US2884631A

US2884631A - Television antennae

Info

Publication number: US2884631A
Application number: US434738A
Authority: US
Inventors: Eugene F O'hare; Adolph M Kline
Original assignee: HARE O
Current assignee: HARE O; O'HARE
Priority date: 1954-06-07
Filing date: 1954-06-07
Publication date: 1959-04-28
Anticipated expiration: 1976-04-28

Description

April 2s, 1959 E. F. o'HARE ET AI.y

TELEVISION ANTENNAE Filed June 7,. 1954 x m s M .a n El a FIG-4 FIG-5 y INVENTOR` Eugene /'arer c/o//S/VK//fle ATTORNEY FIG-2 United States Patent TELEVISION ANT ENNAE Eugene F. OHare and Adolph MQKline, University City, Mo.; said Kline assignor to said OHare Applicationvlune 7, 1954, Serial No. 434,738 4 Claims. (Cl. 343`8'17) This invention relates in general to certain new and useful improvements in television antennae `and, more particularly, to an indoor antenna capable of receiving ultra high frequency signals.

Television broadcasting presently employs very high frequency and ultra high frequency wave `bands which are respectively referred to as VHF and UHF. Television sets of very recent design have 'tuners and other electronic components built in for receiving both wave bands and older types of television sets which were originally designed to receive only VHFsign'alscan be adapted for UHF reception by the use of so-called converters. In either instance, however, vitfis necessary to use one type of antenna for the reception of VHF signals and an entirely different type of antenna for receiving UHF signals. Originally, it was 'thought that a UHF antenna necessarily had to be located on the outside of the house or building in which the Ireceiving set was located. However, it is very costly and frequently impossible for people living in large metropolitan apartment houses, hotels, and the like, to employ outside aerials. Therefore, many people have not been able to convert to UHF.

lt is, therefore, the primary object of the present invention to provide a UHF antenna of the indoor type.

It is a further object of the present invention to provide an indoor UHF antenna which is not only simple in construction and economical in cost, but also has an unusually high gain and, therefore, produces a clear, distinct and powerful signal in the television set with which it is connected.

It is also an object of the present invention to provide an indoor UHF antenna which is attractive in appearance, compact in size, and can be readily shifted to any desired angle for the purpose of receiving a selected UHF signal with maximum efficiency.

It is a further and most important object of the present invention to provide a UHF antenna having a relatively broad band of frequency response with a relatively high reception efficiency which is substantially uniform throughout the entire breadth of the frequency band.

With the above and other objects in View, our invention resides in the novel features of form, construction, arrangement, and combination of parts presently described and pointed out in the claims.

In the accompanying drawings- Figure 1 is a perspective view of a UHF antenna constructed in accordance with and embodying the present invention;

Figure 2 is a side elevational view of the antenna;

Figure 3 is a front elevational view of the antenna; and

Figures 4- and 5 are fragmentary transverse sectional views taken along lines 4 4 and 5 5, respectively, of Figure 3.

Referring now in more detail and by reference characters io the drawings, which illustrate a preferred embodiment of the present invention, A designates a UHF antenna comprising a preferably rectilinear back panel or reflector 1 formed of a plane surfaced preferably perforated metallic sheet. The shape or configuration Aof the perforations is of no particular significance in the present invention, but it has been found essential for maximum eiciency that the forwardly presented face or reflective surface F of the reflector 1 be smooth and planar in character. Welded, riveted, or otherwise rigidly secured in vertically aligned parallel relationship centrally of the face F of the reliector 1, and projecting horizontally outwardly therefrom, are two similarly shaped brackets 2, 2', integrally provided at their outer ends with vertically aligned attachment ears 3, 3', respectively. Riveted to and extending equidistantly on either side of the ears 3 is a rectangular mounting block 4 formed of electrically non-conductive material and `provided upon its outer ends with laterally extending similarly shaped

metallic wings

5, 6, having straight diverging top and bottom edges and inwardly and rearwardly concave outer margins.

As will be noted `by reference to Figures 4 and 5, the

wings

5, 6, are actually curved to conform to a cylindrical section so that all horizontal lines are parallel to the central axis of symmetry. In other words, any vertical section will conform toa circular arc.

Similarly welded to the 'ear 3' is amounting block 4 provided with wingsl 5', 6', respectively, all of which are substantially identical in shape 'and structure to the mounting block 4 and

wings

5, 6. As 'will be seen by `reference to Figure 3,`the

wings

5, 5', 6, 6', are of such size and are so positioned that they will lie entirely within the peripheral contours of the reflector 1.

Mounted between the blocks 4, 4', are spaced Vparallel metal tubes 7, S, which are lattened at their upper and lower ends for electrically 'contactive engagement to the

wings

5, and 6, 6', respectively. The

tubes

7, 8, are furthermore electrically connected approximately at their midpoints to a coaxial lead-in wire 9.

Suitably fastened to the bracket 2 is a depending rod it? which is, in turn, mounted at its lower end in a suitable rectilinear flat bottomed base 11, which is adapted to rest upon a table top or any other flat surface and support the antenna A in upright position thereon.

Television antennae constructed in accordance with the present invention have been found to possess uusually high gain characteristics and consequently such an antenna can be used indoors. lt is thought that this unique characteristic can be attributed to the fractional wave spacing symmetry resulting from the employment of a iiat, truly plane surfaced reflector and an element disposed in front thereof, which element is a substantially triangular segment of either a cylinder or a cone. Obviously the perpendicular distance from the reflector surface to the wings will vary from a minimum distance at the center of the wings to a maximum distance out at the tips of the wings. Consequently, the antenna of the present invention will be capable of maintaining a standing wave for all frequencies, the nodes-length of which fall Within these dimensional limits. As shown in Figure 2, the distance d falls within the range of .2L to .3L and the distance d' falls within the range .2L' to 3L', L and L respectively representing the minimum and maximum wave lengths of the wave length range or band for which the antenna is designed. At the present time, all conventional U-lF antennae are substantiaily specific for a single frequency, or at best a very narrow band of frequencies around such single frequency. As a result, the eflciency of such conventional antennae and the receiving sets with which they are associated drops off sharply for all wave lengths or frequencies outside of the particular frequency for which such antenna is dimensionally designed.

It has also been found in connection with the present invention that, by arranging the diverging longitudinal margins of the wings in such a manner that they are non-parallel to the planar surface of the reflector 1, the impedance characteristics inV relation to signal gain are markedly improved. It will, of course, be understood that antennae constructed in accordance with the present invention, like all reflector-type antennae, are highly directional, but antennae embodying the present invention can very simply and conveniently be manually oriented without resort to expensive motor driven turning equipment or other complicated gear. It will also be understood that the present invention is not limited to the particular array shown in the drawings consisting of two vertically spaced pairs of identically shaped oppositely extending Wings, but may, where desired, be modified to include one or more such pairs of wings.

It should be understood that changes and modications in the form, construction, arrangement, and combination of the several parts of the television antenna may be made and substituted for those herein shown `and described without departing from the nature and principle of our invention.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

1. A UHF antenna consisting of a reector having a forwardly presented planar Surface, means for supporting said reflector with its planar surface in substantially vertical position, and radiation receiving elements rigidly mounted in front of, and in outwardly spaced relation to, said reector, said elements being substantially in the form of a triangular segment of a cylinder.

2. A UHF antenna consisting of a reflector having a 'forwardly presented planar surface, means for support ing said reector with its planar surface in substantially vertical position, and radiation receiving elements rigidly mounted in front of, and in outwardly spaced relation to, said reflector, said elements being substantially in the form of arcuate segments of a cylinder and being curved outwardly with respect to said surface.

3. A UHF antenna consisting of a retiector having a forwardly presented planar surface, means for supporting said reector with its planar surface in substantially vertical position, and a plurality of vertically spaced pairs of laterally aligned radiation receiving elements rigidly mounted in front of said reector, each of said elements being curved arcuately outwardly with respect to said planar surface and having the shape of a segment of a cylinder.

4. A UHF antenna consisting of a reector having a forwardly presented planar surface, means for supporting said reflector in substantially vertical position, and a pair of vertically spaced radiation receptors rigidly mounted in front of, and in outwardly spaced relation to the reector, said receptors each including two axially aligned wings each being substantially in the form of a triangular segment of a cylinder and having longitudinal edges which diverge outwardly from both the horizontal and vertical center-lines of the receptor, said longitudinal edges being non-parallel to said planar surface, said wings being convex with respect to the reector, the distance from said surface to the wings being within the range of 0.2L to 0.3L and the distance from said surface to said longitudinal edges being within the range of 0.2L to 0.3L where L and L' represent the minimum and maximum wave lengths, respectively, for which the antenna is designed.

References Cited in the le of this patent UNITED STATES PATENTS 2,163,770 Von Radinger June 27, 1939 y 2,237,778 Carter Apr. 8, 1941 FOREIGN PATENTS 439,608 Great Britain Dec. 10, 1935 OTHER REFERENCES Electronics, page 34, January 1952. Radio Electronics, page 25, December 1952.