Abstract:
An internally expanding and locking apparatus for installing inside the pipe stub of a typical outdoor lighting pole and expanding with locking teeth to grasp the inner walls of the pipe stub, the apparatus including a swivel base, a clamp screw inserted through the swivel base, a ramp nut passing over the clamp screw so as to be positioned offset from the swivel base, and a mounting nut threadably installed on the clamp screw and configured to engage the ramp nut so as to control the position of the ramp nut relative to the swivel base as the clamp screw is rotated during use of the pipe mounting apparatus.

Description:
RELATED APPLICATIONS 
   This application claims priority and is entitled to the filing date of U.S. Provisional application Ser. No. 60/716,206 filed Sep. 12, 2005, and entitled “Luminaire Mounting System with Single Tightener.” The contents of the aforementioned application are incorporated by reference herein. 
   INCORPORATION BY REFERENCE 
   Applicants hereby incorporate herein by reference any and all U.S. patents and U.S. patent applications cited or referred to in this application. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   Aspects of this invention relate generally to an apparatus and method for mounting a device to a pole or other structure having an existing pipe stub, and more particularly to such an apparatus and method for attaching luminaries to new or existing poles for particular lighting applications. 
   2. Description of Related Art 
   Pre-existing light poles or other supports and the pipes or pipe stubs extending therefrom on which a particular luminaire mounting is to be attached are known in the art to have varying diameters, varying pipe wall thickness and varying materials such as steel or aluminum. Each pipe may also have a different surface coating, such as zinc, paint, powder coat, and anodizing or natural corrosion. In the case of an outdoor lighting application, the mounting attachment must conform to known criteria required to sustain harsh weather and hurricane force winds. The integrity of this mounting attachment is important in order to secure the luminaire to the manufacturer&#39;s specified tightness and central registration for conformance to predetermined performance and light pattern requirements. 
   More particularly, as is known in the art, there can be variations from one pipe size to another so that half-inch or larger gaps must be accounted for in the pre-existing pipe mounting diameters, thus the attachment means must seal the excess opening between the luminaire and the pipe from insects, small animals and weather intrusion. In the typical application, electrical wires also pass through the pipe stub to connect within the luminaire after the luminaire is secured to the fitting, creating other mounting and sealing challenges. 
   Luminaire mounting systems of the prior art have shown several methods to attach to the pipe stub. One type may have a simple pipe flange fitting with setscrews spaced equally apart in at least three positions around the circumference of the coupling to be tightened onto the protruding pipe stub. Another type may have one or more compression clamps internal to the luminaire housing that straddle the pipe to compress it against a saddle-shaped base, which requires removal of or opening of an access door to expose the bolts within the clamp and saddle mechanism. And yet another known mounting system is a docking station concept that allows a plug and socket to be secured to the pipe before the luminaire is mounted in order to ensure that attachment to the pipe stub is correctly meeting specification without the nuisance of holding and balancing the luminaire while tightening all bolts to equal tension. 
   In the known prior art mounting systems herein described, the installer is generally required to hold the luminaire or luminaire mounting base level and stationary while alternately tightening each of the mounting bolts. As in the case of a luminaire with three or more bolts spread around a flange, they are all behind the luminaire from the position of the installer, and in order to keep the pipe centered within the flange, each bolt must be tightened uniformly from behind the luminaire while the installer holds the luminaire in the correct position with his other hand. In a luminaire that must be opened to access the clamp mechanism, there can typically be four clamp bolts that must be alternately tightened to equal tension in order to keep the pipe centered within the clamp. 
   Each of these previously described installation scenarios in the exemplary context of outdoor pole lighting is an awkward situation for an installer in a lift or bucket truck and as a result sometimes the installation is completed hastily without properly and evenly securing the mount. The integrity of the mounting attachment is the basis of wind load conformance testing, and is that which secures the luminaire to the pole and pipe stub mount during harsh weather such as hurricane force winds. The inconsistency in mounting integrity is demonstrated in practice with the prior art systems when moderate winds can weaken or remove some luminaires and not others despite wind tunnel test results showing sustainability. Integrity may be further compromised if the clamp forces are not even or centered on the pipe to the manufacturer&#39;s recommendations. Luminaire attitude or vertical angle adjustment is affected by the pipe stub position in the clamp method or flange screw methods in each of the aforementioned systems; therefore, when a non-zero angle of luminaire attitude adjustment is set, that can and often does adversely affect installation integrity. 
   The prior art described above teaches luminaire mounting systems that can be installed in various pipes and pipe stubs, but does not teach an apparatus and method including a single tightening point toward the front of the luminaire and thus facing in the direction of the installer and such a system that inherently closes the pipe against the luminaire regardless of the pipe size so as to prevent the intrusion of insects, small animals and weather. Aspects of the present invention fulfill these needs and provide further related advantages as described in the following summary. 
   SUMMARY OF THE INVENTION 
   Aspects of the present invention teach certain benefits in construction and use which give rise to the exemplary advantages described below. 
   Aspects of the present invention are generally directed to an internally expanding and locking mechanism that installs inside of the pipe stub of a typical outdoor lighting pole and expands with locking teeth to grasp the inner walls of the pipe mast or stub. An advantage taught by the present invention is the single point tightening method that permits the installer to relatively easily support the luminaire while securing it to the pipe stub or mast in a way that consistently conforms to mounting tension specification and thereby comply with standard wind load testing regardless of the pipe diameter and wall thickness. Another advantage of the present invention is the expansible nature of the mechanism that inherently provides a proper fit and registration to all pipe sizes ordinarily found in the field. Yet another advantage of the present invention is the pipe closure feature of the expanding mechanism that also inherently protects the luminaire from insect and weather intrusion for virtually any of the available pipe sizes, and which also adds further mechanical rigidity to the mounting. While the exemplary embodiment of the invention is shown and described in the context of mounting a luminaire to a conventional outdoor lighting pole, it will be appreciated by those skilled in the art that numerous other mounting applications, both of the pipe or other support and of the device to be mounted, are possible in the present invention without departing from its spirit and scope. 
   Other features and advantages of aspects of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of aspects of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings illustrate aspects of the present invention. In such drawings: 
       FIG. 1  is an exploded perspective view of an exemplary embodiment of the pipe mounting apparatus of the invention; 
       FIG. 2  is a side view thereof showing the pipe mounting apparatus inserted within an exemplary pipe stub; and 
       FIG. 3  is a side view thereof showing the pipe mounting apparatus secured within the exemplary pipe stub. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The above described drawing figures illustrate aspects of the invention in at least one of its exemplary embodiments, which are further defined in detail in the following description. 
   In  FIG. 1  there is illustrated an exploded view of an exemplary embodiment of the pipe mounting apparatus  10  of the present invention. The pipe mounting apparatus generally comprises four primary components, including a ramp nut  11  that abuts a swivel base  17  when both have clamp screw  18  inserted through their respective center holes. The assembly of these components is held intact with mounting nut  12  when threaded onto the threads  19  that are cut into the end of the clamp screw  18  opposite the swivel base  17 , the mounting nut  12  being seated and keyed within a corresponding recess in the free end of the ramp nut  11 . It should be clear to the reader that with the mounting nut  12  so threaded on the clamp screw  18  and secured against rotation by being seated within the ramp nut  11 , more or less turning of the clamp screw  18  with its threads  19  engaging the mounting nut  12  will adjust the distance between the ramp nut  11  and the swivel base  17 , more about which is said below in connection  FIGS. 2 and 3  showing the pipe mounting apparatus  10  in use. Those skilled in the art will appreciate that the size and configuration of the various components making up the pipe mounting apparatus, and hence the apparatus itself, may vary depending on the application, or the particular size or size range of the pipe or other support in or to which the luminaire or other device is to be mounted, such that the components shown and described are to be understood as being merely exemplary and that numerous other sizes and configurations of the pipe mounting apparatus may be practiced without departing from the spirit and scope of the invention. Moreover, again, while the exemplary embodiment of the invention is shown and described in the context of mounting a luminaire to a conventional outdoor lighting pole, it will be appreciated by those skilled in the art that numerous other mounting applications, both of the pipe or other support and of the device to be mounted, are possible in accordance with the principles of the present invention. 
   In  FIG. 1  there are further illustrated grooves  13   a  cut into the ramp nut  11 . In the exemplary embodiment there are to be a total of three (3) grooves  13   a , with two on the rear side not in view, though those skilled in the art will appreciate that the number of such grooves may vary within the scope of the invention. Each groove  13   a  aligns with a similar and opposite groove  13   b  cut into the adjoining swivel base  17 . As is also shown in  FIG. 1 , a trapezoidal or wedge-shaped gripper  14  is configured for insertion within each respective pair of grooves  13   a ,  13   b . The gripper  14  configuration is illustrated with a plurality of raised bumps or ribs  15  along its front or topside, or its side opposite the ramped or angled edges of the gripper  14  configured to seat in and engage the grooves  13   a ,  13   b  formed in the respective ramp nut  11  and swivel base  17 , the raised ribs  15  thus forming serrations therebetween. Also shown is a notch  16  in or about the center of the front or topside edge of the gripper  14 . The purpose of the ribs  15  and notch  16  of each gripper  14  will be better understood in the context of  FIGS. 2 and 3  illustrating the pipe mounting apparatus  10  in use. Those skilled in the art will once more appreciate that while in the exemplary embodiment there are three such grippers  14  inserted into the corresponding three sets of grooves  13   a ,  13   b , such that the radially outward mounting forces or points of engagement with the inside surface of a pipe stub or other structure are roughly one hundred twenty degrees (120°) apart, two grippers or more than three grippers of varying geometry, and corresponding grooves in the ramp nut and swivel base, are also possible in the present invention. Specifically, while the exemplary gripper  14  is shown as having four ribs  15  substantially symmetrically arranged in pairs about a single central notch  16 , it will be further appreciated that numerous other configurations of the gripper, and its front or topside edge, particularly, to suit a particular application or pipe mount surface are possible without departing from the spirit and scope of the invention. 
   With continued reference to  FIG. 1 , there is shown a flange  20  affixed to the clamp screw  18  through which tightening or loosening of the seated mounting nut  12  threadably installed on the clamp screw  18  is affected. One or more holes  21   a  may be incorporated in the flange  20  for inserting a tool to facilitate more leverage in order to increase torque when tightening or loosening the mounting nut  12 . In the exemplary embodiment, the flange  20  also has knurled ridges  21   b  or the like to facilitate initial finger tightening without tools, further easing installation. Also shown is a small cone  22  and a large cone  23  affixed to the swivel base  17 , which cones will also be better understood in connection with the pipe mounting apparatus  10  in use, as described below and shown in  FIGS. 2 and 3 . 
   There is also illustrated in the exemplary pipe mounting apparatus  10  of  FIG. 1  a swivel end cap  24  as a means to attach the swivel base  17  to a luminaire (not shown). In the exemplary embodiment, two positions for the upper fasteners  25  and two positions for the lower fasteners  26  are shown to facilitate attachment between the swivel base  17  and the end swivel cap  24 . It should be clear to those skilled in the art that the upper fasteners  25  may be configured to enter through round holes  27  so as to offer little or no lateral movement of the swivel end cap  24 , while the lower fasteners  26  may be configured to enter through slots  28  in the end swivel cap  24  so as to allow for a range of movement of the swivel end cap  24 , the swivel end cap essentially pivoting on the upper fasteners  25  as the lower fasteners  26  ride in slots  28 , by which the luminaire (not shown) may be adjusted on at least one axis of movement. As such, it will be appreciated by those skilled in the art that either or both sets of fasteners  25 ,  26  may utilize slotted mounting holes to achieve some additional or different degree of adjustment of the end swivel cap  24 , and hence the luminaire or other such device to be mounted. Likewise, those skilled in the art will also appreciate that when no attitude adjustment of the luminaire or other mounted device is desired, the end cap  24  may be omitted in its entirety and the swivel base  17  may attach directly to such device with fasteners similar to those previously described. It will be appreciate that in any such alternative embodiment, and depending on the application, the fasteners, denoted in  FIG. 1  simply by arrows, may include any fastening means now known or later developed, including but not limited to screws, bolts, pins and the like. 
   Turning now to  FIG. 2 , there is shown the exemplary embodiment of the pipe mounting apparatus  10  inserted within a pipe stub  31 , shown partially cut away. Preferably, the clamp screw  18  is tubular and thus provides a path for the electrical wires  33  originating from within the pole (not shown) and pipe stub  31  to pass through the pipe mounting apparatus  10  and enter the luminaire (not shown) or other device to be mounted and electrically powered. In  FIG. 2  it is again shown that the mounting nut  12  is attached to the clamp screw  18  and drawn inside of the corresponding recess formed in the ramp nut  11  that holds the swivel base  17  intact as an assembly. In the view of  FIG. 2 , now an upper and lower gripper  14  are shown, with a third gripper not shown but present on the hidden side of the ramp nut  11  and swivel base  17 . Again, those skilled in the art will appreciate that three grippers  14  is merely illustrative and that the invention is not so limited. As also shown in  FIG. 1 , each gripper  14  has a notch  16  that in  FIG. 2  is shown with an o-ring  34  that holds intact and biases radially inwardly the plurality of grippers  14  that may be incorporated. Those skilled in the art will appreciate that any other mechanical means now known or later developed for holding and/or biasing the two or more grippers  14 , including but not limited to a circular coil spring or spring ring clip or any such element having elasticity, may be employed in the present invention to hold the plurality of grippers  14  in place. It will also be appreciated that in an alternative embodiment the mounting nut  12  may be omitted and the ramp nut  11  may itself be threaded to receive the clamp screw. 
   With continued reference to  FIG. 2 , it is shown that when the pipe mounting apparatus  10  is inserted into the pipe stub  31 , the pipe stub walls  32  substantially abut the flange cone  23 , which closes the gap between the pipe wall  32  and the swivel base  17 , thereby preventing or minimizing intrusion of any unwanted elements. It will be appreciated that a smaller pipe would abut the smaller flange cone  22 , thereby accomplishing end closure for an even smaller pipe. It will thus be appreciated by those skilled in the art that a variety of shapes, configurations and numbers of such flange cones can be adapted for other applications or pipe sizes. 
   Referring now to  FIG. 3 , there is now shown the pipe mounting apparatus  10  with the mounting mechanism inside the pipe stub  31 . Specifically, the ramp nut  11  has been drawn toward the swivel base  17  by a distance represented by arrow  41 , which movement naturally compresses each gripper  14  in its respective grooves  13   a ,  13   b , thereby raising each gripper  14  on all sides of the ramp nut  11  and the swivel base  17  as each gripper  14  rides substantially radially outwardly as its ramped or angled inside edges engage and slide along the respective groves  13   a ,  13   b . As shown in  FIG. 3 , once the mounting nut  12  has been substantially tightened through its travel along the threads  19  of the clamp screw  18  as the screw  18  is rotated by operation of the flange  20 , the outwardly projecting ribs  15  formed on the along the outside edge of each gripper  14  now contact the pipe wall  32  substantially in the locations  42 . It will be further appreciated that as the clamp screw  18  is tightened, the flange cone  22  or flange cone  23  is drawn closer to the pipe wall  32 , thereby further ensuring a seal to the pipe opening and adding yet more mechanical support for the pipe mounting apparatus  10  within the pipe stub  31 . It is also apparent from  FIG. 3  that the electrical wiring  33  integrity is not compromised during the mounting process, as the wiring  33  is kept a safe distance from any mechanical compression because the clamp screw  18  forms a continuous tubular conduit. Once again, it will be appreciated by those skilled in the art that numerous other configurations of the pipe mounting apparatus and the corresponding means by which it is used are possible without departing from the spirit and scope of the invention. 
   While aspects of the invention have been described with reference to at least one exemplary embodiment, it is to be clearly understood by those skilled in the art that the invention is not limited thereto. Rather, the scope of the invention is to be interpreted only in conjunction with the appended claims and it is made clear, here, that the inventors believe that the claimed subject matter is the invention.