DE446210C - Device for attaching a glow cathode - Google Patents

Description

GERMAN EMPIRE

ISSUED June 25, 1927

REICH PATENT OFFICE

PATENT LETTERING

M 446210 CLASS 21 g GROUP

N. V. Philips' Gloeilampenfabrieken in Eindhoven, Holland *).

Device for attaching a hot cathode. Patented in the German Empire on June 1, 1924.

The invention relates to a device for attaching hot cathodes in discharge tubes and in particular on the attachment of in the form of an elongated V curved hot cathodes in discharge tubes for relatively high output.

After the previously usual type of attachment, the filament would usually, except for its support wires, nor of supports, which are held on the grid or its girders were worn. The purpose of the invention is now to attach a V-shaped hot cathode completely independent of the other electrodes in the discharge tube close.

According to the invention, a metal support is attached to one of the support wires for the hot cathode attached, and the bent center of the hot cathode is suspended from this support in an electrically insulated manner. Preferably wears the metal support at the end of a tube made of quartz or similar material in which a metal rod to which the bent center of the hot cathode is attached, back and forth agile; is.

In the figures, an embodiment of the device according to the invention is for example shown. It is on a discharge tube with three equiaxed Order attached electrodes applied, in which the anode as a part of the Outer wall of the tube forming metal vessel is carried out.

Fig. Ι is a view of a device provided with a device according to the invention Three-electrode tube.

Fig. 2 is a view of the arrangement of the hot cathode and the grid in the discharge tube according to Fig. 1.

*) The patent seeker stated as the inventor:

Cornell's BoI in Eindhoven.

Claims (2)

Fig. 3 is a section along the line H-II in Fig. 2. Fig. 4 shows a side view of the apex end of the filament with the associated supporting device. The discharge tube shown in Figs. 1 to 4 consists of a hollow metal vessel 2, which can serve as an anode and to which a glass base 1 is fused, which carries an inwardly protruding glass tube 3 at the upper end. The tube 3 runs out into three tubes 4, 5 and 6, which are located next to one another and are hermetically sealed at the end by metal disks 7, 8 and 9. A power supply wire 10 is attached to the disk 8, and this disk carries on the other side a metal frame 11 on which an attachment 12 is attached. A metallic material can be used as the material for the vessel 2 and for the disks 7, 8 and 9, which can be fused with glass in an airtight manner, is not porous and should expediently have the property of releasing as little gas as possible even when the temperature increases permit. Chrome iron of a suitable composition is preferably used for this purpose. The disc 8 and the frame 11 can consist of one piece, and both the frame 11 and the attachment 12 are expediently made of chrome iron. On the attachment 12 are four supports 13; (Fig. 2), which are mutually held in the correct position by a disc 14 attached to the other end. A grid wire 1S is wound helically onto the supports 13. The grid wire can be made of any suitable electrode material. If the grid is exposed to relatively high temperatures, as it is, for. B. occurs in transmission tubes of greater power, the grid wire is expediently made of a metal that is difficult to melt, such as molybdenum or tungsten. The supports 13 can, for. B. made of nickel. If the grid is exposed to high temperatures, they can also consist of chrome iron, molybdenum or tungsten. The supports are by means of. Nuts 16 attached to the attachment 12. The attachment 12 is attached close to the wall of the vessel 2, so that the interior of the vessel 2 is fairly closed off from the space in the glass vessel and little or no electrons can escape from the vessel 2. ! The outer tubes 4 and 6 are used to carry and airtight insertion of the support wires for the filament. The support wires can be passed through the disks 7 and 9. However, they are expediently attached to the panes on both sides, for example by welding. As the figure shows, power supply wires 20 and 22 (Fig. 1), e.g. made of nickel, are attached to the disks 7 and 9, and wires 21 and 23, e.g. B. made of copper attached. The support wires 24 and 25 for the filament are attached to the other side of the discs and carry the two legs of the filament 26 (Fig. 2). The attachment of the bent end of the filament is shown in Figs. 2 and. 4 can be seen. A metal support 27 is attached to the support wire 24 and carries at the lower end a metal clamp 28 which holds a glass tube 29 in place. In the glass tube a rod 30 is displaceable back and forth, and the vertex of the thread is now on this tube in a suitable manner, e.g. B. by a binding wire 31 attached. This suspension of the filament prevents it from bending and coming into contact with the grid. The discharge tube is used with the metal vessel 2 down; If now the filament becomes hot during operation and expands, the rod 30 pushes itself slightly downwards in the tube 29, while the rod 30 can move freely upwards again when the filament cools. The number of glass side tubes can of course also be changed as required, taking into account the number of electrodes to be attached, Pa τ je ν ta ν s ρ RtJ c he: 1. Device for attaching a hot cathode in the form of an elongated one V in a discharge tube, characterized in that at one of the Support wires for the ends of the hot cathode are attached to a metal support to which the bent center of the hot cathode is attached is suspended electrically insulated. 2. Apparatus according to claim r, characterized in that the metal support at the end an isolated one. Carries a tube in which a rod on which the bent center of the hot cathode is attached, is movable back and forth. 1 sheet of drawings.