US3558969A - Electron discharge tube having an anode forming part of a lecher-line with a heat dissipating element - Google Patents

Abstract

A high-power electron discharge tube having an anode forming part of a Lecher line and being cooled by heat dissipation. Means to dissipate the heat generated by the anode are located at a voltage node or at a current antinode, i.e., a point at which, for a given frequency, the voltage is a minimum and current a maximum.

Description

United States Patent lnventor App]. No. Filed Patented Assignee Priority Otto G. Voss Ahrensburg Scheunenkoppel, Germany Dec. 9, 1968 Jan. 26, 1971 U. S. Philips Corporation New York, NY.

a corporation of Delaware Dec. 13, 1967 Germany ELECTRON DISCHARGE TUBE HAVING AN ANODE FORMING PART OF A LECHER-LINE WITH A HEAT DISSIPATING ELEMENT 4 Claims, 2 Drawing Figs.

U.S. C1 315/39, 33/82; 331/91 313/42, 313/46 Int. Cl I-IOlj 7/46,

HOlj 19/80 [50] Field of Search 333/82A.

82BT, 83T; 313/4246; 315/39; 331/99, 100

[56] References Cited UNITED STATES PATENTS 2,151,912 3/1939 Habann et a1 333/82AX 2,265,833 12/1941 Fritz 333/82A 2,285,662 6/1942 Hutcheson 313 4 2,505,251 4/1950 Knol et a1. 333/82AX 2,735,941 2/1956 Peck 333/82AX Primary Examiner1-lerman Karl Saalbach Assistant Examiner-Saxfield Chatmon, Jr. Att0rneyFrank R. Trifari ABSTRACT: A high-power electron discharge tube having an anode forming part of a Lecher line and being cooled by heat dissipation. Means to dissipate the heat generated by the anode are located at a voltage node or at a current antinode, i.e., a point at which, for a given frequency, the voltage is a minimum and current a maximum.

PATENTEU JAN 26 I97! INVENTOR.

OT TO 6. VOSS AGEN ELECTRON DISCHARGE TUBE HAVING AN ANODE FORMING PART OF A LECI-IER-LINE WITH A HEAT DISSIPATING ELEMENT The invention relates to a high-power discharge tube suitable for wavelengths in which the elements determining the frequency are distributed along the conductors, the tube comprising a device which cools the anode by heat dissipation.

The cooling of the anode of tubes for high power and high frequencies has always experienced great difficulties, since the anode conveys not only a high direct voltage, but also highfrequency voltages. The requirements imposed upon a good thermal contact of the anode with the cooling medium and upon a good insulation therefore were contradictory.

In German Patent Specification No. 837,577, for example, an electron tube is described in which heat of the anode is conducted through a supply conductor in the form of a pin to a cooling device outside the tube. The coefficients of expansion of the materials were chosen to be such that the contacting surfaces of the pin and the cooling components were forced more strongly against each other upon heating so that the transfer of heat improved at higher temperatures. However, such a construction is not suitable for very high frequencies, because they disturb resonance circuits.

It is furthermore known from Us. Pat Specification No. 3,054,012 to construct a tube entirely from ceramic components, the anode consisting of a metal law layer which is formed on a ceramic part of the wall. The ceramic parts have a large wall thickness so that they readily dissipate the heat to a cooling member.

However, such large ceramic bodies cause considerable dielectric losses when they are arranged in the vicinity of components which convey large high-frequency voltages. Therefore, this embodiment is not suitable either for discharge tubes, in which the elements which determine the frequency are distributed along the conductors for example, in tubes in which the anode forms part of a Lecher system.

The said drawbacks can be avoided in an electron tube for high power and for a frequency range in which the elements which constitute the oscillatory circuit are distributed along the line(s), the tube comprising an anode which is cooled by heat dissipation, if, according to the invention, the anode which forms part of a Lecher system is cooled by dissipating the heat at a location of the Lecher system, where the high frequency voltage shows a minimum.

At this location the high frequency current will generally show a maximum.

The anode itself may be constituted as a Lecher system. In

order to reduce the dimensions of the Lecher system a tuning capacitor may be providedv The invention will be described with reference to the accompanying drawing, in which:

FIG. I is a longitudinal sectional view of a tube having an anode which constitutes a Lecher system; and

FIG. 2 shows a similar sectional view rotated through with respect to FIG. I.

Referring now to the FIGS., reference numeral I denotes a ceramic wall of the tube which is sealed by a bottom plate 2. in the vacuum space 3 there is a cathode 4, a control grid 5 and the anode which consists of two strip- shaped parts 7 and 8 which constitute a Lecher system outside the envelope I and which system is terminated by a conductor 11. In order to reduce the dimensions of the Lecher system, a tuning capacitor 15 is provided which can be tuned by means of the shaft 14. The strips 7 and 8 are passed through the envelope 1 in a vacuumtight manner at 9 and 10. The terminal conductor 11 is located in a region where the high-frequency voltage shows a minimum and is in a good heat-conducting connection with an insulating member 12 which is connected to a cooling member 13. This cooling member 13 comprises cooling tins 16. The shorter the Lecher system, the lower the thermal resistance of the active anode parts to the terminal conductor 11, and hence the better the heat dissipation to the cooling member 13 and the lower the anode temperature. As shown in FIGS., the conductors 7 and 8 are strip-shaped. Since the cooling member is not located near a part with a large highfrequency alternating voltage, it causes no extra losses.

I claim:

1. A high-power electron discharge tube for a frequency range in which the elements which constitute an oscillatory circuit are distributed along a line, the tube comprising an anode which is cooled by heat dissipation and which forms part of a Lecher system having two conductors that are shorted at the terminal opposite to the terminal integral with said tube anode, and means to dissipate the heat mounted on and in thermal contact with said shorted terminals at the said shorted location of the Lecher system where the high-frequency voltage shown a minimum.

2. An electron tube as claimed in claim 2, wherein the heat dissipating means is at a location where the high-frequency current is maximum.

3. An electron tube as claimed in claim 1 wherein the anode is constituted as a Lecher line.

4. An electron tube as claimed in claim 3, wherein the dimensions of the Lecher system are kept comparatively short by the addition of a tuning capacitor.

73 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,558,969 Dated Januar 26, Q71

lnven y OTTO G voss It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 5, after "high-power" insert -electron Signed and sealed this 11th day of May 1971 (SEAL) Attest:

EDWARD M. FLETCHER,JR. WILLIAM E SCHUYLER t Attesting Officer Commissioner of Patenw

Claims (4)

1. A high-power electron discharge tube for a frequency range in which the elements which constitute an oscillatory circuit are distributed along a line, the tube comprising an anode which is cooled by heat dissipation and which forms part of a Lecher system having two conductors that are shorted at the terminal opposite to the terminal integral with said tube anode, and means to dissipate the heat mounted on and in thermal contact with said shorted terminals at the said shorted location of the Lecher system where the high-frequency voltage shown a minimum.

2. An electron tube as claimed in claim 2, wherein the heat dissipating means is at a location where the high-frequency current is maximum.

3. An electron tube as claimed in claim 1 wherein the anode is constituted as a Lecher line.

4. An electron tube as claimed in claim 3, wherein the dimensions of the Lecher system are kept comparatively short by the addition of a tuning capacitor.

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