US3612942A - Emitting assembly of an electronic bombardment gun - Google Patents

Emitting assembly of an electronic bombardment gun Download PDF

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US3612942A
US3612942A US880715A US3612942DA US3612942A US 3612942 A US3612942 A US 3612942A US 880715 A US880715 A US 880715A US 3612942D A US3612942D A US 3612942DA US 3612942 A US3612942 A US 3612942A
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emitting assembly
filament
washer
electrode
emitting
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US880715A
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Jean-Pierre Peyrot
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
    • H01J37/06—Electron sources; Electron guns
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
    • H01J37/06—Electron sources; Electron guns
    • H01J37/065—Construction of guns or parts thereof

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  • the present invention relates to an electronic welding gun and, more particularly, to a bombardment gun of the directheating type with an annular throttled cathode.
  • the invention has for its main object a filament which combines the advantages of direct heating guns and indirect heating guns.
  • the filament is of the type having coaxial conductors, which provides easy handling and accurate adjustment in position together with rapid assembly and dismantling;
  • the invention retains the advantages of direct heating, namely:
  • this filament can be readily changed at a distance by remote control, for example,
  • the invention is particularly directed to certain methods of application especially of electronic bombardment guns intended for welding, and also to certain methods of construction, and it is still more particularly directed, by way of new industrial products, to direct-heating electronic bombardment guns comprising the application of the same arrangements, their special elements, together with the electronic bombardment guns which comprise similar elements.
  • FIG. 1 is a view of a conventional filament of metal foil cutout and folded to shape
  • FIG. 2 is a view of a conventional filament of metal foil, cutout, shaped and punched;
  • FIG. 3 is a view of a conventional filament of coiled wire
  • FIG. 4 is a view of a conventional filament of wire wound in a spiral
  • FIG. 5 is a diagram of the mounting of a foil filament in a conventional direct-heating gun
  • FIG. 6 is a diagram of the mounting of a wire filament in a conventional direct-heating gun
  • FIG. 7 is a basic diagram of the mounting of a conventional indirect-heating filament and its emitting cathode
  • FIG. 8 is a perspective view of a coaxial filament according to the invention.
  • FIG. 9 is an exploded view of the coaxial filament shown in FIG. 8.
  • FIG. 10 is a half-sectional view of the coaxial filament of FIG. 8;
  • FIG. 11 is a view in cross section of the mounting of a coaxial filament of FIG. 10, in a gun of the PIERCE type;
  • FIG. 12 is a view in cross section of an alternative form.
  • FIG. 8 a metallic filament body 10 of tantalum, tungsten, tungsten/rhenium or other metal, of conical form and comprising at its lower portion an annular surface 11, having a thickness of 0.05 mm. for example and of slightly domed shape, pierced at its center with a hole of 0.4 mm. in diameter.
  • This cone is pierced on its periphery with a number of openings 14 permitting evacuation of air so as to obtain the vacuum necessary for the bombardment.
  • This dished portion gives a high degree of elasticity to the washer 23, which behaves like a flexible diaphragm and thus enables all thermal fatigue due to differences of expansion to be avoided.
  • the punched out form of the washer 23 permits the expansion of the central electrode 16 without adverse effect.
  • a weld is effected by electronic bombardment at 27 and in the direction of the arrow f2, in order to bind together intimately the parts 10 and 16.
  • the spacer 19 is placed on the flange 15 and its conical bearing surface 39 is centered in the cone I3 of the filament body 10.
  • the goffered metal washer 23 is placed on the spacer 19 and is centered in the dished portion 22 of this spacer. On other hand during this operation, the cylinder 17 of the central electrode 16 is centered with a close fit in the hole 26 of the washer 23.
  • a weld by electron bombardment will effected at 29 in the direction of fl so as to bind together the washer 23 and the central electrode 16 in an intimate manner.
  • the compact assembly thus formed is a coaxial filament for a direct-heating gun, for which it enables its own advantages already recited to be combined with those of conventional indirect-heating guns.
  • FIG. 11 illustrates very clearly the simplicity of the inputs of high-voltage current pole pieces 31 and 32, together with the simplicity of mounting or removal of the filament 10.
  • the metallic parts 31 and 32 insulated from each other by an insulating member 33, constitute the inputs of the high-voltage current.
  • a hole 34 to permit the passage of the filament.
  • a spotface or blind orifice 35 in which the filament comes to rest and is centered.
  • a threaded hole 36 in which is screwed a metal nut 37. By tightening this nut, the parts l0, l9 and 23 are compressed against each other.
  • a conical perforated filament having a flange at its widest portion and an emitting annular end portion pierced with an orifice at its narrowest portion
  • the emitting assembly as claimed in claim 1, comprising an electrode made of tantalum.
  • the emitting assembly as claimed in claim 1, comprising a electrode made of tungsten/rhenium.
  • the emitting assembly as claimed in claim 1, comprising a washer made of tantalum.
  • the emitting assembly as claimed in claim 1, comprising a washer made of tungsten/rhenium.

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  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Electron Sources, Ion Sources (AREA)
  • Particle Accelerators (AREA)
  • Microwave Tubes (AREA)
  • Solid Thermionic Cathode (AREA)

Abstract

An electronic bombardment gun comprising the emitting assembly of a goffered washer, an insulating spacer, a central electrode, a conical perforated filament, said filament being provided with a flange at its widest portion and with an emitting annular end portion pierced with an orifice at its narrowest part.

Description

United States Patent [72] Inventor Jean-Pierre Peyrot 8 domaine du Bel-Abord, Chilly-Mazarin, Essonne, France [21] Appl. No. 880,715 [22] Filed Nov. 28, 1969 [45] Patented Oct. 12, 1971 [32] Priority Nov. 29, 1968 [3 3] France [31 1 176,086
[54] EMITTING ASSEMBLY OF AN ELECTRONIC BOMBARDMENT GUN 13 Claims, 12 Drawing Figs.
[52] U.S.Cl 313/341, 3 1 3/23 8 [51] Int.Cl H01j 1/15 [50] Field of Search 313/237, 238, 341
[56] References Cited UNITED STATES PATENTS 1,980,447 11/1934 Stine 313/238 X Primary ExaminerDavid Schonberg Assistant Examiner-Paul A. Sacher Att0rneyKarl W, Flocks ABSTRACT: An electronic bombardment gun comprising the emitting assembly of a goffered washer, an insulating spacer, a central electrode, a conical perforated filament, said filament being provided with a flange at its widest portion and with an emitting annular end portion pierced with an orifice at its narrowest part.
EMITTING ASSEMBLY OF AN ELECTRONIC BOMBARDMENT GUN The present invention relates to an electronic welding gun and, more particularly, to a bombardment gun of the directheating type with an annular throttled cathode.
The invention has for its main object a filament which combines the advantages of direct heating guns and indirect heating guns.
It has also for its objects other arrangements which will be described more explicitly during the course of the description which follows, especially the following:
The filament is of the type having coaxial conductors, which provides easy handling and accurate adjustment in position together with rapid assembly and dismantling;
It is applicable to direct-heating guns of the PIERCE type, which are the simplest, the least bulky and the least expensive guns.
These guns, in which the heated filament serves as an emitting cathode, have a considerably defect; their filaments are fragile because they are made either from a very thin stamped sheet of metal or of very fine wire.
On the other hand, the setting in a good position -of the emitting portion is very difficult to carry out with respect to the cathode electrode, because of this fragility.
Another important defect which can be attributed to the deformation of this filament during heating and cooling which influences the accuracy of the emission image and the long life of the said filament.
On the other hand, indirect-heating guns, although of much more complicated construction, offer certain advantages:
No influence of the deformation of the heating filament;
Considerably rigidity of the emitting cathode;
Accurate emission image;
Possibility of a smaller emission face;
Very accurate positioning of the emissionface with respect to the cathode electrode.
By creating a rigid coaxial filament, the invention retains the advantages of direct heating, namely:
Simplicity of construction;
Small overall size;
Moderate production cost, with which are combined the advantages of indirect heating, namely:
No deformation of the filament;
Great rigidity of the emitting portion;
Accurate emission image;
Possibility of a very small emitting face;
Very accurate maintenance in a good position of the emitting surface with respect to the cathode electrode.
In addition, it offers other very valuable advantages which are not possessed by either of the types of gun referred to, namely:
rapid, easy and accurate positioning of the filament;
very great simplification of the filament supports through which the current supply is effected;
stability during heating due to the symmetrical arrangement,
reliability in construction, by virtue of the permissible tolerances,
guaranteed interchangeability,
very easy utilization of electronic bombardment in a protected cell, due to the fact that by virtue of its qualities, this filament can be readily changed at a distance by remote control, for example,
moderate production cost of the filament,
further substantial reduction in production cost with respect to the cheapest direct-heating guns.
The invention is particularly directed to certain methods of application especially of electronic bombardment guns intended for welding, and also to certain methods of construction, and it is still more particularly directed, by way of new industrial products, to direct-heating electronic bombardment guns comprising the application of the same arrangements, their special elements, together with the electronic bombardment guns which comprise similar elements.
Other characteristic features and advantages will be brought out from the description which follows below, reference being made to the accompanying drawings which show, purely by way of indication and not in any limitative sense, two forms of embodiment of the invention.
In these drawings:
FIG. 1 is a view of a conventional filament of metal foil cutout and folded to shape;
FIG. 2 is a view of a conventional filament of metal foil, cutout, shaped and punched;
FIG. 3 is a view of a conventional filament of coiled wire;
FIG. 4 is a view of a conventional filament of wire wound in a spiral;
FIG. 5 is a diagram of the mounting of a foil filament in a conventional direct-heating gun;
FIG. 6 is a diagram of the mounting of a wire filament in a conventional direct-heating gun;
FIG. 7 is a basic diagram of the mounting of a conventional indirect-heating filament and its emitting cathode;
FIG. 8 is a perspective view of a coaxial filament according to the invention;
FIG. 9 is an exploded view of the coaxial filament shown in FIG. 8;
FIG. 10 is a half-sectional view of the coaxial filament of FIG. 8;
FIG. 11 is a view in cross section of the mounting of a coaxial filament of FIG. 10, in a gun of the PIERCE type;
FIG. 12 is a view in cross section of an alternative form.
There is shown in FIG. 8 a metallic filament body 10 of tantalum, tungsten, tungsten/rhenium or other metal, of conical form and comprising at its lower portion an annular surface 11, having a thickness of 0.05 mm. for example and of slightly domed shape, pierced at its center with a hole of 0.4 mm. in diameter. This circular surface 11 is inscribed in a cylinder I2 having a height f=l.5 mm. and a thickness c=0.3 mm. This cylinder is continued at its upper portion by a cone 13 having a height h=6.5 mm. a thickness c=0.3 mm. and a large diameter d=4.8 mm. This cone is pierced on its periphery with a number of openings 14 permitting evacuation of air so as to obtain the vacuum necessary for the bombardment. This cone terminates at its upper portion in a flange 15 having an external diameter d=8 mmxand a thickness e=0.3 mm.
A central metal electrode 16, for example of tantalum, tungsten, tungsten/rhenium or other metal has the shape of a cylinder 17 having a diameter 8=l mm. and a height of h'=7 mm., terminating at its lower portion in a smaller cylinder 18 giving a diameter D -0.4 mm. and a height A=2 mm.
An insulating spacing disc 19, of alumina for example, of cylindrical shape, having an external diameter d=8 mm. and a thickness e=l mm., a comprises at its lower portion a conical boss 20 which during assembly is centered in the upper portion of the cone 13. In the central part of this boss is pierced a hole 21 having a diameter D. The upper portion of the spacer is formed into a conical dished portion 22.
A metal washer 23 of tantalum, tungsten, tungsten/rhenium or other metal, having an external diameter d=8 mm. and a thickness e=0f3 mm. is provided at its center with a stamped dished portion 24 which is centered during the assembly in the dished portion 22 of the spacer 19. This dished portion gives a high degree of elasticity to the washer 23, which behaves like a flexible diaphragm and thus enables all thermal fatigue due to differences of expansion to be avoided. In other words, the punched out form of the washer 23 permits the expansion of the central electrode 16 without adverse effect.
In the hole 40 of diameter 0.4 in the circular surface 11 of the filament 10, the cylinder 18 of the central electrode 16 mounted with a close fit.
A weld is effected by electronic bombardment at 27 and in the direction of the arrow f2, in order to bind together intimately the parts 10 and 16.
The spacer 19 is placed on the flange 15 and its conical bearing surface 39 is centered in the cone I3 of the filament body 10.
The goffered metal washer 23 is placed on the spacer 19 and is centered in the dished portion 22 of this spacer. On other hand during this operation, the cylinder 17 of the central electrode 16 is centered with a close fit in the hole 26 of the washer 23.
A weld by electron bombardment will effected at 29 in the direction of fl so as to bind together the washer 23 and the central electrode 16 in an intimate manner.
The compact assembly thus formed is a coaxial filament for a direct-heating gun, for which it enables its own advantages already recited to be combined with those of conventional indirect-heating guns.
The basic diagram of FIG. 11 illustrates very clearly the simplicity of the inputs of high-voltage current pole pieces 31 and 32, together with the simplicity of mounting or removal of the filament 10. The metallic parts 31 and 32, insulated from each other by an insulating member 33, constitute the inputs of the high-voltage current. In the part 31 has been bored a hole 34 to permit the passage of the filament. in the parts 31 and 33 has been machined a spotface or blind orifice 35, in which the filament comes to rest and is centered. in the part 32 is provided a threaded hole 36 in which is screwed a metal nut 37. By tightening this nut, the parts l0, l9 and 23 are compressed against each other.
The pressure and the contact of the nut 37 against the part 23 and in the threaded portion 36 of the part 32, permits an excellent transmission of the high-voltage current from the part 32 to the parts 23 and 16.
The pressure of the nut on 31 and 10, and the contact of these parts with each other, permits the transmission of the highvoltage current between the parts 31 and 10.
The passage of the current coming from the parts 23 and 16 into the coaxial annular emitting ring 11 of the part 10, while passing through the circular surface having a section very much less than that of the parts 10, 16 and 23, causes it to heat-up. This part of the filament is brought up to high temperature and becomes emitting under the common conventional conditions of welding by electron bombardment. In particular, there can be sewn in FIG. 12 an alternative form in which, for reasons of bulk, in the case of welding in places difficult of access, the filament is flatter and the current supply inputs are made in different ways and are embedded in the insulated trolley 30 mounted on rollers 28. The parts to be welded, 9 and 9, are placed in the immediate vicinity of ring 11.
There has thus been constructed according to the invention, a compact cylindrical assembly having the smallest possible dimensions.
It will of course be understood that the present invention has been described above purely by way of indication and not in any [imitative sense and that any modification of detail may be made thereto, in conformity with its spirit, without thereby departing from its scope.
What I claim is:
l. The emitting assembly of an electronic bombardment gun comprising:
a conical perforated filament having a flange at its widest portion and an emitting annular end portion pierced with an orifice at its narrowest portion,
a central electrode centered in said filament,
an insulating spacer centered at the widest portion of said filament,
and a goffered washer centered in relation to said insulating spacer.
2. The emitting assembly as claimed in claim 1, in which said spacer is provided with a dished portion of a first conical bearing surface which is mated to the interior of said flange against the widest portion of the cone of the filament body.
3. The emitting assembly as claimed in claim 1, in which the goffering of said washer comprises a conical seating which is applied against a second conical bearing surface provided on a face of said spacer opposite to said first'conical bearing surface.
4. The emitting assembly as claimed in claim 1, in which said insulating spacer is of refractory material and is pierced with a central orifice through which the electrode slides freely.
5. The emitting assembly as claimed in claim 1, in which the electrode is a forced fit into and is welded to one extremity of the bottom of the filament and its other extremity is fitted and welded to the interior of the goffering of said washer.
6. The emitting assembly as claimed in claim 5, in which the electrode is composed of a portion of large diameter and a portion of small diameter.
7. The emitting assembly as claimed in claim 1, comprising an electrode made of tantalum.
8. The emitting assembly as claimed in claim 1, comprising a electrode made of tungsten/rhenium.
9. The emitting assembly as claimed in claim 1, comprising a washer made of tantalum.
10. The emitting assembly as claimed in claim 1, comprising a washer made of tungsten/rhenium.
11. The emitting assembly as claimed in claim 1, further comprising a first pole-piece pierced with an internally threaded hole having a diameter greater than the external diameter of said washer; a second pole-piece pierced with an orifice having a diameter greater than the means diameter of said conical filament, an insulating member pierced with an orifice corresponding to the common diameter of said washer and of said flange, a spotface provided in said insulating member and in said second pole-piece permitting the clamping of the washer and the spacer against the flange by means of a nut screwed into said internal threaded portion.
12. The emitting assembly as claimed in claim 11, in which the pole-pieces are connected to a source of high-frequency current.
13. The emitting assembly as claimed in claim 12, in which said pole pieces are connected on an insulating trolley, said filament being given an extra-flat form so as not to project from the external surface of the trolley in the direction of parts to be welded.

Claims (13)

1. The emitting assembly of an electronic bombardment gun comprising: a conical perforated filament having a flange at its widest portion and an emitting annular end portion pierced with an orifice at its narrowest portion, a central electrode centered in said filament, an insulating spacer centered at the widest portion of said filament, and a goffered washer centered in relation to said insulating spacer.
2. The emitting assembly as claimed in claim 1, in wHich said spacer is provided with a dished portion of a first conical bearing surface which is mated to the interior of said flange against the widest portion of the cone of the filament body.
3. The emitting assembly as claimed in claim 1, in which the goffering of said washer comprises a conical seating which is applied against a second conical bearing surface provided on a face of said spacer opposite to said first conical bearing surface.
4. The emitting assembly as claimed in claim 1, in which said insulating spacer is of refractory material and is pierced with a central orifice through which the electrode slides freely.
5. The emitting assembly as claimed in claim 1, in which the electrode is a forced fit into and is welded to one extremity of the bottom of the filament and its other extremity is fitted and welded to the interior of the goffering of said washer.
6. The emitting assembly as claimed in claim 5, in which the electrode is composed of a portion of large diameter and a portion of small diameter.
7. The emitting assembly as claimed in claim 1, comprising an electrode made of tantalum.
8. The emitting assembly as claimed in claim 1, comprising a electrode made of tungsten/rhenium.
9. The emitting assembly as claimed in claim 1, comprising a washer made of tantalum.
10. The emitting assembly as claimed in claim 1, comprising a washer made of tungsten/rhenium.
11. The emitting assembly as claimed in claim 1, further comprising a first pole-piece pierced with an internally threaded hole having a diameter greater than the external diameter of said washer; a second pole-piece pierced with an orifice having a diameter greater than the means diameter of said conical filament, an insulating member pierced with an orifice corresponding to the common diameter of said washer and of said flange, a spotface provided in said insulating member and in said second pole-piece permitting the clamping of the washer and the spacer against the flange by means of a nut screwed into said internal threaded portion.
12. The emitting assembly as claimed in claim 11, in which the pole-pieces are connected to a source of high-frequency current.
13. The emitting assembly as claimed in claim 12, in which said pole pieces are connected on an insulating trolley, said filament being given an extra-flat form so as not to project from the external surface of the trolley in the direction of parts to be welded.
US880715A 1968-11-29 1969-11-28 Emitting assembly of an electronic bombardment gun Expired - Lifetime US3612942A (en)

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JP (1) JPS4912824B1 (en)
CH (1) CH510484A (en)
DE (1) DE1959950A1 (en)
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GB (1) GB1256379A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4598226A (en) * 1984-12-17 1986-07-01 Clegg John E Concave conical foil-filament lamp
WO1999016101A2 (en) * 1997-09-24 1999-04-01 The Welding Institute Charged particle beam emitting assembly

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2214705A (en) * 1988-01-26 1989-09-06 English Electric Valve Co Ltd Directly heated cathode

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1980447A (en) * 1931-04-14 1934-11-13 Lincoln Electric Co Arc welding apparatus

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1980447A (en) * 1931-04-14 1934-11-13 Lincoln Electric Co Arc welding apparatus

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4598226A (en) * 1984-12-17 1986-07-01 Clegg John E Concave conical foil-filament lamp
WO1999016101A2 (en) * 1997-09-24 1999-04-01 The Welding Institute Charged particle beam emitting assembly
WO1999016101A3 (en) * 1997-09-24 1999-06-17 Welding Inst Charged particle beam emitting assembly
US6404115B1 (en) 1997-09-24 2002-06-11 The Welding Institute Particle beam emitting assembly
EP1587129A1 (en) * 1997-09-24 2005-10-19 The Welding Institute Improvements relating to charged particle beams

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DE1959950A1 (en) 1970-06-25
GB1256379A (en) 1971-12-08
JPS4912824B1 (en) 1974-03-27
FR1599106A (en) 1970-07-15
CH510484A (en) 1971-07-31

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