JPH0454913A - jar rice cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a jar rice cooker in which food is placed in a pot, heated, and kept warm.

BACKGROUND OF THE INVENTION Jar rice cookers that are generally equipped with an induction heating source and that cook and keep warm the food in the pot include, for example, the Utility Model No. 53-
As shown in Japanese Patent No. 164964, a structure as shown in FIG. 5 is known. That is, in FIG. 5, a cylindrical outer case 101 with open upper and lower surfaces is shown.
A bottom plate 103 having support legs 102 is fixed to the lower surface of the holder with screws. The pot storage section 104 is made of, for example, heat-resistant plastic, and has a flange 104a provided at its upper end that is fixed to the upper surface of the outer case 101 with screws. The heat-retaining heater 105 is located in the pot storage section 1
04 by integral molding, and the induction coil 106 is embedded in the bottom surface 104C of the pot storage section 104.
It is partially buried in the mold. The pot 107 is made of a magnetic material, such as iron, and is removably placed on the bottom surface 104c of the pot storage section 104. The thermostat 108 is fixed in a through hole 104d provided at the center of the bottom surface 104C of the pot storage section 104 via a support plate 109. For example, magnetic thermostat 10
The heat-sensitive portion 108a of No. 8 is urged upward by a spring (not shown) and comes into close contact with the bottom portion 107b of the pot 107.

In the jar rice cooker, this thermostat 108 controls rice cooking and heat retention.

A lid 113 having a knob 114 is removably placed on the flange 104a of the pot storage section 104. Control board 1
15 is fixed to the upper surface of the bottom plate 103, and a part of the electric circuit is disposed therein.

Further, there is a tube 116 at the bottom of the support plate 109, and a number of drain holes 117 are provided in the center of the bottom plate 103 at the bottom.

Problems to be Solved by the Invention In such a conventional jar rice cooker configuration, if water is accidentally put into the pot accommodating portion 104 when the pot 107 is not present,
The control board 115 and internal wiring inside the main body are submerged in water.

In order to prevent such flooding, a large number of drain holes 117 are provided in the center of the bottom plate 117.

However, because this drain hole 117 is located in the bottom plate 103, the cold air inside the room enters through this hole 117,
Since it was cooled, the heat retention performance of pot 107 was poor.

That is, when keeping food such as rice warm, the heat of the rice is transmitted to the bottom of the pot 107, and this conductive heat causes the heat sensitive part 1
08a is heated, and the heat retention temperature is controlled by the temperature of this heat sensitive part 108a.

This insulating temperature is set at 73°C to prevent drying and yellowing at high temperatures and to prevent the growth of germs at low temperatures. but,
The outside temperature changes depending on the season, with room temperature ranging from 35℃ in summer and winter.
It changes to -5℃. Particularly in winter, when the kitchen or the like gets cold to -5°C to -10°C, cold air enters the rice cooker main body through the drain hole 117 and cools the heat-sensitive part 108a. At this time, even if the temperature of the rice is 73°C, the heat-sensitive part 108a is cooled down to about 70°C, so in order to raise the temperature of the heat-sensitive part 108 to 73°C, the induction coil 106, the heat-retaining heater 105, etc. are energized to heat the pot. Heat 107. As a result, the rice temperature rises to 76° C., at which point the heat-sensitive portion 108a reaches 73° C. and stops heating.

When the rice temperature drops, it is heated again and the rice temperature remains at 76°C. The rice kept warm in this way is kept at a high temperature and dries, and the ingredients of the rice decompose and emit heat retaining material, which accelerates yellowing, so there is a problem in keeping it warm for a long time.

The present invention solves these problems, and aims to provide a jar rice cooker that maintains a predetermined insulating temperature regardless of the temperature of the place where it is installed.

Means for Solving the Problem In order to solve this problem, the jar rice cooker of the present invention includes a jar rice cooker main body, a protective frame disposed inside the jar rice cooker main body, and a protective frame that can be freely attached and detached within the protective frame. a pot housed in the protective frame, supported by a sensor tube at the center of the bottom of the protective frame;
A heat-sensitive sensor for detecting the temperature of the pot is provided, and a hole provided at the bottom of the bottomed cylindrical sensor cylinder is opened and closed by a float that freely slides inside the sensor cylinder depending on the water level. .

In addition, the float has a hollow structure so that it floats on water.

Further, a jar rice cooker main body, a protective frame disposed inside the jar rice cooker main body, a pot removably housed in the protective frame, and a sensor tube supported at the center of the bottom of the protective frame, and a heat-sensitive sensor that detects the temperature of the pot,
A bottomed cylindrical drain plate having the same inner diameter as the sensor tube is supported on the open bottom of the sensor tube by a spring.

Function: With this configuration, it is possible to prevent the heat-sensitive sensor of the jar rice cooker from being cooled by outside air, and it is possible to stabilize the heat retention temperature.

In other words, the hole provided in the sensor cylinder is covered by the float or water drain plate when keeping warm, but even if a large amount of water is injected into the rice cooker and flows into the heat-sensitive sensor part, the float When using a float, the float opens a hole in the bottom plate as it floats on the water, and water flows downward through this hole and flows out of the vessel. On the other hand, when a drain plate is used, the weight of the water accumulated on the plate stretches the spring, creating a gap between the drain hole and the bottom plate, allowing water to flow out of the vessel. Once the water has flowed out, the float descends as the water level drops, closing the hole. Furthermore, when the water drains out, the drain plate moves upward under the action of a spring to eliminate the gap, thereby preventing the heat-sensitive sensor section from being cooled by outside air and maintaining an accurate insulating temperature in either case.

Example An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 and FIG. 2 show the structure of a jar rice cooker according to an embodiment of the present invention.

As shown in the figure, inside the approximately cylindrical rice cooker main body 1, a non-metallic protective frame bottom 3a and a metal protective frame side surface constitute a protective frame 3 in which the pot 2 is removably housed. Part 3b
At the same time, an upper frame 5 is provided above the protective frame side portion 3b. The pot 2 is made of, for example, a clad steel plate with a magnetic outer surface, and is supported by placing its upper end flange 6 on an upper frame 5. induction coil 7
is arranged on the outer surface of the protective frame bottom 3a facing the bottom of the pot 2, and is held between it and the protective frame cover 8. A heat-sensitive sensor for detecting the temperature of the pot 2 is pressed into the center of the bottom of the pot.

The lower frame 10 constitutes the lower part of the cooking device main body 1, and the sensor tube 11 that supports the thermal sensor 9 is provided between the lower frame 10 and the protective frame cover 8, and the sensor tube 11 has a plurality of holes 12 at the bottom. It is provided. The float 13 has a donut shape and closes the hole 12 with its outer peripheral surface. Further, the float 12 is configured to float on water with a specific gravity lower than that of water, and may be made of expanded polystyrene, expanded PP, etc., and may have a solid structure instead of a donut shape as long as the specific gravity is 1 or less. Further, the dimensions of the float 12 are set so that it can freely slide up and down within the sensor cylinder 11. When the float 12 is made of a material with a specific gravity of 1 or more, it may be made hollow by blow molding, or when a material with low thermal conductivity such as glass or ceramic is used, it may be made hollow so that the appearance of floating on water is due to its density. It is sufficient if it is configured so that

Further, for example, a coated and insulated heater 14 is attached to the side surface portion 3b of the protective frame. Further, a control board 15 is fixed to the upper surface of the lower frame 10, and a part of an electric circuit is disposed on this control board 15.

A lid 16 made of resin is supported on the upper part of the upper frame 5 of the rice cooker main body 1 by a hinge part 17 formed integrally with the upper frame 5 via a pin 18 so as to be openable and closable. Lid body 1
A handle portion 19 is provided on the top surface of the device 6, and an inner cover 20 is fixed to the inner surface via a heat insulating material 21.

A contact 23 with which a thermistor 22 in the heat sensitive sensor 9 is in thermal contact is biased by a sensor spring 24 and comes into contact with the bottom of the pot 2 to sense the temperature of the pot 2. Further, temperature information sensed by the thermistor is transmitted to an electric circuit (not shown) to control the power of the induction coil 7 and heater 14.

Next, the operation of the jar rice cooker having the above structure will be explained. For example, when cooking rice, put an appropriate amount of rice and water into the pot 2, press a switch on the operation panel (not shown), and turn on the power. By electrically controlling the induction coil 7 and heater 14, rice can be cooked and kept warm.

Further, during heat retention, the float 13 is placed downward due to gravity, and the hole 12 is closed to prevent outside air from entering, so the thermistor 22 is not affected by the outside air.

On the other hand, when pot 2 is not installed, a large amount of water leaks into protective frame 3.
Once inside, the water flows downward along the inner circumferential side of the sensor tube 11 through the gap between the contact 23 and the protective frame bottom 3a, and as shown in FIG. 2, the float 13 floats on the water and rises, passing through the hole 12. When opened, water is discharged from the main body through this hole 12, and the power supply section inside the main body is safely held.

Other embodiments of the present invention are shown in FIGS. 3 and 4.

FIG. 3 shows the structure of a jar rice cooker according to another embodiment of the present invention.
FIG. 4 shows the configuration of the heat-sensitive section at the bottom of the rice cooker.

In FIGS. 3 and 4, the same components as those in FIGS. 1 and 2 are designated by the same reference numerals, and their explanations will be omitted.

Sensor tube A11. In the open bottom part 25 of a, there is a sensor cylinder A1.
A bottomed cylindrical drainage plate 26 with the same inner diameter as 1a is supported on the sensor m 11 a by a spring 27 with a sufficiently light load.

The operation of the jar rice cooker with this configuration will be explained. During heat retention, the water drain plate 26 comes into contact with the sensor tube 11a to prevent outside air from entering. On the other hand, if a large amount of water flows into the protective frame 3 with the pot 2 not installed, the water will flow through the sensor cylinder 1a from the gap between the contact 23 and the protective frame bottom 3a and onto the drain plate 26. When the water accumulates and the gravity of the water exceeds the biasing force of the spring 27, the drain plate 26 moves downward and opens the bottom to form a drain hole 12a, from which the water is drained. The drain plate 26, whose weight has been reduced by draining water, closes the bottom 25 of the drain plate 26 by the biasing force of the spring 27, thereby preventing outside air from entering.

Effects of the Invention As is clear from the description of the embodiments above, according to the jar rice cooker of the present invention, the intrusion of water is detected by using a float and a spring through the hole arranged at the bottom of the sensor cylinder, and the intrusion of water is detected. Drainage holes are formed only when

As a result, under normal conditions, the drain holes are shielded to prevent cold air from entering, which prevents the heat-sensitive parts from cooling due to outside air intrusion, making it possible to maintain a constant insulating temperature. This has the effect of realizing an excellent heat retention effect that prevents rice from drying out or turning yellow over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a jar rice cooker according to an embodiment of the present invention;
FIG. 2 is a longitudinal cross-sectional view of the same essential parts, FIG. 3 is a longitudinal cross-sectional view of a jar rice cooker according to another embodiment of the present invention, and FIG. 4 is a longitudinal cross-sectional view of the same essential parts.
FIG. 5 is a longitudinal sectional view of a conventional jar rice cooker. 1...Jar rice cooker body, 2...Pot,
3...Protection frame, 9...Detection sensor, 1
1... Sensor tube, 11a... Sensor tube A, 12... Hole, 13... Float,
26... Drain plate, 27... ノ(ne. Name of agent Patent attorney Shigetaka Awano 1 person 1a Sensor tube A Collection 3 Figure Spring Figure 4

Claims (3)

[Claims] (1) A jar rice cooker main body, a protective frame disposed inside the jar rice cooker main body, a pot removably housed in the protective frame, and a sensor cylinder supported at the center of the bottom of the protective frame. , comprising a heat-sensitive sensor that detects the temperature of the pot,
A jar rice cooker in which a hole provided at the bottom of the bottomed cylindrical sensor cylinder is opened and closed by a float that freely slides inside the sensor cylinder depending on the water level. (2) The jar rice cooker according to claim 1, wherein the float has a hollow structure so that it floats on water. (3) A jar rice cooker main body, a protective frame disposed inside the jar rice cooker main body, a pot removably housed in the protective frame, and a sensor tube supported by a sensor tube at the center of the bottom of the protective frame. , comprising a heat-sensitive sensor that detects the temperature of the pot,
A rice cooker comprising: a bottomed cylindrical drainage plate having the same inner diameter as the sensor tube; and a drain plate supported on the sensor tube by a spring at an open bottom of the sensor tube.