Cooling structure for electrical equipment

Abstract

An object of the present invention is to provide a cooling structure capable of cooling components that are arranged offset in a direction intersecting the airflow direction of a cooling fan. [Solution] A fan holder (23) has a blower (25), a receiver (26), a guide (27), and an exhaust (28). The receiver (26), guide (27), and exhaust (28) are connected so that air can pass through, forming a second air flow path (41). A temperature sensor board (21) is disposed near the exhaust (28). A portion of the air sent out horizontally from the fan (22) hits the receiver (26), passes through the guide (27), and is exhausted from the exhaust (28), and this air hits the temperature sensor board (21). The air flowing through this second air flow path (41) can cool the temperature sensor board (21).

Description

[Technical Field]

[0001] The present invention relates to a cooling structure for components arranged inside an electric device. [Background technology]

[0002] Conventionally, a known cooling structure for this type of electrical equipment is one in which a magnetron, a high-voltage transformer, a cooling fan, and a shielding plate that guides the air flow of the cooling fan are arranged inside a microwave oven, and the air from the cooling fan is directed at the magnetron and the high-voltage transformer to directly cool them (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-339446 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with this type of cooling structure, the components to be cooled must be placed on the side of the cooling fan's airflow direction, which makes it difficult to cool components that are positioned in a direction that intersects with the cooling fan's airflow direction.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a cooling structure that can easily cool components that are arranged offset in a direction intersecting the airflow direction of a cooling fan. [Means for solving the problem]

[0006] The cooling structure for an electrical device described in claim 1 of the present invention is a cooling structure for an electrical device having a first body to be cooled, a second body to be cooled, a fan, and a fan holder therein, wherein the fan holder has a blowing section, a receiving section, a guide section, and an exhaust section, and the receiving section, the guide section, and the exhaust section are configured to allow air to pass through, the fan is fixed to the fan holder, the blowing direction of the fan is a first air flow path, the first cooling body is arranged within the first air flow path, the second cooling body is arranged offset in a direction intersecting the blowing direction of the fan, the receiving section is arranged so as to block part of the first air flow path downstream of the blowing section in the blowing direction of the fan, the path along which air that hits the receiving section passes through the guide section and is exhausted from the exhaust section is a second air flow path, and the exhaust section is arranged offset in a direction intersecting the blowing direction of the fan, and the second cooled body is configured to receive air from the exhaust section.

[0007] The cooling structure for an electric device according to claim 2 of the present invention is the same as claim 1, in that the second body to be cooled is disposed on the opposite side of the air blowing direction of the fan than the air blowing section.

[0008] The cooling structure for an electric device according to claim 3 of the present invention is the same as claim 1 or 2, in which the second body to be cooled is fixed to the fan holder. [Effects of the Invention]

[0009] By configuring the cooling structure for electrical equipment described in the present invention as described above, even if the second cooled body is positioned offset in a direction intersecting the air flow direction of the fan, the second air flow path can receive air from the exhaust section, thereby cooling the second cooled body.

[0010] Furthermore, by arranging the second cooled body on the opposite side of the fan's blowing direction than the blowing section, the cooled body can be arranged at a greater distance, thereby increasing the freedom of component arrangement.

[0011] Furthermore, by fixing the second object to be cooled to the fan holder, the number of parts can be reduced, leading to further cost reduction. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view of a microwave oven showing an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a main part of the cooling structure of the microwave oven. [Figure 3] FIG. 2 is a front view of the main part of the cooling structure of the microwave oven. [Figure 4] FIG. 2 is a right side view of the main part of the cooling structure of the microwave oven. [Figure 5] FIG. 2 is a cross-sectional view of a second air flow path of the microwave oven according to the first embodiment. [Figure 6] FIG. 2 is a cross-sectional view of a second cooled object of the microwave oven. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to Figures 1 to 6. Note that the electric device of this embodiment will be described assuming a microwave oven, but the present invention is not limited to microwave ovens and can also be used for other electric devices.

[0014] In the description of the embodiment, the lower left direction in FIG. 1 is the front, the upper right direction is the rear, the lower right direction is the right, and the upper left direction is the left.

[0015] Reference numeral 1 denotes a microwave oven as an electric appliance according to an embodiment. This microwave oven 1 comprises a main body 2 and a door 3. The main body 2 and the door 3 are connected by hinge mechanisms 4, 4 provided on the top and bottom of the left side of the main body 2, and these hinge mechanisms 4, 4 allow the door 3 to be freely opened and closed relative to the main body 2.

[0016] In addition, an operation unit 5 and a display unit 6 are provided on the right side of the front of the main body 2, and this operation unit 5 can be used to select a mode, set the heating time, start heating, etc., and the display unit 6 displays the selected mode, remaining heating time, etc. (Explanation of each mode and display content will be omitted.)

[0017] The main body 2 has a heating chamber 7 and a machine chamber 8. The heating chamber 7 is a space surrounded by the door 3, an inner cover 9, a top panel 10, a rear panel 11, and a bottom panel 12. Food 32 or the like is placed in the heating chamber 7 as an object to be heated.

[0018] The inner cover 9 has a left inner wall 13, a right inner wall 14, and an inner bottom surface 15, and is shaped like an open U at the top. The top plate 10 is fixed to the top of the inner cover 9, the rear plate 11 is fixed to the rear side of the inner cover 9, the bottom plate 12 is fixed near the center of the inner bottom surface 15, and the door 3 covers the front side of the inner cover 9, thereby forming the heating chamber 7. The inner cover 9, the top plate 10, and the rear plate 11 are made of cold-rolled steel plate, and the bottom plate 12 is made of heat-resistant glass.

[0019] The machine chamber 8 is a space surrounded by the right inner wall 14 and the front, top, back, right side and bottom of the main body 2, and is located to the right of the heating chamber 7. In the machine chamber 8, a magnetron 20 as a first object to be cooled and a temperature sensor board 21, a fan 22 and a fan holder 23 as second objects to be cooled are disposed.

[0020] The magnetron 20 is fixed with screws or the like to the machine chamber 8 side on the upper center of the right inner wall 14. The fan 22 is fixed with screws to the fan holder 23, and the temperature sensor board 21 is fixed with a press fit or the like to a board holder 24, which is fixed with screws to the fan holder 23. The fan holder 23 is then fixed to the rear surface of the main body 2 or the right inner wall 14 with screws or the like.

[0021] The fan holder 23 is disposed behind the magnetron 20, and the fan 22 is disposed slightly below the rear of the magnetron 20. The air blowing direction of the fan 22 is the horizontal direction in front of the microwave oven 1.

[0022] The fan holder 23 also has a blowing section 25, a receiving section 26, a guide section 27, and an exhaust section 28. The blowing section 25 is the position where air is blown by the fan 22, and in this embodiment, it is the front surface of an arc-shaped rib 29 of the fan holder 23. The diameter of the wall of the arc-shaped rib 29 on the fan 22 side is slightly larger than the diameter of the circle that forms the path of the tips of the fan 22 blades.

[0023] The receiving portion 26, the guide portion 27, and the discharge portion 28 are continuously connected to allow air to pass through. The receiving portion 26 is disposed inside a circle that is the locus of the tips of the blades of the fan 22. In other words, the receiving portion 26 is disposed within the air blowing range of the fan 22.

[0024] As described above, the temperature sensor board 21 is fixed to the board holder 24 by a snap fit or the like. The board holder 24 is then fixed to the fan holder 23 with screws and is disposed near the exhaust section 28, offset upward with respect to the axis of the fan 22, i.e., the airflow direction, and at a position rearward of the air blower section 25. In other words, the temperature sensor board 21 is offset in a direction intersecting the airflow direction of the fan 22 and is disposed on the opposite side of the airflow direction of the fan 22 from the air blower section 25. A temperature sensor 30 is attached to the temperature sensor board 21. The temperature sensor 30 is an infrared sensor, and measures the temperature of the object to be heated placed in the heating chamber 7 through a hole 31 in the right inner wall 14.

[0025] Next, the effects of this embodiment will be described. Here, we will take as an example a case where food 32 placed in heating chamber 7 as an object to be heated is heated in an automatic mode that stops heating when the food reaches a predetermined temperature.

[0026] A user opens the door 3, places the food 32 in the heating chamber 7, and closes the door 3.

[0027] Then, the automatic mode is selected from among the multiple modes on the operation unit 5, and the start button is pressed to start heating.

[0028] When the start button is pressed, the magnetron 20 is activated to generate microwaves and heat the food 32 in the heating chamber 7. At the same time, the fan 22 also starts operating to start blowing air, and the temperature sensor 30 also starts measuring the temperature of the food 32.

[0029] When the magnetron 20 is activated, it generates heat and therefore needs to be cooled. This cooling is achieved by directing the airflow generated by the fan 22 in the forward horizontal direction directly onto the magnetron 20. The airflow path that cools the magnetron 20 is the first airflow path 40.

[0030] To explain this first air flow path 40 in more detail, air is taken in through an intake hole (not shown) on the rear surface of the main body 2, sent out horizontally forward by the fan 22, passes through the magnetron 20 to cool it, and is then discharged from an exhaust hole (not shown) on the bottom surface of the main body 2.

[0031] The temperature sensor board 21 also needs to be cooled. Although the temperature sensor board 21 itself does not generate much heat, heat from the magnetron 20 is transferred through the right inner wall 14 and the air in the machine chamber 8, raising the temperature of the temperature sensor board 21. Furthermore, as the food 32 is heated, the heat is also transferred through the air in the heating chamber 7, raising the temperature of the temperature sensor board 21.

[0032] Due to the heat transfer, the temperature of the temperature sensor board 21 exceeds the allowable temperature of the components mounted on the temperature sensor board 21. To prevent this, cooling is required.

[0033] The temperature sensor board 21 is cooled by part of the airflow generated by the fan 22. This airflow hits the receiving portion 26 arranged in front of the fan 22, flows along the guide portion 27, and is discharged from the discharge portion 28. The temperature sensor board 21 is cooled by the airflow discharged from the discharge portion 28. The airflow path that cools the temperature sensor board 21 is a second airflow path 41. To explain this first air flow path 41 in more detail, air taken in through an intake hole (not shown) on the rear surface of the main body 2 is blown out horizontally forward by the fan 22, and part of the blown out air hits the receiving portion 26, passes through the guide portion 27, and flows from the exhaust portion 28 towards the temperature sensor board 21. This is the path where the air is exhausted from an exhaust hole (not shown) on the rear surface of the main body 2. The amount of air hitting the temperature sensor board 21 is smaller than the amount of air hitting the magnetron 20, but is sufficient for cooling.

[0034] When the temperature measured by the temperature sensor 30 reaches a predetermined temperature, it is determined that the temperature of the food 32 has reached the predetermined temperature, and the operation of the magnetron 20 and the fan 22 is terminated.

[0035] In this way, by using the first air flow path 40 and the second air flow path 41, the magnetron 20 and the temperature sensor board 21, which are located apart from each other, can be cooled by the single fan 22.

[0036] Furthermore, the magnetron 20 and the temperature sensor board 21 can be cooled sufficiently, so that their operation can be stabilized.

[0037] Furthermore, since the temperatures of the magnetron 20 and the temperature sensor board 21 are prevented from exceeding the allowable temperature, breakdowns in the components can be avoided.

[0038] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention. For example, although a propeller fan is used in this embodiment, a receiving portion may be provided at the outlet of the sirocco fan to serve as a second airflow path. Furthermore, the present invention is not limited to the microwave oven of this embodiment, and can be used in any electrical appliance in which the object to be cooled is positioned in front of the fan and offset in a direction intersecting the fan's airflow direction. [Explanation of symbols]

[0039] 1. Microwave oven (electrical appliance) 20 Magnetron (first cooled body) 21 Temperature sensor board (second cooled body) 22 Fans 23 Fan Holder 25 Blower 26 Receiving Department 27 Guide section 28 Discharge section 40 First ventilation route 41 Second ventilation route

Claims

1. A cooling structure for an electrical device having therein a first body to be cooled, a second body to be cooled, a fan, and a fan holder, the fan holder has a blowing portion, a receiving portion, a guide portion, and an exhaust portion, and the receiving portion, the guide portion, and the exhaust portion are configured so that air can pass through; the fan is fixed to a fan holder, the airflow direction of the fan is a first airflow path, the first cooling body is disposed within the first airflow path, and the second cooling body is disposed offset in a direction intersecting the airflow direction of the fan, A cooling structure for electrical equipment characterized in that the receiving portion is arranged so as to block a portion of the first air flow path downstream of the blowing portion in the air flow direction of the fan, the path along which the air that hits the receiving portion passes through the guide portion and is discharged from the discharge portion is a second air flow path, the discharge portion is arranged offset in a direction intersecting the air flow direction of the fan, and the second cooled body is configured to receive the air from the discharge portion.

2. 2. The cooling structure for an electrical device according to claim 1, wherein the second body to be cooled is disposed on the opposite side of the airflow direction of the fan than the air blowing section.

3. 3. The cooling structure for an electrical device according to claim 1, wherein the second object to be cooled is fixed to the fan holder.

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