JPS59200131A - Heater with sensor - Google Patents

Abstract

PURPOSE:To improve the reliability of a heater with a sensor by monitoring a sensor signal fed from a contactor of the sensor in a controller based on a timing manner, and ignoring the signal even if an error signal is accepted. CONSTITUTION:A voltage determined by the resistance of a sensor is inputted to an analog input unit 15, and digitized by an A/D converter 16. Digital information on the converter 16 is stored in a new data area 17 by a clock unit 24 for controlling a time at the every prescribed time. Then, the variation is calculated by a comparator 19 which compares the information on the area 17 with information on an old data area 18, checked by a data effect discriminator 20 which judges whether it is valid or invalid. If it is invalid, the information on the area 17 is eliminated, but not shifted to the area 18, and the information on the area 18 is stored as before. Further, a defect detection counter is incremented. When the invalid data is continued, a defect detection counter 21 is overflowed, a microcomputer judges it as a defect, it is inputted to a defect operation processor 23 to reset all relays, thereby stopping the energization of a magnetron.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control device for a microwave oven equipped with a sensor for detecting the temperature, humidity, etc. of food to be cooked and inside the oven.

Structure of conventional example and its problems For example, in the conventional electronic lens with a temperature sensor probe, the temperature sensor probe beam is inserted into the receptacle 8, and the sensor probe T is inserted at the tip of the main body of the receptacle 8.
A signal is sent to the control unit 9 from the insulated terminal portions of the thermistor inside the thermistor so that they are directly connected to the contactor 10 in contact. However, there are problems with the number of contacts 10, contact pressure, dirt on the contact parts,
In addition, when the contact part rotates or moves, an erroneous VC signal is temporarily input to the control unit 9, causing the control unit 9 to malfunction and resulting in poor cooking quality. ing. Conventionally, the control section 9 read the signal from the thermistor twice in succession, and only when the signals coincided with each other, the signal was treated as a normal signal. [-However, this configuration is not effective against false signals that last a long time, such as the bouncing mentioned above, and if the number of readings is increased, the signals will not match continuously, so the control unit (d normal This causes the inconvenience that the cooking progress is slow because the signals are not handled properly.

Purpose of the Invention Therefore, the present invention 1d solves the above-mentioned conventional drawbacks.
The sensor signal sent from the contact part of the sensor is monitored over time by a control unit, such as a microcomputer (hereinafter referred to as microcomputer), and even if an erroneous signal is received, the signal is ignored to ensure highly reliable cooking. The purpose of the present invention is to provide an electron beam/electronic lens that performs the following steps.

Structure of the Invention In order to achieve the above object, the sensor additional heat device of the present invention inputs the &C sensor signals at certain time intervals to a microcomputer (d) which is a control unit, and further stores previously taken sensor signals and uses the information. The microcontroller checks the amount of change in the input sensor signal by comparing the values, and ignores false information if the change exceeds a predetermined value for a predetermined period of time. Since it handles only signals and controls cooking using that information, it has the advantage of preventing erroneous cooking and enabling efficient and reliable cooking.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an external view of one embodiment. Reference numeral 1 denotes a main body of an I-toxin 7, and a heating chamber 2 is provided within this main body. Heating chamber 2 ((A turntable 3 is installed to make the radio wave distribution more uniform 3w. Also, a door 4 that can be opened and closed at the front of the heating chamber 2 is added) 9 In addition, the operation panel 5 provided on the front of the main unit 1 has a keyboard 6 for setting cooking time, output, finished temperature, etc. , a display tube 12 for displaying various information, etc. are provided.

Further, a temperature sensor probe 7 and a septacle 8 are provided in the upper part of the heating chamber 2 to directly sense the temperature of the finished food.

FIG. 2 is a professional diagram of this configuration. 10 is a contact portion that comes into contact with the temperature sensor probe 7 inserted into the receptacle 8. Temperature sensor probe for cooking food 1
3, the resistance value changes depending on the temperature, and in terms of the circuit, the resistance at both ends of the contact portion 10 changes as the resistance value between A and B changes.

As a result, the voltage at point B is determined by the division ratio of the fixed resistance Re and the sensor resistance, and the microcomputer 9 (I'i) converts the temperature of the food 13 by that voltage. Based on this information, the microcomputer 9 Controls the control unit 11 and controls the magnetron 14
The food 13 to be cooked is heated by controlling the energization to.

Reference numeral 6 is a membrane key manual section for setting cooking time, cooking output, and finished temperature, and 12 is a display tube for displaying the information.8 Next, Fig. 3 shows a control method according to the present invention as a block diagram of the operation of a microcomputer. explain.

First, the voltage determined by the resistance of the sensor (hereinafter referred to as sensor information) enters the analog input section 15, and is converted into a digital signal by the A/D conversion section 16.

A clock unit 24 that controls the exact time stores the digital information of the person/D conversion unit 16 in the new data area 17 at certain time intervals. Next, a comparing section 19 that compares the information in the new data area 17 and the information in the old data area 18 calculates the amount of change, and a data validity determining section 20 checks the amount of change and determines whether the data is valid or invalid. If it is valid, the information in the new data area 17 is transferred to the old data area 18, and the normal operation processing section 22 is executed to perform normal cooking. The failure detection counter 21 is cleared at the same time.

- If it is determined that the data is actually invalid, the information in the new data area 17 is discarded and the information in the old data area 18 is not transferred to the old data area 18, and the information in the old data area 18 is stored in the same size as before. Furthermore, the failure detection counter is incremented. If invalid takes continue, the failure detection counter 21 determines that there is an overflow and a failure of the microcomputer 9fri, and the failure operation processing unit 23 enters and resets all the relays to stop energizing the magnetron 14 and indicate a failure in the display tube 12. "--Display (e.g. 'FFFF').

Hereinafter, the effects of the above configuration will be explained.

FIG. 4 shows an example of the operation.

ΔDx is a level width indicating the effective range of changes in sensor data, and if the level difference between the information in the new data area 17 and the information in the old data area 18 compared by the comparison unit 19 is greater than or equal to this effective range Δ])x It is treated as invalid data, and if it is within the range, it is treated as valid data. In Figure 8, Dl →D
2 + D2 > D3. D3→]) is within the valid range at t, but D5 becomes invalid data because the level of D4 deviates from the level of D4 beyond the valid range. But D
Since the data of D6 is within the effective range from the level of D4, D6 is treated as valid data and cooking continues as normal. The same goes for D7; D7 becomes invalid data, but returns to normal at D8, so normal operation continues. In figure b, D1→D2°D2→D3. D, →D4
Up to D5, normal operation is performed with changes within the effective range.
A change beyond the effective range occurs at D6 + D7, DB
+D(1' Dlo and the current level have deviated beyond the effective range, so the failure detection counter that starts counting from the time when D is taken in overflows after T time and detects a failure.8) Next, When the microcomputer 9 detects a failure by importing data as shown in the whistle 4 diagram, it sends a signal to the microcomputer 9id relay control unit 11Vc to turn off the relay and stop energizing the magnetron 14 to stop oscillation. A display notifying the failure is output on the display tube 12. FIG. 5 is an example of this.

In this way, according to this embodiment, since the configuration is such that the validity is determined by comparing the location information from the sensor with the previous information and checking the change, it is possible to ignore incorrect information due to factors such as noise. , it has the effect of eliminating inconveniences in cooking due to the incorrect information.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) Among sensor information, the microcomputer can reliably distinguish between false information due to noise and other factors and true information, eliminating malfunctions of the microcomputer and improving the quality of cooking.

(2) Since the microcomputer makes decisions about incorrect information using software, the structure of the sensor contactor can be simplified.

(3) Since the effective range level width for determining false information can be freely changed using software, it is possible to easily adapt to the fragility of the sensor used.

(4) You can freely determine the time until failure detection by simply changing the value of the failure detection counter. (5) You can freely determine the timing of capturing sensor information depending on the sensor's purpose by simply changing the time of the clock section. .

(6) In the case of a true failure, a message indicating the failure will be displayed on the display and the power to the Madai Tron will be shut off to ensure safety.

(7) The configuration of the present invention can be easily implemented using microcomputer software, which reduces costs.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a microwave oven showing an embodiment of the present invention;
Figure 2 is a control block diagram of the same, Figure 3 is a processing block diagram of the microcomputer, Figure 4 is a front view showing an example of the display when a sensor fails in the electronic system, and Figures 5 a and b.
(d This is a diagram showing the sensor data level of the same microwave oven. 7. Temperature sensor, 9. Microcomputer, 12. Display display, 14. Magnetron Oj.
O heat source). Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 5 1

Claims (2)

[Claims] (1) A heating chamber that accommodates the object to be heated, a heating source coupled to this heating chamber, a sensor that detects the state of the object to be heated, an input section for inputting heating type and heating time, and displaying it. a display section, a means for controlling a heating source, a means for periodically capturing information from the sensor, a means for storing the information, a means for comparing the information, and a means for managing the cycle for capturing information from the sensor. A control unit for controlling the
The sensor additional heat device is configured to ignore information stored in the sensor information storage means and information taken in when the sensor information is processed by the control unit. (2) The sensor heating device according to claim 1, which determines that an abnormal state is occurring and controls the heating source when the sensor information changes more than a predetermined value continuously for a predetermined period of time.