US2134577A - Electrode system - Google Patents

Description

Oct. 25, 1938. PUTZER 2,134,577

ELECTRODE SYSTEM Filed July 22, 1937 WITNESSES: INVENTOR A/fred Pufzer ATTORNEY Patented Oct. 25, 1938 ELECTRODE SYSTEM Alfred Piitzer, Berlin-Spandau, Germany, asslgnor to Siemens & Halske Aktiengesellschatt, Siemensstadt, near Berlin, Germany, a corporation of Germany Application July 22,

1937, Serial No. 154,952

In Germany July 23, 1936 5 Claims.

The invention relates to discharge devices and especially to suchidevices utilizing a hot cathode.

An object of the invention is to conserve heat energy applied to a hot cathode of a discharge device.

Another object ofthe invention is to prevent back-iires in hot cathode devices.

Other objects and advantages of the invention will be apparent from the following description and drawing, ginwhich:

Figure 1 is a view partly in cross section of a preferred embodiment of the invention, and

Figs. 2 and 3 arem'odifications of the invention disclosed in Fig. 1. I

Specifically stated, the invention concerns the utilization of curved reflectors or shields or caps about the ends; of a hot cathode for the purpose of conserving the heat and to provide a more uniform temperature throughout the length of the cathode. At the same time, the shields are located intermediate between the two main electrodes and back-fire from the anode or an and preferably is in-the form of turns extending from one end it to the other end l5 where both are connected to the standards II and I2. About the ends I 4 and 15 are placed curved shields or disks l6 and I1, preferably in conical shape. It is preferred to utilize two anodes l8 and i 9 although the invention is applicable to a single pair of main electrodes. These anodes l8 and H! are preferably annular rings with central openings 20 and H and these anodes are supported on the standards and leads 22 and 23. It is preferred to have the conical shields l6 and ll located with their apexes 24 and 25 extending within the openings 20 and 2| of the anodes.

Inasmuch as the device is particularly adapted to gas or vapor filled devices, such as the noble gases or mercury vapor, it is preferred to locate the reflectors or shields l6 and I1 within the mean free path distance oftheir respective anodes l8 and I 9, in order that there may be no, discharge therebetween. The conical shields or reflectors l6, I! are preferably supported directly upon the cathode standards II and I2 and may have a poor heat conducting connection thereto (Cl. 2502'l.5)

at 26 and 21. Inst/ead'the reflector shield may be made of poor heat conducting material.

any event, the shields are preferably very smooth on their surface and are preferably highly pol-.

ished towards the cathode at least in order to reflect heat back to the turns.

It will be noted that the cathode will be prevented from radiating heat to the side walls of the tube, except for the small space between the two conical reflectors that is left for the passage of electrons to the anodes.

Inasmuch as the shields are intermediate the anode and cathode, a' direct back-fire from one to the other is likewise prevented.

In Fig. 2, there is disclosed a modification in l6 and H. and be of a solid instead of a This electrode may take other forms mesh construction supported on a lead-in standard 29.

In Fig. 3, there is disclosed a still further modification in which two control grids 30 and 3| are disclosed as hollow members preferably in a mesh form with central openings 32 and 33 placing them about the conical shields l6 and H.

Fig. 3, the mesh of the grids lies in the electron path from the cathode i3 around the edges of the curved reflectors to the anodes.

It will be noted that in the various figures, the standards and lead-ins can be located axially aligned.

all in one plane on the press it) and that the electrodes are The reflectors prevent the cooling that would otherwise take place at the ends of the cathode due to radiation. Because the anodes are ringshaped and the caps penetrate the rings, space is saved and the arrangement is easily mountable.

By the ring-shaped construction of the anodes, their radiation surface is increased, their temperature is maintained lower and the danger of back-fire is decreased. No particleoi cathode coating can be sputtered directly to the anode because oi. the shield.

The hot cathode is preferably a" helix with a coating of good electron emissive material.

The

This is advantageous during the manufacture,

and for gas filled discharge vessels it is desirable for the sake of attaining a the space charge.

better removal of While there has been shown preferred embodiments of the invention, it is apparent that many changes may be made in the shape, arrangement and number of the elements. Accordingly, it is desired that only such limitations be imposed on the following claims as is necessitated by the prior art.

I claim as my invention:

1. A discharge device comprising an annular anode, an incandescible cathode and a curved reflector around one end of said cathode and extending within said annular anode.

2. A discharge device comprising an annular anode, a cathode and a conical member having its apex extending within said annular anode and its edges around a portion of said cathode.

3. A discharge device comprising an anode having an opening therethrough, a conical member having its apex extending within the opening in said anode, a cathode, said conical member having its edges around a portion 01 said cathode.

4.. A discharge device comprising a cathode, anodes having openings therein and positioned adjacent the respective ends of said cathode and conical reflectors intermediate said anodes and said cathode and having their apexes within said anode openings.

5. A discharge device comprising an annular anode, an incandescible cathode, a curved reflector intermediate said cathode and said anode and an annular control electrode located in the discharge space between said anode and cathode.

ALFRED PfiTZER.

Images