Patent Publication Number: US-6215108-B1

Title: Multiple electric element mounting system

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to electrical resistance heaters and assemblies and more particularly relates to a mounting system used to mount electrical heating elements. 
     Electric resistance heating assemblies of the type having a resistance element connected to a source of electrical power and mounted on a suitable support structure are used in various applications. For example, such assemblies may be used to independently provide heat for a space or room. Alternatively, such assemblies may be incorporated into a larger piece of equipment, such as an air conditioning unit, to provide warm air when required. 
     Electric resistance heating assemblies are well known in the art. For instance, U.S. Pat. No. 4,528,441, which is owned by a common assignee of the present invention and which is incorporated in its entirety herein by reference, describes electrical insulators used in electrical resistance heating assemblies. Further, U.S. Pat. No. 4,827,602, which is owned by a common assignee and which is incorporated in its entirety herein by reference, describes an electric heater assembly fixture and a method of use for the same. In addition, U.S. Pat. No. 3,952,409, which is also owned by the common assignee and which is incorporated in its entirety herein by reference, describes a method of manufacturing a support structure for an electric heating assembly that includes a plurality of heating elements. 
     Systems that are used to support the heating coil elements of the electrical resistance heating assemblies are also well know in the art. Typically, the systems that are utilized to support the electric resistance heating assemblies comprise a metal rack that includes a series of support rods or bars. In order to support the heating elements, the frame of the heating element is placed in contact with the support bar and a plurality of rivets are used to fix each individual heating element to the support structure. 
     The systems and brackets heretofore known for supporting electric resistance heating assemblies, while structurally sound and efficient, nevertheless are difficult and time-consuming to manufacture. The difficulty and time-consumption translate to a labor-intensive manufacturing process. Of course, the labor intensive nature of the manufacturing process translates to high costs of manufacture. 
     In addition, the traditional methods of supporting electric resistance heating assemblies present difficulties in those instances when repair of the assemblies is necessary. Most notably, the metal racks of the prior art comprise a plurality of support bars riveted to a plurality of heating coil elements. In the event that repair can be accomplished by the replacement of a single heating coil, the prior art methods require the removal of the rivets from one section of the metal rack, thereby making the repair process long and difficult. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide an improved mounting system for supporting an electric resistance heating assembly. 
     It is another object of the present invention to provide an improved mounting system for supporting an electric resistance heating assembly that is easy and relatively low in cost to manufacture. 
     It is yet another object of the present invention to provide an improved mounting system for supporting an electric resistance heating assembly that provides an easier method of repairing electric resistance heating assemblies. 
     These and other objects are attained by providing an electric element mounting system including a housing and at least one heating element. Each element includes a frame having a longitudinal axis and a distal end, a heating coil and a wire terminal for electrically and mechanically coupling the element to the front panel. A substantially planar mounting bracket is located within the housing, the bracket including at least one aperture. The bracket is located within the housing and placed in a plane perpendicular to the longitudinal axis of said frame so that the distal end is placed through the aperture to mount the element upon the bracket. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partially exploded plan view of an electric resistance heating assembly using a prior art method of supporting the heating coil elements. 
     FIG. 2 is a plan view of an electric resistance heating assembly that utilizes a mounting bracket system that embodies the present invention. 
     FIG. 3 is a side elevation view of a electric resistance heating element and bracket therefore that embodies the present invention. 
     FIG. 3 a  is a side elevation view of a portion of the mounting bracket of the present invention. 
     FIG. 4 a  is a front elevation view of a mounting bracket that embodies the present invention. 
     FIG. 4 b  is a cross-sectional view along line  4   b — 4   b  of FIG.  4 . 
     FIG. 6 is a side elevation view of an electric resistance heating assembly that utilizes a mounting bracket system that embodies the present invention. 
     FIG. 7 is a rear elevation view of a mounting bracket that embodies the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown a prior art method of mounting an electric resistance heating assembly  10  within a housing  12 . There are a plurality of heating coil elements  14  that are coupled to a heating assembly front panel  16 . The heating coil elements  14 , as is well known in the art, include a metal frame with a resistance coil mounted thereon and a wire terminal  18  with a corresponding insulator  20 . The wire terminal  18  and insulator  20  are used in conjunction with other well known fastening methods to electrically and mechanically couple the heating elements  14  to the panel  16 . The panel  16  includes fuses  22  and other required electronics to supply the necessary electrical currents to the individual heating coil elements  14 , as is well known in the art. The heating coil elements  14  are attached at their distal end to a support structure  24 . The support structure  24  comprises a number of metal bars that are coupled to each other. The support structure  24  is coupled to each respective heating coil element  14  by riveting the distal end of the element  14  to one of the metal bars of the support structure  24 . In this way, the support structure  24  is attached to each of the elements  14  and forms an interconnected framework of metal bars. The entire heating assembly  10  is coupled by well known methods to the housing  12 , such as a sheet metal screw  26 . 
     Turning now to FIG. 2, there is shown an electric resistance heating assembly  30  within a housing  32  that is mounted utilizing the mounting system of the present invention. The heating assembly  30  includes a plurality of heating coil elements  34 . The heating coil elements  34  are electrically and mechanically coupled to a heating assembly front panel  36 , as will be explained in more detail below. The panel  36  includes fuses  42  and other required electronics to supply the necessary electrical currents to the individual heating coil elements  34 . The heating coil elements  34  are coupled to a mounting bracket  44  that is located within the housing  32 , as will be explained in more detail below. 
     Referring to FIG. 3, there is depicted a heating coil element assembly that includes a frame  35  having a longitudinal axis. The heating coil element  3  further includes a heating coil  33  which is supported by frame insulators  37 , a wire terminal  38 , and an insulator  40 . At the proximal end of the frame  35 , there is located a sheet metal screw  39  that is used to fasten the heating coil element to the panel  36 . One skilled in the art would recognize that there are many suitable fasteners, wire terminals, and insulators that would suffice to electrically and mechanically couple the heating coil element  34  to the panel  36 . At the distal end of the frame  35 , there is located a tab  45  that is used to secure the heating coil element to the mounting bracket  44 , as will be explained in greater detail below. As is depicted in FIG. 3, the tab  45  is preferably rectangularly shaped at the most distal point with a narrower portion immediately adjacent to the frame  35 . 
     Referring now to FIG. 4, there is shown the mounting bracket  44  of the present invention. The bracket  44  is substantially planar and is constructed of a strong and durable material, preferably sheet metal. The bracket  44  includes a plurality of apertures  50 . The number of apertures  50  coincides with the number of heating coil elements. Typically, there are three, four or six apertures on the bracket  44 . The apertures  50  are spaced about the planar surface of the bracket  44  to allow placement of the distal end of the heating coil elements into the apertures  50  so that the heating coil elements have sufficient space relative to each other. In the preferred embodiment, the apertures  50  are diamond-shaped, with one axis longer than other axis. The longer axis is sized to accept the rectangular portion of the tab  45  of the heating coil element  34 . In addition, in the preferred embodiment, the aperture  50  is recessed into the front planar surface  51 , as is depicted in FIG. 4 b.    
     Referring now to FIG. 6, the heating coil elements are shown with the tab  45  inserted into the bracket  44 . The bracket  44  is situated with the front planar surface  51  located in a plane that is perpendicular to the longitudinal axis of the heating coil elements. The proximal end of the frame  35  including the wire terminal  38  is electrically and mechanically coupled to the panel  36 . The insulator  40  is placed in contact with the wire terminal  38  and the proximal end of the frame  35  is mechanically coupled to the panel  36  using a sheet metal screw  39 , as described above. 
     During installation, the tab  45  is passed through the aperture  50  with the rectangular portion of the tab  45  passing through the longer axis of the diamond-shaped aperture  50 . When the entire rectangular portion of the tab  45  has passed through the aperture, the heating coil element is rotated so that the rectangular portion of the tab  45  rotates into a position that does not allow removal of the heating coil element from the bracket  44  because the tab  45  cannot pass through the smaller axis of the diamond-shaped aperture  50 . In the preferred embodiment, the heating coil element must be rotated at least 15 degrees and preferably is rotated 90 degrees. Referring to FIG. 7, the rear side  52  of the bracket  44  is shown with the tabs  45  of the heating coil elements  34  in place. As depicted in FIGS. 3 a  and  7 , the heating coil elements have been rotated 90 degrees. 
     The mounting bracket of the present invention is significantly easier to manufacture than prior art devices. It is a single piece and is preferably manufactured from sheet metal. Contrary to prior art devices, there is no need to use rivets to fasten the heating coil elements to the bracket and therefore the manufacture of the mounting structure and the entire heating assembly is much easier. In addition, a repair of a single element in a two-element heater only requires the removal of the screw from the front panel and a counter rotation of the element to remove it from the mounting bracket. There is no need to disassemble the entire support structure to replace only one element. Large heaters with multiple elements may require loosening some screws to remove an element. 
     Of course, the foregoing description is directed to particular embodiments of the present invention and various modifications and other embodiments of the present invention will be readily apparent to one skilled in the art to which the present invention pertains. Therefore, while the present invention has been described in conjunction with these particular embodiments, it is to be understood that various modifications and other embodiments of the present invention may be made without departing from the scope of the invention described herein and as claimed in the appended claims.