Abstract:
A receptacle including a front surface including one or more slots for receiving contact blades; a rear surface including one or more terminals for connecting the contact blades to a power source, the one or more terminals being line terminals and load terminals; a shutter positioned between the front surface and the rear surface of the receptacle, the shutter configured to be misaligned in relation to the one or more slots in order to obstruct a direct path between the contact blades and the one or more terminals, wherein insertion of an object in the one or more slots causes displacement of the shutter; and a shutter lock operatively connected in the receptacle to receive power from the power source connected to the receptacle.

Description:
This application claims priority pursuant to 35 U.S.C. 119(e) from U.S. Provisional Application having Application No. 60/772,169 filed Feb. 10, 2006. 

   TECHNICAL FIELD 
   The present disclosure generally relates to tamper-resistant shutters. In particular, the present disclosure relates to a shutter lock that is operatively connected in the receptacle to receive power from the power source connected to the receptacle. 
   BACKGROUND OF THE RELATED ART 
   In an effort to prevent electrical shock, circuit interrupting devices are designed to interrupt power to various loads, such as household appliances and consumer electrical products. In particular, electrical building codes in many states require that electrical circuits in residential or commercial bathrooms and kitchens be equipped with circuit interrupting devices. Household appliances are typically connected to electrical receptacles having at least a hot terminal and neutral terminal; the terminals are usually implemented as receptacles to which an electrical plug of the household appliance is attached. When an appliance is working properly, the current used by the appliance flows from the hot terminal of the electrical receptacle through the appliance and back to the neutral terminal of the receptacle. When, however, a person uses an appliance in the rain or near a wet surface, an extra path may be created from the appliance through the person and the water to ground. Consequently the amplitude of the current flowing from the receptacle to the household appliance is not be equal to the amplitude of the current flowing from the appliance back to the neutral terminal of the receptacle; that is, part of the current has been diverted through the extra path. Therefore, an imbalance in the current flow is created; this imbalance is typically referred to as a ground fault. 
   There exists a circuit between the receptacle and a power source which provides power to the receptacle. In particular, a hot or phase wire from the power source is connected to a phase terminal of the receptacle and a neutral wire from the power source is connected to a neutral terminal of the receptacle. A circuit interrupting device, such as a ground fault circuit interrupter (GFCI) is placed in the receptacle and is connected to the phase and neutral terminals of the receptacle. Thus, when a household device is plugged into the receptacle the hot or phase wire extends from the power source to the receptacle through the GFCI to the household appliance. Also, a neutral connection extends from the household appliance to the receptacle through the GFCI and onto the power source&#39;s neutral terminal. As such, the GFCI is positioned as part of a circuit comprising the power source, the conductors connecting the power source to the receptacle, conductors connecting the receptacle to the appliance and conductors from the appliance to the receptacle and back to the power source. There is a switching device within the GFCI that—when closed—allows the current in the circuit to flow from the power source through the GFCI to the appliance and from the appliance back to the receptacle through the GFCI and back to the power source. Circuit interrupting devices are designed to detect current imbalances and activate their switching device so as to disconnect power from the receptacle thus disconnecting power from a household device plugged to the receptacle when a ground fault is detected. 
   Presently available circuit interrupting devices, such as the device described in commonly owned U.S. Pat. No. 4,595,894, use a trip device to mechanically break an electrical connection between one or more input and output conductors of the circuit interrupting device. Such devices are resettable after the detection of a ground fault, for example. In particular, a trip device is used to cause the mechanical breaking of the circuit. The trip device includes a solenoid (or trip coil). As a feature to test the trip device and circuitry used to sense faults, a test button is used to initiate a manual test of the GFCI. In addition, a reset button is used to reset the electrical connection between input and output conductors of the GFCI. 
   Electrical receptacles within which are located circuit interrupting devices (such as GFCIs) have a line side, which is connectable to an electrical power supply, and a load side, which is connectable to one or more loads (e.g., other receptacles). Where a circuit interrupting device includes a user accessible connection, the load side connection and user accessible connection are typically electrically connected to each other. An example of the user accessible connection is a two hole or three hole receptacle used for AC outlets; the connection is implemented as receptacle terminal in which a plug can be connected providing power to an electrical household device, for example. Wires from the power source are connected to the line side of the GFCI receptacle and wires from one or more loads (e.g., other receptacles) are connected to the load side of the GFCI receptacle. Instances, however, may occur where the circuit interrupting device is improperly connected to the external wires so that the load wires are connected to the line side connection and the line wires are connected to the load side connection; this is known as reverse wiring. In the event the circuit interrupting device is reverse wired, fault protection to the user accessible load connection may be eliminated, even if fault protection to the load side connection remains. Thus, there is a need for electrical receptacles that are capable of detecting when reverse wiring has occurred. 
   Moreover, in an effort to limit the exposure of children to electrical shock, the National Electrical Code (NEC) requires that in buildings where the predominant function of such buildings is to provide shelter for children (e.g., schools, nurseries, daycare facilities, hospitals, residential housing), tamper-resistant electrical receptacles and ground fault circuit interrupters (GFCI) should be designed within an electrical distribution system throughout such residential or commercial buildings. In particular, since a large percentage of electrical receptacles used in residential buildings are installed near the floor, a person, such as a young child or infant, for example, can insert small elongated articles into the cover apertures of the electrical receptacle. More particularly, if the child inserts an object made of conductive material including but not limited to a metal article, electrical shock may result. Another possibility is where an infant or a young child places his or her mouth over an electrical receptacle. Accordingly, a burn or shock may result when the child&#39;s wet mouth makes contact with one of the terminals; this is because a path is caused to exist from the hot receptacle terminal through the child to ground creating a ground fault. Ground fault circuit interrupters, however, only disconnect the power supplied to the circuit after a child has made contact with a conductor. Thus, without a tamper resistant electrical receptacle, a child may still experience an electrical shock. 
   Commonly owned, co-pending patent application Ser. No. 10/690,776, filed Oct. 22, 2003 which is incorporated herein in its entirety by reference, describes a family of resettable circuit interrupting devices (e.g., GFCI receptacles) capable of preventing electric power from being accessible to users of such devices when these devices are reverse wired. Each device has a reset lockout system that prevents the device from being reset when the device is not operating properly. When the device is not reset and if such device is reverse wired, no power is available to any user accessible receptacles and/or plugs located on the face of the devices. The device is preferably shipped in a trip condition, where no electrical connection exists between line and load terminals and no electrical connection exists between load and face terminals. Thus, in the trip condition the three terminals are electrically isolated from each other. If the device is wired in reverse, the device cannot be reset. 
   However, presently there are no devices within the family of resettable circuit interrupting devices having reverse wiring protection (e.g., such as a shutter lock) that includes a tamper-proof feature. Therefore, there is a need for a simple, effective, efficient, low-cost electrical receptacle that is tamper-proof and provides protection from reverse wiring. 
   SUMMARY 
   The present disclosure is directed to a receptacle coupled to a tamper-resistant device comprising shutters. In a preferred exemplary embodiment, the shutters prevent access to the face terminals if an object is incorrectly inserted into the receptacle. In addition, the present disclosure can be incorporated into a GFCI which comprises a circuit interrupting circuit. Furthermore, the shutters of the present disclosure may also operate in conjunction with the circuit interrupting portion of the receptacle to either permit or prevent access to the face terminals based on the state of the circuit interrupting device. 
   In one aspect of the present disclosure a receptacle is presented. The receptacle includes a front surface including one or more slots for receiving contact blades; a rear surface including one or more terminals for connecting the contact blades to a power source, the one or more terminals being line terminals and load terminals; a shutter positioned between the front surface and the rear surface of the receptacle, the shutter configured to be misaligned in relation to the one or more slots in order to obstruct a direct path between the contact blades and the one or more terminals, wherein insertion of an object in the one or more slots causes displacement of the shutter; and a shutter lock operatively connected in the receptacle to receive power from the power source connected to the receptacle. 
   In another aspect of the present disclosure a different receptacle is presented. The receptacle includes a front surface and a rear surface for connecting a compatible object to a power source; a shutter positioned between the front surface and the rear surface, the shutter configured to prevent a non-compatible object from being inserted into one or more slots of the front surface of the receptacle; and a shutter lock operatively connected in the receptacle to receive power from a power source connected to the receptacle preventing displacement of said shutter when the receptacle is reverse-wired. 
   In another aspect of the present disclosure a receptacle only having a shutter is presented. The receptacle includes a front surface and a rear surface for connecting a compatible object to a power source; and a shutter positioned between the front surface and the rear surface, the shutter configured to prevent a non-compatible object from being inserted into one or more slots of the front surface of the receptacle. 
   In another aspect of the present disclosure a method for combining a tamper-resistant device and a reverse-wiring circuit within a receptacle is presented. The method for combining a tamper-resistant device and a shutter lock within a receptacle, the receptacle having a front surface including one or more slots for receiving contact blades and a rear surface including one or more terminals for connecting the contact blades to a power source, the one or more terminals being line terminals and load terminals, the tamper-resistant device positioned between the front surface and the rear surface of the receptacle and configured to be misaligned in relation to the one or more slots in order to obstruct a direct path between the contact blades and the one or more terminals, wherein insertion of an object in the one or more slots causes displacement of the tamper-resistant device, the method including applying power from the power source to the line terminals of the receptacle in order to release a pivoting locking bar; and inserting the contact blades to move the tamper-resistant device for allowing an electrical connection between the contact blades and the one or more terminals of the receptacle. 
   In another aspect of the present disclosure a method for combining a tamper-resistant device and a reverse-wiring circuit within a receptacle is presented. The method for combining a tamper-resistant device and a shutter lock within a receptacle, the receptacle having a front surface and a rear surface for connecting a compatible object to a power source, the tamper-resistant device positioned between the front surface and the rear surface and configured to prevent a non-compatible object from being inserted into one or more slots of the front surface of the receptacle, the shutter lock operatively connected in the receptacle to receive power from a power source connected to the receptacle, the method including releasing a pivoting locking bar; and inserting the contact blades to move the tamper-resistant device for allowing an electrical connection between the contact blades and the one or more terminals of the receptacle. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the exemplary embodiment of the present disclosure and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numbers indicate like features and wherein: 
       FIGS. 1-6  show the sequence of operation when a circuit interrupting device in accordance with the present disclosure is reset from a tripped state; 
       FIGS. 7-10  show the sequence of operation when a circuit interrupting device in accordance with the present disclosure is tripped while in a reset state; 
       FIG. 11  illustrates a front view of the electrical receptacle in accordance with an embodiment of the present disclosure; 
       FIG. 12  displays a cross-sectional view of  FIG. 11  taken along Section line A-A where the cut extends through receptacle when the pivoting locking rod is in the locked position; 
       FIG. 13  shows a cross-sectional view of  FIG. 11  taken along Section line A-A where the cut extends through receptacle when the pivoting locking rod is in the unlocked position; 
       FIG. 14  displays a perspective view of the electrical receptacle of an embodiment of the present disclosure with the cover removed; 
       FIG. 14A  is a view of the device in  FIG. 14  in accordance with another embodiment of the electrical receptacle where a solenoid is coupled to the locking rod instead of a mechanical arm; 
       FIG. 15  illustrates a front view of the electrical receptacle of  FIG. 11  having cut line B-B; 
       FIG. 16  illustrates a cross-sectional view of  FIG. 15  taken along Section line B-B where the cut extends through receptacle when the pivoting locking rod is in the locked position; 
       FIG. 17  illustrates a front view of the electrical receptacle of  FIG. 11  having cut line C-C; 
       FIG. 18  displays a cross-sectional view of  FIG. 17  taken along Section line C-C where the cut extends through receptacle when the pivoting locking rod is in the unlocked position; 
       FIG. 19  displays a cross-sectional view of  FIG. 17  taken along Section line C-C where the cut extends through the cover without cutting shutter when the pivoting locking rod is in the locked position; 
       FIG. 19A  is a view of the device in  FIG. 19  in accordance with another embodiment of the device where an additional ramp element is added to decrease the angle on the shutter such that the shutter is supported on an angled platform as opposed to a flat platform; 
       FIG. 20  shows a cross-sectional view of  FIG. 17  taken along Section line C-C where the cut extends through the cover without cutting shutter when the pivoting locking rod is in the locked position and wherein an electrical prong (not shown) is inserted causing the shutter to tilt in an intermediate position; 
       FIG. 21  displays a cross-sectional view of  FIG. 17  taken along Section line C-C where the cut extends through the cover without cutting shutter when the pivoting locking rod is in the locked position and wherein an electrical prong (not shown) is inserted causing the shutter to tilt fully; and 
       FIG. 22  shows the underside view of  FIG. 14  displaying how the pivoting locking rods fit into their respective slots. 
   

   DETAILED DESCRIPTION 
   The following description is presented to enable one of ordinary skill in the art to make and use the disclosure and is provided in the context of a patent application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. Thus, the present disclosure is not intended to be limited to the embodiments shown but is to be accorded the broadest scope consistent with the principles and features described herein. 
   I. GFCI Operation 
   Referring to  FIGS. 1-6 , there is shown a sequence of how the GFCI is reset from a tripped condition. When the GFCI device is in a tripped condition, the line, load and face terminals are electrically isolated from each other because the movable bridges are not engaged to any of the terminals. 
   Referring to  FIG. 1  there is shown the positioning of a reset button  20 , reset pin  76 , reset pin lower portion  76 A and disk  76 B when the device is in the tripped condition. In the tripped condition, the lifter  78  positioned below the movable bridges (not shown) does not engage the movable bridges. Reset button  20  is in its fully up position. Latch  84  and lifter  78  are such that the openings of the latch  84  and the lifter  78  are misaligned not allowing disk  76 B to go through the openings. Furthermore, a portion of lifter  78  is positioned directly above test arm  90  but does not engage test arm  90 . One side of the lifter  78  is positioned adjacent a bobbin  82 . A portion of the bobbin  82  is mounted on a printed circuit board  38 . 
   In  FIG. 2 , to initiate the resetting of the GFCI device, reset button  20  is depressed (in the direction shown by  94 A) causing flange  76 B to interfere with latch plate  84  which causes lifter  78  to press down on test arm  90  of. As a result, test arm  90  makes contact with test pin (not shown). One side of the lifter  78  is positioned adjacent a bobbin  82 . A portion of the bobbin  82  is mounted on a printed circuit board  38 . 
   In  FIG. 3 , when test arm  90  makes contact with the test pin, a sensing circuit (not shown) is triggered, thus energizing the coil causing plunger  80  to be momentarily pulled into the bobbin  82  engaging latch plate  84  and more specifically pushing latch plate  84  in the direction shown by arrow  81 . 
   In  FIG. 4 , the latch plate  84 , when pushed by plunger  80 , slides along lifter  78  (in the direction shown by arrow  81 ) so as to align its opening with the lifter opening allowing flange  76 B and part of lower reset pin portion  76 A to extend through the openings  84 B,  78 A. 
   In  FIG. 5 , the latch plate  84  then recoils back (in the direction shown by arrow  81 A) and upon release of the reset button  20 , test arm  90  also springs back disengaging from contact with the test pin. 
   In  FIG. 6 , the recoiling of the latch plate  84  causes the opening  84 B (shown in  FIG. 4 ) to once again be misaligned with opening  74 A (shown in  FIG. 4 ) thus trapping flange  76 B underneath the lifter  78  and latch plate  84 . When reset button is released the biasing of the reset pin  76  in concert with the trapped flange  76 B raise the lifter  78  and latch plate  84  causing the lifter  78  (located underneath the movable bridges) to engage the movable bridges. In particular, the connecting portions of the movable bridges are bent resulting in the line terminals, load terminals and face terminals being electrically connected to each other. The GFCI is now in the reset mode meaning that the electrical contacts of the line, load and face terminals are all electrically connected to each other allowing power from the line terminal to be provided to the load and face terminals. The GFCI remains in the reset mode until the sensing circuit detects a fault or the GFCI is tripped purposely by depressing the test button  22  (discussed with reference to  FIGS. 7-10 ). 
   When the sensing circuit detects a condition such as a ground fault for a GFCI or other conditions (e.g., arc fault, immersion detection fault, appliance leakage fault, equipment leakage fault), the sensing circuit energizes the coil causing the plunger  80  to engage the latch  84  resulting in the latch opening  84 B being aligned with the lifter opening  78 A allowing the lower portion of the reset pin  76 A and the disk  76 B to escape from underneath the lifter  78  causing the lifter  78  to disengage from the movable bridges which, due to their biasing, move away from the face terminals contacts and load terminal contacts. As a result, the line, load and face terminals are electrically isolated from each other and thus the GFCI device is in a tripped state or condition. 
   The GFCI device of an exemplary embodiment of the present disclosure can also enter the tripped state by pressing the test button  22 . In  FIGS. 7-10 , there is illustrated a sequence of operation showing how the device can be tripped using the test button  22 . 
   Similar elements described with reference to  FIGS. 1-6  will not be described with reference to  FIGS. 7-10 . 
   In  FIG. 7 , while the device is in the reset mode, test button  22  is depressed. Test button  22  has test button pin portion  22 A and cam end portion  22 B connected thereto and is mechanically biased upward in the direction shown by arrow  94 . The cam end portion  22 B is preferably conically shaped so that when it engages with the hooked end  84 E of latch plate  84  a cam action occurs due to the angle of the end portion of the test button pin  22 A. 
   In  FIG. 8 , the cam action is the movement of latch plate  84  in the direction shown by arrow  81  as test button  22  is pushed down (direction shown by arrow  94 A) causing latch plate opening  84 B to be aligned with lifter opening  78 A. 
   In  FIG. 9 , the alignment of the openings ( 78 A,  84 B) allows the lower portion of the reset pin  76 A and the disk  76 B to escape from underneath the lifter  78  causing the lifter  78  to disengage from the movable bridges which, due to their biasing, move away from the face terminals contacts and load terminal contacts. The test button  20  is now in a fully up position. As a result, the line, load and face terminals are electrically isolated from each other and thus the GFCI device is in a tripped state or condition (see  FIG. 1 ). 
   In  FIG. 10 , the test button  22  is released allowing its bias to move it upward (direction shown by arrow  94 ) and disengage from the hook portion  84 E of latch plate  84 . The latch plate  84  recoils in the direction shown by arrow  81 A thus causing the opening in the latch plate  84  to be misaligned with the opening of the lifter  78 . The device is now in the tripped position. It should be noted that once the device of an exemplary embodiment of the present disclosure is in a tripped position, depressing the test button does not activate any function because at this point the latch  84  cannot be engaged by the angled end of the test button  22 . The test button  22  performs the trip function after the device has been reset. 
   The GFCI device of the present exemplary embodiment of the disclosure, once in the tripped position, is not permitted to be reset (by pushing the reset button) if the circuit interrupting portion is non-operational; that is if any one or more of the components of the circuit interrupting portion is not operating properly, the device cannot be reset. Further, if the sensing circuit is not operating properly, the device can not be reset. The reset lockout system of the present exemplary embodiment of the disclosure can be implemented in an affirmative manner where one or more components specifically designed for a reset lockout function are arranged so as to prevent the device from being reset if the circuit interrupting portion or if the sensing circuit are not operating properly. The reset lockout system can also be implemented in a passive manner where the device does not enter the reset mode if any one or more of the components of the sensing circuit or if any one or more of the components of the circuit interrupting portion is not operating properly; this passive reset lockout approach is implemented in the present exemplary embodiment of the disclosure. 
   It should be noted that the circuit interrupting device of the present exemplary embodiment of the disclosure may have a trip portion that operates independently of the circuit interrupting portion so that in the event the circuit interrupting portion becomes non-operational the device can still be tripped. Preferably, the trip portion is manually activated and uses mechanical components to break one or more conductive paths. However, the trip portion may use electrical circuitry and/or electro-mechanical components to break either the phase or neutral conductive path or both paths. Additionally, the trip portion may use any suitable means to break one or more of the conductive paths. 
   II. Tamper Resistant Shutter with Reverse-Wiring Protection Circuit 
   In addition to tamper resistant shutters providing child safety protection to a receptacle, the tamper resistant shutter of the present exemplary embodiment provides a second function—not allowing the device to be used when the device is tripped. On initial shipment, the receptacle may be shipped in the tripped state in order to facilitate checking for reverse wiring (e.g., via a shutter lock that is operatively connected in the receptacle to receive power from the power source connected to the receptacle). In particular, a pivoting “locking bar” may be positioned such that, when the GFCI is in the tripped state, the bar blocks the movement of the tamper resistant shutters; the electrical receptacle is thus in a locked position. 
   In this locked position, even if an electrical plug having prongs were properly inserted into the apertures of the receptacle&#39;s cover, these prongs would be prevented from making contact with the Phase and Neutral contacts of the receptacle, i.e., the prongs would be blocked by the shutters. When a receptacle configured in accordance with the preferred exemplary embodiment of the present disclosure is properly installed or wired, the receptacle is reset with the use of a lifter that closes the contacts connecting the line terminals of the receptacle to the load and face terminals of the receptacle. 
   Specifically, the upward motion of the lifter can also be used to force a mechanical arm, which is connected to the center of the pivoting locking rod, to also move upward. This upward motion of the mechanical arm causes the pivoting locking bar to pivot downward out of each slot in the tamper resistant shutters. Specifically, the center of the locking rod may sit between two fulcrums such that when the center of the locking rod is pushed upwards, the two ends of the locking rod pivot downwards. As a result, the two ends of the locking bar move out of a slot in each of the tamper resistant shutters. In the preferred exemplary embodiment there is a tamper resistant shutter for each outlet. In a dual receptacle, there is one shutter for the top outlet and one for the bottom outlet. However, the present disclosure is not limited to a two shutter arrangement. Whether the receptacle has one or more shutters, the disclosure requires a locking bar that is released when power is applied to the line side of the receptacle. When the two ends of the locking bar are clear from the two shutters, the shutters are free to move laterally if an electrical plug having prongs is properly inserted into the outlet. The end result is that the pivoting locking bar does not block the movement of the tamper resistant shutters and the receptacle is placed in an unlocked position allowing a user to insert a plug with prongs in the entry ports of the electrical receptacle when the prongs make electrical contact with the face terminals. 
     FIGS. 11-14A  illustrate the operation of the electrical receptacle having a GFCI and tamper resistant shutters disposed therein in accordance with the illustrated preferred exemplary embodiment of the present disclosure. Turning now to  FIG. 11 , the electrical receptacle  100  has a face or cover portion  120 . The face portion  120  has entry ports  110   a ,  110   b , and  112   a  for receiving normal or polarized prongs of a male plug of the type normally found at the end of an electrical appliance (e.g., a lamp) or appliance cord set (not shown), as well as ground-prong-receiving openings  114  to accommodate a three-wire plug. The receptacle also includes a mounting strap  122  used to fasten the receptacle to a junction box. Face or cover portion  120  is mounted on housing  108 . Optionally, the face portion may be an integral part of the housing. 
   A test button  118  may extend through opening  119  in the face portion  120 . The test button  118  may be used to activate a test operation, that tests the operation of the circuit interrupting device disposed in the housing  108 . Optionally, the test operation may test for any desired condition. The circuit interrupting portion, to be described in more detail below, is used to break electrical continuity in one or more conductive paths between the line and load side of the device. A reset button  116  which may form a part of the reset portion may extend through opening  117  in the face portion  120 . The reset button may be used to activate a reset operation, which reestablishes electrical continuity in the open conductive paths. 
     FIG. 12  represents a cross-section view of  FIG. 11  taken along Section line A-A where the cut extends through receptacle  100  wherein the pivoting locking rod comprising sections  128 ,  130  is in the locked position. Section line A-A extends through receptacle  100  across entry ports  112   a  and  112   b . As shown in  FIG. 12 , the face or cover portion  120  has entry ports  112   a  and  112   b  aligned with tamper resistant shutters  124  and  126 , respectively. 
   During normal operation, when a pair of normal or polarized prongs of a male plug of the type normally found at the end of an appliance cord set (not shown) are inserted in entry port  112   a , shutter  124  shifts to enable the prong to pass through aperture  146   a  making contact with receptacle terminals  142 , wherein entry port  112   a  aligns with shutter  124 . Similarly, the pair of prongs may be inserted in entry port  112   b , such that shutter  126  shifts to enable the prongs to pass through aperture  146   b  (shown in  FIG. 13 ) making contact with receptacle (or face) terminal  144 . 
   Normal operation, however, is hindered in the locked position where the ends of the pivoting locking bar sections  128 ,  130  are positioned in slots  148   a  and  148   b  of tamper resistant shutters  124  and  126 , respectively. It is in this locking position that receptacle  100  may be shipped to ensure that reverse wiring is prevented or corrected during installation of the unit. 
   The GFCI receptacle is in the tripped condition as contact  140  is disconnected (or is not making contact with) contact  138 . In the present exemplary embodiment, contact  138  may be mounted on movable bridge  134  (shown in  FIG. 13 ) and in contact with a mechanical arm  132 . Contact  140  is mounted on part of the conductive path for one of the load terminals. It is understood that the other contacts for the line, load and face terminals (although not shown in  FIG. 12 ) are positioned in similar fashion with respect to each other such that when the GFCI receptacle is in the tripped condition, the line, load and face terminals are electrically isolated from each other. In addition, housing  108  includes mounting strap  122  located on two opposing sides of receptacle  100 . 
   Responsive to a correctly wired receptacle  100  that is reset, (i.e., reset button is depressed) lifter  136  shifts upward (i.e., in the direction shown by arrow  135 ) making contact with movable bridge  134 . Thus, in operation as shown in  FIG. 13 , if the receptacle  100  is wired correctly, lifter  136  responds to a reset operation in the GFCI, by shifting in the direction shown by arrow  135  and making contact with movable bridge  134 . Accordingly, contact  138  mounted on movable bridge  134  is shifted in the direction shown by arrow  135  to meet contact  140 . When contacts  138  and  140  are engaged, the receptacle  100  is reset. It should be understood that only one set of contacts are shown for ease of explanation; in a typical GFCI two or three sets of contacts mate with each other to reset the device. In this case, as lifter  136  moves in the direction shown by arrow  135  enabling the receptacle  100  to be reset, mechanical arm  132  shifts in the same direction pivoting the sections  128  and  130  of the locking rod. Each respective end of each of the sections  128 ,  130  of the pivoting locking rod pivots downwards (in the direction shown by arrow  137 ) out of in each respective tamper resistant shutter  124 ,  126 . 
   Until receptacle  100  is correctly wired, receptacle  100  remains in the locked position shown in  FIG. 12 . In particular, the mechanical arm  132  remains in this locked position wherein each end of the pivoting locking bar sections  128 ,  30  sits in each respective slot  148   a ,  148   b  of the tamper resistant shutters,  124  and  126 . Effectively, the use of receptacle  100  is disabled until the receptacle  100  is wired correctly and reset. 
     FIG. 14  represents a perspective view of the electrical receptacle  100  (shown in  FIG. 19 ) in accordance with the preferred exemplary embodiment of the present disclosure having the cover removed, wherein the receptacle  100  is in the locked position. As shown mechanical arm  132  is in the locked position, wherein each end of the pivoting locking rod sections  128 ,  130  is held in each respective slot ( 148   a ,  148   b -shown in  FIG. 20 ) of the tamper resistant shutters,  124  and  126 . With the pivoting locking bar sections  128 ,  130  in the position shown, the shutters,  124  and  126 , are prevented from sliding in the direction shown by arrow “D” when a plug is inserted in either set of entry ports. In addition, reset button  116  and test button  118  are shown. 
     FIG. 22  shows the underside view of  FIG. 14 . For ease of illustration shutter  124  is not shown. However, shutter  126  is shown and the manner in which the end of pivoting locking rod section  130  fits into slot  148   b . Also, slots  148   a  and  148   b  also include slots made in the housing structure and not only the shutters; this is shown in the way pivoting locking rod  128  fits into slot  148   a . Also shown are springs  164  that bias the shutters  126  and  126  respectively. 
     FIG. 15  illustrates the same receptacle  100  of  FIG. 11  having section line B-B which extends through the center of entry points  110  and  112 .  FIG. 16  is the corresponding cross-section view of  FIG. 15  taken along Section line B-B where the cut extends through receptacle  100  when the pivoting locking bar  128 ,  130  is in the locked position. As shown tamper resistant shutter  24  includes an aperture  50  that aligns with entry port  110   a  and aperture  145   a  when the shutter is in the unlocked position as shown in  FIG. 17 . 
   In  FIG. 16 , however, spring  164  is biased to keep shutter  124  in the position shown. Shutter  124  shifts in the direction shown by arrow “F” when a pair of prongs inserted in apertures  110   a  and  112   a  overcomes the bias force of spring  164  to make contact with receptacle terminals  142   a  and  142   b  and the electrical receptacle has been reset. Effectively, during installation or at any time when the receptacle  100  is reversed wired and tripped, the receptacle  100  cannot be used by a user due to the pivoting locking rod sections  128 ,  130  and the tamper resistant shutters  124  and  126 . 
     FIG. 18  displays a cross-section view of  FIG. 17  taken along Section line C-C where the cut extends through receptacle  100  when the pivoting locking bar  128 ,  130  is in the unlocked position. Specifically, prongs (not shown) are inserted in entry ports  110   a ,  112   a  overcoming the bias of spring  164  causing said spring to be shifted by the sliding shutter  124  which is caused to slide by the insertion of the prongs. As shown, entry port  110   a , and apertures  150 , and  145   a  align to enable a prong inserted in aperture  110   a  to pass through the tamper resistant shutter  124  at aperture  150  and make contact with receptacle terminal  142   a . In addition, a second prong may simultaneously pass through apertures  112   a  and  146   a  to make contact with receptacle terminal  142   b.    
     FIG. 17  illustrates the same receptacle  100  of  FIG. 11  having cut line C-C.  FIG. 19  displays a cross-section view of  FIG. 18  taken along Section line C-C where the cut extends through the cover  120  without cutting shutter  124  with the pivoting locking rod sections  128 ,  130  in the locked position. Specifically, tamper resistant shutter  124  having projections  158 ,  160 , and  162  sits inside cover  120  under entry ports  110   a  and  112   a . Spring  164  biases tamper resistant shutter  124  into a locked position; shutter  124  is kept from moving out of the locked position by one of the sections (see  FIG. 14 ) of the pivoting locking rod  128 ,  130 . 
     FIG. 19A  is a view of the device in  FIG. 19  in accordance with another exemplary embodiment of the device where an additional ramp element is added to decrease the angle on the shutter  124  such that the shutter  124  is supported on an angled platform as opposed to a flat platform. 
     FIG. 20  shows a cross-section view of  FIG. 18  taken along Section line C-C where the cut extends through the cover  120  without cutting shutter  124  when the pivoting locking rod  128 ,  130  is in the locked position and where an electrical prong (not shown) is inserted causing the shutter  124  to tilt in a direction shown by arrow  125 . When an object probes aperture  110   a  without probing aperture  112   a , tamper resistant shutter  124  tilts in the direction shown by arrow  125  down and does not shift out of the locked position since spring  164  holds shutter  124  in the locked position. 
     FIG. 21  displays a cross-section view of  FIG. 18  taken along Section line C-C where the cut extends through the cover  120  without cutting shutter  124  when the pivoting locking rod  128 ,  130  is in the locked position and wherein an electrical prong (not shown) is inserted causing the shutter  124  to tilt fully. More particularly, when the same object is inserted further through entry port  110   a , the projection  156  on the interior surface of cover  120  catches the projection  162  of shutter  124  such that shutter  124  remains in the locked position. Shutter  124  tilts as described when probed at one point near projection  158  because a part  123   a  of its bottom portion  123  is raised with respect to surface  121  of housing  108 . Part  123   b  of bottom portion  123  is also raised with respect to surface  121 , but to a different extent than part  123   a . As a result, shutter  124  is able to tilt when only one of the entry ports ( 110   a ,  112   a ) is probed. Shutter  126  is configured and operates in substantially the same manner as shutter  124 . 
   Those of skill in the art recognize that the physical location of the elements illustrated in  FIGS. 11-15  can be moved or relocated while retaining the function described above. For example, in another exemplary embodiment of a receptacle in accordance with the present disclosure, the mechanical arm is replaced by a solenoid which differs from the existing trip solenoid incorporated in the design of a GFCI (see  FIG. 14A ). This solenoid is activated by the GFCI circuitry instead of the mechanical movement of the lifter. Other embodiments may incorporate, but are not limited to, a spring, muscle wire, etc. for substitution of the mechanical arm. 
   Advantages of this design include but are not limited to an electrical receptacle having an circuit interrupter which is tamper resistant and enabled to detect and prevent reverse wiring (e.g., via a shutter lock that is operatively connected in the receptacle to receive power from the power source connected to the receptacle). The electrical receptacle in accordance with the present disclosure includes a high performance, simple, and cost effective design. 
   Although the present disclosure has been described in accordance with the embodiments shown, one of ordinary skill in the art will readily recognize that there could be variations to the embodiment and these variations would be within the spirit and scope of the present disclosure. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims.