Abstract:
Electrical connection boxes for use in recreational vehicle and marine applications must be adapted for a variety of electrical services and electrical connection styles. In order to standardize electrical connection boxes for these uses, a plurality of positioning tabs may be mounted within the connection box to accommodate electrical connection receptacles of various sizes. Unused positioning tabs may be removed during assembly. Further standardization can be achieved through the use of gaskets adapted for use with power cords of different sizes but having common design features to mate with a common seating surface design.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed generally to electrical devices, and more specifically to electrical connection boxes adapted for use with a variety of sizes of recepticles. 
       BACKGROUND 
       [0002]    Recreational vehicles (RVs) and boats are mobile vehicles that may periodically require connection to an outside power source. For example, many people who travel in RVs will stop overnight at a campground. The campground often provides an electrical panel with one or more electrical connection receptacles to the owner of the RV as part of the services provided for the owner&#39;s stay. The electrical panel may provide several different electrical services, ranging from 120 volt and 15 amps up to 240 volt and 50 amps. 
         [0003]    The owner of the RV may take an extension electrical cord that is connected or otherwise tied in to the RV&#39;s electrical system and plug the extension cord into the campground&#39;s electrical panel. While this appears straightforward, many problems may be encountered. For example, the RV may be designed to connect to a different electrical service than that provided by the campground. The RV owner must also be aware of the amperage draw of the electric devices in the RV and determine whether the campground&#39;s electric service is adequate. 
         [0004]    Perhaps a more compelling problem is the quality of the electric service provided by the campground. The campground&#39;s electric system may be old and in need of repair, or repairs may have been made that were insufficient or simply done wrong. Additionally, the campground&#39;s electrical system and connection points may have been subjected to abuse by previous RV owners, or may be degrading due to outside weather exposure. All of these factors may contribute to surges in the electricity supply, voltage spikes, open common or ground lines, or reversed polarity to name just a few potential problems. 
         [0005]    Boats moored at a marina face similar problems. Aging boats are notorious for having suspect electrical systems. Further compounding marine electrical problems is that the electrical system is installed over or in a water environment that is ripe with the possibility of open shorts directly to the water. A single boat with a bad electrical system has been known to cause severe damage to many nearby boats connected to the same marina electrical system. 
         [0006]    The RV and boat owner may connect one or more protective devices between the RV&#39;s or boat&#39;s electrical system and the outside electrical system to protect the vehicle&#39;s electrical system from poor quality outside electrical service. While surge protectors and voltage spike conditioners are found in several fields dealing with electric service, devices for RV and boat use must accommodate a range of connector types and electric service types, which makes fabricating these devices in a cost effective manner a challenging endeavor. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is an exploded perspective view of an electrical surge suppressor system. 
           [0008]      FIG. 2  is an exploded perspective view of an electrical surge suppressor system. 
           [0009]      FIG. 3  is an exploded perspective view of an electrical surge suppressor system. 
           [0010]      FIG. 4  is a front view of a connector box back section. 
           [0011]      FIG. 5  is a front view and top view of a gasket. 
           [0012]      FIG. 6  is a front cross-sectional view of a connector box input power cord receiver. 
           [0013]      FIG. 7  is a front view of a connector box back section. 
           [0014]      FIG. 8  is a front view and top view of a gasket. 
           [0015]      FIG. 9  is a front cross-sectional view of a connector box input power cord receiver. 
           [0016]      FIG. 10  is a front view of a connector box back section. 
           [0017]      FIG. 11  is a front view and top view of a gasket. 
           [0018]      FIG. 12  is a front cross-sectional view of a connector box input power cord receiver. 
           [0019]      FIG. 13  is a side cross-sectional view of a detail of a connector box assembly. 
           [0020]      FIG. 14  is a schematic view of a detail of a gasket. 
           [0021]      FIG. 15  is a side cross-sectional view of a connector box assembly. 
           [0022]      FIG. 16  is a side cross-sectional view of a connector box assembly. 
           [0023]      FIG. 17  is a side cross-sectional view of a connector box assembly with a cover. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    The present application is directed to electrical connection boxes. According to certain embodiments, the electrical connection box may comprise a front section and a back section forming a hollow space therebetween. The front surface may have an outer surface and a mounting hole in the outer surface, and the back section may have an inner surface. The electrical connection box may further comprise an electrical connection receptacle having a front face and a first length or a second length, the electrical connection receptacle positioned within the mounting hole. A portion of the electrical connection receptacle may extend into the hollow space forming a gap between the electrical connection receptacle and the back section inner surface. A portion of the electrical connection receptacle may extend out of the mounting hole such that the front face of the electrical connection receptacle is positioned a predetermined distance above the front section outer surface. A first set of positioning tabs may extend outward from the back section inner surface across the gap and contact the electrical connection receptacle thereby maintaining the predetermined distance when the electrical connection receptacle has a length equal to the first length. A second set of positioning tabs may extend outward from the back section inner surface across the gap and contact the electrical connection receptacle thereby maintaining the predetermined distance when the electrical connection receptacle has a length equal to the second length. 
         [0025]    Additional embodiments may comprise an electrical connection box having a power cord receiver extending outward from the connection box and forming an opening into the connection box. The opening may further comprise first and second seating surfaces. A power cord may be positioned within the power cord receiver and extend through the opening into the electrical connection box. A gasket may be disposed about the power cord and may be positioned within the opening, the gasket having first, second, and third side surfaces. The first side surface and the second side surface may be oriented relative to one another by a first angle, and the third side surface and the second side surface may be oriented relative to one another by a second angle. The electrical connection box may further comprise a locking nut having a third seating surface, the locking nut engaging the power cord receiver. The third seating surface may contact the gasket third side surface when the locking nut engages the power cord receiver, thereby urging the gasket first side surface into contact with the first seating surface and urging the gasket second side surface into contact with the second seating surface. 
         [0026]    Various embodiments may comprise an electrical surge suppressor system  100  as illustrated in  FIGS. 1 through 3 . The electrical surge suppressor system  100  may comprise an input power plug assembly  105  and a connection box assembly  125 . The input power plug assembly  105  may connect to an input power source (not shown) such as a campground or marina electrical pedestal. These pedestals may have a variety of power sources available, such as 50 amp, 30 amp and 20 amp. Proper selection of the type of input power plug assembly  105  may be required to match the available power source. For example,  FIGS. 1 and 2  illustrate input power plug assemblies  105  for 50 amp and 30 amp, respectively, input power sources. Typically, these 50 amp and 30 amp input power sources are designed as 4-wire 240 volt electrical systems (two 120 volt hot, one common, and one ground), and the input power plug assembly  105  also comprises four internal wires  120  which are in turn enclosed within a power cord jacket  115 . In contrast,  FIG. 3  illustrates an input power plug assembly for a 3-wire 120 volt electrical system (one 120 volt hot, one common, and one ground) that may have a 20 amp capacity. In addition, the input power source may have a specific type of receptacle (to receive the input power plug assembly  105 ) for each amperage service. For example, 50 and 30 amp service may be supplied using a receptacle comprising three prongs (in addition to a ground) arranged in a certain pattern. The input power plug assembly  105  may further comprise an input male plug  110  corresponding to the input power source receptacle. 
         [0027]    The connection box assembly  125  may comprise a front section  130  and a back section  135  that may be coupled together to form a generally hollow box. A gasket  140  may be disposed between the front section  130  and the back section  135  where the sections  130 ,  135  meet to seal the connection box assembly  125  from water and dirt intrusion in outdoor environments. Positioned at least partially within the hollow space formed by the front section  130  and back section  135 , there may be an outlet female receptacle  145  and one or more power monitoring devices  170 . The outlet female receptacle  145  may be coupled to the front section  130  by a mounting bracket  150 . When the outlet female receptacle  145  is coupled to the front section  130 , a front face  146  of the outlet female receptacle  145  may be positioned within a mounting hole  185  in the front section  130  such that a user may have ready access to the outlet female receptacle  145 . The front face  146  of the outlet female receptacle  145  may be positioned flush with an outer surface  131  of the front section  130 , or the front face  146  may extend slightly beyond the outer surface  131  (see  FIGS. 13 and 14  for further detail). The internal wires  120  of the input power plug assembly  105  may be coupled to the receptacle  145 . 
         [0028]    The power monitoring devices  170  may comprise electronic devices and associated circuitry (such as printed circuit boards and hard wiring) to monitor the input power source for surges, voltage fluctuations, reverse polarity, open neutral (or common), open ground, and the like. The power monitoring devices  170  may further comprise a plurality of indicator lights  175  positioned within mounting holes  180  in the front section  130 . The indicator lights  175  may inform the user of the condition of the input power supply and the operation of the electrical surge suppressor system  100  as a whole. The power monitoring devices  170  may disrupt a connection between the input power plug assembly  105  and the outlet female receptacle  145  if certain conditions are detected. These detected conditions may comprise, for example, a surge exceeding a predetermined amperage, a voltage fluctuation exceeding a predetermined amount, reversed polarity, or open circuits. The plurality of indicator lights  175  may be lit in a certain pattern or sequence (such as lighting or alternately flashing a predetermined subset of the plurality of indicator lights  175 ) to indicate various conditions to the user. For example,  FIG. 1  illustrates an embodiment comprising six indicator lights  175  which may be numbered  1  through  6  (not shown). If indicator light # 1  is lit, proper operation may be indicated. If instead, for example, lights # 1  and # 3  are lit (or, for example, alternately flashing), a surge suppressor activation may be indicated. One skilled in the art will recognize that any desired pattern of lit indicator lights  175  or number of lit indicator lights  175  may be used in a variety of embodiments without straying from the scope of this disclosure. 
         [0029]    Each of the front section  130  and the back section  135  of the connection box assembly  125  may additionally comprise a portion of power cord receiver  190 . When the front section  130  and the back section  135  are coupled together, the portions of the power cord receiver  190  may join together to form a complete power cord receiver  190 , thereby forming a power cord receiver opening  210  therebetween (see  FIGS. 4, 7, and 10 ). The input power plug assembly  105  may be positioned at least partially within the power cord receiver opening  210  such that ends of the power cord internal wires  120  are positioned within the hollow space of the connection box assembly  125  for coupling to the outlet female receptacle  145 . The input power plug assembly  105  may further pass through a locking nut  195  and gasket  197 . The locking nut  195  and gasket  197  may couple the input power plug assembly  105  to the connection box assembly  125  as described in detail below. The gasket  197  may comprise an elastomeric material to facilitate a waterproof seal. 
         [0030]    As mentioned in the discussion above in relation to  FIGS. 1 through 3 , there are a variety of different input power plug assemblies  105  that may be used in various embodiments. Custom designing front and back sections  130 ,  135  of the connection box assembly  125  with input power cord receivers  190  sized for each possible input power plug assembly would significantly increase manufacturing costs in a number of ways as compared to standardizing these components. For example, tooling would have to be created for each component which would result in substantial capital cost outlay; fewer pieces of each component would be ordered, increasing per unit costs; and a greater number of components would have to be maintained in inventory, which increases operating costs. Therefore, various embodiments include design features to allow significant standardization of components regardless of the specific input power plug assembly  105 . 
         [0031]    Referring now to  FIGS. 4 through 10 , one such design feature comprises a standardized connector box input power cord receiver  190  having an input power cord opening  210  sized to accommodate the largest input power plug assembly  105 .  FIGS. 4, 7, and 10  each illustrate a standardized (i.e., essentially identical) connector box back section  135 . The input power cord receiver  190  comprises a gasket first seating surface  205  and a gasket second seating surface  220 . The gasket first and second seating surfaces  205 ,  220  may be disposed at an angle θ1 with respect to one another (see  FIG. 13 ). This angle may be greater than 90 degrees, for example between about 110 degrees and 170 degrees.  FIGS. 4 through 6 ,  FIGS. 7 through 9 , and  FIGS. 10 through 12  each demonstrate how the same front and back sections  130 ,  135  may be used regardless of the specific input power plug assembly. 
         [0032]      FIGS. 5, 8, and 11  illustrate that each gasket  197  has an outer diameter D s  that is approximately the same as a diameter of the input power cord opening  210  as measured across the second gasket seating surface  220  such that the gasket  197  can be positioned in the input power cord opening  210 . When the gasket  197  is positioned in the input power cord opening  210 , a gasket first side surface  225  may be adjacent to the gasket first seating surface  205 , and a gasket second side surface  230  may be adjacent to the gasket second seating surface  220 . Additionally, each gasket  197  may comprise a clearance hole  198  with a diameter D 1 , D 2 , D 3  sized for an interference fit with the jacket  115  of the input power plug assembly  105 . 
         [0033]    It should be noted that in order to further standardize components of the electrical surge suppressor system  100 , the power cord receiver locking nut  195  is typically the same for all embodiments. The locking nut  195  may comprise a clearance hole  196  to accommodate passing through the input power plug assembly. A diameter of the clearance hole  196  may be essentially the same as D s . 
         [0034]    Referring now to  FIGS. 6, 9, and 12 , various embodiments of front cross-sectional views of the assembled input power cord receiver  190  are illustrated. As the locking nut  195  is screwed into place on the receiver  190 , a locking nut gasket seating surface  240  may contact a third gasket side surface  235 . As the locking nut  195  moves further downward, the gasket  197  may be urged downward until the gasket first side surface  225  makes contact with the gasket first seating surface  205 . Because the gasket  197  is now essentially restrained from further downward movement by the gasket first seating surface  205 , further downward movement of the locking nut  195  may cause the gasket  197  to expand radially due to the elastomeric properties of the gasket  197 , causing the gasket second side surface  230  to make contact with the gasket second seating surface  220 , as well as the input power cord jacket  115 . The gasket  197  may now be in contact with at least four surfaces (gasket first and second seating surfaces  205 ,  220 ; locking nut gasket seating surface  240 ; and input power cord jacket  115 ) to form an effective environmental seal preventing water and dirt from entering the connection box assembly through the input power cord opening. 
         [0035]    The locking nut gasket seating surface  240  may be disposed at an angle θ2 relative to the gasket second seating surface  220  (see  FIG. 13 ). This angle may be greater than 90 degrees, for example between about 110 degrees and 170 degrees. Similarly, each of the gasket first side surface  225  and the gasket third side surface  235  may be disposed at an angle relative to the gasket second side surface  230  (see  FIG. 14 ). Generally, the angle θ3 between the gasket first and second side surfaces  225 ,  230  may be approximately the same as the angle θ1 between the gasket first seating surface  205  and the gasket second seating surface  220 . The angle θ4 between the gasket second and third side surfaces  230 ,  235  may be approximately the same as the angle θ2 between the locking nut gasket seating surface  240  and the gasket second seating surface  220 . 
         [0036]    In  FIGS. 7 through 9  and in  FIGS. 10 through 12 , the diameter D 2 , D 3  of the input power plug assembly  105  may be substantially less than the diameter D s  of the input power cord opening  210  and the locking nut clearance hole  196 . In various embodiments, the gasket  197  may further comprise extension sleeves  215  to fill the gap between D 2  and D s  and the gap between D 3  and D s . 
         [0037]    Yet additional design features to standardize components of the electrical surge suppressor system  100  are illustrated in  FIGS. 15 and 16 . As discussed previously, a variety of different input electrical sources may be encountered. Each input electrical source may require a specific type of outlet female receptacle  145 . Each of these receptacles  145  may have different physical dimensions, particularly length. However, despite the length of the receptacle  145 , the position of the front face  146  of the receptacle  145  in relation to the connector box front section outer surface  131  (designated by H in  FIGS. 15 and 16 ) may generally remain the same. In order to maintain the relative position of the front face  146  of the receptacle  145  with the outer surface  131  of the connector box front section  130 , a plurality of positioning tabs  160 ,  165  may be coupled to a connector box back section inner surface  155 . The positioning tabs  160 ,  165  may extend outward from the inner surface  155  such that at least a portion of the tabs  160 ,  165  contact the receptacle  145 . 
         [0038]      FIGS. 15 and 16  illustrate various embodiments in which the positioning tabs  160 ,  165  comprise first level positioning tabs  160  and second level positioning tabs  165 . The second level positioning tabs  165  may extend further from the back section inner surface  155  than the first level positioning tabs. In  FIG. 15 , the length L 1  of the receptacle  145  requires the second level positioning tabs  165  to maintain the distance H between the front face  146  of the receptacle and the outer surface  131  of the connector box front section  130 . In  FIG. 16 , the length L 2  of the receptacle  145  is greater than the length L 1  of the receptacle in  FIG. 13 . Thus, in  FIG. 16 , at least a portion of the second level tabs  165  have been removed and the first level tabs  160  contact the receptacle  145 .  FIGS. 15 and 16  illustrate embodiments comprising two levels of positioning tabs  160 ,  165 . One skilled in the art will readily recognize that more or less than two levels of positioning tabs  160 ,  165  is within the scope of this disclosure. 
         [0039]    The positioning tabs  160 ,  165  in various embodiments may be flexible such that the unused positioning tabs  160 ,  165  may be removed or positioned out of the way of the receptacle  145  by breaking, tearing, cutting, melting, slicing, bending or any other method known in the art. The positioning tabs  160 ,  165  may be formed integrally with the connector box back section  135  or may be coupled to the back section  135  by adhesive of any manner, screws or other connectors, interference fit, or any other coupling method known in the art. 
         [0040]      FIG. 17  illustrates various embodiments of a receptacle cover  400  capable of being coupled to the outer surface  131  of the connector box front section  130 . The cover  400  may comprise a back section  410  in contact with the connector box front section outer surface  131 . The cover back section  410  may comprise a receiving opening  420  to receive the front face  146  of the receptacle  145 . The receptacle cover  400  may further comprise a front section  405  pivotably coupled to the back section  410  by a hinge  415 . The hinge  415  may allow the front section  405  to swing upward in the direction of the broken arrow in  FIG. 15 . 
         [0041]    The receptacle cover  400  may be fabricated of a plastic material such as polycarbonate, acrylic, polypropylene, polyethylene, and the like. The cover back section  410  may have a thickness T that is equal to or less than the height H that the front face  146  of the receptacle  145  is positioned above the outer surface  131  of the connector box front section  130 . This thickness allows the front face  146  of the receptacle  145  to be easily accessible for plugging and unplugging an electrical extension cord. 
         [0042]    The receptacle cover back section  410  may further comprise a resealable passthrough  430 . The passthrough  430  may allow an electrical cord that is plugged into the receptacle  145  to be routed out of the cover while generally allowing the cover to remain sealed. In various embodiments, the passthrough may comprise a plurality of closely spaced thin rubber strips (or other elastomeric material) that allow the cord to pass between the strips but are thin and flexible enough to generally conform around the cord and at partially reseal the opening. 
         [0043]    As used herein, the terms “having”, “containing”, “including”, “comprising”, and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. The articles “a”, “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise. 
         [0044]    The present invention may be carried out in other specific ways than those herein set forth without departing from the scope and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.