JPH0690864A - Thermaol cooking apparatus - Google Patents

Abstract

PURPOSE:To enable the thawing of frozen foods as in a short time as possible maintaining taste at a level almost equal to that in natural thawing by providing a heating selection means which allows the selection of heating for cooking- heating a cooking plate at a high temperature and heating for thawing-heating at a low temperature to keep the foods at a fixed temperature. CONSTITUTION:A cooking plate 2 is provided at an upper part of a cooker body 1, a heater 3 on the undersurface side thereof and a thermistor 4 to detect the temperature of the cooking plate 2. Moreover, an electric circuit 26 is provided in the cooker body 1 and also serves as heating selection means to select heating for cooking and heating for thawing. In other words, with an input from a key input circuit 29, a temperature data of the thermistor 4 is inputted into a microcomputer 27 from a temperature detection circuit 28 to control a relay RL. Power is supplied to the heater 3 from an AC power source P while a contact (r) is opened or closed depending on an output level to the base of a transistor Q from the microcomputer 27 thereby conducting or cutting a current from a coil L to the heater 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device such as a hot plate.

[0002]

2. Description of the Related Art As a method for thawing frozen food in a general household, low temperature thawing at about 5 ° C. in a refrigerator,
The mainstream is natural thawing performed in a room at room temperature or microwave thawing. Recently, thawing plates made of aluminum have also been used. This uses the size of the heat capacity of the plate made of aluminum, put frozen food on this plate, in a state close to natural thawing,
Moreover, it is intended to perform thawing in a shorter time.

[0003]

It is generally said that cooked frozen foods and frozen vegetables are preferably thawed quickly, but raw frozen foods such as fish and meat are It is said that it is preferable to thaw slowly in order to suppress the action as much as possible and to reduce the outflow of juice.
Therefore, for thawing raw frozen foods, low-temperature thawing in a refrigerator is preferable because it causes the least change in flavor, but has a drawback of taking too much time. In addition, even natural thawing takes too much time. On the other hand, in the case of thawing in a microwave oven, although it takes only a short time, the taste is greatly deteriorated and sometimes the food is locally boiled. Among the conventional thawing methods, the method of thawing with an aluminum thawing plate causes less change in flavor as in the case of natural thawing and requires a relatively short time. For example, 2
When thawing 00g of meat, it takes about 90 minutes,
Even so, the waiting time to start cooking is quite long.

Therefore, using a hot plate which is a heating cooker having the same aluminum cooking plate,
It is considered that the cooking plate on which the frozen food is placed is thawed while being heated by a heater. In the hot plate, conventionally, the temperature of the cooking plate is detected by a temperature detection element, and the temperature of the cooking plate can be controlled by inputting this to a microcomputer to control energization of a heater. . However, the lowest temperature setting in a conventional hot plate is at best
The temperature is around 80 ° C, and even at this minimum setting temperature, thawing becomes too fast, and it is difficult to thaw frozen food uniformly, and the outer surface of the food is burned.

The present invention has been made in consideration of such circumstances, and it is also possible to thaw frozen foods such as raw foods, and at this time, while maintaining a flavor almost equal to that of natural thaw,
It is an object to provide a heating cooker that can be thawed in the shortest possible time.

[0006]

The cooking device according to the present invention comprises:
To achieve the above object, a cooking plate, heating means for heating the cooking plate, cooking heating for heating the cooking plate at a high temperature and heating at a lower temperature for about 20
And a heating selection means for selecting heating for thawing that is maintained at about -30 ° C.

[0007]

In the heating cooker of the present invention, during heating, the heating selection means selects the heating for cooking, the food is placed on the cooking plate, and the cooking plate is heated at a high temperature. On the other hand, when thawing raw frozen foods, heat for thawing is selected by the heating selection means, the frozen foods are placed on the cooking plate, and the cooking plate is heated at a low temperature by the heating means to about 20 to 30 ° C. keep.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the heating cooker according to the present invention will be described below with reference to the drawings. The heating cooker of this embodiment is a so-called hot plate. In FIG. 3, reference numeral 1 is a cooker body, and an aluminum cooking plate 2 is provided on the cooker body 1. A heater 3 as a heating means for heating the cooking plate 2 is provided on the lower surface side of the cooking plate 2, and a thermistor 4 which is a heat sensitive element for detecting the temperature of the cooking plate 2 is provided. It is provided.

Further, the outer surface of the cooker body 1 is shown in FIG.
A display panel 11 is provided as shown in FIG. The display panel 6 is provided with temperature setting switches 12, 13, 14, 15 for 260, 200, 140, 80 ° C., an off switch 16 and a defrosting switch 17, and each switch 12 except the off switch 16. , 13, 14, 15, 17 are provided with display lamps 18, 19, 20, 21, 22 respectively. The switches 12, ..., 17 are all push button switches. Then, by pressing any one of the temperature setting switches 12, 13, 14, 15, the corresponding display lamp 18, 19, 20,
When 21 is turned on, heating for cooking by the heater 3 is started and the temperature of the cooking plate 2 is about 260 and 20 respectively.
The temperature of the cooking plate 2 is controlled at 0, 140, 80 ° C, and when the defrosting switch 17 is pressed, the corresponding indicator lamp 22 lights up, and the heating of the defrosting by the heater 3 is started, so that the temperature of the cooking plate 2 is room temperature, that is, about 30 ° C. It is designed to be kept to a certain degree. Further, if the off switch 16 is pressed at an arbitrary time point, the display is turned off, the display lamps 18, ..., 22 are turned off, and the heater 3 is always turned off.

Further, an electric circuit 26 as shown in FIG. 1 is provided in the cooker main body 1. This electrical circuit
The reference numeral 26 also serves as heating selection means for selecting the heating for cooking and the heating for thawing. A contact r of the relay RL and the heater 3, which is a heating element, are connected in series between both electrodes of an external 100V commercial AC power source P. Further, a transistor Q and a coil L of the relay RL are connected in series between both poles (Vcc, GD) of a DC power source obtained by rectifying and smoothing the AC power source P, and the base of the transistor Q is a microcomputer. It is connected to 27 output ports via a resistor R. Further, a temperature detection circuit 28 including the thermistor 4 is provided at an input port of the microcomputer 27.
, And a key input circuit 29 including the switches 12, ..., 17 are connected. The microcomputer 27 is
The DC power source is used as a power source.

Next, the operation of the above configuration will be described. First, the usage method will be described. When performing normal heating and cooking, the food to be cooked is placed on the cooking plate 2 and any one of the temperature setting switches 12, 13, 14, and 15 suitable for the food to be cooked and the contents of cooking is pressed. Along with this, the heater 3 generates heat and the food on the cooking plate 2 is heated. At this time, the temperature of the cooking plate 2 is 260, 200, 14 selected by the temperature setting switches 12, 13, 14, 15.
It is maintained at either 0 or 80 ℃. When thawing raw frozen food, the frozen food is placed on the cooking plate 2 and the thawing switch 17 is pressed.
Along with this, the heater 3 intermittently generates heat, and the frozen food on the cooking plate 2 is heated and thawed. At this time,
The temperature of the cooking plate 2 is kept at about 30 ° C.

Next, the control of the heater 3 will be described. First, by inputting from the key input circuit 29 in response to the operation of the switches 12, ..., 17, the microcomputer 27 switches and sets several stages of temperature control for cooking heating and thawing heating. And
The temperature data of the thermistor 4 for detecting the temperature of the cooking plate 2 is input from the temperature detection circuit 28 to the microcomputer 27 as a voltage value, for example, and is A / D converted. Compared to the value selected via 29. Then, this comparison is processed in the microcomputer 27, and the drive of the relay RL is controlled based on the processing. Electric power is supplied to the heater 3 from the AC power supply P through the closed contact r of the relay RL, but when the output from the microcomputer 27 to the base of the transistor Q is low level, the coil L of the relay RL is supplied. When a current flows and the contact r is closed and the output to the base of the transistor Q is at a high level, no current flows in the coil L, the contact r is opened, and the heater 3 is cut off. Note that the configuration itself of such a temperature control circuit is general.

Next, the heater 3 at the time of heating for thawing
The control of will be described in detail. First, when the thawing switch 17 is pressed in the stopped state, the thawing heating routine shown in FIG. 5 starts. In this thawing heating routine, first, high temperature determination (step S1) is performed. That is, the detected temperature T of the cooking plate 2 and the high temperature determination set temperature HT (50
℃) is compared, and if T ≧ HT, a buzzer or the like notifies the user (step S2) and returns to the stopped state (step S2).
S3). That is, when the temperature of the cooking plate 2 is 50 ° C. or higher, the thawing is rejected, and the user is informed that the thawing is rejected by the notification by the buzzer and the display lamp 22 not lighting. On the other hand, if T <HT, the indicator lamp 22 is turned on (step S4), and it is informed that the heating for thawing has started. Next, the detected temperature T of the cooking plate 2 and the set temperature RT for control (30 ° C.) are compared (step S5), but the heater 3 is not energized as long as T ≧ RT. On the other hand, when T <RT, first, the first timer which is timed up at the preset time t1 is started (step S6), and the heater 3 is energized (step S7). Then, it is determined whether or not the first timer has timed out, that is, whether or not t1 has elapsed since the start of the first timer (step S8),
If t1 has not passed, the process returns to step S7, and the heater 3 continues to be energized. On the other hand, when t1 has passed, a second timer that times up at a preset t2 time starts (step S9), and the heater 3 is cut off (step S10). Then, it is determined whether or not the second timer has timed out, that is, whether or not t2 has elapsed from the start of the second timer (step S11).
), If t2 has not passed, the process returns to step S10 and the heater 3 continues to be cut off. On the other hand, if t2 has passed, the process returns to the determination in step 5. Note that t1 is significantly shorter than t2. Thus, while the temperature of the cooking plate 2 is 30 ° C. or lower, the energization rate control to the heater 3 is performed, the temperature of the cooking plate 2 reaches 30 ° C., and then the energization of the heater 3 is constantly stopped. Thereby, the temperature of the cooking plate 2 is maintained at about 30 ° C. Note that FIG. 6 shows the relationship between the input control of the heater 3 and the temperature of the cooking plate 2. Although not shown in the flowchart of FIG. 5, in the thawing heating routine, the elapsed time from the start of this routine and the presence / absence of operation of the off switch 16 are determined, and the elapsed time exceeds the set time. When the time is up, or when the off switch 16 is pressed, the heater 3 is stopped and the heater 3 is always cut off.

It should be noted that FIG. 4 shows a transitional relationship between the normal cooking heating operation, the stopped state, and the thawing heating operation. As shown in the figure, even if the defrosting switch 17 is pressed, the normal cooking heating operation cannot be directly transferred to the defrosting heating operation, and if the temperature of the cooking plate 2 is not sufficiently lowered, Cannot move to heating operation.

As described above, according to the configuration of the above-mentioned embodiment, the thawing can be performed by the hot plate for heating and cooking. Moreover, when thawing, the cooking plate 2
Since the temperature is controlled around 30 ° C, which is the normal temperature, when thawing raw frozen food such as fish and meat, it can be thawed quickly while maintaining the same flavor as natural thawing. As an example, the following experimental results were obtained regarding the thawing time when 200 g of frozen meat was thawed. That is, when the room temperature is 20 ° C., the set temperature during thawing in this example is 30 ° C., the heater 3 is 1300 W, and the electric conductivity is 5%, this example takes about 30 minutes, and the conventional thawing plate has about 30 minutes.
90 minutes, about 120 minutes or more with natural thawing.

Further, recent hot plates have become high power, and for example, the heater 3 has become about 1300 W. Moreover, the temperature control range of the cooking plate in the conventional hot plate is at most 80-2.
Since the temperature is around 60 ° C and there is no need or need to control the temperature of the cooking plate at room temperature, the heater controls the electrical connection and disconnection simply according to the detected temperature. However, since the power is high, the temperature rises too much, and it is impossible to control the temperature of the cooking plate at room temperature by simply switching on and off according to the detected temperature. On the other hand, in the hot plate of the present embodiment, as described above, the on-off cooking plate 2 can be formed by using both the on / off control during the normal cooking heating and the duty ratio control during the thaw heating. It becomes possible to control the temperature to room temperature, and it is possible to thaw without losing the flavor.

In addition, if the cooking plate 2 is thawed while the temperature of the cooking plate 2 is still high after another cooking, the frozen food which should be naturally thawed will be burned. In the example, when the high temperature is determined and the temperature of the cooking plate 2 is unsuitable for thawing, the thawing is rejected even if the defrosting switch 17 is pressed. It is possible to prevent it from directly touching and locally boiling. The set temperature for high temperature judgment HT = 50 ° C is the set temperature for control RT
The temperature is slightly higher than 30 ° C., and is set as a temperature at which the frozen food does not become raw when the frozen food is placed on the cooking plate 2. Moreover, since the normal heating operation for cooking cannot be directly transferred to the heating operation for thawing and the thawing does not occur unless the operation is always returned to the stopped state, the high temperature determination is always applied.

The present invention is not limited to the above embodiment, but various modifications can be made. For example,
In the above embodiment, the same heater 3 that is used during normal cooking is also used for defrosting heating by controlling the energization rate. However, the energizing rate control is not performed and a heater for cooking is used. Separately, a low power heater may be provided for thawing heating. However, the cost is high if the heater is separately provided in this way. In addition, the thermistor that detects the temperature of the cooking plate generally has a narrow application temperature range.Therefore, a thermistor for high temperature used for heating for cooking and a thermistor for low temperature used for heating for thawing. May be separately provided.

[0019]

According to the present invention, in the heating cooker for heating the cooking plate by the heating means, in addition to the cooking heating for heating the cooking plate at a high temperature, it is heated at a lower temperature to about 20 to 30 ° C. Since it is possible to selectively perform heating for thawing, frozen food such as fish and meat can be thawed, and at this time, it can be thawed in the shortest possible time while maintaining the flavor almost equal to that of natural thawing. .

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of a heating cooker according to the present invention.

FIG. 2 is a front view of the same operation and display panel as above.

FIG. 3 is a sectional view of the same as above.

FIG. 4 is a state transition diagram of the above.

FIG. 5 is a flowchart of the above.

FIG. 6 is a timing chart of the above.

[Explanation of symbols]

 2 Cooking plate 3 Heater (heating means) 26 Electric circuit (heating selection means)

Claims (1)

[Claims] 1. A cooking plate, heating means for heating the cooking plate, cooking heating for heating the cooking plate at a high temperature, and thawing heating for heating at a lower temperature to keep at about 20 to 30 ° C. are selected. A heating cooker, comprising: