JPH036422B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a cooling structure for an operation panel and its vicinity in a cooking device such as an electric oven, a gas oven, or a microwave oven with a heater.

Structure of conventional example and its problems A conventional heating cooker 1, for example, as shown in FIG. Electricity is supplied to the provided electric heater 4 to perform heating. At this time, the inside of the heating chamber 2 reaches a high temperature of around 250 degrees Celsius, and the hot air radiated from the heating chamber 2 is absorbed by power supplies such as the high voltage transformer 5 and high voltage capacitor 6, as well as the operation panel 7 and electronic components installed above the door 3. The parts storage space 9 is filled with printed circuit boards 8 etc. equipped with a large number of
The components are exposed to extremely high temperatures. Therefore, cooling is performed by using a cooling fan motor 10 to ventilate air between an intake opening 11 and an exhaust opening 12 provided in a part of the outer shell of the container to the outside of the container. Also at this time, heating chamber 2
The hot air inside leaks from the door 3, and the temperature of the entire operation panel 7 rises, causing the printed circuit board 8 and operation buttons 1 to rise.
3 etc. also reach a high temperature, so an exhaust hole 14 is provided at a position facing the door 3 of the operation panel 7 to cool the above-mentioned parts. However, at this time, as shown in FIG. 2, part of the cooling air generated by the cooling fan motor 10 flows into the heating chamber 2 through the gap l between the contact surface of the door 3 that forms one wall of the heating chamber 2. It was found that the heat flowed into the heating chamber 2 and had an adverse effect on the temperature control and temperature (heat) distribution within the heating chamber 2. In other words, since cold air flows in from the upper part of the door 3, it is difficult to establish a correlation between the detection position of the heating chamber temperature control and the temperature inside the heating chamber 2, resulting in an unstable state. The set temperature varies. or,
As for the temperature distribution, since the vicinity of the door 3 of the heating chamber 2 is naturally cooled, only the object to be heated in the vicinity of the door 3 is not heated easily, resulting in variations in the finished product. Furthermore, when the rotation of the cooling fan motor 10 stops after heating is completed, the hot air in the heating chamber 2 and the water vapor generated from the object to be heated are discharged from the gap l as shown in FIG. 14, flows into the parts storage space 9,
The air is exhausted to the outside of the vessel through an exhaust opening 12 provided in a part of the outer shell of the vessel. In other words, when the cooling fan motor 10 during heating is rotating, the high voltage transformer 5 and the high voltage capacitor 6 in the parts storage space 9 are
The microcomputer 15, transistor 16, capacitor 18, pushbutton switch 19, and other electronic components on the printed circuit board 8 provided on the operation panel 7, as well as the operation button 13 on the operation panel 7, are sufficiently cooled; When the cooling fan motor 10 stops, all of the above-mentioned parts are exposed to the residual heat and water vapor in the heating chamber 2, which not only deteriorates the durability and reliability of the parts due to high temperatures, but also
Water vapor condenses on the printed circuit board 8, causing the circuit to become short-circuited, leading to significant deterioration of insulation resistance and runaway and malfunction of the microcomputer 15, resulting in an extremely dangerous situation. In addition, since the operation panel is usually made of resin molded product, extremely expensive heat-resistant materials must be used to avoid thermal deformation due to high temperatures. This would have led to a situation of

OBJECT OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks and does not affect temperature control or temperature distribution. The purpose is to create a structure that will not cause dangerous conditions such as deterioration of insulation resistance and malfunction of the microcomputer due to exposure to

Structure of the Invention In order to achieve the above object, the heating cooker of the present invention has the following features:
The container body is divided into upper and lower parts by a partition member, the lower part is a heating chamber, and the upper part is a parts storage space, a door is provided in front of the heating chamber, and a heating means is provided in the heating chamber, and a rear part of the parts storage space is provided. An intake opening is provided at the front, an exhaust opening is provided at the front, and a cooling fan motor installed in the parts storage space allows air to flow mainly from the intake opening to the exhaust opening. An operation panel section with a printed circuit board is provided on the front side of the storage space, and a metal plate is disposed between the operation panel section and the door so as to partition them, and one end is connected to the partition member, and the metal plate It has an opening at the front, and when the temperature inside the heating chamber is high, the cooling fan motor protects the internal and external electronic components, electrical components, operation panels, operation buttons, etc. both during and after heating. This configuration allows the cooling air from the cooling fan motor to flow back into the heating chamber while keeping the temperature rise of the parts low, without adversely affecting temperature control or temperature (heat) distribution within the heating chamber. In addition, when heating is finished and the fan motor is stopped, it prevents hot air in the heating chamber and water vapor generated from the heated object from flowing back into the parts storage space, especially for electronic devices such as microcomputers, transistors, display tubes, etc. In addition to keeping the temperature rise to parts low, water vapor condenses between patterns on printed circuit boards and in areas with small insulation distances such as microcomputers, resulting in short circuits, resulting in malfunctions, runaway microcomputers, and dangers such as electric shocks due to deterioration of insulation resistance. Since it is possible to easily keep the temperature rise of the operation panel, operation buttons, etc. low, there is no danger of the user touching it and getting burnt.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings.

In FIG. 4, by attaching a metal plate 20 to the surface of the operation panel 7 facing the door 3, a fifth
As shown in the figure, a first opening 21 and a second opening 21 form a ventilation passage 23 and a part of the cooling air from the cooling fan motor 10 is formed by the operation panel 7 and the metal plate 20.
The air is exhausted to the outside of the vessel through the opening 22. Further, a door 3 is arranged below the operation panel 7. At this time, since the door 3 constitutes one wall surface of the heating chamber 2 and can be opened and closed, a gap of l is created to some extent on the contact surface. On the other hand, a microcomputer 15 and a transistor 1 are located inside the operation panel 7.
6, a printed circuit board 8 on which electronic components such as a display tube 17, a capacitor 18, a pushbutton switch 19, and the like are mounted. Also, inside the heating chamber 2 or heating chamber 2
A temperature switch 24 is provided to detect a temperature rise in the vicinity.

The operation of the above configuration will be explained below.
When an object to be heated is placed in the heating chamber 2 and the temperature is raised by the electric heater 4, the cooling fan motor 10 starts rotating as soon as the electricity is turned on or when a temperature rise is detected by the temperature switch 24. After the outside air is sucked in through the intake opening 11 to cool electrical components such as the high-voltage transformer 5 and the high-voltage capacitor 6 in the component storage space 9, the air is drawn out of the container through the exhaust opening 12 provided in the outer shell of the container. be discharged. On the other hand, a part of the cooling air is sent to the microcomputer 1 installed near the operation panel 7 installed on the front of the device.
5. A first opening 21, a ventilation passage 23, and a second opening that cool the transistor 16, display tube 17, capacitor 18, etc. and are constituted by the lower surface of the operation panel 7 facing the door 3 and the metal plate 20. 22 and is discharged outside the vessel. Further, the temperature rise of the operation panel 7 and the operation buttons 13 can be kept low because the hot air from the gap 1 of the door 3 is forcibly exhausted. Furthermore, since the directionality of the cooling air is determined by the ventilation passage 23, the cooling air is reliably discharged to the outside of the container. Next, the heating is completed and the cooling fan motor 10
When the heating chamber 2 stops, the temperature of the parts storage space 9 gradually rises due to the residual heat in the heating chamber 2, but even with the gap l between the door 3, the ventilation path formed by the operation panel 7 and the metal plate 20 becomes a maze. Furthermore, since the pressure inside the component storage space 9 due to the temperature rise is slightly higher than that of the outside air, most of the hot air and water vapor generated by the object to be heated are discharged to the outside of the container. or,
When detecting a temperature rise in or near the heating chamber 2 and driving the cooling fan motor 10 to perform a delayed operation, depending on the purpose, the cooling fan motor 10 may be driven after the temperature rise in the heating chamber 2 becomes high. However, after the heating is completed and the residual heat in the heating chamber 2 is removed, the driving of the cooling fan motor 10 is stopped.

As described above, according to this embodiment, when the object to be heated is being heated or the temperature in the heating chamber 2 is high, the cooling fan motor 10 efficiently controls electronic parts, electrical parts, other structural parts, operating parts, etc. Cool well;
Cooling air flows back into the heating chamber 2 through the gap l of the door 3, and does not adversely affect temperature control or temperature (heat) distribution within the heating chamber 2. Moreover,
Even when heating is completed and the cooling fan motor 10 is stopped, residual heat in the heating chamber 2 and water vapor generated from the object to be heated will not flow back into the parts storage space 9 through the exhaust hole 14 provided on the bottom surface of the operating unit. In particular, a printed circuit board 8 and a microcomputer 1 provided inside the device body in close proximity to the operation panel 7
5. Charging that suppresses the temperature rise of electronic components such as the transistor 16, display tube 17, capacitor 18, etc., and has a very small pattern on the printed circuit board 8 due to condensation of water vapor or the insulation distance of the microcomputer 15, display tube 17, etc. Risk of electric shock and malfunction due to deterioration of insulation resistance due to short circuit phenomenon,
Dangerous situations such as runaway caused by the microcomputer 15 can be easily avoided. At this time, the temperature switch 24 detects a temperature rise in or near the heating chamber 2, and the fan motor 10
The above effect can be significantly improved by appropriately setting the temperature when driving and stopping the fan motor 10, and it is possible to reduce the temperature rise in the heating chamber 2 and other locations to be cooled. The fan motor 10 is not rotated when the temperature inside the heating chamber 2 is suddenly increased.
Alternatively, an energy-saving design such as not rotating even when the heating set temperature is low is also possible. In addition, it is naturally possible to keep the temperature rise inside the container and the outer shell of the container, as well as the temperature rise of the operation panel 7, operation buttons 13, etc., to an extremely low level. Electrical parts, electronic parts, and other resin structural parts can be made from cheaper materials with lower heat resistance, which prevents users from feeling uneasy when touching hot parts, and from risking burns. Things are easy.

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

(1) When the object to be heated is being heated or the temperature inside the heating chamber 2 is high, the cooling fan motor will cool the electrical components, electronic components, other structural parts, operation panels, operation buttons, outer shell of the container, etc. inside the container. Cooling air flows back into the heating chamber from gaps in the door, etc., and does not adversely affect temperature control or temperature (heat) distribution within the heating chamber.

(2) Even when heating is finished and the fan motor is stopped, the residual heat and steam in the heating chamber do not flow back into the container, making it possible to keep the operating temperature of electronic components low, especially. In particular, the electronic circuit has a safe structure without the risk of malfunction due to short circuit phenomenon caused by water vapor condensation, runaway of the microcomputer, or risk of electric shock due to a drop in insulation resistance.

(3) Due to efficient cooling in a limited space, the storage space for electrical components etc. can be reduced, making it easy to make the device smaller, lighter, and space-saving in design. By using an inexpensive material with low heat resistance as the insulating material for electronic components, a significant cost reduction can be achieved.

(4) It is possible to prevent the user from feeling anxious due to the high temperature and risk of burns when touching the device, operation panel, operation buttons, etc.

(5) When a temperature rise is detected and the cooling fan motor is driven to perform a delayed operation, the above-mentioned effects are significantly improved and an energy-saving design is easily possible.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the cooling structure of a conventional high-frequency heating device with a heating device, Figure 2 is an enlarged sectional view of the main part of Figure 1, and the arrows indicate the flow of cooling air by the fan motor. In the enlarged sectional view of the main part of Fig. 1, the arrows indicate the flow of hot air and steam when the fan motor is stopped, and Fig. 4A shows the main part of the operation panel of the heating cooker, which is an embodiment of the present invention. Perspective view,
Fig. 4B is a perspective view of the same metal plate, Fig. 5 is an enlarged sectional view of the main part of the same embodiment, and arrows indicate the flow of cooling air by the fan motor. Fig. 6 is an enlarged cross-section of the main part of the same embodiment. In the figure, the arrows indicate the flow of hot air and steam when the fan motor is stopped. 2...Heating chamber, 3...Door, 4...Electric heater (heating means), 7...Operation panel, 20...Metal plate, 10...Fan motor, 11...Intake opening, 12... Exhaust opening, 21...first opening, 22...second opening, 23...ventilation path, 24...temperature switch (means for detecting temperature rise).

Claims (1)

[Claims] 1 The container body is divided into upper and lower parts by a partition member, the lower part is a heating chamber, and the upper part is a parts storage space, a door is provided in front of the heating chamber, and a heating means is provided in the heating chamber, and the parts storage space is provided. An intake opening is provided at the rear, an exhaust opening is provided at the front, and a cooling fan motor installed in the parts storage space causes air to flow mainly from the intake opening to the exhaust opening, and further An operation panel section with a printed circuit board is provided in the front section of the parts storage space, and a metal plate is arranged between the operation panel section and the door so as to partition them, and one end is connected to the partition section, and a metal plate is arranged between the operation panel section and the door so as to partition them. A heating cooker with an opening in the front part of the plate.