CN2045157U - Fully automatic comprehensive protective device for household appliances - Google Patents

Abstract

The utility model discloses a fully automatic comprehensive protective device for household appliances belonging to the technical field of electronic and electrician. The fully automatic comprehensive protective device for household appliances is composed of an integrated circuit, an inverter, an electric shock detector, an over-current detector, a current-down detector, an over-voltage detector, an under-voltage detector and a relay. The fully automatic comprehensive protective device for household appliances has various protection functions in a state of electric shock, over-current, electric blanket firing, over-voltage, under-voltage and moment power failure, and each protection function is automatic. The fully automatic comprehensive protective device for household appliances has the advantages of simple structure and low cost, and the fully automatic comprehensive protective device for household appliances can be widely used for the security protection of household appliances and the human body through other circuits.

Description

Fully automatic comprehensive protective device for household appliances

The utility model belongs to electronics and electrical technology field.

The protector for household electrical appliances product is a lot, has the electrical shock protection function as electric protective device, and some also has overcurrent protection function concurrently, and and for example the refrigerator protector has the defencive function of overvoltage, under-voltage, instant cut-off.Though electric protective device is suitable for a lot of electrical equipment, function is few, though the refrigerator protector has 3 kinds of functions, only is applicable to refrigerator because when energising to delay time and just connect appliances power source about 5 minutes, like this with regard to the use band fork-like farm tool used in ancient China of other kind of electrical equipment inconvenience.

The utility model is in order to overcome above-mentioned every the deficiencies in the prior art; made a kind of comprehensive protector; the advantage of above-mentioned technology is combined; and increased electric blanket protection on fire; make defencive function be increased to electric shock, overcurrent, on fire, overvoltage, under-voltage, instant cut-off, and every kind of protection all is to carry out automatically.

Fig. 1 is the utility model product shape figure.

Fig. 2 is a circuit diagram, and principle is as follows:

Power supply by K switch through B ₃Step-down, QL rectification, C ₉Filtering, R ₈, DW, C ₈Voltage stabilizing provides circuit a burning voltage.555 integrated circuit (IC) and R ₃, R ₇, C ₇Constitute monostable circuit, C ₆Be transient stability electric capacity, at this moment because of C ₆Both end voltage can not be suddenlyd change, C ₆Transient state is equivalent to short circuit, IC ₄The pin transient state is equivalent to ground connection, no matter 2 pin current potentials how, IC must not overturn, 3 pin output electronegative potential, relay indicating light LED ₁Bright, relay J adhesive, normally opened contact J ₁, J ₂Connect load.

Zero sequence current mutual inductor B ₂, C ₂, D ₃, R ₂Form the electric shock detector.D ₃R is passed through at two ends ₂With the voltage voltage stabilizing at 0.7V, if when not having electric shock signal, L ₃No alternating voltage, D ₃On direct voltage by C ₂Isolate, when electric shock signal, L ₃On alternating voltage and D ₃On the Voltage Series addition, pass through C ₂Be added on the emitter junction of inverter BG, at this moment BG becomes conducting by ending, and this detector circuit can reduce the requirement of zero sequence current mutual inductor to sensitivity.When the BG conducting, the IC2 pin becomes electronegative potential, and IC triggers upset, and 3 pin become high potential, relay indicating light LED ₁Go out protection indicator light LED ₂Bright, J discharges, J ₁, J ₂Disconnecting consumers.At this moment C ₇Charging, after 5 minutes, IC ₆Pin voltage is during to 2/3Vcc, and IC resets, and 3 pin become electronegative potential, J adhesive, J ₁, J ₂Connect load.If when at this moment again electric shock signal being arranged, J ₁, J ₂Disconnecting consumers forms the protection automatically of getting an electric shock once more.

Current transformer B ₁, W ₁Form over-current detector.When the load overcurrent, L ₂Voltage rises, W ₁Voltage also rises, isolating diode D ₂Forward conduction and rectification, the BG conducting, IC triggers upset, and 3 pin become high potential, and J discharges, J ₁, J ₂Disconnecting consumers.J after 5 minutes ₁, J ₂Connect load.If load at this moment or overcurrent, J ₁, J ₂Disconnecting consumers forms overcurrent and protects automatically once more.

Electric blanket reason on fire is because heating wire fractures, and the energising back switches on and off continuously at the place of fractureing, and has just produced continuously sparking, and these sparks are heated to the above temperature of material burning-point to plastics on every side and fabric, cause and catch fire.At this reason, this protective circuit has been set up a cutout detector, when heating wire has a cutout signal, just cuts off the electrothermal wire power immediately, eliminates the generation of continuously sparking.Cutout all can appear in frequent the shutoff with manual temperature control type electric blanket of temperature relay of considering the thermostatic type electric blanket when temperature adjustment; so protective circuit is in time-delay energized again after 5 minutes; such once there being the cutout signal to cut off the electricity supply; the energized again of delaying time after 5 minutes makes the heating wire place of fractureing temperature can high not influence the use of various electric blankets again.Current transformer B ₁, D ₁, W ₂, D ₈Form the cutout detector.When cutout, L ₂No-voltage, W ₂No-voltage, D ₆Forward conduction triggers the IC2 pin, the IC upset, and 3 pin become high potential, and J discharges, J ₁, J ₂Disconnecting consumers is at this moment because of IC3 pin current potential is higher than 2 pin current potentials, so 3 pin high potentials pass through D ₇Be added to D ₆Negative pole makes D ₆Oppositely end, avoided IC is produced locking, IC can be resetted, so claim D ₇Be D ₈Back biased diode.After 5 minutes, J ₁, J ₂Connect load, if still cutout at this moment, J ₁, J ₂Disconnecting consumers forms automatic protection on fire once more.

W ₃It is overvoltage detector.When the line voltage height arrives 245V, there is not the rectifier power source voltage of voltage stabilizing to rise W ₃Voltage rises, isolating diode D ₄Forward conduction, the BG conducting, IC triggers upset, and 3 pin become high potential, and J discharges, J ₁, J ₂Disconnecting consumers till normal to line voltage, form overvoltage and protects automatically.

W ₄It is undervoltage detector.When line voltage hangs down to 180V, W ₄Voltage descends, isolating diode D ₆Forward conduction, the IC2 pin becomes electronegative potential, the IC upset, 3 pin become high potential, and J discharges, J ₁, J ₂Disconnecting consumers till normal to line voltage, forms under-voltage automatic protection.

When grid cut-off, C ₆Pass through R ₆, D ₉, R ₂, D ₃The discharge loop discharge that constitutes is because D ₉Backward resistance is big, so discharge was just put in very slow 5 minutes.C ₅Pass through R ₃, R ₂, D ₃With D ₆, W ₄With D ₆, W ₂Parallel circuits discharge, put immediately, if when power-off time was sent a telegram here again less than 5 minutes, because of C ₅Both end voltage can not be suddenlyd change, C ₅Moment is equivalent to short circuit, has triggered the IC2 pin, at this moment C ₆Voltage has not been put, IC ₄Pin voltage is greater than 0, and IC overturns, and 3 pin are high potentials, J no-voltage, J ₁, J ₂Disconnect load, form the instant cut-off delay protection.When if power-off time was sent a telegram here again greater than 5 minutes, C at this moment ₆Voltage has all been put, C ₆Transient state is equivalent to short circuit, and the IC4 pin is equivalent to ground connection, and IC must not overturn, J adhesive, J ₁, J ₂Connect load.

The utility model is owing to there is above-mentioned formation; institute is so that a functional multipurpose; can both protect automatically human body safety and security appliance; and circuit is simple; with low cost; and have and manually stop to protect button and electric shock test button, use conveniently, reliable, can be widely used in household electrical appliance and other electrical equipment.

Fig. 1 explanation: (1) shell (2) attaching plug (3) mains switch (4) indicator light (5) protects manual stop button (6) electric shock test button (7) to produce socket.

Fig. 2 explanation: R ₁Be simulation electric shock resistance, AN ₁Be electric shock test button, C ₁, C ₅Be anti-interference capacitor, C ₃, C ₄For moment is stablized electric capacity, D ₃Be fly-wheel diode R ₄, R ₅Be current-limiting resistance, AN ₂For protecting manual stop button.

Claims (3)

1, the full-automatic comprehensive protection device of a kind of household electrical appliance; its electronic circuit mainly is made of monostable circuit and inverter, zero sequence current mutual inductor, current transformer, overvoltage/undervoltage detector, relay and the stabilized voltage power supply that 555 integrated circuits are formed, and the input that is characterised in that described inverter BG of the present utility model and one are by capacitor C ₂, zero sequence current mutual inductor B ₂, diode D ₃, resistance R ₂The electric shock detector of forming links to each other, and has increased isolating diode D between over-current detector and the overvoltage detector respectively ₂, D ₄, the input of 555 integrated circuit (IC) and a diode D ₆Adjustable resistance W ₂Diode D ₁, current transformer B ₁The cutout detector of forming links to each other, and has increased isolating diode D between the undervoltage detector ₅

2, a kind of as the full-automatic comprehensive protection device of claim 1 described household electrical appliance, it is characterized in that the output of described 555 integrated circuit (IC) and stop having increased diode D between the detector ₆Back biased diode D ₇

3, a kind of as the full-automatic comprehensive protection device of claim 1 described household electrical appliance, it is characterized in that having increased the transient stability capacitor C between 4 pin of described 555 integrated circuit (IC) and the ground ₆, and increased resistance R between 8 pin ₆With diode D ₉Series circuit.

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