JPH0680903B2 - Electronic controller storage device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a storage case for an electronic controller, and more particularly to a storage device suitable for an electronic controller of a device using water such as a washing machine.

[Conventional technology]

Japanese Patent Application Laid-Open No. 60-183795 discloses a storage device for an electronic controller in which electronic components are mounted with a conventional waterproof filler.
As described in Japanese Utility Model Laid-Open No. 60-30569, most of the cases have a box-shaped case mounted with the opening facing upwards, and there is no concern that the solidified waterproof filler will fall out of the case. There wasn't. However, when the opening of the case is attached and fixed upward, when water droplets or the like enter from the outside, as shown in FIG. 2, water 19 stays on the upper surface of the waterproof filling material, and the electronic component Since the waterproof effect such as corrosion and leak between component terminals decreases, a method of mounting and fixing the box-shaped case in which a waterproof filler is injected and solidified with the opening facing downward is effective for improving the waterproof performance. If the opening of the box-shaped case is attached and fixed downwards in this way, the water-repellent filling material with the embedded electronic controller may fall off from the case when the contact surface between the waterproof filling material and the case peels off. is there. The adhesive strength of the contact surface between the dehydratable filler and the resin molded case is such that it can be peeled off with a fingertip when necessary. This is because the electronic controller solidified by the waterproof filling material needs to be taken out from the case in order to repair it when a component on the electronic controller solidified by the waterproof filling material fails. Therefore, there is a possibility that the above-mentioned drop-off may occur when a particularly strong vibration or shock is applied.

[Problems to be solved by the invention]

In the above-mentioned conventional technique, the waterproof filling material and the case are fixed to each other only by the adhesive strength at the contact surface between the both, and no consideration is given to a measure for preventing the drop in case of peeling on the contact surface.

An object of the present invention is to provide an electronic controller in which the waterproof filling material in which the electronic controller is embedded is stably fixed without falling off from the case even when the contact surface between the waterproof filling material and the case is peeled off. It is to provide a storage device.

[Means for solving problems]

The present invention includes a top cover, an operation panel attached to the top cover, a case attached to the operation panel, and a printed wiring board housed in the case.
An electronic component for an electronic controller to be mounted on the printed wiring board is formed, a storage recess is formed in the top cover, a case is attached to the back side of the operation panel, and the case side is stored in the storage recess. In the electronic controller storage device that attaches the operation panel to the top cover, the case is formed in a box shape with an opening on one side, and a rising boss that floats the printed wiring board from the inner bottom surface is formed on the inner bottom of the case. The inner wall is formed with a fall prevention claw for preventing the printed wiring board from slipping out of the case. The fall prevention claw is formed on the opposite surface of the inner wall, and the fall prevention claw has an opening of the case from the tip of the claw. Form an inclined surface toward the part,
Electronic control storage characterized in that the printed wiring board held by the rising boss and the fall prevention claws is covered with a waterproof filling material that is injected into the case, and the opening side of the case faces downward. On the device.

[Action]

The printed wiring board of the controller, which is completely covered with the waterproof filler to be injected into the case, is already held by the rising boss and the fall-out preventing claw of the case before being covered.
By this holding, the printed wiring board does not drop from the case arranged so that the opening portion faces downward even if the waterproof filler is peeled from the case.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. It should be noted that although FIG. 2 has been cited as a conventional technique, it is cited to describe the infiltration of water droplets, and the others show one embodiment of the present invention.

Electronic components 1 such as transistors, ICs, resistors, capacitors, etc. are arranged on one side of the printed wiring board 2, and leads 3 of the electronic component 1 are formed on a conductor pattern (not shown) formed on the other side of the printed wiring board 2. The tip of each is fixed with solder 4, while parts 5 such as chip type transistors, diodes, resistors and capacitors are temporarily fixed on the conductor pattern with an adhesive and then dipped in a solder bath to be soldered. It is fixed at 4. On the other hand, the box-shaped case 6 formed of a thermoplastic resin is made of urethane resin or the like to a depth enough to cover the leads 3 of the electronic component 1 on the printed wiring board 2 while the printed wiring board 2 is immersed. The waterproof filler 7 is injected. In particular, when using a two-component resin composed of a main agent and a curing agent, it is necessary to sufficiently stir the two liquids so that they can be mixed uniformly. Further, if air bubbles remain inside the waterproof filler 7, the waterproof performance is deteriorated. Therefore, it is effective to vacuum degas the entire waterproof filler 7. Furthermore, when the printed wiring board 2 is dipped in the waterproof filler 7, the printed filler on which the electronic component 1 and the chip component 5 are mounted in advance in order to prevent the waterproof filler 7 from foaming due to the temperature difference between the two. It is desirable to preheat the plate 2 at 80 ° C. for about 5 minutes. Further, in order to reduce bubbles remaining on the conductor pattern side of the printed wiring board 2, when the printed wiring board 2 is embedded in the waterproof filling material 7, after the printed wiring board 2 is installed in the case 6, waterproof filling is performed. Material 7
Instead of injecting, the waterproof filler 7 is poured into the case 6 in advance, one end of the printed wiring board 2 is inclined and immersed therein, and then the waterproof filler 7 is naturally filled by its own weight. Let it sink inside. By this method, the bubbles naturally propagate to the lower surface of the printed wiring board 2 and rise, and the remaining bubbles are reduced.

The printed wiring board 2 is sunk into the waterproof filler 7, and the screw 9 is screwed into the rising boss 10 before the waterproof filler 7 is solidified, whereby the printed wiring board 2 is completed as shown in FIG. The reason why the waterproof filler 7 is also covered on the screw 9 is that the screw 9 is screwed in before the waterproof filler 7 is solidified.

The case 6 shown in FIG. 2 has a locking claw 8 on the inner wall on one side which is shorter.
Ribs having are formed. Since one of the printed wiring boards 2 is locked to the locking claw 8 and the other is stopped by the screw 9, the printed wiring board 2 is firmly fixed to the case 6.

As shown in FIGS. 1 and 2, the case 6 for accommodating the printed wiring board 2 has an inner claw portion 8 for locking the printed wiring board 2 inside one rib and a printed wiring board at the other end. A boss 10 for fixing the plate 2 with screws 9 is provided. Further, outside claws 12 for engaging with an operation panel 11 arranged so as to cover the case 6 are provided on both outer sides of the ribs of the case 6. Further, the operation panel 11 to which the case 6 is fixed is fixed to a top cover 13 which covers an upper portion of a washing machine (not shown). The operation panel 11 is provided with a switch operator 15 for turning on and off the switch on the switch plate 14 fixed to the inside of the operation panel 11 by an external operation.
A printing sheet 16 is attached to the upper surface of 15 to prevent water from entering. On the portion of the inner wall of the rib of the case 6 that is immersed in the waterproof filler 7, there is provided a claw-shaped convex portion 17 formed integrally with the case 6 and long in the direction parallel to the bottom surface of the case 6. This convex portion is provided on the longer wall surface of the rectangular case 6, and its cross section is roughly triangular or quadrangular.

As another embodiment of the present invention, as shown in FIG. 4, it is also possible to provide a continuous convex portion 17 around the entire inner circumference of the rib of the box-shaped case 6, and as shown in FIG. It is also possible to form the convex portion by fixing the separate claw 18 to the rib of the case 6.

〔The invention's effect〕

As described above, the present invention includes the top cover, the operation panel attached to the top cover, the case attached to the operation panel, the printed wiring board housed in the case, and the printed wiring board attached to the printed wiring board. Electronic parts for an electronic controller, a recess for storage is formed in the top cover, a case is attached to the back side of the operation panel, and the operation panel is mounted on the top cover so that the case side is stored in the recess for storage. In the electronic controller housing to be attached, the case is formed in a box shape with an opening on one side, a rising boss that floats the printed wiring board from the inner bottom surface is formed on the inner bottom of the case, and the printed wiring board is on the inner wall of the case. A fall prevention claw is formed to prevent it from coming out of the case. The fall prevention claw is formed on the opposite surface of the inner wall. A sloped surface is formed from the tip toward the opening of the case, and the printed wiring board that is held by the rising boss and fall prevention claws is covered with a waterproof filler that injects into the case, with the opening side of the case facing downward. The electronic controller housing device is characterized by being arranged as follows.

This configuration has the following advantages.

(1) Since the printed wiring board is covered with the waterproof filler, the insulation failure does not occur due to water or moisture.

(2) Since the case for accommodating the printed wiring board is arranged with the opening facing downward, water splashing on the outer surface of the case is transmitted along the outer surface of the case and drops downward. Since the electronic parts mounted on the printed wiring board are not splashed with water, the insulating properties of the electronic parts are not impaired.

(3) The printed wiring board held in the case by the waterproof filling material filled in the case is reliably supported by the rising boss and the fall prevention claw. Even if the adhesive bond between the waterproof filler and the case deteriorates due to the heat of the electronic component, the printed wiring board containing the waterproof filler does not fall out of the case from the case.

(4) Since the tip of the drop-out preventing claw is an inclined surface, the printed wiring board can be easily attached to the case.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a top cover portion showing an embodiment of the present invention, FIG. 2 is a vertical sectional view of a conventional electronic controller storage case, and FIG. 3 is a perspective view of an embodiment of the present invention. FIG. 4 is an inclined view of another embodiment of the present invention, and FIG. 5 is a cross-sectional view of another embodiment of the present invention. 6 ... Case, 7 ... Waterproof filler, 17 ... Convex part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuo Ishikawa 1-1-1, Higashi-Taga-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Taga factory (72) Inventor Takuo Kawaguchi 1-1-chome, Higa-taga-cho, Hitachi-shi, Ibaraki No. 1 Incorporated company Hitachi Ltd. Taga factory (56) Bibliographic reference Sho 54-13545 (JP, Y2)

Claims (1)

[Claims] 1. A top cover, an operation panel attached to the top cover, a case attached to the operation panel, a printed wiring board housed in the case, and an electronic controller attached to the printed wiring board. And an electronic component for use in the electronic device, a recess for storage is formed in the top cover, a case is attached to the back side of the operation panel, and the operation panel is attached to the top cover so that the case side is stored in the recess for storage. In the storage device, the case is formed in a box shape with an opening on one side, a rising boss is formed on the inner bottom of the case to float the printed wiring board from the inner bottom surface, and the printed wiring board is pulled out from the case on the inner wall of the case. An anti-falling claw is formed on the inner wall so as to face the inner wall. A sloped surface is formed toward the opening of the cover, and the printed wiring board that is held by the rising boss and fall prevention claw is covered with a waterproof filler that injects into the case so that the opening side of the case faces downward. The electronic control storage device is characterized in that it is arranged in.