KR0176776B1 - Controller for induction heater - Google Patents

Abstract

The present invention relates to a reservation cooking control method of the electromagnetic induction heating rice cooker, which gives a heat evenly to the rice by varying the duty according to the appropriate soak setting time and its soaking time in the soaking process at the time of the reservation cooking. The moisture content is evened out to achieve the best cooking.

Counting the reservation time in the reservation cooking mode according to the present invention and comparing the first and second reservation setting times with each other; Performing a soaking process by varying the soak setting time according to a comparison result between the reservation time and the first and second reservation setting times; Performing a cooking process by setting a duty ratio proportionally according to the set soak setting time; Achieved by

Description

Pre-cooking control method of electromagnetic induction heating rice cooker

1 is a flow chart of reserved cooking control signal in a conventional electromagnetic induction heating rice cooker.

2 is a cross-sectional view of the electromagnetic induction heating rice cooker for realizing the reservation cooking control process of the present invention.

3 is a block diagram of a cooking control device of the present invention induction heating rice cooker.

Figure 4 is a graph showing the heating temperature during the soaking, cooking, moxibustion process according to FIG.

FIG. 5 is a signal flow diagram of reservation reservation control process using FIG.

* Explanation of symbols for main parts of the drawings

100: first rectifying means 101: smoothing means

102: inverter means 103: inverter control means

104: switching drive means 105: current detection means

106: negative feedback amplification means 107: integral means

111: key operation means 112: system control means

The present invention relates to the reservation cooking control of the electromagnetic induction heating rice cooker, and more specifically, to have the heat distribution and the water content of the rice by the appropriate time and output (Duty) control according to the reservation time during the soaking process The present invention relates to a method of controlling cooking reservation of an electromagnetic induction heating rice cooker to prevent the occurrence of unripe ice and to make an optimum cooking.

In general, in order to perform the cooking process with an electric rice cooker, put the rice soaked in water in the container of the rice cooker and press the cooked water after supplying the appropriate amount of water according to the number of servings, the initial absorption of rice water For this purpose, the heater heater and the side heater are heated to 120 ° C. and 100 ° C., respectively, to perform the cooking process.

As such, when the cooking process is performed, the temperature sensing elements installed on the lower and side surfaces of the rice cooker sense the lower temperature and the side temperature in the vessel, and stop the cooking process when the temperature reaches the set temperature, and lower the heat generation amount of the lower heater and the side heater, so To be performed.

After the moxibustion process is completed, the upper heater is heated to about 70 ° C. according to the user's choice to perform the warming process.

In order to perform the cooking process with the electromagnetic induction heating rice cooker, the rice is put into a metal pan of the rice cooker, and after supplying water according to the appropriate amount of water, the cooker is pressed, and then the lower heater to perform the soaking process at the beginning. The working coil and the metal fan of the inverter means are heated to 58 ° C. required for the soaking process by the electromagnetic induction effect due to the magnetic field to perform the soaking process.

Thereafter, when the soaking process is completed, the cooking process, which is the next process, is performed to heat the metal pan to 120 ° C. required for the cooking process.

After the cooking process is completed, the cooking is completed by adjusting the temperature in the order of the moxibustion process, the warming process.

By the way, when the reservation is to be made in the electromagnetic induction heating rice cooker as described above is made through the signal flow as shown in FIG.

That is, when the user presses the reservation key through the key operation means to set the reservation (ST1) and sets the reservation time (ST2), the microprocessor (not shown in the drawing) is currently turned off from the reservation time setting state. The time of counting is started (ST3).

Thereafter, the microprocessor periodically searches whether the current time reaches the reservation time (ST4), and when the current time reaches the reservation time, the microprocessor induces power to the electromagnetic induction cooker to start cooking (ST5).

When the cooking is started, the microprocessor first operates an internal timer to perform the soaking process and heats the metal pan to a soaking temperature (58 ° C.) suitable for the soaking process for a set time (20 minutes) (ST6).

Then, if the internal temperature of the metal fan is searched through the lower temperature sensing element and the temperature does not reach the soak temperature (58 ° C), the duty ratio of the conduction and shutdown time of the switching element configured in the inverter means is set to With the power, the metal fan is heated through the working coil for the set time (20 minutes) (ST7).

When the set time (20 minutes) has elapsed, as described above, the temperature of the metal pan is heated to 110 ° C. to perform the cooking process (ST8), and when the cooking process is completed, the pause / moxa process is performed.

However, in such a general rice cooker, the electric rice cooker is cooked mainly in the cooking process, the moxibustion process and the warming process without a soaking process, so that the rice is uncooked on the bottom of the container depending on the amount of water supplied. There was this.

In addition, in the latter electromagnetic induction heating rice cooker, the rice in the metal pan is cooked evenly regardless of the upper and lower sides due to the electromagnetic induction effect caused by the magnetic field between the metal pan and the working coil. Although there is a difference in the rate of penetration of rice, the soaking time (20 minutes) is set equally regardless of the reservation time in the soaking process, so the rice is unripe due to lack of water in the upper part after cooking. This phenomenon caused many problems in terms of actual quality.

Accordingly, an object of the present invention is to give a heat evenly to the rice by varying the appropriate soak setting time and the duty according to the soak setting time in the soaking process at the time of reservation in consideration of the conventional problems as described above. The present invention provides a method of controlling cooking reservation of an electromagnetic induction heating rice cooker so as to optimally cook rice.

Still another object of the present invention is to maintain an equilibrium in the temperature rise of the upper temperature sensing member at the initial stage of the soaking process and to evenly improve the temperature of the load by making the load temperature even.

The reservation cooking control method of the electronic induction heating rice cooker according to the present invention for achieving the above object comprises the step of comparing the first and second reservation setting time by counting the reservation time in the reservation cooking mode; Performing a soaking process by varying the soak setting time according to a comparison result between the reservation time and the first and second reservation setting times; And performing a cooking process by proportionally setting the duty according to the set soak set time.

Hereinafter, described in detail with reference to the accompanying drawings of the present invention.

2 is a cross-sectional view of the electromagnetic induction heating cooker for realizing the reservation cooking process of the present invention, as shown in this, is installed in the upper portion of the electromagnetic induction heating rice cooker 126 is heated in the thermal insulation mode to maintain a constant temperature An upper heater 116 for holding; A side heater 118 installed circumferentially on the inner side of the cooker 126 to selectively heat with the upper heater 116 in a warming mode to maintain warmth at a predetermined temperature; A metal fan 110 seated between the side heaters 118; A working coil 102a which is installed in the lower portion of the rice cooker 126 in a circumferential manner and is a lower heater for heating the metal fan 110 by an electromagnetic induction effect; Located at the top and side of the cooker 126, the upper and side temperature sensing member 120, 122 for measuring the upper and side temperature inside the cooker; A lower temperature sensing member 123 positioned at a lower position of the cooker 126 to sense a lower temperature; Located in the lower position of the cooker 126 is configured as a cooling fan 114 for cooling the inside of the cooker.

3 is a system configuration diagram of the reservation cooking control device of the electromagnetic induction heating rice cooker of the present invention, as shown in the drawing, key operation means 111 for allocating a reservation function and a heat retention function by allocating a reservation key; First to third analog / digital converting means 119 and 121 for converting the temperature signal detected by the upper temperature sensing member 120, the side temperature sensing member 122, and the lower temperature sensing member 123 into digital signals. 123; When the current temperature change value converted by the first to third analog / digital conversion means 119 (121) 123 and the reservation cooking mode are selected from the key operation means 111 and the reservation time t1 is set, The reservation time t1 is counted and compared with the first and second reservation setting times t2 and t3. The comparison is made with the first and second soak set times t2 and t3 according to the comparison result. According to the comparison result, the first and second soak set time (t11) (t12) and the duty ratio to perform the soaking process, and after completion of the soaking process, the system for controlling the cooking process, rest / moxibustion process and the insulation process Control means 112; First rectifying means (100) for rectifying the input AC power source (AC) with a pulsating DC voltage; Smoothing means (101) for smoothing the pulsating DC voltage rectified by the first rectifying means (100) to the choke coil (L1) and the condenser (C1) constantly; Resonating the voltage output from the smoothing means 101 according to the pulse width modulation signal input from the outside and induces vortex in the metal fan 110 to be heated by the electromagnetic induction effect due to the magnetic field generated by the resonance voltage Working coil 102a for heating food in the metal pan 110 to a desired heating temperature, resonant capacitor C2, damping diode D1, and switching element TR1 constituting a series of resonant circuits with the working coil 102a. Inverter means 102 consisting of; Inverter control means (103) for generating a pulse width modulated signal according to the resonance voltage generated by said inverter means (102); Switching driving means (104) for controlling the switching element (TR1) of the inverter means (102) in accordance with the pulse width modulation signal generated by the inverter control means (103); Current detecting means (105) for detecting a current in the input AC power source (AC); Negative feedback amplifying means 106 for comparing the voltage level detected by the current detecting means 105 with a reference level value set and input for each function from the system control means 112 and outputting a comparison deviation value. and; Integrating the comparative deviation value of the negative feedback amplifying means 106 and controlling the output pulse width modulation signal of the inverter control means 103 according to the integral value to turn on the switching element TR1 through the switching driving means 104. Integrating means 107 for determining on / off time; A transformer 108 for stepping down the input AC power; Second rectifying means (109) for rectifying the voltage stepped down by the transformer (108) to apply the operating voltage of the system control means (112); An upper heater driving means 115 and a side heater driving means 117 for generating heat to the upper heater 116 and the side heater 118 by the control signal output from the system control means 112; Display means 125 for displaying the various functional phases of the electromagnetic induction heating rice cooker by the control signal of the system control means 112.

The inverter control means (103) comprises: voltage detecting means (103a) for detecting a resonance voltage generated by the inverter means (102) to determine a triangle wave generation time; The triangular wave generating means 103b1 generates a triangular wave by the voltage detected by the voltage detecting means 103a and compares the generated triangular wave with the voltage integrated in the integrating means 907 through the comparing means 103b2. The pulse width modulation signal generating means 103b for generating a pulse width modulation signal for determining the on / off time of the switching element TR1 of the inverter means 102 according to the result. Is the resistance.

FIG. 5 is a signal flow diagram of the reservation processing control process using FIG. 2, and as shown in FIG. 5, when the reservation key of the key operation means 111 is selected (ST100) and the reservation time t1 is set, the reservation time ( counting t2) (ST101); Comparing the counted reservation time t2 with the first reservation setting time t2 (ST102); As a result of the comparison in step ST102, when the reservation time t2 is less than or equal to the first reservation setting time t2, cooking is started (ST103) and the first soaking time t11 is set to 20 minutes to perform a soaking process. Step ST104; Setting a duty ratio to 16 levels after completion of the soaking process (ST105); Performing a cooking process by heating the metal fan 110 through the working coil 102a of the inverter means 102 with the set duty (ST112); Comparing the second reservation setting time t3 with the second reservation setting time t3 if the reservation time t1 is equal to or larger than the first reservation setting time t2 = 3 hours as a result of the search in step ST102; As a result of the search, if the reservation time t1 is between the first reservation setting time t2 and the second reservation setting time t3 = 6 hours, cooking is started (ST107), and the second call setting time t12 is 10; Setting to minutes to perform a soaking process during that time (ST108); Setting the duty to 14 levels after completion of the soaking process (ST109); Performing a cooking process by heating the metal fan 110 through the working coil 102a of the inverter means 102 with the set duty (ST113); Starting cooking when the reservation time t1 is equal to or greater than the second reservation setting time t3 (ST110) as a result of the search in step ST106 and setting the duty to 12 levels without the soaking setting time (ST111); In step ST114, the inverter means 102 heats the metal fan 110 through the working coil 102a to perform the cooking process.

Thus, when described in detail with reference to Figures 2 to 5 the effect of the present invention made as follows.

First, the input AC power source AC is rectified to the pulsating DC voltage through the first rectifying means 100, and then smoothed through the choke coil 101a of the smoothing means 101, and the AC power source AC is again The voltage drops through the transformer 108 and is converted into a DC voltage through the second rectifying means 109 and applied to the operating voltage of the system control means 112.

The pulsating DC voltage smoothed by the smoothing means 101 is input to the inverter means 102.

At this time, after the user supplies rice and the appropriate amount of water to the metal pan 110 in the rice cooker 126 to make a reservation, selects the reservation mode key through the key operating means 111 (ST100) and the reservation time (t2). When the control unit 112 is set, the system control unit 112 displays the cooking mode through the display unit 125, and also counts the reservation time t1 through the timer in the self.

Of course, the power is turned off until the current time reaches the reservation time (t1), only the timer in itself is operated to count the time.

After that, when the current time reaches the reservation time t1, the system control means 112 determines whether the reservation time t1 counted through the timer is equal to or less than the first reservation setting time t2: 3 hours. Is compared (ST102).

As a result of the comparison, if the reservation time t1 is less than or equal to the first reservation setting time t2, that is, if the reservation time is less than or equal to 3 hours, the system control means 112 uses the voltage input from the second rectifying means 109. By operating the cooling fan 114 located in the lower portion of the rice cooker 126 initially through the fan drive means 113 for a predetermined time to maintain the internal temperature of the rice cooker 126 in parallel with the external temperature and weft It is started (ST103).

Thereafter, when a predetermined time elapses, the internal timer is operated to set the first soak setting time (t11: 20 minutes) (ST104), and during the first soak setting time t11, as shown in FIG. The reference voltage level value of the appropriate temperature (58 ° C.) is input to the negative feedback amplifying means 106 and the soaking step is displayed on the display means 125.

On the other hand, the base current of the inverter means 102 to the switching element TR1 corresponds to the switching drive means 104 in response to the pulse width modulated signal derived from the pulse width modulated signal generating means 103b of the inverter control means 103. Since the driving coil 102a and the resonant capacitor C2 are driven by the pulsating DC voltage input from the smoothing means 101, the working coil 102a and the resonant capacitor C2 are continuously resonated.

Accordingly, a large resonance current flows through the working coil 102a.

As a result, eddy currents are induced in the metal fan 110 to be heated due to the electromagnetic induction effect caused by the magnet generated from the working coil 102a. As a result, the metal fan 110 is heated and the food in the metal fan 110 is heated. Heated to the desired heating temperature.

At this time, the resonant voltage generated by the working coil 102a and the resonant capacitor C2 of the inverter means 102 is detected by the voltage detecting means 103a of the inverter control means 103 and the pulse width modulated signal generating means 103b. By controlling the triangular wave generating means (103b1) of the) to determine the triangular wave generation time.

The triangular wave generating means 103b1 generates a triangular wave signal for determining conduction and breaking time of the switching element TR1 of the inverter means 102 according to the voltage detected by the voltage detecting means 103a. It is input to the inverting terminal (-).

On the other hand, when the current detecting means 105 detects the current from the input AC power source AC and inputs it to the inverting terminal of the negative feedback amplifying means 106, the negative feedback amplifying means 106 is detected by the current detecting means 105. The comparison deviation value is compared with the reference voltage level of the temperature (58 ° C.) corresponding to the soaking process of the system control means 112 driven by the voltage level and the driving voltage of the second rectifying means 109. It will be entered at 107.

The integrating means 107 integrates the input comparison deviation value to determine the conduction time of the switching element TR1 of the inverter means 102 via the diode D2, and the non-inverting terminal of the comparing means 103b2. Will be entered in (+).

Accordingly, the comparing means 103b2 compares the triangular pulse of the triangular wave generating means 103b1 with the integral value of the integrating means 107 to determine the conduction and breaking time of the switching element TR1 of the inverter means 102. By inputting and driving the width modulation signal to the switching driving means 104, the switching element TR1 of the inverter means 102 is turned on and off to effectively drive the working coil 102a to provide food in the metal pan 110. The soaking process is performed while heating.

As described above, the system control means 112 which performs the soaking process by heating the metal fan 110 by the working coil 102a of the inverter means 102 is provided with a lower temperature sensing member installed under the metal fan 110. 123 and the third analog / digital converting means 124 measure the current temperature of the metal fan 110 and compare it with the set soak temperature (58 ° C.).

At this time, if the lower temperature measured by the lower temperature sensing member 123 does not reach the soak temperature (58 ° C.) as shown in FIG. 4, the switching element TR1 configured in the inverter means 102 until the soak temperature is reached. ) Is maintained and maintained until the first set time t11 is reached.

After the soak temperature is reached and the first soak set time t11 elapses, it is determined that the soak process is completed and the duty ratio of the conduction / break time of the switching element TR1 configured in the inverter means 102 to perform the cooking process. Is input to the negative feedback amplifying means 106 as 15: 1, that is, 16 levels of full power (ST105).

Accordingly, the negative feedback amplifying means 106 compares the voltage level detected by the current detecting means 105 with the duty ratio value of the switching element TR1 input by the system control means 112 as described above. The comparison deviation value is input to the integrating means 107.

The integrating means 107 integrates the input comparison deviation value to determine the conduction time of the switching element TR1 of the inverter means 102 via the diode D2, and the non-inverting terminal of the comparing means 103b2. Will be entered in (+).

Accordingly, the comparing means 103b2 compares the triangular pulse of the triangular wave generating means 103b1 with the integral value of the integrating means 107 to determine the conduction and breaking time of the switching element TR1 of the inverter means 102. By inputting and driving the width modulation signal to the switching driving means 104, the switching element TR1 of the inverter means 102 is turned on for 15 seconds, cut off for 1 second, and then turned on again for 15 seconds. As the conduction and interruption during the first soak set time (t11 = 20 minutes) while the metal fan 110 is properly heated to the cooking temperature (110 ℃-120 ℃) through the working coil (102a) to perform the cooking process. (ST112).

In addition, when the lower temperature of the metal pan 110 reaches the cooking temperature, the cooking process is completed and the steaming process is performed.

If the reservation time t1 read through the timer as the result of the search in step ST102 is equal to or greater than the first reservation setting time t2: 3 hours, the reservation time t1 is the second reservation setting time t3 = 6 hours) or less or more (ST106).

As a result of the comparison in the step ST106, if the reservation time t1 exists between the first reservation setting time t2 and the second reservation setting time t3, that is, the reservation time exists between 3 to 6 hours. The system control means 112 sets the second soak setting time (t12: 10 minutes) by operating the internal timer while performing cooking in the same manner as described above (ST107) (ST108) and setting the second soaking. During the time t12, the lower temperature sensing member 123 heats the metal fan 110 through the working coil 102a of the inverter means 102 at a temperature (58 ° C) suitable for the soaking process, as shown in FIG. And the internal temperature of the metal fan 110 through the third analog / digital conversion means 124.

If the sensed internal temperature of the metal fan 110 does not reach the soak temperature (58 ° C.), the conduction and blocking of the switching element TR1 configured in the inverter means 102 is controlled and the second soak set time t12 is determined. Will be maintained until

Thereafter, when the internal temperature of the metal fan 110 reaches the bite temperature and the second set time t12 elapses, the duty ratio of the conduction / interruption time of the switching element TR1 is set to 13: 3, that is, the duty is set to 14 levels. By performing the cooking process in the same manner as described above (ST113) and when the cooking process is completed to perform the moxibustion process.

In addition, if the reservation time t1 read through the timer as a result of the search in step ST102 is equal to or greater than the second reservation setting time t3: 6 hours, the system control means 112 performs cooking without calling set time. In step (ST110), the duty ratio is set to 12: 4, that is, the duty is set to 12 levels (ST111), and the cooking process ST114 is performed in the same manner as described above, and the cooking process is performed when the cooking process is completed.

In conclusion, it reads the time from the current time to the reservation time and controls the duty ratio and time within that time, that is, if the time is short, the call setup time and duty ratio are taken large, and if the time is long, the call setup time is short and the duty The rain is kept low so that it can have an even distribution of heat in the actual heating to prevent the unripe of the rice and to control the optimum state so that it does not become a layered rice.

As described in detail above, according to the present invention, the optimum cooking is performed by preventing the unripement of the rice generated at the time of reserved cooking and having the even heat distribution and the water content of the rice, as well as the convenience of the induction heating rice cooker by proper use of the reserved cooking. In addition, the longer the time control and the reservation time, the shorter the soaking time and the lower the duty, which is parallel to the temperature rise of the lower temperature sensing member. Giving effect.

Claims (7)

Counting the reservation time in the reservation cooking mode and comparing and searching the first and second reservation setting times; Performing a soaking process by varying the soak setting time according to a comparison result between the reservation time and the first and second reservation setting times; And performing a cooking process by proportionally setting the duty according to the set soak setting time. 2. The method of claim 1, wherein the first reservation setting time is 3 hours and the second reservation setting time is 6 hours. The method of claim 1, wherein if the reservation time is less than or equal to the first reservation setting time, the soak setting time is set to 20 minutes. The method according to claim 1, wherein when the reservation time is greater than or equal to the first reservation setting time and less than or equal to the second reservation setting time, the soak setting time is set to 10 minutes. The method according to claim 1, wherein when the reservation time is greater than or equal to the second setting time, the cooking process is performed at a duty level of 12 without a soaking setting time. 4. The method according to claim 1 or 3, wherein when the soak setting period is 20 minutes, the cooking process is performed at a duty level of 16. The method according to claim 1 or 4, wherein when the soak setting time is 10 minutes, the cooking process is performed at a duty level of 14, wherein the cooking process of the electromagnetic induction heating rice cooker is performed.