JP3152743B2 - Heating device for electric rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric rice cooker having a heat retaining function.

[0002]

2. Description of the Related Art Generally, an electric rice cooker has means for keeping cooked rice rice warm. FIG. 8 shows an electric rice cooker provided with the heat retaining means. As shown in the figure, a protective frame 2 is provided in a main body 1, a heater 3 is provided in the protective frame 2, and a pot 4 is stored thereon. As a heat retaining means, a heat retaining heater 5 is provided on the outer surface of the protective frame 2,
A thermal reed switch 6 for controlling the energization of the heat retaining heater 5 is mounted on a switch mounting base 7 so as to be located near the protective heater 5. A heat insulating material 40 is provided between the protection frame 2 and the thermal reed switch 6.

In the figure, reference numeral 8 denotes a center thermometer provided at the center of the heater 3 for detecting the temperature at the bottom of the pan 4;
Is locked to the center thermo 8 at the tip and the operation button 10 at the other end
A rice cooker lever, 11 is a frame, 12 is a changeover switch for switching a rice cooking circuit via a rice cooker lever 9 provided on the frame 11 and interlocking with turning on and off of a center thermostat 8, and 13 is a temperature fuse for preventing overheating. , 14 are cooked rice indicating lights.

[0004]

In the above arrangement, the positional relationship between the thermal reed switch 6 and the heater 5 affects the temperature at which the rice is kept warm. Large variation in direction,
There was a problem that the heat retention temperature varied.

The present invention has been made in view of the above-mentioned conventional problems, and a first object of the present invention is to absorb a variation in mounting of a heat retaining heater to a protection frame even when the mounting is vertically varied.

It is a second object of the present invention to provide a structure in which the temperature of the heater is stabilized even when the heater is attached to the protection frame in a vertical direction. A third object is to obtain an electric rice cooker in which the thermal reed switch is hardly affected by the temperature of the outside air even when the heat insulating material is removed, and the heat retaining temperature is stable.

A fourth object of the present invention is to provide an electric rice cooker in which the heat retention temperature is stable even if the heat retention heater floats due to defective bonding.

[0008]

In order to achieve the first object, the present invention relates to a heat-insulating heater provided on the outer periphery of a protective frame for accommodating a pot.
Heater for an electric rice cooker provided with a heater,
One end attached to the bottom of the protective frame and the other end
Install a frame on the side of the protective frame
In contact with the side of the protective frame where the heat retention heater is provided
And at the same time the protective frame is
The width in the vertical direction is more than 1 times the diameter of the heater,
Provide a heat transfer plate with grooves less than double
The end positions the heat transfer plate on the outer periphery of the protection frame.
While keeping it close to the heater.
Set a thermal reed switch to control the energization of the heater.
The thermal reed switch in the form of a plate.
Insert thermal between the heat transfer plate and the other end of the frame
The heat-sensitive part of the reed switch and the heat transfer plate are thermally coupled.
It was made .

According to a second aspect of the present invention, the center of the heater and the center of the thermal reed switch are arranged on substantially the same plane when the heater is closest to the upper end of the protective frame. This is the configuration that is performed.

According to a third aspect of the present invention, there is provided a method for shielding a thermal reed switch and the heat transfer plate from heat.
It is covered with a board . In order to achieve the fourth object of the present invention, the frame is formed in an L-shape, and the opening angle of the two pieces is set to 86 ° to 90 °.

[0011]

In the above configuration, the width of the heat receiving portion of the heat transfer plate in the vertical direction is set to be 1 to 4 times the diameter of the heat retaining heater.
Even when the heater is attached to the protection frame, the variation is large even in the vertical direction, the variation is absorbed.

That is, when the heat retaining heater is closest to the upper side of the protection frame of the heat receiving portion, the center of the heat retaining heater and the center of the thermal reed switch are arranged on substantially the same plane. The distance of the switch is shortened, and the amount of heat radiated from the heat retention heater directly to the thermal reed switch is increased. On the other hand, the distance transmitted in the order of the heat receiving portion, the heat transfer plate, and the thermal reed switch is increased, and the heat transfer amount is reduced. . On the other hand, when the heater is closest to the opposite side of the upper end of the protective frame, the distance between the heater and the thermal reed switch becomes longer,
While the amount of heat directly radiated to the thermal reed switch by the heat retention heater decreases, the distance that the heat receiving section transmits the heat in the order of-heat transfer plate-thermal reed switch becomes shorter,
The amount of heat transfer increases, and as a result, a certain amount of heat is transmitted to the thermal reed switch regardless of the variation position of the heat retaining heater. As a result, the operation of the thermal reed switch is constant, and the heat retention temperature can be stabilized.

Further, by adopting a configuration in which the thermal reed switch, the heat transfer plate and the heat receiving portion thereof are covered with a heat shield plate, even if the heat insulating material provided so as to cover each of the above-mentioned components is removed, the thermal reed switch can be connected to the outside air. Is less affected by the temperature, and the heat retention temperature is stabilized.

Further, the opening angle of the two pieces of the L-shaped frame is
By setting it to 86 ° to 90 °, when the lower piece of the frame is fixed with screws etc., the heat receiving part is pressed against the side of the protective frame, and even if it floats when the heat retaining heater is attached, the heat receiving part presses the heat retaining heater As a result, the relationship between the thermal reed switch and the heat receiving portion is always kept constant, so that the heat retaining temperature is stabilized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, a protective frame 16 is provided inside the main body 15, and a heater 17 and a pan 18 are provided in the protective frame 16. A thermal insulation heater 19 is provided on the upper part of the outer periphery of the protection frame 16 by means such as pasting, and a thermal reed switch 20 for controlling the energization of the thermal insulation heater 19 to be turned on and off is arranged close to the heater.

In the figure, 21 is a center thermometer, 22 is a rice cooking lever, 23 is an operation button, 24 is a changeover switch, and 25 is L
A shaped frame, 26 is a lid. Next, a specific configuration of the protective heater 19 and the related thermal reed switch 20 will be described with reference to FIGS.

The heater 19 disposed on the outer periphery of the protective frame 16 is held down by an aluminum foil 27 with an adhesive. Heat transfer plate
Numeral 28 is formed in a U-shape, and has a trapezoidal heat receiving portion 29 extending upward on both sides thereof. The upper and lower widths of the heat receiving portion 29 are 1 to 4 times the diameter of the heat retaining heater 19, and a wide groove 30 is provided on the protection frame 16 side. Then, the heat receiving portion 29 is brought into contact with the protective frame 16 so that the heat retaining heater 19 is located in the groove 30. The thermal reed switch 20 has a plate-shaped heat-sensitive portion 31 extending downward, and the heat-sensitive portion 31 is overlapped on the heat transfer plate 28. In addition, a heat insulating plate 32 is provided on the heat sensitive part 31.
The heat transfer plate 28, the heat sensitive portion 31, and the heat insulating plate 32
Is attached to a piece of the frame 25 on the side of the protective frame 16 by screws 33 together. The lower piece of the frame 25 is attached to the bottom of the protection frame 16.

Next, the operation of the configuration of the embodiment will be described with reference to FIGS. First, the heat retaining heater 19 is fixed to the protective frame 16 with an adhesive or the like on the back surface of the aluminum foil 27. The positional relationship shown in FIGS. Even if the variation is large, the heat retaining heater 19 enters the inside of the groove 30 of the heat receiving portion 29, and the heat is stably transmitted to the thermal reed switch 20, so that the heat retaining temperature is stabilized.

As shown in FIG. 4, when the heat retaining heater 19 is closest to the upper end of the protective frame 16, that is, when the center of the heat retaining heater 19 and the center of the thermal reed switch 20 are arranged on substantially the same plane, The distance between the heat retaining heater 19 and the thermal reed switch 20 becomes the shortest, and the amount of heat that the heat of the heat retaining heater 19 radiates directly to the thermal reed switch 20 increases.
The distance between the heat receiving portion 29, the heat transfer plate 28, and the thermal reed switch 20 becomes longer, and the amount of heat transferred decreases. On the other hand, as shown in FIG. 6, when the heater 19 is closest to the opposite side of the upper end of the protection frame 16, the heater 19 and the thermal head switch 20 are turned off.
, The amount of heat radiated from the heat retaining heater 19 directly to the thermal reed switch 20 is reduced.
Since the distance transmitted in the order of the heat receiving section 29, the heat transfer plate 28, and the thermal reed switch 20 is shortened, the amount of heat transfer increases, and the amount of heat transfer to the heat retaining heater 19 becomes constant regardless of the position of the heat retaining heater 19. At the position of the heat retaining heater 19 shown in FIG. 5, the heat transfer amount is just intermediate between FIGS. 4 and 6, but the heat transfer amount is almost the same between FIG. 4 and FIG. Calorie. Therefore, even if the attachment of the heat retaining heater 19 to the protection frame 16 has a large variation in the vertical direction, the heat transfer amount of the thermal reed switch 20 is substantially the same, and the variation is eliminated.

FIG. 7 shows another embodiment of the present invention, in which a thermal switch 20 and a heat receiving portion 29 are covered with a heat shield plate 34. In this configuration, the thermal reed switch 20 can be hardly affected by the temperature of the outside air even if the heat insulating material on the outer periphery of the protection frame 16 is removed as shown in the figure, and the heat transfer amount can be further stabilized.

The opening angle of the two pieces of the frame 25 is 86 °.
When the angle is set to 90 °, the heat receiving portion 29 is pressed against the side of the protective frame 16 when the frame 25 is fixed with screws or the like.
When the adhesive 19 is attached, even if it is floating, the heat receiving unit 29 presses the heat retaining heater 19, and the above-mentioned floating can be eliminated.

[0022]

As is apparent from the above description of the embodiment, the present invention can stabilize the heat retaining temperature by making the heat transfer amount constant regardless of the positional relationship between the thermal head switch and the heat retaining heater. Can be. That is, by setting the width of the heat receiving portion in the vertical direction to be 1 to 4 times the diameter of the heat retaining heater, the variation in the mounting of the heat retaining heater on the protection frame can be absorbed even if the dispersion in the vertical direction is large. Can be. In addition, since the center of the heat retention heater and the center of the thermal reed switch are arranged on substantially the same plane, even if the attachment of the heat retention heater to the protection frame varies greatly in the vertical direction, this variation is absorbed and the heat retention temperature is reduced. A stable configuration can be provided. Furthermore, by covering the thermal reed switch and the heat receiving part with a heat shield plate,
Even if the heat shielding material is removed, the thermal reed switch is hardly affected by the temperature of the outside air, and the heat retention temperature can be stabilized. Also, the opening angle of the two pieces of the L-shaped frame is set to 86
By setting the angle between 90 ° and 90 °, it is possible to stabilize the heat retaining temperature even when the heat retaining heater is floating when the heater is attached.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of an electric rice cooker according to one embodiment of the present invention.

FIG. 2 is a perspective view of a main part of the electric rice cooker.

FIG. 3 is a longitudinal sectional view of a main part of the electric rice cooker.

FIG. 4 is a longitudinal sectional view of a main part of the electric rice cooker.

FIG. 5 is a longitudinal sectional view of a main part of the electric rice cooker.

FIG. 6 is a longitudinal sectional view of a main part of the electric rice cooker.

FIG. 7 is a longitudinal sectional view of a main part of an electric rice cooker according to another embodiment of the present invention.

FIG. 8 is a longitudinal sectional view of a conventional electric rice cooker.

[Explanation of symbols]

 16 Protective frame 18 Pot 19 Heat insulation heater 20 Thermal reed switch 28 Heat transfer plate 29 Heat receiving part 31 Heat sensitive part 34 Shield plate

Claims (4)

(57) [Claims] 1. A heating heater is provided on the outer periphery of a protective frame for accommodating a pot.
An electric rice cooker, comprising: an L-shaped heater , one end of which is attached to the bottom of the protective frame and the other end of which is provided.
A protection frame provided with a frame located on the side of the protection frame , wherein the heat retention heater is provided in an attached state;
At the same time as the storage position of the heater.
The width of the protection frame in the vertical direction is one time the diameter of the heat retaining heater.
The heat transfer plate to form a 4 times or less of the groove beyond the provided of the protective frame of the heat transfer plate by the other end of the frame
It is held so as to be located on the outer periphery, and is placed close to the heat insulation heater to control the energization of the heat insulation heater.
A thermal reed switch is provided, and the heat-sensing portion of the thermal reed switch is
Interposed between the other end of the frame and the thermal lead switch.
A heater for an electric rice cooker , wherein the heat-sensitive portion of the switch is thermally coupled to the heat transfer plate . 2. The electric rice cooker according to claim 1, wherein the center of the heater and the center of the thermal reed switch are arranged on substantially the same plane when the heater is closest to the upper end of the protection frame. Heating heater device. 3. The heater device according to claim 1, wherein the thermal reed switch and the heat transfer plate are covered with a heat shield plate. 4. An opening angle of two pieces of the L-shaped frame from 86 ° to 86 °.
The heater device for an electric rice cooker according to claim 1, wherein the heater is set at 90 °.