Patent Publication Number: US-6217353-B1

Title: Structure of a safety receptacle

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention is related to an improvement in the structure of a safety receptacle and in particular to one which is simple in construction and easy to assemble. 
     2. Description of the Prior Art 
     Referring to FIG. 1, the conventional safety receptacle  1  generally includes a body portion, an upper slide  11 , a lower slide  12  and two springs  13 . The body portion is formed with two slots  14  at the top and a passage  10  in communication with the two slots  14 . The upper slide  11  is first engaged with the lower slide  12  and then fitted into the passage  10 . The two springs  13  are used for urging the upper slide  11  and the lower slide  12  to move in opposite directions to close the slots  14 . However, it is very difficult to mount the springs  13  on the slides  11  and  12  in such a small space thereby lowering the efficiency in assembly and reducing the production rate. In addition, the slides  11  and  12  are of different structures which will increase the cost and difficulty in assembly. 
     Therefore, it is an object of the present invention to provide an improved receptacle which can obviate and mitigate the above-mentioned drawbacks. 
     SUMMARY OF THE INVENTION 
     This invention is related to an improvement in the structure of a safety receptacle. 
     According to a preferred embodiment of the present invention, a safety receptacle includes a casing having a top formed with two slots, a pair of rectangular slides arranged within the casing in opposite directions, each of the slides having three sides formed with a plurality of semi-circular projections and another side with a resilient member, each of the slides having a first opening formed with an inclined shoulder and a second opening formed with a flat shoulder, each of the slides further having at top formed with a plurality of protuberances and a bottom formed with a rib, and a bottom cover configured to engage with a bottom of the casing and having a supporting portion for supporting the slides. 
     It is the primary object of the present invention to provide an improvement in the structure of a safety receptacle which is simple in construction. 
     It is another object of the present invention to provide an improvement in the structure of a safety receptacle which is easy to assemble. 
     It is still another object of the present invention to provide an improvement in the structure of a safety receptacle which is low in cost. 
     It is still another object of the present invention to provide an improvement in the structure of a safety receptacle where insertion of an object will cause no damage to the person inserting it. 
     It is a further object of the present invention to provide an improvement in the structure of a safety receptacle which is fit for mass production. 
     The foregoing objects and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts. Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of a prior art safety receptacle; 
     FIG. 2 is an exploded view of a safety receptacle according to the present invention; 
     FIG. 2A is an enlarged fragmentary view of FIG. 2; 
     FIG. 2B is a bottom perspective view of the slide; 
     FIG. 3 is a cutaway view showing the structure of the casing; 
     FIG. 4 is a sectional view illustrating how the slides are mounted within the casing; 
     FIG. 5 is sectional view illustrating the relative positions of the component parts of the present invention; 
     FIG. 5A is an enlarged fragmentary view of FIG. 5; 
     FIG. 6 is a sectional view illustrating the relative positions of the component parts of the present invention; and 
     FIGS. 7,  8  and  9  illustrate the working principle of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings. Specific language will be used to describe same. It will, nevertheless, be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
     With reference to the drawings and in particular to FIGS. 2,  2 A,  2 B and  3  thereof, the safety receptacle according to the present invention generally comprises a casing  2 , a pair of slides  3  and a bottom cover  4 . The casing  2  is formed with two slots  25  at the top and two vertical partitions  21  at the interior thereby forming a chamber (shown but not numbered). The slide  3  is a rectangular member formed with a plurality of semi-circular projections  31  at three sides and a resilient member  32  at the other side. The resilient member  32  is integrally formed with the slide  3 . The body portion of the slide  3  is formed with a first opening  34  close to the resilient member  32  and a second opening  33  close to the opposite side. The first and second openings  34  and  33  are formed with an inclined shoulder  341  and a flat shoulder  331 , respectively. The slide  3  is further formed with a plurality of protuberances  35  at the top and a rib  36  at the bottom. The bottom cover  4  is configured to engage with the bottom of the casing  2  and provided with a supporting portion  41  for supporting the slides  3 . The supporting portion  41  has recesses for receiving electrical terminals which are well known to the art and have no need to be described here in detail. 
     In assembly, the two slides  3  are arranged within the casing  2  in opposite directions so that the slides  3  are movably fitted within the chamber formed by the two partitions  21  of the casing  2  (see FIG.  4 ). The semi-circular projections  31  are used for reducing the friction between the slide  3  and the partitions  21 . The rib  36  and the protuberance  35  are also used for reducing the friction produced when the slide  3  is moved (see FIGS. 5,  5 A and  6 ). Then, electrical terminals  7  are mounted on the supporting portion  41  of the bottom cover  4 . Finally, the bottom cover  4  is engaged with the bottom of the casing  2 . 
     Referring to FIG. 7, when the blades  51  of an electrical plug (not shown) are inserted through the slots  25  of the casing  2  into the openings  33  and  34  of the slide  3 , the blades  51  will push the upper slide  3  to move the left and the lower slide  3  to the right with respect to FIG. 7 thereby aligning the openings  34  and  33  of the upper and lower slides  3  and therefore enabling the blades  51  to be inserted through the openings  34  and  33  to engage with electrical terminals (not shown) mounted in the supporting portion  41  of the bottom cover  4 . As the blades  51  of the electrical plug are pulled out of the casing  2 , the resilient members  32  of the slides  3  will push the slides  3  to move in opposite directions thereby closing the openings  34  and  33 . When a metal object  61  is inserted through the slot  25  at the left side (with respect to FIG.  8 ), the flat shoulder  331  of the opening  33  of the upper slide  3  will block the metal object  61  from passing through the opening  33  thereby causing no damage to the person inserting it (see FIG.  8 ). Likewise, when the metal object  61  is inserted through the slot  25  at the right side (with respect to FIG. 9) into the opening  34  of the upper slide  3 , the flat shoulder  331  of the opening  33  of the lower slide  3  will block the metal object  61  from passing through the opening  33  thus keeping the person inserting it from danger. 
     It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. 
     While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.