JPH0613721U - Induction heating rice cooker - Google Patents

Abstract

(57) [Abstract] [Purpose] By forming the coil at the center of the induction heating coil into a close winding, the surface state of the cooked rice is made substantially flat and a uniform cooked state is obtained. [Structure] An inner pot 10 made of a magnetic material is housed in the rice cooker body 1, an induction heating coil 7 is provided below the inner pot 10, and a coil of a central portion 7a of the coil 7 is formed in a tight winding. The magnetic flux density of the central portion 7a of 7 is increased to diffuse the convection of water in the inner pot 10 from the central portion to the surroundings to perform uniform induction heating.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 According to the present invention, an inner pot made of a container-shaped magnetic material with an open top is detachably installed in the rice cooker body, and an induction heating coil is installed to induction-heat the bottom of the inner pot to cook rice. The present invention relates to an induction heating type rice cooker.

[0002]

[Prior art]

 An example of a conventional induction heating rice cooker will be described with reference to FIG. The conventional induction heating type rice cooker is composed of a rice cooker body 31 and a lid body 32, and the rice cooker body 31 is composed of an outer case 33, a side case 34, a bottom pot 35, and an upper ring 36. . The induction heating coil 37 is disposed below the bottom pot 35 and between the base 38, and the ferrite 39 is disposed below the induction heating coil 37 to improve efficiency and prevent leakage of magnetic flux. It was An inner pot 40 made of a magnetic material is detachably housed inside the rice cooker body 31, and the temperature of the inner pot 40 is detected at the center of the bottom pot 35. The heat-sensitive element 41 was provided.

A control circuit 42 that supplies a high-frequency current to the induction heating coil 37 to generate magnetic lines of force is provided below the base 38, and in order to cool the components of the control circuit 42. The cooling fan motor 44 having the cooling fan 43 is provided in the above. Inside the rice cooker main body 31, a power cord reel 46 for winding and storing the power cord 45 was provided. Further, an inner lid 47 for opening and closing the upper surface opening of the inner pot 40 and a packing 48 for sealing steam are attached to a lid cover 49, the lid cover 49 is attached to the lid body 32, and the lid body 32 is attached. Was opened and closed in the rice cooker main body 31.

In the induction heating type rice cooker having the above configuration, when rice and water are put into the inner pot 40 to start rice cooking, the control circuit 42 supplies a high frequency current to the induction heating coil 37, and the induction heating coil 37 Generate magnetic lines of force. The lines of magnetic force heat the rice and water in which the inner pot 40 is induction-heated, and when the water disappears due to the heating, the bottom temperature of the inner pot 40 rises sharply and the bottom temperature of the inner pot 40 rises. When the heat sensitive element 41 detects that the temperature has risen to 100 ° C. or higher, the high frequency current to the induction heating coil 37 is cut off and the rice cooking operation is completed. When the rice cooking operation is completed and the heat retaining operation is started, the heat retaining heater 50 provided above the side case 34 is energized to keep the temperature.

Further, there is an induction heating type rice cooker as disclosed in JP-A-2-24988. This induction heating type rice cooker includes a substantially concave container for containing rice and water, an induction heating coil for induction heating the container, and a control unit for controlling power supply to the induction heating coil. The heating coil includes a first induction heating coil arranged near the center of the bottom surface of the container, and a second induction heating coil arranged on the lower side surface of the container and the outer peripheral portion of the bottom surface with a gap between the first induction heating coil and the first induction heating coil. Then, an opening is formed at the center of the first induction heating coil, and the heat sensitive element is provided in this opening.

Further, there is an induction heating type rice cooker as disclosed in Japanese Patent Laid-Open No. 3-30718. This induction heating type rice cooker is equipped with a pan to be stored in the rice cooker body and a sensor part that senses the temperature at the center of the pan bottom. In addition to this, the induction heating coil was provided facing this inclined portion.

[0007]

[Problems to be solved by the device]

 First, in the induction heating type rice cooker shown in FIG. 3, only the portion directly above the intermediate portion of the induction heating coil has a temperature distribution as shown by the inclined portion in FIG. As shown by the arrow in Fig. 3, the convection of the water inside becomes the convection toward the center and the periphery of the inner pot, the water temperature on the middle part of the induction heating coil rises quickly, and the rice in this part absorbs much water. The rice cooks well and the surface becomes uneven, and the rice on the middle part of the induction heating coil becomes sticky, while the rice on the other parts becomes hard and the rice is cooked well. I couldn't.

Further, in the case of the induction heating type rice cookers disclosed in Japanese Patent Laid-Open Nos. 2-24988 and 3-30718, the temperature rise in the surroundings is larger than the temperature rise in the central portion of the inner pot. As a result, convection from the periphery of the inner pot to the center occurred, and a recess was formed in the center of the cooked surface. This center became hard rice and it was not possible to obtain a good finish.

The induction heating type rice cooker of the present invention has been made in view of the above problems, and by forming the coil at the center of the induction heating coil in a close winding, the surface state of the cooked rice is made substantially flat. The purpose is to obtain a uniform cooked state.

[0010]

[Means for Solving the Problems]

 In order to achieve the above object, the induction heating type rice cooker of the present invention is configured such that an inner pot made of a container-shaped magnetic material with an open top is detachably housed in the rice cooker body, and the bottom of the inner pot is detached. An induction heating coil for heating rice by induction heating is provided, and the coil at the center of the induction heating coil is formed in a tight winding.

[0011]

[Action]

 In the induction heating type rice cooker with the above configuration, the magnetic flux density in the central part of the induction heating coil is high, the temperature rise in the central part of the inner pot is faster than other parts, and the convection of water is in the central part of the inner pot. The surface of the cooked rice is spread to the surroundings, and the central part of the cooked rice is swollen.

[0012]

【Example】

 An embodiment of the induction heating type rice cooker of the present invention will be described with reference to FIGS. 1 and 2. The induction heating type rice cooker of the present invention comprises a rice cooker body 1 and a lid body 2, and the rice cooker body 1 is composed of an outer case 3, a side case 4, a bottom pot 5 and an upper ring 6. There is. The induction heating coil 7 is arranged below the bottom pot 5 and the base 8, and a ferrite 9 is arranged below the induction heating coil 7 in order to improve efficiency and prevent leakage of magnetic flux. It

The induction heating coil 7 is formed by closely winding a coil for inductively heating the center (center) of the inner pot 10 made of a magnetic material that is detachably accommodated in the rice cooker body 1. It is composed of a part 7a and a peripheral part 7b for inductively heating the bottom part of the inner pot 10. Further, a heat sensitive element 11 that comes into contact with the side bottom portion of the inner pot 10 to detect the temperature is provided on the side portion of the bottom pot 5.

A control circuit 12 for supplying a high-frequency current to the screw induction heating coil 7 to generate a magnetic field line is provided below the base 8 and in order to cool parts of the control circuit 12. A cooling fan 14 having a cooling fan 13 is provided. A power cord reel 16 for winding and storing the power cord 15 is provided inside the rice cooker body 1. Further, an inner lid 17 for opening and closing the upper opening of the inner pot 10 and a packing 18 for sealing steam are attached to a lid cover 19, and the lid cover 19 is attached to the lid body 2. 2 is provided on the rice cooker body 1 so as to be freely opened and closed.

The operation of the induction heating type rice cooker having the above configuration will be described. First, when a predetermined amount of rice and water are put into the inner pot 10 and the inner pot 10 is placed on the bottom pot 5 and stored in the rice cooker body 1, the lid 2 is formed and the rice cooking operation is started. The circuit 13 supplies a high-frequency current to the induction heating coil 7, and the induction heating coil 7 generates magnetic lines of force, and the magnetic lines of force induce induction heating of the inner pot 10 to cook rice.

At this time, the magnetic flux density in the central portion of the induction heating coil 7 becomes high, and the temperature distribution becomes as shown by the hatched portion in FIG. 1, and the temperature rise in the central portion of the inner pot 10 is higher than that of other portions. The flow is largely convective from the center of the inner pot 10 to the surroundings as shown by the arrow in FIG. 1 and diffused to the surroundings, so that uniform rice can be cooked without unevenness and the surface condition after cooking is also good. A flat state with a slightly bulged central part is obtained, and a cooked state with a good appearance can be obtained.

When the heat-sensitive element 11 detects the rice cooking end temperature, the control circuit 12 stops the supply of the high frequency current to the induction heating coil 7, ends the rice cooking operation, and then keeps the cooked rice warm. When necessary, the control circuit 12 energizes the heat retaining heater 20 to retain heat.

[0018]

[Effect of device]

 Since the induction heating type rice cooker of the present invention is configured as described above, the convection of water can be diffused from the center of the inner pot to the surroundings, and a uniform cooked state without unevenness in cooking can be obtained. In addition, even in the case of the surface state after being cooked, the central portion can be made into a flat state with a little swelling, and the appearance can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an induction heating type rice cooker of the present invention.

FIG. 2 is a perspective view showing an induction heating coil of the induction heating type rice cooker of the present invention.

FIG. 3 is a cross-sectional view showing an example of a conventional induction heating rice cooker.

[Explanation of symbols]

 1 Rice cooker body 7 Induction heating coil 7a Central part 7b Peripheral part 10 Inner pan

Continued Front Page (72) Takashi Tanaka 22-22 Nagaikecho, Abeno-ku, Osaka, Osaka Prefecture

Claims (1)

[Scope of utility model registration request] 1. An induction heating coil is provided in the rice cooker body, in which an inner pan formed of a container-like magnetic material having an open top is detachably accommodated, and the bottom of the inner pan is induction-heated to cook rice. In the induction heating type rice cooker, a coil at the center of the induction heating coil is formed in a close winding.