GB2439359A

GB2439359A - A dual-magnetic control type high-sensitive leakage protector

Info

Publication number: GB2439359A
Application number: GB0706293A
Authority: GB
Inventors: Yu Chen; Zhenqing Zhu
Original assignee: Chint Group Corp
Current assignee: Chint Group Corp
Priority date: 2006-06-20
Filing date: 2007-03-30
Publication date: 2007-12-27
Anticipated expiration: 2027-03-30
Also published as: CN1929228A; GB0706293D0; CN100472908C; GB2439359B

Abstract

The present invention discloses a dual-magnetic control type high-sensitive leakage protector, which includes zero-sequence mutual inductor 1, test button 2, control circuit chip IC 4, silicon controlled rectifier 5 and stationary contact 9, reset button assembly, electromagnetic assembly and stationary magnet 14. The said the reset button assembly which is inserted in the slide of circuit board 3 includes the reset button 6, link 8, reset spring 7 and movable magnet 11. The said electromagnetic assembly is combined to form an integral and fixed on a conducting strip 17. The end of the said conducting strip 17 is connected with the control circuit and another end of the said strip is provided with a movable contact matching with the said stationary contact 9. Two ends of said armature 13 are opposite to stationary magnet 14 and movable magnet 11 respectively and the opposite faces of stationary magnet 14 and movable magnet 11 have same polarity. Coil 12 is designed in such a way that when it is energized armature 13 will have polarity opposite to that of the corresponding face of stationary magnet 14. The magnetic intensity of movable magnet 11 is higher than that of stationary magnet 14. The present invention has the advantages of rapid breaking, high breaking capacity, high trip force, reliable working and small size.

Description

A Dual-magnetic Control Type High-sensitive Leakage Protector

FIELD OF THE INVENTION

The invention relates to a leakage protector, especially a dual-magnetic control type high-reliable leakage protective socket to protect safety of person and electrical devices.

DESCRIPTION OF THE RELATED ART

With technical and scientific development, people increasingly require electrical devices of the leakage-protective function. Leakage protector greatly ensures personal safety and safety of properties such as electrical devices. However, for the leakage protectors currently used both home and abroad, their trip mechanisms have low tripping force, breaking capacity and tripping speed. In case of high contacting pressure of their contacts they are difficult to trip and even their coil and silicon controlled rectifier would be burnt out, while in case of low contacting pressure, though they are easy to trip, their contacts become hot and would be burnt out due to increased contact resistance. It is very difficult to make them easily trip and meanwhile keep high contacting pressure between their movable contact and stationary contact. In addition, the spring is liable to soften after becoming hot, which results in heating and deformation of the plastic casing and in turn damage of protector itself. During normal working of the available leakage protectors, the coil is under energized state and the trip mechanism would be rusted, seized or burnt out.

SUMMARY OF THE INVENTION

This invention will solve the technical problems above and provide a dual-magnetic control type high-sensitive leakage protector, which includes the followings: -zero-sequence mutual inductor, test button, control circuit chip IC, silicon controlled rectifier and stationary contact fixed in the circuit board; -reset button assembly inserted in the slide of circuit board; -electromagnetic assembly consisting of coil, skeleton and armature; and -stationary magnet fixed in the casing.

the said the reset button assembly includes the reset button, link, reset spring and movable magnet; the bottom of the said reset button is fitted with a link and the upper sleeve of the said link is fixed with a reset spring and another end of the link is fitted with a movable magnet, the said electromagnetic assembly is combined to form an integral and fixed on a conducting strip, the end of the said conducting strip is connected with the control circuit and another end of the said strip is provided with a movable contact matching with the said stationary contact, two ends of said armature are opposite to stationary magnet and movable magnet respectively and the opposite faces of stationary magnet and movable magnet have same polarity, coil is designed in such a way that when it is energized armature will have polarity opposite to that of the corresponding face of stationary magnet, the magnetic intensity of movable magnet is higher than that of stationary magnet.

The present invention a dual-magnetic control type high-sensitive leakage protector, makes use of the tired contacting pressure of the said two magnets, and the space between the magnet and armature is getting less, the said contacting pressure more, withal the contacting pressure has a tendency to unfailing. In case of leakage, magnetic field which is produced with the said coil and armature, is repelled with the movable magnet which has the same electric charges, and attracted with the stationary magnet which has the different one. It is break so fast when the repellency and attraction occurred at the same time, and the breaking time can be controlled within 1 0-3Oms, there has a great increasing of the reliability to protect safety of person and property. According to the present invention, because of no wearable parts in the protector, no wearing-out or slippage would occur, Its another advantage is that the trip mechanism renders the contact high contacting pressure and low contact resistance, is not liable to become hot, and has high breaking capacity and a tripping force twice that of common leakage protector. Hence it solves the above-mentioned technical problems and makes the high-sensitive leakage protector reliable and compact.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention shall be further described in combination with the implementation examples.

Fig 1 is a schematic drawing showing the structure of this invention.

Fig 2 is the bottom view of Fig 1.

Fig 3 is the top-view of Fig 1.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the Figs, the dual-magnetic control type high-sensitive leakage protector involved in this invention includes: -zero-sequence mutual inductor 1, test button 2, control circuit chip IC 4, silicon controlled rectifier 5 and stationary contact 9 fixed in the circuit board 3; -reset button assembly inserted in the slide of circuit board 3; -electromagnetic assembly consisting of coil 12, skeleton 15 and armature 13; and -stationary magnet 14 fixed in the casing.

The said reset button assembly includes reset button 6, link 8, reset spring 7 and movable magnet 11. The bottom of the said reset button 6 is fixed with link 8 and the upper sleeve of the said link 8 is fixed with a reset spring 7 and another end of the link is fitted with movable magnet 11.

The said electromagnetic assembly is combined to form an integral and riveted onto conducting strip 17 through epoxy plate. The residual distance of the interval between circuit board 3 and casing less the length of armature 13 is 3-4mm, which is just the travel of the electromagnetic assembly and suitable for the breaking distance specified for AC25OV voltage. Coil 12 is connected with the control circuit through conductor 16.

One end of the said conducting strip 17 is through zero-sequence mutual inductor connected with the control circuit and the power wire and another end of the said strip is provided with movable contact 10 matching with the said stationary contact 9.

Stationary contact 9 is connected with the plug-conductor of the leakage-protective socket. Two ends of said armature 13 are opposite to stationary magnet 14 and mQvable magnet 11 respectively. The opposite faces of the said stationary magnet 14 and movable magnet 11 have same polarity, (i.e. N pole to N pole or S pole to S pole).

When coil 12 is applied with DC, armature 13 will be repelled from the attracted magnet to another magnet.

The said coil 12 is designed in such a way that when it is energized armature 13 will have polarity opposite to that of the corresponding face of stationary magnet 14 and thus in case of leakage in the circuit the electromagnetic assembly will be attracted to stationary magnet 14 so as to separate movable contact 10 from stationary contact 9.

The magnetic intensity of movable magnet 11 shall be higher than that of stationary magnet 14, which after pressing the reset button will turn electromagnetic assembly from the state attracted by stationary magnet 14 to the state attracted by movable magnet 11. Under action of resilience of reset spring 7, movable contact 10 will contact with stationary contact 9 to reach a reset state.

The dual-magnetic control type high-sensitive leakage protector of this invention works under the following principle: Once the reset button is pressed the circuit is turned on and when the test button is pressed the circuit is turned off. If the reset button is pressed on while the leakage in the circuit is yet not eliminated, the dual-magnetic control type high-sensitive leakage protector will be still able to immediately cut off the circuit during its resetting process so as to protect safety of person and property.

I. Energizing When the dual-magnetic control type high-sensitive leakage protector is connected 22OVAC power supply, after pressing reset button 6 strong movable magnet 11 will approach armature 13, the resilience generated by reset spring 7 will pull armature 13 from the stationary weak magnet, and meanwhile the coil skeleton fixed in the armature, integral-connected conducting strip 17, movable contact 10 and stationary contact 9 will rest and thus energizing is completed.

II. Breaking In case of leakage, the zero-sequence mutual inductorl will sense the leakage signal, and amplification, comparison and conversion by 1C4 the foot of IC 5 will output high level to trigger silicon controlled rectifier 5 to feed unidirectional current to coil 12.

Thereby, armature 13 repels from strong movable magnet 11 and meanwhile attracts stationary weak magnet 1 4 due to opposite polarities and thus the power source is cut off. When the test button is pressed, the circuit works in the same way to cut off the power source.

The protector works repeatedly in this way. The leakage protector of this invention is characterized by low cost, reliable function and long service life.

It shall be understood that the embodiments above are merely explanation to but is not restriction of this invention. Any invention within the substantive features herein shall be under protection range of this invention.

Claims

Claims 1. A Dual-magnetic Control type high-sensitive leakage

protector, which includes: -zero-sequence mutual inductor (1), test button (2), control circuit chip IC (4), silicon controlled rectifier (5) and stationary contact (9) fixed in the circuit board (3); -reset button assembly inserted in the slide of circuit board (3); -electromagnetic assembly consisting of coil (12), skeleton (15) and armature (13); and -stationary magnet (14) fixed in the casing; characterized in that the said reset button assembly includes reset button (6), link (8), reset spring (7) and movable magnet (11); the bottom of the said reset button (6) is fixed with link (8) and the upper sleeve of the link (8) is fixed with a reset spring (7) and another end of the link is fitted with movable magnet (11), the said electromagnetic assembly is combined to form an integral and fixed onto conducting strip (17), one end of the said conducting strip (17) is connected with the control circuit and another end of the said strip is provided with movable contact (10) matching with the stationary contact (9), two ends of said armature (13) are opposite to stationary magnet (14) and movable magnet (11) respectively and the opposite faces of stationary magnet (14) and movable magnet (11) have same polarity, coil (12) is designed in such a way that when it is energized armature (13) will have polarity opposite to that of the corresponding face of stationary magnet (14), the magnetic intensity of movable magnet (11) is higher than that of stationary magnet (14).

2. The dual-magnetic control type high-sensitive leakage protector according to claim 1, wherein the said electromagnetic assembly is riveted onto conducting strip (17) through epoxy plate.

3. The dual-magnetic control type high-sensitive leakage protector according to claim 1, wherein the working travel of the said electromagnetic assembly is 3-4 mm.

4. A leakage protector for a device connected to a power supply, the leakage protector comprising: a first magnet (11); a second magnet (14); an armature (13) positioned in between the first magnet and the second magnet, the armature having a coil wound around it; and means for detecting current leakage (1); wherein the armature has a first position in the absence of current in the coil, where the armature is attracted to the first magnet, the first position maintaining the connection between the device and the power supply, wherein the armature has a second position, in the presence of current in the coil, where the armature is attracted to the second magnet, the second position breaking the connection between the device and power supply, and wherein, in operation, if current leakage is detected, the detecting means causes current to flow in the coil such that the armature changes from the first position to the second position.

5. A leakage protector substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 3 of the accompanying drawings.