US3596128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Excitation source for spectroscopic analysis
Assignee: Beckman Coulter Inc
•
Filing: 1969-05-01
•
Granted: 1971-07-27
•
Expires: 1989-05-01
Abstract
Abstract A plasma jet generator is composed of a swirl chamber, an anode within the swirl chamber, means for tangentially introducing a premixed atomized sample and an ionizing carrier gas into the chamber, an exit port for the generated plasma flame located opposite the anode, which exit port preferably has an electrically neutral border surrounding the port, and a cathode outside the chamber, offset from the plasma column and located at an angle to the axis of the anode so that the ionized gas is deflected to the cathode permitting spectrometric observation of any portion of the flame without interference from the ionized gas.
Inventors
- 👤 William G Elliott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:00
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/62; G01N21/71; G01N21/73; H; H05; H05H; H05H1/00; H05H1/24; H05H1/26; H05H1/32; H05H1/42
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
136 words
A plasma flame generator comprising: a. a chamber, one wall thereof having an orifice therein; b. an anode disposed in said chamber and locaTed opposite said orifice; c. means to introduce an atomized sample to be analyzed and an ionizing carrier gas into said chamber whereby a plasma flame is generated in the chamber and the plasma flame exits the orifice in a plasma column, said column aligned along an axis passing through the orifice and the anode; and d. a cathode located externally to and spaced from said chamber and at an angle to the axis of the plasma column, said cathode being offset from said plasma column whereby the plasma flame after exiting said chamber through the orifice is bent at an angle to the axis of the plasma column to contact said cathode.
Claim 2
Dependent Claim
136 words
A plasma flame generator comprising: a. a chamber, one wall thereof having an orifice therein; b. an anode disposed in said chamber and locaTed opposite said orifice; c. means to introduce an atomized sample to be analyzed and an ionizing carrier gas into said chamber whereby a plasma flame is generated in the chamber and the plasma flame exits the orifice in a plasma column, said column aligned along an axis passing through the orifice and the anode; and d. a cathode located externally to and spaced from said chamber and at an angle to the axis of the plasma column, said cathode being offset from said plasma column whereby the plasma flame after exiting said chamber through the orifice is bent at an angle to the axis of the plasma column to contact said cathode.
Claim 3
Dependent Claim
39 words
The device as defined in claim 1 wherein said anode is graphite, said orifice is an electrically neutral ring of graphite, and said cathode is tungsten and said cathode is substantially perpendicular to the axis of said plasma column.
Claim 4
Dependent Claim
21 words
The device as defined in claim 1 which includes means to introduce said sample and said gas tangentially into said chamber.
Claim 5
Dependent Claim
33 words
The device as defined in claim 1 which includes a second wall spaced apart from the wall having the orifice therein and wherein the walls of said chamber are uncooled and thermally conductive.
Claim 6
Dependent Claim
20 words
The device as defined in claim 1 wherein said sample introducing means includes an atomizer located externally to said chamber.
Claim 7
Dependent Claim
100 words
The device as defined in claim 5 wherein said atomizer comprises a mixing chamber and a trap chamber wherein a sample to be analyzed and an ionizing carrier gas are introduced under sufficient pressure to atomize said sample, orifice means for passing the contents of the mixing chamber into the trap chamber, means in said trap chamber for communicating with said plasma chamber located above the inlet to said trap chamber from said mixing chamber whereby any droplets are retained within said trap chamber and only atomized sample and carrier gas pass from said trap chamber to said plasma chamber.
Claim 8
Dependent Claim
76 words
The device as defined in claim 5 wherein said atomizer comprises a conical chamber; a nozzle for introducing into said conical chamber said sample and said ionizing gas under sufficient pressure to atomize said sample; means in opposed relationship to said nozzle for collecting relatively large droplets of said sample from the atomized mist, and means communicating with said plasma chamber from said conical chamber, whereby only highly atomized droplets are introduced into said plasma flame.
Claim 9
Dependent Claim
18 words
The device as defined in claim 1 wherein cooling means are associated with said anode and said cathode.
Claim 10
Dependent Claim
28 words
The device as defined in claim 1 wherein said orifice is an electrically neutral ring composed of a ceramic and constitutes substantially the entire wall of said chamber.
Claim 11
Dependent Claim
34 words
The device as defined in claim 1 wherein the second wall is the floor of said chamber and said floor is composed of a ceramic and the chamber includes sidewalls which are stainless steel.
Claim 12
Dependent Claim
29 words
The device as defined in claim 1 wherein said anode and cathode are connected to a power supply of about 25 to 50 volts at 2 to 10 amperes.
Claim 13
Independent Claim
142 words
A method for generating a curved plasma flame which comprises: a. introducing an atomized mixture of a sample to be analyzed and an ionizing gas into a chamber; b. applying a voltage to an anode and a cathode to generate a plasma flame, the anode disposed within the chamber and substantially in line with an exit orifice, and the cathode located external to the chamber and orifice and offset from said orifice; c. flowing the plasma flame through the orifice in the chamber; d. exiting the plasma flame from the orifice as a plasma column, said column substantially aligned with the axis passing through the anode and the orifice; and e. bending the plasma flame from the plasma column to engage the cathode an an angle to the axis of the plasma column and to a position offset from said plasma column.
Claim 14
Independent Claim
142 words
A method for generating a curved plasma flame which comprises: a. introducing an atomized mixture of a sample to be analyzed and an ionizing gas into a chamber; b. applying a voltage to an anode and a cathode to generate a plasma flame, the anode disposed within the chamber and substantially in line with an exit orifice, and the cathode located external to the chamber and orifice and offset from said orifice; c. flowing the plasma flame through the orifice in the chamber; d. exiting the plasma flame from the orifice as a plasma column, said column substantially aligned with the axis passing through the anode and the orifice; and e. bending the plasma flame from the plasma column to engage the cathode an an angle to the axis of the plasma column and to a position offset from said plasma column.
Claim 15
Dependent Claim
15 words
The method of claim 12 which includes introducing tangentially the atomized mixture into the chamber.
Claim 16
Dependent Claim
65 words
The method of claim 12 wherein the plasma flame exiting the orifice as a plasma column comprises an ionized gas and a sample in the form of atomic vapor and which includes: bending substantially all of the ionized gas from the plasma column to engage the cathode, and flowing the atomic vapor substantially in line with the axis passing through the anode and the orifice.
Claim 17
Dependent Claim
31 words
The method of claim 12 which includes: surrounding the plasma flame with cooling gases as it exits the orifice to define a second column of cooling gases surrounding the plasma column.
Claim 18
Dependent Claim
35 words
The method of claim 15 which includes: flowing the plasma flame and the surrounding column of cooling gases through a constricted orifice; and pinching the plasma as it flows through the orifice to prevent wandering.
Claim 19
Dependent Claim
11 words
The method of claim 12 wherein the carrier gas is argon.
Claim 20
Dependent Claim
21 words
The method of claim 12 wherein the carrier gas has a flow rate of 3 to 10 cubic feet per hour.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |