative to said first electrode.
Claim 15
Dependent Claim
29 words
The structure set forth in claim 10, above, wherein: a workpiece is positioned between said two electrodes and in spaced relationship therewith, whereby said arc penetrates through said workpiece.
Claim 16
Dependent Claim
19 words
The structure set forth in claim 10 above, wherein: both said electrodes are positioned on one side of workpiece.
Claim 17
Dependent Claim
118 words
In a plasma-generating torch adapted to receive a supply of ionizing gas from an external source, an elongate consumable electrode having a distal end protruding from said torch, circuit means connecting said torch to an external source of electrical power for creating an electrical arc in space proximate said distal end and completely outside said torch, aperture means in said torch for providing at least one jet of said ionizing gas having a single substantially uniform flow direction angularly related to the long axis of said elongate electrode to intersect with said arc external of said torch and of sufficient velocity to penetrate said arc, and feed means for feeding said electrode into said arc through said torch.
Claim 18
Dependent Claim
118 words
In a plasma-generating torch adapted to receive a supply of ionizing gas from an external source, an elongate consumable electrode having a distal end protruding from said torch, circuit means connecting said torch to an external source of electrical power for creating an electrical arc in space proximate said distal end and completely outside said torch, aperture means in said torch for providing at least one jet of said ionizing gas having a single substantially uniform flow direction angularly related to the long axis of said elongate electrode to intersect with said arc external of said torch and of sufficient velocity to penetrate said arc, and feed means for feeding said electrode into said arc through said torch.
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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) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |