Patent Publication Number: US-6713696-B1

Title: One piece toggle switch cover with integral panel standoff and seal receptacle

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to a one piece toggle switch cover having an integral panel standoff and seal receptacle. 
     BACKGROUND OF THE INVENTION 
     A typical toggle switch has a toggle lever that is pivoted about a pin in order to control the position of one or more switch contacts. The pin passes through a bushing and the toggle lever so as to support the toggle lever for pivotal movement. Toggle switches are used in a variety of applications that frequently require the mounting of the toggle switches to panels such that the toggle levers of the toggle switches protrude from a first side of the panels and extend through the panels to operate switches on an opposing second side of the panels. A seal is usually provided between the toggle lever and the switch in order to prevent moisture and other contaminants from passing around the toggle lever and into the switch. 
     The current method of mounting a toggle switch to a panel relies on the use of a threaded bushing of the toggle switch. A first nut is threaded onto the threaded bushing to a predetermined depth. The first nut is used as a panel stop. That is, the toggle switch is inserted through a corresponding hole through the panel until the first nut engages the second side of the panel, at which point the first nut prevents further movement of the toggle switch through the hole. At this point, the toggle switch stands off of the panel by the predetermined depth established by the first nut. A second nut is then threaded onto the bushing and tightened until it engages the first side of the panel. Accordingly, the second nut secures the toggle switch to the panel. 
     This mounting arrangement has a number of problems. For example, the use of two nuts, one for the stand off depth and one for securing the toggle switch to the panel, is labor intensive. Also, the use of these two nuts results in inconsistent stand off depths between toggle switches when multiple toggle switches are mounted to the same panel because the same stand off depth from toggle switch to toggle switch is difficult to maintain. Further, it is difficult and expensive to seal the panel around the toggle switch because of the presence of a key slot and threads typically used in the cover bushing. A specially manufactured sealing nut is usually required to provide this sealing and, optionally, a specially manufactured sealing washer is provided to seal the keyway. 
     The present invention is directed to a toggle switch that overcomes one or more of these or other problems. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention, a toggle switch comprises a one piece integral switch cover, an O-ring seal, and a toggle lever. The one piece integral switch cover has a plate, a stand off, and a bushing. The seal seats around the bushing. The toggle lever extends through an opening of the bushing. 
     In accordance with another aspect of the present invention, a toggle switch comprises a panel, a one piece integral switch cover, an O-ring seal, and a toggle lever. The panel has a hole therethrough and has first and second opposing sides. The one piece integral switch cover has a plate, a stand off, and a bushing. The stand off has protrusions extending therefrom, the stand off engages the panel, and the stand off determines a stand off depth of the plate from the panel. The bushing extends through the hole so that the bushing is on the first side of the panel and the plate and stand off are on the second side of the panel. The seal is seated around the bushing, and the seal is squeezed between the panel and the stand off. The toggle lever extends through an opening of the bushing. 
     In accordance with still another aspect of the present invention, a method is provided to fasten a toggle switch to a panel. The toggle switch comprises a plate, a stand off, a seal, a bushing, and a toggle lever. The stand off has protrusions extending therefrom, and the stand off and the protrusions determine a stand off depth of the plate from the panel. The seal is seated around the bushing and within the protrusions so that the protrusions determine an amount of compression of the seal. The toggle lever extends through an opening of the bushing. The method comprises the following: inserting the bushing and the toggle level through a hole in the panel until the protrusions engage the panel; and, fastening the toggle switch to the panel by use of a single fastener so that the seal is squeezed between the stand off and the panel to provide a seal between the panel and the toggle switch. 
     In accordance with yet another aspect of the present invention, a toggle switch comprises a switch cover and a toggle lever. The switch cover has a plate and a bushing, and the bushing has a threaded area in proximity to the plate and an unthreaded area away from the plate. The toggle lever extends through an opening of the bushing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages will become more apparent from a detailed consideration of the invention when taken in conjunction with the drawings in which: 
     FIG. 1 is an isometric view of a toggle switch according to one embodiment of the present invention; 
     FIG. 2 is a top view of the toggle switch shown in FIG. 1; 
     FIG. 3 is a side view of the toggle switch of FIG. 1; 
     FIG. 4 illustrates the toggle switch of FIGS. 1-3 mounted to a panel; and, 
     FIGS. 5-7 illustrate an easy start thread feature according to an embodiment of the invention. 
    
    
     DETAILED DESCRIPTION 
     A toggle switch  10  according to one embodiment of the present invention is shown in FIGS. 1-3. The toggle switch  10  includes a toggle lever  12  and a switch cover  14  that are joined together by a pin  16  suitably pressed in or otherwise fastened to the switch cover  14 . 
     The switch cover  14  of the toggle switch  10  is a one piece integral switch cover having a plate  18 , a stand off  20 , and a bushing  22 . Because the switch cover  14  is a one piece integral switch cover, the material forming the switch cover  14  is continuous having no breaks as would be expected if the switch cover  14  were made up of separate parts fastened or bonded together. Accordingly, the material of the switch cover  14  continuously forms the plate  18 , the stand off  20 , and the bushing  22 . For example, the switch cover  14  may be extruded or cast. 
     The plate  18  has holes  24  for receiving rivets, screws, or other fasteners to fasten the switch cover  14  to a switch case  26  (FIG. 4) that contains at least one movable switch contact operated by the toggle lever  12 . A seal  28  is provided between the toggle lever  12  and the bushing  22  of the switch cover  14  in order to prevent moisture and other contaminants from passing through the toggle switch  10  between the toggle lever  12  and the bushing  22 . 
     The stand off  20  has protrusions  30  that have a dimension perpendicular to the plate  18  for determining the stand off depth, i.e., the distance that the plate  18  and the switch case  26  fastened thereto stand off from the panel to which the toggle switch  10  is fastened. The protrusions  30  are also continuously formed from the material that is used to form the switch cover  14 . 
     The protrusions  30  form a receptacle for holding an O-ring seal  32 . The stand off  20  and the protrusions  30  form a seal receptacle that receives and helps to position the O-ring seal  32  when the switch mounting nut (discussed below) is tightened to the point where the protrusions  30  bottom out against the bottom of the panel. The protrusions  30  also prevent the O-ring seal  32  from being overly squeezed as a switch mounting nut  34  is tightened. Moreover, the protrusions  30  further result in a higher force being transmitted to the panel so as to prevent the toggle switch  10  from spinning. 
     The bushing  22  and the toggle lever  12  have corresponding pin receiving holes to receive the pin  16 . The pin  16  accordingly provides a pivot about which the toggle lever  12  is toggled. The bushing  22  is also provided with threads to receive the switch mounting nut  34  so as to fasten the toggle switch  10  to a panel  36 . 
     During mounting of the toggle switch  10  to the panel  36  as shown in FIG. 4, the toggle switch  10  is inserted through a hole in the panel  36 , and the switch mounting nut  34  is threaded onto the bushing  22  and tightened until the protrusions  30  bottom out on the panel  36 . The O-ring seal  32  is accordingly squeezed between the panel  36  and the stand off  20  in order to thereby provide a tight seal between the panel  36  and the toggle switch  10 . 
     As compared to prior art panel mounted toggle switches, the toggle switch  10  allows for faster and more consistent switch installation. The protrusions  30  and the stand off  20  with the O-ring seal  32  provide a flat sealing surface as well as a panel stop. Accordingly, only a single nut, i.e., the switch mounting nut  34 , is required to fasten the toggle switch  10  to the panel  36  at the proper depth. In addition, a locking washer on the same side of the panel as the switch mounting nut  34  may be provided to prevent the switch mounting nut  34  from loosening under vibration or other conditions. In this case, the switch mounting nut  34  and the locking washer are considered to be a single fastener. 
     As shown in FIGS. 5-7, the bushing  22  is threaded except at an unthreaded area  40  that is uppermost on the bushing  22 . The unthreaded area  40  of the bushing  22  has a maximum outside diameter that is less than the corresponding minimum minor diameter of the threads on the switch mounting nut  34 . Accordingly, the unthreaded area  40  of the bushing  22  allows the switch mounting nut  34  to be easily positioned on the bushing  22  in a plane located perpendicularly to the axis of bushing  22  prior to actually threading the switch mounting nut  34  onto the bushing  22 . The unthreaded area  40  provides easy alignment of the switch mounting nut  34 , and significantly reduces the possibility for cross threading of the switch mounting nut  34  onto the bushing  22 . Once the switch mounting nut  34  is positioned in this location as dictated by the unthreaded area  40 , simply rotating the switch mounting nut  34  will successfully engage the threads of the switch mounting nut  34  with the corresponding mating threads of the bushing  22 . This feature not only contributes to easier hand mounting of the toggle switch  10 , but also is especially beneficial when using power equipment to fasten the switch mounting nut  34  to the bushing  22  because improper alignment that might otherwise result can rapidly cause cross threading, thus rendering the toggle switch  10  useless. The length of the unthreaded area  40  along the bushing  22  may be selected based upon the height of the switch mounting nut  34  but should be sufficient to permit this easy threading feature. 
     Modifications and/or alternatives of the present invention will occur to those practicing in the art of the present invention. For example, as described above, the toggle switch  10  is fastened to the panel  36  by way of the switch mounting nut  34 . However, other fastening devices, such as c-springs, can be used to fasten the toggle switch  10  to the panel  36 . 
     Accordingly, the description of the present invention is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details may be varied substantially without departing from the spirit of the invention, and the exclusive use of all modifications which are within the scope of the appended claims is reserved.