Patent Publication Number: US-11654672-B2

Title: Hand held circular heating elements

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/694,711, filed Apr. 23, 2015 and entitled “Hand Held Circular Heating Elements,” now U.S. Pat. No. 10,730,279, which is incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     This invention relates to a device that is a handheld circular heating element for use in the construction industry. More specifically, this invention relates to a handheld circular heating element used for uniformly applying heat to a two-piece membrane for separation of the outer layer of the membrane to allow for the inner layer of the membrane to be exposed. 
     2. Description of Related Art 
     Many construction projects necessitate the use of rolled waterproofing membrane that is applied to a wall to prevent moisture penetration through the wall. Certain specific types of rolled waterproofing membrane are comprised of two layers, and in certain construction applications, one of the layers must be removed from the other layer for a myriad of reasons. In these instances, it is generally necessary to pre-warm the area of the membrane for the separation of the outer layer from the inner layer. The heating of the membrane is what allows the two layers to separate, and only the areas of the membrane that are heated will separate. 
     Heat guns are used extensively in construction projects that require membranes to be separated by heat. However, the use of heat guns to provide the heat for pre-warming the membrane has several drawbacks. Heat guns only provide a small area of heat out of the nozzle. If a large area of a membrane is to be separated, then the worker has to move the heat gun around the area. This process takes a longer time than a process that heats the entire area to be removed at once, and this process of moving the heating gun produces non-uniform results, as some areas receive more heat than others. Also, if a worker desires to remove a specific area or shape from the membrane, then the heat gun has to be precisely moved around the desired area so that too much or too little of the outer layer is not heated and removed. 
     It is therefore desirable to have a device that provides uniform heat in the shape of pre-determined area to be removed in a quicker manner than with the prior used heat guns. 
     SUMMARY OF THE INVENTION 
     The present invention provides for a device that is a handheld circular heating element for use in the construction industry. Specifically the device is useful in applications where uniform heating is necessary to remove the outer layer from a two-piece waterproofing membrane. 
     The device includes a handle, an electrical supply, an on/off switch and a heating element. The handle allows the user to hold the device and is preferably insulated to prevent the heat from the heating element from burning the user. The handle also serves as the body for the device and provides a location for the mounting of the electrical supply, on/off switch and the heating element. The handle is generally circular in nature to provide a comfortable grip for the user, and preferably is tubular in shape. Mounted to the body portion of the handle is the electrical supply and the on/off switch. The electrical supply comprises an electrical box with an incoming power cord that is wired through the on/off switch, and an outgoing power cord that is wired to the heating element. The on/off switch is mounted to the electrical box and electrically located between the incoming and outgoing power cords. The heating element includes a mounting bracket, receptacle and heat-emitting burner. The mounting bracket connects to the body of the handle and extends perpendicularly therefrom. Attached to the mounting bracket is the receptacle, which is wired directly to the outgoing power cord from the electrical supply. The heat-emitting burner is plugged into the receptacle, which provides the electricity necessary to heat the heat-emitting burner. In practice, the incoming power cord is connected to a power supply, which provides electricity to the electrical supply. When the on/off switch is in the on position, electricity flows from the electrical supply through the outgoing power cord to the heating element receptacle. This electricity then powers to the heat-emitting burner which is plugged into the receptacle, thus providing uniform heat in the shape and size of the heat-emitting burner. 
     A specific application this device is useful for is the removal of specific-sized circular sections of the outer layer of a waterproofing membrane used on concrete retaining walls. In certain applications, these concrete retaining walls have protruding steel studs called “Nelson” studs, which extend out of the side of the retaining wall that is opposite the earth being retained. These Nelson studs are used as a fastening method for steel structures located on the retaining wall. After the retaining wall, including the Nelson studs, is built, a two-piece waterproofing membrane is installed on the wall to prevent water from passing from the retained earth through the wall into the structure being built. The two-piece membrane contains a PVC layer and an APC layer. The membrane is roughly cut to allow the Nelson studs to protrude through, so that the membrane can be secured directly to the concrete wall. However, if not sealed, these cuts could allow water to seep through around the Nelson studs. To prevent this moisture leak, the APC layer of the membrane must be removed, which exposes the PVC layer of the membrane. Once accessible, a PVC boot sized to fit around the Nelson stud can be chemically welded to the PVC layer to prevent moisture penetration from around the stud. If the APC layer is not heated in a precise, uniform manner, then then the membrane could become ripped which requires additional patching that is time-consuming and costly. 
     The novel features and construction of the present invention, as well as additional objects thereof, will be understood more fully from the following description when read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The improved process of the invention is further described and explained in relation to the following figures of the drawings wherein: 
         FIG.  1    is a side view of the handheld circular heating element of the present invention. 
         FIG.  2    is a perspective view of the handheld circular heating element of the present invention. 
         FIGS.  3 A- 3 D  are perspective views of the handheld circular heating element of the present invention being used by workers to remove the outer layer of a two-piece membrane on a wall. 
     
    
    
     Like reference numerals are used to describe like parts in all figures of the drawings. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIGS.  1  and  2   , a handheld circular heating element  11  used in construction projects is shown. In the preferred embodiment, the device comprises handle  10 , electrical supply  14 , on/off switch  16  and heating element  25 . Handle  10  is preferably tubular in shape and has grip portion  13  to allow gripping by the user of the device and body portion  12  to allow mounting of electrical supply  14  and heating element  25 . Handle  10  is preferably metal to allow permanent welded connection of heating element flanges  26  and mounting bracket  28  (discussed below) and to provide a more robust and stable base for the other components. It is important that handle  10  is rigid and strong to support the weight of the various components. 
     Mounted to body portion  12  of handle  10  is electrical supply  14 . Electrical supply  14  comprises electrical box  15 , which is mounted to body portion  12  of handle  10 , along with incoming power cord  18  and outgoing power cord  20 . Preferably, incoming power cord  18  and outgoing power cord  20  enter and exit electrical box  15  through holes in the side of electrical box  15  and are secured in place through wire clamps. On/off switch  16  is mounted in electrical box  15  and electrically connected between incoming power cord  18  and outgoing power cord  20 . On/off switch  16  controls the flow of electricity from incoming power cord  18  to outgoing power cord  20 . 
     Heating element  25  comprises receptacle  22  and heat-emitting burner  24 . Receptacle  22  is electrically connected to outgoing power cord  20 , which provides electricity to receptacle  22  when on/off switch  16  is switched to the on position. Heat emitting burner  24  plugs into receptacle  22 , and when receptacle  22  is receiving electricity, heat-emitting burner  24  becomes hot. Receptacle  22  is connected to body portion  12  of handle  10  through the use of mounting bracket  28 . Mounting bracket  28  is attached to body portion  12  of handle  10  and extends perpendicularly therefrom. The length of mounting bracket  28  is such that it is long enough to provide a secure mounting location for receptacle  22  at the precise location needed for heat-emitting burnerm  24  to plug-in to receptacle  22  and be mounted concentrically with body portion  12  of handle  10 . Heat-emitting burner  24  is mounted to body portion  12  of handle  10  through the use of flanges  26 . Flanges  26  are preferably triangular in shape and are welded to both heat-emitting burner  24  and body portion  12  of handle  10 . This welding provides a rigid connection of heat-emitting burner  24  to handle  10  and allows for precise control of placement of heat-emitting burner  24 . Heat-emitting burner  24  is preferably circular in nature and is formed as a concentric spiral shape where the diameter of each ring of heat-emitting burner decreases uniformly as it nears the center. Hole  30  is located in the center of heat-emitting burner  24 , which is aligned with the open center of tubular body portion  12  of handle  10 . This allows handheld circular heating element  11  to be placed over Nelson stud  32  during operation of the device (discussed below in reference to  FIG.  3   ). 
     Referring to  FIGS.  3 A- 3 D , handheld circular heating element  11  is shown in use in an exemplary application. This application shown is for use on a concrete retaining wall that has Nelson studs  32  protruding therefrom, which are used as anchors for a fastening method of attaching steel structures to the wall. Waterproof membrane  35  has been placed on the wall and holes have been cut (not shown) in waterproof membrane  35  for Nelson studs  32  to protrude through such that membrane  35  can be affixed directly to the wall. Holes cut in membrane  35  must be sealed to prevent moisture from passing through the wall and into the interior space. In this application, membrane  35  is a two-piece membrane with an underlying PVC layer and an overlying APC layer. One method for sealing the holes in membrane  35  is to remove the overlying APC layer and chemically weld PVC sealing boots to the underlying PVC layer of membrane  35 . 
     To accomplish this removal of the overlying APC layer, handheld circular heating element  11  is used. First, the operator switches on/off switch  16  to the on position, which provides electricity to receptacle  22 . Heat-emitting burner  25  begins warming uniformly due to its concentric spiral shape. When heat-emitting burner  25  has reached the desired temperature, the operator places handheld circular heating element  11  into position by sliding the device over Nelson stud  32 , which fits into hole  30  of heat-emitting burner  25  and then into tubular body  12  of handle  10 . This placement allows heat-emitting burner to be placed directly adjacent to membrane  35 . When the overlying APC layer has been heated sufficiently, typically within 20-30 seconds, the operator removes handheld circular heating element  11  from Nelson stud  32  and switches the device off. Because of the design, he can hang the device on an adjacent Nelson stud  32  while he works to remove the circular section of the overlying APC layer that was warmed, which leaves hole  36  in the overlying APC layer. This removal allows access to the underlying PVC layer, such that a PVC boot can be chemically welded in place to seal the hole in membrane  35  around the Nelson stud  32  protrusion. For the exemplary application, a round heat-emitting burner is desired due to the circular shape of the PVC boot. However, it should be understood that heat-emitting burner  25  could take any shape if a certain application necessitates certain shapes to be removed. Such shapes could include diamond, triangular or rectangular. 
     Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading the present disclosure, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.