Abstract:
The protective electronic prototyping enclosure is conveniently formed to accommodate various prototype electronic projects. Openings in the enclosure may be accurately formed and markings can be neatly and precisely formed by on a paper label printed by using the computer. Variable panels are provided for covering spaces between electrical components located adjacent to the side panels of the enclosure.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an enclosure for constructing prototype electrical and electronic devices. 
     2. Background Art 
     In the design of electrical and electronic circuits, particularly for circuit developers and students, commonly after the circuit design has been established, a prototype is built to test the operation and feasibility of the circuit design. The prototype not only must be functional to provide the required purposes, it must also be able to withstand various inadvertent mishaps in its handling during its construction with various electrical components, and changes of electrical components which may be required during its testing stage, as well as when submitting the prototype for evaluation by other people. In order to preserve the integrity of the circuit design, a secure protective project enclosure must be provided. Heretofore, rectangular plastic boxes are employed for fabricating prototype electrical and electronic devices. The rectangular plastic box normally consists of a simple rectangular plastic casing and a rectangular plastic top cover, or alternatively two U-shaped rectangular half shells engageable with one another as top and bottom half shells to form a rectangular box. Various openings must be cut by the prototype builder in the side, bottom and top panels of the box to accommodate the operating parts of various electrical components such as switches, connectors, power receptacles, rotary shafts of rheostats, and numerical or graphic displays, etc., which are commonly used in making an electrical circuit. These electrical components are usually mounted on a printed circuit board located inside the box. It has been very problematic in forming such openings in the various side, top and bottom panels of the plastic box since these openings are formed commonly by drilling, sawing, and cutting the plastic panels at the required locations; and the plastic panels can easily break or crack in the drilling, sawing and cutting processes. It is particularly problematic to carry out these processes with a relatively small size plastic box for use in enclosing a relatively small circuit design, because of the difficulties in retaining and mounting the small plastic box securely during the sawing, cutting and drilling processes. These processes are difficult and sometimes impossible to carry out due to the restricted space available for inserting the drill and/or the cutting tool inside a relatively small box. Moreover, in order to form any circular opening larger than the size of a standard drill bit, or in forming openings other than a circular shape, the opening must first be formed by marking the outline of the required opening on the plastic panel and then numerous holes are drilled along the outline, and then the area defined by the numerous holes is punched out to form the opening. The opening thus formed invariably has jagged edges. In order to refine the shape of the opening, the jagged edges must then be painstakingly filed down by hand to obtain the desirable smooth edges. Often the filing process would result in a rather ugly irregularly shaped opening which ultimately renders an inferior appearance in the prototype device. 
     Furthermore, when a printed circuit board is employed in fabricating the prototype circuit, the circuit board is normally mounted in a horizontal manner inside the lower casing with the control and display electrical components mounted on top of the printed circuit board. These components have rotary shafts and/or slidable handles which must extend outside of the top panel of the enclosure to facilitate their operations. Accordingly, openings must be formed at the exact locations in the top panel for this purpose. It is extremely difficult to determine and to mark on the top panel of the plastic box accurately at the exact locations for forming the openings for accommodating the rotary shaft and slidable handle of these control and display electrical components. 
     Furthermore, operation markings such as a scale must be provided adjacent to opening for the rotary shaft and the slidable handle of the control components to guide or indicate their operations. Such operation markings are also difficult to provide on the plastic surface. Normally, such markings are either provided on an adhesive label applied on the plastic surface and located adjacent to the openings, or alternatively the markings are inscribed directly on the plastic surface adjacent to the openings. Since an adhesive label can easily fall off due to the deterioration of the adhesive or it may be defaced, while inscriptions of markings are difficult and time consuming to make, or to engrave neatly on the plastic surface. 
     Also, due to the limited space available in the protective plastic box, many electrical components such as connectors, switches, connection jacks, are necessarily located along the narrow space between the printed circuit board and the side panels inside the box, and a plurality of electrical wiring must be employed for directly connecting between the connection terminals of these electrical components and the printed circuit board. The plurality of electrical wiring connections are time consuming to make, and the connections are unreliable due to the tendency of damaging the wiring or shorting of the connection terminals. 
     SUMMARY OF THE INVENTION 
     It is a principal object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device in which openings can be accurately and readily formed without the use of powered tools. 
     It is another object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device having variable side panels for enclosing the spaces between electrical components located in the inside areas adjacent to the side edge portions of the box. 
     It is another object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device in which electrical components may be securely and readily located therein with a minimum number of electrical wiring connections. 
     It is another object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device having a clear plastic top panel made of a plastic material in which openings of selected shaped can easily be formed with a puncher. 
     It is still another object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device in which openings and labeling may be formed accurately and easily. 
     It is yet another object of the present invention to provide a protective box for fabricating a prototype electrical and electronic device in which a battery compartment is provided for installing several different standard types of batteries. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Reference is hereby made to the accompanying drawings which form part of the specification of the present invention. 
         FIG. 1  is a perspective top front and side elevation view of the electronic prototype enclosure of the present invention. 
         FIG. 2  is a bottom exploded view showing the component part of the top covering casing of the electronic prototype enclosure of the present invention. 
         FIG. 3  is an exploded top front and side elevation view with the top cover casing and the lower support base separated from one anther. 
         FIG. 4  is a perspective rear elevation view of the variable cover plate for covering space openings in the rear panel of the prototype enclosure of the present invention. 
         FIG. 5  is a perspective top and rear elevation view of the electronic prototype enclosure of the present invention with the top cover sheet removed and the variable cover plates separated from the rear of the enclosure. 
         FIG. 6  is a perspective top and rear elevation view of the lower support base with the electronic components separated from the rear edge area therefrom. 
         FIG. 7  is a perspective top and side elevation of the lower support base with the printed circuit board mounted thereon. 
         FIG. 8  is an exploded perspective top and rear elevation view with the printed circuit separated from the lower support base. 
         FIG. 9  is an exploded perspective bottom elevation view of the lower base support showing the battery compartments and the cover separated therefrom. 
         FIG. 10  is another exploded perspective bottom elevation view of the lower support base showing the construction of the battery compartments with various elements and batteries separated therefrom. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawings in which like reference numerals in the various views designate corresponding parts, the enclosure  10  of the present invention, consists of a top cover casing  11  and a lower support base  12  which are engageable with one another to form the enclosure  10 . The top cover casing  11  has downwardly extending skirting side walls  13 ,  14 ,  15 , and  16 . The side wall  13  may be provided with pre-formed cut-outs  17  and  18  for accommodating electrical components such as connection socket  19  and a power switch  20  mounted in the right edge area of the lower support base  12 . An elongated cut-out  21  is formed in the lower portion of the side wall  16  in order that electrical components may be located in the edge area  22  in the lower support base  12 . A groove  23  is formed in the lower edge of the side wall  16 . Mounting openings  24  and  25  may also be formed in the right side wall  13  for receiving mounting screws (not shown) for securing the top cover casing  11  to the lower support base  12  with threaded plates  26  and  27  provided in the right side of the lower support base  12 . Similar mounting openings  28  and  29 , shown in  FIG. 2 , may also be provided in the left side wall  14  of the top cover casing for the same purposes with screws engaging with threaded mounting plates  30  and  31  respectively provided in the left side of the lower support base  12 . Alternatively, flexible tabs instead of plates  26 ,  27 ,  30  and  31  may be provided at the lower support base  12  which would snappingly engage with depressions formed in the inner side wall of the  13  and  14  to secure the top cover casing and the lower support base together. 
     A large rectangular opening  32  is formed in the top of the top cover casing  11 . The rectangular opening  32  is bounded by a rectangular border frame  33 . Two transparent protective cover sheets  34  and  35  are located within the top cover  11  to rest against the rectangular border frame  33 , and it may be retained in place with a rectangular mounting frame  36  mounted to posts  37 ,  38 ,  39 ,  40 ,  41 , and  42  provided in the top cover casing  11 . The rectangular mounting frame  36  is provided with closed end slots  43 ,  44 ,  45 ,  46 ,  47 , and  48  having an opening formed in the closed end. The rectangular frame  36  is locatable within the top cover casing  11  with the closed end slots engaging with the posts  37 ,  38 ,  39 ,  40 ,  41  and  42  such that the rectangular mounting frame  36  may be secured to the inside of the top cover casing  11  with screws (not shown) for holding the cover sheets  34  and  35  under the rectangular border frame  33 . The cover sheets  34  and  35  may be provided by two thin clear PVC sheets such that openings of selected shapes may be easily made in the cover sheets  34  and  35  with a simple punching hand tool. Furthermore, locations for punching the openings may be accurately marked on a paper template such as with print out provided by a computer design, and the template is sandwiched between the cover sheets  34  and  35  to facilitate the formation of the openings precisely. Also, the formation of the openings on the cover sheets  34  and  35  with the punching hand tool may be carried out easily with the cover sheets separate from the top cover  11 , and errors in the formation of the openings may be quickly and simply corrected by replacing the cover sheets. 
     The lower support base  12  has upstanding side walls  49 ,  50 ,  51 , and  52  engageable with the front wall  15 , the two side walls  13  and  14  and the rear wall  52  of the top cover casing  11 . A plurality of slot openings  53  and  54  are formed in the upper edge of the rear wall  52  as best shown in  FIG. 5 . The slot openings  53  are preferably shorter in length than that of the slot openings  54 . A plurality of variable cover plates  55  are mountable to the rear of the enclosure  10 . The variable cover plate  55  has two lower leg portions  56  and  57  extending downwards from the lower edge of its two side portions, and an upstanding elongated ridge  58  is formed at its upper edge. The dimensions of the two lower leg portions  56  and  57  are equal to the dimensions of the slot openings  53  formed at the upper edge of the rear wall  52  of the lower support base  12  and the distance between the lower leg portions  56  and  57  are equal to the distance between the adjacent slot openings  53  such that a cover plate  55  may be mounted to the upper edge of the rear wall  52  by slidably engaging the two lower leg portions  56  and  57  with the adjacent slot openings  53 . The thickness and the height of the elongated ridge  58  of the cover plate  55  is equal to the width and depth of the groove  23  formed at the lower edge of the rear wall  16  of the top cover casing  11  such that the variable cover plate  55  will be mounted at the rear opening  21  and will be securely retained in place by the cooperation between the cover casing  11  and the lower support base  12  when the cover casing  11  and the lower support base  12  are mounted together. The flexible cover plate  55  is preferably made of a plastic material and has a plurality of vertical grooves  59  and horizontal grooves  60  formed in its inner wall such that the flexible cover may be severed along selected grooves to vary its width and/or height. 
     A plurality of electrical components such as a multi-port connector  61  and a communication network receptacle  62  may be located in the rear edge portion  52  of the lower support base  12 . These electrical components are commonly provided with connection terminal pins having spacing of less than 0.1 inch pitch between the terminal pins which are often also provided in slanted rows so that it is problematic to make electrical connection to these terminal pins with the standard main printed circuit board located in the enclosure with the prototype circuit constructed on the main printed circuit board, because the terminal eyelets of the standard printed circuit board have a standard spacing of 0.1 inch. Furthermore, providing insulated push-on connectors to the terminal pins of the electrical components or to solder the leads directly thereon are also problematic. In order to obviate this problem, the electrical components are provided on adapter boards  63  and  64  with the electrical components pre-mounted on these adapter boards  63  and  64  which are provided with a pattern of eyelet connectors specifically laid out to match the configurations of the terminal pins of the particular electrical components, so that connections may be made and soldered to the adaptor boards. The connections are then routed to a row of soldering eyelets having the standard 0.1 inch spacing between neighboring eyelets provided on the adaptor boards. Thus, a ribbon cable or a row of header pins may be used with the adaptor boards  63  and  64  for easy connection to be made with the main printed circuit board. The adapter boards  63  and  64  may be conveniently secured in the edge area of the lower support base  12  by snap engagement with flexible inverted L-shaped posts  65  or alternatively secured to upstanding mounting posts  66  provided in the rear edge portion  63  of the lower support case  12 . After the electrical components have been mounted to the enclosure  10 , a plurality of variable cover plates  55  may be shaped by severing selected portions of these plates along selected vertical and horizontal grooves  59  and  60  formed in these plates so as to vary their shape and dimension to conform with the spacing and openings between and around the electrical components. Thus, the plates  55  may be mounted in the enclosure  10  for covering the spacing and openings between and around the electrical components. A plurality of ventilation slots  67  may be formed at the bottom panel of the rear edge portion  63  of the lower support casing  12 . 
     A battery housing  68  is formed at the lower support casing  12 . The main printed circuit board  69  with the prototype circuit constructed thereon may be mounted on the bottom surface  70  of the battery housing  68 . A plurality of stand offs  71  and  72  are provided on the bottom surface  70  to space the printed circuit board  69  from the bottom surface  70 . The printed circuit board  69  is held in position with inverted L-shaped tabs  73  and  74  formed at the edge portion of the bottom surface  70  of the battery housing  68  and may also be additionally secured in place with screws to mounting posts  75 ,  76 ,  77  and  78 . 
     The battery housing  68  preferably has three compartments  79 ,  80  and  81  which have dimensions to accommodate a standard 9-volt battery  82  or two AA batteries  83 . A generally W-shaped pivotal plate  84  is located adjacent one end of each compartment and a generally similar W-shaped pivotal plate  85  is located immediately adjacent to the other end of the compartment. These pivotal plates  84  and  85  may be turned upwards for supporting two AA batteries located in the compartment. Alternatively, the plate  85  may be non-pivotal and is fixed in place for simplicity in operation. A bottom cover plate  86  is provided for covering the bottom opening of the battery compartment. 
     A template may be accurately and neatly printed by utilizing a computer program to provide locations for forming openings in the protective cover sheets  34  and  35  to accommodate the operative element of electrical components, such as a rheostat for adjusting frequency, and slidable switch for varying the frequency setting and display, located on the printed circuit board within the enclosure. The openings may be neatly formed by cutting or stamping in the transparent protective cover sheets  34  and  35  with a hand tool. Markings may also be produced by computer on a paper label  87  safely sandwiched between the protective cover sheets  34  and  35 . 
     While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.