JPS5918321A - Heat-cooking utensil - Google Patents

Abstract

PURPOSE:To produce a fan with a consistent quality and to improve an entire heating efficiency, by constituting a hot air circulation type oven such that a circulation fan to be fitted to a heating chamber wall has its blade formed by bending the recessed part of metallic plate substantially to a right-angle. CONSTITUTION:In manufacturing a hot air circultion fan 8, slit recesses are defined over a metallic disc which is then bent along a recessed periphery substantially to a right-angle for thereby forming a blade 8a. By so arranging, the blade 8a can be formed to have a precisely uniform height and a balanced configuration even if a plate material of different thickness is used, and thereby reducing the parts number and the weight. As a result, the fan can increase its r.p.m. and consequently an air velocity and an air volume. Furthermore, by limiting the diameter of punch hole defined in the rear wall of heating chamber, opened areas of blow-out and suction ports can be made as small as possible, and thereby allowing an ample air velocity as necessary for cooking operation. This arrangement can ensure the manufacture of stable quality fan, which leads to the improvement in heat efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a so-called open hot air circulation method in which the temperature inside a heating chamber is increased by an electric heater and a circulation fan, and the heat distribution within the heating chamber is made uniform. It is an object.

Structure of the conventional example and its problems In the conventional high-frequency heating device shown in FIG. A surrounding electric heater is attached, and by rotating a circulation fan 8, the temperature in the heating chamber 1 is maintained uniformly, and cooking can be performed in two stages, an upper stage and a lower stage. In order to make the temperature inside the heating chamber 1 uniform in this way, a large amount of air is required, and the air cannot reach every corner of the heating chamber 1 unless the air speed at the outlet is high. As shown in FIG. 2, the structure was constructed by spot welding a component 8c with two blades 8b on one circular metal plate 8a at four points. This was to increase the height of the blades 8b to increase the air volume and speed.

However, such a configuration requires two types of parts, and due to variations in the plate thickness of the material that makes up the blades 8b, the balance of the fan 8 is easily lost due to slight deviations in spot welding, and the motor vibrates, causing abnormalities. The problem of noise generation often occurred.

In addition, the unbalanced circulation fan 8 requires a large amount of materials and man-hours to construct the circulation fan 8, such as by adding a balancer to maintain balance. Moreover, since a large amount of material is used, the weight becomes heavy, and the motor for rotating the fan 8 must have a large torque.

Purpose of the Invention The present invention solves the above-mentioned drawbacks of the conventional method.The purpose of the present invention is to use a low-cost, well-balanced circulation fan to maintain a uniform temperature in the heating chamber, thereby enabling effective oven cooking. Further, the present invention circulates hot air between the heating chamber and the heater mounting box using a lightweight and efficient circulation fan and an electric heater in the electric heater mounting box provided at the rear of the heating chamber. The purpose of this is to enable two-stage cooking in the heating chamber.

Structure of the Invention In order to achieve the above-mentioned object, the heating device of the present invention comprises a circulation fan with blades formed by cutting grooves in a single circular metal plate and bending the grooved portions. In addition, the number of punched holes in the rear wall of the heating chamber has been reduced to allow hot air to be blown only to the necessary areas, increasing the wind speed and improving the ability to perform effective oven cooking even with a low blade height. be.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

In the figure, 1 is a heating chamber in which food is placed and heated by high-frequency heating or electric heater heating, 2 is a magnetron which is a high-frequency oscillator that supplies high-frequency power to heating chamber 1, and 3 is a magnetron (magnet) on 2.
A waveguide 4 guides and supplies high-frequency power oscillated to the heating chamber 1, and 4 is a top electric heater, which is fixed at the top of the heating chamber 1 and is used for grilling, etc., to create brown marks on the surface of the food. Its role is to attach. As the upper surface electric heater 4, an electric heater such as an infrared heater is used. 6 is an electric heater installation inner box attached to the rear surface of the heating chamber 1, and an electric heater 7 for hot air circulation is attached by an insulator 6. 08 is an inner box for installing an electric heater 7 for hot air circulation. A fan that circulates air. Reference numeral 9 designates an open saucer used when baking bread, kutsky, or other oven cooking using components for circulating hot air such as an electric heater 7 and a fan 8.

In a high-frequency heating device with an electric heater configured as described above, if the hot air circulation fan 8 is configured with a single metal plate, two types of parts are not used as in conventional circulation fans, and the blades can be Eliminates imbalance due to variations in plate thickness and misalignment of spot welds. That is, the second
In the case of the conventional circulation 77n 8 shown in the figure, the parts that constitute the two blades 8b are welded at four points to the circular plate 8a, so a total of five parts are used, and the blades If the thickness of the material used to make 8b changes, fan 8 will be replaced immediately.
The balance will be disrupted. However, the cycle 77 of the present invention
With fan 8, since it is composed of one part, even if the thickness of the material changes, only the weight of each fan will change, and the height and balance of the blades 8a can be accurately determined using the mold. Decided,
The balance of each fan itself is maintained.

In addition, since it is a single part, it can be completed by simply pressing it with a mold, and there is no need for spot welding, reducing both material and assembly costs.

Furthermore, by reducing the number of parts and lowering the height of the blades 8a of the fan 8, the weight of the fan 8 can be reduced, and although the air volume at the same rotation speed is reduced compared to the conventional fan 8, it is lighter. Because the number of revolutions increases due to 1. There is no difference in air volume or speed from the conventional 77-8. In addition, by opening holes in the rear wall of the heating chamber 1 only in the areas necessary for cooking, the opening area of both the air outlet 10 and the suction port 11 is reduced, increasing the wind pressure and ensuring a sufficient wind speed for oven cooking. will be obtained.

Furthermore, some oven cooking menus tend to stain the inside of the heating chamber 1 and the inside of the electric heater mounting box 5 due to oil splashing or smoke generation. Since the opening area of the rear wall of the heating chamber 1 is reduced by use, there is less dirt in the electric heater mounting box 5, which has been difficult to clean in the past.

Another effect is that by combining the circulation fan 8 of the present invention and the approximately M-shaped electric heater 7, it is possible to make the electric heater mounting box 6 shallow and small. Therefore, the circulation volume of hot air is reduced, heating efficiency is increased, and the temperature rise time in the heating chamber 1 is shortened, allowing efficient open cooking.

Effects of the Invention As described above, according to the present invention, by configuring the hot air circulation fan with a single metal plate, a circulation fan with stable quality can be obtained at a low price, and an energy-saving type high-frequency heating with high thermal efficiency can be obtained. The device will be obtained.

[Brief explanation of drawings]

Fig. 1 is a front cross-sectional view of the main parts of a conventional high-frequency heating device with an opening, Fig. 2 is a front view of the same circulation fan, and Fig. 3 is a main part of a high-frequency heating device with an opening showing an embodiment of the present invention. 4 is a side sectional view of the main part, FIG. 6 is a front view of the electric heater attachment part, and FIG. 6 is a front view of the circulation fan. 1... Heating chamber, 2... Magnetron, 3
... Waveguide, 4 ... Top electric heater,
6...Electric heater mounting box, 6...Insulator, 7.
...Electric heater, 8...Circulation fan, 9...
...Open saucer. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] The main body is provided with an oven tray and a heating chamber in which the objects to be heated are stored in upper and lower stages for cooking, and an electric heater mounting box equipped with an electric heater, a circulation fan device, etc. on the side wall or back wall of the heating chamber, and the heating The configuration is such that the air in the room and the electric heater mounting box is circulated, and the circulation fan is made by cutting grooves in a single metal disc, bending the grooved part at a right angle or at an angle close to a square angle, and forming blades. A heating cooking device comprising: