US2014784A

US2014784A - Wave antenna

Info

Publication number: US2014784A
Application number: US679926A
Authority: US
Inventors: Charles E Schuler
Original assignee: INT STACEY CORP
Current assignee: INT STACEY CORP; INTERNATIONAL-STACEY Corp
Priority date: 1933-07-11
Filing date: 1933-07-11
Publication date: 1935-09-17
Anticipated expiration: 1952-09-17

Description

Sept. 17, 1935.

C. E. SCHULER WAVE ANTENNA Filed July 11, 193

10 fiarZesZJcZzzZer Patented Sept. 17, 1935 UNITED OFFIQE WAVE ANTENNA Application July 11, 1933, Serial No. 679,926

5 Claims.

This invention relates to a vertical antenna suitable to radiate radio signals and its principal object is to improve the transmission thereof. A further object is to obtain an improved type of a vertical antenna suitable for radiating electro-magnetic waves.

In radio broadcasting, it has been customary to erect two towers and connect them together by a horizontal wire. From this wire, there is suspended a vertical cage antenna at half Way between towers, and anchored to ground at the other end. The difficulties encountered heretofore with this arrangement are as follows:

(a) Antenna systems for the higher wave lengths in the broadcast band become very costly on account of the very tall supporting structures which are required.

(b) The presence of the two towers distorts the broadcast pattern.

(c) Power losses due to absorption of energy.

My invention obviates the above objections by providing a self-supporting mast or tower, the top portion of which acts as a radiator of electromagnetic waves and the bottom of which supports in addition a wire antenna bonded to the top portion of tower. The structure is mounted on insulators at the base and at intermediate points, and consists substantially of four or more leg members, interconnected by bracing members. The upper or radiating portion of the tower is insulated from the lower supporting portion of the tower preferably at a point proportionally related to the length of the operating wave, whereby the insulated plane between the tower portion will be theoretically at a minimum voltage value. Adjacent to the insulating plane, there are attached to the upper portion of the tower several wires which are brought to a point atthe ground line, and are isolated therefrom by a tension insulator of conventional construction. This group of wires forms the lower part of the antenna, and is connected to the coupling system of the transmitter circuit.

Other insulators are inserted into the tower legs at various points to break up the tower into sections electrically insulated from each other. The length of these sections should preferably be not more than one-eighth of the operating wave to eliminate re-radiation of the supporting structure. Making the radiating portion of the mast equal for instance to one-quarter of the operating wave, places the insulators such that they are subjected to a minimum amount of electrical strain, permitting the use of comparatively inexpensive insulators of conventional design.

My invention provides an antenna tower in which mechanical stresses can be readily determined by ordinary methods used in mechanics and does not depend on secondary supporting means such as guy wires, or the like. In addition, it provides for relatively simple erection by ordinary means. 7

A further object resides in the provision of an outrigger placed on top of the radiating portion of the tower from which there are suspended at number of wires which extend and are attached to the base of said radiating portion. This outrigger consists of a plurality. of horizontal structural members suitably attached at or near the top of the tower and are bonded thereto for electrical efficiency.

An antenna made in accordance with my invention involves considerable reduction in ground space required with the resultant saving of cost for land, in comparison with the guyed structure 1 requiring large plots to accommodate guys or other secondary supports. Also, I use less expensive insulators than those used in guyed structures as well as a fewer number in order to further reduce cost.

For a further understanding of the invention, reference is to be had to the following description and the accompanying drawing, wherein:

Fig. 1 illustrates a side elevation of an antenna made in accordance with the present in- 2 vention;

Fig. 2 is a plan view thereof;

Fig. 3 is a transverse horizontal sectional view on the line III-III of Fig. 1.

Referring more particularly to the drawing, the 3 numeral l designates my improved antenna mast in its entirety. The portion of the mast from the plane indicated at B to the top of the mast constitutes the radiating portion of the tower. Elec-. trical conductors 8 are connected with the lower part of the radiating portion of the tower and extend from the plane B down to the point C, converging from the lower part of the active antenna. The tower from the plane B to the ground forms the supporting portion and, electrically considered, is not a part of the active antenna.

The tower comprises preferably four corner upright members which may partake of the form of steel angles, as indicated at l, 2, 3 and 4. To

provide necessary rigidity and strength, these angle member are interconnected by diagonals 5 and girts 6. In the preferred form of my invention, the leg members are placed on the corners of a square, as indicated in Fig. 3, and are inclined 5 to the vertical forming a structure having a base larger than its top. At points intermediate the base and top of the tower, there are inserted suitable insulators l, which serve to divide the tower into electrically isolated sections. At the base of the radiating portion of the tower are attached the wires 8 which form the lower part of the active antenna system. These wires or cables come to a point at the ground line and terminate at and are secured to a tension insulator 9. The electri- 6 sulators cal conductors 8 are arranged preferably on the sides of a polygon, as indicated in Fig. 3. Insulators ID are employed to isolate the lower section of the tower from the ground, or the cementitious foundation for the tower.

At or near the top of the radiating portion of the antenna, there are provided radiating supports H, functioning as a spreader frame, from which there are suspended substantially vertical conductors M, the latter being attached at their lower ends to the base of the radiating portion of the tower immediately above the upper set of insulators 1. The conductors M are electrically bonded to the base and top of the radiating portion of the tower and are, therefore, an active part of the antenna. If desired, the wires 8 forming the lower part of the active antenna system may consist of continued extensions of wires I l.

The uppermost set of insulators i should preferably be inserted into the tower legs at a point proportional to one-fourth of the length of the operating wave measured from the top of the tower. This will put them at a point at which the voltage applied to the antenna system is theoretically zero in order to place a minimum electrical strain thereon. On a half wave antenna, therefore, these upper insulators should be inserted at a point half way of the height of the tower. This allows the use of comparatively inexpensive insulators and requires but a minimum of them. The insulators i inserted in the supporting portion of the tower should be preferably not farther apart vertically than one-eighth of the operating wave of the antenna to prevent reradiation. It is to be noted that the antenna described herein may be constructed with the use of materials other than steel without departing from the scope of my invention. Likewise, the in- 1 may be placed at other desired points than those specifically set forth.

The structure describedrequires but a minimum of space to erect a high capacity antenna and is devoid of secondary supporting means such as guy wires and the like, which require additional ground space and add to the cost of the structure. The present antenna is simple to fabricate, erect and maintain and may be produced at a cost materially lower than comparable towers of which I am aware.

What is claimed is:

1. A wave antenna comprising a vertical tower tapering progressively from an enlarged base to a narrow top, means for insulating the base of the tower from the ground, and rigid insulators disposed in said tower intermediate of its length and dividing the latter into an upper active section adapted to act as a radiator of radio waves, and a rigidly related non-radiating base section, said upper active section comprising a metal mast, cross arms at the top thereof, and antenna wires secured to the end portions of the cross arms and descending vertically therefrom in inverted conical order through substantially the extent of said upper active section and said non-radiating base section and secured at their lower ends centrally of the tower base.

2. A rigid wave antenna tower comprising a plurality of upright members interconnected by rigid structural members, said tower being generally of pyramidal form having a broad base portion and tapering to a narrow top portion,

insulators upon which said tower is mounted and electrically isolated from the ground, secondary insulators constituting continuations of said upright members and dividing the tower into an upper active antenna section and a lower inactive supporting section, a ground insulator at the lower end of said inactive supporting section, a spreader frame carried by the top of the tower, conductors extending from said frame and secured to the lower portions of said active antenna section, and a second set of conductors extending from the lower portion of the active antenna section in substantially continuous relationship with respect to said firs mentioned conductors to said ground insulator for connection with a source of electrical energy, said frame including cross arms, and said conductors being secured to the end portions of the cross arms and descending vertically therefrom in inverted conical order.

3. A rigid wave antenna tower comprising a plurality of upright members interconnected by rigid structural members, said tower being generally of pyramidal form having a broad base portion and tapering to a narrow top portion, insulators upon which said tower is mounted and electrically isolated from the ground, secondary insulators constituting continuations of said upright members and dividing the tower into an upper active antenna section and a lower inactive supporting section, a ground insulator at the lower end of said inactive supporting section, a spreader frame carried by the top of the tower, conductors extending from said frame and secured to the lower portions of said active antenna section, and a second set of conductors extending from the lower portion of the active antenna section in substantially continuous relationship with respect to said first-mentioned conductors to said ground insulator for connection with a source of electrical energy, being housed within said tower, said conductors being disposed in inverted conical. order.

4. A wave antenna comprising a vertical tower tapering progressively from an enlarged base to a narrow top and composed of an upper active antenna section and a lower inactive supporting section, an outrigger support carried by the top of the tower, a plurality of spaced conductors having their upper ends secured to said support, said conductors converging downwardly toward the base of the tower in inverted conical order below the upper active antenna section, and an insulator disposed substantially axially of the base of the tower and to which the lower converging ends of said conductors are secured.

5. A wave antenna comprising a vertical tower tapering progressively from an enlarged base to a narrow top and composed of an upper active antenna section and a lower inactive supporting section, an outrigger support carried by the top of the tower, a plurality of spaced conductors having their upper ends secured to said support, said conductors converging downwardly toward the base of the tower inverted conical order below the upper active antenna section, an insulator disposed substantially axially of the base of the tower and to which the lower converging ends of said conductors are secured, and means for supplying electrical energy to be radiated to said conductors.

CHARLES E. SCHULER.

said second set of conductors