Ground fault circuit interrupter with end of life indicators

• US 7,195,500 B2
• Filed: 02/27/2006
• Issued: 03/27/2007
• Est. Priority Date: 02/25/2005
• Status: Expired due to Fees

• Current Assignee: Huadao Huang
• Original Assignee: Huadao Huang
• Inventors: Huang, Huadao, Lu, Huayang
• Primary Examiner(s): Zarroli; Michael C.
• Application Number:
  US11/362,037
• Publication Number:
  US 20060193092A1
• Time in Patent Office: 393 Days
• Field of Search: 439/107, 439/535, 335/18, 361/42, 361/44
• US Class Current: 439/107
• CPC Class Codes: H01H 2071/044 Monitoring, detection or measuring systems to establish the end of life of the switching device, can also contain other on-line monitoring systems, e.g. for detecting mechanical failures
• CPC Class Codes: H01H 71/123 using a solid-state trip unit circuits H02H
• CPC Class Codes: H01H 83/04 with testing means for indicating the ability of the switch or relay to function properly

Abstract

The present invention provides a GFCI that not only has ground fault protection, but also is capable of providing reverse wiring protection as well as detection of end of the service life of the GFCI by way of utilizing an end of life detection control circuit in connection with the reset button. In addition, the GFCI of the present invention provides a forcible mechanical tripping assembly by way of utilizing the test button. Finally, the present invention provides method for detecting whether the service life of the GFCI has ended.

Claims

1. A circuit interrupting device containing a line side connection capable of being electrically connected to a source of electricity;

a load side connection capable of being electrically connected to a load side conductor; and

a user accessible load;

wherein said circuit interrupting device comprises;

a housing;

a trip assembly positioned in a base of said housing;

a circuit board positioned in said base of said housing;

said circuit board comprising

a first pair of flexible metal pieces having a first end and a second end;

wherein said first pair of flexible metal pieces is operationally connected to power source input terminals;

said first end of each of said first pair of flexible metal pieces passing through a differential transformer to be operationally connected to a hot input line or a neutral input line;

said second end of each of said second pair of flexible metal pieces having a movable contact point;

a second pair of flexible metal pieces having a first end and a second end;

wherein said first end of each of said first pair of flexible metal pieces is operationally connected to a hot power output terminal or a neutral power output terminal;

each of said second pair of flexible metal pieces having a movable contact point;

a pair of output conductors positioned in a central portion of said housing;

wherein each of said output conductors contains a pair of fixed contact points;

wherein said movable contact point of each of said first pair of flexible metal pieces and said movable contact point of each of second pair of flexible metal pieces are capable of connecting/disconnecting to each of said fixed contact points of said pair of output conductors.

2. The circuit interrupting device according to claim 1, wherein said trip assembly comprises a tripping device, a locking member, a locking spring, a tripping lever, and a solenoid coil.

3. The circuit interrupting device according to claim 2, wherein said tripping device is positioned underneath a reset button;

said tripping device having a central aperture to receive a directional lock which is coupled to said reset button;

said directional lock having a blunt end;

said directional lock being movable in a vertical direction in said aperture;

wherein said locking member is L-shaped, containing a horizontal side extending into said tripping device and through the aperture and a vertical side having an inner surface and an outer surface;

said horizontal side of said locking member having an opening therein and being movable through said aperture in a horizontal direction between an aligned position in which the opening of said locking member is aligned with said blunt end of said directional lock and a misaligned position in which the opening is misaligned with said blunt end of said directional lock;

said locking spring being located between a side wall of said tripping device and said inner surface of said vertical side of said L-shaped locking member;

said solenoid coil being positioned at said outer surface of said L-shaped locking member;

said solenoid coil having a movable plunger;

whereby when said solenoid coil is energized, said plunger moves towards said outer surface of said vertical side of said locking member, thereby moving said locking member into said aligned position; and

said tripping lever being connected to a hole at said horizontal side of said L-shaped locking member.

4. The circuit interrupting device according to claim 2, wherein said tripping device comprises a pair of lifting arms positioned below each of said movable contacts points.

5. The circuit interrupting device according to claim 4, wherein each of said movable contact points of said first pair of said flexible metal pieces is in a different cross sectional plane from said each of said movable contact points of said second pair of said flexible metal pieces.

6. The circuit interrupting device according to claim 1, wherein a bottom of said tripping device is operationally connected to said circuit board through a power source switch containing a movable contact located at said bottom of said tripping device and a fixed contact located at said circuit board;

whereby when said reset button is depressed, said movable contact is in contact with said fixed contact so as to close said power source switch and when said reset button is released, said movable contact is detached from said fixed contact so as to open said power source switch.

7. The circuit interrupting device according to claim 6, further comprising an end of life detection control integrated circuit (IC);

wherein said end of life detection control IC starts to operate when said power source switch is closed.

8. The circuit interrupting device according to claim 7, wherein said end of life detection circuit generates a simulated fault to detect said circuit interrupting device;

whereby when said circuit interrupting device functions properly, the depression and release of said reset button reestablish said electrical continuity and when said circuit interrupting device fails to detect said simulated fault, the depression and release of said reset button prevent said electrical continuity.

9. The circuit interrupting device according to claim 7, wherein said end of life detection control IC is an IC20060215.

10. The circuit interrupting device according to claim 7, wherein said end of life detection control IC is connected to a leakage current detection control integrated circuit (IC).

11. The circuit interrupting device according to claim 10, wherein said leakage current detection control IC is an RV4145.

12. The circuit interrupting device according to claim 10, wherein said leakage current detection control IC is connected to the differential transformer;

whereby when a fault is detected, the differential transformer sends a signal to said leakage current detection control IC, which in turn sends a signal to a silicon control rectifier (SCR) to trigger said trip assembly to interrupt said electrical continuity.

13. The circuit interrupting device according to claim 7, further comprising an indicator light;

said indicator light is connected to said output terminals;

whereby when said device is not functional when said reset button is depressed, said indicator light is lighted.

14. The circuit interrupting device according to claim 1, wherein each of said pair of said output conductor comprises a pair of gripping wing pieces protruded to output socket holes at a front lid of said housing.

15. The circuit interrupting device according to claim 2, wherein said device has a test button at a front lid of said housing;

wherein said test button has a tail end which is extended to an end of said tripping lever;

wherein when said test button is depressed, said tail end of said test button presses against said tripping lever, which causes said device to mechanically trip.

16. The circuit interrupting device according to claim 1, further comprising a position limiting piece below each of said first and said second pair of flexible metal pieces.

17. The circuit interrupting device according to claim 7, wherein said circuit interrupting device has reverse wire protection.

18. A method for detecting an end of life of a circuit interrupting device comprising:

depressing said reset button of said circuit interrupting device according to claim 7;

releasing said reset button; and

observing whether said circuit interrupting device has been reset.

19. A method for detecting an end of life of a circuit interrupting device comprising:

depressing said reset button of said circuit interrupting device according to claim 7;

releasing said reset button; and

monitoring said indicator light.