JPS58145829A - High frequency heater - Google Patents

Abstract

PURPOSE:To make it possible to detect humidity accurately at all times by a method wherein a self-cleaning device by heating is provided in a humidity sensor and an exhaust air passage near the humidity sensor is made changeable so that it is possible to keep up the original characteristic of the humidity sensor for a prolonged period of time. CONSTITUTION:The high frequency heater is provided with a heating chamber 6 having an air inlet port 7 and an air exhaust port 8, a fan 4 for sucking and discharging air, the humidity sensor 9 provided adjacent the air exhaust port and the self-cleaning device 9b by heating. Further, the exhaust air passage near the humidity sensor 9 is made changeable by the provision of a solenoid 10 and a shutter 11 movable in response to the signal from a control section 3 so that exhaust air is passed through the humidity sensor where it is necessary to detect humidity. As a result, it is possible to keep up the original characteristic of the humidity sensor for a prolonged period of time and to detect humidity accurately at all times to thereby contribute to the automatization of the high frequency heater.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency heating device that is equipped with a humidity detector that detects water vapor and the like from food and that automates cooking.

With the introduction of microcomputers, the operating method for high-frequency heating equipment has become digital, making it multifunctional, but at the same time, it has become less easy to operate, requiring complicated steps to operate it. . Therefore, efforts are being made to automate cooking by using various sensors and combining them with the functions of microcomputers. Among these methods, methods that detect steam or gas from food do not come into contact with the food, so they do not damage the food and save time and effort, so it can be said to be extremely effective. However, in order to detect vapors and gases from food, the detector must be exposed to the atmosphere, making contamination a major issue. Contamination of the detector can lead to cooking failure, overheating and carbonization of the food, and even a fire.

In addition, as methods for detecting humidity and gas, there are methods that control a high-frequency oscillator by detecting the point at which humidity or gas starts to appear, the point at which it suddenly changes, or the point of saturation, and the method that measures the amount of change in humidity or gas. There are methods to utilize the time it takes to reach that amount of change. The former is a rough detection method, and the types of cooking that can be automated and the range of environments are limited, but slight contamination of the detector is not a problem. The latter allows detailed automation of tasks such as defrosting frozen foods, cooking eggs, or adjusting the finish of meat, but on the other hand, even the slightest dirt on the detector can affect the cooking results, so it is important to keep the detector characteristics stable at all times. There is a need to keep it.

The present invention is particularly aimed at preventing contamination of humidity detectors in high-frequency heating devices that require highly accurate control performance, such as the latter.

@1 Figure is an external view of a high-frequency heating device showing an embodiment of the present invention, in which 1 is a control unit including a microcomputer, 2 is a control unit including a microcomputer;
indicates the door, and 3 indicates the exhaust port. FIG. 2 is a partial cross-sectional view before this countermeasure is taken. The magnetron 5 is cooled by the cooling fan 4, and the air enters the heating chamber 6 through the intake lower provided on the wall of the heating chamber 6, and the food (not shown) It is exhausted along with steam and gas from the heating chamber 6 through an exhaust port 8 provided on the wall of the heating chamber 6
Passing through the humidity detector 9, the exhaust port 3 provided in the body
more excreted. 10 is designed to adjust the wind speed or air volume applied to the humidity detector 9.
829 (2) It is an air guide with a slit f'. Due to this configuration, the humidity detector 9 is constantly exposed to food vapor not only in automatic cooking but also in manual cooking, resulting in significant contamination.

Figure 3 shows a humidity detector 9 with a self-cleaning function.
It is a perspective view of the humidity detecting element 9-IL, which is composed of a humidity detecting element 9-IL and a cleaning heater 9-b. In order to increase the cleaning effect, it is necessary to raise the cleaning temperature to a high temperature, and if this operation is repeated, the characteristics may change due to deterioration of the humidity detection element 9-IL, or the cleaning heater may This may lead to failures such as deterioration or disconnection.
There is a way to eliminate cleaning operations as much as possible and avoid doing them unless necessary. However, the humidity detection element 9
- If the & is left contaminated for several days to several tens of days, its properties will not return to normal even if the cleaning temperature is increased.
It will no longer recover.

Therefore, in the present invention, cleaning is performed only at the start of automatic cooking that requires humidity detection, and after humidity detection, the exhaust passage to the humidity detector 9 is closed to isolate it from dirty exhaust gas. . Among the steam, gas, and filth from food, the filth that has a particularly large effect on contaminating the humidity detection element 9-a increases rapidly after the food is boiled. The humidity detection element 9-a detects steam before the food boils, and isolating it from the exhaust air at the same time as steam detection is very effective in preventing contamination. FIG. 4 shows an embodiment in which a shutter 11 is provided on the humidity detector 9 and is opened and closed by a solenoid 1o, and this solenoid is also controlled by signals from the control section 3 described above.

This shutter has a normally closed structure and covers the humidity detector 9 even after the cooking is finished, further enhancing its effectiveness. In addition, it goes without saying that the humidity detector 9 should be covered during cooking other than automatic cooking, but especially with combined cooking appliances that have a microwave oven function and an oven function, unlike when cooking in a microwave oven, the humidity detector 9 must be covered. Since it is accompanied by smoke as a gas, and it cools down after frequent continuous use for long periods of time, contamination from this is extremely severe, and it is extremely difficult to mechanically isolate the humidity sensor without relying solely on the 6-benzo cleaning operation. This is an important point.

As described above, according to the present invention, the original characteristics of the humidity detector 9 can be maintained for a long period of time, and accurate humidity detection can be performed at all times, so that the present invention is greatly useful for automation of high-frequency heating equipment.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is an external perspective view of a high-frequency heating device showing one embodiment of the present invention, Fig. 2 is a partially cutaway view of the same plan view before taking measures, and Fig. 3 is a partially cutaway view of the same plan view before taking measures.
The figure is a perspective view of a humidity detector having a self-cleaning function, and FIG. 4 is a perspective view showing an embodiment in which ventilation of the humidity detector is opened and closed by a shutter. ...Humidity detector, 9-a...Humidity detection element, 9-b...
・Cleaning heater, 1o...Solenoid, 11・River...Shutter 0

Claims (1)

[Claims] (1) A heating chamber, an intake port and an exhaust port provided in the heating chamber, a fan motor for intake and exhaust, a humidity detector provided near the exhaust port, and a humidity detector provided in the humidity detector. a self-cleaning device by heating the humidity sensor, and the high-frequency heating device has a configuration in which an exhaust route near the humidity detector can be changed. (Translation) The above humidity detector is used only when humidity detection is necessary.
The high-frequency heating device according to claim 1, which is configured to allow exhaust gas to pass through.