Electrical insulator apparatus and methods of retaining an electrical conductor with an electrical insulator apparatus

An electrical insulator apparatus and methods of using the same are provided. The apparatus includes an insulator body formed about a central axis, the insulator body having a plurality of spaced fins positioned along an exterior of the insulator body. A first jaw portion is positioned on an upper portion of the insulator body. A second jaw portion is positioned proximate to the first jaw portion and is movable with respect to the first jaw portion. At least one fastener is connected between the first and second jaw portions. A jaw platform is positioned at least partially between the first and second jaw portions, wherein the first and second jaw portions and the jaw platform form a notch sized to receive an electrical conductor, wherein the jaw platform substantially lies within a first plane angled substantially between 6° and 184° with respect to the central axis of the insulator body.

FIELD OF THE DISCLOSURE

The present disclosure is generally related to overhead distribution and transmission insulators and more particularly is related to electrical insulator apparatus and methods of retaining an electrical conductor with an electrical insulator apparatus.

BACKGROUND OF THE DISCLOSURE

Insulators are used with electrical transmission and distribution systems to isolate and support electrical conductors above the ground for overhead power distribution and transmission. Tie-wire and clamping mechanisms are used to secure and hold electrical conductors that are strung between utility poles in a variety of common configurations, such as roadside (tangent) or road crossing (angled) spans between the utility poles. For tangent and small angle configurations, typically up to 5°, the electrical conductors are supported on the top portion of the insulator, known as the top saddle. On angled configurations, typically greater than 5°, the electrical conductors are supported on the side portion of the insulator, known as the neck or side saddle. For the most part these needs have been met by use of a tie-wire, a pre-formed tie-wire, a clamp-top fitting, or an integral vise-top.

Tie-wire is a low-cost material, but may not achieve the desired conductor grip strength due to variation in hand-tying methods by installation personnel. It may also lack consistency in grip strength from one location to the next although the same tying method is utilized. Another deficiency of tie-wire is the required method of wrapping the wire about the neck of the insulator effectively reduces the electrical resistance path to ground. Preformed tie-wire overcomes the tie-wire deficiency in strength and consistency, but shares the issue of reducing the resistance path to ground. Preformed tie-wires carry a higher per unit cost and also require several different models to accommodate the wide range of conductor sizes and configurations used in the field.

Clamp-top fittings typically consist of a metal bracket for attachment to the insulator neck and an additional metallic assembly to keep and clamp the conductor. Clamp-top fittings generally accept a wide range of conductor sizes, but still require multiple models to cover the full range of conductor sizes and insulator neck sizes. There is a high per unit cost and a high installation cost when compared to ties. Their top saddle position also raises the conductor some distance (e.g. 3-inch) above the normal conductor mounting position which can increase the moment (force) applied to mounting hardware in small angle configurations. This has the drawback of forcing the user to shift the installation to a side-saddle position, with an associated reduction in resistance path to ground and dry-arc distance, for small angles that would otherwise be accommodated in the top saddle position by tie-wire methods.

Vise-top insulators are generally formed on insulator bodies having opposing jaws positioned at the top of the insulator body. The opposing jaws include at least one jaw piece that is adjustable relative to the other jaw piece, such that the jaw pieces can be clamped on an electrical conductor therebetween and retain it in place. Vise-top insulators overcome many of the deficiencies cited for devices above by accommodating a wide range of conductor sizes in a single model. However, the conductor grip strength is generally less than that of preformed ties and clamp-top fittings.

There has long been a need to reliably and economically secure a wide range of electrical conductor sizes to the insulator. Conventional insulators and associated ties or clamps, as cited above, generally accommodate the reliability aspects of tangent configurations. However, for angled configurations typically greater than 5° the electrical conductors are supported on the side saddle and these conventional insulators often are unable to provide the necessary mechanical and electrical support to ensure safe and proper functioning of the electrical conductor over the expected lifetime. They are also unable to provide the flexibility within one device to accommodate the wide range of conductor sizes, types, configurations and grip strength requirements.

SUMMARY OF THE DISCLOSURE

Embodiments of the present disclosure provide an electrical insulator apparatus. Briefly described, in architecture, one embodiment of the apparatus, among others, can be implemented as follows. An insulator body is formed about a central axis, the insulator body having an internal cavity and a plurality of spaced fins positioned along an exterior of the insulator body. A first jaw portion is positioned on the insulator body. A second jaw portion is connected to the first jaw portion. At least one fastener is connected between the first and second jaw portions. A jaw platform has a platform surface, wherein the platform surface is formed at least partially between the first and second jaw portions, and wherein a plane substantially aligned with the platform surface intersects the internal cavity.

The present disclosure can also be viewed as providing an electrical insulator apparatus for side-saddle mounting of a conductor. Briefly described, in architecture, one embodiment of the apparatus, among others, can be implemented as follows. An insulator body is formed about a central axis, the insulator body having an threaded internal cavity sized to receive a mounting pin. A plurality of spaced fins is positioned radially about the threaded internal cavity along an exterior of the insulator body. A first jaw portion is formed integral with the insulator body. A second jaw portion is movably engaged to the first jaw portion. A jaw platform is formed between the first and second jaw portions and having a substantially planar platform surface, wherein the first jaw portion, the second jaw portion, and the jaw platform form a conductor-receiving notch, and wherein a plane substantially aligned with the substantially planar platform surface intersects the internal cavity. A first threaded fastener is engaged between the first and second jaw portions in a position above the substantially planar platform surface. A second threaded fastener is engaged between the first and second jaw portions in a position below the substantially planar platform surface.

The present disclosure can also be viewed as providing methods of retaining an electrical conductor with an electrical insulator apparatus. In this regard, one embodiment of such a method, among others, can be broadly summarized by the following steps: securing the electrical insulator apparatus to a utility fixture, wherein a pin affixed to the utility fixture engages with an internal cavity of an insulator body of the electrical insulator apparatus; and retaining a portion of the electrical conductor within a receiving notch formed on the insulator body between a first jaw portion, a second jaw portion, and a jaw platform, wherein the portion of the electrical conductor contacts a platform surface of the notch, wherein a plane of a platform surface of the jaw platform is aligned to intersect the internal cavity, wherein the portion of the electrical conductor applies a longitudinal force against the pin within the cavity.

DETAILED DESCRIPTION

FIG. 1is a cross-sectional illustration of an electrical insulator apparatus10, in accordance with a first exemplary embodiment of the present disclosure. The electrical insulator apparatus10, which may be referred to simply as ‘apparatus10,’ includes an insulator body20formed about a central axis22, the insulator body20having an internal cavity24and a plurality of spaced fins26positioned along an exterior of the insulator body20. A first jaw portion40is positioned on the insulator body20. A second jaw portion50is connected to the first jaw portion40. At least one fastener60is connected between the first and second jaw portions40,50. A jaw platform70has a platform surface72, wherein the platform surface72is formed at least partially between the first and second jaw portions40,50, and wherein a plane74substantially aligned with the platform surface72intersects the internal cavity24.

The apparatus10may be used to retain electrical conductors, which are used in systems for the transmission and distribution of electrical power. The apparatus10may be used to both install and retain electrical conductors along various electrical fixtures, such as utility poles, towers, or other fixtures. The apparatus10may be affixed or fastened to any part of the utility fixture, such as to a cross member of the utility fixture. The apparatus10may be used in conjunction with any number of other devices that are known and available within the art, and it should be appreciated that other variations beyond this disclosure are also possible. In particular,FIG. 1illustrates a pin type insulator, but this disclosure can apply to other insulator types, such as line post insulators or similar types of insulator constructions.

The insulator body20is used to isolate electrical conductors from a utility fixture. The insulator body20is formed about the central axis22, such that the central axis22is positioned approximately through the center point of the insulator body20. In other words, the central axis22may be characterized as running along a length of the insulator body20, such that is traverses through the ends of the insulator body20. The insulator body20may be constructed from a variety of different materials that are commonly known and readily available within the art. The size of the insulator body20may vary depending on the size or voltage rating of the electrical conductor that it is designed to retain.

The internal cavity24of the insulator body20may be sized to engage with a mounting pin (not shown) which is affixed to a utility structure, such as a cross-arm of a utility pole. The internal cavity24may have varying diameters along its length and any portion thereof may have internal threading for engagement with external threads of a mounting pin. While the internal cavity24may have different lengths relative to the insulator body20, it may commonly traverse into the insulator body20past the spaced fins26and in to an upper portion of the insulator body20, terminating at a position proximate to the first jaw portion40. The insulator body20may include any number of spaced fins26positioned thereon in a variety of configurations. The number or size of the plurality of spaced fins26may vary depending on the design of the insulator body20. For example, the insulator body20may have one, two, or three or more fins26radially positioned about the insulator body20and spaced relative to one another. The size of the fin26, in particular, the distance from the tip of the fin26to its center, may vary between the fins26on the insulator body20.

The first jaw portion40, second jaw portion50, and jaw platform70may collectively form a notch for receiving the electrical conductor, and are used to secure the electrical conductor to the insulator body20. The notch formed by the first jaw portion40, second jaw portion50, and jaw platform70is positioned on an upper portion or upper area of the insulator body20. While a lower portion or lower area of the insulator body20may be affixed to a utility fixture via a mounting pin. The first jaw portion40may be positioned removably to or integral with the upper portion of the insulator body20. Similarly, the second jaw portion50may be connected to the first jaw portion40with a fixed connection or a movable connection. Commonly, the second jaw portion50is movably connected to the first jaw portion40, thereby allowing the second jaw portion50to provide a clamping function relative to the first jaw portion40, allowing for the electrical conductor to be clamped between the first and second jaw portions40,50.

The jaw platform70is formed between the first and second jaw portions40,50, and has a platform surface72as a base surface on which an electrical conductor can be placed. In this configuration, the electrical conductor can be secured between the first and second jaw portions40,50, and the platform surface72of the jaw platform70. The platform surface72may be a substantially planar surface, such that it is substantially formed along the plane74. It is noted that the substantially planar surface may include a number of features that are not planar, such as a textured surface, a slight curvature, or other features, none of which detract from the general positioning of the platform surface72along the plane74.

The at least one fastener60is connected between the first and second jaw portions40,50. The fastener60may include a threaded fastener that is threadedly engaged with a threaded hole42positioned within at least one of the first jaw portion40and the second jaw portion50. InFIG. 1, the fastener60is shown being connected between the first and second jaw portions40,50and threadedly connected within the threaded hole42within the first jaw portion40. It may be common for more than one fastener60be used, such as, for example, with one fastener60connected between the first and second jaw portions40,50above the platform surface72and another fastener60connected between the first and second jaw portions40,50below the platform surface72. The fastener60or fasteners60may secure the first and second jaw portions40,50in a closed position, or retain them in an open position. Thus, the fastener60may control the spacing between the second jaw portion50and the first jaw portion40. For a threaded fastener, when it is rotated, the threads on the end of the fastener60in combination with the threaded hole42will draw the second jaw portion50towards the first jaw portion40. As is known in the art, it may be preferable for threading on the fasteners to be unique to electrical insulating devices, such as this apparatus10, to prevent the use of common threaded metallic fasteners, which may harm an electrical conductor within the notch.

As is shown inFIG. 1, the first jaw portion40may be formed integrally with the insulator body20at an upper portion of the insulator body20. The first jaw portion40has a contact face44, opposing the second jaw portion50, which may be contacted by the electrical conductor when it is positioned within the notch. The contact face44may extend to the platform surface72of the jaw platform70, and may be formed integral with the jaw platform70. The contact face44may have any size or dimension. Furthermore, as is discussed relative toFIGS. 2-4D, the contact face44may support a liner material for increasing frictional contact between the first jaw portion40and the electrical conductor.

The second jaw portion50may have a hole52therein which the threaded fastener60can engage with or traverse through. The hole52may be aligned with the hole42of the first jaw portion40. A contact face54of the second jaw portion50may oppose the contact face44of the first jaw portion40, and may extend towards the platform surface72. When the second jaw portion50is fixed to the jaw platform70, the contact face54of the second jaw portion50may be formed integral with the jaw platform70. When the second jaw portion50is movable relative to the first jaw portion40or the jaw platform70, the contact face54may terminate proximate to the platform surface72. As is described further relative to other figures of this disclosure, while the second jaw portion50may connect to the first jaw portion40with the threaded fastener60, it may also slidably engage with the jaw platform70.

The platform surface72positioned along the plane74may be formed at an angle with respect to the insulator body20and the central axis22. The central axis22intersects the plane74at the upper portion of the insulator body20. The intersection of the central axis22and the plane74may be a perpendicular or angled, depending on the design of the apparatus. As is shown inFIG. 1, the angle between the central axis22and the plane74is identified with reference character θ. In accordance with this disclosure, the angle θ between the central axis22and the plane74may be measured on the angle formed therebetween.FIG. 1depicts the angle θ as being substantially perpendicular while other figures of this disclose depict the angle θ as being non-perpendicular.

When the apparatus10is positioned to hold an electrical conductor that is being strung along a curve or a bend in the electrical conductor path, the electrical conductor may also produce lateral forces exerted on the first and second jaw portions40,50, and the jaw platform70. For this angled construction, the electrical conductor's horizontal tensions on each side of the insulator body20induce a horizontal cantilever force. The plane74that is substantially aligned with the platform surface72intersects the internal cavity24within the insulator body20. The proximity and the level positioning of the platform surface72of the jaw platform70with respect to the internal cavity24may reduce detrimental moment and any long term creep. By positioning the plane74of the platform surface72to intersect the internal cavity24, the cantilever force of the electrical conductor may be fully absorbed by the mounting pin (FIG. 6), where the deflection resistance of the pin material under cantilever force is the limiting factor, not the deflection resistance of the insulator body20itself. When line post insulators (not shown), or similar insulators, are used, the plane72of the platform surface72may intersect a strength member positioned within the internal cavity24. The strength member may include a central fiberglass rod or similar structure that helps absorb the cantilever force of the electrical conductor, similar to a mounting pin positioned within the internal cavity24.

The apparatus10may provide significant benefits in retaining electrical conductors along angled paths by allowing the lateral forces created by the electrical conductor to be transferred primarily to the mounting pin within the internal cavity24. When the platform surface72is angled relative to the central axis22, as is discussed relative toFIGS. 8-10Bthe apparatus may provide even more support for properly retaining the electrical conductor in an angled path. It is noted, however, that the apparatus10can be successfully used in both angled and non-angle or tangential conductor paths, which allows a single device to be used for most conductor mounting situations. The ability to use a single device provides significant benefits over the prior art, which require specific mounting devices to be used for tangential portions of a conductor path, and other mounting devices to be used for angled portions of a conductor path.

Examples of using the apparatus10relative to the requirements of industry standards are provided. As an electrical conductor is held by the apparatus10, the weight of the electrical conductor will create a downward force, generally directed centrally to the jaw platform70. The alignment of the plane74of the platform surface72with the internal cavity24is a primary factor when analyzing the acting conductor loads. In a tangent construction and a steady state, the only load acting on the platform is the conductor's weight. Due to the close proximity of the platform surface72to the central axis22, the moment induced by this vertical load is extremely small and has no impact during the lifetime of the insulator.

The following load calculation for a tangent construction is provided as means of clarification. A large conductor and Heavy Loading Zone conditions, in accordance with National Electrical Safety Code (NESC), are applied for the calculation:

Vertical load (Lv) is given by the formula:
LV=Total Linear Weight×Span
LV=2.28×250=570 lbf
Thus, the acting vertical load upon the apparatus10is approximately 600 lbf for a Heavy Loading Zone condition of a tangent configuration.

Common mounting pins, such as Joslyn Catalog No J606Z, J203Z & J207Z, may be used to install the apparatus10on the utility fixture. Finite Element Analysis (FEA) may be used to simulate the acting force on the mounting pin and the resultant deflection. FEA with cast steel key mechanical properties, representative of the described mounting pins, shows that for a vertical load of 600 lbf and a standard 6″ mounting pin, a deflection angle of 0.86° may occur, which is significantly less than the 10° deflection allowed by industry design practice.

This example considers the compliance with the National Electrical Safety Code (NESC) Section 27, table 277-1 “Allowed percentages of strength rating” for insulators, where the maximum allowed service load acting on the insulator is 40% of its published rated value. Within the industry, the bending strength is typically rated to 3000 lbf, hence the 40% NESC allowance computes to 1200 lbf maximum permissible service load. The same FEA analysis as in Example 1 shows that for a vertical load of 1200 lbf, a corresponding mounting pin deflection angle of 1.75° may occur.

In another example, the most stringent case is compliance with the State of California General Order GO 95, Rule 44.1 Table 4 “Minimum Safety Factor” for Grade of Construction “A”. The minimum safety factor for Line insulators' mechanical loads for Grade “A” is to be 3. The vertical load to consider is then the actual load in Example 1 multiplied by the safety factor which computes to approximately 1800 lbf. The FEA simulation performed as in Example 1 shows that a pin deflection angle of 2.67° may occur which is considerably less than the 10° deflection that is allowed by industry design practice.

Considering the same Heavy Loading Zone conditions in the previous examples with the additional condition of 40 mile/hour wind and fixing the maximum mounting pin permissible deflection to 10°, the maximum allowable Line Angle for an angled construction is calculated for common conductor sizes as follows:

These calculations show that large line angle configurations for heavy loading conditions are possible with the present disclosure. The mechanical strength and the size of the mounting pin are the limiting factors. Increasing the diameter or choosing a higher Young's modulus for a metal pin will thus increase the permissible line angle while still satisfying the 10° maximum pin deflection limitation.

As a point of comparison to the present disclosure, conventional insulators within the industry support the electrical conductor in a top-saddle position for tangent, small angle configurations, e.g., less than 5°, or configurations with lateral wind forces. The top saddle is centered at some distance above the mounting pin, typically 0.50 inch or more, and the additional wind load component and related conductor blow angle cause a resultant moment and a mounting pin deflection angle larger than that of the present disclosure. The allowable line angle values in the above example exceed the allowable angles calculated for conventional insulators supporting the electrical conductor in a top-saddle. When conventional insulators are used for angled configurations, e.g., greater than 5°, the conductor is commonly placed in a side-saddle position. Similar to the top-saddle position, this side-saddle position in conventional insulators is positioned a distance above the mounting pin. The lateral force of the conductor applied to the conventional insulator above the mounting pin substantially increases the cantilever forces applied to the conventional insulator to undesirable levels. Furthermore, the side-saddle position places the electrical conductor closer in proximity to the utility fixture, when compared to its top-saddle position, and therefore presents the disadvantage of reduced electrical performance.

Thus, the alignment and position of the platform surface72of the jaw platform70in relation to the internal cavity24of the apparatus10may be sufficient tangent or angled accommodation of the electrical conductor in accordance to industry standards and provide many benefits over conventional insulators.

FIG. 2is a plan view illustration of the first jaw portion140of an electrical insulator apparatus110, in accordance with a second exemplary embodiment of the present disclosure.FIG. 3is a plan view illustration of the second jaw portion150of an electrical insulator apparatus110, in accordance with the second exemplary embodiment of the present disclosure. The electrical insulator apparatus110, which may be referred to herein as ‘apparatus110’ may be substantially similar to the electrical insulator apparatus10of the first exemplary embodiment, and may include any of the structures or functioning described with respect to any embodiment of this disclosure.

As is shown inFIG. 2, the apparatus110differs from the apparatus10ofFIG. 1by including a pocket190within the first jaw portion140to retain a liner member (FIG. 4) therein. The pocket190is recessed within the first jaw portion140and formed perpendicular and leveled with respect to the jaw platform170and may be sized to house the liner member securely to ensure a high gripping strength of the electrical conductor. The hole142may be positioned above the pocket190to receive the fastener in a position above where the liner member will be fitted in the pocket190. The liner member is discussed in detail relative toFIG. 4. The apparatus110may include large radiuses between the components, such as on top and lateral sides of the first jaw portion140. These large radiuses may provide electrical stress control. Furthermore a large radius transition between the first jaw portion140and the plurality of spaced fins126may minimize electrical stress in this region.

As can also be seen, the jaw platform170having the platform surface172may have outer edges that are terminated by two horizontal beams176,178. The two horizontal beams176,178may resist uplift motion of the second jaw portion150when it is secured in place to the first jaw portion140with one or more fasteners (not shown). Additionally, the two horizontal beams176,178may eliminate flexural stress on a fastener engaged with a hole180within the jaw platform170. Below the jaw platform170, two braces182,184may connect between the insulator body120and the jaw platform170to provide long term support and creep resistance capability that the jaw platform170may be susceptible to under a constant weight (vertical load) of the electrical conductor supported by the apparatus110. Beneath the platform surface172, the hole180may be positioned within a lateral jaw face186. The lateral jaw face186may protrude beyond the jaw platform170to increase fastener thread engagement length when accommodating a large conductor.

As is shown inFIG. 3, the second jaw portion150may be designed to engage with the jaw platform170. For example, the second jaw platform150may include two horizontal beams155,156and a rectangular cavity157to receive both horizontal beams176,178of the jaw platform170. Engagement between the rectangular cavity157and the two horizontal beams176,178of the jaw platform170may block the uplift of the second jaw portion150. Above the rectangular cavity157a pocket190may be formed in the second jaw portion150to house another liner member (not shown), to ensure a high gripping strength of the electrical conductor when the first and second jaw portions140,150are compressed around the electrical conductor. The second jaw portion150may include holes152and153(FIG. 3), which are aligned with the threaded holes142,180of the first jaw portion140, respectively, to accommodate the fasteners.

FIGS. 4A-4Dare illustrations of a liner member192for use with the apparatus110ofFIGS. 2-3, in accordance with the second exemplary embodiment of the disclosure. In particular,FIG. 4Aillustrates a plan view of a liner member192, whileFIGS. 4B-4Dillustrate side views of liner members192with surface textures. The liner member192may be at least partially positioned within the pocket190of at least one of the first and second jaw portions140,150, but preferably both of the first and second jaw portions140,150. The liner members192are sized to fit in and be retained by the pocket190of the first and second jaw portions140,150of the apparatus110. The liner member192has a face portion194positioned to contact the conductor. The boundary of the face portion194may have a chamfered edge196to guard against conductor damage should conductor movement occur. The face portion194may be finished with a texture, ribbing or other geometry suitable to grip the conductor without causing harm. For example, the face portion194may be a ribbed pattern (FIG. 4B), an undulating or wave-shaped pattern (FIG. 4C), a friction-enhancing texture, such as sand-paper textured pattern (FIG. 4D), or other suitable pattern, such as raised vertical ribbing, raised diagonal ribbing, and/or raised cross-diagonal ribbing.

By tightening the fasteners, the conductor is secured on the platform surface172(FIG. 2) of the jaw platform170between each liner member192, wherein the liner members192provide a compression force on the conductor. The compression force magnitude is controlled by the torque applied by the fasteners and by the features present at the face portion194of the liner member192. The compression force magnitude may be selected to be directly proportional to the pulling force required to dislodge the conductor from the gripping mechanism, which may be known within the industry as the conductor holding strength, grip strength or gripping strength, and is herein referred to as grip strength. It may be desirable to select the liner members192from a specific material to optimize the grip strength and to reduce, or eliminate, galvanic reaction due to dissimilar metals that may be present in conventional insulator configurations.

Common construction practice for conductor grip strength is to apply the safety rules as described in NESC Section 26 for longitudinal strength. To achieve the NESC strength values, it may be desirable to select a material for the liner member192harder than the conductor in order to resist deflection under load and with textured surface or raised features to improve grip strength. The inorganic material as described in this disclosure, preferably with an undulating face pattern (FIG. 4C) and vertical narrow grooved type texturing, may provide a grip strength exceeding 900 lbf for any size of bare conductor and 650 lbf for any covered conductor. Moreover, as the magnitude of the grip strength for a given liner member192is also dependent on the torque level used to tighten the fasteners. A correlation chart of torque level to grip strength can be compiled to provide users with the flexibility to achieve a specific grip strength value. Such a feature offers the end-user significant flexibility in customizing grip strength for specific situations and conditions.

In addition to providing the aforementioned hardness and the necessary grip strength, the material selected for the liner member192should be chemically inert and stable over time. The liner member material properties are also selected to eliminate galvanic reactions with electrical conductors. An aspect of the present disclosure is to provide compatibility with all types of conductors, such as aluminum, copper and covered, and to provide UV resistance and chemical stability in the presence of moisture and contaminants (e.g. dust, salt, fertilizer or other airborne matter) for the expected lifetime (e.g. 30 years, 40 years, or 50 years, as non-limiting examples). In the outdoor environment, where high humidity and salt-fog conditions may be common, galvanic reaction is expected between metals if their Anodic Index (AI) differs by 0.15 or more. Typical AI values for common materials used in the industry are provided in Table 3:

TABLE 3MaterialAnodic IndexAluminum−0.9Copper−0.35Galvanized Steel−1.2
Given the large AI differences between these materials, none can be a suitable universal liner member192for all types of conductors aforementioned. Thus, it is preferable for the liner member192to be constructed from a material different from a material of the first and second jaw portions140,150, and selection of a non-metallic, electrically non-conductive material is preferred. For example, the liner member192may be a ceramic type material such as Aluminum Oxide (85% to 99.9% purity), Silicon Nitride, Cordierite, Mullite, Steatite, Zirconium Oxide or some other suitable material. The liner member192may be an organic based composite such as UV-stabilized abrasive-filled rubber, glass fiber filled Nylon, or other suitable material.

FIG. 5is a cross-sectional illustration of an electrical insulator apparatus210, in accordance with a third exemplary embodiment of the present disclosure. The electrical insulator apparatus210, which may be referred to herein as ‘apparatus210’ may be substantially similar to the electrical insulator apparatus of any other exemplary embodiment herein, and may include any of the structures or functioning described with respect to any embodiment of this disclosure. The apparatus210includes an insulator body220formed about a central axis222, the insulator body220having an internal cavity224and a plurality of spaced fins226positioned along an exterior of the insulator body220. A first jaw portion240is positioned on the insulator body220. A second jaw portion250(FIGS. 6-7) is connected to the first jaw portion240. At least one fastener260(FIGS. 6-7) is connected between the first and second jaw portions240,250. A jaw platform270has a platform surface272, wherein the platform surface272is formed at least partially between the first and second jaw portions240,250, and wherein a plane274substantially aligned with the platform surface272intersects the internal cavity224.

As is discussed with respect toFIG. 1, the insulator body220ofFIG. 6is used to isolate electrical conductors from the utility fixture, utilizing a plurality of spaced fins226positioned thereon. The insulator body220is formed about the central axis222, such that the central axis222is positioned approximately through the center point of the insulator body220.FIG. 1shows the plurality of spaced fins226positioned coaxial relative to the central axis222of the insulator body220. As shown inFIG. 5, the plurality of spaced fins226may be positioned non-coaxial relative to the central axis222, such that the central axis222is parallel, but not aligned with the fin axis227, i.e., the axis of the plurality of spaced fins226. The distance between the central axis222and the fin axis227may be referred to as an offset distance, which is identified with reference character X inFIG. 5.

In accordance with this disclosure, the offset distance X between the central axis222and the fin axis227may be a value such as to balance or optimize the resistance path to ground, hereinafter referred to as leakage distance, as measured from the jaw platform270across the body of the apparatus210to the inner internal cavity224, in all directions across the plurality of spaced fins226. As an example, the offset distance X may be 0.50 inch or other desired value (e.g. 0.20 inch, 0.40 inch, 0.60 inch or any other suitable value). The offset distance X may vary depending on the size or voltage rating of the electrical conductor that it is designed to retain. For example, the offset distance X may be selected to adjust the leakage distance for a range of conductor sizes (e.g. No. 6 AWG to 2/0 AWG, No. 1/0 AWG to 4287 kcmil, 336 kcmil to 795 kcmil, or any other suitable range) or for a range of system voltages (e.g. 5 kV to 15 kV, 15 kV to 25 kV, 25 kV to 35 kV or any other suitable range). Conventional devices have fins that are coaxial with an insulator device. The non-coaxial positioning of the fins226to the insulator body220of the apparatus210provide improved leakage distance over these conventional devices, in addition to providing a sufficient tangent or angled accommodation of the electrical conductor.

FIG. 6is a side view illustration of the electrical insulator apparatus210ofFIG. 5, in accordance with the third exemplary embodiment of the present disclosure.FIG. 7is a side view illustration of the electrical insulator apparatus210ofFIG. 5, in accordance with the third exemplary embodiment of the present disclosure. BothFIGS. 6-7illustrate the apparatus210in use with a mounting pin212for attachment with a utility fixture and with an electrical conductor.FIG. 6depicts the apparatus210in use with a small diameter electrical conductor214, whereasFIG. 7depicts the apparatus210in use with a large diameter conductor216. Relative toFIGS. 6-7, the electrical conductors214,216may be positioned within the notch formed between the first and second jaw portions240,250, and resting on the platform surface272. The fasteners260may then be tightened to close the first and second jaw portions240,250on the electrical conductor214,216to frictionally retain it in place. One or more liner members may be included on the inner surface of the first and second jaw portions240,250to make physical contact with the electrical conductor214,216, as discussed relative toFIGS. 2-4D. It may be desirable to size the first and second jaw portions240,250and the liner members to provide proper positioning to accommodate a large range of electrical conductor214,216sizes.

The apparatus210ofFIG. 6is shown in the closed position with a small diameter electrical conductor214, such as a No. 6 AWG solid, between the first and second jaw portions240,250, such that the notch formed between the first and second jaw portions240,250and the platform surface272of the jaw platform270is small. It may be desirable to position the liner members such that their lower edge is fixed slightly above the jaw platform270and below the centerline of the electrical conductor214, thus providing direct physical contact with small diameter conductors. The apparatus210ofFIG. 7is shown in the closed position with a large diameter electrical conductor216, such as a 795 kcmil covered conductor, between the first and second jaw portions240,250, such that the notch formed between the first and second jaw portions240,250and the jaw platform270is large. It may be desirable to size the height of the liner members such that the lower edge is fixed slightly above the jaw platform270and the upper edge is fixed above the centerline of the electrical conductor216. The liner members may be capable of providing direct physical contact with a full range of conductor sizes, from small to large diameter.

The positional nature of the jaw platform270with respect to the insulator body220may allow for the apparatus210to be used to string electrical conductors in various configurations, namely along paths that include bends and curves. In other words, the apparatus210may also serve an additional function as an installation tool suitable for the conductor prior to securing in place. For example, the apparatus210may allow for stringing electrical conductors along paths with bends or curves that are greater than 6°, or greater than other angles, such as greater than 20°, 30°, or 45° when used with suitable mounting hardware. When the apparatus210is used to angularly string an electrical conductor, the force that the electrical conductor214,216applies to the apparatus may be transferred into the insulator body220via the first jaw portion240and the jaw platform270, such that the force is applied angularly to the insulator body220. The positioning of the jaw platform270with respect to the insulator body220and the internal cavity224may help counteract the force applied by the electrical conductor214,216better than a conventional insulator device, e.g., a vise-top insulator, since the insulator body220may have a greater resistance to lateral forces created by the electrical conductor due to the bend in the stringing path.

FIG. 8is cross-sectional illustration of an electrical insulator apparatus310, in accordance with a fourth exemplary embodiment of the present disclosure. The electrical insulator apparatus310, which may be referred to herein as ‘apparatus310’ may be substantially similar to the electrical insulator apparatus of any other exemplary embodiment herein, and may include any of the structures or functioning described with respect to any embodiment of this disclosure. The apparatus310includes an insulator body320formed about a central axis322, the insulator body320having an internal cavity324and a plurality of spaced fins326positioned along an exterior of the insulator body320. A first jaw portion340is positioned on the insulator body320. A second jaw portion (not shown) is connected to the first jaw portion340, and at least one fastener (not shown) is connected between the first jaw portion340and the second jaw portion. A jaw platform370has a platform surface372, wherein the platform surface372is formed at least partially between the first jaw portion340and the second jaw portion, and wherein a plane374substantially aligned with the platform surface372intersects the internal cavity324.

As is discussed with respect toFIG. 1, the jaw platform370is aligned along the plane374which intersects the internal cavity324. InFIG. 1, this angle θ was 90°, but the plane374may be oriented at other angles relative to the central axis322while still intersecting the internal cavity324. For example, the intersection of the central axis322and the plane374may be a non-perpendicular intersection. The angle θ may include a plurality of angles between the plane374of the platform surface372of the jaw platform370and the central axis322, preferably between 60° and 150°, but including any angle between 6° and 184°, as measured between the angle formed between the plane374and the central axis322. The angled nature of the platform surface372with respect to the central axis322may enhance the ability of the apparatus310to be used to string electrical conductors in various configurations, namely along paths that include bends and curves, as discussed further relative toFIGS. 9A-9D.

FIGS. 9A-9Dare schematic diagrams of the forces created by an electrical conductor relative to a variety of angles between the platform surface372and the central axis322of the apparatus310ofFIG. 8, in accordance with the fourth exemplary embodiment of the present disclosure. In particular,FIGS. 9A and 9Brepresent the case of an angle θ>90° in tangential and angled constructions, respectively.FIGS. 9C and 9Drepresent the case of an angle θ<90° also in tangential and angled constructions, respectively.

In all four illustrations the vector force components are represented and expressed as a function of the angle θ, where V is the vertical force in the tangent case and C is the cantilever force in the angled case. For θ>90°, in the tangent configuration ofFIG. 9A, the Fpcomponent assists in maintaining the conductor against the liner member392securing it in place, however, in the angled configuration ofFIG. 9B, the FTcontributes to the conductor's uplift in turbulent conditions (e.g. strong wind, galloping, falling tree on conductor, etc.). For θ<90°, in the tangent configuration ofFIG. 9C, the Fcforce causes the conductor to slide back but the fastener is mechanically rated in traction mode to maintain the conductor securely in compression against the liner member392. However, in the angled configuration ofFIG. 9D, the component FRassists the jaws in holding the conductor in place. Depending on the use of the insulator and the construction considered, one can select the optimum angle θ. Thus, the angled jaw platform370of the apparatus310may therefore provide a sufficient tangent or angle accommodation of the electrical conductor.

FIGS. 10A-10Bare plan view illustrations of an electrical insulator apparatus410, in accordance with a fifth embodiment of the present disclosure. The electrical insulator apparatus410, which may be referred to herein as ‘apparatus410’ may be substantially similar to the electrical insulator apparatus of any other exemplary embodiment herein, and may include any of the structures or functioning described with respect to any embodiment of this disclosure. The apparatus410includes an insulator body420formed about a central axis422, the insulator body420having a plurality of spaced fins426positioned along an exterior of the insulator body420. A first jaw portion440is positioned on the insulator body420. A second jaw portion450is connected to the first jaw portion440. At least one fastener460is connected between the first jaw portion440and the second jaw portion450. A jaw platform470has a platform surface472, wherein the platform surface472is formed at least partially between the first jaw portion440and the second jaw portion450, and wherein a plane474substantially aligned with the platform surface472intersects the internal cavity.

The apparatus410includes a rail412formed on the insulator body420which the first jaw portion440, second jaw portion450, and the jaw platform470can be positioned along. InFIGS. 10A-10B, the first jaw portion440, second jaw portion450, and the jaw platform470are shown integral with one another, as one unitary structure, collectively referred to as a gripping mechanism. However, it is noted that these components may also be formed separately and connected together. The rail412is formed radially about the internal cavity424such that the gripping mechanism can be located in the side-saddle position (FIG. 10A) or a top-saddle position (FIG. 10B), or any position therebetween. The rail412may include a plurality of holes414radially spaced thereon, which allow fasteners460to connect the gripping mechanism to the rail412. Accordingly, the use of the rail412with the gripping mechanism to be movable about the insulator body420, thereby allowing the user to select the optimal angular position desired for a particular use.

FIG. 11is a flowchart500illustrating a method of retaining an electrical conductor with an electrical insulator apparatus, in accordance with a sixth exemplary embodiment of the disclosure. It should be noted that any process descriptions or blocks in flow charts should be understood as representing modules, segments, portions of code, or steps that include one or more instructions for implementing specific logical functions in the process, and alternate implementations are included within the scope of the present disclosure in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present disclosure.

As is shown by block502, the electrical insulator apparatus is secured to a utility fixture, wherein a pin affixed to the utility fixture engages with an internal cavity of an insulator body of the electrical insulator apparatus. A portion of the electrical conductor is retained within a receiving notch formed on the insulator body between a first jaw portion, a second jaw portion, and a jaw platform, wherein the portion of the electrical conductor contacts a platform surface of the notch, wherein a plane of a platform surface of the jaw platform is aligned to intersect the internal cavity, wherein the portion of the electrical conductor applies a longitudinal force against the pin within the cavity (block504). The method may include any additional step, process, or function, including any disclosed relative to any figure of this disclosure. For example, the plane of the platform surface may be angled substantially between 60° and 150° relative to a central axis of the insulator body and the longitudinal force applied against the pin may be dependent on an angle size of the angle. The longitudinal force may be 500 lbf or greater.