Circuits for circuit interrupting devices having automatic end of life testing function

• US 7,295,415 B2
• Filed: 09/21/2006
• Issued: 11/13/2007
• Est. Priority Date: 02/25/2005
• Status: Expired due to Fees

• Current Assignee: Huadao Huang
• Original Assignee: Huadao Huang
• Inventors: Huang, Huadao, Huayang, Lu
• Primary Examiner(s): Zarroli; Michael C.
• Application Number:
  US11/524,287
• Publication Number:
  US 20070014068A1
• Time in Patent Office: 418 Days
• Field of Search: 361/107, 361/115, 361/42, 361/535, 361/44, 335/18
• US Class Current: 361/107
• 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 83/04 with testing means for indicating the ability of the switch or relay to function properly
• CPC Class Codes: H01R 13/652 with earth pin, blade or socket
• CPC Class Codes: H01R 13/6691 with built-in signalling means H01R13/717 takes precedence
• CPC Class Codes: H01R 13/7135 with ground fault protector H01R13/7132 takes precedence
• CPC Class Codes: H01R 2103/00 Two poles
• CPC Class Codes: H01R 24/78 with additional earth or shield contacts

Abstract

The present invention provides a set of circuits which is capable of performing an automatic check on main components of a circuit interrupting device when the circuit interrupting device is properly powered and the device is at a tripped state to determine whether these main components function normally. The results of the automatic check can be detected by depressing a reset button in the circuit interrupting device. If the reset button can be depressed, the main components function normally. Alternatively, the results can be automatically displayed by a showing on the face lid of the circuit interrupting device of either a green light, which means that the main components function normally, or a red or yellow light or no light, which means that at least one of the main components in the circuit interrupting device does not function properly. The present invention also provides an end-of-service-life detection integrated circuit chip capable of receiving and transmitting an automatic check signal and determining whether or not the circuit interrupting device can be reset. The preferred circuit interrupting device is a ground fault circuit interrupter (GFCI).

Claims

1. An end-of-service-life integrated circuit chip (IC2) capable of performing an end-of-service-life test in a circuit interrupting device, said IC2 comprising:

a flip-flop latch circuit comprises a first transistor and a second transistor;

wherein said flip-flop latch circuit is adapted to receive and transmit a status signal when said circuit interrupting device is powered on and at a tripped state, allow said circuit interrupting device to be reset when components in a main circuit of said circuit interrupting device function normally, and disallow said circuit interrupting device to be reset when at least one of said components in said main circuit of said circuit interrupting device do not function properly; and

an emitter circuit comprising a third transistor;

wherein said emitter circuit is adapted to output said status signal from said flip-flop latch circuit through said third transistor to a simulated leakage current generation circuit of said circuit interrupting device to generate a simulated leakage current to test whether said components in said main circuit of said circuit interrupting device function normally; and

wherein said IC2 performs said end-of-service-life test without a depression of a reset button in said circuit interrupting device.

2. The IC2 according to claim 1, wherein said status signal is generated from a reset status checking circuit when said circuit interrupting device is powered on and a status test switch (KR1) in said reset status checking circuit is in a conductive state.

3. The IC2 according to claim 2, wherein said KR1 comprises a fixed frame, a first spring piece and a second spring piece;

and wherein in said conductive state, said first spring piece and said second spring piece are in contact with each other so that said status signal is generated and sent to said flip-flop latch circuit in said IC2.

4. The IC2 according to claim 2, wherein said KR1 is in said conductive state when said circuit interrupting device is at said tripped state.

5. The IC2 according to claim 1, wherein said flip-flop latch circuit in said IC2 allows said circuit interrupting device to be reset when a reset confirmed signal is sent to said flip-flop latch circuit.

6. The IC2 according to claim 5, wherein said reset confirmed signal is generated from a simulated current detection feedback circuit when said components in said main circuit function normally;

said reset confirmed signal being sent to said flip-flop latch circuit in said IC2.

7. The IC2 according to claim 1, wherein said flip-flop latch circuit transmits said reset confirmed signal to a reset confirmation circuit to allow said circuit interrupting device to be reset when said reset button in said circuit interrupting device is depressed.

8. The IC2 according to claim 7, wherein said reset confirmation circuit comprises a reset start switch (KR4) having 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 said main circuit and said second spring piece is adapted to connect to said IC2;

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

9. The IC2 according to claim 6, said IC2 further comprising an inverter circuit;

wherein said inverter circuit receives said reset confirmed signal from said simulated current detection feedback circuit when said components in said main circuit function normally and sends said reset confirmed signal to said flip-flop latch circuit.

10. The IC2 according to claim 7, said IC2 further comprising an end-of-service-life test affirmation circuit;

wherein said end-of-service-life test affirmation circuit receives said reset confirmed signal from said flip-flop latch circuit and sends said reset confirmed signal to said reset confirmation circuit and optionally to an output status display circuit;

said output status display circuit allowing a normal status indicating light to be turned on.

11. The IC2 according to claim 10, wherein said normal status indicating light is a green light-emitting diode.

12. The IC2 according to claim 1, wherein said IC2 further comprising feedback signal input circuit, a start and test input circuit;

a backup start and test input circuit; and

a backup power supply circuit.

13. The IC2 according to claim 2, wherein when said reset button is depressed, said KR1 is converted from said conductive state into a non-conductive state when said components in said main circuit function normally, which discontinues transmitting of said status signal to said flip-flop latch circuit in said IC2, which further discontinues said output of said status signal to said simulated leakage current generation circuit so that said generation of said simulated leakage current is discontinued.

14. The IC2 according to claim 13, wherein in said non-conductive state, said first spring piece and said second spring piece are separated from each other.

15. The IC2 according to claim 1, wherein said first transistor and said second transistor is replaced with a CMOS integrated circuit transistor compound set.

16. The IC2 according to claim 1, wherein when said at least one of said components in said main circuit does not function normally, no said reset confirmed signal is generated from said simulated current detection feedback circuit, so that no said reset confirmed signal is sent to said flip-flop latch circuit in said IC2 to allow said circuit interrupting device to reset.

17. The IC2 according to claim 1, wherein when at least one of said components in said main circuit does not function normally, said emitter circuit continuously sends said status signal to said simulated leakage current generation circuit which continuously generates said simulated leakage current;

wherein said simulated leakage current generation circuit comprises a failure status indicating circuit which contains a failure status indicating light;

wherein said failure status indicating light is turned on when said emitter circuit continuously sends said status signal to said simulated leakage current generation circuit.

18. The IC2 according to claim 12, wherein said failure status indicating light is a red or yellow light-emitting diode.

19. The IC2 according to claim 1, wherein said components of said main circuit comprising a differential transformer, a leakage current detection chip (IC1), a silicon control rectifier, and a solenoid coil.

20. The IC2 according to claim 6, wherein said simulated current detection feedback circuit is connected to said main circuit;

wherein when said simulated leakage current is passed through said main circuit and when said components of said main circuit function normally, a differential transformer in said main circuit detects said simulated leakage current and output an electrical imbalance signal to a leakage current detection integrated circuit chip (IC1) in said main circuit, which sends said electrical imbalance signal to a silicon controlled rectifier to turn on and supply power to a solenoid coil in a tripping device to discontinue an electricity continuity of said circuit interrupting device and to allow said reset confirmed signal to be generated in said simulated current detection feedback circuit.

21. The IC2 according to claim 19, wherein said simulated leakage current is further generated by a manual switch coupled to a test button;

whereby by depressing said test button, said simulated current detection feedback circuit generates said reset confirmed signal when said components of said main circuit function normally to allow said circuit interrupting device to reset.

22. A set of circuits in a circuit interrupting device capable of automatically performing a check on main components in said circuit interrupting device, said set of circuits comprising:

a main circuit which comprises a differential transformer, a leakage current detection chip (IC1), a silicon controlled rectifier, and a solenoid coil;

wherein said main circuit is capable of detecting a leakage current and/or a simulated leakage current;

wherein when said leakage current or said simulated leakage current is detected, said main circuit discontinues an electrical continuity of said circuit interrupting device;

a reset status checking circuit which comprises a status test switch (KR1);

wherein when KR1 is in a conductive state, said reset status checking circuit generates a status signal to be sent to an end-of-service-life integrated circuit chip (IC2);

an end-of-service-life detection circuit which comprises said IC2;

wherein when said main circuit is functioned properly, said IC2 receives a reset confirmed signal from a simulated current detection feedback circuit to allow said circuit interrupting device to be reset;

said simulated current detection feedback circuit being adapted to connect to said main circuit and generating said reset confirmed signal when said main circuit functions properly;

a simulated leakage current generation circuit which comprises a leakage current simulation circuit and optionally a failure status indicating circuit;

wherein said leakage current simulation circuit recognizes a status signal from said IC2 or a signal from a manual switch coupled to a test button; and

wherein when a failure status signal is received by said failure status indicating circuit, a failure status indicating light is turned on; and

a reset confirmation circuit which receives said reset confirmed signal from said IC2 when said main circuit functions properly;

wherein said reset confirmation circuit comprises a reset start switch (KR4) having a first spring piece and a second spring piece;

wherein said first spring piece is connected to said IC1 in said main circuit and said second spring piece is adapted to connect to said IC2;

whereby when said reset confirmation circuit receives said reset confirmed signal from said IC2 and said reset button is depressed, said first spring piece and said second spring piece are in a conductive state to allow said circuit interrupting device to be reset.

23. The set of circuits according to claim 22, wherein said set of circuits performs said check on main components in said circuit interrupting device when said circuit interrupting device is powered on and said circuit interrupting device is at a tripped state.

24. The set of circuits according to claim 23, wherein said set of circuits performs said check on main components in said circuit interrupting device without depressing a reset button in said circuit interrupting device.

25. The set of circuits according to claim 22, wherein said main components in said circuit interrupting device comprises said differential transformer, said IC1, said silicon controlled rectifier, said solenoid coil, and said IC2.

26. The set of circuits according to claim 22, wherein at least one of said main components in said circuit interrupting device does not function normally, said circuit interrupting device cannot be reset.

27. The set of circuits according to claim 22, further comprising an output status display circuit;

wherein when said main components of said circuit interrupting device function normally, said output status display circuit allowing a normal status indicating light to be turned on.

28. The set of circuits according to claim 27, wherein said normal status indicating light is a green light-emitting diode.

29. The set of circuits according to claim 22, wherein said failure status indicating light generated by said failure status indicating circuit in said simulated current generation circuit is a red or yellow light-emitting diode.

30. The set of circuits according to claim 22, wherein said circuit interrupting device is a ground fault circuit interrupter (GFCI), an arc fault circuit interrupter (AFCI), an immersion detection circuit interrupter, an appliance leakage circuit interrupter, or a circuit breaker.