Patent Publication Number: US-2023163535-A1

Title: Recreational Vehicle Electrical Plug

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to U.S. provisional patent application Ser. No. 63/361,096 filed on Nov. 24, 2021, which is incorporated by reference herein. 
    
    
     BACKGROUND AND SUMMARY 
     The present disclosure relates generally to electrical connectors and more particularly to a vehicular electrical plug. 
     Conventional recreation vehicles (“RVs”), such as motor home coaches, employ an electrical cordset which includes a power wire cable with a plug at an end thereof. The plug is removably coupled to a stationary and remote, post-mounted electrical outlet. Some traditional plugs have a single light thereon that is illuminated when the plug is coupled to the outlet and power is flowing through the wire cable. These traditional devices, however, do not indicate if there is an electrical ground or polarity problem. 
     A much more complicated and expensive version is disclosed in U.S. Patent Publication No. 2021/0273447 entitled “Recreational Vehicle Power Monitoring and Reporting Device and Method” which published to Thomas on Sep. 2, 2021, and is incorporated by reference herein. This device disadvantageously has a power conditioner module, with a surge protector, that is independent from a power monitoring module. Furthermore, the power monitoring module includes memory and a microprocessor running software to calculate power load imbalances, compile databases of power offered by various RV parks, wirelessly communicate to remote user devices, receive GPS locational information, and interface with cloud memory or a host computer network. However, this complexity, extreme cost and component size are undesirable and not needed in most situations, and the many lights thereon confuse the RV user. 
     In accordance with the present invention, a vehicular electrical plug or connector is provided. In another aspect, an electrical connector includes a wire cable having a first end that is permanently connected to a wheeled recreational vehicle, a second end with an outlet-engageable plug thereon, and a switch allowing for a high potential or dielectric withstand test by the vehicle manufacturer in one switch condition, and then the switch allowing for normal use while detecting and/or alerting a user of an electrical ground and/or polarity problem in another switch condition. A further aspect of an electrical connector employs multiple lights on a plug, one of which alerts a user of an electrical ground and/or polarity problem, and another of which is illuminated when electricity is flowing through the plug. Another aspect of a vehicular electrical plug and method of manufacturing same, includes liquid polyurethane fed into a hole in a plug housing which then fills the otherwise open area therein to create a water-resistant seal for the plug. 
     The present vehicle electrical plug is advantageous over conventional devices. For example, the present plug is multifunctionally and synergistically beneficially for use in both a high potential or dielectric withstand test by the vehicle manufacturer in one switch condition, and then normal use while detecting and/or alerting a user of an electrical ground and/or polarity problem in another switch condition. The present apparatus is also advantageous by being a single assembled part with one end permanently attached to the vehicle. Moreover, the present plug is much less expensive and easier to use than traditional devices, yet which alerts a user to ground and/or polarity electrical problems. Additional advantages and features of the present apparatus and method will become apparent from the following description and appended claims, taken in conjunction with the associated drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view showing a recreational vehicle with the present electrical plug; 
         FIG.  2    is a perspective view showing the present electrical plug; 
         FIG.  3    is an exploded perspective view showing the present electrical plug; 
         FIG.  4    is a an exploded perspective view showing the present electrical plug; 
         FIG.  5    is a cross-sectional view, taken along line  5 - 5  in  FIG.  2   , showing the present electrical plug; 
         FIG.  6    is a cross-sectional view, taken along line  6 - 6  in  FIG.  2   , showing the present electrical plug; 
         FIG.  7    is an electrical circuit diagram showing the present electrical plug; 
         FIG.  8    is a perspective view showing the present electrical plug, in a first condition; 
         FIG.  9    is a front elevational view showing the present electrical plug, in a second condition; 
         FIG.  10    is a front elevational view showing the present electrical plug, in a third condition; 
         FIGS.  11 - 14    are perspective views showing a series of steps for using the present electrical plug; and 
         FIG.  15    is a cross-sectional view showing a marine vehicle version of the present electrical plug. 
     
    
    
     DETAILED DESCRIPTION 
     A preferred embodiment of a vehicular electrical connector  21  is shown in  FIG.  1   , and includes a wire cable  23  having a first end connected to a wheeled recreational vehicle  25  and an opposite second end with an electrical plug  31  thereon. Recreational vehicle  25  is preferably a motor home coach, camper van, travel trailer, fifth-wheel trailer, popup camper or the like, having wheels  33  and an internal sleeping bed. It may be self-propelled with an engine or towed. A cavity  35  is located in a side of recreational vehicle  25  and optionally contains a manually cranked or electric motor-driven winch  37  having a drum mounted upon a shelf therein, and enclosed by a pivoting door  39 . Wire cable  23  is wrapped or coiled around the drum of winch  37 , which may be extended or retracted, and the first end of the wire cable is permanently connected to an electrical circuit of the recreational vehicle; in other words, the first end it not intended to be removed therefrom without disassembling or severing it. When wire cable  23  is extended for use, plug  31  is removably connected to a remotely located and stationary NC power outlet  51  mounted on an upstanding post  53  or building. 
     Referring to  FIGS.  2 - 7   , plug  31  includes an injection molded polymeric housing  61  having an outer housing shell  61 A and an inner housing shell  61 B. Housing  61  is defined by a slightly convexly curved outside surface  63 , an opposite and generally flat inside surface  65 , a top surface  67 , a bottom surface  69 , and generally flat and parallel side surfaces  71 . Wire cable  23  extends through an aperture  73  in bottom surface  69 . Furthermore, screws  75  or rivets fasten together housing shells  61 A and B. 
     A generally U-shaped and polymeric lever  77  is manually rotatable about pivots  79 , which laterally project from side surfaces  71 . Lever  77  is movable between a nominal position  77 A aligned with side surfaces  71  and an offset angled position  77 B. This allows lever  77  to assist in pushing away and releasing plug  31  from remote outlet  31 . 
     A printed circuit board  81  and underlying flexible silicone insulator pad  83 , are fastened to upper housing shell  61 A via screws  85 . An electrical circuit  91  of printed circuit board  81  includes a disconnect switch  93 , two LED lights  95  and  97 , resistors  99  and diodes  101 . At least three and more preferably five, resistors  99 , and at least three diodes, are employed in the circuit. Conductive metal terminals or lugs are also part of circuit  91  and include a pair of electrically positive junction terminals J 2  and J 4 , an electrical ground junction terminal J 1 , and a neutral junction terminal J 3 . Positive power wires  103  and  105 , of cable  23 , are crimped, soldered or otherwise fastened onto terminals J 2  and J 4 , respectively, while grounding wire  107  is fastened to terminal J 1 . 
     The terminals all project through slots in inside surface  65  of the housing and extend generally parallel to each other and generally perpendicular to the inside surface. Wire cable  23  is secured to inner housing shell  61 B by a curved band  120  screwed to the shell. This cordset handles 50 amps and 125/250 volts of NC power, but can alternately be used for different power configurations. 
     A slidable button  121  (see  FIG.  13   ) of switch  93  is accessible through an opening  123  in outside surface  63  of plug housing  61 . Switch  93  is a double pull, double throw, on-on, surface mount 300 mA switch. It is preferred that no microprocessor be included in the plug to reduce expense. 
     Furthermore, a position indicating bezel  125  is located between a body of switch  93  and an interior of outer housing  61 A/opening  123 . A polymeric cap  127  is removably attachable to cover opening  123  via barbed snap-fit legs projecting from the body of the cap. Additionally, a pressure sensitive adhesive backed label  129  is secured within a recess in outer surface  63  of outer housing  61 A to cover and further retain cap  127 . 
     The operation of the present electrical plug apparatus  21  will now be described with reference to  FIGS.  8 - 14   . RV plug  31  shows the user the status of their 50 amp, 125/250v AC power. It shows power available by a green LED  95  and also shows reverse polarity or loss of ground conditions by a red LED  97 . The power status circuitry can be disconnected from the power wires by a switch (mechanical or magnetically controlled). During RV production testing (by the manufacturer), specifically dielectric withstand test (“HiPot”), circuitry cannot be connected to the power conductors. However, the present apparatus design allows this circuitry to be disconnected during testing and then after testing is performed, switch  93  is switched to ON which allows the power status LED to operate. 
     More specifically,  FIG.  8    shows the LED lighting condition of the plug before it is plugged into an RV park pedestal our post-mounted outlet; both LEDs  95  and  97  are not illuminated. When the plug is plugged into the RV park pedestal outlet under normal power transmission conditions, green LED  95  is ON and illuminated, as is illustrated in  FIG.  9   . Then, when a reverse polarity or loss of ground condition is detected by the plug&#39;s electrical circuit, the red LED  97  is also ON and illuminated. 
       FIGS.  11  and  13    show the initial situation where an RV manufacturer OEM receives plug  31  with cap  127  and label  129  in a bag taped to the plug. Button  121  of switch  93  is in the OFF position. Next, the manufacturer performs normal coach dielectric testing (HiPot Test) per  FIG.  12   . The HiPot high potential test checks for good isolation such that no electrical current will flow from one point to another in an over-voltage transient situation. This allows the manufacturer to determine if there are any crushed insulation, stray wire strands, corrosive contaminants around conductors, terminal spacing problems or cable tolerance issues, in the RV&#39;s internal circuits. The manufacturer test, with switch  93  open, further will include: a continuity test to ensure that all metal parts are properly bonded; an operational test to demonstrate that all equipment is properly connected and in working order; polarity checks to determine that connections have been properly made; and/or GFCI testing to demonstrate that the ground fault protection devices are installed and operating properly. It is preferred that the electrical power connector be permanently connected to the RV during this HiPot test. 
     After the testing is performed by the RV manufacturer, and with reference to  FIG.  13   , the manufacturer will manually slide button  121  of switch  93  in the direction of the illustrated arrow to the ON position (toward the LEDs) using a screwdriver tool. Next,  FIG.  14    illustrates that the manufacturer will install waterproof cap  127  into hole of housing  61  by snapping it into place. Label  129  is then affixed to housing  61  of plug  31 . There is a slight pocket or recess that guides the label in place and this label is a permanent heavy duty vinyl label. Subsequently, plug  31  is ready for normal customer use in the RV and no further operation of the switch is desired thereafter. Therefore, the present electrical circuit synergistically provides the manufacturing testing switch in addition to the multiple LED lights indicating and alerting the user of a normal power operation and detected undesired power grounding/polarity reversal problem. This multi-functionality is all performed in a single assembled part that is relatively light weight and inexpensive, and easy for the user to understand. 
     An additional optional feature includes use of a two-part, polyurethane potting compound  141  within plug  31 . Polyurethane  141  is fed or poured in a generally liquid state into an entry hole  143  in inner surface  65  of inner housing shell  61 B via a dispensing gun or valved feeding conduit. Moreover, at least one exit hole  145  is also located in the inner housing shell to allow the outflow of air. Thus, the polyurethane fills all of the air gap spaces otherwise present within housing  61  and provides a water-resistant seal for all holes, openings and apertures of housing when the polyurethane cures and solidifies, which is especially beneficial for the outdoor and all weather use of the plug. Polyurethane  141  also synergistically forms an electrical and thermal insulator while additionally providing shock absorbing resistance to electronic components therein. 
     This polyurethane feature can alternately be used for an outdoor power supply in marine applications, as is illustrated in  FIG.  15   . A plug  1031  is coupled to a wire cable  1023  longitudinally extending from a housing  1061 . The wire cable, in turn, is permanently secured to an electrical circuit of a watercraft vehicle  1024 , such as a recreational boat, or removably attachable to an outlet receptable of the watercraft vehicle. A winch having a cylindrical drum, around which the cable is coiled, can optionally be employed. 
     The marine plug  1031  includes four wires  1026  which are crimped or sonically welded to terminals  1028  which longitudinally project from a distal end of the plug opposite wire cable  1023 . At least one of the terminals has a lateral curve, and the terminals are removably connected to a remote and stationarily-mounted power supply outlet, such as on a dock or building. The wires and attached terminals are assembled into a two-part housing  1061  which has a generally circular exterior shape. A ring and sleeve  1140  are placed around the housing, and then a two-part polyurethane potting compound  1141  is fed into an entry hole  1143 . Air exit holes  1145  are also provided. Polyurethane  1141  fills the otherwise present air gap within housing  1061  to provide a waterproof seal. The polyurethane-filled housing and cable are subsequently placed into an injection mold and then overmolded with an exterior PVC polymer to create a user graspable base  1080 . Base  1080  includes a tapered proximal end surrounding a portion of cable  1023  and has a generally circular exterior shape with circumferential grooves and/or ribs thereon. 
     While various embodiments of the present electrical apparatus have been disclosed, it should be appreciated that other variations may be made. For example, alternate electrical circuits and electronic components may be used although some of the present benefits may not be realized. Furthermore, different materials and manufacturing process steps can be used, however, certain of the present benefits may not be achieved. For example, it is also envisioned that the present HiPot testing switch button may be rotated via a screwdriver-receiving slot, rather than linearly slid, between its open and closed electrical positions. As another example, the plug may or may not include the disclosed lever and polyurethane seal. Moreover, the polyurethane entry and exit holes may be in different surfaces of the housing, the housing can be differently shaped, and for use with different electrical power values, although some of the preferred advantages may not be obtained. The features of any of the embodiments may be mixed and matched in an interchangeable manner with any of the other embodiments disclosed herein, and the claims can be multiply dependent on any or all of the others. Various changes and modifications are not to be regarded as a departure from the spirit or the scope of the present invention.