Leakage current detection interrupter with fire protection means

• US 20070146946A1
• Filed: 10/26/2006
• Published: 06/28/2007
• Est. Priority Date: 12/23/2005
• Status: Active Grant

• Current Assignee: Heng Chen
• Original Assignee: General Protecht Group Incorporated
• Inventors: Li, Xiaoyong, Wang, Fu, Chen, Wusheng, Dai, Yong, Song, Huaiyin
• Granted Patent: US 7,889,464 B2
• Time in Patent Office: Days
• US Class Current: 361/42
• CPC Class Codes: H01H 73/44 reset by push-button, pull-knob or slide
• CPC Class Codes: H01H 83/04 with testing means for indicating the ability of the switch or relay to function properly
• CPC Class Codes: H01H 83/14 operated by imbalance of two or more currents or voltages, e.g. for differential protection
• CPC Class Codes: H02H 3/33 using summation current transformers H02H3/347 takes precedence
• CPC Class Codes: H02H 5/10 responsive to mechanical injury, e.g. rupture of line, breakage of earth connection

Abstract

A leakage current detection interrupter with fire protection means, comprising: (i) a leakage current protection circuit, (ii) an electrical cord with metallic fire shields, and (iii) a fire protection circuit, wherein, in operation, the leakage current protection circuit and the fire protection circuit detect a fault condition including a leakage current, a ground fault and a fire hazard, and disconnect the source of electricity from the at least one user accessible load when leakage current, ground fault or fire hazard is detected. The electrical cord with metallic fire shields, the fire protection circuit, and the indicator circuit can be combined with any ground fault circuit interrupter, arc fault circuit interrupter, immerse detection circuit interrupter, appliance leakage current interrupter and electronic leakage current interrupter.

Claims

1. A leakage current detection interrupter, comprising:

(i) a movable assembly housing having a first side surface and an opposite, second side surface, and a body defined therebetween, wherein the body defines two vertical openings on the first side surface and the second surface;

(ii) a first fixed contact holder having a first fixed contact point, and a second fixed contact holder having a second fixed contact point;

(iii) a first movable contact holder and a second movable contact holder, each having a fixed end attached to the movable assembly housing and a movable end, wherein the first movable end has a first movable contact arranged for contacting the second fixed contact, the second movable end has a second movable contact arranged for contacting the first fixed contact;

(iv) a movable assembly that moves between a first position in which each fixed contact makes contact with the respective movable contact and a second position in which the fixed contacts are separated from the movable contacts;

(v) a resetting component having a first end accessible to a user for resetting the leakage current detection interrupter and a second end with a tapered tip and a notch, which, when the movable assembly is in the first position, is engaged with the movable assembly;

(vi) a resetting component spring which releases the resetting component and disengage the movable assembly;

(vii) an electromagnetic tripping component, which, when energized, which is responsive to a fault condition, causes the movable assembly to be in the second position from the first position, thereby causing the resetting component to disengage the movable assembly; and

(viii) an leakage current protection circuit assembled on a printed circuit board for detecting the fault condition, wherein the leakage current protection circuit comprises a first input, a second input, a third input, a first output, a second output and a third output, wherein the leakage current protection circuit is capable of detecting a fault condition and energizing the electromagnetic tripping component to cause resetting component to disengage the movable assembly in responsive to the fault condition.

2. The leakage current detection interrupter of claim 1, wherein the fault condition comprises a condition when a leakage current is detected, and a condition when a ground fault is detected.

3. The leakage current detection interrupter of claim 2, wherein the leakage current protection circuit further comprises:

(i) a first switch having a first terminal connected the first input, and a second terminal connected to the first output, for opening and closing the connection between the first input and the first output;

(ii) a second switch having a first terminal connected the first input, and a second terminal connected to the first output, for opening and closing the connection between the first input and the first output;

(iii) an trip coil having a first terminal connected to the first input and a second terminal, where the trip coil simultaneously controls the opening and closing of the first switch and the second switch;

(iv) an inductive coil having a first terminal and a second terminal for detecting current difference in the line between the first input and the first output and the line between the second input and the second output; and

(v) a leakage current detection circuit having a first input connected to the first terminal of the inductive coil and a second input connected to the second terminal of the inductive coil, a first output terminal connected to the second terminal of the trip coil and a second output terminal connected to the second input, wherein the leakage current detection circuit detects a fault condition through the inductive coil and passes a current to the first output terminal to activate the trip coil and causes the first switch and the second switch to open the circuit simultaneously.

4. The leakage current detection circuit of claim 3, further comprising:

(i) a first capacitor connected in parallel to the first input and the second input;

(ii) an integrated circuit having a first terminal, a second terminal, a third terminal connected to the second input, a fourth terminal connected to the second output terminal, a fifth terminal, a sixth terminal, a seventh terminal, and an eighth terminal;

(iii) a first resistor having a first terminal connected to the first input, and a second terminal connected to the second terminal of the integrated circuit;

(iv) a second resistor having a first terminal connected to the first terminal of the integrated circuit and the a second terminal connected to the second terminal of the integrated circuit;

(v) a second capacitor having a first terminal connected to the sixth terminal of the integrated circuit, and a second terminal connected to the second output terminal;

(vi) a third capacitor having a first terminal connected to the seventh terminal of the integrated circuit, and a second output terminal;

(vii) a fourth capacitor having a first terminal connected to the eighth terminal of the integrated circuit, and a second terminal connected to the second output terminal;

(viii) a silicon controlled rectifier having a cathode connected to the second output terminal, a gate connected to the first terminal of the third capacitor and the seventh terminal of the integrated circuit, and an anode connected to the first output terminal;

(ix) a fifth resistor having a first terminal connected to the first output terminal and the anode of the silicon controlled rectifier, and a second terminal; and

(x) a sixth diode having an anode connected to the second terminal of the fifth resistor, and a cathode connected to the fifth terminal of the integrated circuit.

5. The leakage current detection interrupter of claim 4, wherein the movable assembly comprising:

(i) a trip coil frame with an opening through the center of the trip coil frame and with the electromagnetic tripping component wound on the trip coil frame;

(ii) a magnetic core having a first end and an opposite, second end, with the first end positioned outside of the center opening of the trip coil frame and the second end positioned inside of the center opening of the trip coil frame, wherein the magnetic core stays in the first position when no fault condition is detected and moves to the second position when a fault condition is detected and the electromagnetic tripping component is energized;

(iii) a core spring to keep the magnetic core in the first position when no fault condition is detected and the electromagnetic tripping component is not energized;

(iv) a resetting component locker having a upper portion and a lower portion, wherein the lower portion is substantially perpendicular to the upper portion, the upper portion is slidably attached to the first end of the magnetic core outside of the center opening of the trip coil frame; and

(v) a balance frame having a first surface, an opposite, second surface, a first side surface, an opposite, second side surface, a top surface and an opposite, bottom surface, and a body portion defined therebetween, a first contact support protruding from the first side surface away from the body portion, a second contact support protruding from the second side surface away from the body portion, wherein the body portion defines an opening through the center of the top surface through center of the bottom surface of the body portion, and a slot in proximity of the bottom surface through the first surface and the second surface of the body portion where the lower portion of the resetting component locker is slidably inserted, and wherein the balance frame is able to slide up and down along the openings of the movable assembly housing;

wherein in operation, when the resetting component is pressed, the notch of the resetting component pushes the resetting component locker horizontally so the resetting component locker is engaged with the notch of the resetting component and locks resetting component, and the resilience of the resetting component spring pulls the balance frame and the resetting component locker upward such that the first movable contact holder and the second movable contact holder are pushed upward by the contact supports on both sides of the balance frame and causes the movable assembly in the first position, and when a fault condition is detected by the leakage current protection circuit, a current is directed to the electromagnetic tripping component causing an electromagnetic force to pull the magnetic core towards the trip coil frame, along with the resetting component locker, such that the resetting component locker is released from the engagement with the resetting component, and the balance frame together with the resetting component locker moves downward at the action of the resilience force of the first movable contact holder and the second movable contact holder to set the movable assembly in the second position.

6. A leakage current detection interrupter with fire protection means, comprising:

(i) a leakage current protection circuit having a line phase terminal, a line neutral terminal, a line ground terminal, a first output, a second output and a third output, wherein the line phase terminal, the line neutral terminal, and the line ground terminal are connectable to a source of electricity, and the first output, the second output and the third output are connectable to at least one user accessible load;

(ii) an electrical cord with metallic fire shields having a fire protection terminal;

(iii) a fire protection circuit having a first terminal connected to the line phase terminal of the leakage current protection circuit, a second terminal connected to the line neutral terminal, and a third terminal; and

(iv) an indicator circuit having a phase terminal, a neutral terminal and a ground terminal, a protection terminal, a load phase terminal connected to the phase terminal, a load neutral terminal connected to the neutral terminal and a load ground terminal connected to the ground terminal,

wherein, in operation, the leakage current protection circuit and the fire protection circuit detect a fault condition and disconnects the source of electricity from the at least one user accessible load when leakage current, ground fault or fire hazard is detected.

7. The leakage current detection interrupter with fire protection means of claim 6, wherein the fault condition comprises a condition when a leakage current is detected, a condition when a ground fault is detected, and a condition when a fire hazard is detected.

8. A leakage current detection interrupter with fire protection means of claim 7, wherein the leakage current protection circuit further comprises:

(i) a movable assembly housing having a first side surface and an opposite, second side surface, and a body defined therebetween, wherein the body defines two vertical openings on the first side surface and the second surface;

(ii) a first fixed contact holder having a first fixed contact point, and a second fixed contact holder having a second fixed contact point;

(iii) a first movable contact holder and a second movable contact holder, each having a fixed end attached to the movable assembly housing and a movable end, wherein the first movable end has a first movable contact arranged for contacting the second fixed contact, the second movable end has a second movable contact arranged for contacting the first fixed contact;

(iv) a movable assembly that moves between a first position in which each fixed contact makes contact with the respective movable contact and a second position in which the fixed contacts are separated from the movable contacts;

(v) a resetting component having a first end accessible to a user for resetting the leakage current detection interrupter and a second end with a tapered tip and a notch, which, when the movable assembly is in the first position, is engaged with the movable assembly;

(vi) a resetting component spring which releases the resetting component and disengage the movable assembly;

(vii) an electromagnetic tripping component, which, when energized, which is responsive to a fault condition, causes the movable assembly to be in the second position from the first position, thereby causing the resetting component to disengage the movable assembly; and

(viii) an leakage current protection circuit assembled on a printed circuit board for detecting the fault condition, wherein the leakage current protection circuit comprises a first input, a second input, a third input, a first output, a second output and a third output, wherein the leakage current protection circuit is capable of detecting a fault condition and energizing the electromagnetic tripping component to cause resetting component to disengage the movable assembly in responsive to the fault condition.

9. The leakage current detection interrupter with fire protection means of claim 8, wherein the leakage current protection circuit further comprises:

(i) a first switch having a first terminal connected the first input, and a second terminal connected to the first output, for opening and closing the connection between the first input and the first output;

(ii) a second switch having a first terminal connected the first input, and a second terminal connected to the first output, for opening and closing the connection between the first input and the first output;

(iii) an trip coil having a first terminal connected to the first input and a second terminal, where the trip coil simultaneously controls the opening and closing of the first switch and the second switch;

(iv) an inductive coil having a first terminal and a second terminal for detecting current difference in the line between the first input and the first output and the line between the second input and the second output; and

(v) a leakage current detection circuit having a first input connected to the first terminal of the inductive coil and a second input connected to the second terminal of the inductive coil, a first output terminal connected to the second terminal of the trip coil and a second output terminal connected to the second input, wherein the leakage current detection circuit detects a fault condition through the inductive coil and passes a current to the first output terminal to activate the trip coil and causes the first switch and the second switch to open the circuit simultaneously.

10. The leakage current detection interrupter with fire protection means of claim 9, wherein the leakage current detection circuit further comprises:

(i) a first capacitor connected in parallel to the first input and the second input;

(ii) an integrated circuit having a first terminal, a second terminal, a third terminal connected to the second input, a fourth terminal connected to the second output terminal, a fifth terminal, a sixth terminal, a seventh terminal, and an eighth terminal;

(iii) a first resistor having a first terminal connected to the first input, and a second terminal connected to the second terminal of the integrated circuit;

(iv) a second resistor having a first terminal connected to the first terminal of the integrated circuit and the a second terminal connected to the second terminal of the integrated circuit;

(v) a second capacitor having a first terminal connected to the sixth terminal of the integrated circuit, and a second terminal connected to the second output terminal;

(vi) a third capacitor having a first terminal connected to the seventh terminal of the integrated circuit, and a second output terminal;

(vii) a fourth capacitor having a first terminal connected to the eighth terminal of the integrated circuit, and a second terminal connected to the second output terminal;

(viii) a silicon controlled rectifier having a cathode connected to the second output terminal, a gate connected to the first terminal of the third capacitor and the seventh terminal of the integrated circuit, and an anode connected to the first output terminal;

(ix) a fifth resistor having a first terminal connected to the first output terminal and the anode of the silicon controlled rectifier, and a second terminal; and

(x) a sixth diode having an anode connected to the second terminal of the fifth resistor, and a cathode connected to the fifth terminal of the integrated circuit.

11. The leakage current detection interrupter with fire protection means of claim 10, wherein the movable assembly comprising:

(i) a trip coil frame with an opening through the center of the trip coil frame and with the electromagnetic tripping component wound on the trip coil frame;

(ii) a magnetic core having a first end and an opposite, second end, with the first end positioned outside of the center opening of the trip coil frame and the second end positioned inside of the center opening of the trip coil frame, wherein the magnetic core stays in the first position when no fault condition is detected and moves to the second position when a fault condition is detected and the electromagnetic tripping component is energized;

(iii) a core spring to keep the magnetic core in the first position when no fault condition is detected and the electromagnetic tripping component is not energized;

(iv) a resetting component locker having a upper portion and a lower portion, wherein the lower portion is substantially perpendicular to the upper portion, the upper portion is slidably attached to the first end of the magnetic core outside of the center opening of the trip coil frame; and

(v) a balance frame having a first surface, an opposite, second surface, a first side surface, an opposite, second side surface, a top surface and an opposite, bottom surface, and a body portion defined therebetween, a first contact support protruding from the first side surface away from the body portion, a second contact support protruding from the second side surface away from the body portion, wherein the body portion defines an opening through the center of the top surface through center of the bottom surface of the body portion, and a slot in proximity of the bottom surface through the first surface and the second surface of the body portion where the lower portion of the resetting component locker is slidably inserted, and wherein the balance frame is able to slide up and down along the openings of the movable assembly housing,

wherein in operation, when the resetting component is pressed, the notch of the resetting component pushes the resetting component locker horizontally so the resetting component locker is engaged with the notch of the resetting component and locks resetting component, and the resilience of the resetting component spring pulls the balance frame and the resetting component locker upward such that the first movable contact holder and the second movable contact holder are pushed upward by the contact supports on both sides of the balance frame and causes the movable assembly in the first position, and when a fault condition is detected by the leakage current protection circuit, a current is directed to the electromagnetic tripping component causing an electromagnetic force to pull the magnetic core towards the trip coil frame, along with the resetting component locker, such that the resetting component locker is released from the engagement with the resetting component, and the balance frame together with the resetting component locker moves downward at the action of the resilience force of the first movable contact holder and the second movable contact holder to set the movable assembly in the second position.

12. The leakage current detection interrupter with fire protection means of claim 11, wherein electromagnetic tripping component is covered by a metal shield on four sides for protecting electromagnetic tripping component from failing during a fire condition.

13. The leakage current detection interrupter with fire protection means of claim 12, wherein the electrical cord with metallic fire shields comprises:

(i) a neutral wire;

(ii) a phase wire;

(iii) a ground wire;

(iv) a fire protection terminal; and

(v) metallic fire shields covering all wires herein,

wherein the electrical cord has a first end for connecting to the leakage current detection interrupter with fire protection means, and a second end for connecting to at least one user accessible load.

14. The leakage current detection interrupter with fire protection means of claim 13, wherein the fire protection circuit comprises:

(i) a second rectifying diode having a cathode connected to the line phase terminal, and an anode;

(ii) a second rectifying diode having a cathode connected to the line neutral terminal, and an anode; and

(iii) a fourth resistor having a first terminal connected to the anode of the second rectifying diode and the anode of the third rectifying diode, and a second terminal connected to the fire protection terminal,

wherein in operation, the second rectifying diode and the third rectifying diode provide a by-pass to the current through the leakage current detection interrupter, when the electrical cord with metallic fire shields is damaged, or a fire hazard occurs, the leakage current detection interrupter disconnects the at least one user accessible load from the source of electricity.

15. The leakage current detection interrupter with fire protection means of claim 14, wherein the second end of the electrical cord with metallic fire shield comprises at least one electrical plug.

16. The leakage current detection interrupter with fire protection means of claim 14, wherein the second end of the electrical cord with metallic fire shield comprises at least one electrical socket.

17. The leakage current detection interrupter with fire protection means of claim 14, wherein the indicator circuit further comprises:

(i) a fourth diode having an anode connected to the protection terminal, and a cathode;

(ii) a ninth resistor having a first terminal connected to the cathode of the fourth diode, and a second terminal; and

(iii) a fifth light emitting diode (LED) having an anode connected to a second terminal of ninth resistor and a cathode connected to the load neutral terminal,

wherein in operation, when the leakage current detection interrupter with fire protection means does not detect any fault condition, the LED lights up indicating normal working condition, and if the electrical cord with metallic fire shields is damaged such that the metallic fire shield covering both the phase wire and the neutral wire is exposed to the phase wire, or neutral wire, or both, the LED is not lit.

18. A leakage current detection interrupter, comprising:

(i) a movable assembly housing having a first side surface and an opposite, second side surface, and a body defined therebetween, wherein the body defines two vertical openings on the first side surface and the second surface;

(ii) a first fixed contact holders having a first fixed contact point, and a second fixed contact holders having a second fixed contact point;

(iii) a first movable contact holder and a second movable contact holder, each having a fixed end attached to the movable assembly housing and a movable end, wherein the first movable end has a first movable contact arranged for contacting the second fixed contact, the second movable end has a second movable contact arranged for contacting the first fixed contact;

(iv) a movable assembly that moves between a first position in which each fixed contact makes contact with the respective movable contact and a second position in which the fixed contacts are separated from the movable contacts;

(v) a resetting component having a first end accessible to a user for resetting the leakage current detection interrupter and a second end with a tapered tip and a notch, which, when the movable assembly is in the first position, is engaged with the movable assembly;

(vi) a resetting component spring which releases the resetting component and disengage the movable assembly; and

(vii) an electromagnetic tripping component, which, when energized, which is responsive to a fault condition, causes the movable assembly to be in the second position from the first position, thereby causing the resetting component to disengage the movable assembly.

19. The leakage current detection interrupter of claim 18, wherein the fault condition comprises a condition when a leakage current is detected, and a condition when a ground fault is detected.

20. The leakage current detection interrupter of claim 19, wherein the movable assembly comprising:

(i) a trip coil frame with an opening through the center of the trip coil frame and with the electromagnetic tripping component wound on the trip coil frame;

(ii) a magnetic core having a first end and an opposite, second end, with the first end positioned outside of the center opening of the trip coil frame and the second end positioned inside of the center opening of the trip coil frame, wherein the magnetic core stays in the first position when no fault condition is detected and moves to the second position when a fault condition is detected and the electromagnetic tripping component is energized;

(iii) a core spring to keep the magnetic core in the first position when no fault condition is detected and the electromagnetic tripping component is not energized;

(iv) a resetting component locker having a upper portion and a lower portion, wherein the lower portion is substantially perpendicular to the upper portion, the upper portion is slidably attached to the first end of the magnetic core outside of the center opening of the trip coil frame; and

(v) a balance frame having a first surface, an opposite, second surface, a first side surface, an opposite, second side surface, a top surface and an opposite, bottom surface, and a body portion defined therebetween, a first contact support protruding from the first side surface away from the body portion, a second contact support protruding from the second side surface away from the body portion, wherein the body portion defines an opening through the center of the top surface through center of the bottom surface of the body portion, and a slot in proximity of the bottom surface through the first surface and the second surface of the body portion where the lower portion of the resetting component locker is slidably inserted, and wherein the balance frame is able to slide up and down along the openings of the movable assembly housing,

wherein in operation, when the resetting component is pressed, the notch of the resetting component pushes the resetting component locker horizontally so the resetting component locker is engaged with the notch of the resetting component and locks resetting component, and the resilience of the resetting component spring pulls the balance frame and the resetting component locker upward such that the first movable contact holder and the second movable contact holder are pushed upward by the contact supports on both sides of the balance frame and causes the movable assembly in the first position, and when a fault condition is detected by the leakage current protection circuit, a current is directed to the electromagnetic tripping component causing an electromagnetic force to pull the magnetic core towards the trip coil frame, along with the resetting component locker, such that the resetting component locker is released from the engagement with the resetting component, and the balance frame together with the resetting component locker moves downward at the action of the resilience force of the first movable contact holder and the second movable contact holder to set the movable assembly in the second position.