US3894209A

US3894209A - Nozzle for energy beam system

Info

Publication number: US3894209A
Application number: US418721A
Authority: US
Inventors: Thomas E Fairbairn
Original assignee: Sirius Corp
Current assignee: Sirius Corp
Priority date: 1973-11-23
Filing date: 1973-11-23
Publication date: 1975-07-08
Anticipated expiration: 1992-07-08
Also published as: GB1484156A; CA1039051A; JPS50105731A; DE2456042A1; BE822528A; AU7567574A

Abstract

An improved nozzle for an energy beam system including an outer hollow cylindrical sleeve having an internal radial plate across the interior of the sleeve with the plate having axial passages therethrough, an inner hollow tubular sleeve telescopically mounted in one end of the outer sleeve, and an elongated hollow electrode telescopically mounted interiorly of both sleeves and radially spaced apart from the inner sleeve.

Description

United States Patent 1191 Fairbairn July 8, 1975 [5 NOZZLE FOR ENERGY BEAM SYSTEM 3,307,011 2/1967 Baird 219/75 X 3,514,567 5/1970 Strang 1 219/75 [75] Inventor- 312 Fa'rbalm Wesfland, 3,648,015 3/1972 Fairbaim 219/121 P [73] Assignee: Sirius Corporation, Toledo, Ohio Primary Truhe Assistant ExaminerG. R Peterson [22] 1973 Attorney, Agent, or FirmCullen, Settle, Sloman & 21 Appl. No.: 418,721 Cantor [52] U.S. Cl. 219/121 P [57]. ABSTRACT 51 1111. C1 B73k 9/00 nozzle an energy beam System [58] Field of Search 219mm P 74 75 eluding an outer hollow cylindrical sleeve having an 3 2 internal radial plate across the interior of the sleeve with the plate having axial passages therethrough, an [56] References Cited inner hollow tubular sleeve telescopically mounted in one end of the outer sleeve, and an elongated hollow UNITED STATES PATENTS electrode telescopically mounted interiorly of both {3 i sleeves and radially spaced apart from the inner aw 1 3,130,292 4/1964 Gage et al. 219/121 P x S 3,221,212 11/1965 Gorowitz et a1 219/121 P 7 Claims, 4 Drawing Figures POWDER SUPPLY GAS 20 BACKGROUND or THE-INVENTION This invention relatesto an improved nozzle for an energy beam system such as the system disclosed in my U.S. Pat. No. 3,648,015, issued Mar. 7, 1972. In my prior U.S. Pat. No. 3,648,015, there is described a system for generating a narrow radio frequency electronic beam outwardly from a nozzle with the ability to utilize this beam (among other purposes) for spraying a powder or aggregate as a coating upon a target.

Whilethe system including the nozzle described in my prior patent operates successfully, I have found that better results including better control of the beam may be obtained by the improved nozzle of the present invention.

SUMMARY OF THE INVENTION The present invention provides an improved nozzle for'an energy beam system, the improved nozzle including an outer sleeve, an inner sleeve, and a hollow electrode secured within the inner sleeve. Both the hollow electrode and the inner sleeve are independently telescopically adjustable relative to the outer sleeve.

The energy system itself includes a radio frequency generator having, as its output tank coil, a first hollow coiled metal tube, with a second hollow metal tube inside the first metal tube. A mechanical" input is supplied to a high current low voltage point of the tubes in theform of a gas (as hereinafter explained); gas is separately supplied to each tube. The output of each tube is taken at the low current high voltage point and is coupled to the nozzle; the outer tube couples gas around the electrode (interiorly of the inner sleeve) and the inner tube couples gas to the hollow center of the electrode.

A radial plate within the outer sleeve has a plurality of apertures therethrough; a central aperture provides for the application of the inner tube gas through the hollow electrode and the outer apertures provide for the application of the outer tube gas within the inner sleeve but exteriorly of the electrode.

The improved nozzle of the present invention provides for a laminar flow of the gases; the gas around the electrode appears as an outer tube or column sheathing the energy beam, and the gas through the electrode appears as an inner tube or column and conducts the en- 7 ergy beam to the target. Each column of gas, in longitudinal cross-section, appears as laminar flow. The relative telescopic adjustments of the electrode and the inner sleeve relative to the outer sleeve provides for focusing of the energy beam, and for greater intensity of the energy beam with reduced scattering.

BRIEF DESCRIPTION OF THE DRAWINGS The various objects and advantages of the present invention will become more apparent upon reading the following detailed description of the invention taken in conjunction with the drawings.

In the drawings, wherein like reference numerals identify corresponding parts:

FIG. 1 is a schematic illustration of the beam system;

FIG. 2 is a sectional view of the improved nozzle of the present invention as seen in the plane of arrows 2-2 of FIG. 4, connected schematically to the energy system;

2 FIG. 3 is a perspective illustration of the nozzle of FIG. 2; and,

FIG. 4 is an end view of the nozzle as seen in the plane of the arrows 4-4 of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION The improved nozzle of the present invention is explained in the context of an energy beam system such as that described in my U.S. Pat. No. 3,648,015. The aforementioned Patent contains a description of the energy beam system and the principles and theories of operation, together with various advantages and usages of such a system. Therefore, the description in U.S. Pat. No. 3,648,015 is hereby incorporated by reference and only certain features of the prior patent will be repeated here in detail, it being understood that the nozzle 10 of the present invention is an improvement over the nozzle 18 of the prior patent.

The improved nozzle 10 of the present invention is adapted to be connected to a maximum voltage zero current point ofa tank coil 12 of a radio frequency generator 14. The tank coil may be made from hollow copper tubing and includes an internal metal tube 16 extending through the coils of the outer tube 12.

A feed or supply line couples gas under pressure to both the inner and outer tubes of the tank coil with the gas being introduced at a maximum current zero voltage point of the

tubes

12 and 16. Specifically. gas may be provided from two gas supplies l8 and 20 through

appropriate T fittings

21 and 22 to the coil or

tubes

12 and 16 respectively. One or more powders or aggregates 24, may be coupled through each T fitting for introduction into the

respective tubes

12 and 16 by op ning one inlet to each T fitting as desired.

In the operation of the nozzle according to the principles of the present invention the gas utilized in each tube may be air, an inert gas or combination of inert gases or even liquids or gases containing some solid particles. The specific parameters for the gas will be set forth in greater detail hereinafter. However, for the purpose of explanation of the present invention the word gas will be used generically to include air, inert gases, and liquids whether or not they include solid particles.

Upon making the appropriate electrical connections and turning on the gas as set forth in my prior patent, a beam emanates from the nozzle 10 and is directed at a target 28.

The'details of the nozzle will now be explained. The nozzle includes an outer hollow cylinder or sleeve 30 having a first end 32 which may be defined as the nozzle orifice or opening and a second end 34 which is ultimately coupled to the supply of gas. The hollow sleeve 30 includes an internal radial plate 36 having a central aperture 38 and a plurality of peripheral apertures 40. The front or forward portion of the central aperture 38 is threaded as at 42.

Telescopically mounted interiorly of the outer sleeve 30 is a second hollow cylindrical sleeve 50 having a first end 52 exteriorly of the sleeve 30 and a second end interiorly of the sleeve. The sleeve 50 has a radially outwardly extending plug or stud 54 threaded therein, which extends outwardly through a suitable axially elongated slot 56 in the wall of the sleeve 30. Movement of the plug or stud '54 relative to the slot 56 serves to telescopically position the sleeve 50 within the sleeve 30.

The nozzle of the present invention includes a hollow electrode 60 having a first end or tip 62 and an elongated central hole 64. The rear of the electrode 60 is threaded as at 66 into the threads 42 in the central aperture 38 of the plate 36; The electrode is radially spaced apart from the inner sleeve 50, as at 68.

The electrode is further adjustably mounted relative to the nozzle through a plurality of threaded holes 70 in the periphery of the sleeve 30 which extend radially inwardly. Fasteners such as set screws 72 threaded in the holes 70 serve to frictionally engage and retain the electrode 60. Three set screws, each 120 apart are preferred. The set screws are metallic and conduct the radio frequency energy from the tank coil 12 and outer sleeve 30 to the electrode 60.

When the nozzle is connected to the energy system of the present invention, the inner tube 16 and its associated gas 20 are connected through'the central aperture 38 in the radial plate through the hollow portion or hole, 64 in the electrode 60. The outer tank coil or tubel2 and its associated gas'l8 is connected to-the second end-34 of the outer sleeve so that the gas 18 may becoupled'through the peripheral apertures 40 and'along the exterior of the electrode 60 but interiorly of the inner sleeve 50. v

With appropriate adjustments in the gas pressures, it has been determined that the desired phenomenon of laminar or columnar gas flow is obtained under several concurrent conditions. Specifically, the outer" gas, i.e., the gas through the peripheral apertures 40 and along the outside of the electrode 60 should be under a pressure or flow rate or standard cubic feet per hour (SCFH). The interior gas, through the central aperture and through the interior of the electrode should be under a velocity of 175 standard cubic feet per hour (SCFH). Another condition is that the tip 62 of the electrode'should be in the same radial plane as the first end 52 of the sleeve 50. Under these conditions, laminar or columnar flow is obtained. Specifically, this laminar or columnar flow results in an energy beam emanating from the hole in the tip of the electrode and being conducted by the inner gas to the target 28.

- The gas coming through the nozzle around the exterior of the electrode 60 sheathes, surrounds or focusses the energy beam. From'the electrode tip 62 to the, target the gas through the center of the electrode remains independent of the gas surrounding the electrode. Hence the flow of the gas is referred to as laminar or columnar. Each gas maintains its straight or laminar flow (in cross-section) or, since each orifice or opening is circular, the gases are actually in tubes or hollow columns from-the orifice of the nozzle to the target.

The outer sleeve 30 and inner sleeve 50 may both be manufactured of copper or brass. Alternately, the inner sleeve may be a ceramic such as boron nitride 215 sold under the'name Combat by the Carborundum Com- 7 pany. Optionally, it has been found that both the outer sleeve and inner sleeve may be manufactured of stainless steel.

The electrode may be of tungsten or stainless steel or preferably of molybdenum.

With the powder supply turned off through the respective T fittings or valves, the energy beam maybe utilized for welding, cutting, melting or drilling, etc. Once the powders through either or both of the gases are turned on, the powder or aggregate material may be deposited on to the target and coated or.fused into place. Certain additional features are provided by the nozzle drthe present inventioii when the powder is introduced, Specifically,,9neimportant feature is that the gas rate of flow is not changed by the introduction of powder. Thati's, the rates of flow are maintained constantand not perturbed .or obstructed by the introduction of powder. Thus, the introduction of the powder does not adversely affect thelaminarflow'. The main reason isthere are no perturbations of the R.F. energy, with respect to incident and reflected power, when the powder is fed into the beam from the center electrode hole. That is, the power does not change.

For bestoperation of the apparatus using the nozzle of the present invention, the front face or end 32 of sleeve 30, the front end 52 of sleeve and the tip 62 of the electrode 60. must all be parallel and radial with respect to the elongated axis of the nozzle. Furthermore, the tip 62 of the electrode and the front end 52 of the sleeve 50 must be in the same radial plane. If his latter condition is not maintained, the intensity and focus of the energy beam is changed from a sharp focus at the target to a beam which is focused either short of the target or which is a scattered beam as it hits the tar-. get (corresponding to a beam which would focus be.- yond the target). Furthermore, this lack ofaccurate focus upon the target may cause a slight sputteringof the electrode tip 62. g I

Thus,.for best results, the parallel faces of the two sleeves and the electrode and the alignment of the inner sleeveand the electrode should be.maintained. To aid in focussing the beam the inner sleeve is telescopically adjustable, by moving the adjusting stud 54. The electrode is adjustable telescopically, by the threads 66 and threads 42 in the outer sleeve and by the set screws. The set screws also serve to center the electrode within the interior of sleeve 50 to maintain the space 68 for the outer sheath gas.

The foregoing is a description of the preferred embodiment of the present invention and should not be read in a limiting sense but only as describing the underlying concepts of the present invention. The invention may be developed further within the scope of the following claims.

I claim:

'1. In an apparatus for generating an energy beam, said apparatus including a sine wave generator having a tank coil formed of a first hollow electrically conductive tube and a second hollow electrically conductive tube positioned interiorly of said first hollow tube, and

a system for supplying gas through each of said tubes,

the improvement of a nozzle adapted to be attached at one: end of said tubes comprising:

- a first hollow cylindrical sleeve 'having first and second ends and an integral interiorradial plate intermediate said first and second ends, said plate having at least two axial passages therethrough;

a second hollow cylindrical sleeve;

a hollow electrode;

means for mounting said hollow electrode radially interiorly of said first sleeve and in communication with said first axial passagefordefining a first con- .tinuous flow path through said nozzle from said second tube, through a first .axial passage in said plate and through said electrode; and

means for mounting said second sleeve radially inter- ,rnediate said electrode and said first sleeve and in communication with saidsecorid axial passage for sleeve and said electrode each extend axially outwardly defining a second continuous flow path through said no'zzle from said first tube, through said second axial passage in said plate. and through said second sleeve radially exteriorly of said electrode;

whereby, upon the application of gas through each of 5 said tubes, a laminar gas flow is produced by said nozzle including an inner column of gas emanating from said hollow electrode and conducting said energy beam and an outer column of gas emanating between said electrode and said second sleeve and surrounding and sheathing said energy beam.

2. The nozzle as in claim 1 wherein said hollow electrode is axially and radially adjustably mounted interiorly of said sleeves.

3. The nozzle as in claim 1 wherein one end of said electrode is threadably mounted within said radial plate.

4. The nozzle as in claim 1 wherein said first sleeve includes an axially elongated slot extending radially therethrough, and said second sleeve includes means extending radially outward therefrom and extending through said slot for telescopically adjusting said second sleeve interiorly of said first sleeve.

5; The nozzle as in claim 1 wherein said second from said first sleeve and terminate in the same place transversely of their axial dimension. 6.,An improved nozzle comprising: an outer hollow cylindrical sleeve having first and second ends and an integral internal radial plate intermediate said ends, said plate having an axial passage therethrough; an elongated hollow electrode; means for mounting said electrode radially interiorly of said first end of said outer sleeve, said hollow electrode being in communication with said axial passage for defining a first continuous flow path from said second outer sleeve end, through said radial plate passage and through said hollow electrode; an'inner hollow tubular sleeve; and means for mounting said inner sleeve radially interiorly of said outer sleeve and radially exteriorly of said electrode, said inner sleeve for defining a second continuous flow path through said inner sleeve, said second flow path being radially outwardly of said first flow path. 7. The nozzle of claim 6 wherein said inner sleeve and said electrode are telescopically mounted.

Claims

1. In an apparatus for generating an energy beam, said apparatus including a sine wave generator having a tank coil formed of a first hollow electrically conductive tube and a second hollow electrically conductive tube positioned interiorly of said first hollow tube, and a system for supplying gas through each of said tubes, the improvement of a nozzle adapted to be attached at one end of said tubes comprising: a first hollow cylindrical sleeve having first and second ends and an integral interior radial plate intermediate said first and second ends, said plate having at least two axial passages therethrough; a second hollow cylindrical sleeve; a hollow electrode; means for mounting said hollow electrode radially interiorly of said first sleeve and in communication with said first axial passage for defining a first continuous flow path through said nozzle from said second tube, through a first axial passage in said plate and through said electrode; and means for mounting said second sleeve radially intermediate said electrode and said first sleeve and in communication with said second axial passage for defining a second continuous flow path through said nozzle from said first tube, through said second axial passage in said plate, and through said second sleeve radially exteriorly of said electrode; whereby, upon the application of gas through each of said tubes, a laminar gas flow is produced by said nozzle including an inner column of gas emanating from said hollow electrode and conducting said energy beam and an outer column of gas emanating between said electrode and said second sleeve and surrounding and sheathing said energy beam.

5. The nozzle as in claim 1 wherein said second sleeve and said electrode each extend axially outwardly from said first sleeve and terminate in the same place transversely of their axial dimension.

6. An improved nozzle comprising: an outer hollow cylindrical sleeve having first and second ends and an integral internal radial plate intermediate said ends, said plate having an axial passage therethrough; an elongated hollow electrode; means for mounting said electrode radially interiorly of said first end of said outer sleeve, said hollow electrode being in communication with said axial passage for defining a first continuous flow path from said second outer sleeve end, through said radial plate passage and through said hollow electrode; an inner hollow tubular sleeve; and means for mounting said inner sleeve radially interiorly of said outer sleeve and radially exteriorly of said electrode, said inner sleeve for defining a second continuous flow path through said inner sleeve, said second flow path being radially outwardly of said first flow path.

7. The nozzle of claim 6 wherein said inner sleeve and said electrode are telescopically mounted.