Patent Document

The present invention relates to locators in general and in particular to a method and apparatus for locating hidden utility outlets such as electrical boxes/air duct and lighting boxes after a wall covering such as gypsum board has been placed thereover. 
     CROSS-REFERANCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     REFERANCE TO SEQUENCE LISTING 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     In the field of construction it is frequently necessary to install junction boxes for electrical outlets/light switches/power points and the like. Such junction boxes are frequently located within a wall and may be attached to a wall stud or to the rear surface of the finishing panel. In such construction where the wall is to be finished with a sheeting material such as gypsum board, it is necessary to cut a hole in the gypsum board so as that the interior of the junction box may be accessed so as to install light switches/power points and the like therein thereafter the junction box may be covered with a cover plate as are commonly known. 
     Present difficulties exist in determining the location of junction boxes and the like behind a sheet of gypsum board also in determining the correct entry point for the cutting tool. These difficulties are typically presented during construction when the gypsum board is installed over the top of the junction boxes and the like. Inaccurate measuring and marking of the junction boxes can result in the holes being cut too big or in the wrong position and not corresponding to the junction box location resulting in the loss of time and money. 
     Previous attempts to solve these difficulties have located a magnet within the junction box and have detected that magnet on the exterior surface of the wall. Such attempts however have not taken into account the affects of gravity and friction on the magnets causing inaccurate marking, an example of this would be as the thickness of the drywall increases the less accurate they would become. Examples of such may be shown in U.S. Pat. Nos. 7,367,131 Horids and 4,384,396 Smolik. Previous attempts also have limitations in respect to the shape being cut relates to the template that is being used if you required numerous shapes and sizes as in various different outlets you would require numerous different templates, the present invention requires no templates once an entry point has been marked a cutting tool is entered at that point piercing through the wall covering then the junction box itself what ever the size or shape is used to guide the cutting tool. 
     Conventional methods of locating the necessary hole would be to measure the location of the junction box on the wall and then transfer the said measurement onto the gypsum board giving the corresponding hole location, another method would be to use a drywall square which again requires taking and transferring measurements and allowing for human error. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention allows the gypsum board to be fitted direct onto the wall without taking any measurements of the junction boxes and the like that are to be covered over and hidden from sight, it permits this by pushing an insert, which is the first body of the apparatus into the outlet box before a wall covering is placed there over. The said insert being specific in shape and dimension which when in place holds a magnet that may be located. The second locating body of the apparatus can then be used to find the first body, the second locating body achieves this by aligning a locating pin with a position indicator viewable through a window at the top of the said apparatus, when alignment is correct the tool may be pivoted to one side onto the scribing point and an indent made upon the front surface of the gypsum board, pin pointing an accurate entry point for a cutting tool such as a router. 
     According to the first embodiment of the present invention there is disclosed an apparatus for locating junction boxes/air duct and the like within a wall, said wall having a covering thereover. The apparatus comprises a first insertable body locatable within the junction box and the like proximate a rear surface of the wall covering, said first insertable body having a magnet located therein and a second body locatable proximate a front surface of a wall covering opposite the first body. The second body comprises a scribing point which corresponds to the entry point for a cutting tool, the apparatus further comprising an elongate member having proximate and distall ends and being pivotally mounted to the second body permitting multi axial movement. The said elongate member has a second magnet at the proximate end thereof wherein the distal end may be aligned with an alignment indicator when the scribing point is aligned for marking the entry point for a cutting tool. The distal end of the elongate member comprises a balance weight to counteract the forces of gravity upon the proximate end. 
     The elongate member may have longitudinal length extending between said proximate and distal ends, said elongate member may be pivotal about a middle portion thereof. 
     The elongate member may be pivotal about its center of mass. The elongate member may pivotally supported by a mounting carrier. The mounting carrier may be pivotally mounted to the second locating body of the apparatus. 
     Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon the review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view, 
         FIG. 1  is a perspective view of an apparatus for locating junction boxes within a wall according to the first embodiment of the invention. 
         FIG. 2  is a perspective view of the insert being installed within a junction box. 
         FIG. 3  is a cross sectional view of the apparatus of  FIG. 1  as taken along the line  3 - 3  in operation while locating a junction box. 
         FIG. 4  is a cross sectional view of the apparatus of  FIG. 1  taken along the line  4 - 4  of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1  an apparatus according to a first embodiment of the invention shown generally at  20 . The apparatus  20  comprises a first body or junction box insert body  22  and a second body or locating body  50  alignable with the first body. As illustrated in  FIG. 2  the junction box  10  may be secured to a wall stud  8 . It will also be appreciated that the said junction box may be secured to any other wall member as is commonly known in the art. The junction box  10  includes a peripheral wall  12  defining a central cavity  14 . As illustrated in  FIG. 3  a wall panel  6  may be secured over the junction box  10  and wall stud  8 . The wall panel  6  has a front surface  7  and a back surface  5 . The insert body  22  comprises a front surface  24  adapted to lay flat against a surface and peripheral edge  26  corresponding to the cavity  14  of the junction box into which it is to be fitted. The peripheral edge  26  may be defined by the top and bottom surfaces  30  and  32  respectively and first and second sides  34  and  36  respectively. The insert body  22  also includes a clip  16  adjacent side  34 . The clip  16  protrudes from front surface  24  and continues down first side  34  where the end finishes with a protruding bevel  38 . The said clip is the preferred method of securing the insert body  22  onto the peripheral wall  12  of junction box  10  within cavity  14 . It will also be appreciated that clip  16  of the said insert body  22  may be either permanently fixed or removable from the insert body  22 . 
     The insert body  22  comprises a first magnet  40  located therein for cooperation with the locating body as will be further discussed below. The first magnet  40  may be located adjacent to front surface  24  of the insert body or internally therein as illustrated in  FIG. 4 , it will also be appreciated that the insert body  22  may have any shape and outline necessary or desired so as long as the first magnet  40  is located at a constant predicable location for cooperation with the locating body  50  and to permit universal fitting into all outlets. 
     The locating body  50  comprises a body having a peripheral edge  52  as illustrated in  FIG. 1 , the locating body housing  86  being predominantly cylindrical in shape comprises scribing points  42  protruding from the said body adjacent to front surface  76 . The said scribing points are used to mark an indent into surface  7  of wall board  6  when the magnets  40  and  74  are aligned and the distal end  68  of the elongate member  66  is aligned with the alignment indicator  60 . The elongate member extends between distal and proximate ends  68  and  70  respectively and includes a balance weight  72  mounted onto the distal end of the said elongate member. The balance weight  72  provides a means of counter balancing magnet  74  inserted into proximate end  70 . When equilibrium is achieved of the elongate member the magnet  74  can operate more efficiently. The said balance weight  72  should be noted as being a crucial part of the apparatus and different from any other related prior art. 
     According to the first embodiment of the present invention the indicator  60  comprises an opening or transparent window through which an alignment arm is visible when locating body  50  has been positioned directly over the insert body within the junction box. In other embodiments it will be appreciated that the locating body may be formed of a substantially transparent body wherein the indicator  60  comprises a demarked boundary within the body such as by way of a differently coloured circle or the like. Although the indicator  60  is shown as a circle in the attached figures it will be appreciated that other shapes may be useful as well to define an area corresponding to when the locating body  50  is properly aligned with the junction box. 
     Turning now to  FIG. 3  a cross sectional view of the insert body  22  within a junction box  10  and a locating body  50  in operation for locating the junction box  10  are shown. As shown in  FIG. 3  the locating body  50  comprises a cavity  64  therein containing an elongate member  66  which is pivotally supported therein. It will be appreciated that although the cavity  64  is illustrated as being enclosed it may also be open on one or more sides to permit access to the elongate member  66 . With the elongate member being balanced it permits magnet  74  to work free from the effects of gravity and brings greater accuracy to the apparatus. Balance weight  72  may have a colour or other surface treatment to allow easy viewing through indicator  60 . 
     The elongate member  66  is pivotally mounted onto an annular shaped carrier  78  as shown in  FIG. 4  and the annular shaped carrier  78  in turn is pivotally mounted at an axis oriented perpendicular to the afore mentioned pivot points onto the said locating body housing  86  shown in  FIG. 3 . This configuration permits the elongate member  66  to pivot about both horizontal and vertical axes. It will be appreciated that cavity  64  of the locating body  50  should be large enough that there is sufficient tolerance to permit the elongate member  66  to freely rotate about a wide range of angles of both horizontal and vertical axes so as to permit the elongate member  66  to indicate that it is either above/below/left or right of first magnet  40 . 
     The locating body  50  comprises a viewing window  62  where centrally located therein is an alignment indicator  60 . The said viewing window  62  shall be transparent other than the alignment indicator  60 . The viewing window  62  shall be hemispherical in shape so as to run parallel to the swing of distal end  68  of the elongate member  66 . The above configuration will permit the user to clearly see the distal  68  at all orientations of the elongate member  66  by maintaining a constant distance between distal end  68  and the said viewing window  62 . The distal end  68  and viewing window  62  shall be equidistant throughout all angles of swing. It shall also be appreciated that the distance between distal end  68  and viewing window  62  shall be but not limited to being equidistant. 
     As illustrated in  FIG. 4  the locating body  50  has a front surface  76  adapted to engage and lay flat against a front surface  7  of wall panel  6 . In such a position the locating body may be moved along the front surface  7  until the second magnet  74  becomes attracted to the first magnet  40 . The magnetic attraction between the first and second magnet will force the elongate member  66  to orientate towards the first magnet  40 . With second magnet  74  closest to the first magnet  40  the user may then move the locating body  50  until the distal end  68  is viewable through the indicator  60 , the locating body  50  is then pivoted on one side permitting the scribing point  42  to make an indent upon surface  7  of the wall board marking an accurate entry point for a cutting tool. 
     The indicator  60  is positioned on the viewing window  62  at a position such that the proximate end  68  is viewable there through when an axis  80  of the elongate member  66  is substantially perpendicular to the front surface  7  of the wall panel  6 . In such an orientation the axis  80  of the elongate member  66  passes through the first magnet  40  and the indicator  60  so as to indicate that the indicator is substantially in alignment with the first magnet. The position of the first magnet  40  within the first insert body  22  is selected that in such an orientation the scribing points  42  of the locating body  50  corresponds to the entry point for a cutting tool. 
     In operation a user may locate the insert body  22  within with a junction box  10  to be located. Thereafter a wall panel  6  may be temporarily or permanently located there over, a user may then utilize the locating body  50  to determine the location of the junction box  10 . When the user has successfully aligned the distal end  68  of the elongate member  66  within the indicator  60  the user then may mark an entry point for a cutting tool such as a router and alike with the scribing points  42  and proceed to cut the wall panel  6 . When cutting is complete and the cut piece of the wall panel is removed the insert body  22  may then be recovered and reused. It shall be appreciated that the tools design will permit the detection of outlets manufactured out of any known type of material. 
     Optionally the elongate member  66  may be replaceable with a magnetic sensor in the locating body  50  for determining the location of the first magnet  40 . The magnetic sensor may provide an indication to a user of the distance to the first magnet  40  such that the user may move the locating body  50  until a minimum distance is indicated. Optionally a directional magnetic sensor such as but not limited to a vector magnetometer may be utilized when the sensed magnetic field of the first magnet  40  is perpendicular to the wall panel  6 . 
     The insert body  22  and the locating body  50  may be formed of any suitable material such as by the way of non-limiting example plastic/woods/alloys and metals. The magnets used for the present invention may be of any known type such as by way of non-limiting example/ferrite/neodymium/cobalt or ceramic. 
     It will be appreciated that strong magnets will be preferable for use as for the first magnet  40  and the second magnet  74  so as a to assist in accurate alignment of the elongate member  66  with the first magnet  40 . 
     While specific embodiments of the invention have been described and illustrated such embodiments should be considered illustrative of the invention only and not limiting the invention as construed in accordance with the above description.

Technology Category: 3