Patent Publication Number: US-2006014406-A1

Title: Safety system for current outlets, fluorescent tube, sockets, lamp holders and the like

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The instant invention relates to a safety system for current outlets, fluorescent tube sockets, lamp holders and the like.  
      2. Prior Art  
      Several systems for protecting against electric current shocks received due to lack of care, inexpertness or lack of knowledge are already known.  
      Already known are outlets provided with snap fit covers at the inlet of plug sockets in which pins may only be introduced after removing such covers.  
      Embodiments wherein covers may de displaced to the sides for clearing the inlets to plug sockets are also known.  
      Among the disadvantages related to the first mentioned solution, covers should be withdrawn in order to effect the electrical connection and such covers should have a certain strength in order to make the withdrawal action difficult in order to guarantee the protection sought.  
      On their part, sliding covers may be actuated by a lug which is ease to remove, even by children.  
      A third solution comprises two parallel plates provided with the openings required to carry out the connection, but one of said plates is engaged to a resilient means causing displacement thereof, such that the openings in the plate do not mate with openings on the other plate.  
      In this way, alignment between inlet holes and electric installation poles is interrupted, such that the openings be dissimulated not to call the attention of unskilled persons.  
      In order to connect a device, plug pins are introduced into the outer plate openings and such plate is displaced to one side counteracting the resistance of the resilient means until holes on both plates are aligned and allow the introduction of pins, thus effecting the connection.  
      Other safety means is obtained by replacing round pins for flat pins which, upon reducing the access surface inside the socket, limits the amount of objects which may be introduced inside the plug sockets or housings.  
      In all mentioned cases, when plug pins are introduced, these contact the corresponding housings which in turn are connected to the power supply.  
      In the instant invention, any element introduced into the housing of the outlet will not close the circuit since said housings are not connected to the power supply.  
      In fact, plug pins or any other conductor member will be able to close the electric circuit provided both are introduced in the respective housing simultaneously, since only in this way they may actuate on the blocking arms of a device provided with the means required to close the circuit.  
      The invention allows using almost all matrixes in use at present, with small modifications for adapting them to the new shapes and characteristics.  
      The system of the invention includes a device which may be placed in any kind of outlet, fluorescent tube socket, lamp holder or the like to adapt existing devices in order that they may take advantage of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view showing an outlet cover wherein the openings for the pins to pass and the upper portion of the device container are depicted.  
       FIG. 2  is a schematic perspective view of an outlet body without the cover thus allowing viewing the interior thereof.  
       FIG. 3  is an schematic plan view of an outlet body, showing the pin housings, the lower portion of the device container and the new location of the contacts.  
       FIG. 4  is a schematic plan view of an outlet body, similar to that of  FIG. 3 , but showing only the electrical circuit.  
       FIG. 5  is a schematic partial view of a housing modified for permitting actuation of the device.  
       FIG. 6  is a schematic perspective view of a pyramidal device wherein blocking arms, contacts intercrossing and the resilient means are shown. 
    
    
     REFERENCES  
      In the accompanying drawings the same reference numerals indicate the same or corresponding parts, as follows: 
       1 —Housing      2 —pin      3 —device      4 —cover      5 —upper portion of a container      6 —body      7 —lower portion of the container      8 —blocking arm      9 —resilient means      10 —rear portion      11 —front portion      12 —device grooving or knurling      13 —grooving or knurling of the lower portion of the container      14 —terminal      15 —cable      16 —terminal point.    

     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)  
      Basically, the instant invention provides a safety system for current outlets comprised by a device projecting two blocking arms mating with the housings provided for the pins.  
      Such device also provides a resilient means at the lower base and at least one of its faces with a grooving or knurling.  
      At the opposite base of said device there are corresponding projections engaging contact points connected to the power supply.  
     Operation  
      Once established the different components of the present embodiment of the invention, a functional and operational description of the parts and results afforded is given below.  
      In order to obtain a safety system for current outlets, fluorescent tube sockets, lamps holders and the like, some of such conventional elements is selected in order to proceed with its adaptation.  
      In the following description reference is made to a current outlet, merely for a better understanding of the invention without being limited to this embodiment.  
      In order to adapt a conventional outlet, a strip of insulating material coating housings  1  developed to contain pins  2  of a conventional plug is removed.  
      To fit device  3  such that it is sufficiently fixed once the outlet is assembled, at the cover  4  thereof the upper portion of a container  5  is formed, while in body  6  of said outlet the lower portion of a container  7  is formed.  
      Taking into account that the space within an outlet limited between housings  1  for pins  2  has variable shape according to the manufacturing practices, the applicant has studied such variations to limit the plan of the housing of the device  3 .  
      Therefore, the inventor has determined that such plan is feasible in a triangular or quadrangular shape, thus having the device  3  container a plan having a triangle, square or rectangle shape.  
      Any of such forms for device  3  are appropriate in the invention and, in the annexed figures, a rectangular plan is shown in  FIG. 3  and a device ( 3 ) with triangular bases is shown in  FIG. 6 .  
      The lower portion of container  7  is higher than the upper portion of container  5 , thus allowing accommodation of more than a half of the device  3  therein.  
      Coinciding with the location of housings  1  for pins  2 , such device  3  projects respective blocking arms  8  made of rigid, resistant material, at least its outer layer being an insulating layer.  
      At the lower base of the device  3 , there is a resilient means  9  acting expansively to separate said lower base from the bottom of the container.  
      In turn, at the upper base of said device  3 , there are corresponding contacts made of conductive material, each of which is located such that a rear portion  10  encompasses at least partially the side of device  3  and a front portion  11  projecting towards the front.  
      When a plug is introduced into the outlet, pins  2  will contact the blocking arms  8  biasing them downwardly, thus carrying in this way the device  3  engaged thereto.  
      In such case, resilient means  9  will begin compression accumulating energy which allows biasing device  3  upwardly when the plug is removed.  
      When a single pin  2  or any other object of conductive material is introduced, the corresponding blocking arm  8  will be interposed in this path, thus preventing the passage.  
      If someone introduces the object or the pin exerting increased pressure trying to force introduction, device  3  will be unbalanced and blocked against the container.  
      In order to improve gripping between device  3  and the container in cases such as that already described, at least on one of the faces of device  3  a grooving or knurling  12  will be provided, and on at least the face in front of the lower portion of the container  7  grooving or knurling will be also provided, mating with the former one.  
      If the object introduced has such a size that overcomes the action of the blocking arm  8 , any point of housing  1  contacted will not be subjected to any consequence since none of the housings is connected to electric current.  
      In fact, originally, the conventional outlet has a housing  1  to ground and the two remaining housings are connected to any of the poles, negative or positive, of the power supply.  
      Therefore, if a conductive object were introduced into housing  1  of a conventional outlet, the circuit would close and the person involved would receive a discharge.  
      In the embodiment disclosed, housings  1  are merely receptors for pins  2  of the plug, since none of them is connected to the power supply.  
      For closing the circuit, pins  2  should bias the blocking arms  8  downwards, thus compressing the resilient means  9  and lowering device  3 .  
      Upon lowering said device  3 , front portions  11  of the contacts are connected to terminals  14  fed from the power supply and rear portions  10  of said contacts will engage the conductive portion of housings  1  closing the circuit and allowing current passage from the power supply, through terminals  14  and of front  11  and rear  10  portions of the contacts, thus reaching the metal (or conductive) portion of respective housings  1  and, from there, to pins  2  of the plug.  
      In the preferred embodiment disclosed, front portions  11  are intercrossed such that each of pins  2  of a plug, enables current passage from housing  1  which corresponds to the other pin  2 .  
      In a preferred embodiment, device  3  has a widening at the upper end, such that rear portions ( 10 ) of the contacts project from the perimeter. In this embodiment, the rear portions  10  have a side the lower edge of which coincides with the body of device  3  while the upper edge is separated.  
      As described, when device  3  is lowered, rear portions  10  work as a wedge biasing the metal portion of housings  1  against pins  2  favoring retention of the pins.  
      Upon removing pins  2  from the plug, the side angle facilitates sliding of device  3  biased upwards by the resilient means  9 .  
      In turn, the front portion  11  of the contacts engages terminals  14  tightly, thus pressing and forcing the position of the binding screws.  
      When pins  2  are removed, the resilient means  9  pushes device  3  upwards disengaging the contacts and making that terminals  14  return to their initial position due to elastic memory.  
      As may be seen in  FIGS. 3 and 4 , cable  15  connected to the power supply is bifurcated at its two poles such that each of the poles is connected to a terminal point  16  which is electrically connected to one of the terminals  14 .  
      As seen in the mentioned figures, each terminal point  16  is displaced as compared to the location it would adopt in a conventional outlet, where it would be connected to one of the housings  1  and, for this reason, housings  1  of the system disclosed, will be only subjected to voltage when the front portions  11  of the contacts close the circuit engaging terminals  14 .  
      In an alternative embodiment, said front portions  11  have a region in a plane parallel to the upper base of the device  3  and a final region located downwardly, while terminals  14  are within an insulating material housing such that their upper end is below the upper level of such housing.  
      In this embodiment, when pins  2  are introduced for lowering device  3 , displacement of the latter downwards causes the ends of the final region of front portions  11  to be introduced into said housing and, within the housing, they contact terminals  14  for closing the circuit.  
      In a further alternative embodiment, under cover  4 , there are corresponding laminar bodies preventing access of a body through the inlets of housings  1 .  
      When an object is introduced into any housing  1 , said laminar body intercepts his way.  
      The upper face of said laminar body faces the object or pin  2  but, since said face has a side recess, said object or pin  2  will be able to slide displacing the pin, this displacement being transmitted to the laminar body blocking passage through the other housing  1 .  
      This drift caused by the remaining laminar body puts the recess of the upper face out of alignment and, therefore, the object or pin  2  will abut against a planar portion of said laminar body, which will prevent its passage.  
      Upon removal of the plug, both laminar bodies will return to their original positions due to the action of corresponding springs.  
      In a preferred embodiment, all faces of device  3  are provided with a grooving or knurling  12  and all faces of the container are provided with a grooving or knurling  13 .  
      The invention has been described in connection with one of the constructive possibilities of the invention and with its operation, the scope of the invention being only limited by the appended claims.