US3222569A

US3222569A - Apparatus and method for generating high-intensity light

Info

Publication number: US3222569A
Application number: US312573A
Authority: US
Inventors: John W Winzeler; James F Tucker
Original assignee: Giannini Scientific Corp
Current assignee: Giannini Scientific Corp
Priority date: 1961-05-22
Filing date: 1963-09-30
Publication date: 1965-12-07
Anticipated expiration: 1982-12-07

Description

Dec. 7, 1965 J. W. WINZELER ETAL APPARATUS AND METHOD FOR GENERATING HIGH-INTENSITY LIGHT GAS SOURCE CURRENT SOURCE 1 39 CURRENT 5a SOURCE 1 38 F G. 2

GAS SOURCE I 23 CURRENT SOURCE 35 F l G. 3

CURRENT SOURCE as f" l 64 540 JOHN w. WINZEILER L JAMES F. TUCKER INVENTORS BY 3s ATTORNEY United States Patent 11 Claims. (Cl. 315-111) This invention relates to an apparatus and method for generating a very intense light. The present application is a division of our copending patent application Serial No. 111,763, filed May 22, 1961, for an Apparatus and Method for Generating Heat and Light.

An object of the invention is to provide an apparatus and method for generating an extremely intense light which may be employed as a light source for numerous purposes.

Another object is to provide a highly eflicient light source and method characterized by the maintenance of an arc in a chamber through which gas is continuously circulated, in combination with special mirror means which at'least partially defines said chamber and which reflects light from said are to a window in the chamber wall.

These and other objects and advantages of the invention will be more fully set forth in the following specification and claims, considered in connection with the attached drawing to which they relate.

In the drawing:

FIGURE 1 is a schematic longitudinal sectional view illustrating one form of apparatus for generating an intense light;

FIGURE 2 is a transverse section taken on line 2-2 of FIGURE 1, showing the reflector and window for the light; and

FIGURE 3 is a schematic longitudinal central sectional view corresponding to FIGURE 1 but illustrating a different manner of supplying current to the various electrodes.

Referring first to the embodiment of FIGURES 1 and 2, an electrical plasma-jet torch is indicated generally at and has a non-consumable metal nozzle electrode 11 formed with an elongated cylindrical passage or opening 12. The upper end of passage 12 communicates with a cylindrical gas vortex chamber 13 having a frustoconical central portion or extension. The frustoconical wall 14 of such central portion or extension merges, at its narrow end, with the wall of passage 12.

The non-consumable metal back electrode 16 of the illustrated torch is conical in shape, the cone angle corresponding generally to that of wall 14. The tip of the back electrode is disposed in the frustoconical extension of vortex chamber 13, being spaced from wall 14 to form a frustoconical channel therebetween. The main body of the back electrode is disposed in the main or relatively large portion of vortex chamber 13, and has a radial flange 17 the peripheral wall of which is cylindrical in shape.

Flange 17 seats sealingly against the bottom of an inverted metal cup 18. The side wall of cup 18 is telescoped into a generally tubular end portion 19 of nozzle electrode 11, there being an insulating sleeve 21 provided between the cup wall and the tubular portion 19 in order to maintain the nozzle and back electrodes insulated from each other.

The internal surface of the cup side wall, and the exposed interior surface of insulating sleeve 21, are flush with each other and form the cylindrical wall of vortex chamber 13. Such cylindrical wall has a diameter sub- 3,222,569 Patented Dec. 7, 1965 stantially greater than the cylindrical wall of flange 17, in order to permit introduction of gas therebetween as will next be described.

Gas is introduced into chamber 13 from a suitable gas source which is represented schematically at 22. The gas conduit 23 from source 22 communicates tangentially with chamber 13 at a point located radially outwardly from flange 17. A suitable gas is thus introduced tangentially so that it will flow vortically around the back electrode 16. The gas then flows vortically and helically through the channel around the tip of the back electrode, and then fiows vortically and helically through nozzle passage 12.

The nozzle electrode 11 is formed with an annular cooling chamber 24 around the nozzle passage and also around wall 14. Water is passed through such chamber, and through a cooling chamber 26 in back electrode 16, by means of various conduits which are indicated at 27.

Mounted coaxially of nozzle electrode 11, in spaced relationship from the lower end thereof, is an additional non-consumable electrode 28 of annular shape. Such electrode, which may be formed of copper, tungsten or the like, has an opening 29 the diameter of which corresponds generally to that of the nozzle passage 12 with which it is registered. The additional electrode 28, which is insulated from the nozzle as will be described, is formed with an annular coolant chamber 32 through which water is passed by means of conduits 33.

A first current source 35 is connected through

leads

36 and 37, respectively, to the cup 18 and to nozzle electrode 11. Since the current in cup 18 flows through the adjacent back electrode to the tip thereof, an electric arc may thus be maintained in passage 12 between the tip of back electrode 16 and the wall of the passage 12. The current source 35 may be a source of either DC. or AC, preferably D.C. so that continuous ionization takes place, and should be adapted to deliver relatively large currents although not necessarily as large as those delivered by a second current source which is indicated at 38.

The second source 38 is connected, through leads 39 and 40, respectively, between the additional electrode 28 and the nozzle 11. The second source 38 is adapted to deliver extremely large currents and may comprise a DC. source or an AC. source, either single or multi-phase. Furthermore, the second source may comprise a circuit (such as containing a capacitor or bank thereof) adapted to deliver a large pulse of current at predetermined time intervals.

A chamber 57 is defined between the

electrodes

11 and 28, by means of a tubular insulating element 58 which is fixedly connected between the peripheral portions of the electrodes. Element 58 may be formed entirely of quartz or other suitable light-transmissive material, or else it may comprise an opaque ceramic insulator 59 having a quartz window 61 through which light is beamed by a reflector 62 next to be described.

Element 62 is illustrated as comprising a parabolic reflector the focal axis of which is coincident with the jet 42 of plasma or hot gas which emanates from passage 12. Element 62 is so constructed and mounted, for example by means of suitable electrical insulators, that it will not create a short circuit between

electrodes

11 and 28. The end edges of the parabola are sealingly associated at 63 with the ends of window 61, thereby defining a subchamber 64 around the reflector 62 and which is sealed from the portion of chamber 57 through which the jet 42 passes. A suitable coolant may be passed through sub-chamber 64 around the reflector 62 and which is sealed from the portion of chamber 57 through which the jet 42 passes. A suitable coolant may be passed through sub-chamber 64 by means of conduits indicated at 66 in FIGURE 2.

In performing the method with the embodiment of FIGURES 1 and 2, the electrical plasma-jet torch 10 is employed to generate the jet 42 which passes through the chamber 57 and through the opening 29 in electrode 28. The current source 38 is then ap lied to maintain an extremely high-current electric are through the jet 42 between

electrodes

11 and 28. The resulting combination are and jet 42 is an intense light source, sothat the beam reflected from the parabolic reflector 62 and transmitted through window 61 is exceedingly powerful.

The light may be employed for a wide variety of purposes, for example as a search light, spectroscopic light, etc. The gas employed may be varied in accordance with the type of light which is desired. Such gas may comprise argon or xenon, for example. Nitrogen may also be employed.

Embodiment FIGURE 3 In the embodiment of FIGURE 3, the current source 38 is connected between the additional electrode 28 and the back electrode 16, there being no connection between electrode 28 and electrode 11. Thus, the lead 39 of the previous embodiments is omitted and is replaced by the lead 67 from the current source to the back electrode 16. Alternatively, the current source connected between elements 16 and 28 may be additional to the current sources shown in FIGURE 1.

In the operation of the embodiment of FIGURE 3, the current source 35 is first applied (after application of the gas and water sources) to maintain an arc in passage 12 between electrode 16 and electrode 11. The second current source 38 is then applied to maintain an are between back electrode 16 and additional electrode 28, such are passing through the passage 12 and also through chamber 57. The portion of the arc in chamber 57 is employed as a light source, as previously described.

The current source 38 may be a multi-phase A.C. source or a pulse source such as one employing a capacitor discharge. It may also, as indicated, be a DC. source.

Various embodiments of the present invention, in addition to what has been illustrated and described in detail, may be employed without departing from the scope of the accompanying claims.

We claim:

1. A source of high-intensity light, which comprises means to define a chamber having an outlet opening therefrom,

window means to transmit light out of said chamber,

means including a first electric arc to introduce ionized gas into said chamber for discharge out said outlet opening, and

means to maintain a second and separate electric are through said ionized gas in said chamber to thereby create an intense light.

2. The invention as claimed in claim 1, in which reflector means are disposed in said chamber to collect light from said second arc and transmit the same through said window means.

3. Apparatus for generating a high-intensity light, comprising an electrical plasma-jet torch having a back electrode and a nozzle electrode,

means to maintain a first are between said back electrode and said nozzle electrode,

wall means to define a chamber communicating with the nozzle opening in said nozzle electrode,

said chamber having an outlet opening therefrom, means to pass gas through said torch and said nozzle opening for ionization by said first arc,

said gas passing through said chamber and out said outlet opening,

means to maintain a second and high-current arc in said chamber through said ionized gas and between said nozzle electrode and an additional electrode having at least a portion disposed in said chamber, and

window means to transmit light from said second are through said wall means defining said chamber.

4. A source of light, comprising an electrical plasma-jet torch having a back electrode and a nozzle electrode,

wall means to define a chamber communicating with the nozzle opening in said nozzle electrode and having a discharge opening therefrom,

said wall means including a window adapted to transmit light out of said chamber,

means including a first power source to maintain an are between said nozzle electrode and back electrode,

means to pass gas between said back electrode and nozzle electrode and into said chamber,

said gas being ionized by said arc, and

means including a second and separate power source connected between said nozzle electrode and an electrically-conductive portion of said wall means to maintain a high-current electric arc in said chamber and thus generate light for transmission through said window,

said electrically-conductive portion of said wall means being spaced and insulated from said nozzle electrode and encompassing said discharge opening.

5. Means to generate a high-intensity light, which comprises an electrical plasma-jet torch having a back electrode and a nozzle electrode,

means to introduce gas tangentially into said torch for vortical flow around the axis of said back electrode and thence through the nozzle opening in said nozzle electrode,

means including a first current source to maintain an electric arc between said back electrode and said nozzle electrode to thereby eflect ionization of said wa ll ineans to define a chamber communicating with said nozzle opening and having a discharge opening therefrom,

said wall means including a light-transmissive window, and

means including a second current source independent of said first current source to generate an additional are between said back electrode and an electricallyconductive portion of said wall means,

said electrically-conductive portion of said wall means being spaced and insulated from said nozzle electrode,

a portion of said additional are passing through said chamber to generate light for transmission out said window.

6. A method of providing a high-intensity light, which comprises employing an electrical plasma-jet torch to direct a stream of plasma to the vicinity of an additional electrode, maintaining a high-current are through said plasma and externally of said torch between said additional electrode and an electrode other than the back electrode of said torch, and transmitting the light generated by said high-current arc to a desired area of utilization. 7. Apparatus for generating a high-intensity light, which comprises wall means to define a chamber,

said wall means having formed therethrough an inlet opening into said chamber and an outlet opening from said chamber,

a portion of said wall means being transparent whereby to transmit light out of said chamber,

another portion of said wall means having on the interior thereof a reflector surface,

said reflector surface being shaped to reflect through said transparent portion of said wall means light received from a predetermined region of said chamber, electrode means to maintain a high-current electric arc in said chamber at said predetermined region thereof,

means to supply a high current to said electrode means to maintain an arc therebetween,

means to introduce a gas continuously through said inlet opening into said chamber, and

means to discharge said gas continuously through said outlet opening from said chamber.

8. The invention as claimed in claim 7, in which said are extends between said inlet opening and said outlet opening.

9. The invention as claimed in claim 7, in which said gas is selected from a group consisting of xenon, argon and nitrogen.

10. The invention as claimed in claim 7, in which said reflector surface is parabolic in shape, and in which said predetermined region of said chamber is at the focal region of said reflector surface.

11. A high-intensity light source, which comprises a reflector element which is curved in such manner that one side thereof is generally convex and the other side thereof is generally concave,

said concave side of said reflector element being reflective, first wall means cooperating with said concave side of said reflect-or element to define an arc chamber,

at least a portion of said first wall means being transparent whereby to transmit light out of said are chamber, second wall means cooperating with said convex side of said reflector element to define a coolant chamber, means to pass a coolant continuously through said coolant chamber, means to pass a gas continuously through said arc chamber, and means to maintain in said are chamber at a predetermined region thereof a high current electric are,

said predetermined region being so located that light generated by said are will be reflected by said reflector element to and through said transparent portion of said first wall means.

References Cited by the Examiner UNITED STATES PATENTS 2,856,532 10/1958 Martoma 313230 X 3,172,000 3/ 1965 Rosener et al. 3 1323l FOREIGN PATENTS 646,015 6/1960 Canada.

GEORGE N. WESTBY, Primary Examiner.

Claims

3. APPARATUS FOR GENERATING A HIGH-INTENSITY LIGHT, COMPRISING AN ELECTRICAL PLAMA-JET TORCH HAVING A BACK ELECTRODE AND A NOZZLE ELECTRODE, MEANS TO MAINTAIN A FIRST ARC BEWTWEEN SAID BACK ELECTRODE AND SAID NOZZLE ELECTRODE, WALL MEANS TO DEFINE A CHAMBER COMMUNICATING WITH THE NOZZLE OPENING IN SAID NOZZLE ELECTRODE, SAID CHAMBER HAVING AN OUTLET OPENING THEREFROM, MEANS TO PASS GAS THROUGH SAID TORCH AND SAID NOZZLE OPENING FOR IONIZATION BY SAID FIRST ARC, SAID GAS PASSING THROUGH SAID CHAMBER AND OUT SAID OUTLET OPENING, MEANS TO MAINTAIN A SECOND AND HIGH-CURRENT ARC IN SAID CHAMBER THROUGH SAID IONIZED GAS AND BETWEEN SAID NOZZLE ELECTRODE AND AN ADDITIONAL ELECTRODE HAVING AT LEAST A PORTION DISPOSED IN SAID CHAMBER, AND WINDOW MEANS TO TRANSMIT LIGHT FROM SAID SECOND ARC THROUGH SAID WALL MEANS DEFINING SAID CHAMBER.