US2365855A

US2365855A - X-ray tube

Info

Publication number: US2365855A
Application number: US468066A
Authority: US
Inventors: Zed J Atlee
Original assignee: General Electric X Ray Corp
Current assignee: General Electric X Ray Corp
Priority date: 1942-12-07
Filing date: 1942-12-07
Publication date: 1944-12-26
Anticipated expiration: 1961-12-26
Also published as: FR940475A; GB573587A; BE474128A

Description

Dec. 26, 1944. Z, J, ATLEE 2,365,855

X-RAY TUBE Filed Dec. 7, 1942A I N VEN TOR.

Patented Dec. 26, `1944 Electric X-Ray Corporation, Chicago, Ill., a corporation of New York Application December 7, 1942, serial No. 468,066

` (ci. 25o-144) 8 Claims.

'I'he present invention relates in general to electronics and has more particular reference to an improved high frequency electronic tube, the invention relating especially to an X-ray generator.

An important object of the invention is to provide an electronic tube including an anode, a

cathode, and a sealed envelope enclosing the same, having enclosed within the envelope transformer means for supplying relatively high oper-` ating voltage between the anode and cathode, including facilities for energizing the transformer means from a relatively low voltage energy source outwardly of the envelope.

Another object ofthe invention is to provide an electronic tube including an anode, a cathode. and a sealed envelope enclosing the same, having enclosed'wthin the envelope oscillator means for supplying operating energy at relatively high frequency between the anode and cathode, including facilities for energizing the oscillator means from a low frequency powersource out` wardlyof the envelope.

Another important object is vto provide an electronic tube having transformer and associated oscillator means contained within the envelope of the tube, together with an anode and cooper-` ating cathode whereby all of the high voltage and high frequency elements required to operate the electronic device are contained within the sealed envelope of the tube, only relatively low volt` age normalfrequency equipment being required outwardly of the tube for the operation of the same.

`Still another important Aobject isto provide an electronic Atube having means forming an oscillator'built into` the anodeV structureof the tube;

A further importantv object is to provide an electronic tube having transformer means en closed within the tube envelope wherein a winding of. the transformer `means is utilized as a support for the anode of the tube. i

Another object is to provide an electronic tube having a main anode and cathode enclosed in an envelope. together with anoscillatorincluding a cathode wherein the main cathode 'and the oscillator cathode comprise filaments energized from a power source outwardly of the envelope through a common conductor extending through a seal formedin a wallof the envelope. Y

The foregoing and numerous otherl important objects, advantages, and inherent l functions l of the invention will be `fully understood from the following'descriptiomwhich, taken in connection with the accompanying drawing, discloses a pref -ferred embodiment of the invention.

Referring to the drawing:

Figure 1 is a diagrammaticillustration of an electronic device embodying the present inven. tion;

. Figure 2 is a sectional View taken through a preferred form of device embodying the invention; and

Figures 3 and 4 are sectional views taken substantially and respectively along the lines 3-3 and 4-4 in Figure 2.

'I o illustrate the invention the drawing shows an electronic device comprising an X-ray generator having an anodel I3 forming a target surface I5, and a cathode comprising a head and an electron emitting filament I9, the anode and cathode being enclosed and supported within a sealed envelope 2| formed with an X-ray emitting window 23 opposite the target surface of the anode. Also enclosed and supported within the sealed envelope 2| is a transformer 25 and an oscillator 3|, the transformer 25 comprising a primary low voltage Winding 2l and a secondary high voltage winding 29. The oscillator comprises a cathode 33 whichfmay be formed as a filament, an anode or plate 35 and a. grid 3l disposed between the cathode and the plate for the purpose of controlling electron flow therebetween.

The several elements are interconnected within the y envelope, and conductors extending through seals 39 in the envelope walls are provided -for electrically connecting the interconnected elements within the envelope with a suitablevpower source outwardly of the envelope. To this endthe plate 35 of the oscillator maybe electrically connected, as by conductor means 4|, with the interconnected ends of the transformer windings 2l and 29, the low voltage winding 21 being also connected with a conductor 43 which extends outwardly of the envelope through a seal 39. The high voltage winding 29 of the transformer is electrically connected with the anode I3, as by conductor means 45. The grid 31 of the oscillator is connected to a conductor 4l which extends outwardly of the envelope through a seal 39, and the filaments |9 and 33 are connected in common to conductor means 49 and are individually connected, respectively, to separate conductors 5| and 53. Each of the conductors 49, 5| and 53 extend outwardly of the envelope through .suitable seals 39.

Any suitable means may, of course, be employed for supporting the elements .within the envelope 2|, although, as .shown more particularly in Figure 2, the elements are preferably all supported on a single mounting 55 which forms a sealed closure at one end of the envelope and through which the

conductors

41, 49,

mote from the seal 59, being sealingly secured to the support member 55, which preferably comprises a metal plate sealingly brazed to the short sleeve 6I. The envelope 2I, including the reentrant portion 51, the sleeve 6I and the plate 55 thus form a sealed enclosure,4 and the plate 55 forms a support on which the elements of the device are carried. The plate 55 is formed with a plurality of openings 63 therethrough, in which the

conductors

41, 49, 5I and 53 are sealingly mounted and preferably insulated from the metal plate 55 by glass' globules extending in the openings 63 and forming the conductor seals 39. Within the envelope the mounting 55 preferably carries a cylindrical frame 65 enclosing a space 61 adjacent the inner face of the plate 55. Within the frame 65 the oscillator grid 31 is arranged preferably in the form of a helical coil which is supported on and electrically connected at one end to the conductor 43 which extends through and is supported on the plate 55. Within the helical coil 31 extends a support frame 69, preferably comprising legs of electrical conducting material, the lower ends of which are mounted on insulated supports carried by the plate 55, at least one of which supports extends through the plate to form a part of the conducting means 49. The support frame 69 extends outwardly of the frame S5 within the envelope 2l and carries the cathode I1 in which is mounted the filament I9. One end of the lament I9 is preferably electrically connected to the head I1, and hence through the frame 99 is electrically connected with the conductor 49. The other end of the lament I9, is electricallyv connected with the conductor means 53 whichis insulated from the head I1, as by means of insulating blocks 1I, and the conductor 53 extends from the filament within the frame 69 and thence outwardly of the envelope through a seal 39. The oscillator filament 33 preferably comprisesa helical coil disposed within the space 61 in position enthe frame 65 which is of metal and which forms the plate or anode of the oscillator 3|. The plate remote end of the transformer winding 21 is connected to the conductor 43 which extends outwardly of the envelope through a seal 39;

After the elements have thus been assembled within the envelope 2|, the same may be evacuated and conditioned for service, as by connecting the envelope with an exhaust pump, the connection being sealed off, as at 15, at the conclusion of the tube conditioning period.

Devices embodying the herein described features have the advantage of including in a single envelope all of the frequency and high voltage apparatus required for the operation of the vtube at high voltage and frequency. The problems of insulation and protection of high voltage and frequency apparatus outwardly of the tube are thus entirely avoided, since the tube of the present invention may be operated from a low voltage source, which, as shown in Figure '1, may comprise a transformer 11 powered from anv energy source, such as a commercial distribution system, at one hundred ten volts and sixty cycles, the transformer 11 being designed to deliver power at, say, one thousand volts for application between the

conductors

43 and 49, and to deliver power at lesser voltages between the

conductors

49, 5I and 53, the conductors 41 and 5| being electrically interconnected outwardly of the envelope, as by reactive means 19, for the control of the oscillator within the tube.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of ther invention, or sacrificing any of its attendant advantages, the form herein disclosed being a preferred embodiment for the purpose of illustrating the invention'. Y

The invention is hereby claimed as follows:

1. An electron ilow device comprising a sealed envelope, an anode and cathode in said envelope, a transformer and oscillator means comprising an electron source, a plate and a gridwithin said circling the conductor v53, one end of the filament 33 being electrically connected with the conductor 5I which extends outwardly of the envelope through a seal 39 in the plate 55.

The transformer 25 comprises the primary winding 21 and the secondary winding 29, both of which comprise helical coils disposed one within the other and both encircling the cathode filament and its support. The transformer coils are each mounted at one end on the frame 65 and extend thence in concentric relationship toward the end of the tube remote from the plate 55. The secondary winding 29 extends beyond the winding 21 and substantially to the end of the tube, and is fitted with a preferably metal shell 13 which forms a mounting for the anode I3, which is thus supported on the .transformer winding 21 in position opposite the cathode I9. The shell 13 thus forms the electrical connection 45 between the transformer winding 29 and the anode I3.

It will be noted that both windingsf21 and 29 of the transformer are commonly connected with 75 envelope, said transformer having a primary winding connected with said plate and outwardly of Athe envelope, and a secondary winding connected between said plate and said anode and supporting said anode, said electron source being connected with said cathode,and means to energize said cathode and said electron source from a power source outwardly of the envelope.

2. An electron flow device comprising a sealed envelope, an anode and cathode in said envelope, transformer and oscillatormeans within the envelope and operatively connected with the anode and cathode, saidl oscillator means .comprising an electron emitting element, said electron emitting element and said, cathode each comprising a lament, said'transforrner comprising co-axial primary and secondary coils, said secondary coil being arranged to encircle the filament of said cathode, and means comprising a common conductor extending outwardly of said envelope for energizing said filaments for electron emission Y `velope having a metal envelope portion forming a mounting, means forming an oscillator plate on said mounting, means on and insulated from said mounting and forming an oscillator grid adjacent said plate, an electron emitting nia-- `ment on and electrically insulated from .said mounting, an anode forming an X-ray generating target, a cathode on and insulated from said mounting in position to deliver electrons on said target, and means forming a transformer comprising windings electrically connected on said oscillator plate, one of said windings carrying said anode and the other having a connection extending outwardly of said sealed envelope.

5. An X-ray generator comprising a sealed envelope having a metal envelope portion forming a mounting, means forming an oscillator plate on said mounting, means on and insulated from said mounting and forming an oscillator grid adjacent said plate, an electron emitting element on and electrically insulated from said mounting, an anode forming an X-ray generating target, a cathode insulated from said mounting in position to deliver electrons on said target, and means forming a transformer comprising windings electrically connected on said oscillator plate, one of said windings carrying said anode and the other having a connection extending outwardly of said sealed envelope.

6. An electron flow device comprising a sealed envelope, an anode and opposed cathode in said envelope, a transformer and oscillator means within the envelope and electrically connected with the anode and cathode, said oscillator means comprising a plate member, said transformer comprising a winding supported on said plate member and in turn carrying said anode in opposing relation with respect to said cathode.

'7. An electron flow device comprising a sealed envelope, an anode and opposed cathode in said envelope, oscillator means within the envelope and electrically connected with theanode and cathode, said oscillator means comprising a shell member forming an oscillator plate, an oscillator grid and electron emitting means enclosed within said shell member, said anode being supported on said shell member in opposing relation with respect to said cathode.

8. An electron flow device comprising a sealed envelope, an anode and opposed cathode in said envelope, transformer means and oscillator means within the envelope and electrically connected with the anode and cathode, said oscillator means comprising a shell member forming an oscillator plate, an oscillator grid and electron emitting means enclosed within said shell member, said transformer means comprising a winding supported on said shell member, said anode `being supported on said winding in opposing relation with respect to said cathode.

zED J. ATLEE.