US2436649A - Electron tube of the toroidal type - Google Patents

Description

Feb. 24, 1948.

I. M. KANE ELECTRON TUBE OF THE TOROIDAL TYPE Filed May 6, 1946 INVENTIOR [rWl'Jz A1. Kane. BY 1%; h- Goa-a ATTORNEY Patented Feb. 24, 1948 ELECTRON TUBE OF THE TOROIDAL TYPE Irwin M. Kane, Brooklyn, N. Y., assignor of onehalf to Charles H. Strange, White Plains, N. Y.

Application May 6, 1946, Serial No. 667,672

4 Claims. 1 This invention relates to a new and better time of electronic tube.

One object of my invention is to provide an electronic tube that because of its shape permits greater cooling surfaces than heretofore.

One object of my invention is to provide an electronic tube which will carry relatively great power for its size.

Another object of my invention is to provide an electronic tube of relatively compact dimensions which can supply large amounts of high frequency power when used in circuits designed to generate high frequency currents.

A further object of my invention is to provide an electronic tube which will have an extraordinary life period under strenuous operating conditions.

A still further object of my invention is to provide an electronic tube of new and novel design.

Other objects and advantages of this invention will become apparent as the specifications proceed.

In the drawing in which similar numerals indicate corresponding part-s;

Figure 1 is a plan of m tube having fragmental portions thereof removed,

Figure 2 is a cross-sectional schematic sectional view of the tube of Figure 1,

Figure 3 is a side elevation of a modification of my tube and Figure 4 is a transverse sectional view of the modification of Figure 3, the section being taken substantially along the line 4-4 of Figure 3.

Referring to the embodiment as shown in Figures 1 and 2, an annular or ring shaped electron emission element, cathode, or filament l, which is of such size as to ofier a large emission surface is almost completely surrounded by a hollow toroidal grid 2, thereby ofiering complete and definite control over electron emission from the filament to an external anode 3. This feature makes for transconductance, or the ratio of change of the anode current to change of grid potential, of a high value, which is desirable.

The filament is supported by supports 4 and 4 passing through holes 5 in the lower portion of the grid 2, so as to prevent substantial electrical contact between the supports and the grid.

The external anode 3 is annular and of inverted U-shaped cross section and is constructed of metal, preferably copper. This external annular shaped anode is extremely desirable because it permits a large plate surface for the reception of tremendous electron emission. Another definite advantage is the large external 2 surface area of the anode which makes for greater and more rapid cooling either by a water jacket or by radial fins covering the complete external surface of the anode for cooling by a forced air draft.

The interior of the anode is sealed off from the exterior by means of closure 6 of glass or other suitable material, the anode and closure being joined by a glass to metal seal 1 so that the anode and closure form a gas-tight envelope. The preferred shape of the closure is annular and of U-shaped cross section complementary to .the anode so as to permit a smooth vertical flow of cooling air past the envelope.

The grid is supported by a plurality of supporting posts 8 anchored in the closure 6. One of such posts 8 passes gas tight through the closure and is provided with a prong 9 for an external connector and serves the double function of a support and conductor.

In a similar manner the filament supports 4 and 4' pass through the closure and are provided with connector prongs l0 and Ill.

While I have shown the filament as a con-' tlnuous ring for a divided flow of current between its two halves from one prong to the other it is obvious that other types of filaments may be used if suitable supports are used.

My invention when applied to high frequency generators or communication transmitters will, in a manner well known in the art, give relatively large amounts of power with due regard to the overall size of the tube than that now obtained with the conventional types being utilized at present due to the shape which lends itself to larger cooling area than heretofore experienced.

Figure 3 shows another embodiment of my invention which comprises a water cooled anode which, because of this new and novel application of cooling, will enable the tube to carry much higher currents than tubes used now for the purpose for which my tube is designed, i. e., as an oscillator for high frequency current generation, or other electronic applications.

The shape and construction of the embodiment shown in Figures 3 and 4, save for the anode elements, are similar to those of a conventional tube. My tube thus shown comprises a filament la and grid 2a surrounded by an anode 3a, all enclosed in an envelope 4a. The anode 3a comprises a tightly wound coil 5a of metal tubing 6a. Adjacent turns of the coil are brazed skin-to-skin thereby forming a continuous cylinder surrounding the grid as does the plate of a conventional thermionic tube.

The end portions of la and 8a of the tubing 6a pass gas tight through the envelope 4a by glass to metal seals known to the art and serve as outlet and inlet connectors to a cooling water circulator, not shown. Strain on the seals due to Weight of the anode is relieved by stays 9a. Electrical connection to the anode may be eifected in a number of ways such as by means of an anode cap 10a.

When either of my tubes is constructed as a gas filled tube other advantages are obtained. Due to the high cooling ability of the plate or anode, the gas in the tube will not readily be absorbed by the anode, thereby insuring a longer life period for the tube.

The invention claimed is:

1. An electronic tube comprising a hollow metallic anode, an annular cathode in the hollow thereof, and an annular grid intermediate of the anode and cathode, the anode, cathode and grid substantially having a common axis.

2. Adoughnut shaped electronic tube comprisingan insulating envelope section and an enclosing external anode sealed thereto, the section and anode forming an envelope, a cathode adapted to be heated, a grid and requisite connection leads passing through the insulating envelope section, the internal elements of the tube being annular shaped and enclosed in a doughnut or torus shaped envelope said section being of insulating material forming a base, the upper portion of the envelope consisting of an electrically conductive material sealed to the lower portion and forming an external anode.

3. An electronic tube comprising an envelope shaped in the form of a doughnut or torus, the lower portion of which consists of insulating material and the upper portion of conducting material which functions as an external anode sealed to the lower portion, and internal elements comprising a cathode and a grid annular shaped to conform to the envelope, the contents of the tube permitting transconductance between anode REFERENCES CITED The following references are of record in the file of .this patent:

UNITED STATES PATENTS Name Date- Acheson Apr..24, 1934 Number

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