Abstract:
A photovoltaic panel system is reconfigurable. In another aspect, multiple photovoltaic modules are removably attachable in a linear manner via interfacing male and female electrical connectors and/or magnetic electrical connectors. A further aspect of the present system provides additive collective voltage increases by plugging in multiple photovoltaic modules along one axis while also providing additive collective current increases by connecting these and/or other photovoltaic modules along a generally perpendicular axis.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application Ser. No. 61/706,831, filed on Sep. 28, 2012, which is incorporated by reference herein. 
     
    
     BACKGROUND AND SUMMARY 
       [0002]    The present invention relates generally to photovoltaic panels and more particularly to a reconfigurable photovoltaic panel and electrical connector system. 
         [0003]    Various portable and modular solar panel configurations are known. For example, reference should be made to U.S. Patent Publication No. 2012/0235477 entitled “Modular Portable Energy System” to Korman; U.S. Patent Publication No. 2011/0290307 entitled “Modular Solar Panel System” to Workman et al.; and U.S. Pat. No. 6,476,311 entitled “Portable Multiple Power Supply Comprising Solar Cell” to Lee et al. The preceding patents and patent publications are all incorporated by reference herein. These traditional constructions are disadvantageous by requiring complex connections between panels and/or requiring outer retention cases, which thereby increases cost, potential failure modes, and extra assembly steps. Furthermore, when one of these conventional solar panel cells is damaged, the entire system must typically be replaced which is especially disadvantageous when used in a portable manner which is more prone toward abuse. 
         [0004]    In accordance with the present invention, a photovoltaic panel system is reconfigurable. In another aspect, multiple photovoltaic modules are removably attachable in a linear manner via interfacing male and female electrical connectors and/or magnetic electrical connectors. A further aspect of the present system provides additive collective voltage increases by plugging in multiple photovoltaic modules along one axis while also providing additive collective current increases by connecting these and/or other photovoltaic modules along a generally perpendicular axis. In yet another aspect, a foam-backed glass photovoltaic cell is employed with outwardly projecting electrical connectors. Another aspect of the present system uses a flexible photovoltaic cell with attached electrical connectors. 
         [0005]    The present photovoltaic system is advantageous over traditional constructions. For example, the reconfigurability and interchangeability of the photovoltaic modules allow for easy and quick replacement of only a failed or broken module with another in a very fast (for example, less than 10 seconds for disassembly and assembly) and tool-free manner. It is also advantageous that the specific electrical connectors disclosed removably secure adjacent modules together along any edge of the photovoltaic modules while also providing the electrical interface therebetween in a multifunctional manner. Furthermore, the solar modules can be snapped together in an infinite stacked quantity to increase electrical generation depending upon the specific power requirements of an attached portable electrical device. The present system is ideally suited for lightweight and removable fastening to a flexible bag such as a backpack, the roof of an automotive vehicle, the roof of a building structure, or a water craft such as a recreational boat. Additional advantageous and features of the present invention will be ascertained from the figures, description and appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view showing the present photovoltaic panel system attached to a backpack; 
           [0007]      FIG. 2  is a perspective view showing the photovoltaic panel system attached to an automotive vehicle; 
           [0008]      FIG. 3  is a perspective view showing the photovoltaic panel system attached to a building structure; 
           [0009]      FIG. 4  is a perspective view showing a photovoltaic module employed in the photovoltaic panel system; 
           [0010]      FIGS. 5A and 5B  are perspective views showing electrical connectors employed in the photovoltaic panel system; 
           [0011]      FIG. 6  is a cross-sectional view, taking along line  6 - 6  of  FIG. 4 , showing the photovoltaic module; 
           [0012]      FIG. 7  is a perspective view showing a set of the photovoltaic modules exploded apart along a first axis; 
           [0013]      FIG. 8  is a perspective view showing a set of the photovoltaic modules exploded apart along a second and generally perpendicular axis; 
           [0014]      FIG. 9  is a perspective view showing an array of exploded apart photovoltaic modules; 
           [0015]      FIG. 10  is an electrical diagram showing three photovoltaic modules; and 
           [0016]      FIG. 11  is a perspective view showing a pair of photovoltaic modules employing an alternate embodiment type of electrical connectors. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Referring to  FIGS. 1 ,  4  and  5 , a preferred embodiment of a reconfigurable photovoltaic panel system  21  includes multiple photovoltaic or solar modules  23  which are connected to a portable electronic device  25  through a flexible wire  27 . Each photovoltaic module  23  includes a photovoltaic cell  31  having a peripheral edge  33  thereof, at least a majority of which is encapsulated or surrounded by a polymeric casing or frame  35 . In one construction, photovoltaic cell  31  includes a flexible polymeric sheet made from polyethylene, EPDM, ABS, or the like. In another configuration, as shown in  FIG. 5 , photovoltaic cell  31  is a thin and rigid sheet of glass backed by an open cell but stiff foam  37 , which is at least  10  times as thick as the adjacent photovoltaic cell  31 , which is approximately 1/16 th  of an inch thick. Each photovoltaic module  23  is preferably no larger than three inches by six inches by one-half inch to allow for a portable array. Casing  35  is preferably an epoxy material. Foam  37  and casing  35  serve to reinforce, protect and deter breakage of glass photovoltaic cell  31 . 
         [0018]    Furthermore, a set of fasteners  39 , such as hook-and-loop fasteners, snapped together clasps, hooks, adhesive or other attachments, serve to removably attach a back side of casing  35  to a flexible fabric, leather or vinyl carrying bag, such as a backpack  41 . In the present example, electronic component  25  is a hand-held communications device, such as a cellular telephone, computer, audio visual device or the like, which is temporarily carried within a pocket of the backpack  41 . Photovoltaic cell  31  can be made in accordance with U.S. Pat. No. 7,342,171 entitled “Integrated Photovoltaic Roofing Component and Panel” which is issued to Kahouri et al. on Mar. 11, 2008 and U.S. Pat. No. 6,307,145 entitled “Solar Cell Module” which issued to Kataoka et al. on Oct. 23, 2001, both of which are incorporated by reference herein. 
         [0019]      FIG. 2  illustrates an array of the reconfigurable photovoltaic panels  21  removably attached to a roof or other exterior surface of an automotive vehicle  51 . A flexible wire  53  supplies electricity generated by the photovoltaic panels  21  to an internal electronic device, such as a global positioning system display  55 , communications device, audio visual device or the like. Moreover, a structural building  57  is illustrated in  FIG. 3  upon which is attached an array of reconfigurable photovoltaic panels  21 . The panels are connected to electronic devices  59 , such as a television, computer or the like within the building structure. The reconfigurable photovoltaic panels  21  can be removably attached to the roof or other exterior wall of the building structure by way of roof clamps, screw-in brackets or the like. 
         [0020]    Returning to  FIGS. 4-6 , one or more electrical connectors outwardly protrudes from each peripheral edge  71  of each photovoltaic module  23 . In the exemplary module shown, a pair of male electrical connectors  72  extend from a top edge, a pair of female electrical connectors  81  extend from an opposite bottom edge, a pair of male electrical connectors  72  extend from one side edge while a pair of female electrical connectors  81  extend from the opposite side edge. The male electrical connectors preferably have a slightly tapered, frusto-conical distal section  73  which is matable with a female connector, and a rounded or pointed distal end  75 . Mating section  73  has a generally circular cross-sectional shape. A barb or knob  77  laterally protrudes from a side of mating section  73  and a proximal flat section  79  is affixed to a back side of photovoltaic cell  31  by soldering or other permanent method. 
         [0021]    Female electrical connector  81  includes a substantially circular-cylindrical, mating barrel section  83  with an open end  85  operable to receive tapered mating section  73  of male connector  72  therein. A generally flat proximal section  87  is connected to the back side of photovoltaic cell  31  by soldering or the like. Barb  77  slightly spreads apart barrel section  83 , which is stamped and bent metal, during entry and then barb  77  snaps into an open intermediate section  89  of female connector  81 ; this supplies a snap-in connector-to-connector retention force greater than the extraction force. 
         [0022]    The proximal end of each electrical connector is located between the glass photovoltaic cell  31  and adjacent foam  37  when the rigid glass construction is employed. The mating portions  73  and  83  of the male and female electrical connectors, respectively, protrude through openings in the encapsulating casing  35 . Both electrical connectors  72  and  81  have a length at least twice as large as width. Optionally, a polymeric socket  91  can be secured around an outside of either or both female and male electrical connectors to supply an extra or alternative snap-fit engagement with an opposite mating polymeric socket, with a barb and flexible arm snap-fit type arrangement engaging into a slot or lateral surface. 
         [0023]    It is noteworthy that the male electrical connectors  72  from one photovoltaic module  23  are insertable into the female electrical connectors  81  of an adjacent photovoltaic module  23  in a generally linear and tool-free manner. These electrical connectors (with or without the optional socket) also have a multi-functional role by serving as the sole structure for removably securing together the adjacent photovoltaic modules while also carrying electricity between adjacent modules. The simplicity of this design allows for easy and quick detachment and then reattachment in a reconfigurable manner in less than 10 seconds without requiring the use of any threaded fasteners, welding, soldering or any tools. 
         [0024]    Any quantity of photovoltaic modules  23  can be attached together in the manner previously described. Various array configurations are shown in  FIGS. 7-9 . When the modules are arranged along one axis, such as that shown in  FIG. 7 , the voltage is additively increased with each module contributing to the total system voltage. Conversely, when each module is attached along an offset and perpendicular axis, such as that as illustrated in  FIG. 8 , each module adds to the total system current. Moreover, when the modules are attached along both axes, such as that portrayed in  FIG. 9 , both voltage and current are increased by each additional module attached to provide the power generation needs of the specific electronic device(s) to be powered. For example, for the cellular telephone version of  FIG. 1 , five photovoltaic modules can be vertically stacked together to provide five DC volts or six panels can be interconnected to provide six volts, while only two to five modules may be needed along the offset axis to provide between 200-500 milliamps and more preferably 330 milliamps for the cellular telephone use. Meanwhile, if a laptop computer is to be operated based on the photovoltaic panel system, then the user can simply connect on additional photovoltaic modules along both axes with the same connecting wire  27  being connected to a single pair of electrical connectors (the same that would otherwise interconnect with an adjacent module), or through an adaptor which may connect to multiple pairs of the module electrical connectors. A voltage limiter, diodes and other electronics may additionally be employed in an adapter. The electrical schematic arrangement between the reconfigurable photovoltaic modules is shown best in  FIG. 10 . 
         [0025]      FIG. 4  illustrates a status indicator option wherein an LED indicator light  111  and an interface button or switch  113  are mounted to casing  35 . When a user wants to ascertain the charging status and capability of the specific module  23  then he or she pushes button  113  which completes a diagnostic circuit for illuminating light  111  if the desired condition is present. The illumination may alternately be a display on glass photovoltaic cell  31  or a graduated and elongated bar which shows full or partial power generating capability and health. If the user finds that one of the modules  23  in the system array  21  is faulty (the light does not illuminate) then that module can easily be removed and replaced by any of the other identically configured modules in its place. This serves to provide a low cost and robust power generation system with reconfigurable “plug and play” type interconnections for use in a portable environment where a trained electrician is not needed when reconfiguration is desired. 
         [0026]    An alternate embodiment is shown in  FIG. 11 . Each photovoltaic module  123  is constructed as previously disclosed, however, a different electrical connector arrangement is employed. All of the electrical connectors  125  between adjacent modules  123  in the present embodiment have a generally flat and cube-like mating surface or pad protruding through their cases  127 . The mating pad of each electrical connector is magnetic such that it will attract an opposite electrical connector from a different module for use along one of the desired axes. Thus, the magnetic nature of the electrical connectors serves to both act as the sole way of connecting together the adjacent modules while also carrying electricity therebetween. These magnetic electrical connectors are attachable and removable in a tool-free and quick-connect manner in less than ten seconds. 
         [0027]    While various constructions of the present reconfigurable photovoltaic panels have been disclosed, it should be appreciated that other variations are possible. For example, while stamped metal male and female electrical connectors have been disclosed, it should be understood that extruded, cast or other methods of making mating electrical connectors may be employed as long as they function like those discussed herein. Furthermore, it is envisioned that additional electronics and/or electrical circuits can be employed within each photovoltaic module as long as they function as essentially described. It is also envisioned that a single pin electrical connector can be employed along the voltage axis, however, two generally parallel electrical connectors from each edge provide a more stable module-to-module securing interconnection. Moreover, while two adjacent electrical connectors are shown on each edge of the module, it should be appreciated that additional electrical connectors may also be provided should extra stability or circuits require such. Additionally, features of each embodiment may be interchanged with and added to features of the other embodiments in an interchangeable manner; for example and not by way of limitation, the magnetic electrical connectors can be employed with the flexible or rigid photovoltaic cells, while the indicator light feature can be provided on the flexible, rigid or magnetic embodiments. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are intended to be included within the scope and spirit of the present invention.