EP1198649A2

EP1198649A2 - Environmentally compatible pole and piling

Info

Publication number: EP1198649A2
Application number: EP00945070A
Authority: EP
Inventors: Leon B. Hopper; Larmon Parker
Original assignee: Hopper Industries Inc
Current assignee: Hopper Industries Inc
Priority date: 1999-07-02
Filing date: 2000-06-30
Publication date: 2002-04-24
Also published as: CA2377933A1; WO2001002662A3; CN1367856A; AU5906200A; WO2001002662A2

Abstract

An elongated support structure (50, 193, 193a, 193b, 193c, 193d, 193e, 218) suitable for outdoor use as a utility pole, post, or piling and having a multiple layered, composite construction, and a method for manufacturing such an elongated support structure (50, 193, 193a, 193b, 193c, 193d, 193e, 218). The elongated support structure (50, 193, 193a, 193b, 193c, 193d, 193e, 218) includes a hollow core (68, 194, 194a, 194b, 204, 210) formed of a homogeneous mixture of a matrix resin and a fibrous strenghtening material. The core (68, 194, 194a, 194b, 204, 210) is surrounded by a reinforcing layer (72, 206, 212) of fiberglass and a binding resin. An expanded foam resin layer (74, 207, 209, 215, 217) is disposed on the exterior of the reinforcing layer (72, 206, 212). The interior of the core (68, 194, 194a, 194b, 204, 210) may be subdivided into smaller longitudinal compartments (199, 200, 201, 202, 203, 205) by a structural divider (196, 196a, 196b). The support structure (50, 193, 193a, 193b, 193c, 193d, 193e, 218) may have different cross-sectional configurations, utility poles using the elongated support structure (50, 193, 193a, 193b, 193c, 193d, 193e, 218) include accessories and attachments, such as cross arms (56, 220), cross arm mounting brackets (58, 222), guy wire brackets (236), power line connection brackets (130, 344, 346), and end caps (60, 64, 66, 228, 240, 242, 360). Extremely long support structures (218) are assembled with coupling accessories (268, 278) from shorter support sections (230, 230a, 230b).

Description

ENVIRONMENTALLY COMPATIBLE POLE AND PILING

BACKGROUND The Field of the Invention

The present invention relates to elongated support structures, such as utility poles and pilings, that are suited for outdoor use and capable of supporting signs, cross arms, railings, power lines, or other loads mounted thereto. The present invention pertains in addition to methods for manufacturing such support structures.

Background Art Elongated support structures such as those used as utility poles, pilings, flagpoles, and support members in buildings are commonly made from wood in the form of debarked and treated tree trunks. The wood poles used in many of these applications, particularly as utility poles, must be chemically treated to resist degradation from insects, weathering, and rot. Chemicals used for the treatment of wood utility poles include pentachlorophenol, chromium, copper, arsenic, and creosote. Poles treated with these chemicals are resistant to degradation, but leach heavy metals and harmful chemicals into the ground and the water system, creating long-term environmental hazards. Moreover, chemically treated poles must be disposed of as a hazardous waste.

When wood poles are used as utility poles, there is a concern for the safety of the workers who must climb the poles for routine maintenance and emergency service. The chemicals used in the treatment of utility poles can cause severe chemical burns on the utility line workers who handle or climb such poles. Such chemical injuries create wounds that are slow and difficult to heal. Wood poles develop rotten spots which may yield and tear out when a climbing spike is inserted in an attempt to gain foot support for the utility worker. Another hazard of wooden poles is that a climbing spike on a boot of a worker may hit a knot, which is very hard and prevents the spike from penetrating sufficiently to safely hold the worker. Similarly, the worker will not be supported if a climbing spike hits a crack which is too wide to secure the spike. Wooden poles thus create a significant danger of a slip or a fall, which can result in injuries to the worker from splinters, abrasions, or impacts with the ground, undergrowth, construction material, machinery and even other persons in the immediate vicinity. Such an accident can cause death or permanent injury. Wood poles are relatively electrically conductive. Thus insulators are usually required between wood poles and electrical wires that are mounted to the wood poles.

Wood poles are difficult to obtain in the longer lengths needed for high voltage power lines, and longer lengths of wood poles are heavy and difficult to transport and store. A number of alternatives to wood poles have been proposed. Various hollow fiberglass poles have been developed for use as utility poles. Fiberglass poles are lightweight in comparison to wood, durable, and do not leach hazardous materials into the environment. Fiberglass poles collapse easily, however, do not bear compressive loads as well as wood poles, and are susceptible to buckling under flexural or compressive loads. Care must be taken to distribute loads, as when bolting an attachment onto such poles, to avoid damage to the pole. Fiberglass poles are relatively hard and brittle, with a smooth exterior, and thus cannot be climbed by a worker using conventional climbing spikes. Steps must be installed on the exterior of fiberglass poles to permit them to be climbed.

Other alternatives to wood poles include metal and reinforced concrete structures. Such poles present the same problems as fiberglass poles in terms of climbability.

Moreover, metal and metal reinforced concrete are conductive and unsuited for use as poles for bearing electrical lines. Finally, these alternatives to wood poles cannot be readily constructed in the long lengths typically used for carrying high voltage power lines.

SUMMARY OF THE INVENTION

One object of the present invention is to provide an elongated support structure that reduces sources of chemical contamination in the environment.

Another object of the present invention is to provide such a support structure that does not leach hazardous materials during lengthy periods of installation and use. A general object of the invention is to provide elongated support structures for outdoor use that are economical to transport, to install, and to maintain.

Yet another object of the present invention is such a support structure that does not itself need to be disposed as a hazardous waste.

It is an object of the present invention is to provide an outdoor load-bearing utility pole that is resistant to environmental degradation from rot, insects, and weathering.

Another object of the present invention is to provide an elongated support structure that is of lighter weight than prior wooden poles. In addition, it is an object of the invention to provide such an elongated support structure that has enhanced resistance to failure under compressive and flexural loads.

Yet another object of the present invention is to provide an elongated support structure that is not limited as to length. Yet another object of the present invention is to provide markedly longer support structures that are also easily transported.

A further object of the invention is to provide an elongated support structure that is not electrically conductive

Another object of the present invention is to provide a utility pole with an exterior that is climbable and is resistant to degradation from rot, insects, and weathering.

Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.

To achieve the foregoing objects, and in accordance with the invention as embodied and broadly described herein, an elongated support structure is provided that includes an elongated core formed of a substantially homogeneous composite material and a reinforcing layer bonded to the outer surface of the core. The composite material from which the core is formed includes a matrix resin and a strengthening material of fine, elongated particles. The strengthening material intermixed with the resin is fibers of a length in a range of about 0.50 - 4.00 inches. Such fibrous material can be produced from wood shreds, coconut husks, palm bark, hemp, sisal, or bagasse from which substantially all moisture, resins, and sap has been removed. The resin in which the strengthening material is mixed can be phenolic or polymeric resins that are cured by heat.

The elongated core is extruded from the liquid composite material of matrix resin and strengthening material. In many instances, the core is hollow, so that the interior of the core encloses a centrally disposed lumen that extends longitudinally between the opposite ends of the core. The lumen in the core may be divided into longitudinal compartments by a structural divider that is integral with the core. The structural divider can assume numerous and complex configurations. The reinforcing layer bonded to the outer surface of the core includes a binding resin and reinforcing fibers embedded in the binding resin. The reinforcing fibers may be in the form of fiberglass roving, fiberglass matting, and fiberglass surfacing veil. The binding resin may be identical to or different from the matrix resin. Ultraviolet inhibitors, insect repellents, and colorants may be added to the binding resin as appropriate.

According to one aspect of the present invention, an elongated support structure as described above is provided with climbing facilitation means on the exterior of the reinforcing layer for receiving the climbing spikes of a worker. By way of example and not limitation, such a climb facilitation means can take the form of a climbing layer made of expanded foam resin that is bonded to the outer surface of the reinforcing layer. The climbing layer has a combination of density and strength sufficient to support the climbing spikes of a worker weighed down with equipment. The climbing layer is comprised of resins such as polyurethane, polyvinyl chloride, polypropylene, and synthetic rubber.

A support structure of the type described above is capable of being erected vertically or horizontally and bearing signs, cross arms, railings, power lines, or other loads that are attached to the support structure.

According to teachings of the present invention, support structure of extreme elongation can be manufactured from shorter first and second pole sections structured as described above that are interconnected in aligned end-to-end relationship at a coupling joint. Each of the pole sections has an end face at the coupling joint in which a coupling recess is formed.

According to another aspect of the present invention, means are provided for securing the first and second pole sections. By way of example and not limitation, such a means for securing includes a connector dowel having first and second ends. The connector dowel traverses the coupling joint with the first end of the coupling dowel receiving the coupling recess in the end face of the first pole section and the second end of the coupling dowel received in the coupling recess in the end face of the second pole section.

A coupling joint stabilization plate is provided having a centrally located aperture. The opposite sides of the stabilization plate are engaged by corresponding end faces of the first and second pole sections while a medial portion of the connecting dowel extends through the aperture in the stabilization plate. The periphery of the stabilization plate projects at the coupling joint radially outwardly of the exterior of the first and second pole sections, thereby to support hardware with which to stabilize the assembled structure using guy wires.

The present invention includes methods for manufacturing an elongated support structure of the type described. A substantially homogeneous mixture of a matrix resin and a strengthening material of fine elongated particles intermixed with the matrix resin is extruded into an elongated core. A reinforcing layer made of a binding resin and reinforcing fibers embedded in the binding resin is applied to the exterior of the core. The reinforcing layer is cured using heat that is externally applied or that is generated by a catalyst.

A layer of expanded foam may be formed on all or portions of the exterior of the reinforcing layer. To do so, a resin and a foaming agent are introduced into a foam expansion chamber. An elongated structural member is advanced longitudinally through the foam expansion chamber, causing a layer of expanded foam to adhere to the exterior of the structural member.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the manner in which the above-recited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to a specific embodiment thereof which is illustrated in the appended drawings. Understanding that these drawings depict only a typical embodiment of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: Figure 1 is a perspective view of the outdoor environment in which poles and pilings incorporating teachings of the present invention find utility;

Figure 2 is a perspective view of an embodiment of a utility pole incorporating teachings of the present invention;

Figure 3 is an exploded disassembled perspective view of the components at the top of the utility pole of Figure 2;

Figure 4 is a perspective view of the internal layered structure of the vertical support structure in the utility pole of Figure 2 taken along section line 4-4 shown therein; Figure 5 is a cross section of the cross arm of the utility pole of Figure 2 taken along section line 5-5 shown in Figure 3;

Figure 6 is a schematic illustration of a method for manufacturing the vertical support structure and the cross arm of the utility pole of Figure 2; Figure 7 is a cross section of a second embodiment of a support structure incorporating teachings of the present invention;

Figure 8 is a cross section of a third embodiment of a support structure incorporating teachings of the present invention;

Figure 9 is a cross section of a fourth embodiment of a support structure incorporating teachings of the present invention;

Figure 10 is a cross section of a fifth embodiment of a support structure incorporating teachings of the present invention;

Figure 11 is a cross section of a sixth embodiment of a support structure incorporating teachings of the present invention; Figure 12 is a cross section of a seventh embodiment of a support structure incorporating teachings of the present invention;

Figure 13 is a perspective view of an embodiment of a utility transmission support incorporating teachings of the present invention;

Figure 14 is an enlarged perspective view of guy wire attachment hardware at a coupling joint between adjacent ends of constituent pole sections in a vertical support structure in the utility transmission support of Figure 13;

Figure 15 is an exploded disassembled perspective view of the guy wire attachment hardware of Figure 13;

Figure 16 is an exploded disassembled perspective view of the coupling joint shown in Figure 15;

Figure 17 is an assembled elevation cross section of the guy wire attachment hardware and the coupling joint of Figure 14 taken along section line 17-17 shown therein;

Figure 18 is an exploded disassembled perspective view of the components at the top of a vertical support structure in the utility transmission support of Figure 13; Figure 19 is an enlarged perspective view of hardware for securing electrical cables to a cross bar of the utility transmission support of Figure 13; and Figure 20 is a perspective view of an embodiment of an end cap for a vertical support structure of the utility transmission support of Figure 13 configured to encourage nesting by birds.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Depicted in Figure 1 is an outdoor environment in which elongated support structures incorporating teachings of the present invention may be used. Possible applications of the invention include electrical poles 10, telephone poles 12, street lamp poles 14 and traffic light poles 16. The invention may also find application in guard rail supports 18 or 20, railings 22 or 24, sign posts 26, boat masts 28, utility pole cross arms 30 and boat mast cross arm 32. The invention may also be used in pilings 34 for supporting docks or bridges, supports 36 for structures such as benches, and structural elements 38 used in building construction.

A vertical support 50 incorporating teachings of the present invention and used as a utility pole for carrying telephone or electrical lines is depicted in Figure 2 installed in the ground 52. Utility lines 54 are attached to a cross arm 56, which is attached to mounting bracket 58 and thereby to vertical support 50. Although a single cross arm 56 is shown in Figure 2, a plurality of cross arms 56 may be attached to vertical support 50 as needed. As shown in the broken region of vertical support 50, vertical support 50 is a hollow structure that encloses a longitudinally extending lumen 70.

An end cap 60 covers upper end 62 of vertical support 50, and end caps 64 cover the ends of cross arm 56. A flattened end cap 66 covers the lower end of vertical support 50, to prevent moisture from the ground 52 from entering the interior of the vertical support 50. Figure 3 is an exploded disassembled perspective view of the components at the top of vertical support 50, in the circled region 3-3 in Figure 2. Lumen 70 opens to the exterior of vertical support 50. End cap 60 includes a rounded outer surface 94, an abutment surface 92, and a projecting attachment peg 84. Attachment peg 84 is received in lumen 70 and secured with a nut 91 and a throughbolt 86 that is passed through a hole 88 in vertical support 50 and a hole 90 in attachment peg 84. Alternatively or in addition to throughbolt 86, an adhesive could be used to secure end cap 60 to vertical support 50. It is also appropriate to fasten abutment surface 92 of end cap 60 to vertical support 50 with an adhesive, obviating the need for an attachment peg such as attachment peg 84. End cap 60 may be formed from the same material as used for core 68, or from various other materials, including resins, plastics, and resin composites.

Mounting bracket 58 includes a first mounting bracket half 96 and a second mounting bracket half 98 that are clamped about vertical support 50 by a nut 106 and a throughbolt 100 that is passed through a hole 102 in first mounting bracket half 96, a hole 103 in vertical support 50, and a hole 104 in second mounting bracket half 98. Inner surfaces 108 and 109 of mounting bracket halves 96 and 98, respectively, are curved to correspond to the exterior of vertical support 50. Climbing layer 74 is removed from the uppermost portion of vertical support 50 above upper terminus 105 of climbing layer 74 so that inner surface 108 and inner surface 109 fit directly against reinforcing layer 72.

Cross arm 56 is secured to mounting bracket 58 with nuts 113 and bolts 110, which are passed through holes 107 in cross arm 56, holes 111 in first mounting bracket half 96, and holes 112 in second mounting bracket half 98. Grooves 114 and 116 on the outer face of first mounting bracket half 96 receive corresponding ridges 118 and 120, respectively, on cross arm 56 to ensure proper alignment and secure attachment of cross arm 56. Second mounting bracket half 98 includes comparable grooves 122 and 124 to facilitate attachment of another cross arm 56, if such is desired. One side of cross arm 56 is provided with longitudinally extending ridges 118 and 120. On the opposite side of cross arm 56 are similar ridges 126 and 128.

End caps 64 are attached to the extremities of cross arm 56 with an adhesive, or end caps 64 may be press fitted therewith. Utility line 54 may be secured to cross arm 56 by various types of hardware. One example is clamp 130 secured to cross arm 56 by screw 132. According to the invention, cross arm 56 is formed of electrically nonconductive material. Thus, no electrical insulators are required in the attachment of utility lines 54 to cross arm 56.

The interior structure of vertical support 50 is shown schematically in Figure 4. There it can be seen that vertical support 50 is a layered structure. At the center of vertical support 50 is a hollow core 68 that encloses longitudinally extending lumen 70. Core 68 is made of a substantially homogeneous composite mixture of a fibrous strengthening material and a suitable matrix resin that will be described in detail subsequently. Bonded to the exterior of core 68 is a reinforcing layer 72 made of fibers embedded in a binding resin. Reinforcing layer 72 generally terminates at the same axial end surfaces as each of the ends of core 68.

On the exterior of reinforcing layer 72 is a climbing layer 74 that is formed of an expanded foam resin material. Climbing layer 74 has an outer surface 82. As shown in Figure 2, a worker 76 climbs vertical support 50 using a safety belt 80 and climbing spikes 78 that are attached to the boots of worker 76. Climbing layer 74, shown in Figure 4, is made of a material which will receive climbing spikes 78 and thereby support worker 76 and the equipment thereof, while worker 76 climbs vertical support 50 or stops in place on vertical support 50 with climbing spikes 76 dug into climbing layer 74. The material of which climbing layer 74 is made is such that puncture holes and slits made by climbing spikes 78 tend to close once climbing spikes 78 are removed. Safety belt 80 of worker 76 is braced against outer surface 82 of climbing layer 74 to assist in supporting worker 76. Therefore, outer surface 82 may be roughened to inhibit slippage of safety belt.

Core 68 in combination with reinforcing layer 72 provide the structural strength of the vertical support 50. Thus, a vertical support constructed with just these two types of layers would be fully functional to support loads. Nonetheless, due to the material properties of reinforcing layer 72, such a support structure would typically have a hard outer surface that is not readily climbable.

Therefore where a climbable support structure is required, according to an aspect of the present invention, an elongated support structure includes climb facilitation means for receiving climbing spikes is provided on the exterior of reinforcing layer 72. As shown by way of example in Figure 4, a structure capable of performing the function of a climb facilitation means according to teachings of the present invention is climbing layer 74 of the type described above. Alternatively, but with less elegance, steps secured to the exterior of a support structure that includes only core 68 and reinforcing layer 72 could be used to perform the function of a climb facilitation means.

In a support structure that is not likely to be climbed by a worker, climbing layer 74 can be omitted. This would be the case, for example, in a utility pole cross arm, a sign post, or a guard rail. Figure 5 is a cross section of cross arm 56, taken along section line 5-5 in Figure 3.

Cross arm 56 includes a core 134 having a longitudinally extending lumen 136. A reinforcing layer 138 is bonded to the exterior of core 134. Core 134 can be formed of the same type of composite mixture of fibrous strengthening material and matrix resin as used in core 68 of vertical support 50. Specific materials used in core 134 and reinforcing layer 138 will be discussed below. Cross arm 56 as shown has a square outer cross section, with ridges 118, 120, 126 and 128 to engage with corresponding grooves in mounting bracket 58 used to attach cross arm 56 to vertical support 50. Cross arm 56 could, in the alternative, have a rectangular or circular cross section.

Core 68 of vertical support 50 and core 134 of cross arm 56 are formed of a substantially homogenous composite mixture of fibrous strengthening material in a matrix resin. The fibrous strengthening material is made up of fine elongated fibers ranging from about 0.5 to 4.0 inches long. Fibers in the range of about 0.75 to 2.0 inches long have been found to be particularly suitable. Fibers which are too short do not provide the desired strength to the core, while longer fibers may not move readily through mixing equipment used in the manufacturing process. Various natural and man-made fibrous materials may be used, including, but not limited to, chopped fiberglass, polymer fibers such as Kevlar™, carbon fibers, wood fibers, coconut husks, sisal, bagasse, tree fibers, palm bark, hemp, and rice husks.

Wood fibers for use in the composite mixture are shredded or chipped from green or freshly-cut tree stock. If the wood has been chipped, the chips are shredded into fiber form. The tree stock may be from any suitable evergreen or deciduous trees. It may be desirable to use fast-growing trees such as long leaf pine or slash pine to assure a continuing source of material. Scrap wood from sawmills, or undesirable or trash trees may also be used. Any tree material can be used that is readily available, reducible to wood shreds, and can be freed of substantially all moisture, resins, and sap.

An example of a suitable resin for use in the composite mixture as a matrix resin is a Borden Chemical, Inc., resin having the trade name of DURITE SC-830A. DURITE SC-830A resin is a phenolic resin available in either liquid or pellet form. Examples of other resins or polymers that may be used are polyvinyl chloride, polyurethane, polypropylene, and various co-polymers. The choice of a particular resin or polymer depends upon the properties of the cured form of the material, as they influence the desired long-term performance and durability of the elongated support structure in the intended use environment. Elongated support structure made in accordance with the teachings of the present invention will remain functional for 20 to 40 years or longer, even in the presence of extreme weather conditions and natural enemies of wood products, insects, molds, and wildlife. A cured resin in an elongated support structure constructed according to teachings of the present invention should meet the following minimum strength requirements over the lifetime of the support structure: Flexural Strength: 36,500 p.s.i.

Flexural Modulus: 1,750,000 p.s.i.

Compressive Strength: 29,000 p.s.i. Tensile Strength: 23,000 p.s.i.

More optimally, however, resins meeting the following strength requirements are available and are recommended:

Flexural Strength: 73,000 p.s.i.

Flexural Modulus: 3,500,000 p.s.i. Comprehensive Strength: 58,000 p.s.i.

Tensile Strength: 46,000 p.s.i.

As new resins are developed with higher strengths, these new resources will undoubtedly find utility in the fabrication of structural members according to the teachings of the present invention. It is desirable to have a mixture of fibrous material and liquid resin by volume of about 70% fibrous material and 30% liquid resin. A range of 65-75% fibrous material is typically acceptable. This ratio can be modified to some extent, to as low a concentration of fibrous material as 50%, with 50% liquid resin, for example, or to as high a concentration of about 85% fibrous material and 15% liquid resin, so long as the ultimate strength of the final product vertical support is within limits to perform as expected under specified conditions for many years. The percentage of fibrous material used must be selected to balance the pole flexibility, compressive and tensile strength characteristics for the intended application with the cost and availability of the component materials. These percentages are directed to the two main ingredients, and are not to be construed to be required to omit such relatively nominal percentage additives such as ultraviolet inhibitors, insect repellents, fire retardants, and coloring, that may be added to the mixture.

Figure 6 illustrates a method of manufacturing vertical support 50 or cross arm 56 as shown in Figures 2-5. The fibrous materials used in this example are placed in drying station 140 where the moisture, gum, resins and saps are driven off by a distillation process which includes heating the wood fibers to convert the moisture and other liquids to a gaseous form which can be removed from the shreds. Substantially all of the moisture and other liquids should be removed. In this case, substantially all is defined as greater than 98%. Heated gum, resins and saps from the fibrous materials are collected in collector 142, which may include a vacuum removal arrangement or other separator equipment that expedite and more completely accomplish the removal of these materials. This is done at a temperature in the range of about 250 to 280° F. The mixture of gaseous and liquid material removed from the fibrous material is collected by collector 142 as part of the distillation process and any gaseous materials are reduced to a liquid form. In some countries, environmental protection programs may require that distillates be collected rather than released to the environment. Whether or not required, it can often be of economic as well as environmental benefit to gather the distillates to be used for other purposes. Following the drying process, the fibrous materials are light, porous, very dry, and able to readily absorb the resins used in the next step. The shredded and dried fibrous materials are conveyed from drying station 140, preferably still at or near the temperature they reached at the end of the drying process, into feeder unit 144, which in turn directs the fibrous material into the mixing tank 146.

Pelletized resin is heated in a dry heat container 148 to the temperature required to cause the resin pellets to melt and assume a liquid form. A temperature of about 220° F is required to melt pellets of phenol resin. If liquid resin is employed, the amount of water or other thinning agent therein should be minimized. Otherwise, such water or other thinning agent in the liquid resin may become trapped during curing within the composite mixture, creating voids. To minimize the formation of such voids, a separate preheating step may be employed to drive water and thinning agents out of the liquid resin. Governmental standards may prevent some such thinning agents from being vented into the atmosphere. If such thinning agents are present in the liquid resin, these must be trapped for disposal after being boiled off. This can be an unwanted expense. The liquid resin is directed into a feeder unit 150, which supplies the liquid resin into the mixing tank 146 at a predetermined rate, concurrently with fibrous material from feeder unit 144. The resin in mixing tank 146 is raised to a temperature where it is at or very near its most viscous stage but is still below the temperature at which it will self-cure or be cured with added hardener. For example, the temperature of phenol resin at this stage is in the range of 280 to 325 ° F.

The fibrous material remains in contact with the heated liquid resin in the mixing tank 146 until the shreds of fibrous material are completely saturated with the resin. This is accomplished by mixing the fibrous material and the liquid resin until a substantially homogeneous mixture is attained. The desired saturation is expedited by the absorbent nature of the fibrous material combined with a vigorous stirring and mixing action. Saturation virtually eliminates small pockets of air or other gaseous material which may create voids in what is intended to be a solid, void-free core. It is not generally necessary to use pressure to obtain complete saturation and homogeneity. During mixing in mixing tank 146, other compounds such as ultraviolet inhibitors, insect repellents, fire retardants and colorants may be added to the mixture.

The homogenous mixture of saturated fibrous material and resin is transported by auger 153 from mixing tank 146 into a heated extruder resin chamber 152. Immediately prior to injection into an extruder chamber 154, the homogenous mixture is superheated to a resin curing temperature of about 350-375 ° F. The proper curing temperature range depends, however, upon the particular resin being used, so the curing temperature range may be higher or lower for other resins.

The homogeneous mixture is then extruded under pressure through the feed throat 156 into the heated extruding die barrel 158. For making a typical 45 foot long utility pole, extruding die barrel 158 may have an inner diameter of 10.0 inches, for example. The homogeneous mixture is extruded with a 7.0 inch outer diameter heated mandrel 160 capable of extending about 40 feet into the heated extruding die barrel 158. The extruded core 162 becomes a tubular member having a ten inch outer diameter and a seven inch inner diameter, with the wall thereof having a radial thickness of 1.5 inches. Of course, other cross-section sizes and wall thicknesses may be made by changing the inner diameter of the extruding die barrel 158 and the diameter of the mandrel 160 as desired. The ten inch outer diameter, seven inch inner diameter, extruded core 162 is satisfactory as a core for a 45-foot long utility pole, and is described here as a typical size for that purpose. Extruded core 162 of Figure 6 becomes core 68 of Figure 4.

In order to form an extruded core 162 suitable for use as core 134 of cross arm 56, a smaller extruding die barrel 158 and mandrel 160 would be used. Examples of suitable dimensions for die barrel 158 are 4.0 inches by 4.0 inches, with mandrel 160 having corresponding dimensions of 2.0 inches by 2.0 inches.

The feed rate through extruding die barrel 158 is preferably about 1.5 to 2.5 feet per minute and the compaction density is preferably within a range of about 400 to 600 p.s.i. The temperature of the interior of extruding die barrel 158 is controlled by heating the barrel to a desired resin curing temperature, and is such that the resin of the homogeneous mixture composed of resin and the wood shreds is cured as extruded core 162 passes through die barrel 158. This curing temperature is within the range of 350 to 375° F. for DURITE SC-830A resin. It is modified as appropriate when other resins are employed. This extrusion and curing process step forms the tubular core of what will become a finished pole.

Extruded core 162 passes out of heated extruding die barrel 158 and engages a set of V-shaped rollers that are not shown in Figure 6 that help maintain extruded core 162 in a straight line as it is being directed into a heated continuous feed die 164 such as a pultrusion die. A die of this type was developed by Martin Pultrusion, and the technology is currently owned by the Morrison Molded Fiberglass Company. Another company, Pultrusion Dynamics, Inc. manufactures pultrusion equipment.

As extruded core 162 exits extruding die barrel 158 for the first time at the beginning of a continuous extruding run, a removable ring 166 is placed on the extruded core 162 leading end at the beginning of the initial feed into the continuous feed die 164. Ring 166 fits around the circumference of extruded core 162. Attached to ring 166 are the ends of several fiberglass rovings 168 and fiberglass matting 170 fed by creels 172 and 174, respectively, located in the vicinity of the outer end of extruding die barrel 158.

Matting 170 is unidirectionally woven or otherwise formed, and is longitudinally disposed on extruded core 162 in overlapping layers of continuous filament mat. The overlapping portions of adjacent strips of matting 170 may be reinforced by the longitudinal disposition at such overlapping portions of narrower strips of a similar material. For example, where matting 170 is about 16.0 inches in width with overlapping portions between adjacent pieces of matting 170 being about 2.0 inches in extent, narrower reinforcing strips of about 3.0 inches in width are applied at the overlapping portions.

Fiberglass rovings 168 and matting 170 are dispensed from creels 172 and 174 as extruded core 162 moves longitudinally into continuous feed die 164. Rovings 168 and mattings 170 are coated with binding resin from the resin supply 176 as they are being pressed and formed onto the still hot extruded core 162 to form reinforcing layer 72 in Figure 4 or 138 in Figure 5. Reinforcing layer 72 or 138 may also include spirally wound fibers or surfacing veil. In place of glass fibers, carbon or polymer fibers such as Kevlar™ could be used. The heat of continuous feed die 164 cures the binding resin coating the fiberglass rovings 168 and matting 170 and also bonds rovings 168 and matting 170 to extruded core 162. When extruded core 162 leading end exits continuous feed die 164, feed ring 166 is removed. Feed ring 166 is no longer needed as long as fiberglass rovings 168 and mattings 170 continue to be applied from creels 172 and 174 to the exterior surface of extruded core 162. Reinforcing layer 72 on a vertical support structure provides satisfactory strength when it is about 5/16 of an inch thick. Reinforcing layer 138 on a typical cross arm will provide sufficient strength if manufactured to a thickness of between 0.0625 and 0.125 inches.

The binding resin from resin supply 176 used in the reinforcing layer can be selected from the same group of resins as the matrix resin used in the mixture from which extruded core 162 is formed. Identical resins can be used in the core and reinforcing layer, or two different resins can be used, providing good adhesion between the two is obtained and curing temperatures are close enough to avoid one resin becoming brittle as the other is cured. The reinforcing layer and the extruded core 162 form a single fiberglass encapsulated composite unit 178. As composite unit 178 exits continuous feed die 164, it is gripped by a set of tractor feed pullers 180, such as Gatto Tractor Pullers, that assist in feeding out composite unit 178. Composite unit 178 is directed onto another V-roller assembly, also not shown in Figure 6, and is guided into a foam expansion chamber 182. Foam expansion chamber 182 has an inside diameter larger than the outside diameter of composite unit 178. The space between the exterior of composite unit 178 and the interior of foam expansion chamber 182 defines the thickness of the expanded foam layer 186 formed therein. The shape of the interior of foam expansion chamber 182 defines the exterior shape of expanded foam layer 186.

A polyurethane resin from a source 184 and a foaming agent from a source 185 are injected simultaneously into foam expansion chamber 182. In foam expansion chamber 182 the resin in combination with the foaming agent grows into an expanded closed-cell foam resin. By passing composite unit 178 through foam expansion chamber 182, an expanded foam layer 186 is deposited on the exterior of composite unit 178. In the present example, expanded foam layer 186 has a thickness of about 1.50 inches, so that final product 188 has an outer diameter of 13.625 inches. Expanded foam layer 186 becomes climbing layer 74 of Figure 4.

Expanded foam layer 186 and composite unit 178 are bonded together during the foam expansion operation to form final product 188. The curing of the expanded foam on composite unit 178 takes place in foam expansion chamber 182 under the influence of heat and pressure. The resin used to form expanded foam layer 186 may be polyurethane, polyvinylchloride, synthetic rubber, or other materials having similar properties. The properties of expanded foam layer 186 must be sufficient to support climbing spikes of a worker weighed with equipment. A density of between 1.0 to 30 pounds per cubic foot is considered sufficient to the requirements of the invention, while densities between about 2.0 to 25 pounds per cubic foot are preferable, and densities between about 3.0 to 15 pounds per cubic foot are optimum.

If climbing layer 74 is not sufficiently dense, climbing spikes will tend to tear therethrough and therefore not provide firm support for a worker. If climbing layer 74 is overly dense, a worker will encounter difficulty in sufficiently penetrating the climbing layer with climbing spikes. The tendency of the puncture sites in climbing layer 74 to close after climbing spikes are withdrawn is also affected by the density of climbing layer

74. Climbing layer 74 is sufficiently thick to accommodate the climbing spikes of a worker without encountering the harder material of fiberglass coated composite unit 178.

Expanded foam layer 186 may be colored as desired before or during the introduction of resin into the heated foam expansion chamber 182. For example, expanded foam layer 186 can be colored to resemble a tree trunk, thus being less visually obtrusive if that characteristic is desired in some areas, or can be color coded for other identification or aesthetic purposes. Expanded foam layer 186 can also be provided with bio-luminescent material to improve visibility of vertical support 50. This visibility can be an important safety factor in preventing accidental collisions of vehicles with vertical supports, and consequently also in preventing outages of electricity, telephone and cable services that may be caused by such collisions.

After final product 188 exits foam expansion chamber 182, it is cut into the desired length for each vertical support by a cutting tool 190 such as a saw. Because the manufacturing process, once started, is a continuous process, the cutting saw is preprogrammed to make the desired length cut, does so while traveling alongside and at precisely the same linear speed as the moving finished unit while making the cut, and, after completion of the cut, then returns to its initial position to be ready to make the next cut.

Having been cut to a desired length, final product 188 is conveyed to a final curing rack, not shown in Figure 6. There final product 188 is inspected and tagged. The tag may provide a lot number, the number of the particular vertical support, date and place of manufacture, and other appropriate information. Final product 188 may also be predrilled for later attachment of the cross arm mounting brackets, pole end caps, or other attachments.

If desired, there may be a final inspection by use of ultrasound or other known inspection devices 192, such as spectrographs or X-rays, to detect interior changes in density beyond an acceptable density variation caused by nonvisible flaws such as small air or moisture pockets. This inspection can be automatically performed as final product 188 exits foam expansion chamber 182. Any portion of final product 188 found to have a flaw that portion is sawed off by cutting tool 190. This allows for less waste of final product 188 than if full lengths of final product 188 are rejected. Once started the production is a continuous in-line extruding, molding and curing operation. If different support member lengths are required, it is a simple matter to adjust the length of the support members by cutting at the end of the manufacturing process. If a shorter support member is required, a full length support member can be cut to the desired length and provided with caps and other accessories as needed. Cross arm 56, as shown in Figures 2, 3 and 5, is formed in the same manner as vertical support 50, using the same type of composite core and reinforcing layer and using suitable extruding die barrel 158, mandrel 160 and continuous feed die 164 to obtain the desired cross sectional shape. Cross arm 56 may be provided with a colored exterior surface similar to vertical support 50 if desired, but need not be covered by a thick expanded foam layer. Thus, the manufacturing process is completed after the product has passed through continuous feed die 164. In a further embodiment of the invention, a climbing layer comparable to expanded foam layer 186 is applied to an elongated support structure other than fiberglass encapsulated composite unit 178 described in connection with the process of Figure 6. Other elongated support structures which may be used in this embodiment of the invention include any prior art elongated support structures, as well as any elongated support structures which may be developed in the future, to which a expanded foam layer can be bonded. The expanded foam layer is formed and cured directly on the elongated support structure and within a foam expansion chamber, as shown in Figure 6. Alternatively, a preformed expanded foam layer could be bonded to the exterior of the elongated support structure with a suitable adhesive. Figures 7-12 depict in cross-section additional embodiments of support structures incorporating teachings of the present invention.

Figure 7 depicts an alternative embodiment of the inventive vertical support 193 which could be used, for example, as a utility pole. Vertical support 193 includes core 194, reinforcing layer 72, and climbing layer 74. Reinforcing layer 72 and climbing layer 74 are circular, and are as shown in Figure 4. Core 194 is made up of shell 195 and structural divider 196. Shell 195 is circular in cross section and comparable to core 68 of the embodiment of Figure 4.

Structural divider 196 is made up of three spokes 198 radiating outwardly from central hub 197 in a Y-shape to the interior of shell 195. Lumen 70, as shown in Figure 4, has been divided by spokes 198 into three longitudinal compartments 199. The cross section of Figure 7 is representative of the cross section of vertical support 193 along the entire length thereof. Thus, structural divider 196 is an elongated structure that extends the entire length of utility pole 193 , as do compartments 199. Electrical or telephone wires may be passed through compartments 199, grouped according to function individual of compartments 199. Structural divider 196 also provides additional strength to vertical support 193. In order to manufacture a core having multiple compartments, such as core 194 in Figure 7, the homogeneous mixture used to form core 195 is extruded over a sectional mandrel 160. Each section of the mandrel is shaped like one of compartments 199. The circular outer surface of core 194 is produced by using a circular extruding die barrel 158. The inner surface of reinforcing layer 72 conforms to the outer surface of core 194, while the outer surface of reinforcing layer 72 is determined by the shape of continuous feed die 164, which in the case shown in Figure 7 is circular. The inner surface of climbing layer 74 conforms to the shape of the outer surface of reinforcing layer 72, and the outer surface 82 of climbing layer 72 is determined by the shape of the interior of foam expansion chamber 182.

Figure 8 shows a further alternative embodiment of the vertical support. The vertical support 193a includes a core 194a, a reinforcing layer 72, and a climbing layer 209 having an outer surface 219. Reinforcing layer 72 is as shown in Figures 4 and 7. Core 194a is made up of shell 195a and structural divider 196a. Shell 195a is circular in cross section. Structural divider 196a includes a central hub 197a and four spokes 198a radiating outward from central hub 197a in an X-shape and connecting to the interior of shell 195a. Spokes 198a divide the interior of utility pole 193a into four peripheral compartments 201. Central hub 197a is a circle enclosing a central compartment 200. In three dimensions, hub 197a is an elongated cylindrical element positioned in coaxial relationship with shell 195a, attached to the interior of shell 195a by four elongated, parallel, longitudinally extending fins.

While climbing layer 74 is fully encircling of the exterior of reinforcing layer 72 in the embodiments of Figures 4 and 7, it is possible without departing from the teachings of the present invention to attach a expanded foam layer to but a portion of the exterior of reinforcing layer 72. Expanded foam climbing layers of this type could assume the form of a plurality of distinct pieces or strips of expanded foam attached to only portions of the reinforcing layer 72. For example, as shown in Figure 8, climbing layer 209 is two strips of expanded foam 215 and 217 extending the entire length of vertical support 193 a on opposite sides. Figure 9 shows a further embodiment of the vertical support . Vertical support

193b includes core 194b and reinforcing layer 72. The climbing layer has been omitted. Reinforcing layer 72 is as in the embodiments of Figures 4, 7, and 8. Core 194b is made up of shell 195b and structural divider 196b. Shell 195b is circular in cross section and comparable to core 68 of the embodiment of Figure 4. Structural divider 196b is made up of central hub 197b, which is hexagonal in shape and has a central compartment 202, which is also hexagonal in shape. Six spokes 198b extend radially outwardly from each vertex of hub 197b to the interior of shell 195b. The interior of shell 195b, the exterior of hub 197b, and the sides of spokes 198b define the boundaries of six peripheral compartments 203. The manufacture of utility pole 193b is comparable to that of utility pole 193, differing only in the shape of the sectional mandrel, which corresponds to the configuration of central compartment 202 and peripheral compartments 203 in Figure 9. Figure 10 depicts another embodiment of a vertical support that includes neither a climbing layer nor a structural divider. Utility pole 193c includes a circular core 68, a central lumen 70 within core 68, and a circular reinforcing layer 72. It is like utility pole 50 shown in Figure 4, but omits climbing layer 74, present in that figure. In order to manufacture a utility pole having a single lumen, such as lumen 70 in utility pole 193c, the homogeneous mixture used to form core 68 is extruded over a solid mandrel 160, which would be circular in this case to produce circular lumen 70. The circular outer surface of core 68 is produced by using a circular extruding die barrel 158. The inner surface of reinforcing layer 72 conforms to the outer surface of core 68, and the outer surface of reinforcing layer 72 is determined by the shape of continuous feed die 164, which in this case is circular.

As shown in Figure 11 , vertical support constructed according to the invention need not be circular in cross section. Utility pole 193d includes a core 204, reinforcing layer 206, and climbing layer 207, each of which is hexagonal in cross sectional shape. The interior of core 204 defines a lumen 205 also having a hexagonal cross section. Climbing layer 207 includes an outer surface 208. Utility pole 193d is manufactured as described above using a solid, hexagonal mandrel 160, hexagonal extruding die barrel 158, hexagonal continuous feed die 164, and hexagonal interior in foam expansion chamber 182.

As shown in Figure 12, it is not necessary for the various layers of the vertical support to have the same inner and outer cross sectional shapes. Vertical support 193e includes a core 210 and a reinforcing layer 212. The inner surface of core 210 defines a lumen 211 that has a clover leaf cross section. The outer surface of core 210 is by contrast circular in cross section. The inner surface of reinforcing layer 212 has a circular cross section matching the outer surface 213 of core 210, but the outer surface 213 of reinforcing layer 212 is octagonal. Vertical support 193e is manufactured as described above, using a solid, mandrel 160 having a clover leaf cross section, circular extruding die barrel 158, and an octagonal continuous feed die 164.

Figure 13 depicts an embodiment of a utility transmission support 216 incorporates teachings of the present invention. Utility transmission support 216 includes a pair of sectional poles 218, two cross arms 220 attached to sectional poles 218 by mounting brackets 222, and a pair of cross braces 224. Utility transmission support 216 may be used, for example, to support high voltage power lines. The lower ends of sectional poles 218 are installed in the ground 226. End caps 228 on the lower ends of sectional poles 218 include footings 214 that stabilize and prevent sinking of sectional poles 218 in soft ground.

Each sectional pole 218 is formed of several pole sections 230 aligned and joined in end-to-end relationship at coupling joints 232. In this application, two layer pole sections are used that include a core and reinforcing layer, like that shown in Figure 10.

Utility transmission support 216 is stabilized by guy wires 234 attached to guy wire securement collars 236 and secured to the ground 226 by, for example, anchor 238.

Poles 218 include end caps 240, and cross arms 220 include plugs 242 in the ends 248 thereof. Power lines 244 are attached near the ends 248 of cross arms 220. The components in the circled regions around coupling joint 232, pole upper end 246, and cross arm end 248 are shown in greater detail in Figures 14, 18 and 19, respectively. Additional hardware such as, for example, sign 250 or lamp 252, may be attached to poles 218 if desired. Figure 14 provides a close-up view of coupling joint 232, including guy wire securement collar 236. Two pole sections 230a and 230b are joined at coupling joint 232. Pole section 230a is positioned above coupling joint 232 and pole section 230b is positioned below coupling joint 232; otherwise, pole sections 230a and 230b are identical. Guy wire securement collar 236 is made up of first collar half 258 and second collar half 260 which fit around and encircle upper pole section 230a and are joined by nuts 272 and bolts 262 and eye bolts 264 at flanges 266. Eye bolt 264 has a loop sized to receive guy wire 234 for attachment thereto. Guy wire securement collar 236 engages with the upper side of coupling joint stabilization plate 268 extending between the outer surface of the pole sections and the periphery of coupling joint stabilization plate 268.

Figure 15 shows a first pole section 230a and a second pole section 230b joined at coupling joint 232 and guy wire securement collar 236 shown in exploded view. Guy collar half 258 and guy collar half 260 are connected by nuts 272 and bolts 262, 264, that are passed through holes 270 in guy collar halves 258, 260. Coupling joint stabilization plate 268 extends outwardly from coupling joint 232, thus providing a rim on which guy wire securement collar 236 can rest.

Figure 16 is an exploded view of coupling joint 232 that reveals structures that perform the function of securing first pole section 230a and second pole section 230b in end-to-end relationship according to teachings of the present invention. Shown by way of example and not limitation, is a connector dowel 278 that has a first end 280 received in a coupling recess 282 in first pole section 230a and a second end 284 received in a coupling recess 286 in second pole section 230b. Positioning projection 288 is a ring shaped projection extends outwardly from the surface of connector dowel 278 and facilitates correct positioning of connector dowel 278 in the coupling recess 282 of first pole section 230a and coupling recess 286 of second pole section 230b. Positioning projection 288 prevents connector dowel 278 from being pushed too far into either of coupling recess 282, 286, by engaging end face 274 of first pole section 230a or end face 276 of second pole section 230b. Positioning projection 288 may be a separate ring that is secured about connector dowel 278 or a ring manufactured integrally with connector dowel 278. Positioning projection 288 can, however, be omitted, if desired,

In Figure 16, it can be seen that coupling joint stabilization plate 268 is a disk with a centrally located aperture 290 through which connector dowel 278 extends. The inner diameter of coupling joint stabilization plate 268 is such that stabilization plate 268 rests on end face 276 of pole section 230b. A recess 292 is provided in a face of stabilization plate adjacent to aperture 290 to accommodate positioning projection 288.

Figure 17 is a cross sectional view of the assembled coupling joint and guy wire securement collar, taken at section line 17-17 in Figure 14. Positioning projection 288 on connector dowel 278 butts against end face 276 of second pole section 230b, and recess 292 in coupling joint stabilization plate 268 permits coupling joint stabilization plate 268 to fit over positioning projection 288 and fit closely against both first pole section 230a and second pole section 230b. Figure 17 also shows flanges 266 on guy collar half 258, and holes 270 provided therein to accommodate the bolts used to attach the two guy collar halves to each other. Connector dowel 278 fits closely within coupling recess 282 in pole section 230a and coupling recess 286 in pole section 230b, and may be friction fit, or secured with an adhesive 294, as shown here. Coupling recesses 282 and 286 may be continuous with and have the same diameter as the lumen of pole sections 230a and 230b, but this is not required. Connector dowel 278 may be formed of molded or extruded plastic, resin, or fiberglass, or it may be machined from metal such as aluminum. Any other material or manufacturing techniques which provide sufficient strength and durability may be used.

Figure 18 is an exploded view of the region at the top of utility transmission support 216 of Figure 13. End cap 240 is mounted to upper end 246 of pole section 230. End cap 240 has a conical outer surface 296 and a flat abutment surface 298 which fits against end face 300 of pole section 230. Conical outer surface 296 is sufficiently conical and pointed as to prevent birds from perching or nesting on the top of the pole. Abutment surface 298 is circular and of the same overall diameter as end face 300 of pole section 230 so as to cover end face 300. A projecting attachment peg 302 extends downwardly from abutment surface 298 and fits into lumen 304 which opens to the exterior of pole section 230 at upper end 246. Projecting attachment peg 302 is secured by a nut 311 and a throughbolt 306 that is passed through a hole 308 in upper end 246 of pole section 230 and a hole 310 in attachment peg 302. Alternatively, an adhesive can be used to secure attachment peg 302 in pole section end 246. Attachment peg 302 can be omitted, if abutment surface 298 of pole end cap 240 and pole section end 246 are simply fastened together using an adhesive. Mounting bracket 222 is made up of first and second mounting bracket halves 312 and 314, which are clamped to pole section 230 by nut 324 and throughbolt 316, which passes through hole 318 in first mounting bracket half 312, hole 320 in pole section 230, and hole 322 in second mounting bracket half 314. Inner surfaces 326 and 328 of mounting bracket halves 312 and 314, respectively, are curved to provide a surface fit with the exterior of pole section 230.

Cross arm 220 is clamped between first mounting bracket half 312 and locking plate 330. Groove 332 on the outer face of first mounting bracket half 312 and groove 334 on the inner face of locking plate 330 are shaped to receive cross arm 220 and hold it securely in place. Locking plate 330 is secured to mounting bracket 222 by nuts 342 and bolts 336 which pass through holes 338 in locking plate 330, through holes 340 in first mounting bracket half 312, and through holes 337 in said second mounting bracket half 314. Cross arm 220 is a two-layered structure having a cross section similar to that shown in Figure 10.

Figure 19 is a close-up view of an end 248 of cross arm 220 of Figure 13. Utility lines 244a and 244b are attached to eye bolts 344 and 346, respectively. The shafts of eye bolts 344 and 346 pass through holes in cross arm 220 and are secured with nuts 348 and 350, respectively. Connector wire 352 is a short length of wire that is attached to eye bolts 344 and 346 and provides an electrical connection between utility lines 244a and 244b. End 248 of cross arm 220 is also fitted with plug 242, which is secured in lumen 358 of cross arm 220 by press fitting or by an adhesive.

Figure 20 illustrates an alternative pole cap 360 that provides a platform for bird nesting. Pole cap 360 is beneficial to birds that prefer to build high nests in areas where there are few aerial nesting places available because of the paucity of trees. Pole cap 360 also helps prevent electrical service failures caused when a bird nest on the top of a utility pole droops downwardly onto electric wires. Pole cap 360 includes a platform base 362 and a projecting attachment peg 364. Attachment peg 364 is inserted into the lumen 366 of vertical support 368 and secured thereto with a nut 376 and a throughbolt 370 that is passed through a hole 372 in vertical support 368 and a hole 374 in attachment peg 364. Pole cap 360 may be provided with braces, not shown, to steady platform base 362 in high wind conditions.

Platform base 362 includes a vertical wall 378 extending along some or all of the periphery of platform base 362. Vertical wall 378 retains nest materials on platform base 362 and prevents such materials from hanging down onto utility wires carried by vertical support 368. Platform base 362 is provided with weep holes 380 to allow rain water to drain out. The central region 382 of platform base 362 overlying vertical support 368 is free of weep holes to prevent the drainage of water into lumen 366 at the interior of vertical support 368.

The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all

Claims

respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. What is claimed is:

1. An elongated support structure comprising:

(a) an elongated core formed of a substantially homogenous composite material; and

(b) a reinforcing layer bonded to the outer surface of said core, said reinforcing layer comprising:

(i) binding resin; and

(ii) reinforcing fibers embedded in said binding resin.

2. A support structure as recited in Claim 1 , wherein said core has a circular outer cross section.

3. A support structure as recited in Claim 1, wherein said core has a noncircular outer cross section.

4. A support structure as recited in Claim 3, wherein said core has a square outer cross section.

5. A support structure as recited in Claim 1 , wherein said composite material comprises: (a) a matrix resin; and

(b) a strengthening material of fine, elongated particles.

6. A support structure as recited in Claim 5, wherein said strengthening material comprises a material from the group consisting of wood fibers, chopped fiberglass, polymer fibers, and carbon fibers.

7. A support structure as recited in Claim 5, wherein said strengthening material comprises wood fibers.

8. A support structure as recited in Claim 5, wherein said matrix resin is phenolic resin.

9. A support structure as recited in Claim 5, wherein said matrix resin is polymeric resin.

10. A support structure as recited in Claim 5, wherein said matrix resin is water borne.

11. A support structure as recited in Claim 5, wherein said matrix resin is catalyst cured.

12. A support structure as recited in Claim 5, wherein said matrix resin is thermoset cured.

13. A support structure as recited in Claim 5, wherein said composite material further comprises an additive from the group consisting of ultraviolet inhibitors, insect repellants, and colorants.

14. A support structure as recited in Claim 1, further comprising climb facilitation means on the exterior of said reinforcing layer for receiving climbing spikes.

15. A support structure as recited in Claim 14, wherein said climb facilitation means comprises a climbing layer of expanded foam bonded to the outer surface of said reinforcing layer, said climbing layer having a combination of density and strength sufficient to support a worker and the equipment thereof.

16. A support structure as recited in Claim 15, wherein said climbing layer comprises a rough outer surface, thereby affording enhanced frictional purchase on the exterior of said elongated support structure.

17. A support structure as recited in Claim 11 , wherein said core is hollow, the interior of said core thereby defining a centrally disposed lumen longitudinally extending between opposite first and second ends of said core, said lumen opening to the exterior of said core at said first end thereof.

18. A support structure as recited in Claim 17, further comprising an end cap attached to said support structure at an end thereof corresponding to said first end of said core, said end cap sealing said lumen in said core from the exterior of said support structure.

19. A support structure as recited in Claim 18, wherein said end cap comprises a projecting attachment peg received in said lumen at said first end of said core.

20. A support structure as recited in Claim 18, further comprising a platform secured to said end cap remote from said core of said support structure.

21. A support structure as recited in Claim 17, wherein said lumen opens to the exterior of said core at said second end thereof.

22. A support structure as recited in Claim 21, further comprising an end cap attached to said support structure at an end thereof corresponding to said second end of said core, said end cap sealing said lumen in said core from the exterior of said support structure.

23. A support structure as recited in Claim 22, wherein said end cap comprises a projecting attachment peg received in said lumen at said second end of said core.

24. A support structure as recited in Claim 22, further comprising a footing secured to said end cap remote from said core of said support structure.

25. An elongated support structure comprising:

(a) an elongated hollow core formed of a substantially homogeneous composite material, said composite material comprising:

(i) a matrix resin; and (ii) a strengthening material of fine, substantially elongated particles; and

(b) a reinforcing layer bonded to the outer surface of said core.

26. A support structure as recited in Claim 25, wherein said reinforcing layer comprises:

(a) a binding resin; and

(b) reinforcing fibers embedded in said binding resin.

27. A support structure as recited in Claim 26, wherein said reinforcing fibers comprise fiberglass roving.

28. A support structure as recited in Claim 26, wherein said reinforcing fibers comprise fiberglass matting.

29. A support structure as recited in Claim 26, wherein said reinforcing fibers comprise spirally wound fibers.

30. A support structure as recited in Claim 26, wherein said reinforcing fibers comprise surfacing veil.

31. A support structure as recited in Claim 26, wherein said binding resin is identical to said matrix resin.

32. A support structure as recited in Claim 26, wherein said binding resin is phenolic resin.

33. A support structure as recited in Claim 26, wherein said binding resin is polymeric resin.

34. A support structure as recited in Claim 26, wherein said binding resin is water borne.

35. A support structure as recited in Claim 26, wherein said binding resin is thermoset cured.

36. A support structure as recited in Claim 26, wherein said binding resin is catalyst cured.

37. A support structure as recited in Claim 26, further comprising climb facilitation means on the exterior of said reinforcing layer for receiving climbing spikes.

38. A utility pole comprising:

(a) an elongated support structure suitable for outdoor use in a generally vertical orientation, said support structure comprising: (i) an elongated core formed of a substantially homogeneous composite material comprising: a) a matrix resin; and b) a strengthening material of fine, elongated particles; and (ii) a reinforcing layer bonded to the outer surface of said core, said reinforcing layer comprising: a) a binding resin; and b) reinforcing fibers embedded in said binding resin; and (b) a cross arm fixed to said support structure in a nonvertical orientation.

39. A utility pole as recited in Claim 38 , further comprising a mounting bracket fixing said cross arm to said support structure.

40. A utility pole as recited in Claim 39, further comprising hardware capable of securing an electrical line to said cross arm.

41. A utility pole as recited in Claim 40, wherein said hardware comprises a clamp attachable to said cross arm with the electrical line engaged between said clamp and said cross arm.

42. A utility pole as recited in Claim 40, wherein said hardware comprises an eye bolt secured to said cross arm, said eye bolt having a hoop sized to receive the electrical line.

43. A utility pole as recited in Claim 38, further comprising an end cap attached to an end of said support structure, said end cap comprising:

(a) an abutment surface engaging said end of said support structure; and

(b) an outer surface presented to the environment in which said utility pole is installed.

44. A utility pole as recited in Claim 43, wherein said outer surface of said end cap comprises a conical surface.

45. A utility pole as recited in Claim 43 , wherein said outer surface of said end cap comprises a semispherical surface.

46. A utility pole as recited in Claim 43 , further comprising a platform secured to said outer surface of said end cap.

47. A utility pole as recited in Claim 43, further comprising a footing secured to said outer surface of said end cap.

48. A utility pole as recited in Claim 38, wherein said support structure further comprises a climbing layer of expanded foam bonded to the outer surface of said reinforcing layer.

49. An elongated support structure for outdoor use, the support structure being of the type capable of erection vertically or horizontally bearing signs, cross arms, railings, power lines, or other loads mounted thereto, said support structure comprising:

(a) an elongated core formed of a substantially homogeneous composite material comprising:

(i) matrix resin; and

(ii) strengthening material of fine, elongated particles; and

(b) a reinforcing layer bonded to the outer surface of said core, said reinforcing layer comprising: (i) binding resin; and

(ii) reinforcing fibers embedded in said binding resin.

50. A support structure as recited in Claim 49, wherein said strengthening material comprises wood fibers.

51. A support structure as recited in Claim 49, wherein said core is hollow, the interior of said core thereby defining a longitudinally extending lumen with an open end.

52. A support structure as recited in Claim 51 , wherein said lumen is divided into longitudinal compartments by a structural divider.

53. A support structure as recited in Claim 49, wherein said binding resin is identical to said matrix resin.

54. A support structure as recited in Claim 51 , wherein said core has a circular outer cross section.

55. A support structure as recited in Claim 51, wherein said core has a hexagonal outer cross section.

56. A support structure as recited in Claim 51 , wherein said core has a square outer cross section.

57. An elongated support structure comprising:

(a) an elongated core;

(b) a reinforcing layer bonded to the outer surface of said core, said reinforcing layer comprising: (i) resin; and

(ii) reinforcing fibers embedded in said resin; and

(c) a climbing layer of expanded foam bonded to the outer surface of said reinforcing layer.

58. A support structure as recited in Claim 57, wherein said climbing layer is comprised of a resin selected from the group consisting of polyurethane, polyvinylchloride, polypropylene and synthetic rubber.

59. A support structure as recited in Claim 57, wherein said climbing layer has a density of between about 1-30 pounds per cubic foot.

60. A support structure as recited in Claim 59, wherein said climbing layer has a density of between about 2-25 pounds per cubic foot.

61. A support structure as recited in Claim 60, wherein said climbing layer has a density of between about 3-15 pounds per cubic foot.

62. A support structure as recited in Claim 57, wherein said core is hollow, the interior of said core thereby defining a longitudinally extending lumen with an open end.

63. A support structure as recited in Claim 62, wherein said lumen is divided into longitudinal compartments by a structural divider.

64. A support structure as recited in Claim 63, wherein said structural divider is integral with said core.

65. A support structure as recited in Claim 63, wherein said structural divider has an X-shaped cross section in a plane perpendicular to the longitudinal axis of said core.

66. A support structure as recited in Claim 65, wherein said X-shaped cross section comprises spokes radiating outward from a central hub.

67. A support structure as recited in Claim 66, wherein said hub comprises a centrally located opening.

68. A support structure as recited in Claim 63, wherein said structural divider has a Y-shaped cross section in a plane perpendicular to the longitudinal axis of said core.

69. A support structure as recited in Claim 63, wherein the cross section of said structural divider taken in a plane perpendicular to the longitudinal axis of said core, comprises:

(a) an annulus; and

(b) a spoke extending radially outward from the exterior of said annulus to said interior of said core.

70. A support structure as recited in Claim 63, wherein said structural divider comprises:

(a) an elongated cylindrical element positioned in coaxial relationship with said core; and

(b) an elongated, longitudinally extending fin connected along a first longitudinal edge thereof to the exterior of said elongated cylindrical element and connected on a second parallel longitudinal edge to said interior of said core.

71. A support structure as recited in Claim 63, wherein the cross section of said structural divider taken in a plane peφendicular to the longitudinal axis of said core, comprises:

(a) a hexagon; and (b) a spoke extending radially outward from each respective vertex of said hexagon to said interior of said core.

72. A support structure as recited in Claim 71 , wherein said hexagon comprises a centrally located opening.

73. An elongated support structure for outdoor use, the support structure being of the type capable of erection vertically or horizontally for bearing signs, cross arms, railings, power lines, or other loads mounted thereto, said support structure comprising:

(a) an elongated structural member; and (b) a climbing layer of expanded foam bonded to the outer surface of said elongated structural member.

74. An elongated support structure as recited in Claim 73, wherein said expanded foam comprises polyurethane.

75. An elongated support structure as recited in Claim 74, wherein said expanded foam has a density of between about 1-30 pounds per cubic foot.

76. An elongated support structure as recited in Claim 74, wherein said expanded foam has a density of between about 2-25 pounds per cubic foot.

77. An elongated support structure as recited in Claim 74, wherein said expanded foam has a density of between about 3-15 pounds per cubic foot.

78. An elongated support structure as recited in Claim 73, wherein said expanded foam encircles said outer surface of said elongated structural member.

79. A mixture from which to form a core of a support structure, said mixture comprising:

(a) a matrix resin; and

(b) fibrous material intermixed with said resin, said fibrous material consisting essentially of fibers being of a length in the range of about 0.50 - 4.00 inches.

80. A mixture as recited in Claim 79, wherein said fibrous material consists essentially of fibers being of a length in the range of about 0.75 - 2.0 inches.

81. A mixture as recited in Claim 79, wherein said resin is phenolic resin.

82. A mixture as recited in Claim 79, wherein said resin is polymeric resin.

83. A mixture as recited in Claim 79, wherein said resin is water borne.

84. A mixture as recited in Claim 79, wherein said resin is catalyst cured.

85. A mixture as recited in Claim 79, wherein said resin is thermoset.

86. A mixture as recited in Claim 79, wherein said mixture further comprises an additive from the group consisting of ultraviolet inhibitors, insect repellants, and colorants.

87. A mixture as recited in Claim 79, wherein said fibrous material comprises a material from the group consisting of wood shreds, coconut husks, palm bark, hemp, sisal, bagasse, and tree fibers.

88. A mixture as recited in Claim 79, wherein said fibrous material comprises wood shreds from which substantially all moisture, resins, and sap have been removed.

89. A mixture as recited in Claim 88, wherein said fibrous material comprises wood shreds from which at least 99 percent of the moisture, resins, and sap have been removed.

90. A mixture as recited in Claim 79, wherein said fibrous material comprises from about 50 to about 85 percent of the total volume of said mixture.

91. A mixture as recited in Claim 79, wherein said fibrous material comprises from about 65 to about 75 percent of the total volume of said mixture.

92. A method for manufacturing an elongated support structure, said method comprising the steps:

(a) extruding a substantially homogeneous mixture into an elongated core, said mixture comprising: (i) a matrix resin; and

(ii) a strengthening material of fine, elongated particles intermixed with said matrix resin; and

(b) applying a reinforcing layer to the exterior of said core, said reinforcing layer comprising: (i) a binding resin; and

(ii) reinforcing fibers embedded in said binding resin.

93. A method as recited in Claim 92, wherein said step of applying comprises the steps: (a) shaping the exterior of said reinforcing layer in a continuous feed die; and

(b) curing said reinforcing layer using heat.

94. A method as recited in Claim 93, wherein said die is adjustable.

95. A method as recited in Claim 93, wherein in said step of curing, said heat is externally applied.

96. A method as recited in Claim 93, wherein in said step of curing, said heat is generated by a catalyst.

97. A method as recited in Claim 93, further comprising the step of forming a layer of expanded foam on the exterior of said reinforcing layer.

98. A method for manufacturing a climbable elongated support structure, said method comprising the steps:

(a) providing an elongated structural member; and (b) bonding a layer of expanded foam to the exterior of said elongated structural member.

99. A method as recited in Claim 98, wherein said step of bonding comprises the step of forming a layer of expanded foam directly against the exterior of said elongated structural member.

100. A method as recited in Claim 99, wherein said step of forming comprises the steps:

(a) introducing into a foam expansion chamber a resin and a foaming agent thereby, producing foamed resin in said foam expansion chamber;

(b) expanding said foamed resin to fill said foam expansion chamber; and

(c) advancing said elongated structural member longitudinally through said foam expansion chamber, adhering a layer of said foamed resin to the exterior of said elongated structural member.

101. A method as recited in Claim 100, wherein said step of forming further comprises the steps:

(a) shaping the exterior of said layer of foamed resin; and (b) curing said layer of foamed resin.

102. A method as recited in Claim 98, wherein said bonding step comprises bonding a preformed expanded foam layer to the exterior of said elongated structural member.

103. An elongated support structure comprising

(a) first and second pole sections interconnected in aligned end-to-end relationship to form a coupling joint therebetween, each of said pole sections comprising:

(i) an elongated core;

(ii) a reinforcing layer bonded to the outer surface of said elongated core, said reinforcing layer comprising: a) resin; and b) reinforcing fibers embedded in said resin;

(iii) an end face circumscribed by the exterior of said reinforcing layer at the end of said pole section at said coupling joint; and (iv) a coupling recess formed in said end face; and

(b) means for securing said first and second pole sections at said coupling joint in said end-to-end relationship.

104. An elongated support structure as recited in Claim 102, wherein said means for securing comprises a connector dowel traversing said coupling joint, said connector dowel comprising:

(a) a first end received in said coupling recess in said end face of said first pole section end; and

(b) a second end received in said coupling recess in said end face of said second pole section.

105. A pole as recited in Claim 104, wherein said connector dowel is secured with an adhesive in said coupling recess of said first and second pole section, respectively.

106. An elongated support structure as recited in Claim 104, wherein said means for securing further comprises a coupling joint stabilization plate having a centrally located aperture, said stabilization plate being engaged on the opposite sides thereof by said end face of said first pole section and second pole section, respectively, with a medial portion of said connecting dowel extending through said aperture in said stabilization plate.

107. An elongated support structure as recited in Claim 106, wherein said stabilization plate is a disc, and said aperture thereof is concentric therewith.

108. An elongated support structure as recited in Claim 106, wherein the periphery of said stabilization plate projects radially outwardly at said coupling joint of the exterior of said first and second pole sections, respectively.

109. An elongated support structure as recited in Claim 108, further comprising a guy wire securement collar encircling said outer surface of said first pole section immediately adjacent to and engaging of a side of said stabilization plate between said outer surface of said first pole section and said periphery of said stabilization plate.

110. An elongated support structure comprising: (a) first and second pole sections interconnected in aligned end-to-end relationship to form a coupling joint therebetween, each of said pole sections comprising:

(i) an end face at the end of each of said pole sections at said coupling joint; and (ii) a coupling recess formed in said end face; and

(b) a connector dowel traversing said coupling joint and having:

(i) a first end received in said coupling recess in said end face of said first pole section; and

(ii) a second end received in said end face of said second pole section.

111. An elongated support structure as recited in Claim 110, wherein said connector dowel further comprises a positioning projection extending radially outward from said connector dowel between said first end and said second end, said positioning projection engaging with said end face of said first pole section to determine the positioning of said connector dowel within said first pole section.

112. An elongated support structure as recited in Claim 111, wherein said positioning projection comprises a ring-shaped projection about the circumference of said connector dowel.

113. An elongated support structure as recited in Claim 110, wherein said connector dowel comprises metal.

114. An elongated support structure as recited in Claim 110, wherein each of said first and second pole sections is hollow, the interior of each of said first and second pole sections defining a corresponding longitudinally extending lumen, each of said lumens communicating with the exterior of a respective of said pole sections by way of said coupling recess therein.

115. An elongated support structure as recited in Claim 110, wherein each of said first and second pole sections comprises:

(a) an elongated core; and

(b) a reinforcing layer bonded to the outer surface of said elongated core, said reinforcing layer comprising: (i) resin; and

(ii) reinforcing fibers embedded in said resin.

116. An elongated support structure comprising

(i) an elongated core formed of a substantially homogenous composite material, said composite material comprising: a) a matrix resin; and b) a strengthening material of fine, elongated particles; (ii) a reinforcing layer bonded to the outer surface of said elongated core, said reinforcing layer comprising: a) a binding resin; and b) reinforcing fibers embedded in said binding resin; (iii) an end face circumscribed by the exterior of said reinforcing layer at the end of said pole section at said coupling joint; and (iv) a coupling recess formed in said end face; and (b) means for securing said first and second pole sections at said coupling joint in said end-to-end relationship.

117. An elongated support structure as recited in Claim 116, wherein said means for securing comprises a connector dowel traversing said coupling joint, said connector dowel comprising:

118. An elongated support structure as recited in Claim 117, wherein said means for securing further comprises a coupling joint stabilization plate having a centrally located aperture, said stabilization plate being engaged on the opposite sides thereof by said end face of said first pole section and second pole section, respectively, with a medial portion of said connecting dowel extending through said aperture in said stabilization plate.

119. An elongated support structure as recited in Claim 117, wherein said connector dowel further comprises a positioning projection extending radially outward from said connector dowel between said first end and said second end, said positioning projection engaging with said end face of said first pole section to determine the positioning of said connector dowel within said first pole section.

120. An elongated support structure as recited in Claim 119, wherein said positioning projection comprises a ring-shaped projection about the circumference of said connector dowel.

121. An elongated support structure as recited in Claim 116, wherein each of said first and second pole sections is hollow, the interior of each of said pole sections defining a corresponding longitudinally extending lumen, said lumen communicating with the exterior of said pole section by way of said coupling recess.

122. An elongated support structure as recited in Claim 116, further comprising climb facilitation means on the exterior of said reinforcing layer for receiving climbing spikes.

123. An elongated support structure as recited in Claim 122, wherein said climb facilitation means comprises a climbing layer of expanded foam resin bonded to the outer surface of said reinforcing layer, said climbing layer having a combination of density and strength sufficient to support a worker and the equipment thereof.