Leakage current detection interrupter with fire protection means

• US 8,154,831 B2
• Filed: 10/27/2009
• Issued: 04/10/2012
• Est. Priority Date: 12/23/2005
• Status: Active Grant

• Current Assignee: Heng Chen
• Original Assignee: General Protecht Group Incorporated
• Inventors: Wang, Fu, Ye, Xiangfa, Dai, Yong, Li, Xiaoyong
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Ieva, Nicholas
• Application Number:
  US12/606,405
• Publication Number:
  US 20100046128A1
• Time in Patent Office: 896 Days
• Field of Search: 361/42
• US Class Current: 361/42
• CPC Class Codes: H01B 7/328 comprising violation sensing means
• 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 3/334 with means to produce an artificial unbalance for other protection or monitoring reasons or remote control H02H3/338 takes precedence

Abstract

A leakage current detection interrupter with fire protection means comprising: (i) a movable assembly housing; (ii) two fixed contact holders each having a fixed contact point; (iii)) two movable contact holders each having a fixed end and a movable end with a movable contact point; (iv) a movable assembly that moves between a first position and a second position; (v) a resetting component; (vi) a resetting component spring; (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; (viii) an leakage current protection circuit assembled on a printed circuit board for detecting the fault condition; and (ix) a set of three electrical wires: a first wire, a second wire, and a third wire to an appliance, wherein the first wire and the second wire are protected by a plurality of protective shields.

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 first fixed contact, the second movable end has a second movable contact arranged for contacting the second 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 is used to bias the resetting component;

(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, wherein the fault condition comprises a condition when a leakage current is detected, and a condition when a ground fault is detected;

(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 LI-L, a second input LI-N, a third input LI-G, a first out put LO-P, a second output LO-N and a third output LO-G, 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;

(IX) a set of three electrical wires to an appliance, wherein a first wire connects the first input LI-L to the first output LO-P, a second wire connects the second input LI-N to the second output LO-N, and a third wire connects the third input LI-G to the third output LO-G of the leakage current detection interrupter, and wherein the first wire and the second wire are protected by a plurality of protective shields;

(X) a first switch K1 having a first terminal connected the first input LI-L, and a second terminal connected to the first output LO-P, for opening and closing the connection between the first input LI-L and the first output LO-P;

(XI) a second switch K2 having a first terminal connected the second input LI-N, and a second terminal connected to the second output LO-N, for opening and closing the connection between the second input LI-N and the second output LO-N;

(XII) an trip coil J1 having a first terminal connected to the first output LO-P and a second terminal, where the trip coil J1 simultaneously controls the opening and closing of the first switch K1 and the second switch K2;

(XIII) a leakage current detection unit having a metal oxide varister MOV with a first terminal and a second terminal, wherein the first terminal of the MOV is electrically coupled to the first input LI-I and the second terminal of the MOV is electrically coupled to the second input LI-N;

(XIV) a current interrupter having a relay having a first terminal and a second terminal, and a first resistor R1 having a first terminal and a second terminal, connected in serial such that the first terminal of the first resistor R1 is electrically coupled to the second terminal of the relay, wherein the leakage current detection unit detects a fault condition, causing a current passing through the relay, which connects the circuit of the trip coil J1 the both input lines LI-L and LI-N to activate the trip coil J1 and causes the first switch K1 and the second switch K2 to open the circuit simultaneously; and

(XV) a circuit condition indicator circuit having a light emit diode LED with an anode and a cathode and a second resistor R2 with a first terminal and a second terminal, wherein the anode of the LED is electrically coupled to the second output LO-N, the cathode of the LED is electrically coupled to the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is electrically coupled to the first output LO-P, wherein when the leakage current detection interrupter is in normal working condition, the LED is lit, and when the leakage current detection interrupter detects a leakage current, the LED is off,

wherein the leakage current detection unit comprises a first diode D1 having an anode and a cathode, wherein the anode is electrically coupled to the first input LI-L, and the cathode is electrically coupled to the first terminal of the relay, and a second diode D2 having an anode and a cathode, wherein the anode is electrically coupled to the second input LI-N, and the cathode is electrically coupled to the first terminal of the relay and the cathode of the first diode D1, wherein when a leakage current is detected by the first diode D1 and second diode D2 between the first input LI-L and second input LI-N, a current passes through the relay, causing the relay to close the circuit of the trip coil J1 and simultaneously disconnecting the first switch K1 and the second switch K2.

2. The leakage current detection interrupter of claim 1, wherein the movable assembly comprises:

(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 defined therebetween, a first contact support protruding from the first side surface away from the body, a second contact support protruding from the second side surface away from the body, wherein the body portion defines an opening through the center of the top surface through center of the bottom surface of the body, and a slot in proximity of the bottom surface through the first surface and the second surface of the body 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 tapered tip of the reset button 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 detection unit, 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.

3. The leakage current detection interrupter of claim 2, wherein the protective shield of the first wire, the second wire and the third wire comprises:

(i) an insulation layer outside of the first wire, the second wire and the third wire;

(ii) an outside protective insulation layer covering the first wire, the second wire and the third wire; and

(iii) a filling material to fill the space between the outside protective insulation layer, and the first wire, the second wire and the third wire.

4. The leakage current detection interrupter of claim 3, wherein the protective shield of the first wire, the second wire and the third wire further comprises a weaved copper shield outside of the insulation layer of the first wire and the second wire, wherein the weaved copper shield is electrically coupled to the second terminal of the first resistor R1.

5. The leakage current detection interrupter of claim 4, wherein the protective shield of the first wire, the second wire and the third wire further comprises a polyester conductive film outside of the weaved copper shield, wherein the polyester conductive film is electrically coupled to the second terminal of the first resistor R1.

6. The leakage current detection interrupter of claim 4, wherein the protective shield of the first wire, the second wire and the third wire further comprises an electricity conductive wire placed inside of the weaved copper shield, wherein the electricity conductive wire and the weaved copper shield are electrically coupled to the second terminal of the first resistor R1.

7. The leakage current detection interrupter of claim 3, wherein the protective shield of the first wire, the second wire and the third wire further comprises:

(i) a polyester electricity conductive film outside of the insulation layer of the first wire and the second wire; and

(ii) a conductive wire is placed inside of the polyester electricity conductive film, wherein the electricity conductive wire and the polyester electricity conductive film are electrically coupled to the second terminal of the first resistor R1.

8. A leakage current detection interrupter with fire protection means, 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 first fixed contact, the second movable end has a second movable contact arranged for contacting the second 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 with fire protection means 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 is used to bias the resetting component;

(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, 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 the first wire, the second wire, and the third wire are damaged by fire;

(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 LI-L, a second input LI-N, a third input LI-G, a first out put LO-P, a second output LO-N and a third output LO-G, wherein the leakage current protection circuit 300 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;

(IX) a set of three electrical wires to an appliance, wherein a first wire connects the first input LI-L to the first output LO-P, a second wire connects the second input LI-N to the second output LO-N, and a third wire connects the third input LI-G to the third output LO-G of the leakage current detection interrupter, and wherein the first wire and the second wire are protected by a plurality of protective shields;

(X) a first switch K1 having a first terminal connected the first input LI-L, and a second terminal connected to the first output LO-P, for opening and closing the connection between the first input LI-L and the first output LO-P;

(XI) a second switch K2 having a first terminal connected the second input LI-N, and a second terminal connected to the second output LO-N, for opening and closing the connection between the second input LI-N and the second output LO-N;

(XII) an trip coil J1 having a first terminal connected to the first output LO-P and a second terminal, where the trip coil J1 simultaneously controls the opening and closing of the first switch K1 and the second switch K2;

(XIII) a leakage current detection and fire hazard detection unit having a metal oxide varister MOV with a first terminal and a second terminal, wherein the first terminal of the MOV is electrically coupled to the first input LI-I and the second terminal of the MOV is electrically coupled to the second input LI-N;

(XIV) a current interrupter having a relay having a first terminal and a second terminal, and a first resistor R1 having a first terminal and a second terminal, connected in serial such that the first terminal of the first resistor R1 is electrically coupled to the second terminal of the relay, wherein the leakage current detection and fire hazard detection unit detects a fault condition, causing a current passing through the relay, which connects the circuit of the trip coil J1 the both input lines LI-L and LI-N to activate the trip coil J1 and causes the first switch K1 and the second switch K2 to open the circuit simultaneously; and

(XV) a circuit condition indicator circuit having a light emit diode LED with an anode and a cathode and a second resistor R2 with a first terminal and a second terminal wherein the anode of the LED is electrically coupled to the second output LO-N, the cathode of the LED is electrically coupled to the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is electrically coupled to the first output LO-P, wherein when the leakage current detection interrupter with fire protection means is in normal working condition, the LED is lit, and when the leakage current detection interrupter with fire protection means detects a leakage current or a fire hazard, the LED is off,

wherein the leakage current detection and fire hazard detection unit comprises;

(i) a leakage current detection unit having a first diode D1 having an anode and a cathode, wherein the anode is electrically coupled to the first input LI-L, and the cathode is electrically coupled to the first terminal of the relay, and a second diode D2 having an anode and a cathode, wherein the anode is electrically coupled to the second input LI-N, and the cathode is electrically coupled to the first terminal of the relay and the cathode of the first diode D1, wherein when a leakage current is detected by the first diode D1 and second diode D2 between the first input LI-L and second input LI-N, a current passes through the relay, causing the relay to close the circuit of the trip coil J1 and simultaneously disconnecting the first switch K1 and the second switch K2; and

(ii) a fire hazard detection unit, wherein the shields around the first wire and second wire are connected to the second terminal of the first resistor R1, wherein when the first wire and second wire are damaged by fire, the protective shields will short circuit the first output LO-P and the second output LO-N and the second terminal of the first resistor R1, causing the relay to close the circuit of the trip coil J1 and simultaneously disconnecting the first switch K1 and the second switch K2.

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

(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 defined therebetween, a first contact support protruding from the first side surface away from the body, a second contact support protruding from the second side surface away from the body, wherein the body portion defines an opening through the center of the top surface through center of the bottom surface of the body, and a slot in proximity of the bottom surface through the first surface and the second surface of the body 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 tapered tip of the reset button 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 detection and fire hazard detection unit, 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.

10. The leakage current detection interrupter with fire protection means of claim 9, wherein the protective shield of the first wire, the second wire and the third wire comprises:

(i) an insulation layer outside of the first wire, the second wire and the third wire;

(ii) an outside protective insulation layer covering the first wire, the second wire and the third wire; and

(iii) a filling material to fill the space between the outside protective insulation layer, and the first wire, the second wire and the third wire.

11. The leakage current detection interrupter with fire protection means of claim 10, wherein the protective shield of the first wire, the second wire and the third wire further comprises a weaved copper shield outside of the insulation layer of the first wire and the second wire, wherein the weaved copper shield is electrically coupled to the second terminal of the first resistor R1.

12. The leakage current detection interrupter with fire protection means of claim 11, wherein the protective shield of the first wire, the second wire and the third wire further comprises a polyester conductive film outside of the weaved copper shield, wherein the polyester conductive film is electrically coupled to the second terminal of the first resistor R1.

13. The leakage current detection interrupter with fire protection means of claim 11, wherein the protective shield of the first wire, the second wire and the third wire further comprises an electricity conductive wire placed inside of the weaved copper shield, wherein the electricity conductive wire and the weaved copper shield are electrically coupled to the second terminal of the first resistor R1.

14. The leakage current detection interrupter with fire protection means of claim 10, wherein the protective shield of the first wire, the second wire and the third wire further comprises:

(i) a polyester electricity conductive film outside of the insulation layer of the first wire and the second wire; and

(ii) a conductive wire is placed inside of the polyester electricity conductive film, wherein the electricity conductive wire and the polyester electricity conductive film are electrically coupled to the second terminal of the first resistor R1.