JPS62299631A - Heater - Google Patents

Abstract

PURPOSE:To make it possible to control the temperature of atmosphere in a control section regardless of varying factors outside of the body of a device by providing a temperature sensing element near the control section of the device main body and controlling a cooling fan with a microcomputer, etc. CONSTITUTION:When the inside of an electric oven storage chamber 4 is heated to a high temperature without driving an electronic range 5, a microcomputer 16 keeps open relays 17 and 18 and 19 respectively until a temperature sensing element 23 detects a certain temperature. When the inside of the electric over storage chamber 4 is operated for a long time and the atmosphere temperature of the control section reaches a certain temperature, the microcomputer 16 closes a relay 17 and operates a cooling fan 20 regardless of the opening and closing of a door switch 15. At this time the computer 16 closes the relay 17 regarding of the opening and closing of a door switch 15. A cooling fan 17 is, because of its position in front of a door switch 14, operated regardless of the opening and closing of a door switch 14. With this arrangement in either case of the opening closing of the door switch 14, it is possible to operate the cooling fan 20 only by the temperature of the atmosphere for control parts in either case of opening or closing of the front door of the electronic range 5.

Description

DETAILED DESCRIPTION OF THE INVENTION 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to a heating device such as a microwave oven, which is used in combination with a cooking appliance such as a heater, such as an electric opener.

Conventional technology In general, electric opening requires a normal cooking temperature in which the inside of the refrigerator is cooked at a temperature of, for example, 300°C or less, and a self-cleaning time in which the food gas inside the refrigerator is burned off at a high temperature of, for example, 450°C or more and up to 500°C. There are two temperature modes. In a heating device such as a microwave oven that is used in combination with such an electrical open circuit, the ambient temperature of the microcomputer in the control section in the former temperature mode is at a level that does not pose a problem, and the ambient temperature of the microcomputer in the latter temperature mode is Temperature refers to the allowable operating temperature, and microcomputers that are sensitive to temperature may malfunction. In such a heating device, in order to cool the control section, a temperature switch 1 is provided in the control section as shown in FIG. An effective method is to rotate the cooling fan 3 to maintain a certain temperature below the permissible operating temperature. It exhibits the characteristics shown in the figure. However.

In this type of control, when the ambient temperature of the microcomputer rises to the set temperature of the temperature switch, the cooling fan starts rotating, and when the ambient temperature falls and the temperature switch returns, the cooling fan stops, so the cooling fan rotates. The operation is very harsh and the temperature switch opens and closes many times, which shortens the life of the contacts. For this reason, in order to prevent complicated operation of the temperature switch, the general method for cooling the control unit is to prevent the ambient temperature around the temperature switch from dropping even if the cooling fan turns, as shown in the figure.

The internal temperature is detected by the thermostat 9 installed in the open refrigerator interior 4, and only when the temperature in the open refrigerator interior 4 reaches the self-cleaning temperature, the cooling fan 3 of the microwave oven 5 is turned on and the control unit 6 is turned on. A cooling method was used.

Problems to be Solved by the Invention However, in the conventional control as shown in FIG.
If an expensive thermostat is required and the heating device control and electrical open circuits are separated,
There were problems in that the two circuits were mixed together and long lead wires were required, which hindered assembly work. moreover,
Since the ambient temperature of the control unit 6 of the microwave oven 5 is not directly measured, the operation setting temperature of the thermostat 9 and the control unit 6
It is necessary to experimentally determine the correlation between the ambient temperature of There is also a problem that the installation varies depending on the condition and the like, and it is difficult to keep the ambient temperature of the control section below a certain temperature.

The present invention solves these conventional problems by detecting the ambient temperature using a temperature sensing element installed in the control unit, and using a microcomputer to continuously operate the cooling fan for a certain period of time. The purpose of the present invention is to provide an excellent heating device that can control the ambient temperature of the control section regardless of fluctuation factors outside the aircraft.

Means to solve problems The 7XI thermal device of the present invention is located near the control section within the main body.

A temperature detection element is installed and a microcomputer is used.

This controls the cooling fan and prevents the ambient temperature of the control unit from rising.

Function: The heating device of the present invention has a temperature sensing element in the vicinity of the control parts in the main body, so that the ambient temperature of the control part can be directly detected and detected by a microcomputer.

In order to rotate the cooling fan for a certain period of time, the installation of the main unit is not affected by the condition or room temperature, etc., and the control part can be heated to a certain temperature. This eliminates mixing with air circuits and improves work efficiency during assembly.

Furthermore, by using a microcomputer to control the operating time of the cooling fan, the temperature sensing element is used to control the operating time of the cooling fan. Since the number of times a contact of one part opens and closes without any movement can be reduced, the number of contacts of one part can be secured.

EXAMPLE 1 A heating device according to the present invention will be explained based on the drawings. As shown in FIG.
is installed on top of. The cooling fan 3 cools the microcomputer 2 and the control unit 6, which includes a temperature detection element 12 and the like.

13 is an operation panel for operating the microwave oven 5 and the electric opener 11. FIG. 2 shows a control circuit for the microwave oven 5. When operating the microwave oven 5, close the front door of the microwave oven 5 to turn on the door switch 1.
4.15 close respectively. By operating the operation panel, the microcomputer 16 controls the relays 17 and 1.
8. Close 19, turn on the cooling fan 20, interior light 21. Drive motor 22. is operated, energizes the high-voltage circuit, and generates high-frequency waves.

When the microwave oven 5 is not operated and the electric open refrigerator interior 4 is heated to a high temperature such as for self-cleaning, the microcomputer 16 does not operate until the temperature detection element 23 detects a constant temperature. Relay 17.18.1
Open each number 9. When the electrically open refrigerator interior 4 is operated for a long period of time, the microwave oven 5 is heated by heat transfer, and when the ambient temperature of the control parts reaches a certain set temperature, the microcomputer 16 closes the relay 17 and operates the cooling fan 20. do. At this time, microcomputer 1
6 is relay 1 regardless of whether the door switch 15 is open or closed.
Close 7. Since the cooling fan 17 is located in front of the door switch 14, it is operated regardless of whether the door switch 14 is open or closed. In this way, whether the front door of the microwave oven 5 is opened or closed, the cooling fan 2o can be operated only according to the ambient temperature of the control parts.

Figure 3 shows how to limit the temperature sensing element's input to the microcomputer, and once the element detects the temperature, the cooling fan runs unconditionally for, say, 30 minutes, and after stopping after 30 minutes, the microcomputer ignores the signal from the temperature sensing element for one minute, then the ambient temperature rises and
It is a diagram showing the internal temperature of the electrically open refrigerator and the ambient temperature of the control unit of the microwave oven when the cooling fan continues to be stopped until the element detects it. The set temperature of the temperature detection element is below the allowable temperature of the microcomputer, for example 6.
0°C, and the ambient temperature while the cooling fan is operating is 40°C.
°C to 50 °C. FIG. 4 is a flowchart in this case.

In this way, it is possible to prevent an increase in the ambient temperature of the control section using only the electric circuit of the microwave oven, and it is possible to reliably cool the microwave oven without being affected by external influences.

In addition, since the cooling fan can be controlled by a microcomputer, it is possible to eliminate harsh operating noise and extend the life of the contacts of the components.

Note that it is desirable that the operating temperature of the temperature sensing element be set to a temperature that will prevent the cooling fan from running unnecessarily during normal cooking.

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

(1) Since an expensive thermostat is not required and an inexpensive temperature element is used, the cost of the product can be reduced.

) Since the temperature of the control unit can be directly detected, it can be reliably cooled, preventing abnormal operation of the microcomputer, and providing highly reliable products.

(3) Since the operation of the cooling fan is controlled by a microcomputer, the unpleasant operation of stopping the operation of the cooling fan can be prevented and the life of the contacts of each component can be extended.

4) Since the thermostat does not protrude into the open warehouse, it is easy to clean and there is no deterioration in detection accuracy due to adhesion of food gas.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway perspective view of a heating device according to an embodiment of the present invention, Fig. 2 is a circuit diagram thereof, Fig. 3 is a diagram of its operating characteristics, and Fig. 4 is a flowchart of an embodiment of the present invention. 1 is a partially cutaway perspective view of a conventional heating device. 2... Microcomputer, 3... Cooling fan open, 6... Control diagram % 10... Heater % 12... Temperature detection element . Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Atsushi 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] It is equipped with a heating chamber for heating food, a control section equipped with a microcomputer and a temperature detection element, a cooling fan for cooling this control section, and a heater necessary for cooking. A heating device configured to detect an ambient temperature of the microcomputer with the temperature detection element and operate the cooling fan for a certain period of time to cool the control unit while executing a burn-out purification mode.