US 2666138 A
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Jan. 12, 1954 E. J, EHRBAR ETAL ANTENNA Filed May 25, 195o mnmmmmilL ...will
INVENTORS. E :AWARD d. EHRBAR By RAYMO N D W` CRO'NSHEY www ATTO RNEY,
Patented Jan. 12, 1954 UNITED STATES PATENT oFFlcE ANTENNA Edward J. Ehrbar and Raymond W. Cronshey,
Cleveland, Ohio, assignors to The Radiart Corporation, Cleveland, Ohio, a corporation of Ohio Application May 25, 1950, Serial No. 164,101
(Cl. Z50-33) 7 Claims. l This invention relates, as indicated, to an antenna, but has reference more particularly to an improved indoor antenna, which is particularly adapted for use in connection with television sets.
A primary object of the invention is to provide an antenna of the character described, which is of simple, sturdy construction, and is so designed as to be broadly resonant to all present broadcasting channels.
Another object of the invention is to provide an antenna of the character described, comprising two sets of dipoles, one of which is so designed as to be in resonance electrically with television broadcasting stations in the present high band television allocation or spectrum, and the other of which comprises elements of a combination which is in resonance electrically with television broadcasting stations in the present low band television allocation or spectrum.
A further object of the invention is to provide an antenna of the character described, consisting of two sets of dipoles, one of which is mechanically as well as capacitatively coupled with the other.
A still further object of the invention is to provide an antenna of the character described, which is highly efficient in use, and Well adapted for indoor use, producing a signal strength which yis superior to those of other indoor antenna conventionally used for television purposes.
Other objects and advantages of the invention will be apparent during the course of the following description.
In the accompanying drawings, forming a part of this specification, and in which like numerals are employed to designate like parts throughout the same.
Fig. 1 is a front elevational view of an antenna, iembodying the principal features of the invenion;
Fig. 2 is a fragmentary View, of the central portion of the antenna, with the front cover plate ordisc removed, and taken on the line 2--2 of Fig. 3;
Fig. 3 is a cross-sectional View, taken on the line 3-3 of Fig. 2, and
Fig. 4 is a fragmentary cross-sectionalview, ,taken` on the line 4-4 of Fig. l.
Referring more particularly to the drawings, the antenna will be seen to comprise a base I. molded from a plastic material, such, for example, as Bakelite, and having threadedly secured thereto a mast 2 formed of metallic tubing, preferably aluminum tubing.
at full size scale,
Mounted on the upper end of the mast 2 is a circular antenna support, consisting of a front plate or disc 3 and a rear plate or disc 4, the discs 3 and 4 being molded from a plastic insulating material, such as Bakelite, and being removably secured to each other, as by a screw 5 passing through a central aperture 6 in the rear plate and into a threaded axial recess 8 in the front plate. The plates 3 and 4 are molded to provide radial recesses 9, of semi-circular corss-section, which coact to receive and snugly engage the upper end portion oi the mast 2.
The plates 3 and 4 are also molded to provide downwardly extending divergent recesses I0 of 'I semi-circular cross-section, which coact to receive and snugly engage the inner ends of aluminum tubes II and I 2 which form elements of a dipole, which are so dimensioned as to be in resonance electrically with television broadcasting stations in the present righ band television allocation or spectrum, such, for example, as channels 7 to 13, inclusive The plates 3 and 4 are also molded to provide upwardly extending divergent recesses I3 of semi-circular cross-section, which coact to receive and snugly engage the inner ends of aluminum tubes I4 and I5, which form elements of a second dipole. The inner ends of the tubes I4 and I5 are spaced from each other, and the recesses I3 are in communication with each other, forming a space between the tubes I4 and I5, in which a coil i5 is disposed. The coil I (i is an inductance coil, preferably formed of fine enameled Wire, wound around a core I'I such as Bakelite, or other suitable material, the ends I8 of the coil being clamped to the tubes I4 and I5 by the heads of self-tapping screws I9 which are threaded into the tubes.
The coil I6 has an inductance, which permits the combination of the dipole elements I4 and I5 and the coil I5 to be in resonance electrically with television broadcasting stations in the present low band television allocation or spectrum, such, for example, as channels 2 to 6, inelusive.
The dipole elements II and I2 are bent upwardly at their outer ends, and the dipole elements I 4 and I5 are similarly bent downwardly at their outer end-s extending downwardly to points spaced from the outer ends of the elements I I and l2. Buttons 2li, formed of a plastic insulating material are employed as means for mechanically joining the dipole elements II and I2 to the dipole elements I4 and I5 at their ends. From an electrical standpoint, the buttons 20 tion of these is capacitatively coupled to the dipole II-I2 at their ends. While the entire antenna might be considered as'. a combination of inductive and capacitative coupling, the major coupling is capacitative.
Although the use of aluminum tubing has been referred to, it will be understood that brass tubing or other tubing of a conductive material may be employed.
The terminals or contacts 2| and 22 of a transmission line 2.3 are secured electrically to the tubes II and I2, as by clamping4 such contacts to the plate 4 by means of the heads of self-tapping screws 24 which extend through the plate 4 and into threaded engagement with the tubes I I and I2. The transmission line 23 is a conventional one employed to connect the antenna to the television set or receiver.
While the lower dipole elements are shown as in divergent relation to the upper dipole elements, it will be understood that they can also be paralel with each other.
An antenna, as` thus constructed, has` been found highly efcientin use, and well adapted for indoor use, producing a signal strength which is'superior tothose offother indoor antenna conventionallyr used for'television purposes.
rLihe partsare. easy tomanufactureand assemble, and the constructionY is relatively inexpensive, and well adaptedv for mass production.
It is to be understood that the form of our invention, herewith shown and described, is to be taken as a preferred example of the same, and that Various changes in the shape, size. and arrangement of parts maybe resorted to, without departing from Vthe spirit of'our invention or the scope of the subjoined claims.
Having thus described our invention we claim:
1. An antennafor television purposes and the like, comprising a4 base, a mast, a pair'of connected discs of insulating material mounted on said mast and disposed with their axes in a substantially horizontal plane, a pair of dipole elements mounted in said discs with their inner ends in spaced relation from each other, a second pair of dipole elementsmounted in said discsA above said first-named pair, and with their inner ends in spaced relation from each other, and an inductance coil disposed within said discs, in the space between said second pair of dipole elements,
.and having its ends connected to said second pair or dipole elements.
2. An antenna, as defined in claim 1, in which said first pair of dipole elements have upturned outer ends, and said second pair of dipole elements have downturned outer ends in spaced relation to the upturned ends of the rst elements, and buttons of insulating material are disposed in the spaces between said outer ends `and. are mechanically connectedV to said outer ends.
3. An antenna for television purposes-and the like, comprising a base, a mast supported by said base, a pair of substantially flat discs of insulating material mounted on said mast and disposed with their axes in a substantially horizontal plane, screw means interconnecting said discs and clamping said discs to said mast, a pair of divergent dipole elements mounted in said discs with their inner ends in spaced relation to each other, a second pair of divergentdipole'elements mounted in said discs above said first-named pair, and with their inner ends in spaced relation from cach other, and an inductance coil disposed within said discs in the space between said second pair of dipole elements, and having its ends con- :nected to the inner ends of said second pair of dipole elements, said first pair o1" dipole elements having upturned outer ends, and said second pair of dipole elements having downturned ends in spaced relation to the upturned ends of the nrst elements, buttons of insulating material disposed in the spaces between said outer ends and'mechanically connected to said outer ends, a trans,y mission line having terminals, and'means'electri# cally connecting said terminals to: the innerends of said first pair of dipole elements.
4. An antenna, as dened in claim 3J; in which said means comprises screws extending: through one of said discs and tothe inner ends of' said rst pair of dipole elements, the headsofsad screws clamping said terminals to. said disc.:
5. An antenna for television purposes iandthe like, comprising a dipole comprising spaced-rods like elements having upturned ends, and a second dipole comprisingfspaced rod-like elements hay; ing down-turned ends in spaced relation to the upturned ends of the rst elements, buttonseof insulating material disposed in the spaces be'- tween said ends and mechanically vconnectedftc said ends, and an inductance coil connecting-the elements of the second dipole.V
6. An antenna, as defined in clairn, inrwhich the elements of the rst dipole extend downwardly from the space between them and diverge from each other, and the elements of the second-dl!- pole extend upwardly from the space between them vandfdiverge from each other.
7. Anv antenna, of the character described, com'- prising a base, a mast, a pair of connected'discs of insulating material mountedon saidimast, diipole elements in spaced relation' to each other mounted in said discs, and other dipole elements mounted in said discs Aand capacitatively coupled to said rst-named elements, said second' dipole elements being connected by an inductance coil disposed within said discs.
EDW' ARD J. EHRBAR'. RAYMOND W. CRONSHEY-` References Cited in the file of thispatent z UNITED STATES PATENTS Number Name Date'v 1,740,851 Franklin Dec. 24, 1929 2,289,856 Alford July 14, 179,42 2,311,472 Roosenstein Feb. 16, 1943 2,447,879 Scheldorf Aug. 24,. 1948 2,495,579 Ferris Jan, 24,1950 2,505,115 Hills et al. Ap1. 251950 2,532,094 Gonsett etal. ---.Now 28,1950 2,563,243 Hills Aug.. 7,v 1951 2,578,973 Hills Dec.Y 18,V 1951