JPH0353439Y2 - - Google Patents

Description

[Detailed explanation of the idea]

INDUSTRIAL APPLICATION FIELD The present invention relates to an electric heating appliance, and more particularly to an electric heating appliance that has a heating plate on its upper surface and that places a mug, a tea server, etc. on the heating plate to keep it warm. BACKGROUND TECHNOLOGY Conventionally, this type of electric heating appliance has a heating plate attached to the upper part of a frame having an opening in the center, an electric heater attached to the lower surface of the heating plate, and a bottom body attached to the lower part of the frame. It was covered. Mugs, tea servers, etc. are placed on top of the heating plate exposed through the opening in the frame to keep them warm. Problems that the invention aims to solve By the way, in this type of electric heating appliance, it is desirable to make the overall shape as thin and low as possible. It is not possible to provide sufficient distance between the two. Therefore, when the appliance becomes hot during use, the table surface is heated by the radiant heat from the bottom, resulting in a considerably high temperature. Although heat shielding has been attempted by providing a heat shield plate or the like between the bottom body and the heater, the effect has not been sufficient. The present invention was devised in view of the above circumstances, and it is an object of the present invention to provide a bottom body structure with extremely high heat shielding effect. Means to Solve the Problems The present invention covers an electric heater with a bottom body made of synthetic resin with legs protruding from its lower surface through a space below the electric heater, and a shiny metal plate is attached to the bottom surface of the bottom body. It is characterized in that it is attached and a metal heat shield plate is provided on the top surface of the bottom body. The present invention will be explained below with reference to the drawings. In the drawings, reference numeral 1 denotes an electric heating appliance main body, which has a frame 3 integrally formed around a bottom body 2, and has a substantially dish-like shape with a shallow recess 4 formed therein. The leg 15 is provided protrudingly. Further, a projecting part 5 is formed in a part of the frame body 3, and the back surface of the projecting part 5 is opened to form a cord storage part 6, and the back surface is covered with a bottom cover 7. 8 is a hot plate. The heating plate 8 has a flat top surface, and has an electric heater 9 and a heater holding plate 10 attached to the back side, and is placed on the electric heating device main body 1 to cover the recess 4, and is attached to the main body with screws 12. 1, and the electric heater 9 is brought into close contact with the back surface of the hot plate 8 by a pressing spring 11. A cavity is formed between the heater press plate 10 and the bottom body 2 by the recess 4 of the electric heating appliance main body 1. 13 is a heat shield plate placed on the bottom body 2, and 14 is a metal plate attached to the back surface of the bottom body 2. Although the heat shield plate 13 is not necessarily required, the effect of the present invention is further improved by providing it. In the present invention, the synthetic resin constituting the bottom body 2 has excellent heat resistance, such as phenolic resin,
Materials with low thermal conductivity are used. Further, as the metal plate 14, a metal with high infrared reflectivity, such as aluminum or stainless steel, is used, and the lower surface thereof is made glossy. The heat shielding structure of the present invention is not limited to electric heating appliances for keeping warm as described above, but can also be used in electric cooking appliances such as rice cookers, electric pots, hot plates, and other appliances equipped with electric heaters. It is also possible. Function: According to the present invention, most of the heat generated by the electric heater 9 heats the hot plate 8, but some of it is used as heat radiation and the other part is used as heat of the air in the recess 4. It is transmitted to the bottom body 2 by conduction and convection. Furthermore, the heat is conducted through the bottom body 2 and transferred to the metal plate 14,
Although the heat radiation from the metal plate 14 is extremely small and is slightly transmitted to the table surface only by heat conduction and convection of the air between the metal plate 14 and the table surface, the space between the metal plate 14 and the table surface Since it is open to the outside and air is constantly circulating, there is little heat transfer to the table surface due to heat conduction and convection of the air in this part, and the table surface is not heated excessively. In addition, as described in the experimental example described later,
According to the structure of the present invention, the heat shielding effect that the bottom body 2 and the metal plate 14 have individually is more effective than simply combining them, and it seems that there is some kind of synergistic effect between the two. However, its effect is unknown. Effects of the invention According to the invention, even if an electric heating device is used on a tabletop, the temperature of the table surface will not rise excessively, and it is safe even if the distance between the bottom of the electric heating device and the table surface is small. , the overall shape can be made sufficiently thin. Experimental Example In order to confirm the effectiveness of the present invention, the following experiment was conducted. For use in the experiment, an electric heating device main body 1 having the shape shown in the drawing was prepared, and a heating plate 8 on which an electric heater 9 and a heater presser plate 10 were stacked was attached to assemble the electric heating device. The thickness of the bottom body 2 was 2.5 to 6.5 mm, and the distance between the lower surface of the bottom body 2 and the table surface was 10 mm. The power consumption of the electric heater 9 is 25W, and the distance between the heater presser plate 10 and the bottom body 2 is 8.5 to 12.5.
It was set to mm. Regarding this electric heating appliance main body 1, when the heat shield plate 13 and the metal plate 14 are not used. When an aluminum heat shield plate 13 with a thickness of 0.2 mm and an area of approximately 57 cm ² is provided at a position 8.5 mm below the bottom surface of the heater holding plate 10. When an aluminum plate 14 with a thickness of 0.3 mm and an area of approximately 35 cm ² is attached to the bottom surface of the bottom plate 2. When both the heat shield plate 13 and the aluminum plate 14 are used. Experiments were conducted for each case. Next, on the bottom body 2 of the electric heating device main body 1, an area of about 25
An experiment was also conducted in which a through hole of cm ² was drilled and placed in the same conditions as in ~ above. In the experiment, an electric heating device was placed on a wooden tabletop, electricity was applied to the electric heater 9, and the temperature of the table surface directly below the center of the electric heating device was measured when the temperature reached equilibrium. In both cases, the temperature of the hot plate 8 is 140
It was warm at ℃. The results of the experiment were as follows.

[Table] As can be seen from the results of this experiment, neither the synthetic resin bottom plate 2 nor the metal plate 14 have a great effect when used alone. In the experiment, when the metal plate 14 was used alone, it seemed to have some effect compared to the experiment;
It should be seen as an effect of shielding the air within the recess 4 rather than a heat shielding effect of the recess 4.
This can be understood from the fact that in experiments, the through holes in the bottom body 2 were not closed by the heat shield plate 13, so there was almost no effect. On the other hand, in the case where the bottom body 2 and the metal plate 14 are used in combination according to the present invention, the temperature of the table surface is significantly lowered, and a temperature of less than 70° C. was achieved for the first time in experiments. If the function of the metal plate 14 in the present invention is simply to reflect infrared rays,
There is no difference whether this is installed on the top or bottom of the bottom body 2.
Results should be approximately the same as in experiments. However, when comparing the results of the experiment and the results of the experiment, the experiment shows a heat shielding effect more than twice that of the experiment, and by using the synthetic resin bottom body 2 and the metal plate 14 together, It is understood that there is a synergistic effect. Although the heat shield plate 13 does not have any synergistic effect when used in combination with the present invention, it alone has a considerable heat shielding effect, and when used in combination with the present invention, the effect diminishes. Therefore, it is preferable to use it together with the present invention.

[Brief explanation of the drawing]

FIG. 1 is a central vertical sectional view of an electric heating appliance to which the present invention is applied. FIG. 2 is an exploded perspective view of the electric heating appliance main body to which a heat shield plate and a metal plate are attached. 2... Bottom body, 9... Electric heater, 14... Metal plate.

Claims (1)

[Scope of utility model registration request] The bottom of the electric heater 9 is covered with a synthetic resin bottom body 2 with legs 15 protruding from the bottom surface through a space, and a shiny metal plate 14 is pasted on the bottom surface of the bottom body 2. A heat shield structure for an electric heating appliance, characterized in that a metal heat shield plate 13 is provided on the upper surface.