JPH03168529A - Microwave oven - Google Patents

Abstract

PURPOSE:To prevent excessively high temperature of an article to be heated at the time of heat insulation by composing to drive a magnetron in an intermittently driving mode set based on weight detection result of the article to be heated to execute heat insulation. CONSTITUTION:A weight sensor 8 for detecting the weight of an article to be heated, and driving mode setting means 7 for setting the intermittently driving mode of a magnetron 4 in response to the weight detection result by the sensor 8 are provided, and the magnetron 4 is driven by the set mode to execute heat insulation. with this structure, since the sensor 8 detects the weight of the article to be heated and the driving mode of the magnetron is set in response to the weight detection result, heating power responsive to the weight of the article to be heated can be set. Accordingly, the magnetron 4 is intermittently driven by this mode to execute heat insulation to prevent excessively high temperature of the article to be heated.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a microwave oven having a melon preserving function.

(Prior art) In a microwave oven, an object to be heated is heated and cooked by microwaves emitted from a magnetron.
Some devices are designed to keep warm after cleaning.

Therefore, as a heat retention method, a feedback control method can be considered in which a temperature sensor is provided in the heating cooking chamber and the drive of the mug fastener is controlled based on the temperature detection result by this temperature sensor. However, this method requires a temperature sensor, and the microwave oven requires the user to take out the heated item relatively quickly after cooking, and furthermore, if the microwave oven is kept warm for an extended period of time, the heated item will become dehydrated. For reasons such as the risk of heat retention, conventional heat retention methods do not use an a-degree sensor, but instead set the magnetron drive pattern to an intermittent drive pattern suitable for heat retention, and set the heat retention time to a fixed time in advance. The heat retention time is determined, and the heat retention time is determined so that the temperature is intermittently driven. The driving situation of the magnetron in this case is as shown in FIG. This product does not require a temperature sensor, so costs can be reduced.
In addition, it is rare for pigeons to become dehydrated.

(35 When the amount of the heated material is small, the temperature of the heated material may rise too much at the end of the warming period, as shown by curve B in FIG.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a microwave oven that does not cause the mixture of the heated melon to become excessively high when preserving the melon after the end of cooking. .

[Structure of the Invention] (Means for Solving the Problems) The present invention cooks an object to be heated using microwaves emitted from a magnetron, and after cooking, intermittently drives the magnetron to keep the object warm at a predetermined value. A weight sensor for detecting the weight of the object to be heated and a drive mode setting means for setting an intermittent drive mode of the magnetron in accordance with the weight detection result by the weight sensor are provided. The feature is that the magnetron is driven in this set drive mode to perform heat retention.

(Function) The weight sensor detects the weight of the object to be heated. The drive mode setting means then sets the magnetron drive mode according to the weight detection result. Therefore, the heating power is set according to the weight of the object to be heated. Therefore, by intermittently driving the magnetron in this drive mode to maintain heat, the temperature of the object to be heated will not rise excessively.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

First, in FIG. 1 schematically showing the basic structure, the housing 1
A heating cooking chamber 2 is formed inside the heating cooking chamber 2, and a saucer 3 on which heated items are placed is disposed inside the heating cooking chamber 2. The magnetron 4 oscillates microwaves and supplies them into the heating cooking chamber 2 to heat and cook the food to be heated. This magnetron 4 is driven by a drive unit 5 equipped with a high voltage transformer, a voltage doubler rectifier circuit, etc. This drive unit 5 is controlled to be turned on and off by a relay 6, and this relay 6 is controlled by a microcomputer. On/off control is performed by a control circuit 7 that includes the control circuit 7.

That is, the magnetron 4 is driven and controlled by the control circuit 7. The weight sensor 8 detects the weight of the heated object placed on the saucer 3, and the weight detection result is provided to the control circuit 7 via the sensor circuit 9. Further, the gas sensor 10 detects gas such as steam generated from an object to be heated, and the detection result is provided to the control circuit 7 via the sensor circuit 11. A switch operating section 12 and a display 13 are provided as peripheral devices for the control circuit 7, and the switch operating section 12 includes a start switch.
Equipped with menu switches, etc.

When the start switch is operated, the control circuit 7
The magnetron 4 is continuously driven to carry out heating cooking operation. In this case, heating cooking is terminated on the condition that the amount of gas released from the gas sensor 10 reaches a predetermined value. The control circuit 7 is configured to drive and control the magnetron 4 intermittently during heat retention, and its drive mode is set in accordance with the weight detection result.

The operation of the above configuration will be explained with reference to the control function of the control circuit 7 as well as FIGS. 2 and 3. Fig. 2 shows ffil1 related to cooking and keeping warm. A flowchart of the contents of the 8 program is shown, and this control program is started when the start switch is turned on.

Further, FIG. 3 shows an example of the drive mode of the magnetron 4.

Then, when the start switch is turned on, the detection results from the weight sensor 8 are read (Stezop S1),
If the detection result is "r400g or less" (step S
2) The drive time α in the intermittent drive mode of the magnetron 4 is set to α1, and the rest time β is set to β1 (step S3).

Further, if the weight detection result is "r over 400 g and less than 1000 g" (step S4), the drive time in the intermittent drive mode (2 is set as α2 and the rest time β is set as β2 (step S5)) If so, the drive time a is set to α, and the pause period (2) and 1f period β is set to β (step S6).

Here, the α relationship between α1, 2, α3, β1, β2, and β3 is the relationship α, × α2 × α,, β1>β2>β3 (
(See Figure 3). In other words, the driving time α is set to be shorter and the rest time β is set to be longer as the weight of the object to be modified is smaller.

After setting such a drive mode, the magnetron 4 is continuously driven (step S7) to start cooking. Then, if a heating cooking end command is issued based on the detection result from the gas sensor 10 reaching a predetermined value (step S8).
, the drive of the magnetron 4 is stopped (step S9), and the heating cooking is completed.

Thereafter, the magnetron 4 is intermittently driven in the drive mode set above to perform heat retention (step S10).
. When this elapsed time reaches a preset heat retention time (step S11), the intermittent drive of the magnetron 4 is stopped (step S12), and the heat retention is ended.

In this way, the drive mode of the magnetron 4 is unique! Since the magnetron drive mode is set according to Iim, the heating force is set according to the weight of the object to be heated. Therefore, in this drive mode, the magnetron 4
As can be seen from FIG. 4, by intermittently driving the heater to maintain heat, the temperature of the object to be heated will not rise excessively. Figure 4 shows the temperature of the heated object during heat retention, where curve G shows the case of a heated object with a small weight, and curve H shows the case of a heated object with a large weight. ing.

In addition, in the driving mode of the magnetron 4, the time values α1, α2, α3, β1, β2, β,
However, a slight correction may be made depending on the type of food being heated (stew, rice, etc.). In this case, the correction may be made in accordance with the operation of the menu switch. In this case, overheating prevention can also be expected depending on the type of object to be heated.

In addition, the present invention is not limited to the above embodiments,
Various modifications may be made without departing from the spirit of the invention.

[Effects of the Invention] As is clear from the above description, the present invention cooks an object to be heated using microwaves emitted from a magnetron, and after cooking, intermittently drives the magnetron to keep the object warm. A weight sensor for detecting the weight of the object to be heated, and a drive mode setting means for setting an intermittent drive mode of the magnetron according to the weight detection result by the weight sensor, The device is characterized in that the magnetron is driven in this set drive mode to carry out the heat retention, which prevents the temperature of the heated object from becoming excessively high during the heat retention after the completion of heating. It has the effect of never happening.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, FIG. 1 is a schematic configuration diagram, and FIG. 2 is a Ril1? FIG. 3 is a diagram showing an example of the drive mode of the magnetron, and FIG. 4 is a diagram showing temperature changes during heat retention. FIG. 5 and FIG. 6 are equivalent to FIG. 3 and FIG. 4 showing the conventional example. In the figure, 2 is a heating chamber, 5 is a drive unit, and 7 is a control circuit (
drive mode setting means), 8 is a melon sensor, ]0 is a gas sensor.

Claims (1)

[Claims] 1. An object to be heated is cooked by microwaves emitted from a magnetron, and after cooking, the magnetron is intermittently driven to keep the object warm for a predetermined period of time, and the weight of the object to be heated is A weight sensor for detecting the weight and a drive mode setting means for setting the intermittent drive mode of the magnetron according to the result of weight detection by the weight sensor are provided, and the magnetron is driven in the set drive mode to perform heat retention. A microwave oven characterized by: