DE1191495B - Traveling field pipes with a spiral-shaped delay line - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

HOIj

German KL: 21g -13/17

Number: 1191495

File number: E17320IX d / 21 g

Filing date: March 17, 1959

Opening day: April 22, 1965

The invention relates to a traveling wave tube with a helical, with the electron beam of Tube coaxial delay line, with a number of axially parallel insulating rods that rest on the Lay the delay line and touch its outside in a number of points, as well as with one of the rods with the intermediate helix surrounding the tensioned helical shape Winding.

It is already known to have a helical ver * o to hold the delay line by means of axially parallel insulating rods. In a known arrangement in this way the bars are glazed before assembly. After hanging up on the Spiral, the glass is melted by the supply of heat, whereby it flows around the contact points around the wire of the spiral and Establishes a firm connection between the rods and the delay line after cooling. The production of such an arrangement is ao but associated with great expenditure in terms of equipment and time. The partial glazing of the helix also leads to increased electrical losses.

In another known arrangement, as the axially parallel insulating rods by means of a glass ribbon that is wound in a helical shape in the soft state held together. The winding is done in such a way that the delay line and the Laying-on insulating rods, mounted on a slow-running lathe, slowly is rotated, wherein a glass ribbon is fed past a flame. The the ribbon of glass softening flame is moved continuously in axial direction with the supplied glass ribbon, so that helical windings arise, which consist of strongly curved areas on the rods and rectilinear areas exist between the bars. So the winding has a polygonal one Cross-section. When it cools down, tensions arise in the glass ribbon winding that holds the insulating rods Press firmly against the delay line.

The application of the glass ribbon winding to the structure consisting of insulating rods and delay line is therefore also associated with considerable expenditure in terms of equipment and time. Each structure must be clamped separately and wound at low speed. In addition, there is the need for a constant supply of energy to soften the glass ribbon. The feeding of the glass ribbon is also associated with difficulties, since this continuous wanderfeid tube with a helical one during winding
Delay line

Applicant:

English Electric Valve Company Limited,

London

Representative:

Dr. W. Müller-Bore and Dipl.-Ing. H. Gralfs,

Patent attorneys, Braunschweig, Am Bürgerpark 8

Named as inventor:
Thomas Henry Staerck,
Chelmsford, Essex (UK)

Claimed priority:
Great Britain March 18, 1958 (8712),
dated December 5, 1958

must be moved nuierlich in the axial direction. When unwinding the glass ribbon from a supply roll Of course, heating must also take place, because otherwise the bond would break. Finally, it comes with the manufacture of the known arrangement on an exact coordination of the degree of softening of the glass ribbon and that during winding on this exerted tensile forces, on the one hand, a poor contact of the glass ribbon on the insulating rods and on the other hand to prevent constriction or even tearing of the glass ribbon. It is it is clear that such a cumbersome process for mass production of traveling wave tubes is not suitable.

The aim of the invention is a traveling wave tube with a helical delay line of the introduction mentioned genus, which can be produced in a very simple manner without accepting electrical disadvantages so that it is particularly suitable for mass production. In particular, the production of traveling wave tube according to the invention can take place without the particularly expensive heating, which is always required when assembling the known arrangements.

For this purpose, the invention provides that the winding is a helical spring with a circular cross-section is made of metal, which in the unstressed state has a smaller inner diameter than an imaginary one

;. s: .5. r ■: · ■ - ■■ · =: * 509 540/276

Cylinder that envelops the rods. The traveling wave tube according to the invention can therefore be produced simply in that the screwed- on helical spring is pushed onto the insulating rods and then relaxed. Surprisingly, the metal spring arranged according to the invention does not affect the electrical properties of the traveling wave tube in any way.

It is already known, in the case of a special tube, to wind a metal wire helically onto a glass envelope that defines the helical delay line. However, this additional winding has the purpose and effect that the electrical properties of the traveling wave tube are significantly influenced; namely, the bandwidth of the known tube is considerably reduced by the auxiliary winding. Since one of the most important advantageous properties of a traveling wave tube, however, is precisely the extraordinarily large bandwidth, the specialist is prevented by the known special tube from using an additional metal winding in conventional broadband traveling wave tubes.

It should also be emphasized that in the known traveling wave tube mk trimmed Fre quenzband is not thought of the additional winding as a helical spring, ie as an elastic • structure.

The invention is described below, for example, with reference to the drawing, which illustrates only the part of a traveling wave tube improved according to the invention. In the drawing shows

F i g. 1 is a partially sectioned side view of a traveling wave tube according to the invention, which is broken off in the middle and at the ends , and

F i g. FIG. 2 shows a cross section of the FIG. 1 shown object.

According to the drawing, the traveling wave tube has a helical delay line 2 between end members 3 within a cylindrical shell 1. The filament 2 coaxially surrounds the electron discharge path (not shown), which runs in a conventional manner axially within said filament.

The helix 2 is held by three insulating rods 4, 5 and 6 at intervals of 120 ° on the circumference of the helix, which touch them in three lines parallel to the axis.

In order to simplify Fig. 1, the rod 6 is not shown therein, but only the rods 4 and 5. Said rods are coated over desired sections of their length with graphite or another suitable resistance material to attenuate according to the known technique of traveling wave tubes to convey. Such a graphite coating is only indicated in FIG. 7 on rod 4 and not shown in the other rods, again to simplify the illustration in FIG. 1.

According to the invention, the rods 4, 5 and 6 by a coil spring made of metal 8 with their insides pressed against the helix 2. This feather is so long that it is at least about extends the greater part of the length of the delay coil 2 and in the untensioned state has a slightly smaller inner diameter than that of an imaginary circle that the rods 4, 5 and 6 circumscribes and which these rods touch on the inside. In Fig. 1 is the spring 8 with respect to the coil 2 shown wound in opposite directions. Of course, this is not necessary, and it actually becomes the same Direction of winding for coil 2 and spring 8 is generally preferred. For attaching the coil spring 8 the rods 4, 5 and 6 are brought into their position, and the spring 8 is wound up somewhat, so as to to enlarge the inner diameter sufficiently that it slipped over said rods 4, 5 and 6 can be. It is then released in the required position. It is clear that the pen is after the release exerts radially inwardly directed forces that the rods 4, 5 and 6 inwardly against the Press spiral 2 and fix the latter precisely and stably. It is further noted that the by the spring 8 exerted inward compressive forces with a high degree of approximation uniformly are over the entire length of the spring, so that a very good and stable mounting and clamping is achieved will.

Claims (1)

Claim: Traveling wave tube with a helical, coaxial with the electron beam of the tube Delay line, with a number of axially parallel insulating rods on the delay line and touch the outside in a number of points, as well as with one the rods with the one in between Tensioned helical winding surrounding the helix, characterized in that that the winding is a helical spring (8) with a circular cross-section made of metal, which in the unstressed state a has a smaller inner diameter than an imaginary cylinder that envelops the rods. Considered publications:
British Patent No. 786,453;
U.S. Patent No. 2,773,213. 1 sheet of drawings 540/276 4.65 Q Bundetdiuckend Berlin