JP2010214031A - Rice cooker with warmer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a product in a compact size while enough cooling a high frequency power generating element. <P>SOLUTION: A heating means 7 for heating a pot 2 includes: a high frequency power supply means 12; and a cooling fan 11 for cooling the high frequency power supply means 12. The high frequency power supply means 12 includes: the high frequency power generating element 51a; a capacitor 51b for high frequency power; and a heat sink 13 closely adhering to the high frequency power generating element 51a to accelerate radiation of heat. The cooling fan 11 is disposed adjacent to the heat sink 13, a non-combustible cover 52 covering the capacitor 51b for high frequency power is provided at the opposite side to the cooling fan 11 across the heat sink 13, the non-combustible cover 52 is provided with a air reflection plate 52a for changing the air flow direction from the cooling fan 11, and the capacitor 51b for high frequency power is disposed downstream from the air reflection plate 52a. Thus, while the high frequency power generating element is enough cooled, the product can be made in a compact size. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a jar rice cooker used for general household or business use.

  Conventionally, this type of jar rice cooker self-heats both the high-frequency power generating element and the high-frequency power capacitor provided on the circuit board in order to realize induction heating, so that the normal operation of the electronic circuit is maintained. Cooling with a cooling fan is necessary. Among these, the high frequency power capacitor is not shaped to be in close contact with a heat sink or the like as a general-purpose component, and is cooled by directing air from a cooling fan.

Specifically, in the main body of the heating cooker including heating means, a circuit board to which electrical components are attached, a heat sink in which a plurality of fins are arranged in parallel, and a cooling fan for cooling the heat sink are provided, A cooling structure for electrical components, in which specific electrical components are mounted on the heat sink component mounting portion and lead terminals of the specific electrical components are fixed to the circuit board. A cooling fan fan case is mounted on the heat sink, and this cooling A cooling structure for electrical parts, characterized in that a predetermined gap is provided between the front end surface of each fin extending toward the fan blowing direction and the fan case, and the gap is used as a blowing passage from the cooling fan. (For example, refer to Patent Document 1).
JP 2000-332474 A

  However, in the conventional configuration, in order to sufficiently cool the high-frequency power generating element and to obtain a sufficient cooling effect for the high-frequency power capacitor, the arrangement of the high-frequency power capacitors is naturally limited. For this reason, the circuit board becomes unnecessarily large due to the problem of the arrangement of the high-frequency power capacitor. In addition, in order to obtain a sufficient cooling effect, the cooling fan must secure an appropriate air volume. To do so, increase the rotation speed of the cooling fan to ensure the air volume or use a large cooling fan. However, when the number of rotations of the cooling fan is increased, the noise value of the fan operation increases, so the size of the cooling fan can be restricted so that the noise value does not increase, and the product cannot be made more compact than a certain level. Had.

  This invention solves the said conventional subject, and it aims at providing the jar rice cooker which can cool efficiently the high frequency electric power generating element which is a self-heating component, and the capacitor | condenser for high frequency electric power, and can make a product compact. .

  In order to solve the conventional problem, the jar rice cooker of the present invention has a cooling fan that cools the high-frequency power supply means, and the high-frequency power supply means includes a high-frequency power generation element, a high-frequency power capacitor, And a heat sink that is in close contact with the high-frequency power generation element and promotes heat radiation of the high-frequency power generation element, wherein the cooling fan is disposed adjacent to the heat sink, and the cooling fan is sandwiched between the heat sinks. A non-combustible cover that covers the high-frequency power capacitor is provided on the side opposite to the non-combustible cover, a wind direction plate that changes a wind direction from the cooling fan is provided on the non-combustible cover, and the high-frequency power capacitor is disposed downstream of the wind direction plate. is there.

As a result, the high-frequency power generating element can be sufficiently cooled, and a sufficient cooling effect can be obtained without worrying about the arrangement of the high-frequency power capacitor. In addition, the cooling efficiency of the high-frequency power generating element and the high-frequency power capacitor is improved. In order to improve, the product can be made compact because the cooling fan can be miniaturized.

  The jar rice cooker according to the present invention can sufficiently cool the high-frequency power generating element and obtain a sufficient cooling effect without worrying about the arrangement of the high-frequency power capacitor. Since the cooling efficiency of the condenser is improved, the product can be made compact because the cooling fan can be miniaturized.

  The first invention is a detachable pan, a main body having a bottomed cylindrical pan storage part on the upper surface, a heating means for heating the pan, a high-frequency power supply means for supplying high-frequency power to the heating means, A cooling fan for cooling the high-frequency power supply means, the high-frequency power supply means being in close contact with the high-frequency power generation element, a capacitor for high-frequency power, and heat dissipation of the high-frequency power generation element The cooling fan is disposed adjacent to the heat sink, and a non-combustible cover for covering the high-frequency power capacitor is provided on the side facing the cooling fan across the heat sink, The incombustible cover is provided with a wind direction plate that changes the direction of the wind from the cooling fan, and the high frequency power capacitor is disposed downstream of the wind direction plate. In addition to sufficiently cooling the high frequency power generating element, it is possible to obtain a sufficient cooling effect without worrying about the arrangement of the high frequency power capacitor, and the cooling efficiency of the high frequency power generating element and the high frequency power capacitor is improved. Therefore, the product can be made compact because the cooling fan can be miniaturized.

  In the second invention, in particular, the non-combustible cover of the first invention is made of a non-combustible resin material and imparts flame retardancy equivalent to 5VA or more of UL-94, so that the high-frequency capacitor generates heat when it is damaged. In preparation for this, the distance from the surrounding parts to prevent the surrounding parts from being damaged at the same time can be reduced, so that the circuit board can be miniaturized and the product can be made compact. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a rice cooker according to the first embodiment of the present invention, FIG. 2 is a bottom view of the rice cooker according to the first embodiment of the present invention, and FIG. 3 is the first view of the present invention. The perspective view of the high frequency electric power supply means of the rice cooker in embodiment of this, FIG. 4 shows the cover body part sectional drawing of the rice cooker in the 1st Embodiment of this invention.

  In FIG. 1, the rice cooker main body 1 has an outer frame composed of an upper frame 3 constituting an upper surface and a body 4 constituting a side surface and a bottom surface. The upper frame 3 has a cylindrical hole portion 3a, and a cylindrical and metal protective frame body 5 and a dish-shaped protective frame 6 are connected to the hole portion 3a to form a bottomed cylindrical pot storage portion 1a. The pan 2 is stored detachably. The bottom induction coil 7 provided at the bottom of the protective frame 6 serves as a pan heating means, and the pan 2 is induction-heated to cook rice and keep warm.

  Here, a plurality of bottom ferrites 8 made of a magnetic material are provided on the opposite side of the pan 2 in an arrangement facing the bottom induction coil 7 and orthogonal to the bottom induction coil 7.

The bottom sensor 9 is in contact with the bottom surface of the pan 2, detects the temperature of the pan 2, and sends a signal to the microcomputer 10. The microcomputer 10 changes the energization amount of the bottom induction coil 7 from the signal of the bottom sensor 9, and the pan 2
By changing the high-frequency current supplied from the high-frequency power supply means 12 to the bottom induction coil 7, the temperature of the pan 2 is controlled to an appropriate temperature when cooking and keeping warm.

  A reflection frame 32 is provided in an annular shape on the outer periphery of the bottom induction coil 7. A side heater 20 as a side heating means is wound around the outer periphery of the protective frame body 5.

  The high-frequency power supply means 12 blows outside air to the substrate 50 having the pattern surface 50a on one side, the electronic component 51 attached to the surface opposite to the pattern surface 50a, the heat sink 13 made of aluminum or aluminum die-casting, and the heat sink 13. A cooling fan 11 is used. The cooling fan 11 is arranged so that the cooling fan exhaust part 11 a is adjacent to the heat sink 13. The heat sink 13 has a plurality of fins 13a along the blowing direction of the wind from the cooling fan exhaust 11a.

  As shown in FIGS. 1 and 2, a main body inlet 4 a is provided on a surface of the body 4 that incorporates the high-frequency power supply means 12 and faces the cooling fan intake portion 11 b, and sucks outside air from outside the rice cooker main body 1. The air inlet 4a is provided in the shape of a lattice hole in almost the entire region facing the cooling fan air intake portion 11b. There is an exhaust port 4b on the bottom surface of the body 4 and in the vicinity of the position farthest from the main body intake port 4a. In this Embodiment, as shown in FIG. 2, the exhaust port 4b is formed in the position which substantially opposes on both sides of the main body inlet 4a and the rice cooker main body 1 center view by the bottom view of the rice cooker main body 1. As shown in FIG.

  As shown in FIG. 3, the electronic component 51 mounted on the substrate 50 of the high-frequency power supply means 12 includes a high-frequency power generating semiconductor element 51a and a high-frequency capacitor 51b. The high frequency power generating semiconductor element 51 a is disposed in close contact with the heat sink 13.

  The high-frequency capacitor 51b is disposed on the side of the heat sink 13 at a position that is out of the air blowing direction from the cooling fan exhaust 11a. The high frequency capacitor 51 b is covered with a non-combustible cover 52. The incombustible cover 52 has a wind direction plate 52a that takes in the wind from the cooling fan 11 and flows it to the high frequency capacitor 51b. Here, the non-combustible cover 52 is made of a resin material having flame retardancy equivalent to UL-94 of 5 VA or more, and various electronic components are arranged in a portion facing the high-frequency capacitor 51b with the non-combustible cover 52 interposed therebetween.

  In FIG. 1, a hinge portion 14 is provided on the upper surface of the upper frame 3 at the rear of the main body, and a lid 15 is pivotally supported by a hinge shaft 16 attached to the hinge portion 14 so as to freely open and close. Yes. A hinge spring 17 is attached to the hinge portion 14 so as to engage with both the lid body 15 and the main body 1, and has a biasing force in a direction to open the lid body 15. A hinge cover 19 covers the outline of the rear part of the hinge part 14 so that the hinge shaft 16 and the hinge spring 17 cannot be seen from the outside.

  The hook lever 18 in front of the main body is fitted with a hook fitting portion 15a provided at the tip of the lid body 15 so that the lid does not open against the force of the hinge spring 17, and the lid lever 18 is kept closed. When the hook lever 18 is pushed, the hook fitting portion 15 a and the hook lever 18 are disengaged, and the lid is opened by the force of the hinge spring 17.

  As shown in FIG. 4, the surface of the lid 15 is constituted by an outer lid 22, and the pot 2 side is constituted by an outer lid cover 23.

The outer lid cover 23 has a hole in a cylindrical shape, and a steam heating plate 24 made of a non-magnetic metal and a thin plate having a thickness of 0.5 mm or less is attached to the hole. Here, representative examples of nonmagnetic metals include austenitic stainless steel. An annular lid induction coil 26 mounted on a lid coil support 25 is provided on the upper portion of the steam heating plate 24. A lid temperature fuse 27 is installed so as to be sandwiched between the lid coil support 25 and the lid coil 26. A lid reflector 34 is provided above the lid induction coil 26 to prevent the high-frequency magnetic field from the lid induction coil from leaking outside.

  On the pan side of the outer lid cover 23, there is a heating plate 29 made of magnetic metal that is held integrally with the heating plate support 28 by caulking and is detachable from the lid 15 in an integrated state with the heating plate support 28. Typical examples of the magnetic metal include an iron plate and ferritic stainless steel.

  Between the heating plate 29 and the flange portion 2a of the pan 2, a pot packing 31 integrally joined to the heating plate 29 by a heating plate support 28 seals the heating plate 29 and the flange portion 2a of the pan 2 in a watertight manner. Further, a steam heating plate packing 47 is provided between the steam heating plate 24 and the heating plate 29 on the outer peripheral portion thereof, and the space between the heating plate 29 and the steam heating plate 24 is sealed in a watertight manner.

  The lid sensor 30 abuts on the heating plate 29 by pressing with the lid sensor spring 33 and detects the temperature of the heating plate. A lid sensor packing 46 is provided between the lid sensor 30 and the steam heating plate 24.

  Inside the outer lid 22, an operation substrate 35 constituting the operation unit 15 b and the display unit 15 c is installed so as to be covered with a substrate cover 36. A liquid crystal 39 on the operation board 35 displays a setting state and an operation state of the rice cooker. A part of the outer lid 22 is made of a transparent resin, and the surface thereof is integrally covered with a film 22b. And it has the embossed part 22a which consists of a part only of a film partially. The embossed portion 22a bends up and down, and the embossed portion 22a, the key top 37 provided on the operation board 35, and the tact switch 38 constitute an operation switch, and the operation portion 15b is constituted by a plurality of operation switches.

  The substrate cover packing 40 is sandwiched between the outer periphery of the substrate cover 36 and the substrate cover seal rib 22c provided on the outer lid 22, and seals between the substrate cover 36 and the outer lid 22 in a watertight manner. The substrate 35 is prevented from condensing even if the liquid enters.

  A steam passage portion 36 a is provided in the central portion of the substrate cover 36. The steam passage part 36a has a cylindrical shape that penetrates the outer lid and faces the outside, and holds the steam cylinder 41 in a detachable manner. A space between the outer periphery of the steam passage portion 36a and the outer lid 22 is sealed with a steam passage packing 42 in a watertight manner. The operation substrate 35 disposed inside the lid 15 by the seal by the substrate cover packing 40 and the steam passage packing 42 is configured so that water and steam from the outside are not directly applied. The steam plate packing 45 seals the steam passage 36a, the steam heating plate 24, and the heating plate 29 in a watertight manner.

  Next, the operation in the above configuration will be described. The hook lever 18 is pushed, the lid is opened, rice to be cooked and water corresponding to the amount of rice are put into the pan 2 and inserted into a predetermined state of the pan storage portion 1a.

  Subsequently, when the user operates a rice cooking start switch (not shown) of the operation unit 15b, the microcomputer 10 receives an input from the rice cooking start switch, and the rice cooking process is performed. At this time, the operation state is displayed on the liquid crystal 39, the transparent resin on the liquid crystal 39 is transmitted, and the display of the liquid crystal 39 is made visible from the outside so that the display unit 15c is configured. Inform the state.

  The bottom sensor 9 detects the temperature of the bottom surface of the pan 2 and sends a signal to the microcomputer 10. Receiving a signal from the bottom sensor 9, the microcomputer 10 has a predetermined time at a temperature at which the water and rice state in the pan 2 are set as appropriate values in each of the rice cooking processes roughly divided into the water immersion, cooking, and steaming processes. So that the energization amount of the bottom induction coil 7, the lid induction coil 26 and the side heater 20 energized by the high-frequency power supply means 12 is controlled as an output.

  In the induction heating method, when a high-frequency magnetic field generated from a high-frequency current passed through each induction coil passes through the metal to be heated, induction heating is performed to generate heat. Here, in the high-frequency power supply means 12, the high-frequency power generation semiconductor element 51a and the high-frequency capacitor 51b self-heat due to an electrical resistance loss and a switching loss at the time of high-frequency generation when supplying a high-frequency current to each induction coil. However, the high-frequency power generating semiconductor element 51a and the high-frequency capacitor 51b may be destroyed when they become higher than the allowable temperature due to self-heating, and the high-frequency power generating element 51a in particular has a large amount of self-heating. Therefore, the high frequency power generating semiconductor element 51a is in close contact with the heat sink 13 so as not to be destroyed by the heat generated by the self-heating. The heat generated by the self-heating is transferred to the heat sink 13 and is radiated by being cooled by the wind of the cooling fan 11. The high frequency power generating semiconductor element 51a will not be destroyed.

  As described above, although not as high as the high frequency power generating semiconductor element 51a, the high frequency capacitor 51b also generates heat. Therefore, it is necessary to apply the wind of the cooling fan exhaust part 11a to the high frequency capacitor so as not to be destroyed by heat due to self-heating. However, in the case of the conventional configuration as shown in FIG. 5, the position of the high frequency capacitor 61b is limited in the wind blowing direction from the cooling fan exhaust 60a so that the cooling fan 60 can be directly exposed to the wind. End up. In addition, in order to obtain a sufficient cooling effect, the cooling fan must secure an appropriate air volume. To do so, increase the rotation speed of the cooling fan to ensure the air volume or use a large cooling fan. However, if the number of rotations of the cooling fan is increased, the noise value of the fan operation increases, so that the size of the cooling fan can be restricted so that the noise value does not increase, and the product cannot be made more compact than a certain level.

  Here, as shown in FIGS. 1 and 3, in this example, the high frequency capacitor 51 b is disposed on the side of the heat sink 13 and at a position away from the wind blowing direction from the cooling fan exhaust 11 a. The incombustible cover 52 has a wind direction plate 52a that takes in the wind from the cooling fan 11 and flows it to the high-frequency capacitor 51b. Further, the non-combustible cover 52 is made of a resin material having flame retardancy equivalent to 5 VA or more of UL-94, and various electronic components are arranged in a portion facing the high-frequency capacitor 51b with the non-combustible cover 52 interposed therebetween. As a result, the wind from the cooling fan 11 strikes the high-frequency capacitor 51b with the wind direction plate 52a while changing its direction, and the cooling wind can be efficiently applied. In addition to sufficiently cooling the high frequency power generating element, this can provide a sufficient cooling effect without worrying about the arrangement of the high frequency power capacitor, and the cooling efficiency of the high frequency power generating element and the high frequency power capacitor is improved. In order to improve, the cooling fan can be reduced in size. In addition, since the electronic component can be arranged in the immediate vicinity of the high frequency capacitor 51b by blocking with the non-combustible cover 52, the arrangement of the high frequency capacitor 51b is not limited and can be arranged on the high frequency power generating means 12, and as a result, the high frequency power is generated. The means 12 can also be made compact. Therefore, the product can be made smaller.

  The bottom induction coil 7 generates heat at the bottom of the pan 2 by induction heating with a current supplied from the high frequency power supply means 12. Here, the bottom ferrite 8 is made of a magnetic material and efficiently collects the magnetic field generated from the bottom induction coil 7 toward the pan. Thereby, a high-density magnetic field is generated around the pan 2, and the pan generates heat more efficiently. The reflection frame 32 prevents the high-frequency magnetic field from the bottom induction coil 7 from leaking out of the main body 1 and does not affect the surrounding devices.

The lid induction coil 26 causes the steam heating plate 24 and the heating plate 29 to simultaneously generate heat by induction heating with a current supplied from the high-frequency power supply means 12. Here, since the steam heating plate 24 is composed of a non-magnetic metal and a thin plate of 0.4 mm or less as described above, it self-heats by induction heating while transmitting a high-frequency magnetic field generated from the lid induction coil 26. The high frequency magnetic field transmitted through the steam heating plate 24 causes induction heating of the heating plate 29 made of magnetic metal, and causes the heating plate 29 to self-heat. Thereby, the steam heating plate 24 and the heating plate 29 can generate heat simultaneously. The heat generation ratio between the steam heating plate 24 and the heating plate 29 can be arbitrarily set by the distance from the lid induction coil 26, the material properties of the steam heating plate 24, and the plate pressure. The lid reflector 34 above the lid induction coil 26 prevents the high-frequency magnetic field from the lid induction coil from leaking to the outside, and is devised so as not to affect the microcomputer 10 and surrounding devices.

  The side heater 20 self-heats with the current supplied from the high-frequency power supply means 12 and heats the protective frame body. The side surface of the pan 2 is heated by radiant heat and convection heat generated by heating the protective frame body.

  It continues and the operation | movement of the rice cooker in each process is demonstrated. First, in the water immersion process, the bottom induction coil 7 is energized to heat the pan 2 so that the temperature of the rice and water rises to a temperature at which the gelatinization of the rice does not start. Then, the rice is submerged for a predetermined time at a predetermined temperature, and sufficient water absorption is promoted throughout the rice. In the flooding process, it is important to keep the whole rice in the pan 2 uniformly at a target temperature and to keep the water absorption conditions of the rice in the pan 2 uniform in order to cook delicious rice.

  Next, in the cooking process, the bottom induction coil 7 generates heat at the bottom of the pan 2, the lid induction coil 26 generates heat from the steam heating plate 24 and the heating plate 29, and the side heater 20 heats the side of the pan, and the pan 2 Heat to wrap the whole thing. It is important to cook at a stretch with high heat and transfer heat to the core of the rice. The induction heating method can heat the pan with a high heating power compared to the method of heating the pan with a hot plate, and cooks a more delicious rice.

  The steam generated when the water in the pot 2 boils flows from a heating plate steam port (not shown) provided in the heating plate 29 to the steam cylinder 41 of the steam passage portion 36a.

  Also, the pot packing 31 and the steam plate packing 45 do not cause steam to flow out of the steam cylinder 41 or flow into the lid 15.

  Finally, in the unevenness process, the bottom induction coil 7 heats the bottom surface of the pan 2 to such an extent that the rice on the bottom surface of the pan 2 does not dry or burn.

  When cooking is completed, the process proceeds to the heat insulation process. In the heat retaining process, the bottom induction coil 7 heats the pan 2 so as to maintain the temperature of the rice in the pan 2 at a predetermined temperature based on the temperature detected by the bottom sensor 9.

  As described above, in the present embodiment, a detachable pan, a main body having a bottomed cylindrical pan storage portion on the upper surface, a heating means for heating the pan, and high-frequency power is supplied to the heating means. A high-frequency power supply means; and a cooling fan that cools the high-frequency power supply means. The high-frequency power supply means is in close contact with the high-frequency power generation element, the high-frequency power capacitor, and the high-frequency power generation element. A heat sink that promotes heat dissipation of the high-frequency power generating element, wherein the cooling fan is disposed adjacent to the heat sink, and the high-frequency power capacitor is disposed on a side facing the cooling fan with the heat sink interposed therebetween. A non-combustible cover is provided, and a wind direction plate is provided on the non-combustible cover to change the direction of the wind from the cooling fan. By arranging it at the downstream of the plate, it is possible to obtain a sufficient cooling effect without having to worry about the arrangement of the capacitor for high frequency power while sufficiently cooling the high frequency power generating element, as well as the high frequency power generating element and the high frequency power. Since the cooling efficiency of the condenser is improved, the size of the product can be reduced because the cooling fan can be reduced in size.

In the present embodiment, the non-combustible cover is made of a non-combustible resin material, and is provided with a flame retardant equivalent to 5 VA or more of UL-94. Since it is possible to reduce the distance from the surrounding parts for preventing the parts from being damaged at the same time, the circuit board can be reduced in size and the product can be made compact.

  As described above, the jar rice cooker according to the present invention can be made compact while sufficiently cooling the high-frequency power generating element, and thus can be applied to uses such as domestic or commercial rice cookers.

Sectional drawing of the rice cooker in Embodiment 1 of this invention. Bottom view of rice cooker in embodiment 1 of the present invention The perspective view of the high frequency electric power supply means of the rice cooker in Embodiment 1 of this invention Cross-sectional view of the lid part of the rice cooker in Embodiment 1 of the present invention Cross section of conventional rice cooker

DESCRIPTION OF SYMBOLS 1 Rice cooker main body 1a Pot storage part 2 Pot 7 Bottom induction coil (heating means)
DESCRIPTION OF SYMBOLS 11 Cooling fan 12 High frequency electric power supply means 13 Heat sink 51a Semiconductor element for high frequency electric power generation 51b High frequency capacitor 52 Nonflammable cover 52a Wind direction board

Claims (2)

A detachable pan, a main body having a bottomed cylindrical pan storage part on the upper surface, a heating means for heating the pan, a high-frequency power supply means for supplying high-frequency power to the heating means, and the high-frequency power supply means And the high frequency power supply means includes a high frequency power generation element, a high frequency power capacitor, and a heat sink that is in close contact with the high frequency power generation element and promotes heat dissipation of the high frequency power generation element. The cooling fan is disposed adjacent to the heat sink, and provided with a non-combustible cover that covers the high-frequency power capacitor on the side facing the cooling fan with the heat sink interposed therebetween. A wind direction plate that changes the direction of the wind from the cooling fan is provided, and the high-frequency power capacitor is disposed on the downstream side of the wind direction plate. Over rice cooker. The jar rice cooker according to claim 1, wherein the non-combustible cover is made of a non-combustible resin material and imparts flame retardancy equivalent to or higher than UL-94 5VA.

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