US3725944A

US3725944A - Free standing fiberglass antenna

Info

Publication number: US3725944A
Application number: US00109825A
Authority: US
Inventors: M Valeriote
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-01-26
Filing date: 1971-01-26
Publication date: 1973-04-03
Anticipated expiration: 1990-04-03

Abstract

An antenna which is constructed exclusively of fiberglass, with the sole exception of the electrical conductors, couplings, and upper and lower ends, which may incorporate fiberglass or some other material, which antenna is constructed in a series of lengths, or in a single length in the case of a very short antenna, each of the lengths being essentially of hollow tubular construction, with the walls of the tube made up of alternate layers of glass fiber filaments, one such layer being made up of filaments extending longitudinally along the axis of the antenna, and the next such layer being made up of filaments which are wound spirally around the antenna, anywhere from four to twelve or more such layers being employed one upon the other, and in which the antenna base is constructed with at least the longitudinal glass fibers being formed into a generally bellshaped base member, and incorporating a reinforcing core of which may be fiberglass or some other material with such longitudinal fibers extending through a central opening in the core, and then being folded backwardly around the exterior of the core, and led alongside the exterior of the antenna itself for a predetermined distance, the exterior of the core and fiberglass filaments extending therearound, being formed into a suitable base shape, by means of an exterior mould which is clamped therearound under pressure during curing of the resin.

Description

United States Patent 1 Valeriote, Jr.

[54] FREE STANDING FIBERGLASS ANTENNA [76] Inventor: Michael Archibald Valeriote, Jr.,

R.R. No. l Puslinch, Guelph, Ontario, Canada 22 Filed: Jan.26, 1971 21 Appl.No.: 109,825

1 [52] US. Cl. ..343/873, 343/895, 343/900 [51] Int. Cl. ..H0lq 1/40 [58] Field of Search ..343/7l5, 873, 900, 912, 895' [56] References Cited UNITED STATES PATENTS 3,198,878 8/l965 Kaczercinski ..264/l37 3,102,268 8/1963 Foley ..343/895 2,763,003 9/1956 Harris... ..343/873 FOREIGN PATENTS OR APPLICATIONS 801,200 9/1958 Great Britain ..343/900 Primary Examiner-Eli Lieberman Att0rneyGe0rge A Rolston [11] 3,725,944 [451 Apr. 3, 1973 [57] ABSTRACT An antenna which is constructed exclusively of fiberglass, with the sole exception of the electrical conductors, couplings, and upper and lower ends, which may incorporate fiberglass or some other material, which antenna is constructed in a series of lengths, or in a single length in the case of a very short antenna, each of the lengths being essentially of hollow tubular construction, with the walls of the tube made up of alternate layers of glass fiber filaments, onesuch layer being made up of filaments extending longitudinally along the axis of the antenna, and the next such layer being made up of filaments which are wound spirally around the antenna, anywhere from four to twelve or more such layers being employed one upon the other, and in which the antenna base is constructed with at least the longitudinal glass fibers being formed into a generally bell-shaped base member, and incorporating a reinforcing core of which may be fiberglass or some other material with such longitudinal fibers extending through a central opening in the core, and then being folded backwardly around the exterior of the core, and led alongside the exterior of the antenna itself for a predetermined distance, the exterior of the core and fiberglass filaments extending therearound, being formed into a suitable base shape, by means of an exterior mould which is clamped therearound under pressure during curing of the resin.

9 Claims, 7 Drawing Figures PATEIHEUAPRS m5 sum 1 or 3 Inventor MICHAEL A. VALERIOTE JR.

PATEHTEUAFM ms snmanrs In ventor MICHAEL A VALERIOTE UR.

PATEIHWPM ms 7 5,944

SHEETBUFS Inventor MICHAEL A. VALERIOTE JR.

y: gage 7% FIG.6

STANDING FIBERGLASS ANTENNA The present invention relates to a free standing antenna, that is to say an antenna that may be erected and supported on a base on one end of the antenna, without the use of guy wires or other supporting devices.

BACKGROUND OF THE INVENTION It is frequently desirable to employ an antenna of substantial length, which may be erected vertically, and simply stands upon a base without any attachment wires or other supporting means. Antennae of this kind are used when it is desired to transmit or receive signals which are tuned to the length of the antenna, and it is well known that the use of guy wires or other supporting means in. such a casesubstantially interfers with the quality of reproduction.

Antennae of this type are frequently used in exposed locations, such as on the deck of navel vessels and the like where they are frequently subjected'to winds of hurricane strength.

In the past, such antennae have usually been fabricated of metal, such as aluminum or aluminum alloys, and it has proved impractical to construct such metal antennae, which will withstand extreme stresses from wind or the like. It has of course been well known for many years that fiberglass, construction will withstand considerably greater stresses of this kind than metal, but it has not hitherto proved practical to construct fiberglass antennae which would out perform metal antennae, notwithstanding the known suitability of fiberglass construction for the purpose. Certain antennae are made which employ fiberglass construction in some way, usually combined with some form of metal construction, with some success. One of the problems associatedwith such earlier efforts has been the difficulty of achieving a suitable bond between the fiberglass and the metal, which was sometimes in the form of sleeves and flanges, and in some cases, difficulty has been experienced in the most effective utilization of the glass fiber filaments themselves. Another problem that has proved extremely troublesome in the past, has been-the construction of a base suitable for mounting the antenna, and supporting it under all operational stresses. Generally speaking, where the base incorporated any metal, then the metal and the fiberglass tended to separate under extreme stresses, and where the base was made of pure fiberglass construction, it generally speaking proved to be inadequate.

BRIEF SUMMARY OF INVENTION The invention therefore seeks to overcome these various disadvantages, by the provision of an antenna which is constructed exclusively of fiberglass, with the sole exception of the electrical conductors, and in certain cases, the base itself, which may incorporate a core of fiberglass or some other material, which antenna is constructed in a series of lengths, or in a single length in the case of a very short antenna, each of the lengths being essentially of hollow tubular construction, with the walls of the tube made up of alternate layers of glass fiber filaments, one such layer being made up of filaments extending longitudinally along the axis of the antenna, and the next such layer being made up of filaments which are wound spirally around the antenna,

preferably four and in some cases six such layers being employed one upon the other, and in which the. antenna base is constructed with at .least the longitudinal glass fibers being formed into a generally bell-shaped base member, and incorporating a reinforcing core of which may be fiberglass or some other synthetic with such longitudinal fibers extending through a central opening in the core, and then being folded backwardly around the exterior of the core, and led alongside the exterior of the antenna itself for a predetermined distance, the exterior of the core and fiberglass filaments extending therearound, being formed into. a suitable base shape, by means of an exterior mould which is clamped therearound under pressure during 1 curing of the resin.

Further and other related objects and advantages of the invention will become apparent from the following description of a preferred embodiment of the invention which is given here by way of example only, with reference to the following drawings, in which like reference devices refer to like parts thereof throughout the various views and diagrams and in which.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective illustration of a base length of antenna according to the invention, partially cut away to reveal its construction;

FIG. 2 is a section along the line 2-2 of FIG. 1;

FIG. 3 is a sectional detail of the jointing mechanism provided between two adjacent lengths of antenna along the line 33 of FIG. 1;

FIG. 4 is a schematic illustration showing the formation of the antenna according to the invention on a suitable winding mandrel mechanism;

FIG. 5 is a greatly enlarged side elevational view of one end of the winding assembly as shown in FIG. 4, at a later stage in the construction, during construction of the baseof the antenna;

FIG. 6 is a cut away perspective of part of the antenna base, and

FIG. 7 is a sectional view of the construction of the top end of the antenna.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, it will be seen that these Figures illustrate a base or lower section of the preferred embodiment of. the invention, it being understood that a complete antenna according to the invention may comprise simply a single section, or two or possibly three or more such sections joined together.

As shown in FIG. 1, the antenna consists of a tubular main body portion 10, and a base portion 11, which are formed integrally with one another, and designed to withstand predetermined loads, as an integral onepiece unit.

As shown in FIGS. 1 and 2, the main tubular body portion 10 will be seen to consist of alternate layers,

comprising an innermost layer 12, a first intermediate layer 13, a second intermediate layer 14, a third intermediate layer 15, and an outermost layer 16. It will be understood that there may be more or less such layers depending upon the design requirements of the particular antenna. The innermost layer 12 will be seen to be formed of a length of fiberglass filament material referenced as 12, wound continuously on itself in a helical or spiral manner. The first intermediate layer 13 will be seen to be comprised of a continuous length of glass filament material. referenced as 13, which filament material is run longitudinally from end to end along the length of the main body portion 10, at least, and preferably through and around the base 11 in a manner to be described below. The material'l3', in fact consists of a continuous length of glass filament material run from end to end of the antenna 10, being formed into loops at each end as described below. The second intermediate layer 14 comprises a continuous length of glass filament material 14, wound in a helical or spiral manner around the first intermediate layer 13, in essentially the same manner as the innermost layer 12. The third intermediate layer 15, will be seen to comprise a continuous length of glass filament material 15, which is arranged longitudinally, in the same manner as the glass filament material 13' in the layer 13, running from end to end of the length of the main body portion 10, being formed into loops at each end thereof.

The outermost layer 16, will be seen to comprise a continuous length of glass filament material 16', wound in a helical or spiral manner about the intermediate layer 15, in the same manner as described above in association with the second intermediate layer 14.

Clearly, to those experienced in the fiberglass forming art, it will be apparent that by this arrangement, the continuous helical or spiral wound layers l2, l4 and 16 provide a maximum hoop stress characteristic, resisting deformation of the cylindrical tubular shape of the antenna 10, when the same is bent under extreme stresses, while the longitudinal filaments 13', 15' in the

intermediate layers

13 and 15 provide maximum lengthwise stress resistance preventing any tendency for separation to take place between individual helical or spiral winding of the

layers

12, 14, and 16, when the same are subjected to excessive bending stresses.

Referring now to the base 11, it will be seen that this is formed around a core referenced as 20. The core 20 may be formed of any suitable material such as fiberglass, or polyurethane foam plastic material formedv into a generally frusto-conical shape with a hollow interior, and a flattened flange 21. Obviously, the core 20 could be formed of other material such as wood, or the like, the particular material selected for the purpose of being one which is readily formed into a desired shape, and is adapted to withstand compressive stresses, when suitably mounted as in the present invention.

With further reference to the core 20, it will be seen that this is provided with a hollow central axial opening 22, and that the

respective layers

12, 13, 14 and 15 are led through such central opening 22, and is bonded to the interior surfaces thereof. It will be further noted that the

layers

13 and 15 comprising the longitudinally extending strands or filaments of glass fiber material, extend right through the central opening 22, and are then led around the flattened lower portion of the core 20, to form

layers

13a and 15a, and are then folded around the flange portion 21, and alongside the conical exterior thereof, and extend partially upwardly alongside the cylindrical portion of the antenna 10, being overlapped within the outermost helical layer 1.6, at the enlarged neck portion 23. It will be appreciated that the interior of the cylindrical antenna 10, is supported on a cylindrical mandrel in known manner during manufacture, thereby providing a rigid interior support therefore, and the

layers

13a and 15a of the filaments v extending around the core 20, are formed into a predetermined exterior shape by means of a two-part shell mould (not shown) adapted to be clamped therearound to form the same into the desired shape.

It will of course be understood that the number of layers of

longitudinal filaments

13, 15 etc. that may be folded around the exterior of the core 20 may be varied depending upon the total number of such longitudinal layers in the cylindrical portion 10 of the antenna. in some cases, there may be five or six longitudinal layers, and five or six helically wound layers, in which case there will be five or six such longitudinal layers which are folded'around the core 20, and overlapped upwardly alongside the antenna 10 as shown. In any event, the particular objective achieved by this form of construction is to ensure that the entire base structure 11 is formed together with the antenna 10, at a single homogeneous unit with the longitudinal stress resistance incorporated in the base 11, being of the very highest order, so as to withstand all stresses which can be withstood by the antenna 10 as a whole.

As noted above, the particular antenna segment or section illustrated in FIGS. 1 and 2, may comprise the entire antenna, or may be merely the base or lower section of a two or three part antenna. In the case of a multi part antenna, the joints are formed of screw threaded joints somewhat in the manner of a fishing rod. A section through a typical joint is shown in FIG. 3. In this illustration, it will be seen that the upper end of the lowermost antenna segment 10 shown at the left hand side of the drawing, and the lower end of the next adjacent antenna length referenced as 24 is shown at the right hand side of the drawing. The connection means between the two antenna lengths will be seen to comprise the male and

female ferrule members

25 and 26, attached respectively to the upper end of the lower section 10, and the lower end of the upper section 24 as shown. The upper end of the lower section 10 is formed with a inwardly tapered shoulder 27, and one or two of the outermost layers of material, in this case shown for example as 15 and 16, are cut away so as to define a square abutting surface 28. The male threaded ferrule 25 has a hollow generally cylindrical interior, as shown, and preferably the majority of the layers, in this

case

12, 13, and 14, are led into the interior of the ferrule 25, and bonded thereto. Preferably a layer of suitable filling material such as epoxy resin or the like referenced as 29 is provided between the edge of the ferrule 25, and the shoulder 27 to provide a smooth exticular bending characteristics for a particular purpose,

but in this particular case, it is thought to make for clarity if the same number of layers is shown throughout. It will thus be seen that the female threaded ferrule 26 has a base rim 30, and a smooth generally cylindrical exterior surface. The layers 12 to 16 inclusive are preferably wound in such a manner that they fit snugly around and are bonded to the exterior of the ferrule 26, and provide a cylindrical tubular extension generally indicated as 32, fitting snugly around the exterior of the epoxy resin filler material 29, and preferably defining a lower abutting surface 33, adapted to abut with the abutting surface 28 of the antenna section 10. Preferably, the main portion of the antenna section 24 will be of somewhat reduced diameter in relation to the sleeve portion 32, to provide a Embedded within the layers of the antenna, are a plurality of electrically conductive metallic strips 34' being preferably laid in longitudinal arrangement between the first layer 12 and the next adjacent layer 13. In the region of the base 11, such conductors 34 are brazed or otherwise electrically connected to a connector ring member 35, and a suitable connection member indicated as 36 will extend through thewall of the antenna 10, or any other suitable electrical connection means may be provided to suit their particular circumstances.

In the region of the male ferrule 25, at the upper 'end of the section 10,'the metallic strips 34, are brazed as at 37, to the ferrule 25.

In the next adjacent antenna section 24, similar metallic strips 34 are provided in essentially the same location, and they are laid alongside the cylindrical exterior of the female ferrule 26, and brazed thereto. Electrical connection is thus made through the ferrules 2S and 26, to provide for a continuous electrical connection throughout the length of the antenna.

Preferably, according to the invention the metallic strips 34 are not arranged along the longitudinal axis of the antenna, but form a single rotation therearound along any one length of the antenna, in the form of a slow spiral. In the way, sufficient extra length of the metallic strips 34 is provided to ensure that even when the antenna is bent into a 180 arc, the strips 34 do not tend to become separated from the layers of fiberglass material, or rupture the same.

Preferably, as stated, the antennae according to the invention is formed by means of the mechanism as shown in FIGS. 4'and 5. In these illustrations, it will be seen that a mandrel 40, is rotatably mounted on bearings 41, and may be rotated by means of an electrical motor 42. The fiberglass filament material is indicated as 43, and is stored on a spool 44. Preferably, the filament material 43 passes through a bath 45, containing liquid resin material, before it is wound on the mandrel 40.

As stated above, alternate layers of the antenna 10, and upper antenna portion 24, are formed by means of lengthwise or longitudinally extending portions of fiberglass filament material, and these are preferably supported and arranged on the mandrel by means of the

collar members

46 and 47, provided with outwardly extending books 48, around which the longitudinal strands of filament material 43 may be strung from end to end along the mandrel. 40.

Preferably, the mandrel 40 is provided with a very slight taper from end to end so as to provide a tapering construction for the antenna as it is constructed thereon.

Referring more particularly to FIG. 5, it will be seen that this drawing illustrates the formation of the base 11 of the antenna 10. According to the invention, the core 20 is built into the antenna. 10, during construction, for maximum strength. In order to achieve this, the helical windings of filament material 43, forming the respective helically wound layers 12, 14 and 16 are preferably terminated somewhat short of the collar 47 at the larger end of the mandrel 40, leaving the end portions of the longitudinal strands of filament material 43 exposed. It will be understood from FIG. 4 that the strands of longitudinal material forming any one such layer are continuous, and form loops around the hook members 48 at each end. In order to provide a sufficient length of the lengthwise filaments, to fold over the outside of the core 20, the respective loops of filament material 43, at the larger end of the mandrel 40, are released from the hooks 48, by cutting alternate strands thereby, leaving loose ends 50 which are approximately twice the length of each of the loops. The collar 47 is then removed, and the core member 20 is slipped around the loose ends 50 of filament material, and is slid onto the mandrel, around the helically wound strands of filament material 43, into approximately the position as shown in FIG. 5. The loose ends 50 are then folded around the exterior of the core 20, and led alongside the helically wound strands, and are then bonded thereto by a winding on a further layer of helically wound strands over such loose ends.

As mentioned above, the exterior shaping of the entire base 11 is then achieved by compressing the exterior of the base 11 by means of an outer shell mould (not shown) consisting of two half shells, defining a suitable exterior shape of the base 11, which are clamped tightly around the core 20, and filament lengthextending therearound, thereby compnessing the same-into a single homogenous unit, having great strength, and at the same time having auniform exterior appearance.

Preferably, after removal of the antenna 10, from the mandrel 40, the lower and upper ends are sealed by means of lower and

upper plug members

51 and 52.

The upper end of the antenna is preferably finished off by means of a solid brass: plug member 52 of generally hemispherical shape, having a hollow cylindrical stem member 53 adapted to extend into the upper end of the antenna, and the conductorstrips 34 are preferably led up into theinterior of the cylindrical stem 53, and fastened therein by solder or the like.

The foregoing is a description of a preferred embodiment which is given here by way of example only. The

invention is not to be taken as limited to any of the specific features as described, but comprehends all such variations thereof as come within the scope of the appended claims.

What I claim is:

l. A free standing antenna device having a main body portion formed of one or more body sections, a base end and a free end, and adapted to be fastened in position at its base end only the remainder thereof being free of support and comprising;

a hollow tubular main body portion having upper and lower ends and formed of a plurality of layers of glass fiber material, certain of said layers comprising helically wound glass fiber filaments and altemate said layers being longitudinally extending strands of said glass fiber filaments, said filaments being integrally bonded together;

a base end portion on said lower end of said main body having an exterior profile of generally bellshaped configuration with a flattened end surface, said base end having a generally collar-like core member of non-conductive material formed with a generally flattened antenna support surface at one end thereof, and said core member defining a generally cylindrical opening extending axially therethrough and through said support surface, said opening permitting said core member to fit snugly over said main body portion at said lower end thereof; at least some of said longitudinally extending strands of filaments forming an integral part of said base end portion and extending around the exterior of said core member;

a closed end on said upper end of said main body portion, and,

electrically conductive means extending substantially along the length of said main body portion.

2. A free standing antenna device as claimed in claim 1 including endwise extensions of some of said longitudinally extending strands of said glass fiber filaments extending through said cylindrical opening of said core member, said endwise filament extensions being folded around the exterior of said support surface and said core member and back up alongside a portion of said main body portion and bonded thereto and to said core member whereby to secure said core member integrally with said base end of said main body portion.

3. A free standing antenna device as claimed in claim 1 wherein said main body portion comprises upper and lower body sections separable from one another for shipping and storage, and when assembled together, forming said main body portion.

4. A free standing antenna device as claimed in claim 3 wherein said lower body section'has lower and upper ends,'said lower end comprising said base end of said main body portion, and including coupling means on said upper end of said lower body section, and wherein said upper body section defines lower and upper ends,

said upper section upperend defining said upper closed end of said main body portion, and coupling means on said upper section lower end for interengagement with said coupling means on said upper end of said lower body sections.

5. A free standing antenna device as claimed in claim 4 wherein said coupling means comprise a male exterior threaded coupling member on one said end, and a female interior threaded coupling member on the other said end.

- 6. A free standing antenna device as claimed in claim 4 including electrically conductive means extending along the length of each of said upper and lower body sections, said conductive means terminating at said coupling means, and including contact ring means incor orate d in said coupling means, electrically connec ed with said electricaly conductive means, and

adapted to interengage with one another and make electrical connection through said coupling when said coupling means are interengaged with one another.

7. A free standing antenna device as claimed in claim 4 including at least one intermediate body section between said upper and lower body section, and coupling means at each end of said intermediate body section for interengagement with adjacent coupling means on adjacent said upper and lower body sections.

8. A free standing antenna device as claimed in claim 1 wherein said electrically conductive means comprise a plurality of separate electrical electrically conductive strips, said strips being embedded within said integrally bonded filament of said main body portion, along the major portion of their length, said electrically conductive strips being arranged in an extended spiral manner whereby to define at least a partial rotation relative to the axis of said main body portion.

9. A free standing antenna device as claimed in claim 1, wherein said longitudinally extending filament at least comprise a continuous strand of said filament, said strand being arranged to run from one end to the other of said main body portion along the length thereof and being formed into a loop at each end thereof, at least some of said strands of longitudinal filaments, at said base end of said main body being cut so as to permit incorporation thereof into an integral part of saidbase end portion, and extension thereof around the exterior of said base end portion as aforesaid.

Claims

2. A free standing antenna device as claimed in claim 1 including endwise extensions of some of said longitudinally extending strands of said glass fiber filaments extending through said cylindrical opening of said core member, said endwise filament extensions being folded around the exterior of said support surface and said core member and back up alongside a portion of said main body portion and bonded thereto and to said core member whereby to secure said core member integrally with said base end of said main body portion.
3. A free standing antenna device as claimed in claim 1 wherein said main body portion comprises upper and lower body sections separable from one another for shipping and storage, and when assembled together, forming said main body portion.
4. A free standing antenna device as claimed in claim 3 wherein said lower body section has lower and upper ends, said lower end comprising said base end of said main Body portion, and including coupling means on said upper end of said lower body section, and wherein said upper body section defines lower and upper ends, said upper section upper end defining said upper closed end of said main body portion, and coupling means on said upper section lower end for interengagement with said coupling means on said upper end of said lower body sections.
5. A free standing antenna device as claimed in claim 4 wherein said coupling means comprise a male exterior threaded coupling member on one said end, and a female interior threaded coupling member on the other said end.
6. A free standing antenna device as claimed in claim 4 including electrically conductive means extending along the length of each of said upper and lower body sections, said conductive means terminating at said coupling means, and including contact ring means incorporated in said coupling means, electrically connected with said electrically conductive means, and adapted to interengage with one another and make electrical connection through said coupling when said coupling means are interengaged with one another.
7. A free standing antenna device as claimed in claim 4 including at least one intermediate body section between said upper and lower body section, and coupling means at each end of said intermediate body section for interengagement with adjacent coupling means on adjacent said upper and lower body sections.
8. A free standing antenna device as claimed in claim 1 wherein said electrically conductive means comprise a plurality of separate electrical electrically conductive strips, said strips being embedded within said integrally bonded filament of said main body portion, along the major portion of their length, said electrically conductive strips being arranged in an extended spiral manner whereby to define at least a partial rotation relative to the axis of said main body portion.
9. A free standing antenna device as claimed in claim 1, wherein said longitudinally extending filament at least comprise a continuous strand of said filament, said strand being arranged to run from one end to the other of said main body portion along the length thereof and being formed into a loop at each end thereof, at least some of said strands of longitudinal filaments, at said base end of said main body being cut so as to permit incorporation thereof into an integral part of said base end portion, and extension thereof around the exterior of said base end portion as aforesaid.