JP5534824B2 - rice cooker - Google Patents

Description

  The present invention relates to a rice cooker. In particular, the present invention relates to a rice cooker that can prevent the spread of fire against ignition from a control board and efficiently cool a heating element mounted on the control board.

  In general, rice cookers are equipped with electronic components and heat generating elements on the control board, and in order to cool the heat generating elements, the heat generating elements are brought into contact with the heat radiator, and the outside air is sucked from the air intake port provided in the main body by the cooling fan. The control board is cooled and then exhausted from the exhaust port.

  In a conventional rice cooker, a heat sink that cools a heating element and a control board on which electronic components are mounted are attached to a board holder made of a plastic material (see, for example, Patent Document 1).

Japanese Patent No. 4189772 (FIG. 1)

  In the rice cooker of Patent Document 1, electronic components and heating elements are mounted on the control board, and in order to cool the heating elements, the heating elements are brought into contact with the radiator, and further, from a suction port provided in the main body by a cooling fan. Outside air is inhaled, the control board is cooled, and then exhausted from the exhaust port. However, when an electronic component or a heating element becomes abnormal, for example, the heating element becomes high in temperature, and there is a risk that smoke may be emitted from surrounding flammable molded parts or the like, and fire may spread and spread.

  The present invention has been made to solve the above-described problem, and prevents the occurrence of fire spreading such as smoke and fire of other members due to an abnormality of the control board, and a heating element mounted on the control board is provided. It aims at providing the rice cooker which can be cooled efficiently.

A rice cooker according to the present invention includes a control board having a heating element that controls energization with respect to a heating means for heating an inner pot housed in a main body, a cooling fan that sends air to the control board, and a metal member. is configured, a substrate holder for mounting the control board inside the body, formed of a metal member, a cooling fan and covers the entire control board to the substrate holder and co, the metal barrier to form a space on the control board around And a radiator for dissipating the heat generated by the heating element, and a part of the radiator is in contact with the metal barrier so as to be able to conduct heat.

  According to the present invention, since the periphery of the control board is covered with the metal barrier and the substrate holder of the metal member, for example, even if the heating element is ignited abnormally, it is possible to prevent the fire from spreading to the surrounding molded product. it can.

It is a longitudinal cross-sectional view of the rice cooker which concerns on embodiment of this invention. It is the longitudinal cross-sectional view which expanded the control board attachment part partially. It is a disassembled perspective view which shows the structure of a control board attachment part. It is a figure showing the path | route of the intake air path 19 inside a rice cooker.

Embodiment 1 FIG.
Drawing 1 is a figure showing the longitudinal section of the rice cooker concerning an embodiment of the invention. Here, the description will be made assuming that the left side in FIG. 1 is the front side of the rice cooker and the right side is the rear side. In FIG. 1, a rice cooker main body 1 (hereinafter simply referred to as a main body) has a side surface constituted by a cylindrical outer frame 8, and is fixed by sandwiching an upper frame 4 and a bottom plate 9.

  Further, an inner pot storage portion 7 including a cylindrical inner heat shield 5 and a substantially deep dish-shaped coil base 6 provided therebelow is provided inside the main body 1. The inner pot 2 can be detachably stored in the inner pot storage portion 7 from the annular opening of the upper frame 4. The inner pot 2 is formed in a bottomed cylindrical shape, and can accommodate rice and water to be cooked inside, for example, when cooking rice.

  The inner heat shield 5 is attached with a body heater 5a as a heating means in close contact with the outer surface, and is energized during rice cooking and heat retention to generate heat. An induction heating coil 10 as a main heating means is wound around and fixed to the outer surface (bottom part and corner part) of the coil base 6 to generate an alternating magnetic field by energization and heat the inner pot 2 by electromagnetic induction. . In addition, a temperature sensor 11 that detects the temperature of the inner pot 2 by being in contact with the bottom of the inner pot 2 is provided at the center of the coil base 6.

  FIG. 2 is an enlarged view of a front inner portion of the rice cooker according to the present embodiment. In the rice cooker of this Embodiment, the control board 15 is provided in the front inner side part between the outer frame 8 and the inner pot accommodating part 7 in the main body 1. FIG. The control board 15 is equipped with a control unit for controlling energization to the induction heating coil 10. The control unit is composed of, for example, a heating element 17 such as a switching element. In addition, a substrate holder 12 for fixing the control substrate 15 is provided at a position close to the inner pot storage unit 7. In the present embodiment, the substrate holder 12 is made of a metal member.

  Further, the control board 15 is covered with the substrate holder 12 except for the side where air from the cooling fan 18 flows (opened to form the intake air passage 19) (the control board 15 is isolated from other members). The metal barrier 16 is attached as follows. At this time, the metal barrier 16 forms a space around the control board 15 as a space for the intake air passage 19. The metal barrier 16 is provided with an air hole 33 serving as an opening for allowing the intake air passage 19 to communicate with the outside of the metal barrier 16 in a part (here, on the front side).

  In addition, in order to perform heat exchange in which heat generated by the heating elements 17 on the control board 15 is efficiently absorbed into the air by the cooling fan 18, the radiator 20 includes a plurality of radiation fins 20a arranged at predetermined intervals. A part of the container 20 is brought into contact with the control board 15 (heating element 17) and the metal barrier 16. In order not to block the air flow formed by the rotation of the cooling fan 18, the heat radiation fins 20 a made of an aluminum alloy having a good heat conductivity are arranged so as to be substantially parallel to the air flow. Pass between 20a. This air path is part of the intake air path 19. The configuration centered on the control board 15, the metal holder 12, the metal barrier 16, and the like will be described later.

  An air inlet 22 is provided on the front side of the bottom surface of the bottom plate 9, and a cooling fan 18 is installed between the control board 15 and the air inlet 22. An exhaust port 23 is provided on the rear side of the bottom plate 9. The air path until the air sucked from the intake port 22 is discharged from the exhaust port 23 by the rotation of the cooling fan 18 becomes the intake air passage 19.

  On the upper part of the metal barrier 16 (substrate holder 12), an operation substrate attaching portion 13 is provided, and the operation substrate 14 is attached to be inclined. An operation panel 21 including a selection button such as a menu and a rice cooking button is provided above the operation board 14.

  Further, a cord reel 24 having a power cord and a power plug is vertically installed on the rear side of the main body 1, and a leg portion 25 (front leg portion 25a, rear leg portion) for supporting the rice cooker is provided on the bottom plate 9. 25b) are provided at two locations on the front and rear sides.

  The lid body 26 is supported at the rear end portion by a hinge 27 on the upper rear side of the rice cooker, so that the opening of the upper frame 4 can be freely opened and closed. The lid body 26 includes an upper lid 26a that forms an upper surface, and a lower lid 26b that is fixed to the lower side of the upper lid 26a. The front end portion of the lid body 26 is locked by the locking button 3 when the opening of the upper frame 4 is closed.

  A lid cartridge 26 (steam passage body) 28 communicates with the inner pot 2 to separate the steam and steam generated in the inner pot 2 during rice cooking, and discharges the steam outward. Removably mounted. Moreover, the inner surface 29 which has a steam hole in the lower surface of the cover body 26 and covers the upper surface opening part of the inner pot 2 is attached so that attachment or detachment is possible.

  In general, the cartridge 28 is detachably attached to a recess formed in the upper lid 26a and having an upper surface opened. The cartridge 28 includes a lower case (steam passage body) 28a and an upper case (steam passage cover) 28b. These constitute an upper and lower integrated steam discharge device having a steam passage. The lower case 28a is formed in a substantially funnel shape, and is provided with a return tank (tank portion) 30 at a substantially central position, and a return valve for returning the return into the inner pot 2 (see FIG. (Not shown) is provided. The return tank 30 is provided with an introduction cylinder 32 along which the steam from the inner pot 2 flows along the rear wall surface of the vertical wall.

  A steam port 34 for discharging steam to the outside of the main body is formed on the upper surface of the upper case 28b. The upper case 28b and the lower case 28a form a toy separation space partitioned by a plurality of barriers, and the toy and the steam introduced from the introduction tube 32 are separated. A hole 31 is provided on the lower surface of the lid 26 so as to communicate with the cartridge 28 when steam generated during rice cooking is used.

  FIG. 3 is an exploded perspective view showing a mounting portion of the control board 15. Based on FIGS. 1 to 3, the mounting structure of the control board 15 and the relationship between the heating element 17 on the control board 15, the radiator 20 that cools the heating element 17, and the cooling fan 18 will be described in detail.

  In the present embodiment, the control board 15 is attached to the board holder 12 as described above. Here, the back surface (solder surface) of the control substrate 15 and the substrate holder 12 face each other. Since the substrate holder 12 is a metal member, it is desirable to ensure insulation between the solder portion (conductive member) attached to the control substrate 15 and the substrate holder 12. For this reason, instead of directly attaching the control board 15 to the board holder 12, a space may be formed via a spacer or the like, or the control board 15 may be attached to the board holder 12 via an insulator such as a resin. . For example, when a space is formed, the back surface side of the control board 15 is also cooled by the air from the cooling fan 18 passing through the space. In addition, by attaching through an insulator, foreign matter does not enter the back surface of the control board 15, and it is possible to suppress the intrusion of moisture, the occurrence of condensation, etc., so that it is possible to prevent ignition due to a short circuit or the like. it can. In this way, by attaching the control board 15 to the board holder 12 made of a metal member, even if the control board 15 ignites due to a failure or the like, the board holder 12 prevents the rice cooker from spreading to other components. be able to.

  The control board 15 is covered with the board holder 12 and the metal barrier 16 except for the side where the cooling fan 18 is provided (the side that becomes the intake air passage 19). By covering the control board 15 with a metal member, even if the control board 15 is ignited due to a failure or the like, the expansion of the flame is prevented and the spread of fire is prevented.

  Further, as described above, the radiator 20 provided with the heat generating element 17 and the plurality of radiating fins 20a is mounted on the control board 15, and the intake air passage 19 is formed so as to pass between the radiating fins 20a. . The heat generated by the heat generating element 17 is transmitted to the radiator 20 and the heat transfer area is increased by the heat radiating fins 20a, whereby the amount of heat related to heat exchange with the air passing through the intake air passage 19 can be increased. Further, a part of the radiator 20 and the metal barrier 16 are in contact with each other, and the heat generated by the heating element 17 is transmitted to the metal barrier 16 via the radiator 20, thereby increasing the heat transfer area. 16 can also be used.

  FIG. 4 is a diagram showing the path of the intake air path 19 inside the rice cooker. As for the intake air passage 19, an intake air passage for outside air taken in from the intake port 22 provided on the front side of the bottom surface of the bottom plate 9 by the rotation of the cooling fan 18 will be described. The outside air taken in from the air inlet 22 is sent to a space formed by the metal barrier 16 provided with the control board 15 and the metal holder 12. The sent outside air passes between the radiating fins 20a, absorbs heat generated by the heat generating elements 17 and the like, and passes through the air holes 33 above the metal barrier 16. Since the upper part in the rice cooker is closed by the upper frame 4 or the like, the air that has passed through the air holes 33 flows to the bottom of the main body 1. And between the bottom part of the main body 1 and the bottom plate 9, it passes from the front part side to the rear part side. Is discharged outside.

  The rice cooking operation | movement in the rice cooker comprised as mentioned above is demonstrated. When cooking rice, first, the inner pot 2 containing a predetermined amount of rice and water is accommodated in the inner pot accommodating portion 7 (in the main body 1), and the lid body 26 is closed. Further, when the rice cooker is turned on and the rice cooking key on the operation panel 21 provided on the front side of the main body 1 is pressed, the control unit of the control board 15 provided in the main body 1 performs the rice cooking operation process. Do.

  In response to an instruction from the control unit, the heating element 17 that is a switching element is operated to energize the induction heating coil 10 to generate an eddy current on the bottom surface of the inner pot 2 to heat the inner pot 2 and start the rice cooking operation. During the rice cooking operation, the temperature sensor 11 detects the temperature of the inner pot 2, and based on this detected temperature, the control unit controls energization to the induction heating coil 10, and performs the preheating, rice cooking, and unevenness processes. Then cook the rice in the inner pot 2.

  On the other hand, when the rice cooking process is started, the cooling fan 18 is also energized. The cooling fan 18 sucks outside air through an air inlet 22 provided in the bottom plate 9 and sends it out to the control board 15 side. The outside air flows between the fins 20a and cools the heating elements 17 and the like on the control board 15 located above the intake ports 22. Furthermore, it flows in the lower part of the main body 1 to cool the induction heating coil 10 and the like, lowers the surface temperature thereof, and is discharged to the outside of the main body 1 from the exhaust port 23 provided in the rear lower surface of the bottom plate 9.

  The water etc. in the inner pot 2 boil in the above rice cooking process. The rice cartridge 28 introduces a rice ball and steam generated by an increase in the internal pressure of the inner pot 2 from an introduction cylinder 32 communicating with the inside of the inner pot 2 through the hole 31 of the inner lid 29. The rice cracker and steam are separated in a separation space. Then, only the steam is discharged from the steam port 34 to the outside of the lid body 26, and the remaining rice cake is stored in the return tank 30. And when boiling stops and the internal pressure of the inner pot 2 falls, a rice ball will be returned in the inner pot 2 from the hole part 31 provided with the return valve.

  When said rice cooking process is complete | finished, a control part performs a heat retention process process, heats the trunk | drum heater 5a etc., and heats the cooked rice in the inner pot 2. FIG.

  As described above, according to the rice cooker of the present embodiment, the control board 15 is attached to the board holder 12 made of a metal member. Even if ignited from the surface), it is possible to prevent the spread of fire without expanding the flame or the like. At this time, since the substrate holder 12 also serves as a barrier against the spread of fire, the number of parts can be reduced, so that the cost can be reduced. Further, since the periphery of the control board 15 is covered with the metal barrier 16, it is possible to prevent the fire spreading from the control board 15 or the like due to an abnormality of the heating element 17 as in the case of the board holder 12. it can.

  Further, since a part of the radiator 20 for radiating the heat from the heating element 17 and the metal barrier 16 covering the periphery of the control board 15 are brought into contact with each other, the heat from the heating element 17 is transferred to the radiator 20. By transmitting to the metal barrier 16 having good heat conduction, the heat transfer area is further expanded, so that heat can be efficiently dissipated and the cooling effect can be improved. For this reason, the heat radiator 20 can be reduced in size, and it can contribute to size reduction of a rice cooker.

Embodiment 2. FIG.
Although not particularly shown in the above embodiment, at least one material of the metal barrier 16 or the substrate holder 12 may be a nonmagnetic material. For example, by using a non-magnetic material as a metal such as an aluminum material or an alloy containing aluminum, the magnetic field related to the magnetic force generated by the induction heating coil 10 can be cut off. Heat generation, malfunction, etc. of parts can be prevented.

  In the first embodiment, the radiator 20 that cools the heat generating element 17 on the control board 15 is brought into contact with the metal barrier 16. However, the radiator 20 may be brought into contact with the metallic board holder 12. . In consideration of assembly, the substrate holder 12 and the metal barrier 16 are separated from each other, but may be integrally formed. Moreover, it can apply also to the rice cooker of structures other than the rice cooker of the structure of FIG.

  DESCRIPTION OF SYMBOLS 1 Main body (rice cooker main body) 2, Inner pan, 3 Lock button, 4 Upper frame, 5 Inner heat shield, 6 Coil stand, 7 Inner pan accommodating part, 8 Outer frame, 9 Bottom plate, 10 Induction heating coil (heating) Means), 11 temperature sensor, 12 substrate holder, 13 operation board mounting part, 14 operation board, 15 control board, 16 metal barrier, 17 heating element, 18 cooling fan, 19 intake air passage, 20 radiator, 20a radiation fin, 21 Operation Panel, 22 Inlet, 23 Exhaust, 24 Cord Reel, 25 Leg, 25a Front Leg, 25b Rear Leg, 26 Lid, 26a Upper Lid, 26b Lower Lid, 27 Hinge, 28 28a lower case, 28b upper case, 29 inner lid, 30 spring return tank, 31 hole portion, 32 introduction tube, 33 air hole.

Claims (4)

A control board having a heating element that controls energization with respect to a heating means for heating the inner pot housed in the main body;
A cooling fan for sending air to the control board;
A substrate holder made of a metal member for mounting the control board inside the main body,
Formed of a metal member, the cooling fan and covers the entire front Symbol control substrate to the substrate holder and co, the metal barrier to form a space around the control board,
A rice cooker comprising: a heat radiator for dissipating heat generated by the heat generating element , wherein a part of the heat radiator is in contact with the metal barrier so as to be able to conduct heat . Cooker according to claim 1, wherein at least one of the substrate holder or the metal barrier is a non-magnetic material. The rice cooker according to claim 2 , wherein the nonmagnetic material is aluminum. The said metal barrier has an air hole which discharges the air sent in order to exhaust the heat | fever of the said space, The rice cooker in any one of Claims 1-3 characterized by the above-mentioned.

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