JPH027382A - Cooker - Google Patents

Abstract

PURPOSE:To achieve smallness of a heat sink, smallness and low rotation of an air blowing fan, by linking a thick part for parts attachment and a thick part to which wings are provided in both the upper and the lower directions at a thick part. CONSTITUTION:A heat sink 5 has a thick part for parts attachment and a thick part 15 located at a higher position with wings 16, 17 provided in both the upper and in the lower directions, and the thick part 14 for parts attachment and the thick part 15 to which wings are provided in both the upper and the lower directions are linked at a thick part 18. Hence, the flow of air through rotation of an air blowing fan can be blown effectively to a heat sink. Thereby, cooling ability can be improved with heat exchange efficiency being raised, and smallness and lightness of a heat sink, smallness and low rotation of an air blowing fan, smallness of a motor, reduction in piling thicknesses of a coil and a core can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cooking appliance such as a rice cooker that is used in general households and utilizes an induction heating source.

2. Description of the Related Art Conventionally, cooking appliances using an induction heating source are known, for example, as having the following structure.

That is, in FIGS. 4 and 6, 101 is a stand on which cooking items such as pots are placed, 102 is a lower frame that holds the stand 101, 103 is an induction coil that is an induction heating source, and 104 is a stand that holds the induction coil 103. A cover, 105 is a substrate of an inverter circuit that excites the induction coil 103, 106 is a semiconductor switch element which is a component of the inverter circuit, 107 is a heat sink attached to the lower frame 102, and the upper surface of this heat sink 107 has a circuit board for the inverter circuit that excites the induction coil 103. Semiconductor switch element 10 that self-heats by switching the current of
6 is installed and performs cooling. 108 is a motor, 109 is a blower fan which is pivotally supported by the motor 108 and blows air, 110 is an intake hole, and 111 is an exhaust hole.

Problems to be Solved by the Invention In the conventional cooking appliance described above, the heat sink 107 is located in a position facing the blower fan 109 laterally, the semiconductor switch element 106 is attached to the upper surface of the heat sink 107, and the heat sink 107 is attached to the lower frame 102. It is fixed on the entire surface, and the thick part for mounting the semiconductor switch element 106 is flat, and the length of the downward blade 107a of the heat sink 107 is particularly short, so the direction and flow of the air blown by the ventilation fan 109 is effective. Therefore, the semiconductor switch element 10 that does not act on the heat sink 107 and that is most desired to be cooled
The heat sink 10 with which No. 6 was installed could not provide sufficient cooling.

In this configuration, in order to sufficiently cool the heat sink 107, it is necessary to increase the surface area of the heat sink 107 and increase the amount of air blown. Moreover, there was no choice but to make the product heavier, which resulted in problems in that the cost increased and the product became heavier.

In order to increase the amount of air blown, the diameter and height of the fan 109 are increased, and the number of revolutions is also increased to increase the rotational torque. As a result, there were problems in that the cost increased significantly, the product shape became larger, and the noise was higher.

The present invention solves the above-mentioned problems, and aims to improve the cooling of the inverter circuit components attached to the heat sink, and to provide a cooking device in which the heat sink can be made smaller, the blower fan can be made smaller, and the rotation speed can be lowered. This is the purpose.

Means for Solving the Problems In order to solve the above problems, the cooker of the present invention includes an inverter circuit that excites an induction coil, a heat sink in which components of the inverter circuit are attached to the lower surface of the thick part, and the heat sink. The heat sink includes a blower fan disposed at the bottom of the heat sink, and a motor that rotationally drives the blower fan, and the heat sink has a thick wall portion for mounting the component, and a thick wall portion having blades in both the upper and lower directions at positions υ higher than the thick wall portion. The thick part for attaching parts and the thick part provided with blades in both the upper and lower directions are connected by the thick part.

According to the above configuration, air is sucked in from the intake hole of the intake section by the rotation of the blower fan driven by the motor at multiple rotations, and this sucked air is sent from the blower fan to the heat sink via the motor. The direction of the wind flowing on the top surface, the direction of the wind hitting the side of the heat sink placed on the top of the fan and cooling this side and flowing to the top surface of the heat sink, and the direction of the wind hitting the bottom surface of the heat sink and flowing along this bottom surface. In this case, the thick part of the heat 7 tank for attaching parts has the highest temperature, and since that part is close to the blower fan, it is cooled by direct blowing air from the blower fan.

Furthermore, heat is conducted from the thick wall part for attaching parts to the thick joint wall part and then to the thick wall part with blades in both the upper and lower directions. Since it efficiently hits the upper and lower blades of the thick walled portion in both directions, cooling progresses even further.

In this way, the airflow generated by the rotation of the fan is blown to the heat sink without waste, so this action allows the heat sink to be made smaller, the blower fan to be smaller, and the rotation speed to be lowered. , it is possible to reduce costs, make the product more compact, lightweight, and reduce noise.

EXAMPLE Hereinafter, an example of the present invention will be described based on the accompanying drawings.

In FIGS. 1 to 3, reference numeral 1 denotes an induction coil which is an induction heating source, and this induction coil 1 is held by a lip of a cover 2. Reference numeral 3 denotes an inverter circuit that excites the induction coil 1, and above the inverter circuit 3, a semiconductor switch element 4, which is a component of the inverter circuit 3, is provided. 6
is a semiconductor switch element 4 that generates heat due to switching loss, etc.
The heat sink 6 is attached with screws 5a, and the heat sink 6 and the cover 2 are held on the lower frame 6 by screwing or the like. 7 is a motor attached to the lower frame 6 with a metal fitting,
The intake side of a propeller-type blower fan 8 that is rotatably supported by the motor 7 is surrounded by an intake cover 9 .

10 is an intake hole provided in the intake cover 9, and this intake hole 1o
External air is sucked in by the rotation of the ventilation fan 8. Reference numeral 11 denotes a guide surrounding the exhaust side of the blower fan 8. Reference numeral 12 denotes the lower portion of the protective frame that holds the induction coil 1 and faces the rice cooker 21 that is heated. 13 is an exhaust hole provided in the lower frame 6. 14 is a thick part of the heat sink 5 for attaching parts; 16 is a thick part provided at a higher position than the thick part 14 of the heat sink 5; this thick part 16 has a downward wing 16 and an upward wing 17; Equipped with: Reference numeral 18 denotes a connecting thick part that thermally and structurally connects the thick part 14 for attaching parts to the thick part 15 provided with blades 16 and 17 in both the upper and lower directions.

In the cooker with the above configuration, the semiconductor switching element 4 that switches the current to the induction coil 1 has a heat loss of 30 to 50 W due to switching loss, on-loss, etc., so a configuration for reducing the temperature rise will be described below. do. That is, by the rotation of the blower fan 8 that is pivotally supported by the motor 7, external air is sucked in through the intake hole 1o provided in the intake cover 9. The sucked air then flows from the blower fan 8 through the motor 7 to the top surface of the heat sink 6, hits the side surface of the heat sink 5 placed above the blower fan 8, cools this side surface, and flows to the top surface of the heat sink 5. The direction of the wind is also the direction of the wind that hits the bottom surface of the heat sink 5 and flows along this bottom surface.
In this case, the thick part 14 of the heat sink for attaching parts has the highest temperature, and since that part is close to the blower fan 8, the air from the blower fan 8 directly hits it and cools it. Furthermore, the heat is transferred from the thick part 14 for attaching parts to the joint thick part 1.
8 and is transmitted both upward and downward to the thick walled part 16 equipped with blades 16 and 17. However, the flow of air to the upper and lower surfaces of the heat sink 6 by the blower fan 8 is caused by the blades 16 and 17 both upward and downward.
6.17, the upper blade 17 and the lower blade 16 of the thick walled portion 16 are efficiently hit, so that cooling further progresses.

In this way, the air flow due to the rotation of the fan 8 is blown to the heat sink 5 without waste.

Due to this effect, it is possible to make the heat sink 5 smaller, the blower fan 8 smaller, and the rotation speed lower, so that the stacked thickness of the windings and core of the motor 7 can be reduced, and costs can be reduced. At the same time, the product can be made more compact, lighter, and less noisy.

In addition, the thick wall portion 1 is provided with blades 16 and 17 in both the upper and lower directions.
5 on both sides of the thick part 14 for attaching parts, heat conduction improves heat dispersion with the semiconductor switch element 4 in the center, and air flow is directed to the upper and lower blades 16 .
Since heat can be efficiently converted at 17, cooling is increased. With this configuration, it is possible to obtain the effect of reducing the temperature rise of the semiconductor switching element 4 by about 3 days.

Furthermore, by providing the joint thick portion 18 at an angle, one more upwardly facing blade 17 is added to the inclined portion, so the surface area of the heat sink 6 increases and the temperature of the semiconductor switch element 4 increases. This has the effect of reducing the amount by about 1 day.

Furthermore, the thick part 16 is provided with blades 16.17 in both the up and down directions at a position where the lengths of the upward blades 17 and the downward blades 16 of the thick part 15 are approximately the same. By providing the upper and lower blades 16.
Since the degree of cooling and heat conduction from the thick portion 17 to the thick portion 16 are made uniform, the cooling effect is increased by the amount that the heat conduction is improved.As a result, the temperature rise of the semiconductor switch element 4 is reduced by about 1 day. This has the effect of reducing the

In addition, blades 1 are provided on the heat sink close to the side surface of the lower frame 6 to which the heat sink 6 is attached, and are provided with blades 1 in both the upper and lower directions.
By providing the radial vanes 19 at the end of the thick walled portion 15 having a diameter of 6.17, the air flows smoothly along the side surface of the lower frame 6. The cooling effect is improved by the radial blades 19 that increase the area of the heat sink 6 in the portion along the radial direction, thereby reducing the temperature rise of the semiconductor switch element 4 by about 1 day.

Further, a gap is provided between the tip 20 of the downward facing blade 16 of the heat sink 5 and the surface of the lower frame 6 that this tip 20 faces, and furthermore, a gap is provided between the tip 20 of the downward facing blade 16 of the heat sink 5.
By providing a gap between the surface of the board 3a of the inverter circuit 3 and the surface of the board 3a of the inverter circuit 3, the air from the blower fan 8 hits the bottom surface of the heat sink 5, and the air flow is directed toward the tips of the downward blades 16. 2o and the surface of the lower frame 6 and the gap between the surface of the substrate 3a of the inverter circuit 3, the temperature rise of the semiconductor switch element 4 can be reduced by about 2 days. It is something.

At this time, it is effective that the gap is 2 to 8n, and the larger the number of blades provided with the gap, the more effective it is.
The length of the downward facing blade 16 in 5 is determined by lengthening the side surface of the lower frame 6 to which the heat sink 6 is attached, so that the air flows along the side surface of the lower frame 6, and the area of the blade in that part is increased. As a result, the cooling performance is improved, and as a result, the temperature rise of the semiconductor switch element 4 is reduced by about 1 dep.
This has the effect of reducing the

By combining the above-mentioned configurations, the heat sink 6 can be further miniaturized, and the blower fan 8 can also be further miniaturized and rotate at a lower speed, resulting in significant cost reductions and a more compact and low-cost product. This can be used to reduce noise.

Effects of the Invention As is clear from the description of the embodiments above, the cooking appliance of the present invention includes an inverter circuit that excites an induction coil, a heat sink in which parts of the inverter circuit are attached to the lower surface of the thick part, and a lower part of the heat sink. A blower fan placed in the
The heat sink has a thick wall portion for mounting the component, and a thick wall portion having blades in both vertical directions at a higher position, and a motor for rotating the blower fan. Since the thick part and the thick part with blades in both the upper and lower directions are connected by the thick part, the air flow generated by the rotation of the blower fan can be blown to the heat sink without waste. It is possible to improve cooling performance by increasing heat exchange efficiency. Due to this effect, it is possible to make the heat sink smaller and lighter, the blower fan smaller and have lower rotation speed, the motor smaller, and the stacked thickness of the windings and core reduced.As a result, the cost is reduced. This makes it possible to make products more compact, lighter, and less noisy.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a cooking device showing an embodiment of the present invention;
Fig. 2 is a sectional view taken along the line A-A in Fig. 1, Fig. 3 is a sectional view showing the entire cooker, Fig. 4 is a sectional view of the conventional cooker, and Fig. 6 is the same. It is a partial sectional view of a cooking appliance. 1...Induction coil, 2...River/cover, 3...
... Inverter circuit, 4 ... Semiconductor switch element, 5 ... Heat sink, 6 ...
Lower frame, 7...motor, 8...fan,
14... Thick part for mounting parts, 15...
・Thick part, 16...Downward blade, 17...Curved upward blade, 8...Connected thick part.

Claims (8)

[Claims] (1) An inverter circuit that excites an induction coil, a heat sink with the parts of this inverter circuit attached to the bottom surface of the thick part, a blower fan placed at the bottom of this heat sink, and a motor that rotationally drives this blower fan. Prepare,
The heat sink has a thick part for attaching the component, and a thick part having blades in both the upper and lower directions at a higher position than the thick part for attaching the component, and a thick part having the thick part for attaching the component and the blade in both the upper and lower directions. A cooking utensil made by connecting thick parts with thick parts. (2) The cooking appliance according to claim 1, wherein the thick wall portion provided with blades in both the upper and lower directions is arranged on both sides of the thick wall portion for attaching parts. (3) The cooking appliance according to claim 1, wherein the thick wall portion that connects the thick wall portion having the blades in both the upper and lower directions and the thick wall portion for attaching parts is provided in an inclined manner. (4) The cooking device according to claim 1, wherein the position of the thick wall portion having the blades in both the upper and lower directions is substantially the same as the length of the upper and lower blades. (5) Claim 1, in which the blades are provided radially at the end of the thick part that is provided on the heat sink close to the side surface of the lower frame to which the heat sink is attached, and is provided with blades in both the upper and lower directions. cooker. (6) The cooking appliance according to claim 1, wherein a gap is provided between the tips of the downward blades of the heat sink and the lower frame to which the heat sink is attached. (7) The cooking appliance according to claim 1, wherein a gap is provided between the tips of the downward blades of the heat sink and the board of the inverter circuit to which the heat sink is attached. (8) The cooking appliance according to claim 2, wherein the length of the downwardly directed blades of the thick walled portion, which is provided with blades in both the upper and lower directions, is longer on the side surface of the lower frame to which the heat sink is attached.