Abstract:
A bird anti-perching device is described having a rotatable cylindrical member extending between two support members and capable of rotating freely if a bird lands thereon, thereby to form an unstable perch. The device can be attached to the ledge of a balcony in a number of ways to prevent birds from alighting on the balcony.

Description:
FIELD OF THE INVENTION 
     This invention relates to bird anti-perching devices. More particularly this invention relates to a bird anti-perching device for discouraging birds from perching on a ledge or other surface. 
     BACKGROUND OF THE INVENTION 
     Home owners and apartment dwellers often have difficulty with unwanted birds which alight on surfaces such as ledges, railings or fences and leave excrement when they leave. 
     It is possible to continually clean the affected surface but this does not address the cause of the problem, namely, unwanted birds. 
     One attempt to solve the problem can be found in U.S. Pat. No. 5,755,179 which utilizes a rectangular flat plate suspended by a rod. The flat plate can rotate and may throw the bird off the plate and prevent it from landing. The plate is positioned so that it rotates eccentrically around its axis. 
     Problems with this approach have become apparent because birds can perch on a flat plate if they have a second surface on which to balance a foot. 
     It would be advantageous to provide an anti-perching device which prevents a bird from getting a second foothold. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to prevent a bird from perching on a ledge or other surface. 
     Another object of the invention is to provide for a product which can be easily attached to the ledge or other surface. 
     Accordingly, there is provided a bird anti-perching device for discouraging birds from perching on a surface, comprising two spaced-apart support members and a rotatable cylindrical member extending between said two support members and capable of rotating freely if a bird lands thereon, thereby to form an unstable perch. 
     According to one embodiment of the invention the support members each have a pin which is respectively inserted in the center of one end of the cylindrical member and another portion which essentially clamps the cylindrical member parallel to the ledge such that it can rotate freely. 
     The cylindrical member is positioned so that there is not sufficient room for a bird to perch between the cylindrical member and the railing. 
     It will be understood that the cylindrical member could be of hollow, solid or other construction. 
     The cylindrical member could be made of a wide variety of materials. For example, the member could be made of wood, plastic, metal or some other material. 
     The support members could have a second pin immediately opposite the first pin so that a series of cylindrical members could be positioned along a railing. 
     In some cases it is not possible to use proper clamps to affix the cylindrical member to the ledge and some form of clamping utilizing VELCRO (trade mark) material can be used. 
     It is also possible to permanently affix the cylindrical member to the ledge through mounted supports instead of using clamps. 
     Further, the cylindrical member can have internal longitudinal reinforcement to reduce bending of the tube of the cylindrical member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the invention will now be described, by way of example, with reference to the following drawings in which: 
     FIG. 1 is a side view of one embodiment of the invention. 
     FIG. 2 is a perspective view of a support member shown in FIG.  1 . 
     FIG. 3 is an end of a second type of support member. 
     FIG. 4 is an end view to illustrate use of a different type of support member. 
     FIG. 5 is a perspective view of a still further modified embodiment of the support member. 
     FIG. 6 is an end view of the support member shown in FIG. 5 taken in the direction of arrow A in FIG.  5 . 
     FIG. 7 is an exploded perspective view of a portion of the cylindrical member and internal reinforcement member or element. 
     FIG. 8 is an elevational view, partly in section, of the cylindrical member of FIG. 7 assembled. 
     FIG. 9 is an elevational view, partly in section, of the anti-perching device of FIGS. 5-8 assembled and on a balcony railing. 
     FIG. 10 is an end view, partly in section, showing the device of FIGS. 5-8 on a different railing structure. 
     FIG. 11 is a perspective view of another embodiment of a support member of the invention associated with a railing having spaced vertical posts. 
    
    
     The same reference numerals are used for like parts throughout. 
     DETAILED DESCRIPTION 
     Referring to FIG. 1, a rotatable cylindrical member  2  is supported by two spaced-apart support members  4  and  6  and so as to be capable of rotating freely if a bird lands thereon. In this way an unstable perch is provided. 
     The cylindrical member  2  is supported on support members  4  and  6  by means of centrally located axle rods  8  and  10 . 
     In FIG. 2, a support member  4  is shown in perspective view to be a clamp in the shape of an inverted U with an upstanding or vertical portion  12  for the axle rod  8 . The depending legs  14  and  16  of the U-shaped support member  4  are each drilled in their approximate centre to form a respective internally threaded hole through which an externally threaded rod  18  passes. On its inner end each threaded rod is provided with a plate  20  and on its outer end with a handle portion  22 . 
     In use, the support members  4  are fitted over, for example, the ledge  24  of a balcony, (FIG.  1 ), of an apartment and the handles  22  turned so that the support members  4  and  6  clamp on the ledge  24 . The cylindrical member  2  is thus located above the surface of the ledge  24  at such a position that a bird cannot alight between the cylindrical member  2  and the surface of the ledge  24 . 
     In FIG. 3, a part of a second embodiment is shown. A support member  4  is made with an axle rod protrusion or pin  8  on both sides of the vertical portion  12  so that adjacent intermediate tubes can be supported by one support or clamp. 
     In FIG. 4, a still further embodiment is shown in which the support members  4  and  6  are L-shaped in side view and provided with bolts  26  to fasten them to the top surface of the ledge, (usually formed of concrete). FIG. 4 also shows support members  4  and  6  with pins on both sides to support adjacent cylindrical members  2 ′ partially shown in dotted lines. 
     FIGS. 5-10 illustrate a still further and preferred embodiment of the invention. Turning to FIGS. 5 and 6, support  30  comprises L-shaped bracket portion  32  and inverted U-shaped portion  34  which portions are fastened or secured together at  36  by any suitable means, such as spot welding. Upstanding or vertical leg  40  of L-shaped bracket portion  32  has aperture  42  through which pin  44  passes. Pin  44  is secured to leg  40  through a press fit connection and may be made of cylindrical spring steel to facilitate such press fit connection. However, any other means of securing pin  44  to leg  40  is contemplated and appropriate. Bight  50  of U-shaped portion  34  is secured inwardly from end  52  of horizontal leg  54  of bracket portion  32 . Downwardly extending legs  56 ,  58  of U-shaped portion  34  each have apertures  60  for passage of the threaded shank  62  of thumb screw  64 , threaded shank  62  being adapted for threaded cooperation with speed nut  66 . More particularly, speed nut  66  is a U-shaped clip  68  which attaches over the lower ends  70 ,  72  of legs  56 ,  58  and has holes in alignment with aperture  60 , the inside hole  74  of clip  68  being threaded and adapted to provide a threaded connection with thumb screw shank  62  in known fashion. A plastic cap  80  is screwed onto the inner end  84  of thumb screw  64 . 
     Turning to FIGS. 7 and 8, there is shown a cylindrical hollow tube  90  of plastic material with circular end caps  92 ,  94  adapted to be secured by suitable glue or other means to open ends of tube  90 , (only end cap  92  being shown in FIG.  7 ). End caps  92 ,  94  have coaxial bores  98 ,  100  into which bushings or bearings  102 ,  104  are respectively secured, bushings  102 ,  104  being preferably of a material having a low coefficient of friction, such as a polyacetal plastic. Tube  90  is preferably of an acrylic plastic material. Bushings  102 ,  104  each have flange  106  and cylindrical portion  108  for securement to cap  92 ,  94  and in bores  98 ,  100  thereof as seen in FIG.  8 . Bores  106 ,  108  in bushings  102 ,  104  are sized to permit free rotation of tube  90  on pins  44 . 
     Preferably, reinforcing element  110  is of a light material such as aluminum, in the form of a “T” or an inverted “T” adapted to be inserted within tube  90  to provide longitudinal reinforcement to the tube  90  between supports  30 . This allows for use of longer tubes  90  between supports  30  as well as preventing the tube sagging or bending over time and/or under the weight of a bird or several birds on tube  90 , which could cause the cooperation of pins  44  and bushings  102 ,  104  to become misaligned and bind and lessening free rotation of tubes  90  on pins  44 . Element  110  has cross piece  112  and leg  114 , leg  114  having tapered ends  116 ,  118  so that the T-element does not interfere with pins  44  extending into tube  90  through caps  92 ,  94 . T-member is of a size to be relatively easily inserted into tube  90  but with the edges of cross pieces  112  and leg  114  in contact with the interior wall of tube  90 . Element  110  is similar to a false ceiling bracket known in the building trade. 
     FIG. 9 (and also FIG.  6 ), illustrate, partly in section, a railing  120  on a balcony  124  to which supports  30  and tube  90  have been assembled. It will be appreciated that the configuration of supports  30  allows the vertical leg  40  to be close to the outer edge  126  of the balcony railing. Further, one intermediate bracket  30  can serve to support two adjacent tubes  90  and  90 ′. 
     FIG. 10 illustrates support  30  assembled to a balcony railing which has an upper horizontal rail  130  wider than the vertical support  132 . Thumb screws  64  with shank  62  can be long enough, as shown on the left side of the railing in FIG. 10, to provide adequate clamping of support  30  to the vertical support  132  of railing  130 , but if necessary, a block  140  of wood or other material can be inserted as shown in dotted lines on the right side of the vertical railing support  132 . Still further, it will be appreciated that U-shaped portion  34  could be constructed whereby the bight  50  is wider and thumb screws  64  and shank  62  located on the legs such that they engage the sides  134  of rail  130 . 
     In a particularly preferred aspect of the support  30 , acrylic tube  90  may be 1-½″ to 2″ in diameter and 6 feet in length with an aluminum T-member inserted into tube  90  and of a length about ¾″ short of each end cap. Alternatively, as shown in FIGS. 7 and 8, tapered ends  116 ,  118  of the T-member can be provided. 
     As shown in FIG. 5, support  30  has U-shaped bracket  34  located inwardly of end  52  of horizontal leg  54  of L-shaped portion  32 . This construction provides for greater stability to the support  30  and lessens any tendency for the support to rotate or turn due to weight on the tubes, particularly when used as an end support as shown in the right side of FIG. 9 adjacent edge  126 . 
     Although supports  30  are preferably of coated steel, it will be apparent that supports  30  could be made of a plastic. Turning to FIG. 11, an L-shaped plastic support member  140  with relatively wide horizontal leg  142  and vertical leg  144  is shown, vertical leg  144  having pins  146  and being somewhat triangular in shape. 
     The balcony railing  150  is of the type having a relatively wide upper railing  152  supported by spaced vertical uprights  154 ,  156 . 
     Flexible plastic strap  160  is secured to the upper surface of horizontal leg  142  and has ends  166 , 168 , (shown in dotted lines), with fastening means such as hook and loop fabric fastener means. The width and length of horizontal leg  142  relative to the width of railing  152  provides suitable lateral and horizontal support to support member  140  when strap  160  is secured to railing  152 . Although a single plastic strap  160  is shown, more than one strap is contemplated and may be suitably used as an alternative to the illustrated embodiment. 
     It will be readily apparent to a person skilled in the art that a number of variations and modifications can be made without departing from the true spirit of the invention which will now be pointed out in the appended claims.