BACKGROUND ART In general, an electrical cooker is an apparatus for performing cooking, using electricity as a heating source, and for rapidly cooking food by maintaining the inside of an oven at high pressure by making a heating temperature higher than that under normal pressure.

Figure 1 is a sectional view of an electrical cooker according to the conventional art.

As shown therein, a conventional electrical cooker includes a main body 102 in which an oven 104 is mounted, and a lid 108 connected with a hinge portion 106 at an upper part of the main body 102, and opening/closing the main body 102 by rotating centering on the hinge portion 106.

In the main body 102, an electrical heating apparatus 110 for heating the oven 104 is provided. The electrical heating apparatus 110 includes a working coil generating an induced current in cooking, a heater generating relatively small heat in keeping cooked food warm, and a heating vessel 112

at which the oven 104 is inserted.

According to the electrical cooker above, the oven 104 is heated by the electrical heating apparatus 110 thereby performing cooking. Since, during a cooking process, an inner portion of the lid 108 is adhered to an upper end of the oven 104, and a steam discharging valve maintains a closed state thereof, when steam is generated in boiling water, pressure in the oven 104 becomes greater than normal pressure.

As pressure gets greater, a temperature of water gets higher than the boiling points (100 degrees) under normal pressure, so that food is cooked quickly. When the cooking process is terminated, a steaming process of maintaining pressure in the oven 104 in a state that heating performed by the electrical heating apparatus 110 has been stopped, progresses for a certain time. After the steaming process has been terminated, a constant warming process progresses, which is that the oven 104 is weakly heated at a certain temperature by the electrical heating apparatus 110 in a state that steam in the oven 104 has been discharged to the outside and thus pressure in the oven 104 has been lowered.

At a front surface of the main body 102, a display window 114 for displaying an operational state and the like of the electrical cooker is provided, and, at the inside of the display window 114, a display PCB 116 having an LCD 118 or the like is mounted. At a rear portion of the display PCB 116, a power PCD 120 for controlling operations of the display PCB 116 and the electrical heating apparatus 110 is mounted. Also, at the bottom surface of

the main body 102, a cooling fan 126 for protecting the power PCB 120 from a high temperature the electrical heating apparatus 110 generates, is provided.

Herein, Figures 2 and 3 are a side view and a back view showing the power PCB 120 respectively. In the power PCB 120, various devices 130, 132 and 134 including a semiconductor device are provided on a substrate 128 to control various apparatuses.

Since these various devices 130,132 and 134 are high temperature heat generating devices, there is a need for cooling these devices to be operated normally. According to this, a cooling pin 124, what is called a heat sink, is attached at a main heat generating device 134 in order to cool the device with an enlarging cooling area.

Herein, the cooling pin 124 has a structure that a plurality of sheets with a plate form is collocated at certain interval therebetween, enlarges heat-transmitted area and cools heat generated at the heat generating device 134, performing heat-exchange with air flowed by the cooling fan 126 However, in the conventional electrical cooker constructed as above, the display unit for indicating a state of the cooker to a user is installed at the front portion of the main body 102. In case that the display unit is installed at the lid 108 in order that the user can easily check the display unit with the naked eye, since the power PCB 120 is provided at the front surface of the main body 102, an electric wire for connecting the display PCB 116 and the power PCB 120 has to be connected to the display PCB 116 from the front portion of the main body 10 via the rear of the main body 102 and the hinge

portion 106. Accordingly, the length of the electric wire is lengthened, and inside wiring is not easy.

Also, in the conventional electrical cooker, in order to sufficiently cool a heat generating device 34, a main heat generating source, a cooling area of the cooling pin 124 has to be large. Also, in order to make outside air flowed in the case through the cooling fan 126 concentrated toward the cooling pin 124, the cooling fan 126 has to be installed right under the cooling pin 124.

However, in case that the cooling fan 126 is installed right under the cooling pin 124, a certain distance between the cooling fan 126 and the cooling pin 124 has to exist in a vertical direction, and thus a whole height of the cooker becomes higher.

Also, in case that the cooling fan 126 is not installed right under the cooling pin 124, since a special apparatus for making an outside air, which is flowed in the case through the cooling fan 126, concentrated toward the cooling pin 124 is not provided, sufficient cooling efficiency for the heat generating source can not be obtained.

Also, since the cooling pin 124 can have sufficient cooling capability when a surface area coming in contact with air is large, the whole volume of the cooling pin 124 becomes greater as much, and so the cooling pin 124 greatly occupies an inner space of the cooker. Accordingly, a plan and a disposition for the inside of the cooker are not easy, and since the cooling pin 124 has a limit to increasing heat-exchange efficiency, it is not suitable for a device generating high temperature heat.

DISCLOSURE OF THE INVENTION Therefore, it is an object of the present invention to provide a cooling apparatus for an electrical cooker capable of reducing the whole height of a main body as well as making a wiring work between a display unit and a power PCB easy, by positioning a power PCB at the rear portion of a main body, and positioning a cooling fan near the front of the power PCB, in case that the display unit is installed at a lid.

It is another object of the present invention to provide a cooiihg apparatus for an electrical cooker capable of being assembled and produced easily, by simplifying its whole structure as well as improving cooling efficiency for a heat generating source by forming a guide structure at one portion of a tripod so as to concentratedly cool a heat generating device of the power PCB, and integrally installing a cooling fan at the guide.

It is another object of the present invention to provide a cooling apparatus for an electrical cooker capable of making parts mounted in the cooker easily planned and disposed, and reducing production expenses of a product, by improving cooling capacity with respect to a heat transmitting area by reforming a structure of a cooling pin, and so being able to reducing a volume of the cooling apparatus.

To achieve the above object, there is provided a cooling apparatus for an electrical cooker including a case receiving an oven therein, and having an inlet and an outlet at its bottom surface; a power PCB positioned at the rear

portion of the inside of the case; a cooling plate attached to a heat generating device of the power PCB; a cooling fan installed at an inlet of the case, and sucking outer air; and a support means supporting an oven in the case, and inducing air sucked through the cooling fan toward the cooling plate.

An outlet is formed at a rear surface of the case where the power PCB is mounted, and the inlet is formed at a rear portion of the bottom surface, and the outlet is formed at a front portion of the bottom surface.

At the cooling plate, a turbulator for guiding air flowed by the cooling fan so that the air can be concentrated at a portion of the cooling plate, which is adhered to the heat generating device, while passing over the turbulator, is installed.

The support means includes a support portion for supporting an oven in the case; and a guide portion integrally extended from the support portion, and guiding air flowed in the case through the cooling fan toward the cooling plate.

In a cooling apparatus for an electrical cooker according to the present invention, at the inside of the case, a support plate having a plurality of air passing holes is installed ; the support means includes a support portion for supporting an oven in the case, and a guide portion integrally extended from the support portion, and guiding air flowed in the case through the cooling fan toward the cooling plate ; and thus air sucked through the inlet is discharged to an outlet of the case via the cooling fan, the guide portion, the cooling plate, a back air passing hole of a support plate, and a front air passing hole of the

support plate.

A cooling apparatus for an electrical cooker includes a case receiving an oven therein, and having an inlet and an outlet at its bottom surface respectively; a power PCB positioned at the rear portion of inside of the case; a heat sink attached to a heat generating device of the power PCB; a cooling fan installed at the inlet of the case and at a position having a certain distance from a lower end portion of the power PCB 34 in a horizontal direction, and sucking outer air; and a support means for supporting an oven installed in the case.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a longitudinal sectional view showing an inner structure of an electrical cooker according to the conventional art; Figure 2 is a side view showing a cooling structure of a cooling apparatus according to the conventional art; Figure 3 is a front view showing a cooling structure of a cooling apparatus according to the conventional art; Figure 4 is a longitudinal sectional view showing an electrical cooker having a cooling apparatus according to the present invention; Figure 5 is a bottom view showing a bottom plate of an electrical cooker according to the present invention; Figure 6 is a back view showing a cooling structure of a power PCB of an electrical cooker according to the present invention;

Figure 7 is a side view showing a cooling structure of a power PCB of an electrical cooker according to one embodiment of the present invention; Figure 8 is a front view showing a cooling structure of a power PCB of an electrical cooker according to one embodiment of the present invention; Figure 9 is a perspective view showing a support apparatus of an electrical cooker according to the present invention; Figure 10 is a side view showing a PCB cooling structure of an electrical cooker according to another embodiment of the present invention; and Figure 11 is a front view showing a PCB cooling structure of an electrical cooker according to another embodiment of the present invention.

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a cooling apparatus for an electrical cooker according to the present invention will now be described with reference to accompanying drawings.

There can be a plurality of embodiments of a cooling apparatus for an electrical cooker according to the present invention, and hereinafter a preferred embodiment will be described.

Figure 4 is a longitudinal sectional view showing an electrical cooker having a cooling apparatus according to the present invention, and Figure 5 is a bottom view of an electrical cooker according to the present invention.

An electrical cooker according to the present invention includes a main

body 2 in which an oven 4 is mounted, an electrical heating apparatus 5 installed at a lower portion of the main body 2 to heat the oven 4, and a lid 8 connected to an upper portion of the main body by a hinge portion 6, and opening/closing the main body 2 by rotating centering on the hinge portion 6.

At the lid 8, a display unit 14 is provided so that a user can easily check a state of a cooker and also operate the cooker. The display unit 14 includes a display window 16 installed at the lid 8 and a display PCB 18.

The main body 2 includes a case 22 including a bottom plate 20 so as to form an enclosure of the cooker. At the bottom plate 20 of the case, an inlet 25 and a first outlet 26 are formed respectively so that outer air can be sucked and then discharged. Also, at the rear side of the case 22, a second outlet 28 is formed so that inner air can be discharged to the outside of case.

Herein, as shown in Figure 6, the inlet 24 is formed at a relatively rear portion of the bottom plate 20, and the first outlet 26 is formed at both sides of the front portion of the bottom plate 20. To be sure, preferably, the inlet 24 and the outlet 26 have a screen structure so that alien substances and the like are not flowed into the case 22.

The electrical heating apparatus 5 includes a working coil 10 generating an induced current in cooking, a heater generating relatively small heat in keeping cooked food warm, and a heating vessel 12. Herein, at the outside of the heating vessel 12, the working coil 10 is installed, and at the inside thereof, the oven 4 is inserted.

In order to support the heating vessel 12 in which the oven 4 is

inserted, a support apparatus is provided. The support apparatus includes a support plate 30 installed between a circumference of the heating vessel 12 and an inner surface of the case 22, and a tripod type support body 70 fixed to the support plate 30 by a coupling means such as a screw or the like, and supporting a lower portion of the heating vessel 12.

The support plate 30 has a plurality of air passing hole 32 so that air flowed in the case through the inlet 24 passes through an upper space of the main body, and then can be discharged to the outside through the outlet 26.

At the rear portion of the case 22, a power PCB 34 is vertically erected and fixed so as to control the cooker by being connected to the display PCB 14 and the working coil 10 and the like by an electric wire 40.

In order to cool the power PCB 34 with an air cooling method, a cooling fan is provided at the inside of the inlet 24 and at a position having a certain distance from a lower end portion of the power PCB 34 in a horizontal direction so as to forcedly suck outer air.

Figure 7 is a side view of a power PCB according to one embodiment of the present invention, and Figure 8 is a front view according to one embodiment of the present invention.

The power PCB 34 includes a substrate 46 mounted at a rear side of the case 22 by support brackets 36 and 38, and various devices 47,48 and 49 including a semiconductor device, mounted on the substrate 46 and controlling various apparatuses.

Herein, the various devices 47,48 and 49 are heat generating devices

generating high temperature heat during operation, and so in order that the semiconductor and the like can be operated normally, a cooling plate 50 and a turbulator 52 are provided.

Herein, the cooling plate 50 is adhered and fixed to the heat generating devices 49 of the power PCB 34, and expands a cooling area. The turbulator 52 is mounted at the cooling plate 50, and guides air flowed by the cooling fan 42 so that, going over the turbulator 52, the air can be concentrated at a portion of the cooling plate 50 which is adhered to the heat generating device 49.

To be sure, both cooling plate 50 and turbulator 52 are made of a metal material having great heat conductibility, and the cooling plate 50 has a single plate structure having a certain thickness.

In the cooling plate 50 above, the back of its one side end portion is adhered and fixed to the heat generating device, and at the front of its other side end portion, the turbulator 52 is installed. Thusly, the cooling plate 50 has a clank structure.

The turbulator 52 has a protrusion form protruded from the surface of the cooling plate 50. In the present embodiment, three turbulators collocated at a predetermined interval therebetween are illustrated, however, the number of turbulators may be one, two or even more than four.

In the embodiment of the present invention, it is illustrated that the turbulator 52 has a hexahedron type block structure, however, the structure of the turbulator can be variously varied according to operation conditions or

plan conditions.

That is, the front part of the turbulator 52 may be formed in a curved surface form in an air flowing direction so that flow resistance can be reduced, or at the rear part of the turbulator 52, a guide may be extended long up to the part where air has to be concentrated.

The cooling fan 42 is integrally fixed and installed at the tripod type support body 70. At this time, the cooling fan 42 is positioned at a lower portion of the heating vessel 12, and the power PCB 34 is positioned at the rear of a side surface of the heating vessel 12.

Herein, as shown in Figure 9, three feet 72,74 and 76 of the support body 70 are disposed in a radial form so as to support the heating vessel. At one 76 of the three feet, the cooling fan 42 is mounted, and the foot 76 guides air flowed by the cooling fan 42 so that the air can be concentrated at the side surface of the heating vessel 12 and thus be introduced toward the heat generating device 49.

That is, the support body 70 is provided with two support feet 72 and 74 for supporting the heating vessel 12 in the case 22, and a guide foot 76 integrally connected to the support feet 72 and 74, supporting the heating vessel with the support feet, and guiding air flowed in the case through the cooling fan 42 toward the cooling plate 50.

At an end of each foot 72,74 and 76 of the support body 70, a flange portion 78 is formed so as to fix the tripod to the support plate 30 by a screw or the like.

The guide foot 76 includes a fan-mounted portion 80 having a four- cornered box form so that the cooling fan 42 can be integrally installed, and a guide portion 82 extended upwardly from the fan-mounted portion 80 along the heating vessel 12, And, the width of the guide foot 76 is relatively greater than those of the two support foot 74 and 76.

At the tripod type support body 70, the cooling fan 42 is mounted, and one of the feet of the support body 70 becomes a guide foot 76 for making air flowed by the cooling fan 42 concentrated toward the cooling plate 50. For this reason, an installation structure of the cooling fan 42 is simplified, and, without installing a special air guiding fabrication, air can be concentrated toward the cooling plate 50 as well. Accordingly, cooling efficiency for the power PCB 34 including the heat generating device 49 can improved.

Also, the cooling fan 42 is not disposed right under the power PCB 34 and the cooling plate 50, but is disposed at the lower side of the heating vessel. For this reason, without extending the whole height of the cooker, the sizes of the power PCB 34 and the cooling plate 50 can be sufficiently enlarged according to the plan condition.

Operations of the cooling apparatus for an electrical cooker according to the present invention constructed as above will now be described.

When the cooling fan 42 is operated, outer air is flowed into the case 22 through an inlet 24 of a bottom plate 20. The flowed air passes through the cooling fan 42 and then flows toward the cooling plate 50 and the power PCB 34 by guiding of the guide foot 76 of the support body 70. During this flow,

heat-exchange of the air and the cooling plate 50 is occurred and thus the power PCB 34 and the heat generating device 49 are cooled.

At this time, a part of the air flowing toward the cooling plate 50 goes over the turbulator 52 with colliding against the turbulator 52, and then is concentrated to a portion of the cooling plate 50, which is adhered to the heat generating device 49.

Accordingly, since cooling air is concentrated at the portion adhered to the heat generating device 49 and so having a relatively higher temperature than at the other portions, heat transmission efficiency becomes higher at the high temperature portion, and thus the heat generating device 49 is effectively cooled.

A part of air which has performed a cooling operation is discharged to the outside through a second outlet 28 positioned at the rear of the power PCB 34. Remaining air flows to an upper space of the main body 2 through a back air passing hole 32 of the support plate 30, then flows to a lower space of the main body 2 through a front air passing hole 32 of the support plate 30, and then is discharged to a lower portion of both sides of the cooker through first outlets 26.

Figure 10 is a side view and also a detail drawing showing a heat generating device cooling structure according to another embodiment of the present invention, and Figure 11 is a front view showing a heat generating device cooling structure according to another embodiment of the present invention. Various devices 93,94 and 95 installed at a substrate 92 of the

power PCB 90 are heat generating devices generating high temperature heat during operation. So, a porous cooling plate 96, a cooling means is provided in order that a semiconductor device, which is a heat generating device, and the like can be normally operated.

The porous cooling plate 96 is made of a porous metal material, and is adhered to the heat generating device 95, and cools heat generated from the heat generating device 95.

Herein, the porous cooling plate 96 has a plurality of holes so that heat-exchange can be performed while air forcedly flowed by the cooling fan 42 passes through the holes. That is, preferably, the porous cooling plate 96 is formed by zigzag and consecutively attaching a wire to the substrate 92 with a predetermined space between the wires.

Operations of a heat generating device cooling apparatus of the cooker according to another embodiment of the present invention constructed as above will now be described.

When the cooker is operated, an electrical heating apparatus is operated, and the cooling fan 42 for cooling the power PCB and the like in the main body 2 is operated as well.

When the cooling fan 42 is operated, outer air is flowed into the main body 2, and the flowed air flows toward the porous cooling plate 96 adhered to the heat generating device 95 of the power PCB 90.

Herein, since, at the porous cooling plate 96, a plurality of holes is formed, and so an area being in contact with air is more obtained than that of

the conventional cooling pin, so that heat transmission efficiency is improved, and thus the heat generating device 95 can be effectively cooled.

That is, on the assumption that the porous cooling plate of the present invention and the conventional cooling plate have the same size, the heat transmission efficiency of the conventional plate is 15-22%, but the heat transmission efficiency of the porous cooling plate is 90-100%. Accordingly, the porous cooling plate 96 can cool a high temperature heat generating device more effectively than the conventional cooling plate.

Thereafter, air, which has cooled the heat generating device 95 and the porous cooling plate 96, cools the inside of the main body 2, with flowing along an air flowing direction, and then is discharged to the outside.

In an cooling apparatus for a cooker according to the present invention constructed and operated as above, since, in a condition that a displaying unit is installed at a lid, a power PCB is positioned at the rear portion of a main body, and a cooling fan is positioned in front of the power PCB, wiring between the display unit and the power PCB becomes easy and the whole height of the main body can be reduced as well.

Also, in the present invention, a guide structure is formed at a part of a tripod type support body for supporting an oven so as to concentratedly cool a heat generating device of the power PCB, and a cooling fan is integrally installed at the guide. For this reason, cooling efficiency for a heat generating source is improved, and, since the whole structure of the cooker is simplified, a product can be assembled and produced easily as well.

In addition, since the cooling apparatus is constructed so as to cool a heat generating device with using a cooling plate and a turbulator, cooling efficiency with respect to a cooling area is maximized.

In addition, since the cooling apparatus is constructed so as to cool a heat generating device with using a porous heat sink, cooling efficiency with respect to a volume can be increased, thus a high temperature heat generating device can be easily cooled, and a plan and a disposition for the inside of the cooker becomes easy, too.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.