JP2004008272A - Structure for washing machine and washing and drying machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure for improving heat radiation efficiency, the structure for improving a waterproof performance even in such a state and the structure for improving workability for a power component and a heat sink on a printed board loaded on a washing machine and a washing and drying machine. <P>SOLUTION: In order to improve heat radiation, a cylindrical structure is provided on a board case so as to be positioned between the fin part of the heat sink and a hole for inserting the cylindrical structure is provided on the printed board. In the case of covering with a board cover, the hole is provided on at least a part of a surface at a fin lower part or in the tip direction of the fin parallel to a heat radiation plate. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a washing machine and a washing / drying machine having a power component and a heat sink for radiating the power component in an electronic control unit.
[0002]
[Prior art]
A washing machine and a washing / drying machine may be installed in a high humidity environment such as a bathroom. In addition, since water is collected during washing and rinsing, the air inside the main unit is cooled by this water, so dew condensation easily occurs inside the main unit.When mounting a printed circuit board on a washing machine or washing and drying machine, take waterproof measures. Required.
[0003]
Usually, the printed circuit board is held in a board case, and the entire soldering surface of the printed circuit board and a part of the charged part of the electronic control component on the component surface are covered with a potting material. Also, when the printed circuit board is arranged in the horizontal direction, the component surface is directed downward to prevent water from accumulating on the printed circuit board surface and the connector.
[0004]
FIG. 2 is an exploded view of a conventional example in which a power component and a heat sink for dissipating the power component are mounted in a direction in which a fin portion is perpendicular to a printed circuit board in a state where the above-described waterproofing measures are taken (FIG. 2). (Perspective view). (From this figure, only the power component 24 and the heat sink 23 or only the heat sink 23 are shown on the printed circuit board 22 and the other electronic components are omitted, but they are also mounted on other electronic components. The broken line used in the exploded view indicates that one part moves on the broken line and is attached to the other part.)
The power component 24 is fixed to the heat sink 23 with the screw 25, and is mounted on the printed circuit board 22 in that state. After the printed circuit board 22 is soldered upside down from FIG. 2, it is put in the board case 21 and held, and then the solder surface and part of the component surface are covered with a potting material.
[0005]
When the operation of the washing machine starts and the power component 24 generates heat, the air around the printed circuit board 22 warms and convection occurs. Normally, warm air convects upward, but in the structure shown in this example, as shown in FIG. 3 (perspective view), the upper parts around the power components 24 and the heat sink 23 are formed by the printed circuit board 22 and the board case 21. Because it is blocked, air convection is impeded. For this reason, the side surfaces and a part of the lower surface of the fin portion were opened to secure the ventilation passage, but the heat radiation efficiency was poor.
[0006]
[Problems to be solved by the invention]
The warm air convects upward along the heat sink, but in the above-described structure, the upper portion is blocked, so that the convection of the air is poor and the heat radiation efficiency of the heat sink is low.
[0007]
An object of the present invention is to improve the heat dissipation efficiency of a heat sink by opening the upper surface of the heat sink to improve the convection of air, to improve the waterproof performance even in such a state, and to facilitate the assembly process. Is to provide.
[0008]
[Means for Solving the Problems]
The feature of the present invention is that in order to open the upper surface of the heat sink, to promote convection of air, and to suppress the intrusion of water from the upper surface, the tube case is provided on the substrate case so as to be located between the fin portions of the heat sink. And a hole for inserting the tubular structure is provided in the printed circuit board.
[0009]
A feature of the present invention is that, in the first aspect, even in the case where a board cover for covering the component surface of the printed circuit board is provided, in order to secure a ventilation passage, the fin tip direction or the fin tip direction horizontal to the heat radiating plate. Hole is provided in at least a part of the surface of.
[0010]
Also, the feature of the present invention is that, in the first invention, a hole is provided at a lower position of a heat sink on a bottom surface of a substrate cover to further improve a waterproof performance while securing a ventilation path, and further, a heat radiation plate is formed from the bottom surface. That is, a wall is provided so as to horizontally cover the tip of the fin.
[0011]
Also, a feature of the present invention is that, in the first, second, and third inventions, in order to facilitate the work of separating the discarded substrate in the printed circuit board, holes of the printed circuit board are arranged on the end surface of the printed circuit board, Instead of a hole, the end face has a U-shape.
[0012]
Also, a feature of the present invention is that, in the fourth invention, in order to promote convection from the surface of the heat sink of the heat sink and the horizontal direction of the fin portion, a tubular structure provided on the board case is provided with the heat sink of the heat sink. It is arranged on the end face of the board case with the surface of the horizontal fin tip direction outside, and at least a part of the face of the horizontal fin tip direction is opened to the heat sink of the board case or the board cover. This is to cover along the side surface or the end surface to shield the inside and outside of the substrate cover around the heat sink.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a vertical sectional side view of a washing / drying machine according to an embodiment of the present invention, and the main components are introduced below. An outer tub 3 supported by a plurality of suspensions 2 is provided inside the outer frame 1, a washing tub 4 is provided therein, a pulsator 5 for stirring is provided at the bottom thereof, and a main motor 17 is arranged coaxially with its axis. The inserted drive unit 6 is located. In the top cover 7 on the upper surface portion, a display substrate 8, a drying heater 10, a detergent dissolving unit 11, a bath water supply pump 12, and the like are also stored. The main board 9 for controlling each electric component is disposed at a portion near the bottom of the outer tub 3, and is connected to each electric component by a wire harness. A motor 13 for a blower fan is provided at the lower rear portion of the outer tub 3 to circulate the heat generated by the heater into the washing tub to dry the laundry in the washing tub 4 and condense air containing a large amount of steam. In 14, it is effectively dried by cooling with tap water and condensing. A drain valve 16 is provided below the outer tub 3, and is closed during washing and rinsing to store water in the outer tub 3. After the washing and rinsing operations, and at the time of dehydration, the drain valve 16 is opened to drain the water through the drain hose 17. Also, the drain valve 16 is opened during the drying operation to discharge the condensed water. Usually, the washing machine and the washer-dryer are installed in the waterproof pan 18, and the drained water is stored in the waterproof pan and then gradually sent to the outside. For this reason, water may always accumulate in the waterproof pan.
[0014]
As for the washing machine, since the washing and drying machine shown in FIG. 1 does not have a drying function, only parts such as a drying heater 10, a condensing device 14, and a blowing fan motor 13 are eliminated. Same as 1.
[0015]
During the washing and rinsing operations, water is collected in the outer tub 3 and the water and the laundry are stirred by the washing tub 4 and the pulsator 5. Since the air is cooled, dew condensation easily occurs inside these. Further, when the dew condensation generated inside the outer frame 1 drops, the water accumulated in the waterproof pan 18 rebounds and the water droplets are scattered. Furthermore, there is a case where the apparatus is installed in a high humidity environment such as a bathroom, and intrusion of moist air into the inside of the main body is inevitable.
[0016]
Under these circumstances, when the printed circuit board 22 is usually provided in the washing machine, a part of the charged part of the electronic component on the solder surface and the component surface is covered with a potting material as a waterproof measure. When the printed circuit board 22 is placed horizontally, the surface of the component faces downward so that water hardly accumulates on the connector and the surface of the potting material.
[0017]
FIG. 4 is an exploded view (perspective view) showing an embodiment of the first invention. The mounting state of the power component 24 and the heat sink 23 is the same as in FIG. According to the present invention, the substrate case 21 is provided with a tubular structure 21a between the fins 23a of the heat sink 23 in the direction of the upper surface of the heat sink 23, and the printed circuit board 22 has a size capable of inserting the tubular structure 21a. It is characterized in that a hole 22a is provided. It is assumed that the cylindrical structure 21a has a sufficient height so that the potting material does not overflow. When the heat sink 23 is supported by the printed circuit board 22, the hole 22a has a shape that can be supported (the supporting portion is not a hole).
[0018]
In FIG. 4, the cylindrical structure 21a is provided between each of the fin portions 23a of the heat sink 23. However, the present invention includes a case where there is a place where no fin is provided.
[0019]
FIG. 5 shows a mounting example (perspective view) of the first invention. By providing the hole 22a and the cylindrical structure 21a, the upper surface of the heat sink 23 is opened, and the surrounding air can convect upward along the fin portion 23a and the heat radiating plate 23b, thereby improving the heat radiation efficiency. Also, by making the height of the cylindrical structure 21a sufficient, the potting material does not leak. Further, since the droplets flowing down from the substrate case 21 flow downward along the cylindrical structure 21a and the heat sink 23, the droplets do not accumulate on the surface of the potting material and the electronic components on the printed circuit board 22 do not get wet.
[0020]
In the state shown in FIG. 3 or FIG. 5, water splashing from below is splashed on the electronic components on the printed circuit board 22. Therefore, the board cover 26 is usually provided so as to cover the component surface side of the printed circuit board 22. FIG. 6 shows an embodiment of the second invention in an exploded view (perspective view). Even when the substrate cover 26 is provided, a slit or the like is provided on either the lower surface of the heat sink 23 or a part of the surface of the fin portion 23a in the direction of the tip end which is horizontal with the heat radiating plate portion 23b to secure the ventilation path 26c. Air can flow from the case 21 or the substrate cover 26, and the effects of the hole 22a and the cylindrical structure 21a described in the first invention can be enjoyed.
[0021]
FIG. 7 shows an embodiment (cross-sectional view) of the third invention. According to the present invention, the tip of the fin portion 23a of the heat sink 23 is closed in order to prevent water droplets entering from the cylindrical structure 21a from contacting the charged portion of the electronic component on the printed circuit board 22 or from accumulating in the board case 26. Then, a wall is provided on the substrate case 26. Further, in order to ensure ventilation, an opening 26b is provided below the heat sink. According to the present invention, the waterproof performance can be improved while enjoying the effect of improving the heat radiation efficiency according to the first invention.
[0022]
FIG. 8 is a plan view showing a general structure example in the case where the holes 22a are provided in the printed circuit board 22. When electronic components are mounted on the printed circuit board 22 and then soldered, if there is a large hole in the printed circuit board, there is a problem that solder blows up from the solder tank to the component surface. For this reason, as shown in FIG. 8, a discarded board 22b connected to the outer peripheral portion by a slit is provided so that the hole 22a is closed before soldering and separated after soldering. In order to separate the discarded board 22b, for example, in FIG. 8, it is necessary to apply a stress in the rotating direction to the split white, and it is necessary to push from both the solder side and the component side of the printed board, and the work efficiency is poor.
[0023]
According to a fourth invention, in the first, second, and third inventions, the heat sink 23 and the hole 22a of the printed board 22 are arranged on the end face of the printed board 22, and the end face of the printed board 22 is formed into a U-shape. Structure. FIG. 9 is a plan view showing an embodiment of the fourth invention. By arranging the hole 22a on the end face of the printed circuit board 22, the discarded board 22b can be sandwiched by, for example, a pair of pliers, and the separating operation can be performed only by twisting the printed circuit board 22 in a direction perpendicular to the split white. Is good.
[0024]
The fifth invention is different from the fourth invention in that a tubular structure 21a is arranged on the end surface of the substrate case 21, and a part of a lower surface of the heat sink 23 and a horizontal fin portion 23a are formed on the heat radiating plate portion 23b. Is a structure in which a part of the substrate case 21 or the substrate cover 26 in the front end direction is opened. An embodiment is shown in an exploded view (perspective view) in FIG. In the embodiment, the surface along the outer surface of the cylindrical structure 22a of the heat sink 23 is opened to improve the convection of air. Further, in order to prevent water from entering the inside of the substrate cover 26 from the open surface, the peripheral portion of the heat sink 23 of the substrate cover 26 is formed to have a shape 26a that covers the side surface of the fin portion and the lower end of the fin portion.
[0025]
【The invention's effect】
According to the first invention, a ventilation path in the upper direction of the heat sink can be secured, and convection of air is promoted. Therefore, the size of the heat sink can be reduced, the rated power of the power component can be reduced, and the cost can be reduced. Parts can be used, and an economical washing machine and washing / drying machine can be provided. Further, the cooling effect of the power components is enhanced, and the reliability against thermal destruction is improved.
[0026]
According to the second aspect, the effects of the first aspect can be enjoyed even when the board cover is provided.
[0027]
According to the third aspect of the present invention, the waterproof performance is increased as compared with the first aspect, and rust due to stagnation of the drops on the potting surface and drop adhesion to the charged part of the electronic component, and electrical malfunction are prevented, and product reliability is improved. Improve the performance.
[0028]
According to the fourth aspect, the work of separating the discarded board provided on the printed board to realize the first, second, and third structures is facilitated, and the workability is increased.
[0029]
According to the fifth invention, the waterproof performance can be improved as compared with the first, second, and third inventions, and the convection of air can be increased as compared with the second and third inventions. Can be increased.
[Brief description of the drawings]
FIG. 1 is a vertical sectional side view of a washing / drying machine.
FIG. 2 is a mounting view (exploded view) of a power component and a heat sink of a conventional example.
FIG. 3 is a mounting diagram of a conventional power component and a heat sink.
FIG. 4 is a perspective view of the first invention of the present invention.
FIG. 5 is a diagram showing a mounting example of the first invention of the present invention.
FIG. 6 is a perspective view of a second invention of the present invention.
FIG. 7 is a sectional view of a third invention of the present invention.
FIG. 8 is a plan view showing a conventional example.
FIG. 9 is a plan view of a fourth invention of the present invention.
FIG. 10 is a perspective view of a fifth invention of the present invention.
FIG. 11 is a perspective view of a fifth invention of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Outer frame, 2 ... Suspension, 3 ... Outer tub part, 4 ... Washing tub, 5 ... Pulsator, 6 ... Driver, 7 ... Top cover part, 8 ... Display board, 9 ... Main board, 10 ... Drying Heater, 11: detergent melting motor, 12: bath water pump motor, 13: blower fan motor, 14: condenser, 16: drain valve, 17: drain hose, 18: waterproof pan, 21: board case, 21a ... Cylindrical structure, 22: printed board, 22a: hole, 22b: discarded board, 23: heat sink, 23a: fin portion, 23b: heat sink, 24: power component, 25: screw, 26: board cover, 26a: fin A shape to cover along the side surface and the lower end of the fin, 26c ... ventilation passage.

Claims (5)

The printed circuit board is placed horizontally with the component surface facing downward, and the power components and the heat sink that dissipates heat are mounted on the printed circuit board so that the fins are oriented perpendicular to the printed circuit board. Holding and covering the entire solder surface and a part of the electronic component on the component surface with a potting material, in a washing machine having an electronic control unit, a washing and drying machine,
A washing machine and a washing and drying machine are characterized in that the board case is provided with a tubular structure so as to be located between the fins of the heat sink, and the printed board is provided with holes for inserting the tubular structure. Construction. In claim 1,
A structure of a washing machine and a washing / drying machine, wherein a hole is provided in a substrate cover covering a component surface of a printed circuit board, at least at a part below a fin or at a part of a surface in a direction of a fin tip horizontal to a heat sink. In claim 1,
A structure of a washing machine and a washer / dryer, wherein a hole is provided at a position below a heat sink on a bottom surface of a substrate cover, and a wall is provided from the bottom surface to a radiator plate so as to horizontally cover a tip of a fin. In any one of claims 1 to 3,
A structure of a washing machine and a washing / drying machine, wherein a hole of a printed board is arranged on an end face of the printed board, and not a hole but an end face is formed in a U-shape. In claim 4,
The cylindrical structure provided on the board case is placed on the end face of the board case, with the surface of the fin portion horizontal to the heat sink of the heat sink facing outward, and the fin portion horizontal to the heat sink of the board case or board cover. A washing machine and a washing / drying machine, characterized in that at least a part of the surface is opened, and furthermore, the inside and outside of the board cover are shielded around the heat sink by covering the heat sink around the side surface or the end surface of the heat sink.

Images