US3319097A

US3319097A - High intensity-gas lamp with recirculation means

Info

Publication number: US3319097A
Application number: US445843A
Authority: US
Inventors: Gabriel M Giannini; Adriano C Ducati; Hubert C Sullivan
Original assignee: Giannini Scientific Corp
Current assignee: Giannini Scientific Corp
Priority date: 1965-03-25
Filing date: 1965-03-25
Publication date: 1967-05-09
Anticipated expiration: 1984-05-09

Description

y 1967 5. M. GiANNINI YETAL- 3,319,097

HIGH INTENSITY-GAS LAMP WITH RECIRCULATION MEANS Original Filed June 6. 1962 2 Sheets-Sheet 1 INVENTORS ease/e2 M a/a/v/w/v/ nae/4N0 6. 01/607/ z/z/afercz 52/44/140 United States Patent 3,319,097 I-HGH INTENSITY-GAS LAMP WITH RECIRCULATION MEANS Gabriel M. Giannini, llndio, Adriano C. Ducati, Santa Ana, and Hubert C. Sullivan, Riverside, Califi, assignors to Giannini Scientific Corporation, Amityville, N.Y., a cor oration of Delaware Continuation of application Ser. No. 200,584, June 6, 1962. This appiication Mar. 25, 1965, Ser. No. 445,843 3 Ciaims. (Cl. 313-12) This application is a continuation of application Ser. No. 200,584, filed June 6, 1962, for Lamp Apparatus and Method, now abandoned, which is a continuation-in-part of application Ser. No. 844,466, filed Oct. 5, 1959, for a Forced-Recirculation Lamp Apparatus, now abondoned.

This invention relates to an electric lamp apparatus and method incorporating means to effect circulation of gas for purposes including stabilization of an electric are.

An object of the present invention is to provide an improved apparatus and method for generating an extremely high-intensity light by means of an electric arc.

Another object is to provide an electric lamp device incorporating novel means to effect recirculation of gas to an electric arc.

Another object is to provide a novel electric lamp apparatus incorporating forced-recirculation means to recirculate gas which effects stabilization and constriction of an electric arc, and in which either the are or the heated gas is employed as a source of light.

A further object is to provide a lamp apparatus which is extremely effective and efiicient in operation, yet is very simple and compact in construction.

A further object is to provide a lamp apparatus incorporating neans to both clean and cool, in a highly effective manner, the light-transmissive wall of an arc chamber.

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 drawings to which they relate.

In the drawings:

FIGURE 1 is a schematic longitudinal central sectional view of a lamp apparatus constructed in accordance with a first embodiment of the invention;

FIGURE 2 is a transverse section taken on line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary longitudinal sectional view illustrating schematically the electromagnetic pump apparatus;

FIGURE 4 is a transverse schematic sectional view of the pump apparatus of FIGURE 3; and

FIGURE 5 is a schematic longitudinal central sectional view of a lamp apparatus constructed in accordance with a second embodiment of the invention.

Referring first to the embodiment of FIGURES 1-4, the apparatus is illustrated to comprise arcing elements and 11 between which a stabilized electric arc may be maintained, one of such elements (number 10) having an opening 12 therein so that plasma generate-d by the arc may be discharged. Transparent wall means 13 are provided to permit light emanating from the plasma to be transmitted to any desired region. Means 14 are provided to effect forced recirculation of a gas, such as mercury vapor, through the arc space between elements 10 and 11.

More specifically, the arcing element 10 is illustrated as comprising a generally tubular refractory metal insert adapted to protect the wall of the nozzle opening in the metal nozzle electrode 16 of an electrical plasma-jet torch. Arcing element 11, also a refractory metal insert, is located in the central portion of the generally disc-shaped metal back electrode 17 of the torch. Electrode 17 is mounted in nozzle electrode 16, which is generally cupshaped, in mutually-insulated relationship. The nozzle and

back electrodes

16 and 17 are shaped to define between arcing elements 10 and 11 an annular gas-pressure chamber 18 coaxial with the opening 12 in the nozzle insert.

A flanged body 19, formed of metal, is disposed rearwardly adjacent back electrode 17 and in electrical contact therewith. Both the body 19 and the back electrode 17 are insulated from the nozzle electrode 16 by means of suitable insulation indicated at 20. A retaining ring 21 is threaded into the nozzle electrode in order to maintain the parts in assembled relationship.

A suitable current source indicated schematically at 23, is connected to the nozzle electrode and to body 19 in order to effect conduction of current to the arcing elements 10 and 11.

Cooling chambers

24 and 25 are formed, respectively, adjacent arcing elements 10 and 11 in order to effect cooling thereof. Water may be passed continuously through the

cooling chambers

24 and 25 by means of

suitable conduits

26 and 27.

The chamber into which the plasma discharges when an arc is maintained between elements 10 and 11, and when gas is passed into chamber 18, has been given the reference numeral 29. Such chamber is partially defined by a wall means 31 shown as being generally tubular in shape and coaxial with nozzle opening 12. Wall means 31 may be formed of metal and may incorporate a cooling chamber 32 through which coolant water may be circulated. Chamber 29 is defined not only by the wall means 32 but also by the forward wall of nozzle electrode 16 and by the previously-indicated transparent wall means 13. The wall means 13 may comprise a lens which is mounted sealingly over the end of tubular wall 32 remote from the torch.

Proceeding next to a description of the forced-recirculation means 14, this is adapted to effect continuous discharge of mercury vapor from the chamber 29, and continuous introduction of mercury vapor at a relatively high pressure and velocity into the gas-pressure chamber 18. Means 14 is shown schematically in FIGURE 1 as comprising a conduit 33 connected to chamber 29 to effect flow of gas therefrom to a suitable condenser 34. Condenser 34- is connected to an electromagnetic pump 35, the arrangement being such that liquid mercury condensed in condenser 34 will be pumped by the pump 35 into a suitable vaporizer 36 where the liquid mercury is converted into mercury vapor.

The resulting mercury vapor is passed from vaporizer 36 through conduit means 37 to a passage 38 formed in the nozzle electrode 1-6 tangentially of pressure chamber 18. Mercury vapor entering chamber 13 tangentially flows vertically therein and, after being heated by the arc, discharges through the nozzle opening 12 into chamber 29. Such discharge into chamber 29 is primarily, as previously indicated, in the form of a plasma jet which is composed of neutral gas, ions and electrons, at high temperatures.

Referring next to FIGURES 3 and 4, the electromagnetic pump 35 is schematically illustratedas comprising a tube 39 having electrodes 41 mounted therein at diametrically opposite portions thereof. Tube 39 is formed of a suitable insulating material, so that electricity passing between the electrodes 41 is conducted not through the tube but through the liquid mercury therein. Magnet means, such as the illustrated

electrom agnets

42 and 43, are mounted on diametrically opposite sides of tube 39 in the same plane (perpendicular to tube 39) as electrodes 41 but rotated relative to a line between the electrodes.

The lines of magnetic force passing between the

electromagnets

42 and 43 are disposed at right angles tothe direction of current flow through the mercury between electrodes 41. It follows that when a suitable direct current source 44 is connected to electrodes M, and when the polarities of the electrodes and the poles of the magnets are properly related, a force will be present in tube 39 tending to force the mercury toward vaporizer 36 or to the left as viewed in FIGURES l and 3.

Suitable unshown auxiliary equipment, such as a check valve between pump 35 and vaporizer 36, may be provided in or adjacent the tube 39.

To summarize briefly the operation of the embodiment of FIGURES 1-4, the

electromagnets

42 and 43 are suitably energized from an unshown direct current source, and current source 44 (FIGURE 3) is applied to effect current flow through the liquid mercury in tube 39. Since such current flow is in a direction transverse to the lines of magnetic force between the

magnets

42 and 43, mercury is forced into the vaporizer 36 where it is vaporized. The resulting mercury vapor is conducted through conduit 37 and passage 38 (FIGURE 2) tangentially into pressure chamber 18, where it flows vortically and then passes out the nozzle opening 12 into chamber 29.

Current source 23 is then applied, and an arct is suitably initiated between the arcing elements lid and ill. The are passes through the canal in the vortically-flowing mercury vapor and is stabilized thereby. The mercury vapor and the electric arc combine to effect generation of the plasma jet which discharges at high velocity and temperature into the chamber 29. The plasma jet constitutes a source of light, such light being transmitted through the lens 13 to any desired region.

The mercury vapor thus introduced into chamber 29 is cooled by means of water flowing through the wall means 31. Such cooling action, and the action of the condenser 34, convert the mercury vapor back into liquid mercury which is then introduced into the electromagnetic pump 35 for recirculation as described.

Embodiment of FIGURE Referring next to FIGURE 5, the arcing elements are seen to comprise

coaxial metal electrodes

45 and 46. The electrodes are cylindrical in shape, and at least one, shown as number 45, is provided with an axial passage or opening 47 through which plasma may be discharged into a chamber or conduit 48. The chamber 48 may, if desired, be made to correspond to the chamber 29 shown in FIG- URE 1 in order that light emanating from the plasma discharged through passage 57 may be transmitted to a desired area.

A tubular insulating element 49 is mounted coaxially around both of the electrodes '45 and 45, the relationship being such that a cylindrical chamber 51 is formed coaxially of the passage 47. Chamber 51 is defined not only by the interior wall of insulator 49 but also by a suitable lens or other transparent window element 52. Element 52 has an inner wall which is coincident with the cylinder containing the inner wall of insulator 49, so that the vortical flow of gas in chamber 51 is not affected adversely.

A suitable current source 53 is connected to the

electrodes

45 and 46 through current conductors and also through suitable fiange portions 54 formed integral with the electrodes. Sealing means 55 are provided to prevent escape of gas from chamber 51 except through passage or opening 47.

The recirculation means illustrated in FIGURE 5 may be identical to that shown and described with relation to FIGURES 14. Thus, chamber 48 is connected to condenser 34 so that the mercury vapor will be condensed therein. The electromagnetic pump 35 is then employed to pump liquid mercury into the vaporizer 36, such liquid mercury then being vaporized and conducted toa passage 56 formed through insulator 49 tangentially of chamber 51. The cross-sectional area of passage 56 should be smaller than that of the passage 47 through which plasma is discharged into chamber 48.

To summarize the operation of the embodiment of FIGURE 5, the electromagnetic pump 35 is set in operation to efiect flow of mercury vapor through tangential passage 56 into annular chamber 51. Such vapor flows vortically and results in the presence of a canal axially of chamber 51 between the

electrodes

45 and 46. The current source 53 is then applied, and a suitable means (such as a momentary pulse of high voltage) is employed to initiate an electrical discharge or are between the

electrodes

45 and 46 through the canal defined by the whirling gas. Such arc or discharge is maintained continuously and is stabilized by the vortically-flowing mercury vapor. The gas and the arc combine to create plasma which flows through the opening 47 into chamber 48. The mercury vapor is then condensed in condenser 34, and the resulting liquid mercury is, pumped by pump 35-into the vaporizer 36.

Suitable cooling means, not shown may be provided both for the

electrodes

45 and 46, and for the wall of chamber 48.

The described forced recirculation means may also comprise any suitable pump device for pumping a suitable gas through the above-described recirculation circuit. Such pump device may pump various suitable gases (such as krypton, xenon or argon) in place of mercury vapor. The described current source is preferably a DC. source adapted to deliver a large current.

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. An electric plasma lamp, which comprises:

means to define a first gas chamber having an outlet opening therefrom,

first and second electrode means having arcing portions disposed in said first chamber, means to define a second gas chamber communicating with said opening on the opposite side thereof from said first chamber,

means to maintain a continuous electric are between said arcing portions in said first chamber,

means independent of said arc to effect forced recirculation of mercury vapor into said first chamber and thence through said opening into said second chamber and thence back into said first chamber,

said recirculation means including means to effect condensation of said mercury vapor to form liquid mercury, means to efiect flow of electric current through said liquid mercury in a predetermined direction, means to create a magnetic field extending through said liquid mercury in a direction at right angles to said predetermined direction, thereby creating a force effecting pumping of said liquid mercury, and means to vaporize said pumped liquid mercury and introduce the resulting mercury vapor into said first chamber, said recirculation means and said means to define said first chamber being so related to each other and to said electrodes that the gas flow in said first chamber is vortical about said are, and light-transmissive wall means to permit light generated as the result of said are to be transmitted away from the lamp.

2. A high-intensity light, which comprises:

wall means to define a gas-pressure chamber, at least a portion of said Wall means being formed of transparent material,

first and second electrode means having arcing portions disposed to maintain an electric arc in said chamber,

inlet means to introduce into said chamber a gas which is the vapor of a liquid,

outlet means to drain said gas continuously from said chamber,

means to maintain an electric arc in said chamber between said arcing portions to thereby generate light for transmission through said transparent material,

said arc heating said vapor,

condenser means to receive hot vapor from said outlet means and condense said hot vapor into a liquid,

evaporator means to vaporize said liquid into a vapor,

means to pump said liquid from said condenser means to said evaporator means, and

means to pass said vapor from said evaporator means to said inlet means.

3. Apparatus for generating high-intensity light, which comprises:

wall means to define an arc chamber,

at least a substantial portion of said wall means being formed of transparent material whereby to transmit light outwardly from said chamber, at least a major portion of the interior surface of said wall means being a surface of revolution about a central axis, first and second elongated electrodes having arcing end portions disposed in said are chamber at spaced points along said axis whereby to maintan an electric arc therealong, means to maintain continuously an electric are between said arcing portions, gas-inlet means to introduce gas continuously into said arc chamber, gas-outlet means to drain gas continuously from said chamber,

said gas-inlet and gas-outlet means each including passage means adjacent said chamber and directly communicating therewith,

said passage means of said gas-inlet and gasoutlet means being oriented to effect vortical flow of said gas in said chamber about said axis whereby to stabilize said arc along said axis in the canal through the verticallyflowing gas, said passage means of said gas-outlet means extending through one of said electrodes and being disposed adjacent said are, said passage means of said gas-inlet means being disposed to eifect flow of relatively cool incoming gas along said interior surface of revolution whereby gas must flow radially-inwardly before draining through said passage means of said gas-outlet means, and means to cool said gas and to effect recirculation thereof from said gas-outlet means to said gas-inlet means.

References Cited by the Examiner UNITED STATES PATENTS 3/1960 Giannini et al. 313-321 3,064,153 11/1962 Gage 31322 3,233,147 2/ 1966 Ducati 315111 JAMES W. LAWRENCE, Primary Examiner.

C. R. CAMPBELL, Assistant Examiner.

Claims

1. AN ELECTRIC PLASMA LAMP, WHICH COMPRISES: MEANS TO DEFINE A FIRST GAS CHAMBER HAVING AN OUTLET OPENING THEREFROM, FIRST AND SECOND ELECTRODE MEANS HAVING ARCING PORTIONS DISPOSED IN SAID FIRST CHAMBER, MEANS TO DEFINE A SECOND GAS CHAMBER COMMUNICATING WITH SAID OPENING ON THE OPPOSITE SIDE THEREOF FROM SAID FIRST CHAMBER, MEANS TO MAINTAIN A CONTINUOUS ELECTRIC ARE BETWEEN SAID ARCING PORTIONS IN SAID FIRST CHAMBER, MEANS INDEPENDENT OF SAID ARC TO EFFECT FORCED RECIRCULATION OF MERCURY VAPOR INTO SAID FIRST CHAMBER AND THENCE THROUGH SAID OPENING INTO SAID SECOND CHAMBER AND THENCE BACK INTO SAID FIRST CHAMBER, SAID RECIRCULATION MEANS INCLUDING MEANS TO EFFECT CONDENSATION OF SAID MERCURY VAPOR TO FORM LIQUID MERCURY, MEANS TO EFFECT FLOW OF ELECTRIC CURRENT THROUGH SAID LIQUID MERCURY IN A PREDETERMINED DIRECTION, MEANS TO CREATE A MAGNETIC FIELD EXTENDING THROUGH SAID LIQUID MERCURY IN A DIRECTION AT RIGHT ANGLES TO SAID PREDETERMINED DIRECTION, THEREBY CREATING A FORCE EFFECTING PUMPING OF SAID LIQUID MERCURY, AND MEANS TO VAPORIZE SAID PUMPED LIQUID MERCURY AND INTRODUCE THE RESULTING MERCURY VAPOR INTO SAID FIRST CHAMBER, SAID RECIRCULATION MEANS AND SAID MEANS TO DEFINE SAID FIRST CHAMBER BEING SO RELATED TO EACH OTHER AND TO SAID ELECTRODES THAT THE GAS FLOW IN SAID FIRST CHAMBER IS VORTICAL ABOUT SAID ARC, AND LIGHT-TRANSMISSIVE WALL MEANS TO PERMIT LIGHT GENERATED AS THE RESULT OF SAID ARC TO BE TRANSMITTED AWAY FROM THE LAMP.