Abstract:
An adjustable tamper-resistant overhead mounting system for a projector. The system includes brackets attachable to the projector and a suspension member attached to an overhead structure. At least one tamper resistant fastener is used at each connection of the brackets, the projector and the suspension member, to deter theft and tampering. The arrangement of the brackets may enable easy adjustable positioning of the projector about pitch, roll and yaw axes. The projector may also be enclosed in an enclosure system to protect against contact by foreign objects. The enclosure is adapted to be installable without removing the projector or otherwise disturbing the mounting system.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/462,391 filed Apr. 11, 2003, the same being hereby fully incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to mounting systems for visual projectors, and more specifically, to tamper resistant mounting systems for projectors. 
     BACKGROUND OF THE INVENTION 
     Visual projection systems are commonly used for displaying and presenting visual information to groups of people. Such visual projection systems typically include a projector unit and a projection screen. 
     In spaces such as classrooms, conference rooms, and public assembly halls, where the space is often used for presentations, it is common that the projector unit be installed as a more or less permanent fixture in the space. Often, the projector will be suspended from an overhead structure, such as a building floor/ceiling assembly or roof, in order to give the projector an unobstructed projection path and to protect it from damage by inadvertent contact. It is generally desirable that the mount be adjustably positionable over a wide range of positions to enable proper aiming and focusing of the projector. 
     Projectors, particularly LCD, CRT, and DRP projectors designed for frequent use in a setting such as described above are quite expensive. In addition, the spaces where the projector is installed may be unsecured for periods of time or left unattended. Consequently, a problem is that projector units are attractive targets for theft, vandalism and other tampering. 
     Another problem is that in some multi-use spaces, such as gymnasiums, the projector unit can be exposed to the possibility of unintentional or intentional contact by objects such as balls or other similar flying objects. In other multi-use spaces such as hotel conference facilities, the projector unit may be subject to contact by ladders, maintenance person lifts and the like during set-up and take-down of exhibits and booths. 
     What is needed in the industry is an easy-to-use adjustable ceiling mounted projector mounting system that substantially alleviates these problems. 
     SUMMARY OF THE INVENTION 
     The present invention is an adjustable tamper-resistant overhead mounting system for a an LCD, CRT or DCP projector that addresses the aforementioned need in the industry. The adjustable mount bracket of the present invention includes brackets attachable to the projector and a suspension member attached to an overhead structure. At least one tamper resistant fastener is used at each connection of the brackets, the projector and the suspension member, to deter theft and tampering. The brackets enable inverted mounting of the projector from the ceiling structure of a space. The arrangement of the brackets may enable easy adjustable positioning of the projector about pitch, roll and yaw axes. The projector may also be enclosed in an enclosure system to protect against contact by foreign objects. The enclosure is adapted to be installable without removing the projector or otherwise disturbing the mounting system. 
     A tamper resistant mounting system for adjustably attaching a visual projection device to a suspension member that is fixedly attached to an overhead structure includes a device interface bracket attachable to the projection device with at least one tamper resistant fastener. The device interface bracket is operably coupled to a suspension member interface portion. The suspension member interface portion is attachable to the suspension member with at least one tamper resistant fastener and is secured to the device interface bracket with at least one tamper resistant fastener. 
     The mounting system may further include an enclosure adapted to enclose the visual projection device. The enclosure includes an integral surround portion having a top, a bottom, a pair of opposing sides, and a pair of open ends. A pair of end caps is provided to fit over and close the open ends. Each of the end caps is secured to the surround portion with at least one tamper resistant fastener, and enclosure is secured to the tamper resistant mounting system with at least one tamper resistant fastener. At least one lock and an elongate locking bar may be provided to secure the end caps on the enclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a projector and tamper resistant mounting system according to the present invention; 
         FIG. 2  is a partial perspective view of a tamper resistant adjustable mount bracket according to present invention; 
         FIG. 3  is an exploded view of the adjustable mount bracket of  FIG. 2 ; 
         FIG. 4  is a partial exploded view of the adjustable mount bracket on a projector, depicting the locations of tamper resistant fasteners; 
         FIG. 4A  is a perspective view of a hex-pin tamper resistant fastener; 
         FIG. 4B  is a perspective view of a Phillips-pin tamper resistant fastener; 
         FIG. 4C  is a perspective view of a one-way slotted tamper resistant fastener; 
         FIG. 4D  is a perspective view of a Torx® pin tamper resistant fastener; 
         FIG. 4E  is a perspective view of a TP3® tamper resistant fastener; 
         FIG. 4F  is a perspective view of Tri-Wing® tamper resistant fastener; 
         FIG. 4G  is a view of a pair of tamper resistant spanner nuts; 
         FIG. 5  is a perspective view of a connection of one embodiment of a suspension member to a floor/ceiling or roof assembly of a structure; 
         FIG. 6  is a side elevation view of an alternative suspension member embodiment with a connection to a floor/ceiling or roof assembly of a structure; 
         FIG. 7  is a front elevation view of the embodiment of  FIG. 6 ; 
         FIG. 8  is a perspective view of a tamper resistant mounting and enclosure system according to the present invention; 
         FIG. 8A  is a front perspective view of the enclosure; 
         FIG. 8B  is a rear perspective view of the enclosure; 
         FIG. 9  is a perspective view of the top of the enclosure at an intermediate step during installation; 
         FIG. 9A  is an elevation view of a clamp for attaching the enclosure to a suspension member; and 
         FIG. 9B  is a plan view of the clamp of  FIG. 9A . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A tamper resistant visual projector mounting system  10  generally includes an adjustable bracket  12  and a suspension member  14 . 
       FIG. 2  designates, for reference purposes, the relative directions of x-y-z coordinates as applied to the mounting system  10 . Any reference herein to rotation about an x-axis or “roll” movement, a y-axis or “pitch” movement, or a z-axis or “yaw” movement, relates to these coordinate axes. The y-axis is oriented fore-and-aft relative to a visual projector attached to the mounting system, the z-axis is vertical and the x-axis is perpendicular to the z-axis and the y-axis, and is oriented laterally from side-to-side of the projector. 
     Adjustable bracket  12  generally includes device interface bracket  18  and suspension member interface  20 . Device interface bracket  18  includes planar portion  22  and a pair of spaced-apart upwardly projecting flanges  24 . Each flange  24  has a central hole  26  and a pair of opposing curved slots  28  surrounding hole  26 . 
     Suspension member interface  20  generally includes an upper portion  30  and a lower portion  32 . Lower portion  32  is dimensioned so as to fit within upper portion  30 . Upper portion  30  has flat portion  34  and a pair of downwardly projecting side portions  36 . Flat portion  34  has a central aperture  38  with interior threads  40  for receiving a suspension member  14  in the form of a threaded pipe hanger  42 . A plurality of curved slots  44  for receiving a suspension member  14  in the form of rod hangers  45  are arranged symmetrically on either side of central aperture  38 . Each curved slot  44  has a radius of curvature  46  with a center  48  generally corresponding with the center  50  of central aperture  38 . Each side portion  36  has an aperture  52  with a pair of slots  54  arranged symmetrically on either side of aperture  52 . 
     Lower portion  32  has a flat portion  56 , upwardly directed sides  58 , and upwardly directed ends  60 . Sides  58  are spaced apart so as to fit between side portions  36  of upper portion  30  with outer surfaces  62  confronting inner surfaces  64  of side portions  36 . Similarly, ends  60  are spaced apart so as to fit between flanges  24  of mounting plate  18 . Each side  58  has a central threaded hole  66  located so as to correspond with aperture  52  when lower portion  32  is disposed within upper portion  30 . Similarly, threaded holes  68  are located so as to correspond with slots  54 . Threaded fastener  70 , having a washer  72 , extends through aperture  52  and threads into threaded hole  66  in each of sides  58 , so that upper portion  30  is rotatably attached to lower portion  32  about an axis, annotated A—A, extending through apertures  52 . Threaded fastener  74  and tamper resistant threaded fastener  75 , each with a washer  76 , extend through each of slots  54  and thread into threaded holes  68 . 
     Tamper resistant threaded fastener  75 , and any other tamper-resistant fastener or set-screw referred to herein, may be any of a wide variety of tamper resistant fastener head designs such as those depicted in  FIGS. 4A–4F , including the standard hex-pin design of  FIG. 4A , the standard Phillips-pin design of  FIG. 4B , and the one-way slotted design of  FIG. 4C , each of which is designed for installation and removal with a special tool having a limited availability to the general public. In addition to the standard tamper resistant fastener designs listed above, any other tamper resistant or security fastener may be suitably used, including unique proprietary designs such as the Torx® pin design of  FIG. 4D , made by the CamCar Division of Textron, Inc., the TP3® design of  FIG. 4E , made by Tamperproof Screw Co., Inc., and the Tri-Wing® design of  FIG. 4F , made by Phillips Screw Co. 
     When tightened, the head portion  78 ,  79 , of each fastener  74 ,  75 , compresses washer  76  against side portion  36 , thus enabling a frictional adjustment for fixing upper portion  30  in a selected rotational position relative to lower portion  32 . Once tightened, tamper resistant threaded fasteners  75  impede any attempt to separate lower portion  32  from upper portion  30  without the special tool for installing and removing the tamper resistant fasteners. 
     Although two tamper resistant fasteners  75  are depicted, one extending through each side portion  36 , it will be appreciated that one tamper resistant fastener  75  may used, and will impede tampering to a somewhat more limited degree. Similarly, if desired, additional tamper resistant fasteners  75  may be used in place of regular fasteners  74  if desired to provide additional impediments to tampering and theft. 
     Each end  60  of lower portion  32  has a central threaded hole  80  corresponding with central hole  26  in each flange  24  of device interface bracket  18 . A threaded fastener  82 , having a washer  84 , extends through central hole  26  of each flange  24 , and threads into threaded hole  80 , so that lower portion  32 , and suspension member interface  20 , is rotatably attached between flanges  24  about an axis, annotated B—B, extending through central holes  26 . Threaded fastener  86 , and tamper resistant threaded fastener  87 , each with a washer  88 , extend through curved slots  28  and thread into threaded holes  90  in ends  60 . As before, tamper resistant fastener  87  may be any suitable tamper resistant or security fastener, and one or any other number of tamper resistant fasteners  87  may be used as desired. When tightened, the head portion  92 ,  93 , of each threaded fastener  86 ,  87 , compresses washer  88  against flange  24 , thus enabling a frictional adjustment for fixing lower portion  32  in a selected rotational position relative to device interface bracket  18 . Once tightened, tamper resistant threaded fasteners  87  impede any attempt to separate suspension member interface  20  from device interface bracket  18  without the special tool for installing and removing the tamper resistant fasteners. 
     Device interface bracket  18  may be directly fastened to a projector  94  using fasteners  96 , and at least one tamper resistant fastener  98 , as depicted in  FIG. 2 . Again, tamper resistant fastener  98  may be any suitable tamper resistant fastener, and one or any other number of tamper resistant fasteners  98  may be used as desired. Device interface bracket  18  has a plurality of slots  100 . Each slot  100  is dimensioned so as to fit around the shank  102 ,  104 , of each fastener  96 ,  98 . 
     Threaded fasteners  96 ,  98 , may be partially threaded into holes  105  in projector  94 . Device interface bracket  18  may then be slid into position so that slots  100  are engaged around the shanks  102 ,  104 , of the fasteners  96 ,  98 . When the fasteners  96 ,  98 , are tightened, device interface bracket  18  is trapped between the head portions  106 ,  108 , of fasteners  96 ,  98 , and projector  94 , thereby securing device interface bracket  18  to projector  94 . Device interface bracket  18  may be removed from projector  94  by loosening fasteners  96 ,  98 , and sliding device interface bracket  18  so that slots  100  are disengaged from fasteners  96 ,  98 . It will of course be appreciated that additional security may be provided by substituting apertures for slots  100  so that device interface bracket  18  may be removed from projector  94  only by completely unthreading the fasteners, including tamper resistant fastener  98 . 
     As an alternative to direct fastening to a projector  94 , adapter plate  110  may be provided. Adapter plate  110  is secured to projector  94  with fasteners  112 , and at least one tamper resistant fastener  114 . Fasteners  112 ,  114 , extend through apertures  116  in adapter plate  110  and thread into threaded holes  118  in projector  94 . Adapter plate  110  has a plurality of upwardly projecting studs  120 , each with a nut  122 . The studs  120  are positioned so as to correspond with the location of slots  100  in device interface bracket  18 . Each nut  122  may have a knurled portion  124  so that the nut  122  may be threaded on the stud  120  by hand. In addition, adapter plate  110  has a threaded hole  126  in place of one stud  120 . Threaded hole  126  receives a tamper resistant fastener  128 . 
     Adapter plate  110  is secured to the projector  94  using fasteners  112  and tamper resistant fastener  114 . Nuts  122  are partially threaded onto studs  120 , and tamper resistant fastener  128  is partially threaded into threaded hole  126 . Device interface bracket  18  is then slid into position so that slots  100  are engaged with studs  120  and tamper resistant fastener  128 . Nuts  122  and tamper resistant fastener  128  are then tightened, securing device interface bracket  18  to adapter plate  110 , and thereby to projector  94 . 
     A suspension member  14 , in the form of threaded pipe hanger  42  may be secured to an overhead structure  130  by any suitable method. In one example, depicted in  FIG. 5 , overhead structure  130  is a floor/ceiling or roof assembly of a building, including parallel structural members  131 , which may be trusses, I-beams, wooden joists, or any other such structural member. A pair of channels  136  is positioned spanning adjacent parallel structural members  131 , and are fastened or welded in place. A hanger bracket  138  may then be fastened or welded to the channels  136 . Hanger bracket  138  has a plate portion  140  and a pipe nipple  142 , which is positioned so as to face downwardly. One end  144  of threaded pipe hanger  42  is threaded into pipe nipple  142 . The other end  146  of threaded pipe hanger  42  is threaded into central aperture  38  of suspension member interface  20 , so that adjustable bracket  12  and an attached projector  94  are suspended from the overhead structure  130  by threaded pipe hanger  42 . 
     A tamper resistant set screw  148  may be threaded into tapped hole  150  to stake threaded pipe hanger  42  in position and inhibit tampering or theft accomplished through unthreading of pipe hanger  42 . Similarly, pipe hanger  42  may be fixed within pipe nipple  142  by a tamper resistant setscrew  151  inserted through tapped hole  152 . Alternatively, particularly where the structural connection of pipe hanger  42  is above a concealing structure such as a suspended ceiling, pipe hanger may be fixed to pipe nipple  142  by welding, or with a fastener  152 A inserted through a hole  153  drilled through the threaded connection of pipe hanger  42  and pipe nipple  142 . 
     As an alternative, a plurality of suspension members  14  in the form of rod hangers  45  may be used to suspend adjustable bracket  12  and attached projector  94  as depicted in  FIGS. 6 and 7 . Again, channels  136  are arranged spanning parallel structural members  131 . Channels  136  have apertures  154  for receiving an end  156  of each rod hanger  45 . The rod hangers  45  may be formed from threaded rod stock. Each rod hanger  45  is attached to the channel with topside nut  158  and bottom side jam nut  160 . The other end  162  of each rod hanger  45  passes through one of curved slots  44 . Bottom side nut  164  and topside jam nut  166  secure the rod hanger  45  within each curved slot  44 . It will of course be appreciated that tamper resistant spanner nuts, such as depicted in  FIG. 4G , or any other type of tamper resistant nut, may be used for top side nut  158  or bottom side nut  164  to provide tamper resistant to the connection. 
     The operation of tamper resistant visual projector mounting system  10  may now be understood with reference to  FIGS. 1–4 . Device interface bracket  18  may be mounted on a projector  94  with front side  168  of the bracket  18  aligned with the front side  170  of the projector  94 . Suspension member interface  20  is attached to a suspension member  14 , which is in turn attached to an overhead structure as described above. When suspended as described, the A—A axis, about which upper portion  30  and lower portion  32  of suspension member interface  20  are rotatably attached, is oriented generally in the x-axis direction. Correspondingly, the B—B axis, about which device interface bracket  18  and suspension member interface portion  20  are rotatably attached, is oriented generally in the y-axis direction. 
     It will be appreciated that the connection between device interface bracket  18  and suspension member interface portion  20  described above enables selective relative rotational movement of projector  94  about the y -axis, thereby enabling a “pitch” adjustment for the projector  94 . Similarly, the connection between upper portion  30  and lower portion  32  of suspension member interface portion  20 , enables selective relative rotational movement of the projector generally about the x-axis, thereby enabling a “roll” adjustment for the projector  94 . Finally, the connection between suspension member interface  20  and suspension member  14  enables rotation of the projector about the z-axis, thereby enabling a “yaw” adjustment for the projector  94 . 
     At least one tamper resistant fastener is provided at the connection between projector  94  and device interface bracket  18 , at the connection between device interface bracket  18  and suspension member interface bracket  20 , and optionally between suspension member interface bracket  20  and suspension member  14 . These tamper resistant fastener connections provide a significant impediment to common everyday tampering or theft of the projector without unduly inhibiting usability of the projector by authorized users. 
     Mounting system  10  may also include a tamper resistant projector enclosure system  172  as depicted in  FIGS. 8–9B . The enclosure system  172  generally includes an integral surround portion  174 , end caps  176 ,  177 , and locking bars  178 . 
     Surround portion  174  has a top  180 , a bottom  182 , sides  184  and open ends  186 . Preferably, surround portion  174  is formed from a single piece of metallic material, such as light gauge steel, and is joined at a single longitudinal seam  188 . Openings  190  are provided for ventilation and heat rejection purposes. Top  180  has a slot  192  extending from proximate a center region  194  to one of the open ends  186 . Slot  192  is dimensioned so as to fit around pipe hanger  42  as will be further discussed hereinbelow. 
     End caps  176 ,  177 , fit over and cover each of open ends  186  of surround portion  174 . End cap  176  has a lens cutout portion  196 . An adjustably positionable cover panel  198  is provided to enable selective partial blocking of the cutout portion  196  to restrict access to the inside of the enclosure, while also providing flexibility for the different lens positions of projectors of various makes and models. 
     End caps  176 ,  177 , may be secured to surround portion  174  with tamper resistant fasteners  200  to inhibit unauthorized access to the inside of the enclosure. As described hereinabove, tamper resistant fasteners  200  may be any suitable standard or proprietary tamper resistant or security fastener. Additionally, one or more tamper resistant fasteners may be used to secure cover panel  198  to end cap  176 . 
     For additional security, end caps  176 ,  177 , may be locked in place on surround portion  174  with one or more locking bars  178 . Each locking bar  178  has a hooked end  202  and a straight end  204 . Straight end  204  has an aperture  206  for receiving a lock  208 . End cap  176  has engaging structures  210  in the form of apertures  212  for receiving the hooked end  202  of locking bars  178 . End cap  177  has corresponding slots  214 , for receiving straight ends  204  of locking bars  178 . 
     In operation, with end caps  176 ,  177 , in place on surround portion  174 , the straight end  204  of each locking bar  178  is inserted through aperture  212  and slot  214 , so that straight end extends through slot  214  outside the enclosure and hooked end  202  is engaged in aperture  212 . Hooked end  202  is hooked over the periphery  216  of end cap  176 . In this position, aperture  206  is just outside the enclosure proximate the outside surface  218  of end cap  177 . Lock  208  may then be locked through aperture  206 , thereby inhibiting withdrawal of locking bar  178  and securing end caps  176 ,  177 , on surround portion  174 . 
     The tamper resistant projector enclosure system  172  may be installed to enclose a projector  94  that is already suspended from an overhead structure without demounting the projector as depicted in  FIG. 9 . As previously described, slot  192  is dimensioned so as to fit around a suspension member  14 , such as pipe hanger  42 . With end cap  176  removed, slot  192  has an open end  220 , enabling surround portion  174  to be slid over projector  94  with suspension member  14  in slot  192 . Surround portion  174  may then be secured to adjustable bracket  12  with a tamper resistant fastener  222 . End cap  176  may then be secured in place on surround portion  174 , completing the enclosure. 
     A clamp  224  may be fastened around pipe hanger  42  as depicted in  FIGS. 9A and 9B  as an alternative for securing surround portion  174  to the mounting system  10 . Clamp  224  has a pair of clamping members  226 ,  228 , each with an arcuate shaped pipe interface surface  230 ,  232 . Clamping members  226 ,  228 , are fastened together with fasteners  234  disposed on either side of pipe interface surfaces  230 ,  232 . Fasteners  234  may be secured in place with tamper resistant nuts  235 , which may be those depicted in  FIG. 4G  or any other tamper-resistant nut. 
     In operation, clamp  224  is positioned with arcuate shaped pipe interface surfaces  230 ,  232 , surrounding pipe hanger  42 . Fasteners  234  are tightened, thereby securely clamping clamp  224  onto pipe hanger  42 . Surround portion  174  may then be positioned around projector  94  as before, with pipe hanger  42  in slot  192 , and top  180  above clamp  224 . Once in position, the inside surface  236  of top  180  rests on the upper surface  238  of clamp  224 . 
     One or more tamper resistant fasteners  222  may again be used to secure surround portion  174  to clamp  224 , thereby inhibiting removal of the enclosure system  172 , and coincident tampering or theft of projector  94 . In addition to providing a desirable degree of tamper and theft resistance, the enclosure system  172  also provides a measure of protection to the projector  94  against impact from objects when the projector is mounted in a setting where such impacts are a concern (i.e. basketballs in a gymnasium).