Abstract:
The present invention relates to an electrical receptacle having a safety mechanism. The electrical receptacle includes a latch installed internally, where the latch is operated through a switch member positioned externally. The latch can be switched to a locking position or an unlocking position by the switch member. In the locking position, the plug is constrained to be unplugged or the plug is restricted to be inserted. In the unlocking position, the plug is free to be inserted or unplugged.

Description:
BACKGROUND OF INVENTION 
   1. Field of the Invention 
   The invention relates to an electrical receptacle having a safety mechanism for using in a fixed receptacle, a receptacle with extended line and other assorted receptacles. More particularly, the electrical receptacle is able to constrain a plug when it is inserted or prevent it from being taken off. 
   2. Description of the Prior Art 
   An electrical receptacle is connected with a plug of an electrical product for transferring electricity. In  FIG. 1 , two kinds of prior electrical receptacle  10  and  10 ′ are disclosed. One is fixed on the surface of buildings or objects and the other is a receptacle with an extended line without any surrounding limitation. 
     FIG. 2  illustrates the major components structure of the electrical receptacle  10 . As  FIG. 2  shows, the electrical receptacle  10  comprises a substance  12  and a plurality of holes  14  installed on the substance  12  for the pins  162  of an inserted plug  16 . A plurality of internal conductivity slices  22  transfer electricity to the electrical products (not shown). The shape and number of the holes  14  correspond with the pins  162  of the plug  16  according to the standard specification of each country. In  FIG. 2 , the plug  16  comprises two parallel pins  162  which is the specification in the U.S.A., Taiwan and Japan. In other cases, some countries or regions provide different plugs with a third pin and/or different shapes and positions of these pins.  FIG. 2  shows a twin pin plug merely as an illustration and not a limitation. 
   The conductivity slices  22  of the electrical receptacle  10  are made from an elastic and conductive material such as copper. Each of them has an open end  24  towards the outside enabling the pin  162  of the plug  16  to be inserted easily. The elasticity of the conductivity slices  22  can help to clip the pins  162  stably and avoid taking the plug  16  off through force. 
   There are many shortcomings and safety concerns in the prior art, however. Many electrical products, such as computers and DRAM are not tolerant to electrical interruption. If the plug comes off accidentally, the product will lose its data or damage its substance. 
   There have been some fixed plug locking apparatus like the electrical product cover of TW 555,272 and the fixed locking apparatus of U.S. Pat. No. 6,652,307. They all provide protection and fixing of plugs in certain situations. They cannot overcome the problem of the plug being fixed unstably, however, or they cannot restrict the electrical receptacle from undesired use. 
   SUMMARY OF INVENTION 
   It is therefore a primary objective of the claimed invention to provide an electrical receptacle to solve the above-mentioned problems. The invention is used with fixed plugs to prevent the plug from being taken off during use. Furthermore, the invention can prevent a plug from being inserted. 
   According to the claimed invention, an electrical receptacle having a safety mechanism comprises a switch member and at least one latch. The latch can be switched to a locking position or an unlocking position through the switch member directly or indirectly. When the latch is in the locking position, it prevents the pins of the plug from being inserted, (if the plug is loose), or the pins being removed, (if the plug is already inserted). Only when the latch changes into the unlocking position can the pins be inserted or taken off freely. 
   For this reason the major characteristic of the invention is the structure of the electrical receptacle. It can further be used with a safety cover with pins, and a safety cover installed on the electrical receptacle to avoid the holes of the electrical receptacle being used. 
   In other cases, the safety mechanism can be connected with a lock, further improving its safety. 
   These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIGS. 1 and 2  are the component diagrams of an electrical receptacle according to the prior art. 
       FIG. 3  is the component diagram of an electrical receptacle according to the present invention. 
       FIG. 4  is the internal structure diagram of the electrical receptacle according to the present invention. 
       FIGS. 5 and 6  are the movement diagrams showing that the electrical receptacles are controlled by the switch members according to the present invention. 
       FIGS. 7 and 8  are the movement and structure diagrams according to the present invention. 
       FIGS. 9 and 10  are the movement and structure diagrams according to the present invention. 
       FIG. 11  is a diagram showing that the switch member of the electrical receptacle is connected with the locking apparatus according to the present invention. 
       FIG. 12  is a diagram showing that the switch member of the electrical receptacle is connected with the locking apparatus according to the present invention. 
       FIG. 13  is a diagram showing that the electrical receptacle has a safety cover according to the present invention. 
       FIGS. 14(   a ), ( b ) and ( c ) are diagrams showing that the electrical receptacles are connected with different pins of plugs according to the present invention. 
       FIG. 15  is an application diagram of the electrical receptacle according to the present invention. 
   

   DETAILED DESCRIPTION 
   Please refer to  FIGS. 3 and 4 . They illustrate the components of the electrical receptacles in embodiments of the present invention. The electrical receptacle  30  comprises a substance  32  with a plurality of holes  322 , a plurality of conductivity slices  34 , a movable latch  36  movably installed in the substance  32 , and a switch member  38  installed on the substance  32 . 
   The substance  32  is able to be composed of many kinds of components but essentially comprises the conductivity slices  34  and the latch  36 . The shape of the holes  322  installed on the substance  32  varies according to the specification of the plugs  40  in each country or region. The shape of the holes  322  in the present invention corresponds with the plug  40  having two flat pins  42 . The number of conductivity slices  34  in the substance  32  is equal to the number of pins  42  of the plug  40 . The pins  42  are inserted into the holes  322  for transferring electricity to the electrical product (not shown). 
   The latch  36  can be moved through the switch member  38 . In the diagram, the latch  36  is indirectly moved through the switch member  38  by a linked stick  50 . However, the latch  36  could also be connected with the switch member  38  directly and the linked stick  50  is not necessary. 
   The switch member  38  is connected with the linked stick  50  through a handle  382  and a corresponding trench  52 . More specifically, the latch  36  is connected with the linked stick  50  through a short column  362  and an inclined trench  54 . For this reason the latch  36  can move synchronously with the switch member  38  through the linked stick  50 . 
   The switch member  38  can also be controlled by force. As the illustration shows, the switch member  38  is a button installed on the substance  32 . The switch member  38  is rotated into different angles by force for moving the latch  36 . 
     FIGS. 5 and 6  illustrate the electrical receptacle  30  without conductivity slices  34 , where the switch member  38  is in different positions. In  FIG. 5 , the switch member  38  installed on the substance  32  is rotated by force into different positions and the latch  36  is changed to an unlocking position (shown in  FIG. 5 ) or a locking position (shown in  FIG. 6 ) through the linked stick  50 . The unlocking position is the condition that the latch  36  is unable to limit the pins  42  of the plug  40  to plug or to unplug. The locking position is the condition that the latch  36  is able to limit the pins  42  of the plug  40  to plug or unplug. 
   Furthermore, the latch  36  prevents the pins  42  of the plug  40 , especially the small holes  422  of the pins  42 , from changing into the locking position or the unlocking position, especially the small holes  422  of the pins  42 . The pins  42  of the plug  40  are inserted into the holes  322  of the substance  32  firstly and the small holes  422  of the pins  42  are held by the latch  36  for the locking position, and are not held by the latch  36  for the unlocking position. 
   In the above paragraph, the plug  40  is described as being inserted into the substance  32  already. In reality, the latch  36  could already be in the locking position for limiting the entrance of the pins  42  of the plug  40  through the holes  322 . The order of the holes  322  of the substance  32  is shown in the illustration, which shows the linked stick  50  and at least one latch  36  are moved synchronously through an inclined plane or other prior arts according to the corresponding position of the linked stick  50  and the latch  36 . The latch  36  and the linked stick  50  could also have different paths. 
     FIGS. 7 and 8  show the other arrangement of the linked stick  50  and the latch  36 . As in the illustration, the linked stick  50  and the latch  36  could be a monolithically-formed structure where the path of the pins  42  is limited through the latch  36 . Accordingly, the latch  36  is moved synchronously with the linked stick  50 , while the linked stick  50  is driven by the switch member  38 . 
     FIGS. 9 and 10  illustrate the electrical receptacle  30  combined with a locking apparatus  60  in the present invention. The electrical receptacle  30  is locked to the linked stick  50  through the locking apparatus  60  meaning the switch member  38  cannot move the latch  36  anymore. The locking apparatus  60  could be any prior combination locks, key locks or button locks. The locking apparatus  60  can be installed in a position for locking the linked stick  50  when the latch  36  is stuck by the linked stick  50  into the locking or unlocking position, and the switch member  38  is unable to be moved by the linked stick  50 . 
   There are many ways that the locking apparatus  60  can lock the switch member  38 . The locking apparatus  60  can be combined with the switch member  38  directly; the locking apparatus  60  and the switch member  38  could even be a monolithically-formed structure. 
     FIG. 11  illustrates the electrical receptacle  30  having a substance of the locking apparatus  60  connected with the switch member  38 . The locking apparatus  60  in the illustration is a lock that is opened by an identified key. The switch member  38  has a keyhole  62  for the identified key. The key is inserted into the keyhole  62  to release the movement limitation of the switch member  38 , allowing the switch member  38  to change the position of the latch  36 . Because this locking apparatus is well known to those skilled in the art, the process of locking or unlocking is omitted here. 
     FIG. 12  shows a switch member  38  connected with an locking apparatus  60  according to the present invention. The key K is inserted into the keyhole  62  and operates the switch member  38  to move the latch  36 . And, the switch member  38  is not only a rotating switch in the above invention but also a switching button or any similar member. 
   From the above descriptions, the present invention is an electrical receptacle  30  having a safety mechanism to limit the pins  42  of plug  40  to be inserted or taken off. This is not limited to the plug  40 , however; the electrical receptacle  30  could be inserted by any other plug having a different shape. This is illustrated in  FIG. 14 , which shows the electrical receptacle  30  covered by a safety cover  70  of pins  72 , and the holes  322  concealed to avoid the electrical receptacle  30  being used. 
   The pins  42  are clipped by the conductivity slice  34  and are stuck by the latch  36  when the pins  42  are inserted into the electrical receptacle  30 . As in  FIG. 4 , because the conductivity slice  34  limits the latch  36  to stick the pin  42 , the conductivity slice  34  has an opening  342  for the latch  36 . 
   In addition, if the conductivity slice  34  does not limit the latch  36  to stick the pin  42 , the conductivity slice  34  need not have any opening as shown in  FIG. 14(   a ). 
   The latch  36  will not only be stopped by the opening  422  of the pin  42  when the latch  36  is stuck with the pin  42  of the plug  40 . The gap  424  of the pin  42  in  FIG. 14(   b ) and the opposite surface  426  of the pin  42  in  FIG. 14(   c ) are also able to stick the latch  36 . 
   Therefore the present invention is not only suitable for a fixed electrical receptacle  30 , but also for a receptacle with an extended line  80  as shown in  FIG. 15 , or similar products. 
   As illustrated in  FIG. 15 , the present invention is used in another kind of product. The fixed electrical receptacle  30  having a safety mechanism limits the receptacle with extended line  80  to be taken off by the plug  82 , which is inserted into the receptacle  30 . The receptacle with extended line  80  is able to limit the external plug  90  from being taken off or inserted, by its safety mechanism. 
   Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.