Abstract:
A wildlife deterrent for a utility support structure member between two conductors includes a bracket for attachment to the supporting member, a center support piece with a variable height arm connector, and two adjustable arms pivotally attached to the arm connector. No tools are required for the adjustments or attachments. Since the effective lengths of the support and arms are adjustable, either by elongation or using different length parts, the same angle of the arms can be achieved no matter what the separation between the conductors, and the gap between the arms and the conductor can be optimal for both deterrence and flashover prevention. The different pieces forming the deterrent can be selected by the lineman to quickly build an optimal deterrent in the field.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a wildlife deterrent for use on an electric transmission and distribution system structure, such as a crossarm, pole, or other supporting structure, to prevent electrocution of birds and other wildlife that complete an electrical path phase to phase or phase to ground. 
       BACKGROUND 
       [0002]    Electrical transmission and distribution circuits include conductors supported by grounded support structures such as wooden poles, steel poles, concrete poles, and lattice towers. The support structures are essentially grounded since they are embedded in the earth. Each conductor (or wire) is separated from the grounded structure by an insulator, such as a ceramic insulator. The insulators also provide separation between the conductors (or phases). The phase separation is determined by the circuit voltage, the proximity to ground, and the length of the span. 
         [0003]    Insulators are manufactured in various sizes and shapes according to industry standards. The insulator chosen for use on a support structure varies in size and is dependent on the circuit voltage as well as other electrical and physical characteristics. 
         [0004]    The construction and design of support structures vary for single phase and three phase electrical circuits. The insulators and phases attached to a crossarm or supporting member may all be at the same level horizontally and separated a certain distance according to industry standards. Or, they may be configured vertically and attached to the support structure by means of a bracket or supporting member. 
         [0005]    The distance between the insulators, energized phases, and ground potential varies according to the circuit voltage and other characteristics. If a bird, squirrel, or other animal perched or sitting on a support structure, supporting member, conductor, or insulator completes a circuit phase to phase, or phase to ground, a flashover will occur, resulting in an outage, disrupting power to customers, and the death of the animal. 
         [0006]    Electricity is always seeking a path to ground. Therefore, industry guidelines recommend that energized conductors have adequate separation phase to phase and phase to ground. This separation is referred to as clearance. Electricity flows over the surface of a conductor or insulator. With regards to insulators, the separation or surface area between the conductor and ground is referred to as leakage distance. Typically, insulators are manufactured with skirts to lengthen the surface distance phase to ground and minimize the overall height of the insulator. If an animal approaches the energized conductor or insulator and provides a conductive path to ground, or if an animal effectively reduces the necessary separation or clearance of two energized conductors, a short will occur in the circuit, resulting in a momentary or permanent outage. Depending on the circuit voltage, this animal does not necessarily have to come in direct contact with the energized conductor or insulator for the electricity to discharge across to the conductive path. Mylar balloons have also been known to create the short circuit. Additionally, the shorting could also be caused by an improperly installed or damaged wildlife deterrent device installed by a lineman with insufficient clearance from the energized conductors and insulators. It is essential that adequate separation or clearance be maintained phase to ground and phase to phase. 
         [0007]    The present invention relates to an improved wildlife deterrent for use on a high voltage utility support structure, such those generally used to support electrical distribution conductors between substations and homes or businesses. The conductors typically carry AC voltages under 75 kV and as little as 120V. Such supporting structures may have multiple supporting members, where the highest supporting member supports conductors carrying the highest voltage. Medium to high voltage conductors are frequently not shielded by insulation. 
         [0008]    Some wildlife deterrents are known. One type of deterrent is a preformed plastic triangle that is bolted to the support member between two conductors, where the closest distance between a triangle arm and a conductor is insufficient to cause a flashover through the plastic but close enough to prevent an animal going between the conductor and the triangle. However, although rigidly-shaped deterrents may be suitable for some insulator spacings, the same deterrent may not be suitable for a range of insulator spacings. Therefore, different sizes of such deterrents must be on hand for the lineman, or a compromise must be made by using the single deterrent for different situations. 
         [0009]    An adjustable-angle deterrent is manufactured by Hendrix Conductor &amp; Cable, Inc. that consists of two arms attached at a pivot point. The arms are spread to provide the desired distance between each arm and its closest conductor, while not leaving room for an animal to perch between the arm and the conductor, and the free ends of the arms are nailed or lagged to the supporting member to form a triangle. However, with such a deterrent, the angle becomes less and less as the arms are spread wider and wider to accommodate different spacings of conductors. This design cannot be used on metal or concrete type supporting structures due to the method of nailing or lagging. Therefore, there must be a compromise between: 1) the closest space between the deterrent and the conductor to deter wildlife yet avoid flashover between the conductor and the deterrent; and 2) the angle of the arms, where a steep angle of the arms is needed to deter animals perching on the arms. 
         [0010]    Another type of wildlife deterrent, manufactured by Midsun Group, Inc., has a fixed-length vertical rod and two sets of three pivoting arms extending from opposite sides of the vertical rod. The six arms prevent a bird from roosting on the support member, provided the insulators and conductors are spaced adequately from the arms of the deterrent. If the insulators and conductors are spaced beyond the maximum width of the deterrent and there is too much clearance between the deterrent and the insulator, the deterrent becomes ineffective. Further, as the arms are spread out and become more horizontal to widen the overall design of the deterrent, the arms do not maintain the angle needed to discourage a bird from landing on them. The deterrent effectively becomes an inviting perch instead of a deterrent to perch. 
         [0011]    Conversely, if the insulators are spaced close together, the deterrent may jeopardize the phase to phase spacing. 
         [0012]    What is needed is an adjustable wildlife deterrent for utility support structures that can be easily and quickly configured by the lineman for optimal deterrence by maintaining critical angles to discourage birds and wildlife from perching and sitting next to energized conductors and insulators and provide the necessary adjustability for clearance issues to prevent flashover from occurring phase to ground, phase to phase, with varying conductor and insulator spacings. 
       SUMMARY OF THE INVENTION 
       [0013]    In one embodiment, a wildlife deterrent for a utility support structure is attached to a conductor/insulator supporting member between two conductors. The deterrent includes a bracket for attachment to a supporting member, a separate center support piece having an adjustable height arm connector, and two variable-length arms pivotally attached to the arm connector on the center support piece, where the other ends of the arms are connectable to the supporting member. The variable-length arms may be adjustable-length arms or an assortment of arms of different lengths. The deterrent forms a triangle shape when connected together, and since the height of the arm connector on the center support and the lengths of the arms are variable, the optimal angle of the arms can be achieved and maintained no matter what the separation between the conductors, and the gap between the arms and the conductors can be optimal for both deterrence and flashover prevention. 
         [0014]    In another application, the deterrent is next to a conductor on one side but there is no conductor proximate to the other side of the deterrent. 
         [0015]    In another embodiment, the pivotally attached arms are short and have ends that do not attach directly to the supporting member. 
         [0016]    In one embodiment, the arms may be attached anywhere along the length of the center support, allowing any number of arms to be connected. 
         [0017]    In one embodiment, the center support has an adjustable height, rather than or in addition to the arm connector being connectable anywhere along the center support. 
         [0018]    In one embodiment, the deterrent can be mounted on the side of a vertical support structure that supports conductors running along the sides of the support structure, where the variable arms only extend from one side of the center support piece. 
         [0019]    In one embodiment, the same arms may be used for connection to the center support piece to create a medium or large deterrent or connected directly to each other at their pivot point for creating a small deterrent for closely spaced conductors. 
         [0020]    All attachments and adjustments are made by hand-operated clips, or other types of interlocking devices, so no tools are needed. The entire structure is formed of a plastic (e.g., PVC) or other dielectric. 
         [0021]    The invention allows many different sizes and shapes of deterrents to be created using the same parts. Forming a deterrent to have customized characteristics, depending on the conductor spacing and type of support structure, enables a lineman to optimize the deterrent in the field without requiring the stocking of many different sizes and shapes of deterrents. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1A  illustrates one embodiment of a wildlife deterrent, in accordance with an embodiment of the invention, mounted on a supporting member of a utility support structure. 
           [0023]      FIG. 1B  illustrates the deterrent of  FIG. 1A  being optimized for conductors having a close spacing of D. 
           [0024]      FIG. 1C  illustrates the deterrent of  FIG. 1A  being optimized for conductors having a wider spacing of 1.5 D by adjusting the lengths of the center support and arms and adjusting the arm angles. 
           [0025]      FIG. 2  is a side view of the adjustable-length center support of  FIG. 1A . 
           [0026]      FIG. 3  is a perspective view of the adjustable-length center support of  FIG. 2 . 
           [0027]      FIG. 4  is a front view of an adjustable-length pivoting arm connectable anywhere along the length of the center support of  FIG. 3 . (The arms are shown in their minimum length position for storage.) 
           [0028]      FIG. 5  is a side view of the adjustable-length pivoting arm of  FIG. 4 . 
           [0029]      FIG. 6  is a perspective view of the adjustable-length pivoting arm of  FIG. 4 . 
           [0030]      FIG. 7  is a front view of a connector that is connectable along the length of a center support and is used to pivotally connect the arm of  FIG. 4  to the center support of  FIG. 3 . 
           [0031]      FIG. 8  is a perspective view of the connector of  FIG. 7 . 
           [0032]      FIG. 9  illustrates the center support of  FIG. 3  supporting arms that do not extend down to the supporting member, where the downward angle of the arms is limited by a mechanical stop. 
           [0033]      FIG. 10  illustrates a deterrent mounted on the side of a vertical support structure. 
           [0034]      FIG. 11  illustrates a variation of the deterrent of  FIG. 9 . 
           [0035]      FIG. 12  is a front view of arms connected at a pivot point that may be the same arms connectable to the connector of  FIG. 7 , illustrating the various configurations of deterrents that may be created with the same set of parts. 
           [0036]      FIG. 13  is a perspective view of the arms of  FIG. 12 . 
           [0037]      FIG. 14  illustrates another embodiment of a deterrent similar to  FIG. 1A  but using a different type of interlocking device for all the pieces. 
           [0038]      FIG. 15  is a front view of the bracket used in  FIG. 14 . 
           [0039]      FIG. 16  is a side view of the bracket used in  FIG. 14 . 
           [0040]      FIG. 17  is a front view of the center support used in  FIG. 14 . 
           [0041]      FIG. 18  is a side view of the center support used in  FIG. 14 . 
           [0042]      FIG. 19  is a perspective view of the connector used in  FIG. 14  for attachment of the arms to the center support. 
           [0043]      FIG. 20  is a front view of an arm that may be connected to the connector of  FIG. 19  or directly to the center support of  FIG. 17 , where the arm may either be adjustable in length or come in different lengths. 
           [0044]      FIG. 21  is a front view of two arms, identical to the arm of  FIG. 20 , being pivotally connected together for a small or otherwise simple deterrent. 
           [0045]      FIG. 22  illustrates the center support of  FIG. 17  supporting arms that do not extend down to the supporting member, where the downward angle of the arms is fixed by the connection of two interlocking devices to the connector. 
           [0046]      FIG. 23  is a perspective view of the connector used in  FIG. 22 . 
           [0047]      FIG. 24  is a front view of one of the arms in the deterrent of  FIG. 22 . 
           [0048]      FIG. 25  is a side view of one of the arms in the deterrent of  FIG. 22 . 
       
    
    
       [0049]    Elements labeled with the same numerals may be identical or similar. 
       DETAILED DESCRIPTION 
       [0050]      FIG. 1A  illustrates an embodiment of the wildlife deterrent  10  in accordance with one embodiment of the invention. A bracket  12  for the deterrent  10  is nailed or lagged (using a lag screw) to a wooden supporting member  14  of a utility support structure  15 . An adjustable-length center support  16  is connected to the bracket  12  by hand-releasable clips (seen in greater detail in  FIG. 3 ). Two arms  18  are connected near the top of the center support  16 , via a connector piece  19 , by hand-releasable clips (seen in greater detail in  FIGS. 6-8 ). The entire deterrent  10  may be molded plastic, such as one-eighth inch thick PVC or polyethylene. The plastic is of a type that has well-defined dielectric characteristics and long life outdoors. 
         [0051]    The center support  16  has an adjustable length to allow the deterrent  10  to be adapted to different separations between conductors  20 . Each conductor  20  is supported by a ceramic insulator  22  bolted through the supporting member  14 . The conductor voltage will typically be less than 75 kV and most likely less than 50 kV. 
         [0052]    In one embodiment, the arms  18  have an adjustable length. In another embodiment, the lineman selects from a plurality of arms  18  in stock having different lengths, depending on the optimal shape of the deterrent  10 . 
         [0053]    The optimal shape of the deterrent  10  is when the arms  18  are close enough to the conductors  20  to prevent a bird, squirrel, or other targeted animal from perching or walking between the arm  18  and the conductor  20 . There is no problem with flashover if the animal goes between the two arms  18 , since the animal could not touch a conductor  20 . Another aspect of an optimal shape of the deterrent  10  is having the arms  18  at a steep angle with respect to horizontal so that a bird would not perch on the arms  18 . A good angle is between 50°-77° relative to the supporting member  14 . To provide both optimal attributes of the deterrent  10 , the center support  16  is adjustable in height, and the arms  18  are either adjustable in length or selected from a stock of arms  18  of different lengths. All adjustments should be made without the use of tools. 
         [0054]      FIG. 1B  illustrates the deterrent  10  optimally configured for closely spaced insulators  22  with a spacing of D, and  FIG. 1C  illustrates the deterrent  10  optimally configured for widely spaced insulators  22  with a spacing of 1.5 D. The same deterrent  10  may be used in  FIGS. 1B and 1C , with its center support  16  and arms  18  lengthened using the clips and holes shown in  FIGS. 2-8 . In one embodiment, the lengths of the center support  16  and arms  18  are adjustable up to being approximately double the minimum lengths. For a supporting member supporting three conductors (two spaces between conductors), two deterrents  10  would be used on the supporting member, and the deterrents  10  would have different configurations if the spacings between the conductors were different. 
         [0055]      FIG. 2  is a side view of the center support  16  and attached bracket  12 , and  FIG. 3  is a perspective view of the support  16  and bracket  12 . 
         [0056]    The bracket  12  has sides that fit over a standard supporting member and has small holes for being nailed or screwed to the supporting member. The bracket  12  has a receiving area  26  for the center support  16  with resilient plastic clips  28  that snap into the two bottom holes in the center support  16  to firmly secure the support  16  to the bracket  12  and supporting member. All the clips used throughout the deterrent  10  may be identical. 
         [0057]    The support  16  consists of a lower portion  30  and a narrower upper portion  32  that slides with respect to the lower portion  30  within a channel. The lower portion  30  includes two clips  34  near its top. Any set of holes  36  along the length of the upper portion  32  can be pushed over the clips  34  to secure the upper portion  32  in place for adjusting the length of the center support  16 . 
         [0058]      FIG. 7  is a front view of a connector piece  19  for the center support  16  that snaps into the top two holes of the upper portion  32  using resilient clips  42 .  FIG. 8  is a perspective view of the connector piece  40 . The clips  42  may be released by pushing up or down on them. 
         [0059]    Adjustable arms  18  are shown in the different views of  FIGS. 4-6 . The arms  18  shown are short for illustration but may be adjustable from 1.5-3 feet. The arms  18  are also shown in their stored configuration, having their minimum length for storage. Other adjustable lengths are envisioned along with fixed length arms of any length for use with the adjustable center support  16 . A top clip  44  of an upper arm  46  clips into a hole  48  in the connector piece  19  ( FIG. 7 ) to allow the upper arm  46  to pivot. The upper arm  46  includes a pair of oppositely-engaged clips  50  that engage any pair of holes  52  in a lower arm  54  to adjust the overall length of the arm  18 . The maximum length of the arms  18  should be greater than the maximum length of the center support  16 . The adjustable arms  18  use the same basic adjustment mechanism as the upper and lower portions of the center support  16  but do not need to be as robust. 
         [0060]    The end of the lower arm  54  includes holes  56  for nailing or screwing to the supporting member. 
         [0061]    Since the deterrent  10  is formed of various pieces that easily snap together, any combination of the pieces is possible.  FIG. 9  illustrates a deterrent  60  whose arms are only formed of the upper arm  46  portion. The top clip  44  of the upper arm  46  is snapped into the hole  48  ( FIG. 8 ) of the connector piece  19 . A plastic stop (a tab)  62  extends from the upper arm  46  and fits within a groove  64  formed in the connector piece  19  to limit the downward angle of the arms  46  to provide support. The stop  62  is also shown in the  FIG. 5  side view of the upper arm  46 , where the stop  62  is shown extending through a hole in the lower arm  54  when the arms are in their minimum length configuration during storage. 
         [0062]    As shown in  FIG. 9 , a second connector piece  19  is clipped to the center support  16  at a midway position to support a second set of arms  46 . 
         [0063]    The center support  16  in  FIG. 9  can be any length, and the arms could be the adjustable types so that the arms could be adjusted to span any practical distance between conductors (to prevent an animal contacting a conductor while perching on the supporting member) while being at an optimal angle for deterring birds landing on the arms. Any number of arms can be attached to the support  16  by adding more connector pieces  19 . 
         [0064]      FIG. 10  further illustrates the flexibility of forming a deterrent from various pieces, where the deterrent is mounted to the side of a support structure  68 . In  FIG. 10 , the same deterrent of  FIG. 9  is used but with the upper arms  46  extending from only one side of the support  16  to prevent a bird from perching on the insulator  69 . A bird would not perch on the steeply angled upper arms  46 . 
         [0065]      FIG. 11  illustrates a deterrent  70  formed of PVC piping. A lower portion  72  of the center support  73  receives a smaller-diameter upper portion  74  that slides within the lower portion  72 . When the desired length is achieved, a key  76  or other locking device is inserted through the aligned holes to fix the length. The arms  78  are supported by sleeves  80  that slide along the length of the upper portion  74  or the lower portion  72 . When the desired position is achieved, a key or locking device is inserted through the aligned holes to fix the position. 
         [0066]      FIG. 12  (front view) and  FIG. 13  (perspective view) illustrate a different arm design. The arms  86  are identical and each includes a plastic clip  88  at one end. The arms  86  may be directly snapped together and affixed to a supporting member using nails without a center support  16  ( FIG. 3 ), or the arms  86  may be connected to the connector piece  19  ( FIG. 8 ) that is snapped onto the center support  16 . The lineman snaps the deterrent together in the field to adapt to a certain situation. The arms  86  may come in a variety of lengths rather than be adjustable. Alternatively, the arms that are snapped together in the configuration of  FIGS. 12 and 13  may be the adjustable type shown in  FIGS. 4-6 . 
         [0067]    The required spacings between the plastic arms and the conductors may be found in existing publications published by IEEE, or the electric company, or other sources. The National Electrical Safety Code identifies required distances between out-of-phase conductors and between conductors and ground for various voltages. 
         [0068]      FIGS. 14-25  illustrate insulating (e.g., molded plastic) deterrents and interlocking pieces used to create a deterrent, where the interlocking device comprises an inverted keyhole shaped opening (a round opening with a narrowed slot) in one piece and a flat round head with a short neck on another piece, where the head is inserted through the round opening and slid so that the neck moves into the slot. 
         [0069]      FIG. 14  illustrates a deterrent  100  similar to  FIG. 1A  but using a different type of interlocking device for all the pieces.  FIG. 15  is a front view of the bracket  102  used in  FIG. 14 , and  FIG. 16  is a side view of the bracket  102  used in  FIG. 14 . The bracket  102  may be nailed or screwed to support member  14  in  FIG. 14 . The bracket has an inverted keyhole opening  104  and a slot  106  identical to the bottom of the opening  104 . 
         [0070]      FIG. 17  is a front view of the center support  108  used in  FIG. 14 , and  FIG. 18  is a side view of the center support  108  used in  FIG. 14 . The center support  108  has inverted keyhole openings  110  identical to the inverted keyhole opening  104  in the bracket  102 . At the bottom of the center support  108  are two raised heads  112 . For attachment to the bracket  102 , the bottom head  112  is inserted through the opening  104 , and the center support  110  is pushed downward to lock the heads  112  within the slots (slot  106  and bottom of opening  104 ). All parts are molded as unitary pieces. 
         [0071]      FIG. 19  is a perspective view of the connector  114  used in  FIG. 14  for attachment of the arms  116  to the center support  108 . The connector  114  has heads  118  that lock into any two openings  110  in the center support  110  so may be at any height to create an optimal angle of the arms  110 . 
         [0072]      FIG. 20  is a front view of an arm that may be connected to the connector  114  of  FIG. 19  or directly to the center support  110  of  FIG. 114 . To connect the arm  116  to the right side of the connector  114 , the inverted keyhole opening  120  of the arm  116  is locked onto the raised head  122  of the connector so it can pivot. The other end of the arm  116  is then set at the optimal angle and nailed or screwed to the supporting member  14  ( FIG. 14 ) through one or more of the small holes  124  in the arm  116 . To connect the arm  116  to the left side of the connector  114 , the raised head  126  is inserted into the opening  128  of the connector  114  and locked in place so it can pivot. The other end of the arm  116  is then set at the optimal angle and nailed or screwed to the supporting member  14  ( FIG. 14 ) through one or more of the small holes  130  in the arm  116 . 
         [0073]      FIG. 21  is a front view of two identical arms  116  being pivotally connected together by inserting the head  126  into the opening  120  and locking the arms together for a small or otherwise simple deterrent  132 . The free ends of the arms  116  are nailed or screwed to the supporting member  14  ( FIG. 14 ) after creating an optimal angle of the arms  116 . It is envisioned that the lineman will store in his vehicle arms  116  of various lengths, such as 10-30 inches, so that any span of the deterrent  132  can be created with any angle of the arms  116 . 
         [0074]    The deterrent  136  of  FIG. 22  is similar to deterrent  60  of  FIG. 9 , except for the type of interlocking device. The bracket  102  and center support  108  may be identical to that shown in  FIG. 14 . The connector  138  for the arms  140  can be positioned anywhere along the center support using the interlocking heads  142  and openings  144 .  FIG. 23  is a perspective view of the connector  138  used in  FIG. 22 . 
         [0075]      FIG. 24  is a front view of one of the arms  140  in the deterrent of  FIG. 22 , and  FIG. 25  is a side view of one of the arms  140 . The heads  146  snap into the respective openings  148  in the connector  138  so that the arms  140  are fixed in place and do not pivot. The lineman would stock arms  140  of different lengths, such as 8-20 inches, and stock center supports  108  of different lengths to achieve the necessary spans. If desired, the free ends of the arms  140  can be nailed or screwed to the supporting member  14  via holes  150 . 
         [0076]    Other types of interconnecting devices can also be used. 
         [0077]    Having described the invention in detail, those skilled in the art will appreciate that, given the present disclosure, modifications may be made to the invention without departing from the spirit of the inventive concept described herein. Therefore, it is not intended that the scope of the invention be limited to the specific embodiments illustrated and described.