JPH0216556Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a cooking device that heats and cooks food using a heater.

[Conventional technology]

Generally, when cooking food in an oven using a cooking device such as an electric oven equipped with a heater whose operation is controlled by a microcomputer, etc., depending on the type of food, it is necessary to optimize the finish of the food. , to reduce cooking time,
There are cases where it is necessary to preheat the interior of the cooking chamber to a high temperature prior to cooking, and preheating in conventional cooking devices is performed, for example, in a procedure as shown in the flowchart of FIG.

That is, as shown in FIG. 4, after inputting a preheating instruction by operating a setting means such as a keyboard provided on the front operation panel of the apparatus main body, a desired preheating temperature Tp is set by the setting means, and the setting is performed. When the start key of the means is turned on, a control means such as a microcomputer provided in the device starts energizing the heater, turns on the heater, heats the inside of the cooking chamber, and heats the inside of the cooking chamber. The control means determines whether the internal temperature Td detected by the internal temperature detection means such as a thermistor is equal to or higher than the preheating temperature Tp;
If the determination is NO, energization to the heater is continued; if the determination is YES, energization to the heater is interrupted and the heater is turned on and off;
At the same time as the temperature inside the cooking chamber is maintained at the preheating temperature Tp, the alarm sound generating means is driven by the control means as the temperature inside the cooking chamber reaches the desired preheating temperature Tp, and the generating means generates an alarm. A sound is generated and output, and then the control means determines whether or not the door which can be freely opened and closed in the cooking chamber is opened, and if the determination is YES, the power supply to the heater is stopped and the The heater is turned off and preheating is completed and the device enters a standby state, and if the determination is NO, the operation following the comparison determination between the internal temperature Td and the preheating temperature Tp by the control means is repeated.

[Problem that the invention attempts to solve]

However, in this type of cooking device, when the door is opened to store the food to be cooked, the power supply to the heater is stopped, so when the door is opened, the hot air inside the cooking chamber escapes to the outside. Even if the temperature inside the preheated cooking chamber drops and the door is closed and the heater starts cooking the food in the oven, the temperature inside the cooking chamber is equal to the preheating temperature Tp. There are problems in that it takes time to reach the desired temperature and the cooking time becomes longer, so that the food to be cooked is not finished in an optimal state.

Therefore, the applicant has previously proposed a cooking device (Japanese Patent Application Laid-open No. 166888/1988) that preheats the cooking area prior to cooking, similar to the cooking device described above. After a certain period of time, for example
If there is an operation to start cooking or heating the food within 15 minutes, or if there is no operation, the system will move to cooking and heating,
Alternatively, the preheating is stopped after the predetermined period of time has elapsed to prevent the cooking appliance from being left in the preheated state, but it is not intended to suppress the temperature drop in the cooking chamber due to opening of the door.

[Means for solving problems]

This invention was made with the above points in mind, and is intended to suppress the drop in preheating temperature inside the cooking chamber due to the opening of the door. a heater for heating the food; a setting means for inputting settings for cooking conditions such as cooking temperature and cooking time of the object to be cooked; and preheating temperature;
a cooking control means for cooking the food by controlling the operation of the heater according to the set cooking conditions; and a cooking control means for controlling the operation of the heater until the door is opened prior to the cooking of the food by the cooking control means. The cooking device includes a preheating control means for preheating and maintaining the interior of the cooking chamber at the preheating temperature, and a continuation means for detecting opening of the door and continuing operation of the heater for a predetermined period of time.

[Effect]

Therefore, in this invention, the preheating control means controls the operation of the heater until the door is opened before the cooking control means starts cooking the food to be cooked. The opening of the door for storing items in the cooking cabinet is detected by the continuation means, and the operation of the heater is forcibly continued for a predetermined period of time from the opening of the door.

〔Example〕

Next, a description will be given of FIGS. 1 to 3 showing an embodiment in which this invention is applied to a convex type microwave oven.

First, in FIG. 1 showing a cross section of a microwave oven, 1 is formed inside the microwave oven by a partition wall 1', and the opening of the front partition wall 1' is closed by a door (not shown). cooked kitchen,
Reference numeral 2 denotes an object to be cooked placed on a mounting table 3 provided at the bottom of the cooking chamber 1; 4 a heater case provided at the upper end of the cooking chamber 1 and forming a heater storage section 5; 6;
7 is a magnetron provided between the microwave oven body and the partition wall 1', and 7 is a conductor whose both ends are connected to the output part of the magnetron 6 and to the approximately central part of the upper partition wall 1', and whose inside is connected to the storage section 5. A wave tube 8 is a coil-shaped heater disposed in the storage section 5 and runs along the inner circumference of the case 4; 9 is a drive pulley provided above the center of the upper partition wall 1' and driven by a motor; 1;
Reference numeral 0 indicates a rotating shaft which is rotatably inserted through the upper partition wall 1' and whose upper end is fixed to the pulley 9; The waveguide 7 is pivotally attached to the lower end.
While stirring the microwaves from the magnetron 6 via the heater 8, hot air from the heater 8 is circulated inside the cooking chamber 1.

Reference numeral 12 denotes a fan case made of ceramics that is joined to the lower end of the heater case 4 to close the storage section 5 and prevent the human body from touching the heater 8, and communicates the storage section 5 and the cooking chamber 1 in the central part. Storage part 5
A circular suction hole 12a is transparently provided, and
A plurality of fan-shaped holes 12b for blowing out hot air are transparently provided in a portion corresponding to the lower part of the heater 8.

Next, FIG. 2 showing circuit connections will be explained.

In FIG. 2, 13a and 13b are first and second power supply terminals connected to a commercial power supply, 14 is a fuse whose one end is connected to the first power supply terminal 13a, and 15
Reference numerals a and 15b are first and second interlock switches each having one end connected to the other end of the fuse 14 and the second power supply terminal 13b, and 16 an interlock switch having both ends connected to the other ends of both interlock switches 15a and 15b. A lock monitor switch 17 has one end connected to the other end of the first interlock switch 15a and is activated when the magnetron generates heat above a predetermined temperature. 18 has both ends connected to the other end of the first thermostat 17. and a second heater which is connected to one end of the heater 8 and is activated when the heater 8 generates heat above a predetermined temperature.
The thermostat 19 is a high-voltage transformer in which one end of the primary coil 19a is connected to the other end of the first thermostat 17, and the magnetron 6, rectifier diode, high-voltage capacitor, etc. are connected to both ends of the secondary coil 19b and an intermediate tap. A magnetron oscillation circuit is connected.

20a and 20b are connected to the heater 8 and the magnetron 6, in which one anode is connected to the other end of the heater 8 and the other end of the primary coil 19a, and the other anodes are both connected to the other end of the second interlock switch 15b. The first and second triaxes 21a and 21b for power supply control are provided between the gates of the first and second triaxes 20a and 20b and the other anode, respectively, and are the first and second capacitors for preventing malfunction due to voltage surges; Both ends of the primary coil 22a are connected to the first and second power terminals 13a,
A control transformer 13b is connected to the control transformer, and 23 is a microcomputer (hereinafter referred to as a microcomputer) whose power terminal is connected to the secondary coil 22b of the transformer 22.
The output terminal of the keyboard 24, which is a setting means, is connected to the data input terminal of the microcomputer 23,
Both ends of a thermistor 25 that detects the internal temperature of the cooking chamber 1, and a door switch 26 that turns off and on according to the opening and closing of the door that freely opens and closes the cooking chamber.
is connected to the signal input terminal of the microcomputer 23, and the gates of both triaxes 20a and 20b are connected to the control signal output terminal of the microcomputer 23, and the microcomputer 23 controls the magnetron 6 and Both triaxes 20a, 2 are used to control the operation of the heater 8.
Cooking control means outputs a gate control signal to the gate 0b, and when a preheating instruction is set by the keyboard 24, a gate control signal is sent to the gate of the first triax 20a to control the operation of the heater 8 until the door is opened prior to cooking. The preheating control means outputs a gate control signal to the gate of the first triax 20a in order to detect the opening of the door due to the switch 26 being turned off and to continue the operation of the heater 8 for a predetermined period of time, and also outputs a gate control signal to the gate of the first triax 20a.
It is designed to operate as a continuation means for keeping the circuits a and 15b on.

Next, the operation when preheating is performed prior to oven cooking using only the heater 8 will be explained with reference to the flowchart shown in FIG.

First, as shown in FIG. 3, a preheating instruction is input by operating keys on the keyboard 24 in step S1, and a desired preheating temperature Tp is set by operating keys on the keyboard 24 in step S2. When the start key is turned on, in step S4,
A gate control signal is output from the microcomputer 23 to the first triax 20a.
is turned on, energization to the heater 8 is started via both the interlock switches 15a, 15b, which are in the on state, and the first triax 20a, the heater 8 is turned on, and the inside of the cooking chamber 1 is heated, and then in step S5, The microcomputer 23 determines whether or not the internal temperature Td detected by the thermistor 25 is equal to or higher than the preheating temperature Tp. If the determination is NO, the process returns to step S4 to continue energizing the heater 8, and the determination is completed. If YES, the process moves to step S6, and the microcomputer 23 sends the first tryack 20a.
The power supply to the heater 8 is interrupted by the gate control signal to turn the heater 8 on and off, and at the same time, the temperature inside the cooking chamber 1 is maintained at the preheating temperature Tp.
When the internal temperature of the cooking cabinet 1 reaches the desired preheating temperature Tp, the microcomputer 23 synthesizes and outputs an alarm sound, and in step S7, the microcomputer 23 determines whether the door is opened based on whether the door switch 26 is turned on or off. A determination is made whether or not.

Then, the determination in step S7 is NO.
If so, return to step S5 again and use the microcomputer 23.
The above-mentioned comparison judgment between the internal temperature Td and the preheating temperature Tp is repeated, and if the judgment in step S7 is YES, the process moves to step S8, and the timer as a continuation means of the microcomputer 23 starts counting the time Δt. At the same time, the microcomputer 23 turns on the heater 8 again in step S9.
energization is started and the heater 8 is turned on, and then, in step S10, the microcomputer 23 determines whether the count time Δt of the timer has reached the initial set time Δts, which is the continuous operation time of the heater 8. , the determination in step S10 is
If YES, the process moves to step S11, where the microcomputer 23 stops energizing the heater 8 and turns off the heater 8, and at the same time, the microcomputer 23 synthesizes and outputs an alarm sound, indicating that the heater 8 has been turned off. A notification is given, and in step S12, preheating is completed and the oven enters a standby state to start cooking.

On the other hand, if the comparison judgment between the count time Δt and the set time Δts in step S10 is NO, the process moves to step S13, where the microcomputer 23 determines whether the door is opened again based on whether the door switch 26 is turned on or off. and step S
If the determination in step S13 is YES, it is determined that the door remains open and the process returns to step S9. If the determination in step S13 is NO, the door is closed by the time the count time Δt by the timer reaches the set time Δts. The preheating is terminated in step S14 as the heater 8 is closed, and the oven cooking of the food to be cooked 2 by continued operation of the heater 8 is immediately started, thereby bringing the preheating routine to an end.

At this time, in step S14, even if oven cooking is started, the microcomputer 23 as a continuation means continues to energize the heater 8 until the count time Δt of the timer reaches the set time Δts, and the heater 8 is continuously energized for the count time Δt. Δt is the set time Δts
At the point in time, the microcomputer 23 serving as the cooking control means continuously switches to energizing the heater 8.

In addition, in the case of microwave cooking using only the magnetron 6 or cooking using a combination of the magnetron 6 and the heater 8, the microcomputer 23 sends the second tryack 2.
0b only or both triaxes 20a, 20b
The gate control signal output to the gate of the second triax 20b or both triaxes 2
0a and 20b are controlled, and the microcomputer 23 controls the operation of the magnetron 6 and heater 8 according to the cooking conditions set by the keyboard 24.
is cooked.

In addition, in the above example, the case where it was applied to a convex type microwave oven was explained.
Of course, it can be applied to electric ovens.

[Effect of idea]

As mentioned above, according to the cooking device of this invention,
When preheating the inside of the cooking chamber 1 prior to oven cooking using only the heater 8, the food to be cooked 2 is stored in the cooking chamber 1 after the internal temperature of the cooking chamber 1 reaches a desired preheating temperature. Even if the door is opened, the microcomputer 23 energizes the heater 8 for a predetermined period of time after the door is opened, and the heater 8 continues to operate, so that a drop in the preheated internal temperature of the cooking cabinet 1 is suppressed. The finished product 2 to be cooked in the oven can be optimally finished and the cooking time can be shortened, and the effect is remarkable.

[Brief explanation of drawings]

Figures 1 to 3 show one of the cooking devices of this invention.
An example is shown in which FIG. 1 is a sectional view, FIG. 2 is a wiring diagram, FIG. 3 is a flowchart for explaining the operation, and FIG. 4 is a flowchart for explaining the operation of a conventional cooking device. 1... Cooking cabinet, 2... Food to be cooked, 6... Magnetron, 8... Heater, 23... Microcomputer, 24... Keyboard.

Claims (1)

[Scope of utility model registration request] A heater for heating food to be cooked stored in a cooking cabinet that is openable and closed by a door, a setting means for inputting settings for cooking conditions such as cooking temperature and cooking time for the food to be cooked, and preheating temperature; cooking control means for cooking the food by controlling the operation of the heater according to the cooking conditions; and cooking control means for controlling the operation of the heater until the door is opened prior to the cooking of the food by the cooking control means. A cooking device comprising a preheating control means for preheating and maintaining the interior of the refrigerator at the preheating temperature, and a continuation means for detecting opening of the door and continuing operation of the heater for a predetermined period of time.