Abstract:
A diverter for diverting birds away from overhead lines includes a plastic plate substrate having an upper portion and a lower portion. The upper portion is narrower than the lower portion such that a center of gravity is lower. The substrate includes a central portion and triangular-shaped left and right edge portions. The triangular portions are narrow to wide from top to bottom. The central portion includes an opening at an upper portion thereof for attachment to a ring. The central portion includes front and rear flat surfaces each having an upper area and a lower area. One of the front flat surface upper and lower areas includes a first fluorescent retroreflective sheet. One of the rear flat surface upper and lower areas includes a second fluorescent retroreflective sheet. The first and second fluorescent retroreflective sheets having respective contrasting colors. Another one of the front flat surface upper and lower areas and another one of the rear flat surface upper and lower areas includes a luminescent material.

Description:
RELATED APPLICATION 
     This is a nonprovisional application claiming the priority benefit of provisional application Ser. No. 61/213,359, filed Jun. 2, 2009, hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is generally directed to warning devices and particularly to warning devices to scare or divert birds away from structures subject to bird collision such as overhead power lines, guy wires, etc. 
     SUMMARY OF THE INVENTION 
     The present invention provides a diverter for diverting birds away from overhead lines, comprising a plastic plate substrate having an upper portion and a lower portion. The upper portion is narrower than the lower portion such that its center of gravity is lower. The substrate includes a central portion and triangular-shaped left and right edge portions. The triangular portions are narrow to wide from top to bottom. The central portion includes an opening at an upper portion thereof for attachment to a ring. The central portion includes front and rear flat surfaces each having an upper area and a lower area. One of the front flat surface upper and lower areas includes a first fluorescent retroreflective sheet. One of the rear flat surface upper and lower areas includes a second fluorescent retroreflective sheet. The first and second fluorescent retroreflective sheets having respective contrasting colors. Another one of the front flat surface upper and lower areas and another one of the rear flat surface upper and lower areas includes a luminescent material. 
     The substrate is preferably trapezoidal-shaped for a lowered center of gravity. It has a central portion which is substantially rectangular. The luminescent material may be embedded within the substrate. The luminescent material is preferably a sheeting material adhesively attached to lower portions of the front and rear surfaces. The fluorescent orange retroreflective sheet and the fluorescent yellow-green retroreflective sheet are preferably adhesively attached to the substrate. The triangular edge portions are turned at an angle relative to the plane of the substrate in the same direction. The angle is preferably about 45°. The fluorescent orange retroreflective sheet occupies substantially one-half of the front surface. The fluorescent yellow-green retroreflective sheet occupies substantially one-half of the rear surface. The luminescent material is preferably a sheet that occupies substantially one-half of the front or rear surfaces. The several sheets are substantially rectangular. The opening has a wall having with a crown to minimize friction with the attaching ring, thereby affording greater looseness and movement to the substrate in the wind. The substrate is attached to a ring through the opening and a swivel is attached to the ring to allow vertical rotation of the substrate. The first fluorescent retroreflective sheet is orange and the second fluorescent retroreflective sheet is yellow-green. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a diverter made in accordance with the present invention. 
         FIG. 2  is a perspective view of the diverter shown in  FIG. 1 . 
         FIG. 3  is a front elevational view of the diverter shown in  FIG. 2 . 
         FIG. 4  is a cross-sectional view taken along line  4 - 4  in  FIG. 3 . 
         FIG. 5  is a bottom end view of  FIG. 3 . 
         FIG. 6  is a perspective view of another embodiment of a diverter made in accordance with the present invention. 
         FIG. 7  is an enlarged detail A showing a crown in the opening. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment of a diverter  2  made in accordance with the present invention is disclosed in  FIG. 1 . The diverter  2  is attached to an overhead power line  4  through a conventional clamp  6  and a standard swivel assembly  8 . The diverter  2  uses light through reflectance and refraction, and motion through rotation, oscillation and vibration to divert birds away from the power line and other structures on which birds typically perch or against which birds may collide. 
     The diverted  2  is made of a rigid plastic plate substrate  3 , such as acrylic translucent plastic, preferably ultraviolet light (u.v.) resistant to withstand typical outdoor environment. The translucent plastic absorbs stray light in low light conditions and will not break down under natural sunlight exposure. This type of plastic advantageously magnifies and enhances the fluorescent material that is applied to the surface of the substrate, as will be discussed below. 
     The substrate  3  is preferably substantially trapezoidal-shaped, as shown in  FIGS. 2 and 3 , for a lowered center of gravity. Opposing triangular-shaped left and right edge portions  10  and  12  act as wings to increase rotation and improve aerodynamics of the diverter  2  in the wind. The left and right edge portions  10  and  12  are narrower at the top and wider at the bottom. The edge portions  12  and  10  are turned in the same direction relative to the plane of the substrate central portion  14 , as shown in  FIG. 5 , at an angle  20 , preferably at about 45°. Wind tunnel testing has shown that the diverter  2  begins rotation and vibration during periods of 3-5 mph wind in the outside environment. The trapezoidal shape makes the substrate  3  narrower at the top and wider at the bottom to advantageously lower the center of gravity of the diverter  2 . A lower center of gravity allows the diverter  2  to maintain its vertical orientation for greater visibility to the birds. 
     The substrate  3  central portion  14  is substantially rectangular with front and rear flat surfaces  16  and  18 , as shown in  FIGS. 4 and 5 . Fluorescent sheeting materials  22  and  24 , preferably rectangular, are adhesively attached to the upper front and rear upper surfaces  16  and  18 , as shown in  FIGS. 3 and 4 . The sheeting materials  22  and  24  advantageously refract and reflect ambient light to make the diverter  2  visible to the birds. Since the substrate  3  is translucent, light can enter within the plastic material and emerge out through the sheeting materials  22  and  24  to help brighten the fluorescent colors. The sheeting materials  22  and  24  each occupies substantially one-half of the respective front and rear surfaces  16  and  18 . 
     Birds utilize refracted light in their feathers for communication and courtship display (e.g. iridescent colors in peacock feathers are refracted light not pigments in the feather structure). The diverter  2  refracts natural sunlight similar to the sunlight refracting from the bird&#39;s own feathers. This makes the diverter  2  a man-made feather in reality. Birds can see the diverter  2  and will not sit within about 25 foot radius when the u.v. index is greater than 2.0 (as calculated by the EPA for each city in the USA) and the diverter  2  is rotating or vibrating in the wind. 
     The sheeting material  22  is preferably fluorescent orange that refracts natural and artificial light. Light is refracted light in the 590 nm range within the spectrum of visible white light. An example of this material is available from 3M, called Fluorescent Orange Prismatic Work Zone Sheeting, described in Product Bulletin 3924S (October 2007), herein incorporated by reference. The sheeting material  22  consists of prismatic lenses formed in a transparent resin, sealed and backed with a pressure-sensitive adhesive and poly liner. The sheeting material  22  is retroreflective. The sheeting material  22  provides the prism or rainbow effect that refracts the spectrum of white light to make the diverter  2  visible to the approaching bird. 
     The sheeting material  24  is preferably fluorescent yellow-green that refracts natural and artificial light. Light is refracted light in the 570 nm range within the spectrum of visible white light. This material is mounted on the opposite side of the orange material  22  on the substrate  3 . An example of this material is available from 3M called Diamond Grade™ Fluorescent VIP Reflective Sheeting, described in Product Bulletin 3980 (September 2005), herein incorporated by reference. The material is a visible-activated fluorescent wide angle prismatic lens reflective sheeting. The sheeting material  24  provides the prism or rainbow effect that refracts the spectrum of white light to make the diverter  2  visible to the approaching bird. 
     By mounting these different colors on both sides of the diverter  2 , the contrast of the colors during rotation, oscillation, and/or vibrations is enhanced to approaching birds and bats and thereby causing the wildlife to avoid collisions with wires and other man-made objects that have been marked with the diverter  2 . The sheeting materials  22  and  24  are advantageously mounted on the upper portions of the substrate  3  to place them closer to the wire  4  on to which the diverter  2  is attached. This location is effective in preventing the birds from perching on or near the clamp  6  and covering the sheeting materials with bird droppings. 
     Fluorescent orange and yellow-green reflective materials advantageously provide daylight (diurnal) peak color to the passing or roosting birds. Research on avian vision has shown that birds in general see 5 times the concentration of fluorescent color than humans. The translucent acrylic plastic substrate  3  enhances the visibility to marked wires to birds and bats during the low-light conditions found during sunrise and sunset periods. 
     The diverter  2  incorporates tetra chromatic avian vision properties found in bird feathers. Humans utilize only tri-chromatic vision—red, green, and blue colors. Birds utilize tetra (4) chromatic vision—red, green, blue, and ultra violet. Ultra-violet color is invisible to the human naked eye, but visible to birds which have UV rods and cones within their retinas. Humans have no such UV rods and cones. The fluorescent orange and yellow-green sheeting materials  22  and  24  reflect UV-A (long wave) and UV-B (shortwave) sunlight, causing the perching bird to remain at a hazing distance of about 25 feet from the diverter  2 . 
     Luminescent sheeting materials  26  and  28 , preferably rectangular, are adhesively attached to the lower front and rear upper surfaces  16  and  18 , as shown in  FIGS. 3 and 4 . The sheeting materials  26  and  28  each occupies substantially one-half of the respective front and rear surfaces  16  and  18 . The sheeting materials  26  and  28  advantageously absorb UVA and UVB at 360 nm and below during the daytime and provides light (phosphorescence; glow in the dark) during the nighttime in the 540 nm range. An example of this material is available from 3M, called Luminous Film 6900, describe in Product Bulletin 6900 (June 2002), herein incorporated by reference. The sheeting materials have pressure-sensitive adhesive. 
     The phosphors in the sheeting materials  26  and  28  absorb UVA and UVB at 360 nm and reflect sunlight by the shiny crystalline structure of zinc sulfide used. Birds can see this as a violet color. This color is not visible to the human eye which cannot see below 400 nm of the visible spectrum of sunlight. The luminescent sheeting materials  26  and  28  are visible to both diurnal and nocturnal bird migration over the marked wires. The phosphorescence of the sheeting materials  26  and  28  advantageously extends visibility to 10-12 hours after sundown to the diverter-marked wires. 
     Glow crystals  30 , such as zinc sulfide and doped strontium aluminate, may be imbedded within the manufactured acrylic plastic substrate  3 , as shown in  FIG. 6 , instead of being applied as a sheeting material on the surface of the substrate  3 . After sundown, the translucent acrylic plastic substrate  3  with the embedded glow crystals glows in the dark for 10-12 hours to alert passing birds of an obstruction ahead on the marked wire. The glow in the dark natural crystals absorb and emit purple ultraviolet light visible to the birds as violet but appears as white to humans. 
     The diverter  2  advantageously makes the wire look larger in diameter to the birds by means of the reflective peak colors during the day and emitting afterglow light in low light, fog, and night time. 
     The diverter  2  has an opening  32  through its upper end portion through a longitudinal centerline  34  which passes through the center of gravity. The opening  32  is preferably reinforced with raised ridge  35  for durability. The opening  32  is loosely attached to a ring  36 , which is loosely attached to a swivel  38  that allows 360 degree rotation in the vertical axis. The swivel  38  is further loosely attached to another ring  40 , which is loosely attached to the clamp  6 . The opening  32  has a crown  37  in the opening wall to minimize friction between the ring  36  and the opening wall, to promote looseness and freedom of movement of the substrate  3  in the wind. 
     The swivel  38  allows for rotation about the centerline  34  to give increased contrast to migrating birds and bats by the alternating patterns of yellow-green and orange fluorescent colors given by the sheeting materials  22  and  24  on the opposite sides of the substrate  3 . The triangular edge portions  10  and  12  are acted upon by the wind to rotate the diverter  2  like a bullet about the centerline  34 . 
     The loose interconnection of the diverter  2  to the clamp  6  allows for oscillation back and forth movement (wiggling action) in natural wind conditions, increasing visibility to migrating bats and birds approaching diverter-marked wires and structures. The diverter  2  wiggles back and forth about the rings  36  and  40 , flashing at approaching birds during windy days. 
     The diverter  2  when mounted by removable conventional spring-loaded clamp  6  on wires, such as power lines, tower guy wires, and other tensioned wires, vibrates to alert migrating birds and bats to wire collision hazards. The vibration comes from the natural vibration of power lines typically tensioned at 32 lbs per square inch. Research has shown that birds can see very small movement of objects at much greater extent than human beings. 
     The diverter  2  has been shown to cause a change in flight behavior when applied to power line and other wires suspended in the air. Approaching birds begin to change flight behavior up to ¼ of a mile from the diverter-marked wires, thereby avoiding collisions and injury or death to the birds. 
     The diverter can be safely applied to energized power line conductor wire up to 115 kV with no coronal emission problems or radio and TV interference. Materials used in the diverter are rated to withstand the natural elements for long periods of time without degradation, typically 5-10 years. The diverter provides visibility in both daylight (diurnal) and nighttime (nocturnal) light conditions. The diverter can be applied by electrical lineman crews on energized wires without having to turn off the power grid during marking of the wires. The diverter is several times more visible to migrating birds and bats, and the diverter can be spaced a greater distance compared to prior art devices, reducing time and cost of installation. Stainless steel material is utilized for all moving parts of the swivel assembly to make them resistant to rust and corrosion by the elements. 
     While this invention has been described as having preferred design, it is understood that it is capable of further modification, uses and/or adaptations following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features set forth, and fall within the scope of the invention or the limits of the appended claims.