JP2004172138A - Induction heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure capable of sufficiently cooling a drive circuit board even if the drive circuit board is stacked in multistage on one side of an induction heating cooker. <P>SOLUTION: The cooking device comprises an induction heating coil 8; a power supply part 19 having drive circuit boards 10a and 10b equipped with drive circuits 9a and 9b provided in conformation to the induction heating coil 8, which are stacked in two stages; and a scirocco fan 22 for blowing cooling air to the drive circuit boards 10a and 10b and the induction heating coil 8. The scirocco fan 22 has intake ports 24 and 25 on both upper and lower parts and a partitioning plate 26 for partitioning the intake airs from the upper and lower parts. According to this structure, since the partitioning plate 26 part having the largest cooling air quantity can be conformed to the upper drive circuit board 10a having the highest temperature, the cooling can be efficiently performed. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to an induction heating cooker, and more particularly to a configuration for cooling an induction heating coil and a driving circuit board thereof.

  2. Description of the Related Art In recent years, induction heating cookers have become widespread as heating cookers used in kitchens as safe and clean heat sources that do not use fire and do not use combustion gas. The conventional configuration of this induction heating cooker is as follows.

  FIG. 4 is a perspective view of the induction cooking device attached to the cabinet. Generally, this type of induction heating cooker is used by being incorporated in a cabinet 100 of a system kitchen. A top plate 2 is provided on the upper surface of the outer case 1, and the top plate 2 is provided with two induction heating sections 3a and 3b, a single radiant heater 4, and an intake port 5. A roaster 6 for baking fish and the like and an operation unit 7 for operating the roaster and the heating unit are provided on the front side surface.

  FIG. 5 is a right side sectional view of the induction cooking device. In the figure, an induction heating coil 8 is provided below the top plate 2 corresponding to the induction heating unit 3a. A drive circuit 9 for driving the induction heating coil 8 is provided below the drive circuit board 10. A fan chamber surrounded by a fan case 11 and a fan cover 12 and having a fan 13 and a motor 14 for driving the fan 13 is provided near the drive circuit board 10. The fan 13 is generally an axial fan. Note that a partition plate 16 that controls the flow of wind and supports the drive circuit board 10 via a board base 15 is provided below the drive circuit board 10.

  In this configuration, when the motor 14 is driven and the fan 13 rotates, air is sucked in from the intake port 5. This air flows downward along the outer casing 1 as shown by the arrow, passes through the fan 13, and is exhausted from the exhaust port of the fan chamber toward the drive circuit board 10 and the induction heating coil 8. After cooling the components of the drive circuit 9 on the drive circuit board 10, the airflow further cools the induction heating coil and is discharged out of the outer case 1.

  Although the same configuration as that of the induction heating unit 3a is provided for the induction heating unit 3b, the description thereof is omitted.

  However, in recent years, there has been an increasing demand for increasing the inner volume of the roaster in order to improve its usability. Simply increasing the internal volume to meet this demand has caused a problem that the size of the induction heating cooker as a whole increases.

  Therefore, it has been conceived to design a drive circuit board having a drive circuit for driving the induction heating coils on the left and right sides by stacking the drive circuit board on one of them. However, in this case, if a conventional axial flow fan is used as it is to cool the stacked drive circuits, the flow rate is insufficient and the cooling cannot be performed sufficiently. Therefore, it was considered to increase the number of fans or increase the output. However, when used in a narrow space inside the outer casing of the induction heating cooker, sufficient intake cannot be obtained and the installation space is also insufficient. Also, if the capacity of the fan is increased, the noise becomes loud and a new noise becomes a problem. In addition, in the induction heating cooker, so-called overflow countermeasures, in which juice and water spilled on the top plate enter through the air inlet and adversely affect electric parts, have to be considered.

  The present invention is to solve the above-mentioned problem, and to provide a cooling structure that can obtain a sufficient amount of air for cooling the drive circuit with one fan even if the drive circuit boards are stacked on one side and solve the overflow problem. With the goal.

  In order to solve the conventional problem, the induction heating cooker of the present invention uses a centrifugal fan as a cooling fan for cooling the induction heating coil and the drive circuit. In addition, this centrifugal fan has intake ports on both the upper and lower sides, and is provided with a partition for separating intake air from above and below.

  With this configuration, the air intake volume can be greatly increased because air is taken in from above and below the centrifugal fan, and the partitioning portion prevents turbulence due to air intake from the upper and lower intake ports, and the partitioning portion with the largest exhaust volume is cooled most. Cooling efficiency can be increased by corresponding to the necessary parts.

  According to the first to sixth aspects of the present invention, the drive circuit can be sufficiently cooled even if the drive circuit boards are stacked in two stages.

  According to the seventh aspect of the present invention, the scattering of water due to overflow can be suppressed, and the reliability of the electric component can be improved.

  Further, according to the invention described in claim 8, the reliability of the induction heating coil or the drive circuit can be improved, and the cost of the induction heating coil can be reduced depending on the design.

  The invention described in claim 1 is a top plate provided on an upper surface of an outer case, a plurality of induction heating coils provided on a lower surface of the top plate, and induction provided corresponding to each of the plurality of induction heating coils. A power supply unit in which a plurality of drive circuit boards having a drive circuit for driving the heating coil are stacked in multiple stages, a centrifugal fan that blows the drive circuit board and the induction heating coil, and a motor that drives the centrifugal fan, The centrifugal fan includes a roaster, an operation unit for operating the induction heating coil and the roaster, and the centrifugal fan has intake ports at both upper and lower sides, and has a configuration having a partition unit that separates intake air from above and below. The intake volume can be greatly increased by taking in air from the top and bottom of the centrifugal fan, and the partition prevents turbulence caused by intake air from the upper and lower intake ports. It can be mentioned cooling efficiency can correspond to the most frequently required portion of the partition portion most cooling amounts.

  According to the second aspect of the present invention, since the motor for driving the centrifugal fan is provided above the centrifugal fan, the centrifugal fan is less susceptible to flooding. it can.

  The invention according to claim 3 is configured such that the position of the partition portion of the centrifugal fan is not lower than the position of the uppermost drive circuit board of the drive circuit boards stacked in multiple stages, so that the highest temperature is obtained. The drive circuit of the uppermost drive circuit board can be cooled well.

  According to a fourth aspect of the present invention, the pressure loss due to the motor provided on the upper portion of the centrifugal fan is reduced by adopting a configuration in which the amount of intake air from the upper intake port of the centrifugal fan is made smaller than the amount of intake air from the lower intake port. The influence can be reduced and the intake efficiency of the entire centrifugal fan can be increased.

  According to a fifth aspect of the present invention, the air flow from the lower intake port is increased by making the pressure loss of the air path to the upper intake port of the centrifugal fan larger than the pressure loss of the air path to the lower intake port. be able to.

  According to a sixth aspect of the present invention, the upper drive circuit board having a high temperature is provided by providing a partition so that the area of the upper exhaust port of the centrifugal fan is smaller than the area of the lower exhaust port. It can be cooled efficiently.

  The invention according to claim 7 is provided with a water retaining plate for temporarily storing overflow water in an air passage between the outer case and the fan case, and the water retaining plate gradually overflows between the outer case and the fan case. By providing a gap that allows water to leak into the power supply room, it is possible to stop the flow of water that has entered from the suction port and reduce the number of splashes, making it difficult for splashes to enter the power supply room and reducing damage to electrical components due to moisture. Can be.

  The invention according to claim 8, wherein a top plate provided on the upper surface of the outer case, an induction heating coil provided on the lower surface of the top plate, a drive circuit board having a drive circuit for driving the induction heating coil, A centrifugal fan that sends cooling air to the drive circuit is provided, and the centrifugal fan has intake ports on both the upper and lower sides, and has a configuration that has a partition part that separates intake air from above and below, so that the drive circuit can be sufficiently equipped. Cooling can be performed, and reliability can be improved. Further, the temperature rise of the induction heating coil can be suppressed, and depending on the design, the cost can be reduced by changing the insulating section of the winding from class H to class F or reducing the wire diameter of the winding. .

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  Note that components having the same functions as those of the conventional example are denoted by the same reference numerals, and description thereof is omitted. In addition, the external perspective view of the induction heating cooker used in the present invention is the same as the external perspective view described in the conventional example, and the description is omitted.

  FIG. 1 is a side sectional view of an induction heating cooker according to Embodiment 1 of the present invention. In the present embodiment, an induction heating cooker having a so-called two-port stove having two induction heating coils will be described.

  In FIG. 1, an induction heating coil 8 is attached to a lower portion of the top plate 2 corresponding to the induction heating section 3a shown in FIG. Drive circuit boards 10a and 10b having drive circuits 9a and 9b for driving the induction heating coils provided corresponding to the two induction heating coils by the power supply unit 19 are provided at the lower portion of the substrate base cover 18, respectively. 20a, 20b. A fan chamber 21 surrounded by a fan case 11 and a fan cover 12 is provided beside the power supply unit 19, and a centrifugal fan 22 and a motor 23 for driving the centrifugal fan 22 are provided therein. I have.

  In this embodiment, two induction heating coils are used, drive circuit boards provided with a drive circuit for driving one induction heating coil are provided, and two drive circuit boards are stacked and used. And The portion where the conventional drive circuit board and the cooling fan were provided has an expanded roaster portion to improve the usability of the roaster. In this configuration, the problem is how to cool the drive circuit portion of the drive circuit boards stacked in two stages. In the present embodiment, what needs cooling is the drive circuits 9a and 9b on the drive circuit boards 10a and 10b stacked in two stages with the induction heating coil 8. Therefore, the cooling air needs to cool the induction heating coil 8 and the two drive circuits 9a and 9b. By increasing the cooling air in the drive circuit 9a located above the two-stage stack, the air after the cooling of the drive circuit 9a can be effectively passed to the induction heating coil 8, and the cooling performance of the induction heating coil 8 can be improved. Can be improved.

  For this reason, in the present embodiment, a centrifugal fan that has a high air pressure and a large air volume and can control the exhaust air volume by the position of the exhaust port is used, and a sirocco fan is provided with a partition plate.

  Hereinafter, the configuration of the sirocco fan used in the present embodiment will be described.

  In FIG. 1, a sirocco fan 22, which is a centrifugal fan, has two intake ports, a lower intake port 24 and an upper intake port 25. For this reason, the intake area becomes large, and a large intake amount can be taken. Numeral 26 denotes a partition plate for preventing the intake air from above and the intake air from below from being mixed and causing turbulence. 27 is a lower exhaust port, and 28 is an upper exhaust port. The motor 23 for driving the sirocco fan 22 is provided for countermeasures against overflow, which will be described later, and may be provided below if sufficient countermeasures against overflow are taken. However, since the motor 23 also generates heat, it is preferable to provide the motor 23 above the motor 23 in order to reduce the thermal effect.

  FIG. 2 shows the air volume (displacement) characteristics of the sirocco fan 22 having such a configuration. FIG. 2 shows the relative difference in the amount of air discharged depending on the position of the partition plate 26. The horizontal axis indicates the discharge by the ratio (the area ratio between the lower exhaust port and the upper exhaust port) of the length C from the lower intake port 24 to the partition plate 26 and the length D from the partition plate 26 to the upper intake port 25. It shows the difference in the amount of air to be blown. As shown in the drawing, when the ratio of the length C is about 60 to 80% of the entire length (C + D), the amount of air discharged is the largest. This is because the motor 23 is located above the upper intake port 25, and the intake from above is obstructed. If the motor 23 is mounted below, the length C between the lower intake port 24 and the partition plate 26 becomes the entire length C. It is considered that the air volume becomes maximum when the partition plate 26 is provided at a position of 20 to 40% of the length.

  In addition, the air volume of each part of the sirocco fan 22 having the partition plate 26 is the smallest near the lower and upper intake ports 24 and 25, and the air volume increases as approaching the partition plate 26. Since there is an air volume exhausted from both, the air volume becomes the maximum in this area. Therefore, designing such that the position of the partition plate 26 is located at the position of the drive circuit 9a that requires the most cooling is a design that increases the cooling efficiency.

  Next, the intake air path will be described. After passing through the air passage 29, the cooling air sucked from the air inlet 5 of the induction heating cooker is divided into air passages 30 and 31 and reaches the lower air inlet 4 and the upper air inlet 5 of the sirocco fan 22.

  In the present embodiment, in order to obtain a large amount of air, the intake from the upper intake port is made smaller than the intake from the lower intake port. Specifically, the cross-sectional area A of the air passage 30 is larger than the cross-sectional area B of the air passage 31. As a result, the lower intake air amount can be increased, so that the amount of cooling air to the drive circuit 9a that is most necessary can be increased.

  In addition, the effect of the pressure loss of the motor 23 can be minimized by reducing the upward air flow.

  As described above, the sirocco fan 22 used in the present embodiment has the following features. (1) A motor is provided at the upper part as a measure against overflow, (2) Upper and lower intake ports are provided to increase the amount of intake, (3) Partition plate In addition to preventing turbulence of intake air from above and below, the air volume distribution at the exhaust port is increased, and the air volume especially near the partition plate is increased.

  Next, the flow of the cooling air will be described.

  As indicated by the arrows, the cooling air taken in from the inlet of the induction heating cooker passes through the air passages 29 and then passes through the air passages 30 and 31 to reach the inlets 24 and 25 of the sirocco fan 22. The cooling air discharged from the vicinity of the partition of the sirocco fan 22 and from the lower exhaust port 27 cools the drive circuits 9a and 9b, and then cools the induction heating coil 8 and another induction heating coil (not shown). Part of the cooling air discharged from the upper exhaust port 28 passes through the opening 32 and directly cools the induction heating coil 8 directly. Therefore, in order to improve the cooling property of the induction heating coil 8, it is necessary to increase the cooling air to the drive circuit 9a side, and the partition plate 26 is provided at the position of the drive circuit 9a for cooling. Although cooling is possible without the partition plate 26 at this position, the cooling efficiency is improved by doing so. Note that the exhaust volume distribution of the upper and lower exhaust ports can be easily changed by adjusting the position of the partition plate 26 and the upper and lower intake volumes, that is, by determining the size of the cross-sectional area of the air passages 30 and 31 by design.

  As described above, according to the present embodiment, the cooling fan and the drive circuit board conventionally provided for each induction heating coil corresponding to each induction heating coil are replaced with two stages of drive circuit boards on one induction heating coil side. The drive circuit and the induction heating coil can be sufficiently cooled even if they are arranged one on top of the other and the cooling fan is replaced with one centrifugal fan. Therefore, a space is provided between one of the cooling fans and the drive circuit board, and this portion can be used for expanding the inner volume of the roaster.

(Embodiment 2)
FIG. 3 is a sectional view of an induction heating cooker according to Embodiment 2 of the present invention.

  The second embodiment differs from the first embodiment in that the second embodiment has a countermeasure against overflow in the first embodiment. Therefore, the configuration of the induction heating cooker is the same as that of FIG. 1 except for the portion where the countermeasure against overflow is performed, and the description thereof is omitted.

  The problem of overflow in the induction heating cooker is that a user mistakenly turns a pot or the like at the time of cooking, so that broth or water (hereinafter referred to as water) spills on the top plate 2, which flows from the intake port 5 and hits the outer case 1. Splashes and splashes. The splash is sucked by the sirocco fan 22 and carried into the power supply unit 19, thereby damaging the drive circuit and other electric components on the drive circuit board.

  Hereinafter, flood countermeasures according to the present embodiment will be described with reference to FIG.

  In FIG. 3, the water retaining plate 33 enters from the intake port 5, and falls along the outer case 1 or directly and temporarily stops water, thereby reducing the momentum of the fall and preventing the water from being scattered. is there. The retaining plate 33 is provided with a through hole 34. This is to allow cooling air to pass, and the opening area is increased so that pressure loss hardly occurs. A narrow gap 35 is provided between the water retaining plate 33 and the outer case 1. This gap 35 gradually leaks the water stored in the water retaining plate 33, the water is stored in the water retaining plate 33, overflows the water retaining plate 33, falls through the through hole 34, and at this time, prevents the water from scattering again. It is aimed at.

  As described above, the water retaining plate 33 needs to stop the momentum of the water, reduce the amount of scattering and leak the retained water, and not to obstruct the passage of the cooling air. The configuration is not particularly limited as long as this condition is satisfied. That is, FIG. 3 shows a configuration in which the water retaining plate 33 is attached to the fan case 11 and the gap 35 is provided between the water retaining plate 33 and the outer case 1, but the present invention is not limited thereto. It may be attached to the outer case 1 so as to have a gap for water leakage, and the space between the fan case 11 and the water retaining plate 33 may be a space.

  Further, in the present embodiment, the skirt portion 36 is provided in a through-hole portion of the fan case 11 corresponding to the lower intake port 24 of the sirocco fan 22. This is to prevent the splash from hitting the hakama portion 36 and being sucked into the sirocco fan 22. However, if the length of the hakama becomes longer, the pressure loss becomes larger, so that it cannot be made too long. As described above, the amount of water sucked into the sirocco fan 22 can be significantly reduced by the overflow countermeasures of the present embodiment. Therefore, the reliability of the electric component can be greatly improved.

  In the first embodiment, the cooling in the case where two drive circuit boards of an induction heating cooker having a two-hole stove having two induction heating coils are stacked and used is described. However, the present invention is not limited to this. Absent. In particular, since the sirocco fan used in the first embodiment has upper and lower intake ports, the amount of intake air in a narrow space such as the inside of the outer case can be increased, and the exhaust air volume (cooling air volume) has a distribution. A portion with a large amount of exhaust air can be applied to the portion. Therefore, a large cooling effect can be obtained by using the sirocco fan described in the first embodiment even when one drive circuit board of a one-port stove or a drive circuit board of a two-port stove is separately cooled. it can. For this reason, the temperature rise of the drive circuit and the induction heating coil can be suppressed, and the reliability can be improved. Further, the temperature rise of the induction heating coil can be suppressed, and depending on the design, the cost can be reduced by changing the insulating section of the winding from class H to class F or reducing the wire diameter of the winding.

  Further, even when a sirocco fan is provided corresponding to one drive circuit board, the motor for driving the sirocco fan described in the first embodiment is provided at the upper part of the sirocco fan. Reduce the air intake pressure from the intake port, make the pressure loss of the air path to the upper intake port of the sirocco fan larger than the air path pressure loss to the lower intake port, or make the area of the upper exhaust port of the sirocco fan lower. By providing a configuration such as providing a partition so as to be smaller than the area of the exhaust port, the cooling efficiency can be further improved. Further, as described in the second embodiment, a water flow plate for temporarily storing overflow water is provided in an air passage between the outer case and the fan case, and the overflow water stored between the water plate and the outer case gradually decreases. By providing a gap so as to be intoxicated or by providing a collar in the air passage corresponding to the lower intake port of the centrifugal fan of the fan case, it is possible to achieve the same flood countermeasures as in the second embodiment. Needless to say.

  INDUSTRIAL APPLICABILITY As described above, the induction heating cooker according to the present invention can be applied to applications in which the cooling efficiency of the induction heating coil and the drive circuit board thereof is increased, and the reliability of the electric components is increased with respect to overflow from the intake port. Can be.

Side sectional view of the induction heating cooker according to Embodiment 1 of the present invention. The figure which shows the relationship between the partition plate position of the sirocco fan of the said induction heating cooker, and exhaust air volume Side sectional view of the induction heating cooker according to the second embodiment of the present invention. Appearance perspective view of induction heating cooker Side sectional view of a conventional induction heating cooker

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Outer case 2 Top plate 5 Inlet 6 Roaster 7 Operation part 8 Induction heating part 9a, 9b Drive circuit 10a, 10b Drive circuit board 19 Power supply part 22 Sirocco fan (centrifugal fan)
Reference Signs List 23 Motor 24 Lower intake port 25 Upper intake port 26 Partition plate 27 Lower exhaust port 28 Upper exhaust port 30 Air path 33 Water retaining plate 35 Gap 36 Hakama section

Claims (8)

It has a top plate provided on the upper surface of the outer case, a plurality of induction heating coils provided on the lower surface of the top plate, and a drive circuit for driving the induction heating coils provided corresponding to each of the plurality of induction heating coils. A power supply unit in which a plurality of drive circuit boards are stacked in multiple stages, a centrifugal fan for blowing air to the drive circuit board and the induction heating coil, a motor for driving the centrifugal fan, a roaster, the induction heating coil, and An operation unit for operating a roaster, wherein the centrifugal fan has intake ports on both the upper and lower sides and has a partition unit for separating intake air from above and below. The induction heating cooker according to claim 1, wherein a motor that drives the centrifugal fan is provided above the centrifugal fan. 3. The induction heating cooker according to claim 1, wherein the position of the partition portion of the centrifugal fan is not lower than the position of the uppermost drive circuit board of the drive circuit boards stacked in multiple stages. The induction heating cooker according to any one of claims 1 to 3, wherein an amount of intake air from an upper intake port of the centrifugal fan is smaller than an amount of intake air from a lower intake port. 5. The induction heating cooker according to claim 4, wherein a pressure loss of an air path to an upper intake port of the centrifugal fan is made larger than a pressure loss of an air path to a lower intake port. The induction heating cooker according to any one of claims 1 to 5, wherein a partition portion is provided such that an area of an upper exhaust port of the centrifugal fan is smaller than an area of a lower exhaust port. A water retaining plate for temporarily storing overflow water is provided in an air passage between the outer case and the fan case, and the water retaining plate is provided with a gap between the outer case and the overflow case so that the overflow gradually leaks. The induction heating cooker according to any one of claims 1 to 6, having a configuration. A top plate provided on the upper surface of the outer case, an induction heating coil provided on the lower surface of the top plate, a drive circuit board having a drive circuit for driving the induction heating coil, and a centrifugal blower for blowing cooling air to the drive circuit And a centrifugal fan, wherein the centrifugal fan has intake ports on both the upper and lower sides, and has a partition portion for dividing intake air from above and below.

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