CN201680452U

CN201680452U - Electromagnetic oven with function of automatic power off

Info

Publication number: CN201680452U
Application number: CN2009202057259U
Authority: CN
Inventors: 徐守则
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-10-10
Filing date: 2009-10-10
Publication date: 2010-12-22
Anticipated expiration: 2019-10-10

Abstract

An electromagnetic oven with the function of automatic power off after water boiling adopts the scheme that a coil panel, a circuit board and a force transducer are arranged in a housing; three support legs are provided, wherein two support legs are fixed on the housing, and the other support leg is connected with the housing after passing through the force transducer; a resistance strain gage is arranged on the force transducer, a switching signal is output to a single-chip microcomputer through amplification, differentiation, amplification and integration of a signal induced by the resistance strain gage, and the single-chip microcomputer controls the power on and off of the electromagnetic oven. The electromagnetic oven adopts the working principle that water is turned into water vapor and drifts away after boiling, the force transducer induces a weightless signal which is processed through the circuit, and the automatic power-off of the electromagnetic oven can be controlled.

Description

The electromagnetic oven of automatic outage

Affiliated technical field

The utility model relates to a kind of electromagnetic oven, especially the electromagnetic oven that can cut off the power supply automatically behind the Shi Shuikai that heats up water.

Background technology

At present, electromagnetic oven does not have water to open the back function of outage automatically when heating up water, and gives and brings danger when using.

What can cut off the power supply automatically behind the Shi Shuikai that heats up water at present, is a kind of insulating pot.It mainly is made up of kettle body, electrothermal wire heating's dish, bimetal leaf steam switch, lever, electric contact.After electrothermal wire heating dish was boiled with the water in the kettle body, the steam of generation waftd around bimetal leaf, the bimetal leaf upset of being heated, and the drive lever motion, the motion of lever separates electric contact, thereby reaches the purpose of automatic outage.The shortcoming that this kind technology exists is: bimetal leaf steam switch and electric contact are in the hot and humid environment, and reliability is reduced, and bimetal leaf steam switch is corroded easily, and electric contact is struck sparks easily.The electrothermal wire heating is coiled extreme temperatures, has serious expanding with heat and contract with cold, and easily makes the kettle body deformability, produces many problems.Therefore, the kettle body needs high-intensity design, causes cost height, heaviness.Kettle body interior shape complexity, not easy to clean.

Summary of the invention

Can not cut off the power supply automatically behind the Shi Shuikai that heats up water in order to overcome existing electromagnetic oven, the deficiency that the insulating pot reliability is not high, use is inconvenient, the utility model provides a kind of electromagnetic oven of automatic outage, the electromagnetic oven of this automatic outage has kept that common electromagnetic oven is easy to use, reliability is high, the advantage of sanitation and hygiene, has increased the function that can cut off the power supply automatically behind the Shi Shuikai that heats up water simultaneously again.

The technical scheme that its technical problem that solves the utility model adopts is: existing electromagnetic oven is designed to three legs, and two legs are fixed on the shell, and another leg is connected with shell after through a force cell.Switching signal of output behind the output signal of telecommunication process amplification for the first time of force cell, differential, the amplification second time, the integration, this switching signal is transferred among the single-chip microcomputer of electromagnetic oven, and single-chip microcomputer sends the signal cut power supply.Its operation principle is: force cell perception part electromagnetic oven adds the gravity that pot body adds water, and exports an analog electrical signal, is input in the differential circuit after amplifying for the first time.When water also not when boiled, the gravity of force cell perception does not change, signal after the output signal of force cell is amplified for the first time with process does not change, differential circuit does not change yet, the input of differential circuit, output remain on the electrical voltage point of setting, amplifying circuit, integrating circuit do not change yet for the second time, and the switching signal of integrating circuit output is not overturn, and electromagnetic oven continues heating.And because the different initial gravity that what, the variation of placement location of difference, the water of pot cause is converted into dc signal via force cell, when inputing to differential circuit after amplifying for the first time, isolated out by differential circuit.When water when boiled, water becomes steam and flies away, force cell perception electromagnetic oven adds the gravity continuous decrease that pot body adds water, corresponding output signal continues to change, through amplifying back input differential circuit for the first time.Differential circuit is transferred to amplifying circuit for the second time with the changing unit of the signal of telecommunication, and amplifying circuit is transferred to integrating circuit after signal is amplified for the second time, and the signal that integrating circuit is exported after with signal integration overturns as switch.Adjust the reference voltage of one of them input of integrating circuit, can obtain the integration direction of needs, and can filter out the interfering signal that causes owing to vibration, air-flow etc., output signal behind all right suitable time-delay, make the many boilings of water for a moment, get rid of the pernicious gas in the water.The output signal of integrating circuit is transferred to the single-chip microcomputer of electromagnetic oven, and single-chip microcomputer sends a signal of cutting off the electricity supply after receiving signal, and electromagnetic oven outage automatically stops heating.

The beneficial effects of the utility model are: easy to use, safe when heating up water with the electromagnetic oven of this automatic outage, health, dependable performance, simple in structure, only need on common electromagnetic oven, increase simple force cell and circuit, and can cook with pressure cooker, reach one-object-many-purposes.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further specified.

Fig. 1 is a force cell installation diagram of the present utility model.

Fig. 2 is the upward view of Fig. 1.

Fig. 3 is circuit theory diagrams of the present utility model.

Among the figure: 1. circuit board, 2. resistance strain gage, 3. force cell, 4. first leg, 5. second leg, 6. screw, 7. shell, 8. coil panel, 9. the 3rd leg.

The specific embodiment

In Fig. 1: coil panel (8) and circuit board (1) are arranged among shell (7), force cell (3) is a cantilevered elastomer, be fixed on the shell (7) by screw (6), has a slice resistance strain gage (2) on the force cell (3) at least as inverting element, the other end of force cell (3) is connecting first leg (4), first leg (4) with contact, the signal of resistance strain gage (2) output is through amplifying the first time of circuit board (1), differential, amplify for the second time, be input to single-chip microcomputer behind the integration, single-chip microcomputer decision coil panel (8) is that energising heating or outage stop to heat.

In Fig. 2: second leg (5) is fixed on the shell (7) with the 3rd leg (9), with the gravity of first leg (4) together support electromagnetic oven, pot body, water, and approximate evenly distribution.

In Fig. 3: R1, R2, R3, R4 form bridge circuit, and wherein R1 is the resistance of resistance strain gage (2), when water when boiled, it is big that the resistance of R1 becomes, the in-phase input end voltage of operational amplifier A 1 reduces.Be input to capacitor C 1 through operational amplifier A 1, feedback resistance R5 after amplifying.Then through being input to resistance R 10 behind C1, R6, R7, the A2 differential.Be input to resistance R 12 through R10, R11, A3 after amplifying again.Wherein R8, R9 are used to set the operating point of operational amplifier A 2, A3.R12, R13, C2, A4 form integrating circuit, R13 is an adjustable resistance, be used to adjust the homophase input voltage of operational amplifier, the careful R13 that adjusts, make it when water not when boiled, operational amplifier A 4 is output LOW voltage just, when water when boiled, operational amplifier begins integration and boosts, last output HIGH voltage.

Claims

1. the automatic electromagnetic oven of outage has coil panel and circuit board among shell, it is characterized in that have three legs, two legs are fixed on the shell, and another leg is connected with shell after through a force cell.

2. the electromagnetic oven of automatic outage according to claim 1 is characterized in that, force cell is a cantilevered elastomer, has a slice resistance strain gage on it at least.

3. the electromagnetic oven of automatic outage according to claim 2 is characterized in that, to the signal processing mode of resistance strain gage be amplification for the first time, differential, amplify for the second time, integration, export a switching signal at last.