Abstract:
An electric outlet dust protective structure used in an electric outlet to close the front opening of the housing of the electric outlet when the electric outlet is not inserted with an electric plug is disclosed to include a top dust cover, which has a top finger strip and an actuating block with two sloping side edges, left and right side dust covers each having a respective sloping top guide face maintained in contact with the sloping side edges of the actuating block and a respective guide groove coupled to a respective guide rod at the top dust cover for easy downward movement with the top dust cover to open the front opening of the housing, and two spring members that support the left and right side dust covers and the top dust cover in the close position to close the front opening of the housing.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention relates to electric outlets and more specifically, to an electric outlet dust protective structure, which uses a top dust cover and two side dust covers to close the front opening of the housing of the electric outlet against outside dust and two compression springs to support the dust covers in the close position. 
       FIGS. 1˜3  show an electric outlet dust protective structure according to the prior art. According to this design, the electric outlet dust protective structure is comprised of an electric outlet housing  911 , a dust cover  912 , a torsional spring  913 , a back cover  914 , and a terminal holder body  915 . This design of electric outlet dust protective structure has drawbacks as follows:
         1. When connecting an electric plug to the electric outlet, the user must open the terminal holder body  915  by lifting the dust cover  912  to compress the torsional spring  913 , however lifting the dust cover  912  requires much effort.   2. The torsional spring  913  wears quickly with use. When started to wear, the torsional spring  913  may be unable to hold the dust cover  912  in the close position.       
       FIGS. 4˜6  show another design of electric outlet dust protective structure according to the prior art. According to this design, the electric outlet dust protective structure is comprised of an electric outlet housing  921 , a main dust cover  922 , an auxiliary dust cover  923 , a compression spring  94 , a locating plate  925 , a back cover  926 , and a terminal holder body  927 . When opening the electric outlet, press the main dust cover  922  downwards to lower the auxiliary dust cover  923 . This design requires less effort to open the dust covers  922 ,  923 . However, if the electric outlet is installed in a corner area behind a furniture or an object, it is still inconvenient to approach the main dust cover  922 . 
     Therefore, it is desirable to provide an electric outlet dust protective structure that eliminates the aforesaid drawbacks. 
     The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide an electric outlet dust protective structure, which can conveniently be operated with less effort. To achieve this and other objects of the present invention, the electric outlet dust protective structure is installed in the housing of an electric outlet and adapted to close the front opening of the housing of the electric outlet against outside dust when the module jack of the electric outlet is not inserted with an electric plug. The electric outlet dust protective structure comprises a top dust cover, which has a top finger strip and an actuating block with two sloping side edges, left and right side dust covers each having a respective sloping top guide face maintained in contact with the sloping side edges of the actuating block and a respective guide groove coupled to a respective guide rod at the top dust cover for easy downward movement with the top dust cover to open the front opening of the housing, and two spring members that support the side dust covers and the top dust cover in the close position to close the front opening of the housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is an exploded view of an electric outlet dust protective structure according to the prior art. 
         FIG. 2  is an elevational assembly view of  FIG. 1 . 
         FIG. 3  is a back side plain view of the electric outlet dust protective structure shown in  FIG. 1 . 
         FIG. 4  is an exploded view of another design of electric outlet dust protective structure according to the prior art. 
         FIG. 5  is a front view of the electric outlet dust protective structure shown in  FIG. 4 . 
         FIG. 6  is an elevational assembly view of the electric outlet dust protective structure shown in  FIG. 4 . 
         FIG. 7  is an exploded view of an electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 8  is an oblique front elevation of the assembly of the top dust cover and the two side dust covers of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 9  is an oblique rear elevation of assembly of the top dust cover and the two side dust covers of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 10  is a sectional assembly view of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 11  is a schematic sectional view of the first embodiment of the present invention, showing the open status of the electric outlet dust protective structure. 
         FIG. 12  is an oblique rear elevation of the assembly of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 13  is an oblique front elevation of the assembly of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 14  is sectional elevation of the assembly of the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 15  is an elevational view of the first embodiment of the present invention, showing the open status of the electric outlet dust protective structure (I). 
         FIG. 16  is an elevational view of the first embodiment of the present invention, showing the open status of the electric outlet dust protective structure (II). 
         FIG. 17  is an elevational view of the face panel for the electric outlet dust protective structure according to the first embodiment of the present invention. 
         FIG. 18  is an exploded view of an electric outlet dust protective structure according to the second embodiment of the present invention. 
         FIG. 19  is another exploded view of the second embodiment of the present invention (the cover shell not shown). 
         FIG. 20  is an elevational assembly view of the electric outlet dust protective structure according to the second embodiment of the present invention. 
         FIG. 21  is a rear elevational view in an enlarged scale of a part of the electric outlet dust protective structure according to the second embodiment of the present invention. 
         FIG. 22  is an oblique front elevation of the assembly of  FIG. 21 . 
         FIG. 23  is an exploded front view of an electric outlet dust protective structure according to the third embodiment of the present invention. 
         FIG. 24  is an elevational assembly view of the electric outlet dust protective structure according to the third embodiment of the present invention. 
         FIG. 25  is an exploded rear side view of the electric outlet dust protective structure according to the third embodiment of the present invention. 
         FIG. 26  is an assembly view of  FIG. 25 . 
         FIG. 27  is a front view of  FIG. 26 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 7˜17 , an electric outlet dust protective structure in accordance with the first embodiment of the present invention is shown comprised of a top dust cover  1 , left and right side dust covers  2 ,  3 , left and right guide rails  4 ,  5 , two compression springs  10 , and an electric outlet formed of a housing  6  and a module jack (terminal holder body)  60 . The housing  6  is comprised of a casing  62 , a back cover  63 , and a faceplate  64 . 
     The top dust cover  1  comprises a flat base  11 , a finger strip  111  extended from the top side of the flat base  11  at right angles and inserted through the front opening  61  of the casing  62  of the housing  6  from the inside toward the outside, an actuating block  112  protruded from the front side of the flat base  11 , the actuating block  112  having two sloping side edges  1121 ,  1122  sloping downwardly inwards and then meeting each other at a point, two guide rods  113 ,  114  perpendicularly extended from the front side of the flat base  11  and respectively spaced from the sloping side edges  1121 ,  1122  of the actuating block  112  at a space, two side wings  115  symmetrically disposed at two opposite lateral sides of the flat base  11 , and two locating rods  1151  respectively downwardly extended from the side wings  115 . 
     The left and right guide rails  4 ,  5  are provided at the top of the bottom wall of the casing  62  of the housing  6 , each having a sloping guide face  41  or  51  sloping downwardly inwards (see  FIG. 7 ). 
     The compression springs  10  are respectively supported between the top dust cover  1  and the bottom wall of the casing  62  of the housing  6 , each having a top end  101  respectively fastened to the locating rods  1151  of the top dust cover  1  and a bottom end  102  respectively fastened to a respective locating block  621  at the bottom wall of the casing  62  of the housing  6 . 
     The left and right side dust covers  2 ,  3  each have a sloping top guide face  22  or  32  fitting the sloping side edges  1121 ,  1122  of the actuating block  112  of the top dust cover  1 , a sloping bottom guide edge  23  or  33  respectively kept in contact with the sloping guide faces  41 ,  51  of the left and right guide rails  4 ,  5  at the bottom wall of the casing  62  of the housing  6 , and a back sliding groove  21  or  31  respectively coupled to the guide rods  113 ,  114  of the top dust cover  1 . Each back sliding groove  21  or  31  has a sloping groove section  211  or  311 , and a vertical groove section  212  or  312  vertically downwardly extended from the lowest end of the sloping groove section  211  or  311 . 
     The compression springs  10  impart an upward pressure to the side wings  115  of the top dust cover  1 , thereby forcing the finger strip  111  against the top side of the periphery of the front opening  61  of the housing  6 , and therefore the actuating block  112  and the front faces  20 ,  30  of the left and right side dust covers  2 ,  3  block the front opening  61  of the housing  6  against outside dust (see  FIGS. 13 and 14 ). When wishing to connect a muddle plug to the module jack (terminal holder body)  60  in the housing  6 , press the finger strip  111  of the top dust cover  1  to force the sloping side edges  1121 ,  1122  of the actuating block  112  of the top dust cover  1  against the sloping top guide faces  22 ,  32  of the left and right side dust covers  2 ,  3 . Therefore, the left and right side dust covers  2 ,  3  are respectively moved along the sloping guide faces  41 ,  51  of the left and right guide rails  4 ,  5  at the bottom wall of the casing  62  of the housing  6 , and at the same time, the guide rods  113 ,  114  of the top dust cover  1  are moved downwards along the back sliding grooves  21 ,  31  of the left and right side dust covers  2 ,  3 . When the finger strip  111  of the top dust cover  1  touched the bottom side of the periphery of the front opening  61  of the housing  6  (see  FIG. 16 ), the guide rods  113 ,  114  of the top dust cover  1  are moved to the bottom ends of the vertical groove sections  212 ,  312  of the back sliding grooves  21 ,  31  and stopped against the left and right guide rails  4 ,  5  (see  FIG. 11 ). On the contrary, when released the hand from the finger strip  111  of the top dust cover  1 , the compression springs  10  immediately push the top dust cover  1  upwards, and the guide rods  113 ,  114  of the top dust cover  1  are moved upwards from the vertical groove sections  212 ,  312  of the back sliding grooves  21 ,  31  of the left and right side dust covers  2 ,  3  into the respective sloping groove sections  211 ,  311 , and therefore the left and right side dust covers  2 ,  3  are respectively obliquely moved upwards and returned to the respective former positions to close the front opening  61  of the housing  6  with the top dust cover  1  (see  FIGS. 10 and 13 ). 
     The back cover  63  is fastened to the casing  62  of to hold the module jack (terminal holder body)  60  inside the housing  6 , keeping the insertion hole  601  of the module jack (terminal holder body)  60  aimed at the front opening  61  of the housing  6 . The back cover  63  has two hooks  631  respectively fastened to respective retaining holes  67  at two sides of the casing  62 . After installation of the back cover  63  and the module jack (terminal holder body)  60  in the casing  62 , the top dust cover  1  and the left and right side dust covers  2 ,  3  are movably supported between the front side of the module jack (terminal holder body)  60  and the front wall  620  of the casing  62  of the housing  6 . The casing  62  further comprises a plurality of retaining flanges  622  symmetrically disposed at two sides of the front opening  61 . The faceplate  64  is fastened to the front side of the casing  62 , having an opening  641  corresponding to the front opening  61  of the casing  62  and a plurality of recessed retaining portions  642  symmetrically disposed at two sides of the opening  641  and respectively forced into engagement with the retaining flanges  622  (see  FIG. 17 ). 
     The two locating plates  66  are vertically mounded inside the housing  6  to support the compression springs  10 , each having a bottom end  661  respectively engaged into a respective locating hole  662  in the bottom wall of the casing  62  of the housing  6  behind the locating blocks  621  and a locating hole  662  disposed near the top and respectively coupled to a respective locating rod  6201  at the front wall  620  of the casing  62  of the housing  6  (see  FIG. 10 ). 
       FIGS. 18˜22  show an electric outlet dust protective structure according to the second embodiment of the present invention. The electric outlet dust protective structure is comprised of a top dust cover  1 , left and right side dust covers  2 ,  3 , left and right guide rails  4 ,  5 , two compression springs  10 , and an electric outlet formed of a housing  7  and a module jack (terminal holder body)  60 . According to this embodiment, the top dust cover  1 , the left and right side dust covers  2 ,  3 , the left and right guide rails  4 ,  5 , and the springs  10  are same as the like members shown in the aforesaid first embodiment of the present invention. However, the housing  7  is shaped like a box comprised of a base block  72 , a bottom frame  73  fastened to the bottom side of the base block  72 , and a cover shell  74 . The left and right guide rails  4 ,  5  are provided at the front side of the bottom frame  73  and have the respective sloping guide faces  41 ,  51  disposed in contact with the sloping bottom guide edges  23 ,  33  of the left and right side dust covers  2 ,  3 . The base block  72  comprises a recessed accommodating chamber  720 , which accommodates the module jack (terminal holder body)  60 , an upright front wall  722 , and an opening  721  in the upright front wall  722 . The cover shell  74  has an opening  741  in the front side. When assembled, the opening  721  of the upright front wall  722  and the opening  741  of the cover shell  74  form a front opening  71  in line with thee insertion hole  601  of the module jack (terminal holder body)  60 , and the top dust cover  1  with the left and right side dust covers  2 ,  3  are movably disposed between the module jack (terminal holder body)  60  and the upright front wall  722  of the base block  72 . 
     Further, the bottom frame  73  comprises two upright rods  732  that hold the compression springs  10  in place, an upright partition plate  725  spaced behind the upright front wall  722  and defining with the upright front wall  722  a space  728  for receiving the top dust cover  1  and the left and right side dust covers  2 ,  3 , and a bottom opening  727  in communication with the space  728  for accommodating the left and right guide rails  4 ,  5 . 
       FIGS. 23˜27  show a third embodiment of the present invention. This embodiment is a combination of two electric outlet dust protective structures made according too the aforesaid first embodiment of the present invention. According to this embodiment, a rack  83  is provided at the back side of the faceplate  8  to hold two dust shutter units each formed of a top dust cover  1 , a left side dust cover  2 , a right side dust cover  3 , and two compression springs  10 . The faceplate  8  comprises two locating flanges  827  perpendicularly extended from the back wall at different elevations, and two insertion holes  81  disposed at different elevations between the locating flanges  827 . The locating flanges  827  each have a plurality of retaining holes  8271 . The rack  83  comprises a plurality of hooks  831  respectively fastened to the retaining holes  8271 , and a plurality of locating rods  832  that support the compression springs  10 . 
     A prototype of electric outlet dust protective structure has been constructed with the features of  FIGS. 7˜27 . The electric outlet dust protective structure functions smoothly to provide all of the features discussed earlier. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.