Ground fault circuit interrupter containing a dual-function test button

• US 7,289,306 B2
• Filed: 12/06/2006
• Issued: 10/30/2007
• Est. Priority Date: 02/25/2005
• Status: Expired due to Fees

• Current Assignee: Huadao Huang
• Original Assignee: Huadao Huang
• Inventors: Huang, Huadao
• Primary Examiner(s): Zarroli; Michael C.
• Application Number:
  US11/634,074
• Publication Number:
  US 20070076337A1
• Time in Patent Office: 328 Days
• Field of Search: 361/107, 361/42, 335/17, 335/18
• US Class Current: 361/42
• 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 83/04 with testing means for indicating the ability of the switch or relay to function properly

Abstract

The present invention provides a circuit interrupting device, preferably a ground fault circuit interrupter (GFCI), which contains a dual-function test button having a short pole and a long pole positioned underneath the dual-function test button. When the GFCI is properly wired and powered, and preferably in a reset state, a first-level depression of the dual-function test button allows the short pole to close a flexible switch (KT) to electrically connect a power input end to a power output end and generate a leakage current to test the components of the GFCI. If all of the components are functioned properly, the GFCI can be reset. If not, the GFCI cannot be reset. When the GFCI is miswired or reverse wired and not powered, the first-level depression of the dual-function test button does not test the components of the GFCI. However, a second-level depression of the dual-function test button allows the long pole presses against a tripping lever on a locking member in a tripping device which mechanically trip the GFCI. The present invention further provides an end-of-life detection circuit which can automatically generates a simulated leakage current to test the components in the GFCI. If one or more components are not functioned properly, the end-of-life circuit prevents the GFCI from resetting.

Claims

1. A circuit interrupting device comprises:

a housing;

a circuit board located within said housing;

a tripping device capable of tripping said circuit interrupting device to cause electrical discontinuity between a line side connection, a load side connection, and a user accessible load side connection when a fault occurs;

a reset button; and

a dual-function test button having a first pole and a second pole underneath said dual-function test button;

wherein when said circuit interrupting device is properly wired and/or powered, a first-level depression of said dual-function test button allows said first pole to close a flexible switch (KT) to generate a leakage current to test whether components of said circuit interrupting device are functioned properly;

wherein when said circuit interrupting device is not properly wired or powered, said first-level depression of said dual-function test button does not generate said leakage current, but a second-level depression of said dual-function test button allows said second pole to adapt to mechanically trip said circuit interrupting device.

2. The circuit interrupting device according to claim 1, wherein said circuit interrupting device is a ground fault circuit interrupter.

3. The circuit interrupting device according to claim 1, wherein said fault is a ground fault, an arc fault, an appliance leakage fault, an immersion fault or a simulated leakage current.

4. The circuit interrupting device according to claim 1, wherein said circuit interrupting device is at a reset state when said dual-function test button is depressed.

5. The circuit interrupting device according to claim 1, wherein when said components of said circuit interrupting device are functioned properly, said reset button is capable of being reset;

and wherein when one or more of said components of said circuit interrupting device are not functioned properly, said reset button cannot be reset.

6. The circuit interrupting device according to claim 1, wherein said components of said circuit interrupting device comprise a differential transformer, a leakage current detection chip (IC1), a silicon controlled rectifier (SCR), and a solenoid coil.

7. The circuit interrupting device according to claim 1, wherein said first pole is shorter than said second pole.

8. The circuit interrupting device according to claim 1, wherein said second-level depression of said dual-function test button requires a user to depress said dual-function test button further.

9. The circuit interrupting device according to claim 1, wherein said flexible switch (KT) is located beneath said first pole.

10. The circuit interrupting device according to claim 1, wherein said flexible switch (KT) comprises a flexible metal sheet;

wherein a first end of said flexible metal sheet is electrically connected to a power output end and a second end of said flexible metal sheet is capable of being electrically connected to a power input end when said KT is closed.

11. The circuit interrupting device according to claim 1, wherein said leakage current is generated via a resistor which is operatively connected to said KT.

12. The circuit interrupting device according to claim 1, wherein further comprising a first pair of flexible metal pieces and a second pair of flexible metal pieces;

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

a first end of each of said first pair of flexible metal piece being operatively connected to a hot input line or a neutral input line;

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

wherein said second pair of flexible metal pieces is operatively connected to a hot power output end or a neutral power output end;

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

13. The circuit interrupting device according to claim 12, further comprising a pair of output conductors positioned in 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.

14. The circuit interrupting device according to claim 13, 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.

15. 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 upper cover of said housing.

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

17. The circuit interrupting device according to claim 16, wherein said tripper is located underneath said reset button;

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

said directional lock being movable in said aperture of said tripper.

18. The circuit interrupting device according to claim 16, wherein said locking member has a horizontal side extending into said tripper and through the aperture and a vertical side having an inner surface and an outer surface;

said horizontal side of said locking member having a through hole therein and being movable in a horizontal direction between an aligned position in which said through hole of said locking member is aligned with said aperture of said tripper and a misaligned position in which said through hole of said locking member is misaligned with said aperture of said tripper.

19. The circuit interrupting device according to claim 16, wherein said locking spring is located between a side wall of said tripper and said inner surface of said vertical side of said locking member.

20. The circuit interrupting device according to claim 16, wherein said solenoid coil is positioned at a distance down from said outer surface of said locking member;

said solenoid coil having an iron core;

whereby when said solenoid coil is energized, said iron core moves towards and plunges onto said outer surface of said vertical side of said locking member, thereby moving said locking member into said aligned position.

21. The circuit interrupting device according to claim 16, wherein a first end of said tripping lever is connected to a hole at said horizontal side of said locking member;

and wherein said second end of said tripping lever is distanced down under said second pole of said dual-function test button;

whereby said second-level depression of said dual-function test button allows said second pole to press against said second end of said tripping lever to cause said tripper and said locking member to move to said aligned position so as to mechanically trip said circuit interrupting device.

22. The circuit interrupting device according to claim 21, wherein without said second-level depression of said dual-function test button, said second pole does not press against said second end of said tripping lever to mechanically trip said circuit interrupting device.

23. The circuit interrupting device according to claim 1, further comprising an end of life detection chip (IC2) which is capable of automatically generating a simulated leakage current to test said components of said circuit interrupting device when said circuit interrupting device is properly wired and powered and is at a tripped position;

wherein when said components of said circuit interrupting device are functioned properly, said IC2 sends a signal to a reset confirmation circuit which allows said reset button to be reset; and

wherein when one or more of said components of said circuit interrupting device are not functioned properly, said IC2 sends a signal to said reset confirmation circuit which prevents said circuit interrupting device from resetting.

24. The circuit interrupting device according to claim 23, wherein said reset confirmation circuit comprises a reset start switch (KR4).

25. The circuit interrupting device according to claim 24, wherein said KR4 has a first spring piece and a second spring piece;

wherein said first spring piece is connected to a leakage current detection integrated circuit chip (IC1) in a main circuit and said second spring piece is adapted to connect to said IC2; and

wherein when said reset confirmation circuit receives said signal from said IC2 to allow reset and then said reset button is depressed, said first spring piece and said second spring piece are in a conductive state to allow reset.