US2204026A - Antenna stay arrangement - Google Patents

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June 11, I FETERS. v I

- ANTENNA STAY ARRANGEMENT Filed Nov. 19, 1958 2 Sheets-Sheet 1' INVENTOR W/LHELM PETERS BY Ju 11', v

ANTENNA STAY-ARRANGEMENT Filed Na -7,19, 193a 2 Sheets-Sheet? INVENTOR W/LHELM PETERS ATTORNEY w: PETE-Rs 2,204,026

Patented June 11, 1940 T I UNITED STATES ANTENNA STAY ARRANGEMENT Wilhelm Peters, Berlin, Germany, assignor to,

.Telefunken Gesellscliaft fiir Dralitlose Telegraphie m. b. 11., Berlin, Germany, a corporat tion of Germany Application November 19, 1938, Serial No. 241,34: 1

In Germany November 24, 1937 Claims. (01. 250-33) The invention is concerned with an arrange ment designed to stay antenna masts or poles in a way so as to render them upset-proof, especially for self-radiating mast antennae. Antennae, 5 whether for sending or receiving, must be of a ,certain height. A recent development in the art hasbeen the use of self-radiating iron masts of great height for sending. They are generally supported and stayed by cables. For the preloll vention of resonance of the cables or stays with the transmitted wave, they are divided by insulators spaced predetermined distances apart. Where large radiation antenna currents are dealt with, the antenna masts present a high poten- -tial to ground. This makes the conditions or duties for. the strain insulators particularly se- Vere, for occasionally working voltages over 100 kilo-volts are encountered.

Inasmuch as the field intensity, especially in the neighborhood of these rod orbar-shapedantenna drops sharply with distance, the insulator located in the immediate neighborhood of the antenna is subject to particularly high voltage stresses. Hence, its fiashover distance must be made especially long. Moreoventhe demand is that its capacitance should be as low as possible in order that stray or parasitic currents in the stay cables may be minimized. From an electricalviewpoint, pin or rod insulators are most preferable, for there is no doubt that they satisfy the requirements most closely, in contrast to what is true of transom suspension or strain arrangements comprising egg or saddle type insulators.

However, from the mechanical viewpoint certain objections arise against the use of rod or pin type insulators for inthe event of breakage of such insulators the connection between the mast and the stay cable is severed, with the result that the mast may tumble down. As a mat ter of fatigue, insulators will be destroyed not only as a result of fatigue in the material, but also due to heat and cold strains in violent changes of weather or also by lightning disdharges.

heavy span rope or cable stays are still in place,

ing cables suffering breakage simultaneously. In other words, the essential feature of the invention is that in the case of rupture or breakage of an insulator, to rely upon the insulators in the z I other stay, ropes or cables to assist in the safe supporting of the mast in order to prevent the mast from upsetting 0r tumbling down.

Figures 1 and 2 show an exemplified embodiment of the invention in elevation and plan,

while Figures 3 and 4 illustrate a modification g of the invention in elevation and plan, while Figure 5 illustrates the use of the arrangement of Figure 4 for voltage measurement. In Figure 1, the mast i is erected on and insulated from ground. It is held in the proper position by the aid. of the span or stay ropes or cables 2, 3, 4. The stay or span cables are attached to the mast by the aid of stick insulators 5, 6; I, while in addition they areinter-connected by the accessory or auxiliary cables 8, 9, 10, at points immedi- 20 ately below the insulators.

Now, incase of breakage of an insulator, say, insulator 6, thestay cable 3 which is directly affected, will still stay connected with the mast by way of the cross cables 8 and H] with the ring line and the insulators 5 and l withthe mast. This will preclude all risk of such serious an accident as tilting or tipping over. All that will happen is that the mast may assume a slightly sloped or leanin position; but it will still stay 3 in operating condition. The replacement of the faulty insulator may then proceed with all necessary care and without hurry, and the work is not attended with particular difficulty because the in fact, the lnastis restored to its regular position to mount a new insulator by means of an auxiliary rope. I If desired, the ring line may be divided by insulators. Finally, in case of consecutive breakage of all insulators, the holding or staying of the mast may be effected with the span ropes by the aid of distinct catch hooks H I2, is, as indicated in the drawing. In order to render the tensile stress set up in catching more gentle, spring elements may be inserted in the 45 span ropes.

However, the invention here disclosed offers certain advantages also in electrical respect. As pointed out above, the electrical field of the aerial which arisesbetween it and the ground, exhibits a particularly steep drop in the vicinity of the mast. The result is that the voltage drop at the insulators in the neighborhood of the mast. is particularly high. Due to the convenient capacitance or this ring tothe antenna mast, by

' choosing suitable cable diameters of the ring rope (8, 9, I 0), the drop of potential at the first insulator may be diminished. In fact, by the aid of additional rings, such as that formed by the cross-connecting cables 8', 9 and Ill along the span ropes disposed after additional strain insulators or terminal insulators, the whole voltage drop may be given a form satisfying any law so as to result in any desired uniform rate of voltage drop. The stray'or parasitic currents may be 'cut down by multiple insulation along the stay cable. To relieve the uppermost and most heavily loaded insulator of electrical stress results in a by no means unessential technical advantage inasmuch as the flashover length or distance of the insulator, especially in the case of high-frequency, rises much more markedly than the potential so that at this particularly endangered point, by the ways and means already mentioned, it becomes possible to choose a smaller insulator which may be manufactured so as to withstand high breaking stresses without any difficulties. Anbther scheme would be to mount corona rings on the insulators to shape the electrical potential gradient at will. However, they would have to be of considerable size to be effective and, as a result, the mechanical stress rises and the. danger due to ice and sleet increases.

Another exemplified embodiment according tothe invention is illustrated in Figures 3 811614. To secure the span ropes or stay cables there is here employed an insulator comprising two conical halves M, 5, which entirely surrounds the mast, and which is fastened to the latter by the aid of supporter rings is, ll. The equator line of the resultant double cone structure is surrounded by a metal ring I8 to which the span ropes are fastened by means of hooks. 7

Finally, the arrangement may also be used for thevmeasurement of the electrical field on the mast in that, as shown in Figure 5, a measuring instrument A is mounted between themast and the ring conductor surrounding the mast, the said instrument to indicate the charge current or the potential difference.

I claim: 1. An antenna comprising a vertical radiating mast, a plurality of stay cables for supporting said mast, said cables being connected to said mast through insulating means, an auxiliary support ing means connecting said stay cables at the upper ends thereof whereby the breakage of said insulating means will not disconnect the stay cable associated therewith from said mast, said auxiliary supporting means being so disposed with respect to said mast that a predetermined potential gradient is maintained in the vicinity of said mast.

2. Arrangement as claimed in claim 1, with the characteristic feature that for the measurement of the field intensity or potential a measuring instrument is interposed between mast and the auxiliary supporting means;

3. An antenna comprising a vertical radiating mast, insulating means connected to said mast ata pointnearest its top, stay cables connected between said insulating means and the ground and means connecting the upper ends of said stay cables together whereby in the event of the failure of said insulating means between the mast and a stay cable, said cable is maintained in position, said connecting means being so disposed with respect to said mast that a predetermined potential gradient in the vicinity thereof is maintained. 1

4. An antenna comprising a vertical radiating mast, a plurality of stay cables for supporting said mast, said cables being connected to said mast through insulators and a plurality of auxiliary supporting means connecting said stay cables at the ends of said insulators remote from said mast whereby the breakage of an insulator will not disconnect the stay cable associated therewith from said mast, said auxiliary supporting means being so disposed with respect to said mast that a predetermined potential gradient is maintained in the vicinity of said mast.

5. An antenna comprising a vertical radiating mast, a plurality of stay cables for supporting said mast, said cables being connected to said mast through insulators and a plurality of conducting rings connecting said stay cables at predetermined positions along said cables, said cables being electrically discontinuous between said 0011- 153- ducting rings whereby a predetermined potential field about said mast is maintained.

WILHELM PETERS.

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