Abstract:
A socket protective cover capable of preventing single-opening insertions includes a housing, a sliding base and covers. The housing has insertion openings. The sliding base is capable of transverse displacement in the housing, and has restoring elasticity. The covers are also provided with restoring elasticity, and have blocking members for extending into the insertion openings of the housing. When the blocking members at the covers are not simultaneously pushed and departed from the insertion openings, the other blocking member not pushed away from the insertion opening remains in the insertion opening and blocks sideward movements of the sliding base, thereby forbidding an alien object from pushing away the blocking members and thus preventing the alien object from entering the socket.

Description:
BACKGROUND OF THE INVENTION 
   (a) Field of the Invention 
   The invention relates to a socket protective cover capable of preventing single-opening insertion, and more particularly, to a socket protective cover having covers capable of pivotally rotating in a sliding base for blocking members to block in insertion openings of a housing, thereby preventing entries of alien objects and accidental electric shocks. 
   (b) Description of the Prior Art 
   A common wall socket or an extension wire socket is generally provided with at least one set of receptacle, wherein each set of receptacle has two or three insertion openings. However, several drawbacks are found after studying the aforesaid prior socket. First of all, the “open” socket lacks protective measures, and accidental electric shocks are repeated occurrences among children caused by curiosity. Secondly, the prior socket is an open structure as described, with conductive straps at an interior thereof mostly being conductive materials such as copper. These conductive materials are often formed with aerugo resulted from humidity for being exposed in air over long periods of time, or accumulated with dust, and hence conductive efficiencies thereof become affected. Therefore, the prior socket has potential hazards to a certain degree, and can hardly be accounted as an ideal design when put to use. 
   SUMMARY OF THE INVENTION 
   The primary object of the invention is to provide a socket protective cover for blocking invasions of dust and preventing single-opening insertions of objects, thereby effectively avoiding accumulation of dust on conductive straps as well as accidental electric shocks. 
   To accomplish the aforesaid object, the invention comprises a housing, a sliding base and covers. The housing is provided with insertion openings. The sliding base is located in the housing to transversely displace therein, and has restoring elasticity. The covers are similarly provided with restoring elasticity, and have blocking members that can extend into the insertion openings of the housing. When pins of a plug simultaneously push against the blocking members at the covers, the covers are pivotally rotated on the sliding base and become tilted. Forces of the pins of the plug continuously imposed upon the covers then push the covers and also displace the sliding base sideward, such that the pins of the plug push open the covers and become inserted into the socket. However, when the blocking members at the covers are not simultaneously pushed and departed from the insertion openings, a blocking member not pushed away from the insertion opening is yet blocked in the insertion opening and prevents the sliding base to move sideward, thereby prohibiting an alien object from pushing open the covers. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows an exploded elevational view according to the invention. 
       FIG. 2  shows a sectional view according to the invention. 
       FIG. 3  shows a schematic view of an embodiment according to the invention. 
       FIG. 4  shows a schematic view according to the invention being inserted by a plug. 
       FIG. 5  shows a schematic view according to the invention being inserted by an alien object. 
       FIG. 6  shows a schematic view of the sliding base and the lower housing being assembled in a second embodiment according to the invention. 
       FIG. 7  shows a sectional view of a second embodiment according to the invention. 
       FIG. 8  shows a sectional view of a third embodiment according to the invention. 
       FIG. 9  shows a sectional view of a fourth embodiment according to the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   To better understand the invention, detailed descriptions shall be given with the accompanying drawings hereunder. 
   Referring to  FIG. 1 , the invention comprises a housing  1 , a sliding base  2 , and a covers  3 . 
   The housing  1  is consisted of upper and lower housings  11  and  12 . The upper and lower housings  11  and  12  are assembled by means of embedding, ultrasonic and screws; and are provided with two corresponding insertion openings  13  and  14  at outer sides thereof, respectively. The upper housing  11  further has two downwardly projecting fixing portions  15  at appropriate positions at an inner side thereof and next to the two insertion openings  13 . Each of the two fixing portion  15  has a spring  16  transversely disposed. 
   The sliding base  2  is assembled in the housing  1 ; that is, between the upper and lower housings  11  and  12 . The sliding base  2  is a hollow structure, and has two notches  21  at each of two side walls thereof. 
   The two covers  3  are disposed across and on the notches  21  at the side walls of the sliding base  2 , respectively. Each cover  3  has a spindle  31  protruding at two sides thereof, respectively, a blocking member  31  at a top portion thereof, and a pressing member  33  at a bottom portion thereof. 
   Referring to  FIG. 2 , to assemble the invention, the spindles  31  of the two covers  2  are placed in the notches  21  at the two sides of the sliding base  2 , and the sliding base  2  is assembled in the housing  1  (between the upper and lower housings  11  and  12  in this embodiment). Thus, the pressing members  33  at the bottom portions of the two covers  3  are butted against the springs  16  at the upper housing  11 , the blocking members  31  at the top portions of the upper housing  11  are blocked in the insertion openings  13  of the upper housing  11 , and the upper and lower housings  11  and  12  are sealed, joined and fastened. 
   Referring to  FIGS. 3 and 4 , to use the invention, the housing  1  is fastened in a fixing recess A 1  of a socket A, and the insertion openings  14  of the lower housing  12  are aligned with conductive straps A 3  in a casing A 2  of the socket A. When two pins B 1  of a plug B are inserted into the two insertion openings  14  of the lower housing  12 , the two pins B 1  of the plug B are simultaneously pushed against and instantaneously move the two blocking members  32  at the covers  3  downward At this point, the two covers  3  are rotated in the sliding base  2  due to circular spindles  31  thereof. When the blocking members  33  at the two covers  3  are departed from the insertion openings  13  in a downward direction, the pins B 1  are allowed to continuously move downward. Presently, the pins B 1  force the covers  3  to tilt and push against the lower housing  12 . The pins B 1  keep on imposing forces and generate a sideward thrust upon the tilted covers  3 , such that the two covers  3  are displaced transversely, and meanwhile the pressing portions  33  at the bottom portions of the covers  3  are pressed against the two springs  16 . The two spindles  31  at the two sides of the covers  3  are placed into the notches  21  at the two sides of the sliding base  2 , and therefore the two covers  3  are able to simultaneously drive the sliding base  2  to move sideward when being transversely displaced. Hence, the two pins B 1  are proceeded downward, penetrated through the insertion openings  14  of the lower housing  12 , and inserted into the conductive straps A 3  at the casing A 2  of the socket A for conduction and acquiring power. When the pins B 1  of the plug B are withdrawn, using restoring elasticity of the springs  16 , the two covers  3  are able to push the pressing members  33  of the two covers  3 , and restoring the sliding base  2  back to an original position thereof by driving and transversely moving the sliding base  2 , as well as recovering the blocking members  32  at the two covers  3  back to original status thereof as blocking in the insertion openings  13  of the upper housing  11 . 
   Referring to  FIG. 5 , when an alien object C is inserted into one of the insertion openings  13  of the upper housing  11 , only the blocking member  32  at the specific cover  3  is pushed and moved downward, whereas the blocking member  32  at the other cover  3  remains still and continues blocking in the other insertion opening  13 . The blocking member  32  moved downward drives and rotates the cover  3  in the sliding base  2  regarding the spindles  31  as a center thereof. However, when the cover  3  is rotated, the other blocking member  32  is yet blocked in the insertion opening  13  for that the other cover  3  is not rotated. Next, the sliding base  2  does not receive simultaneous transverse displacement and thrust of both the covers  3 , and is thus incapable to move transversely, either. As a result, the blocking member  32  being pushed by the alien object C cannot be successfully moved sideward by still blocking below the alien object C, and the alien object C is incapable of keeping on pushing downward. Consequently, the alien object C fails to penetrate through the insertion openings  14  of the lower housing  12  to insert into the conductive straps A 3  at the casing A 2 , thereby effectively preventing accidental electric shocks. 
   Referring to  FIGS. 6 and 7  showing a second embodiment according to the invention, upper and lower housings  41  and  42  of a housing  4  have insertion openings  411  and  421 , respectively. The upper housing  41  further has a fixing portion  43  and a spring  44  at a top portion of an inner side thereof. An interior (between the upper and lower housing  41  and  42  in this embodiment) of the housing  4  is disposed with a sliding base  45 . The sliding base  45  has one outer edge thereof butted against one end of the spring  44 , and is provided with two covers  46  at an interior thereof. A blocking member  47  at each cover  46  is blocked in the insertion openings  422 , respectively. Spindles  48  at two sides of the two covers  46  are accommodated by a torsion spring  49 , respectively. Each torsion spring  49  has one end thereof fixed at a side wall of each cover  46 , whereas the other end thereof fixed at an inner wall of the sliding base  45 . Hence, the housing  4  is fastened in the fixing recess A 1  at the socket A, and the insertion openings  421  of the lower housing  42  are aligned with the conductive straps A 3  at the casing A 2  of the socket A. When inserting a plug under normal circumstances, pins of the plug shove the two covers  3  for transverse displacement, and the torsion springs  49  at the spindles  48  of the covers  46  are curled up. Using the transverse displacement of the covers  46 , the sliding base  45  is further pushed for pressing against the springs  44 , so as to smoothly complete the insertion. When withdrawing the plug, through elastic restoring forces of the torsion springs  49  and the springs  44 , the sliding base  45  is recovered to an original position thereof via the covers  46 . When an alien object is invaded into one of the insertion openings  411 , the blocking member  47  at the cover  46  is yet blocked in the other insertion opening  411 , thereby similarly accomplishing prevention of invasions of alien objects by having the sliding base  45  remain unmoved. 
   Referring to  FIG. 8  showing a third embodiment according to the invention coordinating with a socket  5  having a different structure, a housing in this embodiment only consists of an upper housing  56  but not a lower housing. A casing  51  of the socket  5  has conductive straps  52  at an interior thereof. An upper portion of the casing  51  is for directly placing a sliding base  53 , which has covers  55  placed across on notches  54  at two side walls thereof. The housing (the upper housing  56 ) is covered on the socket  5 , and has two insertion openings  57  at an outer side thereof for corresponding with positions of the conductive straps  52 . The upper housing  56  further has two downwardly projecting fixing portions  58  at appropriate positions at an inner side thereof and next to the two insertion openings  57 . Each of the two fixing portion  58  has a spring  59  transversely disposed. Using the above structures, the upper housing  56  is directly covered onto the socket  5 , and members including the sliding base  53  and the covers  55  are assembled in the housing (between the upper housing  56  and the casing  51 ), thereby accomplishing similar effects as other aforesaid embodiments. 
   Referring to  FIG. 9  showing a fourth embodiment according to the invention coordinating with a socket  6  having a different structure, a housing only consists of an upper housing  68  but not a lower housing in this embodiment. A casing  61  of the socket  6  has conductive straps  62  at an interior thereof, and two projecting fixing portions  63  at a top portion thereof. Each of the two fixing portion  63  has a spring  64  transversely disposed. Outer peripheries of the two fixing portion  63  are for placing a sliding base  65 . Covers  67  are placed across on notches  66  at two side walls of the sliding base  65 . The housing (the upper housing  68 ) is covered onto the socket  6 , and has insertion openings  69  provided at an outer side thereof for corresponding with positions of the conductive straps  62 . Using the aforesaid structure, members including the sliding base  65  and the covers  67  are assembled in the housing (between the upper housing  68  and the casing  61  in this embodiment); thereby accomplishing similar effects as other aforesaid embodiments. 
   Conclusive from the above descriptions, the invention has the following excellences:
     1. When one of the insertion openings is inserted by an alien object, the cover in the insertion opening being inserted is incapable of pushing and moving the sliding base, while the blocking member at the other cover remains blocked in the corresponding insertion opening. Hence, the invention provides excellent safety precautions by prohibiting single-opening insertions of alien objects and thus accidental electric shocks.   2. When withdrawing a plug, the covers automatically cover the insertion openings, and therefore provide dust-proof effects.   3. The invention may be implemented by coordinating with sockets of various styles for offering manufacturing and assembly with diversification. The structure according to the invention has a wide range of applicability and can be applied in extension sockets and wall sockets.   

   It is of course to be understood that the embodiments described herein are merely illustrative of the principles of the invention and that a wide variety of modifications thereto may be effected by persons skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims.