CN2178956Y

CN2178956Y - Safety device for electrical equipment of household

Info

Publication number: CN2178956Y
Application number: CN 93232931
Authority: CN
Inventors: 董方秘
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-12-27
Filing date: 1993-12-27
Publication date: 1994-10-05
Anticipated expiration: 2003-12-27

Abstract

The utility model discloses a safety device for household electrical appliances, which relates to a power protection switch capable of both over-voltage protection and over-current protection. The utility model is a household electrical appliance protecting device with a relay, and is composed of an intermediate relay, a detecting transformer, a switch circuit, an alarm circuit and a lightning protection circuit. The detecting transformer is provided with three stages of coils, L1, L2 and L3. When the power supply is off-normal, the induction voltage of L3 rises, causing an electronic switch to switch on and the relay to operate, which not only cuts off the power supply, but also switches on the power supply of the alarm circuit to emit alarm sound. The lightning protection circuit has two groups: one group is to connect two voltage-sensitive resistors in parallel with the output terminal of the power supply, and the other group is to connect three voltage-sensitive resistors in parallel with the both ends of L3. When household electrical appliances are attacked by lightning, the surge voltage is released through the voltage-sensitive resistors.

Description

Safety device for electrical equipment of household

The utility model relates to the power protection switch that a kind of overvoltage, overcurrent can both be moved, protection household electricity safety.

Existing Protector for using electricity such as CN2086003U " Means for indicating condition of fuse " mainly are made up of current-limiting resistance, light-emitting diode, fuse and piezoelectricity singing piece, and light-emitting diode and piezo parallel connection are connected with current-limiting resistance then.This device short circuit that is insured at ordinary times, voltage is added in the load, once blown fuse, voltage is added in warning circuit, sends sound, light is reported to the police.Every warning once, fuse is also scrapped, and need to change a fuse, and it is blunt to report to the police, as long as fuse does not blow then and do not report to the police.

The purpose of this utility model is to provide a kind of household electrical appliance protector that has relay, for overvoltage with cross the protective device that ripple can both move.

Referring to Fig. 1, the utility model electrical schematic diagram.The utility model comprises auxiliary relay, detects transformer, electronic switch, warning circuit and lightning protection circuit.Its course of work is as follows:

220 volts of L1 coils through auxiliary relay J1 normally closed contact and detection transformer BT1 of civil power supply household electrical appliance.At ordinary times, the coil-induced voltage of L3 is lower, the electronic switch conducting that triode BG1, BG2 are formed.In case supply voltage raises, the last induced voltage of L3 also increases, make the voltage that is added on BG1, the BG2 raise, make BG1, BG2 conducting, i.e. electronic switch action, relay J 2 adhesives, J2-1 normal opened contact closure, connect warning circuit, power supply gives sounding integrated IC power supply through resistance step-down, diode full-wave rectification, the IC warning of sounding.Because J2-1 junction closure, make relay J 1 adhesive, the commutation of J1-1 contact, disconnect with contact a, the power supply of cutting off the electricity supply, the J1-1 contact is connected with contact b, power supply is delivered to detection transformer L1 coil, make L3 respond to output HIGH voltage once more, guarantee electronic switch BG1, BG2 conducting, relay J 2 keeps attracting state constant.

Overcurrent protection is similar to overvoltage protection, increases suddenly by the L1 coil current, overloads; the coil-induced high voltage of L3; make the electronic switch conducting, make relay J 2 adhesives equally, J2-1 normal opened contact closure; connect warning circuit; relay J 1 adhesive, the commutation of J1-1 contact, the power supply of cutting off the electricity supply; also power supply is delivered to simultaneously and detected transformer L2 coil, the L3 coil is responded to high voltage once more makes relay J 2 keep adhesive.

Lightning protection circuit has two groups, and one group is that surge voltage is released by piezo-resistance when being struck by lightning at power output end and di-piezo-resistance R5, R6.One group is connected in parallel on the magnetic test coil L1, i.e. power input, and shared three piezo-resistance R7～R9, when being struck by lightning, surge voltage is released by piezo-resistance.

State the annexation of chatting each parts below in conjunction with accompanying drawing.

Fig. 1 the utility model circuit theory diagrams.

Fig. 2 detects the transformer device structure schematic diagram.

Referring to Fig. 1, the utility model household electrical appliance protector, comprise fuse BX, it is characterized in that also comprising auxiliary relay J1, detect transformer BT, switching circuit, warning circuit and lightning protection circuit, civil power is connected with the primary coil L1 that detects transformer BT through fuse Bx, auxiliary relay J1 normally closed contact a, the other end of L1 connects household electrical appliance, wherein:

Switching circuit is by diode D1～D4, rectification circuit and capacitor C 2 that capacitor C 1 is formed, C3, resistance R 1, diode D5, D6, relay J 2 and transistor BG1, BG2 forms, D1～D4 forms bridge rectifier, its output negative pole meets C1, R1, D6, the coil of C3 and J2, positive pole meets C1, C2, the other end of C3 and BG1, the emitter of BG2, the end of another termination voltage stabilizing didoe D5 of R1, the other end of D5 connects the negative terminal of C2 and the base stage of BG1, the emitter of BG1 is connected with the base stage of BG2, the collector electrode of BG1 is connected with the collector electrode of BG2, goes back simultaneously and D6, the J2 coil links to each other;

Warning circuit is by R2, the reduction voltage circuit that C4 composes in parallel and D7～D10, bridge rectifier filter circuit and integrated IC of sounding that C5～C9 forms, R3, R4, BG3 and loud speaker YD form, civil power is through J2-1 contact and R2, C4 one end links to each other, R2, the other end of C4 and rectifier diode D7, D8, filter capacitor C5, C6 connects, the rectification output negative pole connects C9, C10, the end of D11, IC the 1st, 6 pin and loud speaker YD, the anodal C9 that connects, C10, the other end of D11, the 4th pin of the emitter of BG3 and IC, resistance R 3 is serially connected in the 2nd of IC, between 3 pin, the end of the 5th pin output termination R4 of IC, the other end of R4 connects the base stage of BG3, and the collector of BG3 is connected with loud speaker YD;

Lightning protection circuit has two groups, one group is at power output end and di-piezo-resistance R5, R6, another group is attempted by between contact b and the power input by piezo-resistance R7, R8 series connection back and R9, tie point and the ground wire of R7, R8 join, and also are serially connected with the displacement K switch between contact b and detection transformer L1.

In addition, among the embodiment, also be provided with indicating circuit, comprise the work indication that composes in series by current-limiting resistance R10 and indicator light ZD1, be connected in parallel on power output end at L1 and power input; By the warning indication that current-limiting resistance R11 and indicator light ZD2 compose in series, be connected in parallel on and detect on the transformer secondary output coil L2.

Among the embodiment, in order to adjust switching circuit, L3 is provided with 4～8 taps at detection transformer secondary output coil, is used to adjust the protection range of switching circuit, by selector switch K2, makes it to be connected with rectification circuit input end diode D1, D2.

Referring to Fig. 2, among the embodiment, detect transformer and select C type ferrite high frequency magnetic core for use, L1, L2, L3 all are wound on the circular coil holder, and the coil holder of L3 is enclosed within the coil holder of L1.L1 is that 110 circles, L2 are that 8500 circles, L3 are 500～3000 circles.

Integrated of sounding is selected KD9564 for use, and piezo-resistance is selected MYL3-300V for use, and reset switch K selects for use push-button switch, selector switch K2 to select the hilted broadsword band switch for use.

Claims

1, a kind of household electrical appliance protector, comprise fuse BX, it is characterized in that also comprising auxiliary relay J1, detect transformer BT, switching circuit, warning circuit and lightning protection circuit, civil power is connected with the primary coil L1 that detects transformer BT through fuse Bx, auxiliary relay J1 normally closed contact a, the other end of L1 connects household electrical appliance, wherein:

2, by the described household electrical appliance protector of claim 1, it is characterized in that also being provided with indicating circuit, comprise the work indication that composes in series by current-limiting resistance R10 and indicator light ZD1, be connected in parallel on power output end at L1 and power input; By the warning indication that current-limiting resistance R11 and indicator light ZD2 compose in series, be connected in parallel on and detect on the transformer secondary output coil L2.

3, by the described family expenses protector of claim 1; it is characterized in that being provided with 4～8 taps at detection transformer secondary output coil L3; be used to adjust the protection range of switching circuit,, make it to be connected with rectification circuit input end diode D1, D2 by selector switch K2.