CN201191928Y - Temperature protection equipment for wire disc of electromagnetic furnace - Google Patents
Temperature protection equipment for wire disc of electromagnetic furnace Download PDFInfo
- Publication number
- CN201191928Y CN201191928Y CNU2008200838305U CN200820083830U CN201191928Y CN 201191928 Y CN201191928 Y CN 201191928Y CN U2008200838305 U CNU2008200838305 U CN U2008200838305U CN 200820083830 U CN200820083830 U CN 200820083830U CN 201191928 Y CN201191928 Y CN 201191928Y
- Authority
- CN
- China
- Prior art keywords
- resistance
- thermistor
- comparator
- wire coil
- ic4b
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Control Of Resistance Heating (AREA)
Abstract
The utility model relates to an induction cooker wire coil temperature protection device, which comprises a heating control circuit and a thermistor RT, wherein the heating control circuit is used to connect or cut wire coil power supply according to control signals, and the thermistor RT is used to detect the temperature of a wire coil. The induction cooker wire coil temperature protection device further comprises a triode Q402 and a comparator IC4B, wherein an emitter of the triode Q402 is connected with the power supply, a collector of the triode Q402 is connected with a partial pressure branch circuit which is formed by a resistance R415 and a resistance R416, the partial pressure branch circuit which is formed by the resistance R415 and the resistance R416 is connected with the ground, a base electrode of the triode Q402 is connected with the thermistor, after being connected with a resistance R417 in series, the thermistor is connected with the ground. A node between the node between the resistance R415 and the resistance R416 is connected with an input positive end of the comparator IC4B, the node between the thermistor RT and the resistance R417 is connected with an input negative end of the comparator IC4B, and an output end of the comparator is connected with the heating control circuit. The induction cooker wire coil temperature protection device has strong anti-jamming performance and rapid protection speed.
Description
Technical field
The utility model belongs to the electromagnetic oven field, relates in particular to a kind of drum protective device of electromagnetic oven.
Background technology
Electromagnetic oven is as a kind of emerging kitchen small household appliances, and with its flames of anger, heat efficiency advantages of higher is popularized very soon.In electromagnetic oven, drum is to be formed by multiply enamel covered wire (enamel insulated aluminium wire) coiling, is to produce resonance the critical elements of power output.Again because of the position of drum just under magnetic sheet, in heating process, drum can be subjected to the radiation of pan bottom heat.Boilers from drying burning or pan material not to the time, drum self temperature can raise.When temperature surpasses the maximum temperature that enamel covered wire (enamel insulated aluminium wire) born, the strand insulation variation of enamelled wire, short circuit between strand is made whole electromagnetic oven and is damaged, and short circuit also is easy to cause naked light.Bring potential safety hazard to product user.
Also useful microprocessor MCU and thermistor survey line dish temperature in the prior art, but the method exists and takies microprocessor MCU resource, interference free performance is poor, and protection speed waits shortcoming slowly.
Summary of the invention
Poor for the interference free performance of the temperature protection circuit that overcomes existing electromagnetic oven wire coil, protect slow-footed deficiency, the utility model provides a kind of strong anti-interference performance, and protection speed is the electromagnetic oven wire coil temperature protective device rapidly.
The technical scheme that its technical problem that solves the utility model adopts is:
A kind of electromagnetic oven wire coil temperature protective device, comprise the heating control circuit that is used for being switched on or switched off the drum power supply according to control signal, and the thermistor RT that is used to detect the drum temperature, described electromagnetic oven wire coil temperature protective device also comprises triode Q402 and comparator IC4B, the emitter of described triode Q402 connects power supply, the collector electrode of described triode Q402 connects the dividing potential drop branch road of resistance R 415 and resistance R 416 formation, the dividing potential drop branch road ground connection that described resistance R 415 and resistance R 416 form, the base stage of described triode Q402 connects described thermistor, ground connection after described thermistor is connected with resistance R 417; Node between described resistance R 415 and the resistance R 416 connects the input anode of comparator IC4B, and described thermistor RT is connected the input negative terminal of comparator IC4B with the node between the resistance R 417, and the output of described comparator connects described heating control circuit.
Further, described power supply is by the node between resistance R 403 connection thermistor RT and the resistance R 417.
Further again, the input anode of described comparator IC4B is connected the output of comparator IC4B with diode D406 by resistance R 408.
Further, the output of described IC4B connects described heating control circuit by backward diode D403.
Technical conceive of the present utility model is: utilize thermistor change in resistance characteristics when variations in temperature, thermistor with its minute piezoelectricity form the bleeder circuit of connecting, dividing point connects with the comparator input pin.When temperature was low, thermistor was big, and the voltage of dividing point is lower than the reference voltage with comparator, comparator output Gao Ping; When temperature reaches the protection point; the voltage of dividing point is higher than the reference voltage with comparator, and comparator output protection level (low level) makes electromagnetic oven fall power or closes heating; guaranteed that effectively electromagnetic oven wire coil self temperature is no more than standard value, prolonged the useful life of electromagnetic oven.This circuit also has thermistor error protection characteristic, when thermistor open circuit or in short-term, circuit is in protection level output state always.
The beneficial effects of the utility model mainly show: 1, strong anti-interference performance, and protection speed is rapid; 2, prolong the useful life of electromagnetic oven; 3, has thermistor error protection characteristic.
Description of drawings
Fig. 1 is the circuit diagram of electromagnetic oven wire coil temperature protective device.
Embodiment
Below in conjunction with accompanying drawing the utility model is further described.
With reference to Fig. 1, a kind of electromagnetic oven wire coil temperature protective device, comprise the heating control circuit that is used for being switched on or switched off the drum power supply according to control signal, and the thermistor RT that is used to detect the drum temperature, described electromagnetic oven wire coil temperature protective device also comprises triode Q402 and comparator IC4B, the emitter of described triode Q402 connects power supply, the collector electrode of described triode Q402 connects the dividing potential drop branch road of resistance R 415 and resistance R 416 formation, the dividing potential drop branch road ground connection that described resistance R 415 and resistance R 416 form, the base stage of described triode Q402 connects described thermistor, ground connection after described thermistor is connected with resistance R 417; Node between described resistance R 415 and the resistance R 416 connects the input anode of comparator IC4B, and described thermistor RT is connected the input negative terminal of comparator IC4B with the node between the resistance R 417, and the output of described comparator connects described heating control circuit B.
The node that described power supply connects between thermistor RT and the resistance R 417 by resistance R 403, described power supply connect the base stage of triode Q402 by resistance R 404.
The input anode of described comparator IC4B is connected the output of comparator IC4B with diode D406 by resistance R 408.
The output of described IC4B connects described heating control circuit by backward diode D403.
In the present embodiment, the circuit that triode Q402 and thermistor RT form.The Q402 base current is through thermistor RT, and R417 arrives ground, the Q402 conducting, and voltage adds to the R415 upper end, and R415 and R416 dividing potential drop obtain the reference voltage of IC4B comparator anode; Thermistor RT (is example with the negative tempperature coefficient thermistor) resistance diminished when the drum temperature raise, and RT and R417 dividing point (linking with IC4B comparator negative terminal) raise.When temperature reached the protection point, the voltage of dividing point was higher than the reference voltage with comparator, comparator output protection level (low level).Make electromagnetic oven fall power or close heating, guaranteed that effectively electromagnetic oven wire coil self temperature is no more than standard value, prolong the useful life of electromagnetic oven.D403 is an isolating diode, and effect is in temperature just often, makes temperature protection circuit not influence front stage circuits.
The open circuit short-circuit detecting of thermistor, when thermistor RT opened a way, the Q402 base stage is no current over the ground, and Q402 ends, and the IC4B anode is a zero potential, and negative terminal provides voltage by R403, and negative terminal voltage is higher than anode, comparator output protection signal.During the thermistor short circuit, when raise surpassing reference voltage with the drum temperature in like manner.
The protection delay circuit, when IC4B comparator output LOW voltage, diode D406, resistance R 408 feeds back to the comparator anode with this low-voltage.To prolong guard time.
Claims (5)
1, a kind of electromagnetic oven wire coil temperature protective device, comprise the heating control circuit that is used for being switched on or switched off the drum power supply according to control signal, and the thermistor RT that is used to detect the drum temperature, it is characterized in that: described electromagnetic oven wire coil temperature protective device also comprises triode Q402 and comparator IC4B, the emitter of described triode Q402 connects power supply, the collector electrode of described triode Q402 connects the dividing potential drop branch road of resistance R 415 and resistance R 416 formation, the dividing potential drop branch road ground connection that described resistance R 415 and resistance R 416 form, the base stage of described triode Q402 connects described thermistor, ground connection after described thermistor is connected with resistance R 417;
Node between described resistance R 415 and the resistance R 416 connects the input anode of comparator IC4B, and described thermistor RT is connected the input negative terminal of comparator IC4B with the node between the resistance R 417, and the output of described comparator connects described heating control circuit.
2, electromagnetic oven wire coil temperature protective device as claimed in claim 1 is characterized in that: the node that described power supply connects between thermistor RT and the resistance R 417 by resistance R 403.
3, electromagnetic oven wire coil temperature protective device as claimed in claim 1 or 2 is characterized in that: the input anode of described comparator IC4B is connected the output of comparator IC4B with diode D406 by resistance R 408.
4, electromagnetic oven wire coil temperature protective device as claimed in claim 3, it is characterized in that: the output of described IC4B connects described heating control circuit by backward diode D403.
5, electromagnetic oven wire coil temperature protective device as claimed in claim 1 or 2, it is characterized in that: the output of described IC4B connects described heating control circuit by backward diode D403.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008200838305U CN201191928Y (en) | 2008-02-28 | 2008-02-28 | Temperature protection equipment for wire disc of electromagnetic furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008200838305U CN201191928Y (en) | 2008-02-28 | 2008-02-28 | Temperature protection equipment for wire disc of electromagnetic furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201191928Y true CN201191928Y (en) | 2009-02-04 |
Family
ID=40336087
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2008200838305U Expired - Lifetime CN201191928Y (en) | 2008-02-28 | 2008-02-28 | Temperature protection equipment for wire disc of electromagnetic furnace |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201191928Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102226539A (en) * | 2011-04-21 | 2011-10-26 | 浙江苏泊尔家电制造有限公司 | Induction cooker and temperature measurement method thereof |
-
2008
- 2008-02-28 CN CNU2008200838305U patent/CN201191928Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102226539A (en) * | 2011-04-21 | 2011-10-26 | 浙江苏泊尔家电制造有限公司 | Induction cooker and temperature measurement method thereof |
| CN102226539B (en) * | 2011-04-21 | 2015-07-15 | 浙江苏泊尔家电制造有限公司 | Induction cooker and temperature measurement method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203466131U (en) | Relay point starting control circuit | |
| CN102781130B (en) | Large-power electromagnetic cooker circuit based on power electronic technology | |
| CN201191928Y (en) | Temperature protection equipment for wire disc of electromagnetic furnace | |
| CN204241991U (en) | The temperature detection heat abstractor of transformer | |
| CN201674074U (en) | Smart socket | |
| CN201299427Y (en) | Rice cooker control circuit | |
| CN114640111A (en) | Load identification control system of power supply system | |
| CN203015157U (en) | High-power induction cooker circuit based on power electronics | |
| CN203263009U (en) | Electric heating cooking utensil | |
| CN208890347U (en) | A kind of temperature protection circuit for socket | |
| CN203104810U (en) | Heating device for preventing dry heating | |
| CN101728816A (en) | Motor overheat protector | |
| CN201233039Y (en) | Electromagnetic oven with wire coil temperature protection arrangement | |
| CN204520306U (en) | Water level detector and use the insulating pot of this water level detector | |
| CN204192349U (en) | A kind of electronic temperature-sensing type energy-saving prevention excessive pressure electric cooker | |
| CN210222578U (en) | Control circuit of mute heat preservation kettle | |
| CN201182522Y (en) | Safe type electrothermic smoldering stove | |
| CN104166415A (en) | Electric heating kettle controller capable of expelling toxin within three minutes | |
| CN203950223U (en) | A kind of tinware ware temperature control circuit that melts | |
| CN104728873B (en) | A kind of flame-out control method of kitchen range | |
| CN105662122A (en) | Alternating current-direct current dual-purpose temperature-control multipurpose electric pan | |
| CN202843362U (en) | Electronic timer for electric cooker | |
| CN201541357U (en) | APO (automatic power off) electrothermal tube with controllable silicon water level control | |
| CN201683689U (en) | Heat-preservation electric food warmer | |
| CN202613528U (en) | Wireless temperature measuring device for induction cooker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20090204 |