KR20020045913A - Locking detecting circuit in induction heating cooker - Google Patents

Abstract

PURPOSE: A circuit for sensing pressure fastening of induction heating cooker is provided to perform a double safety circuit simply according to a cover fastening by using a hall IC(integrated circuit). CONSTITUTION: A hall IC senses a fastening operation of a cover pressure of a cooker. A hall IC input power control unit(100) switches a supply power of the hall IC. A pressure fastening sensing unit(300) modifies an output voltage according to the sensing operation of the hall IC. A microcomputer controls the hall IC input power control unit(100), judges if the hall IC operates normally, and judges if the pressure fastening of the cover is performed according to the output voltage of the pressure fastening sensing unit(300).

Description

Locking detecting circuit in induction heating cooker

The present invention relates to a pressure tightening detection circuit of an induction heating cooker, and more particularly, to a pressure tightening detecting circuit of an induction heating cooker which implements a double safety against pressure tightening using a hole integrated circuit.

Induction heating cooker performs the cooking function by the way in which the eddy current flows when the magnetic wire generated from the working coil passes through the pot. Looking at the basic heating principle of the induction heating cooker, when a current is applied to the working coil, the oven is a magnetic material is heated by induction heating (heating), cooking in the oven is made.

Accordingly, in the case of the induction heating cooker, a high frequency voltage having a predetermined size must be applied to the working coil in order to generate magnetic lines, and the working coil has a strong thermal power of about 1300 W by the applied high frequency voltage.

The induction heating cooker which performs cooking operation with such a strong fire power also uses the principle of a pressure cooker. That is, the air generated during heating does not flow out, and the cooking operation is performed while maintaining a high pressure in the pot. Therefore, since the induction heating cooker performs cooking operation at very high pressure and high heating power, it may cause a safety risk of the consumer by a malfunction of the user or a malfunction of the cooker itself.

Therefore, the conventional induction heating cooker is to add a safety device to the lid opening and closing handle, to prevent the safety risks of consumers in advance.

1 is a block diagram for detecting the locked state and the open state of the lid opening and closing handle of the conventional induction heating cooker.

The lid pressure fastening of the conventional induction cooker is detected by the reed switch (SW1) and the magnet (MGT). The magnet (MGT) is installed on one side of the handle to rotate for fastening the lid, by detecting the magnetic field generated by the magnet (MGT), the reed switch (SW) for detecting the position of the magnet (MGT) is installed do. The installation position of the reed switch is where the magnet and the reed switch come closest to each other when the handle is rotated to engage the locking ring and the oven.

Therefore, as shown in FIG. 1, when the magnet MTG and the reed switch SW maintain a horizontal distance horizontally, and the magnet MGT approaches the reed switch SW, the magnet As the field becomes stronger, the reed switch SW is turned on.

In order to sense the operation state of the reed switch SW, the circuit shown in FIG.

The microcomputer 10 determines the open state and the locked state of the lid open / close handle by a signal input to the input terminal.

A +5 volt Vcc power is supplied to the input terminal of the microcomputer 10 through a resistor R1. In addition, another resistor R2 is connected in series with the resistor R1 between the Vcc power supply and the ground. Another resistor R3 is connected to the connection point a between the two resistors R1 and R2 connected in series, and two reed switches SW1 and SW2 are connected between the resistor R2 and the resistor R3. Are connected in series. The lid switches SW1 and SW2 are turned on when the lid opening / closing handle is in the locked state according to the operation of the lid opening / closing handle (not shown), and when the lid opening / closing handle is in the open state. Operates in the off state.

Next will be described the operation detection process of the lid opening and closing handle of the conventional induction heating cooker made of the above configuration.

If the high pressure is maintained in the oven, the lid opening and closing handle (not shown) should have a locked state, and in conjunction with this, the reed switches SW1 and SW2 will be in an on state.

At this time, a voltage of about 0.7 volt is applied to the connection point a through the reed switches SW1 and SW2 to the divided voltage of the resistor R1 and the parallel resistors R2 and R3. Therefore, when the reed switches SW1 and SW2 are in the on state, the input terminal of the microcomputer 10 senses a voltage of about 0.7 volts, and the lid opening / closing knob (not shown) is locked as the sensing voltage. I judge it.

Next, when the lid opening / closing handle (not shown) is in the open state, in conjunction with this, the reed switches SW1 and SW2 are turned off. Due to the OFF operation of the reed switch, a voltage of 4.3 volts divided by the resistors R1 and R2 is applied to the connection point a. Therefore, the divided voltage is input to the input terminal of the microcomputer 10.

Accordingly, when the reed switches SW1 and SW2 are in the off state, the microcomputer 10 senses a voltage of about 4.3 volts, and determines that the lid opening / closing handle is open as the sensing voltage at this time.

That is, in the conventional lid opening and closing handle motion detection device, when the magnet (MGT) maintains a constant distance horizontally with the reed switch (SW), when the magnet (MGT) approaches the reed switch (SW) direction, the reed switch (SW) ) Is activated to sense the pressure tightening of the lid.

However, in this configuration, the distance A varies depending on the strength of the magnet field of the magnet MTG. That is, when the strength of the magnet is high, the reed switch operates at a long distance, and when the strength is low, the reed switch operates only by reaching a close distance. That is, the conventional lid fastening detection device has a problem that a deviation occurs at the time of operation of the reed switch according to the field strength of the magnet.

In addition, the same phenomenon as that of the strength of the magnet field occurs due to the variation in the operating sensitivity of the reed switch. That is, in the conventional lid fastening detection device, the deviation occurred at the time of operation also by the deviation of the operation sensitivity of a reed switch.

In addition, the conventional lid fastening detecting device has no method that the microcomputer 10 can detect the defective part of the reed switch itself. Therefore, since there is no countermeasure against short-circuit of a single product, there is a problem of raising the manufacturing cost by applying a method of connecting two reed switches in series to configure a double safety mode.

Accordingly, an object of the present invention is to provide a pressure tightening detecting device for an induction heating cooker which can easily implement a double safety circuit according to a cap fastening using a hole integrated circuit.

1 is a structural diagram illustrating a pressure coupling of a conventional induction heating cooker,

2 is a pressure coupling detection circuit diagram of a conventional induction heating cooker,

3 is a pressure fastening detection structure diagram of the induction heating cooker according to the present invention,

4 is a block diagram illustrating the pressure fastening of the induction heating cooker according to the present invention;

5 is a pressure coupling detection circuit diagram of the induction heating cooker according to the present invention.

Explanation of symbols on the main parts of the drawings

100: hall integrated circuit input power control unit 200: pressure tightening detection structure

300: pressure fastening detection unit 400: hole integrated circuit output unit

500: microcomputer

The pressure fastening detecting device of the induction heating cooker according to the present invention for achieving the above object has an operating characteristic when the power is applied, and a hole integrated circuit for detecting the fastening operation of the cooker lid pressure; A hall integrated circuit input power controller configured to open and close a supply power of the hall integrated circuit; A pressure fastening detecting unit for changing an output voltage according to a sensing operation of the hole integrated circuit; The microcomputer is configured to control the hall integrated circuit input power control unit to determine whether the hall integrated circuit is normally operated and to determine whether the cap is fastened according to the output voltage of the pressure fastening detecting unit.

The hole integrated circuit may detect the fastening of the lid pressure in a state in which the magnet installed in the lid is moved horizontally by a predetermined distance and then moved vertically by a predetermined distance.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the pressure tightening detection device of the induction heating cooker according to the invention.

3 is a structural diagram for detecting the pressure fastening of the induction heating cooker according to the present invention.

Induction heating cooker of the present invention, it characterized in that to use the hole integrated circuit (H) to detect whether the pressure of the cap. The hole integrated circuit H is configured to have a horizontal distance A and a vertical distance Gap between the magnets MTG.

That is, the strength of the magnet field of the magnet MTG is operated at a vertical distance Gap. When the magnet MGT approaches the lower end of the hole integrated circuit H, the hole integrated circuit H is turned on. The deviation of the magnet MGT and the operation deviation due to the characteristics of the hole integrated circuit H are affected only by the vertical distance Gap and the horizontal size of the magnet. Therefore, the deviation of the operating point between products can be minimized because the deviation in the horizontal direction is eliminated as in the prior art.

Next, Figure 4 is a block diagram of the pressure tightening detection device of the induction heating cooker according to the present invention.

As shown in FIG. 3, the pressure fastening detecting device of the induction heating cooker according to the present invention uses a pressure fastening detecting part composed of the hole integrated circuit (H). The pressure fastening sensing structure 200 according to the operation of the hole integrated circuit H and the magnet MTG is formed by horizontal and vertical structures of the magnet and the hole integrated circuit. That is, the sensing structure between the magnet MTG and the hole integrated circuit H is set to a vertical gap Gap together with the horizontal structure of the conventional reed switch. In this case, the horizontal structure is set in the direction of pressure tightening, and the sensing region is set to the vertical gap (Gap) to reduce the deviation of the existing sensing region considerably.

It includes a pressure fastening detecting unit 300 for detecting whether the pressure of the lid according to the moving state of the pressure fastening detecting structure 200. The output of the pressure fastening detecting unit 300 is input to the microcomputer 400 through the hole integrated circuit output terminal 400. Therefore, the microcomputer 400 determines whether the cap is fastened by the signal.

In addition, the pressure fastening detection device of the induction heating cooker of the present invention comprises a hall integrated circuit input power control unit 100 for controlling the power of the hall integrated circuit (H). The operation of the hall integrated circuit input power controller 100 is controlled by the microcomputer 500. In addition, the microcomputer 500 detects whether the hole integrated circuit H, which is the pressure fastening detection component, is normally operated through the hole integrated circuit output terminal 400.

That is, the microcomputer 500 controls the operation of the hole integrated circuit input power controller 100 to detect a failure of the hole integrated circuit itself, which is a pressure fastening sensing component. Then, it is determined whether the cap is fastened by the signal detected when the power is applied.

Next, the present invention will be described in more detail with reference to a detailed circuit diagram of a pressure tightening detecting apparatus for an induction heating cooker according to the present invention shown in FIG.

The pressure fastening detection device of the induction heating cooker according to the present invention, as shown, includes a hole integrated circuit (H). The power supply of the hole integrated circuit (H) is controlled by the hole integrated circuit input power control unit 100, the output of the hole integrated circuit (H) to the pressure tightening detection unit 300 for detecting whether the pressure of the lid is fastened. Is approved. Although not shown in FIG. 5, the control of the hall integrated circuit input power control unit 100 is controlled by a microcomputer, and likewise, the output of the pressure fastening detecting unit 300 is also input to the microcomputer.

The hall integrated circuit input power control unit 100 includes a switching element Q1 operated under the control of the microcomputer. When the signal is applied from the microcomputer, the switching element Q1 is configured to apply 5 volts of supply power to the hole integrated circuit H.

The pressure fastening detecting unit 300 is configured to apply the output of the Hall integrated circuit H to a microcomputer. In other words, two resistors R11 and R12 are connected in series between the 5V supply and the ground. A resistor R13 is connected to the connection point a 'between the two resistors, and a signal is transmitted to the microcomputer through the resistor R13. The output terminal of the hole integrated circuit H is connected through another resistor R14 connected between the connection point a 'and the resistor R13.

The following describes the pressure fastening detection operation of the induction heating cooker according to the present invention having the above configuration.

In order to detect whether the lid is fastened by the microcomputer, when a low signal is applied to the switching element Q1 of the hall integrated circuit input power control unit 100, the switching element Q1 is turned on and is 5 volts. The supply power is supplied to the hall integrated circuit H.

At this time, while the power is supplied to the hole integrated circuit H, the hole integrated circuit H has operating characteristics according to the position of the magnet.

That is, when the magnet approaches the lower end where the hole integrated circuit H is located as shown in Fig. 3, the hole integrated circuit H is shorted. In this operation, the voltage divided by the three resistors R11, R12, and R14 (approximately 0.7 volts) is applied to the connection point a '. The voltage is applied to the microcomputer, sensing the lid pressure tightening.

When the magnet is positioned away from the hole integrated circuit H, the hole integrated circuit H is opened, and a voltage divided by two resistors R11 and R12 at a connection point a '(about 4.3 volts) is obtained. ) Is applied. This voltage is applied to the microcomputer, which senses the pressure release of the lid.

Meanwhile, the microcomputer receives 0.7 volts from the pressure fastening detecting unit 300 and senses that the pressure of the lid is fastened. The high signal is applied to the switching element Q1 of the Hall integrated circuit input power controller 100. To switch off.

At this time, since the power applied to the hole integrated circuit is cut off, the operating characteristic of the hole integrated circuit should be eliminated in the normal operation state of the hole integrated circuit. Therefore, even if the magnet is located at the lower end of the hole integrated circuit H, which is a fastening position, the hole integrated circuit H has an open state. In this case, therefore, the voltage divided by the two resistors R11 and R12 must be applied to the connection point a '. However, when the hole integrated circuit H is in a bad state, the short state can be maintained continuously. In this state, a voltage of 0.7 volt is applied to the connection point a '.

Therefore, the microcomputer first supplies power to the hole integrated circuit (H), detects a pressure-tightening state of the lid, and then cuts off power applied to the hole integrated circuit (H) at the same position of the magnet and the hole integrated circuit. In this way, it is determined whether the hall integrated circuit H is operating normally. According to this determination operation, the microcomputer performs control to turn off the output for heating the cooker when the hall integrated circuit is defective.

In addition, the microcomputer generates a problem on the control board PCB when the abnormal voltage is continuously input through the pressure fastening detecting unit 300 even after determining whether the hall integrated circuit is operating normally. The controller determines to take the action accordingly. That is, in this way, when a problem occurs on the hall integrated circuit or the control board, damage to the product, and in order to prevent the occurrence of a fire, the output for heating the cooker is controlled to the off state.

That is, the present invention uses a hole integrated circuit, which is a semiconductor device that operates when 5 volts of power is applied, to detect whether the lid pressure is fastened and to determine whether the hole integrated circuit itself is broken. It is a basic technical idea to adopt.

And within the scope of the technical idea of the present invention, of course, various modifications are possible to those skilled in the art.

The present invention described above has the following effects.

First, the Hall integrated circuit is applied to the pressure tightening detection device of the induction heating cooker, the reliability of the single product is significantly higher than the conventional.

Second, the sensing structure of the Hall integrated circuit, in addition to the horizontal structure of the conventional reed switch to sense in the area of the vertical gap, the horizontal structure is set in the direction of the locking device to significantly reduce the deviation of the existing detection area by significantly reducing the deviation of the product Has the advantage of decreasing.

Third, it is possible to determine whether the defect of the unit by turning on / off the input power of the Hall integrated circuit by taking advantage of the characteristic of operating at the time of power input of the Hall integrated circuit, thereby reducing the reliability and cost as well as the double safety structure. You get

Claims (2)

A hall integrated circuit having an operating characteristic when the power is applied and detecting a fastening action of the cooker lid pressure; A hall integrated circuit input power controller configured to open and close a supply power of the hall integrated circuit; A pressure fastening detecting unit for changing an output voltage according to a sensing operation of the hole integrated circuit; An induction heating cooker comprising a microcomputer controlling the hall integrated circuit input power control unit to determine whether the hall integrated circuit is normally operated and determining whether the lid is fastened according to the output voltage of the pressure fastening detecting unit. Pressure tightening detection device. The method of claim 1 wherein: The hole integrated circuit, the pressure fastening detection device of the induction heating cooker, characterized in that the magnet installed in the lid is moved horizontally by a predetermined distance, and then the tightening of the lid pressure in a state moved vertically by a predetermined distance.