JPS59133441A - Cooking apparatus with infrared sensor - Google Patents

Abstract

PURPOSE:To prevent abnormal cooking by making a comparison between outputs of plural infrared sensors provided on the reverse side of the ceiling surface of a heating chamber, and deciding on output abnormality of each infrared sensor. CONSTITUTION:An infrared sensor unit 6 has plural infrared sensors on the reverse side of the ceiling surface of the heating chamber 2. A main control part 15 incorporating a microcomputer makes a comparison between outputs of the infrared sensors 6a1 and 6a2 supplied through a sensor output processing circuit 16 and detects the temperature of food to be cooked on the basis of the mean value of each infrared sensor. Then, on-off control over a switch 11 and conduction control over a triac 12 are performed according to the detected temperature and a cooking program previously set by an operation part 17. If it is judged that the output of the infrared sensor 6a1 or 6a2 is abnormal, an annunciation part 18 such as a buzzer gives a cooking person a warning.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a cooking appliance with an infrared sensor that detects the temperature of food to be cooked using an infrared sensor.

[Technical background of the invention]

Generally, this type of cooking device, such as a microwave oven, is equipped with an infrared sensor on the ceiling of the heating chamber, and this infrared sensor catches the infrared rays emitted from the food to be cooked, and the temperature of the food to be cooked is determined by the output of the infrared sensor. Surface temperature)
We are trying to detect this. Then, when the temperature of the target food reaches the set value, the cooking ends. FIG. 1 shows the configuration of such a microwave oven with an infrared sensor. In the figure, 1 is a main body, and this main body 1 is provided with a heating chamber 2. A shelf board 4 is provided within the heating chamber 2 on which the food to be cooked 3 is placed. Furthermore, a high frequency generator such as a magnetron (not shown) is provided on the back side of the heating chamber 2, and this magnetron antenna is connected to the heating chamber 2.
be introduced within. Further, an infrared transmission hole 5 is formed in the ceiling surface of the heating chamber 2, and an infrared sensor unit and a trolley are arranged on the back side of the ceiling surface corresponding to the infrared transmission hole 5. The infrared sensor unit 6 is composed of an infrared sensor (pyro sensor) 6a and a chopper 6b, and as shown in FIG. Temperature detection is performed by intermittent infrared rays irradiated from the infrared sensor 6a to the infrared sensor 6a.

[Problems with background technology]

However, with the above configuration, if substances released from the food to be cooked during cooking adhere to the light-receiving surface of the infrared sensor 6a, the sensitivity of the sensor will decrease, and the cook will be able to use mW without realizing it. If this method continues, the food to be cooked will be constantly heated by the high frequency generator, resulting in cooking failures and accidents.

[Purpose of the invention]

This invention was made in view of the above circumstances,
The purpose is to provide a cooking appliance with an infrared sensor that can detect dirt attached to the infrared sensor and prevent abnormal cooking.

[Summary of the invention]

That is, in this invention, an infrared sensor unit equipped with a plurality of infrared sensors is provided on the back side of the ceiling surface of the heating chamber 2, and the outputs of each of the infrared sensors are compared by a comparison means, and the comparison output is used to determine the output of each infrared sensor. It is configured to detect abnormal output and prevent abnormal cooking.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Figure 3 shows its configuration.
Components that are the same as those in the figures are given the same reference numerals and their explanations will be omitted. That is, an infrared sensor unit 6 including a plurality of (two) infrared sensors /ia1, 6a2 is provided on the back side of the ceiling surface of the heating chamber 2. Incidentally, infrared transmission holes 51, 5, . is formed, and the infrared sensors 6 & 1g6 pass through the infrared transmission holes 51 and 52.
The infrared rays supplied to &2 are interrupted by chopper 6b.

On the other hand, 10 is a power source, and this power source xof is connected to the primary side of a high voltage transformer 13 via a switch (for example, a relay contact) 11 and a trier, RI J2 in series. The magnetron (not shown) is connected to the secondary side of the high voltage transformer 13. Furthermore, the power supply 10 has the switch 11
The drive 1'11 circuit 30 of the chopper 6b is connected via a switch (for example, a relay connection!) J4 in series. Reference numeral 15 denotes a main control unit that stores a microcomputer, and this main control unit 15 controls each infrared sensor 6 a 1 # 6 supplied via a sensor output processing circuit 16 .
The temperature of the food to be cooked is detected based on the average value of each infrared sensor by comparing the outputs of a-, and the switch 11 is turned on or off according to the detected temperature and the cooking program preset on the operation unit 12. It controls the conduction of the trier 12. In addition, infrared sensor 6m1
, 682, based on the output of the sensor output processing circuit 16, a warning is issued to the cook by the notification section J8, which may be a buzzer or the like.

5- In the above configuration, the operation will be explained with reference to the flowchart in FIG. First, when automatic cooking is selected by the operation unit 17 and a cooking start operation is performed, microwave cooking using high frequency is started. At this time, infrared sensor 6
11@6a! Detection of the temperature of the food to be cooked 3 is started. First, the detection data D1 of one infrared sensor 6a1 is stored in a storage device built into (or connected to) the sensor output processing circuit 16, and then the detection data D of the other infrared sensor 6a2 is stored in the storage device. Next, the two stored detection data are compared by the main control unit 15, and when the detection data D1rD1 are almost equal, it is assumed that normal temperature detection has been performed, and cooking is performed using the average value as the temperature data of the food to be cooked. The heating process d1q is performed while repeating the temperature detection operation described above until the cooking program preset by the operation unit 12 is completed. When the cooking program ends, the temperature detection operation is also stopped.

On the other hand, if there is a large difference between the stored detection data D1sDm, it is determined that dirt has adhered to one of the infrared sensors, and the notification unit 18 issues a warning to the cook, and the main controller 15 In response to the output, switch 1 is turned off to stop cooking and terminate the temperature detection operation.

Therefore, it is possible to determine whether dirt has adhered to one side of the infrared sensor, and abnormal cooking can be prevented.

FIG. 5 shows a modified configuration example of the infrared sensor unit and toro in FIG. 3, in which two infrared sensors 681 16 &! A chopper 6b is provided between them, and this chopper 6b is driven by the excitation of a chopper moving inlet 7 to alternately interrupt and intermittent the infrared rays supplied to the infrared sensors 6ml and 6aH.

Even in such a configuration, the same effect as shown in FIG. 3 above can be obtained.

In the above embodiment, the case where there are two infrared sensors has been explained, but three or more infrared sensors may be provided, and in this case, the fifth infrared sensor
As shown in chart 70 of the figure, first, the temperature detection data DB a D mushroom gD3,... are sequentially stored in the storage device, and m data with decreased sensitivity are selected from among the n stored detection data. to sort out. Next, if the output of at least two infrared sensors has not decreased, the cooking program is executed using the average value of the outputs, and if the output of all infrared sensors except for one infrared sensor has decreased, the infrared sensor When it determines that there is dirt on the food, it issues a warning and stops cooking.

When three or more infrared sensors are installed in this way, even if dirt adheres to the sensors, if two or more sensors are normal, the heating temperature of the food to be cooked can be controlled based on the outputs of these sensors. .

Furthermore, in each of the embodiments described above, the same chopper is used to cut off the infrared rays supplied to the plurality of infrared sensors, but it goes without saying that a chopper may be provided for each infrared sensor.

In addition, the infrared sensor is equipped with a repair mechanism, so that when the main controller determines that the infrared sensor is dirty and the light-receiving surface needs cleaning, the repair mechanism increases the amount of dirt that has adhered to the sensor and removes it. This allows for less maintenance.

〔Effect of the invention〕

As explained above, according to the present invention, an excellent cooking appliance with an infrared sensor that can detect dirt attached to the infrared sensor and prevent abnormal cooking can be obtained.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing the configuration of a conventional cooking appliance with an infrared sensor, FIG. 2 is a diagram showing the configuration of the infrared sensor unit in FIG. 1, and FIG. 3 is a diagram according to an embodiment of the present invention. A fourth diagram schematically showing the configuration of a cooking device with an infrared powder sensor.
The figure is a 70-chart explaining the temperature detection operation of the cooking appliance with an infrared sensor shown in FIG. 3 above, and a diagram showing a modified configuration example of the infrared sensor unit in FIG.
FIG. 6 shows 70-70 for explaining another embodiment of the present invention.
It is a chart. 3... Food to be cooked, 6... Infrared sensor unit,
9-6 1p6112...Infrared sensor, 6b...Chopper. Applicant's agent Patent attorney Takehiko Suzue 10- Figure 1 Figure 2 Figure 5 Figure 6 Figure 6 4-1 Isui Tenita D1 i<n YES ・ 1--1◆1 N. n+2 downfall. n−m≧2NO

Claims (1)

[Claims] It comprises a plurality of infrared sensors, a comparison means for comparing the outputs of these infrared sensors, and a means for determining an abnormality in the output of each infrared sensor based on the comparison output from the comparison means, A cooking appliance with an infrared sensor, which detects the temperature of food to be cooked using an infrared sensor with a normal output, and automatically cooks food according to the detected temperature.