CN2375021Y

CN2375021Y - Overvoltage safety protector for electrical appliances

Info

Publication number: CN2375021Y
Application number: CN 99231723
Authority: CN
Inventors: 董世荣
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-05-28
Filing date: 1999-05-28
Publication date: 2000-04-19
Anticipated expiration: 2009-05-28

Abstract

The utility model relates to an overvoltage safety protector for electrical appliances, which has two kinds of protection, commercial power overvoltage of sub appliances and stable power supply overvoltage of appliance switches. The utility model has the structure that an overvoltage protecting circuit which is composed of error signal detection, error signal processing and an actuator or an overvoltage protecting circuit which is only composed of the error signal detection and the actuator is arranged on a circuit board, and two pairs or one pair of earth connection terminals connected with an appliance are arranged on the circuit board. The utility model has the advantages of simple structure, high reliability and strong practicability, and is suitable for the protection of domestic electrical appliances. The utility model is particularly suitable for the safety protection of colour televisions, and can effectively prevent the colour televisions from unsafe incipient faults of kinescope breakdown and explosion, because of the overvoltage of commercial power and built-in switch stable voltage power supply.

Description

Electric equipment overvoltage safety protection device

The utility model relates to a kind of electric equipment overvoltage safety protection device of electronic technology field, and it is applied to the household electrical appliance protection, especially is adapted to color television set is carried out safeguard protection.

According to the knowledge of the applicant, on various medium, see the news report that the picture tube of colour TV is blasted repeatly, then be more common in homemade colour TV.Trace it to its cause, except that the quality of picture tube own, principal element has: 1, the colour TV rated operational voltage is 220V, but the user who has is nearer from power transformer, and voltage has reached 250V, in case the electrical network load lightens, voltage is superpressure more.Owing to most local power line of China and civil power common zero line, if zero line fracture or zero line contact resistance increase, all can cause line voltage to rise, again often above 260V even up to more than the 380V.So high civil power not only may damage the electronic devices and components of colour TV, and the suffered high pressure of picture tube is raise, and is easy to meet accident.2, colour TV is that the 220V civil power is output as 115V (or 130V or 145V) by the switching power supply adjustment after being rectified into 300V left and right sides pulsating direct current electric current, boosts to about 30KV through high voltage package to be added on the picture tube again.Out of control when the colour TV Switching Power Supply, if be raised to 200V, the added voltage of picture tube can reach 50KV by the 115V of switching power supply adjustment output, and so high voltage is added to picture tube, just might cause that picture tube punctures, even explode.Since described factor, and most of now colour TV does not add over-pressure safety device, exists the hidden danger that people see TV.

The purpose of this utility model is intended to from the purpose of protection electric equipment; avoid color television set because of civil power superpressure or the internal electric source own above-mentioned drawback due to being out of order effectively; the applicant keeps in repair the practical experience of television set during the last ten years according to oneself, has designed a kind of simple in structure, practical electric equipment overvoltage safety protection device (also claiming colour TV overvoltage safety protection device).This protector is applied to colour TV, can eliminate people fully and see the hidden danger of TV because of voltage problem.

The purpose of this utility model is to realize with such technical scheme: subset mains supply over-voltage and two kinds of protectors of facility switching stabilized voltage power supply overvoltage.Its structure is at wiring board (also claiming components and parts that connecting plate is installed) mains supply over-voltage protective circuit or switching power supply overvoltage crowbar to be installed, and wiring board is provided with two pair of wire connection terminals or pair of terminals that links to each other with equipment.

In housing, be provided with the mains supply over-voltage protective circuit; be provided with in the circuit board to stretch and put outer two pair of wire connection terminals of housing as civil power input and civil power output after protective circuit; this protective circuit comprises that error signal detection, error signal processor, executive component constitute; the input that its electric resistance partial pressure detects is imported two binding posts with the civil power on the wiring board and is linked to each other, and the executive component output is exported two binding posts with the civil power on the wiring board and linked to each other.In equipment, use this protector; after line voltage surpasses certain voltage value; through electric resistance partial pressure error signal is detected; make the work of error signal processor; promote the executive component fill order; the mains supply of cut-out equipment (promptly forcing the input of civil power and equipment to disconnect) reaches the purpose of protecting electric equipment.

Above-mentioned error signal processor is to adopt components and parts such as computing amplifier integrated block, time-base circuit integrated package, controllable silicon (single, double to all can), triode, field effect transistor, optoelectronic switch, digital circuit integrated package wherein any and the circuits for triggering of peripheral cell formation.

Above-mentioned executive component adopts a kind of in controllable silicon (single, double to controllable silicon all can), the relay, and relay can be common relay or switch combination relay or motor relay switch etc.

Circuits for triggering comprise a kind of in voltage stabilizing didoe, diac, thyristor, the neon tube.

When executive component adopted one-way SCR, the mains supply over-voltage protective circuit was set up polarity switch.

Be provided with colour TV switching power supply overvoltage safety protection circuit in housing, be provided with in the circuit board to stretch and put outer pair of terminals of housing, this protective circuit is detected by error voltage and executive component constitutes.This error voltage detects to electric resistance partial pressure detects, executive component employing controllable silicon (single, double to all can) components and parts, and the controllable silicon output links to each other with the voltage end of binding post.In equipment, use this protector, when facility switching power supply output voltage surpasses certain value, be in short-circuit condition immediately,, shake a little less than making it the switching power supply short circuit, thus the protection electric equipment.Have only fault to get rid of, just recover normal operation.This switching power supply overvoltage safety protection device is applied in the colour TV, because this protector is directly controlled colour TV line-scan circuit principal voltage, output signal does not go to control the colour TV other parts again, so reliability increases substantially.

Binding post on the wiring board can be located on the housing.

If the bodily form of protector is little, can be made into modular form.

Protector also can not established housing, and the wiring board that installs the protective circuit element is directly installed in the electric equipment.

The utlity model has characteristics such as simple in structure, that cost is low, reliability is high, making is easy.Also owing to be the integral piece of individual packages, it and other circuit onrelevant of electric equipment (particularly colour TV), install additional as easy as rolling off a log.This protector only needs circuit element parameter is made appropriate change according to the equipment requirements of being protected; just can be widely used in refrigerator, air conditioner, washing machine, video disc player household electrical appliance and other machinery equipment etc., reach the safeguard protection purpose of the switching power supply overvoltage of electric equipment mains supply over-voltage and electric equipment own.

Below in conjunction with accompanying drawing the utility model embodiment is described in further detail:

Fig. 1 is a kind of structural representation block diagram of the utility model colour TV mains supply over-voltage protector.

Fig. 2 is the another kind of structural representation block diagram of the utility model colour TV mains supply over-voltage protector.

Several circuit theory diagrams that Fig. 3-Fig. 9 is adopted for square frame part among Fig. 1.

A kind of circuit theory diagrams that Figure 10 is adopted for square frame part among Fig. 2.

Figure 11 is the structural representation block diagram of the utility model colour TV Switching Power Supply overvoltage safety protection device.

The circuit theory diagrams that Figure 12 is adopted for square frame part among Figure 11.

The circuit theory diagrams that Figure 13 is also adopted for square frame part among Fig. 1.

Embodiment one: referring to Fig. 1, Fig. 3.This civil power overvoltage safety protection device comprises housing 1, wiring board (2,2 '), binding post (3,3 ' and 4,4 ') and detects the protective circuit that A, error signal processor B, executive component C three parts constitute by error signal.Its two pair of wire connection terminals (3,3 ' with 4,4 ') is located at respectively on the wiring board (2,2 '); Each components and parts of protective circuit are installed on wiring board 2,2 ' (can be the printed substrate or the insulation board of plus interconnect line); Outside installing the wiring board of components and parts, install housing 1 additional.Its protective circuit: error signal detects A and is detected by the electric resistance partial pressure that resistance R 1 or potentiometer (10-100K Ω), resistance R 2 (200K Ω) and capacitor C 1, diode D1 constitute; Detect the diode that has been connected with trigger action between output and the error signal amplification processor input in error signal, the error signal processor B is that (resistance R 3, R4 dividing potential drop are as the reference voltage of integrated package F by voltage stabilizing didoe W1, computing amplifier integrated block F and peripheral cell, voltage-stabiliser tube W2 is as the stable reference voltage of integrated package F, capacitor C 2 is used to prevent disturb) the triggering amplifying circuit that constitutes, if required precision not high voltage stability diode W1 save, with lead with its short circuit; Executive component C adopts bidirectional triode thyristor BT; The operating voltage VD (5-30V) that supplies with integrated package F obtains the civil power that binding post (3,3 ') is imported through transformer step-down → rectification → filtering.Circuit working principle: when behind binding post (3,3 ') input civil power, through resistance R 1, resistance R 2 dividing potential drops, the a point voltage is risen with line voltage, when line voltage is too high (colour TV reaches 270V), voltage stabilizing didoe W1 punctures, the input terminal voltage of computing amplifier integrated block F is risen, and the output voltage of computing amplifier integrated block F is 0V.At this moment, bidirectional triode thyristor BT triggerless voltage and ending plays the effect of protection colour TV.When civil power just often because voltage-stabiliser tube W1 do not puncture, the output current of computing amplifier integrated block F triggers bidirectional triode thyristor BT through resistance R 6 restriction backs and makes its conducting, thus output (4,4 ') has civil power output, colour TV has the voltage supply.

Referring to Fig. 1, Fig. 4, different with the foregoing description one is: the error signal processor B is to be made of time-base circuit ic chip and peripheral cell (drawing among the figure), and the operating voltage VD of ic chip (5-30V) is provided by circuit in the frame of broken lines (transformer step-down → rectification → filtering); Executive component C adopts relay J; Other structure is with embodiment one.Circuit working principle: rise with line voltage; through potentiometer R1, resistance R 2 dividing potential drops; make a point voltage with line voltage rising 270V when above; voltage stabilizing didoe W punctures; input (2, the 6 pin) voltage of ic chip is risen, the output of ic chip output (3 pin) no current, relay discharges the contact K that causes relay J and disconnects; disconnect the civil power of colour TV, play the effect of protection colour TV.

Referring to Fig. 1, Fig. 5, different with the foregoing description one is: the error signal processor B is the triggering amplifying circuit that is made of voltage stabilizing didoe W and one-way SCR T, and the operating voltage of one-way SCR T is provided by diode D1, capacitor C 1 rectification; Executive component C adopts relay J; Other structure is with embodiment one.The circuit working principle: when line voltage surpasses 270V, make a point voltage liter by potentiometer R1, resistance R 2 dividing potential drops, voltage stabilizing didoe W is breakdown; trigger one-way SCR T conducting; cause the relay J adhesive, the contact K of relay J is disconnected, disconnect the civil power of colour TV, play the effect of protection colour TV.

Referring to Fig. 1, Fig. 6, different with the foregoing description one is: the error signal processor B is the triggering amplifying circuit that is made of voltage stabilizing didoe W and triode BG, and the operating voltage of triode BG is provided by diode D1, capacitor C 1 rectification charging; Executive component C adopts relay J; Other structure is with embodiment one.Circuit working principle: when line voltage surpasses 270V, make a point voltage liter, puncture voltage stabilizing didoe W by potentiometer R1, resistance R 2 dividing potential drops; make triode BG have electric current to flow through; the contact K that make the relay J adhesive, causes relay J disconnects, and disconnects the civil power of colour TV, plays the effect of protection colour TV.

Referring to Fig. 1, Fig. 7, different with the foregoing description one is: the error signal processor B is the triggering amplifying circuit that is made of voltage stabilizing didoe W and triode BG, and the operating voltage of triode BG is provided by two utmost point D1, capacitor C 1 rectification; Executive component C adopts bidirectional triode thyristor BT; Other structure is with embodiment one.The circuit working principle: when line voltage surpasses 270V, potentiometer R1, resistance R 2 dividing potential drops make a point voltage liter, and voltage stabilizing didoe W is breakdown; triode BG is saturated, and the b point voltage is below the 1V, the resistance R no current; bidirectional triode thyristor BT triggerless electric current and turn-offing plays the effect of protection colour TV.

Referring to Fig. 1, Fig. 8, different with the foregoing description one is: the triggering ghyristor circuit that the error signal processor B is made of voltage stabilizing didoe W and one-way SCR T, and the operating voltage of one-way SCR T is provided by diode D1, capacitor C 1 rectification; Executive component C adopts bidirectional triode thyristor BT; Other structure is with embodiment one.The circuit working principle: when line voltage surpasses 270V, by potentiometer R1, resistance R 2 dividing potential drops a point voltage is risen, voltage stabilizing didoe W is breakdown; trigger one-way SCR T conducting, the b point voltage is descended; cause the BT triggerless and close and continue, thereby disconnect the civil power of colour TV, play the effect of protection colour TV.

Referring to Fig. 1, Fig. 9, different with the foregoing description one is: the error signal processor B is the circuits for triggering that are made of voltage stabilizing didoe W and time-base circuit ic chip and peripheral cell (drawing among the figure); Executive component C adopts bidirectional triode thyristor BT; The operating voltage of time-base circuit ic chip (5-24V) is provided by circuit in the frame of broken lines (transformer step-down → rectification → filtering); Other structure is with embodiment one.Circuit working principle: when civil power surpasses 270V; by potentiometer R1, resistance R 2 dividing potential drops a point voltage is risen; voltage stabilizing didoe W punctures; the input terminal voltage of ic chip is risen; the integrated package I output no-output electric current R that flows through removes to trigger controllable silicon BT; turn off because of controllable silicon BT triggerless electric current, played the effect of protection colour TV.

Embodiment two: referring to Fig. 2, Figure 10: this civil power overvoltage safety protection device comprises housing 1, wiring board 2, binding post (3,3 ' and 4,4 ') and detects the protective circuit that A, error signal treatments B, executive component C, polarity switch D constitute by error signal.Two pair of wire connection terminals (3,3 ' and 4,4 ') be located on the wiring board 2; The error signal processor B is the triggering ghyristor circuit that is made of diac W and bidirectional triode thyristor T.The operating voltage of controllable silicon T is provided by resistance R 3; Executive component C adopts one-way SCR BT; Because of executive component adopts one-way SCR, should establish polarity switch D (as adopting rectifier bridge heap etc.); Other structure is with embodiment one.Circuit working principle: when line voltage surpasses 270V; make a point voltage liter by potentiometer R1, resistance R 2 dividing potential drops; diode W punctures; bidirectional triode thyristor T is triggered and conducting; cause the b point voltage to drop to below the 1V, the no current R that flows through removes to trigger controllable silicon BT, and BT is turn-offed; make binding post (4,4 ') no-voltage, play the effect of protection colour TV.

Embodiment three: referring to Figure 11, Figure 12, this Switching Power Supply overvoltage safety protection device comprises housing 1, wiring board (2,2 '), binding post (5,5 ') and the colour TV Switching Power Supply overvoltage safety protection circuit that is made of error signal detection A, executive component C.Its binding post (5,5 ') is located on the wiring board (2,2 '); It (can be on the printed substrate or the insulation board of plus interconnect line that each components and parts of protective circuit are installed in wiring board 2; Add housing 1 at the wiring board 2 that installs components and parts.Error signal detects A and is detected by the electric resistance partial pressure that resistance R 1 or potentiometer (10-50K Ω), resistance R 2 (33K Ω) constitute; Executive component C is that the one or two-way controllable silicon also can.The operating voltage of circuit is decided according to the colour TV model; the operation principle of circuit is: resistance R 1 and resistance R 2 are sample resistance; R1 and R2 are divided into 80V left and right sides direct current; when colour TV switching power supply output voltage rises; R1; the branch pressure voltage of R2 rises thereupon; after the puncture voltage that reaches voltage stabilizing didoe W; the controllable silicon BT conducting that is triggered; controllable silicon BT is short-circuit condition, and (this moment is by controllable silicon BT electric current 0.2-0.3A, and undertension 1V, and controllable silicon BT power consumption is lower than 0.3W; as safe as a house); the colour TV switch transformer is secondary by short circuit, forces the colour TV Switching Power Supply to carry out weak vibration, has protected colour TV picture tube and other element effectively.Because the voltage stabilizing value height that voltage stabilizing didoe W selects, the 115V of colour TV Switching Power Supply output, even have only 10V to change, but the voltage that is reflected to branch pressure side a is at least the variable quantity of 5V, this variable is enough to puncture voltage stabilizing didoe W, makes controllable silicon BT conducting.

Embodiment four: referring to Fig. 1, Figure 13, it is to comprise housing 1, wiring board (2,2 '), binding post (3,3 ' and 4,4 ') and detect mains supply over-voltage, the under-voltage protecting circuit that A, error signal processor B, executive component C constitute by error signal.Detect as mains supply over-voltage by resistance R 1, R2 and bidirectional trigger diode W1; Resistance R 4, R3 and bidirectional trigger diode W2, bidirectional triode thyristor T2, diode D, bidirectional trigger diode W are as the under-voltage detection of civil power (all can set up this under-voltage detection) in above Fig. 3-Fig. 9 circuit; For protecting this circuit, set up one-way SCR T0, resistance R 0 as overcurrent protection; Other structure is still with embodiment one.The circuit working principle: when civil power is too high (more than 270V), resistance R 1, R2 dividing potential drop rise a point voltage, the bidirectional trigger diode W1 conducting that is triggered, and controllable silicon T1 is triggered and conducting, and the b point voltage is descended.R removes to trigger controllable silicon BT because no current is flowed through, and BT is turn-offed, and cuts off the colour TV civil power and supplies with, and plays a protective role.When civil power is under-voltage (as being lower than 100V), resistance R 4, R3 dividing potential drop descend a ' point voltage, make the bidirectional diode W2 that is in conducting state no longer breakdown, because of T2 triggerless electric current turn-offs, b ' voltage is risen, make the bidirectional diode W conducting that is triggered, controllable silicon T1 is triggered and conducting, and the b point voltage is descended.Controllable silicon BT triggerless voltage and turning off cuts off civil power and supplies with, and has reached protection.When civil power just often because T1 is not triggered, so the b point voltage rises.This moment, voltage triggered controllable silicon BT and conducting through resistance R, and electrical equipment gets electric work.

More than main component parameter select: single, double to controllable silicon require withstand voltage greater than 1000V, electric current greater than 15A, time-base circuit ic chip model is NE7555, NE555, NE556 etc., digital circuit integrated package model is as CD4001CD4069 etc., voltage stabilizing didoe requires voltage 50-100V, computing amplifier integrated block F model is LM324, LM358, LM3900 etc., and triode BG is withstand voltage greater than 400V, electric current greater than 1A.To be that flame-retardant materials, shape rectangle are cylindrical etc. all can the material of housing 1.Wiring board can be established one or a few, and binding post can be located on the housing (on the housing indicator light can be set).This protector can make module if whole volume is little.

This protector is applied in the colour TV (or miscellaneous equipment), power line is cut off binding post 3,3 ' link to each other with colour TV civil power end of incoming cables, binding post 4,4 ' link to each other with the mains electricity input end of colour TV.Two inputs and two outputs all non-directional (be binding post 3,3 ' and binding post 4,4 ' all is non-directional).

This protector is applied in the colour TV, binding post 5 is directly joined the ground end of 5 ' end and colour TV join (when installing additional, as far as possible being contained in 2 ends of main power source filter capacitor) with colour TV Switching Power Supply output (be principal voltage such as 115V, 130V, 145V all can).

Claims

1, a kind of electric equipment overvoltage safety protection device; comprise binding post, wiring board and the mains supply over-voltage protective circuit on it; it is characterized in that: be provided with two pair of wire connection terminals in the circuit board as civil power input and civil power output after protective circuit; the mains supply over-voltage protective circuit comprises error signal detection, error signal processor, executive component; the input that its electric resistance partial pressure detects links to each other with the civil power two input wires terminals on the wiring board, exports two binding posts at executive component output and the civil power on the wiring board and links to each other.

2, electric equipment overvoltage safety protection device according to claim 1; it is characterized in that: error signal processor adopting operational amplifier, controllable silicon, time-base circuit integrated package, digital circuit integrated package, triode, field effect transistor, optoelectronic switch be the circuits for triggering that constitute of any components and parts and peripheral cell wherein, and executive component adopts a kind of in controllable silicon, the relay.

3, electric equipment overvoltage safety protection device according to claim 2 is characterized in that: circuits for triggering comprise a kind of in voltage stabilizing didoe, diac, thyristor, the neon tube.

4, electric equipment overvoltage safety protection device according to claim 1 and 2 is characterized in that: executive component adopts one-way SCR, and the mains supply over-voltage protective circuit is set up polarity switch.

5, electric equipment overvoltage safety protection device according to claim 1; it is characterized in that: in the circuit board; be provided with pair of terminals; the device power supply (DPS) overvoltage crowbar of protective circuit for being made of electric resistance partial pressure detection and controllable silicon and diac, its controllable silicon output links to each other with the voltage end of binding post.

6, electric equipment overvoltage safety protection device according to claim 1 or 5, it is characterized in that: have housing outside the wiring board of protective circuit is housed, binding post stretches out outside the housing.

7, electric equipment overvoltage safety protection device according to claim 6, it is characterized in that: binding post is located on the housing.

8, electric equipment overvoltage safety protection device according to claim 4 is characterized in that: polarity switch is the rectifier bridge heap.