JPH0719145Y2 - Coding lower type of control unit such as washing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a lower coating mold in a control unit for controlling input / output of a washing machine or the like.

(Prior Art) Conventionally, a control unit shown in FIGS. 3 to 5 is known as this type of control unit. The control unit to which the present invention relates includes a control unit (3) including a board (1) and electronic components (2) mounted thereon, as shown in FIG.
As shown in FIG. 4, it was sandwiched between the lower mold (4) and the upper mold (5), and the upper and lower surfaces were coated so that the lead legs of the electronic component (2) were buried. During the coating, the positioning boss (4a) of the lower mold (4) and the holding boss (5a) of the upper mold (5) are aligned. After coating, the upper mold (5) and the lower mold (4) were removed to obtain a control unit (6) as a coating body.
FIG. 5 shows an example of a conventional control unit.
The conventional lower mold (4) was made of metal and was used repeatedly with the upper mold (5). When the upper die and the lower die were removed, a proper number of positioning boss holes (7) and restraining boss holes (8) were formed as shown in FIG. The mounting of the control unit (6) on the operating panel is done using these holes (7), (8). (9) is a coating agent.

(Problems to be solved by the invention) As described above, the conventional lower mold must be removed together with the upper mold after coating, and depending on the coating, it is not easy to remove the lower mold, resulting in poor workability and production. There was a problem of inhibiting sex.

An object of the present invention is to eliminate the above-mentioned problems of the prior art, and therefore to provide a lower control unit coating unit of a control unit which has excellent workability and can improve productivity.

(Means for Solving the Problem) A feature of the lower coating die according to the present invention is that it is formed as a thin plastic member by vacuum forming, and has a positioning boss provided with blind holes.

(Operation of means for solving the problem) The lower mold according to the present invention does not need to be removed after coating,
It is attached to the operation panel as a part of the control unit. Therefore, the work of removing the lower mold is not necessary, and the workability is remarkably improved. In addition, the positioning boss with blind holes makes it easy to install, improving work speed.

(Embodiment) FIGS. 1 and 2 show an embodiment of the present invention, in which the same members or portions as those of the conventional one described with reference to FIGS. 3 to 5 are designated by the same reference numerals. . The lower coating mold (10) according to the present invention is formed as a thin plastic member. The forming is preferably performed by vacuum forming, but it may be formed by other methods if desired. FIG. 1 shows an example of the lower mold (10) of the present invention. Generally, since the control unit (6) is generally rectangular parallelepiped, the lower mold (10) has a rectangular bottom wall (11) and its shape. Surrounding 4
It consists of a peripheral wall (12) on the side, and has a positioning boss (13) at a predetermined position on the bottom wall.

Further, in this lower mold (10), concentric blind holes are formed in each positioning boss (13) as shown clearly in FIG. 2, and the blind holes form a screw on the positioning boss (13). It allows the screws for mounting the control unit to pass through. Preferably, along the entire circumference of the peripheral wall (12), a sloping portion (14) inclined outward and upward is provided at the top thereof, thereby preventing the coating agent from overflowing. More preferably,
Vertical part (15) on top of the sloped part (14) as shown
Is provided.

When the control part (3) is coated with the lower mold (10), the control part (3) is placed on the lower mold (10) as in the conventional case, and the positioning boss (13) is placed on the substrate (1). ) Is positioned. When the upper die (5) is set thereon, the lower die positioning boss (13) is aligned with the upper die restraining boss (5a).

After sandwiching the control part (3) between the lower mold (10) and the upper mold (5) for coating, the upper mold (5) is removed, but the lower mold (10) is not removed and the control is performed. It becomes a part of the unit (6) and is attached to the operation panel. Second
As shown in the drawing, when the upper mold (5) is removed, the lower mold positioning boss (13) is aligned with the holding boss hole (8) formed in the coating agent. The control unit (6) is attached by aligning the fixed boss on the operation panel with the holding boss hole (8) of the control unit (6) and inserting a screw through the positioning boss (13).

According to the above-described embodiment, since the opening area of the blind hole of the positioning boss is smaller than the opening area of the boss hole, for example, in the step of mounting the screw from the blind hole side to the boss hole side, the screw is hard to tilt and the boss hole There is little deviation from the center. In other words, the blind hole acts as a kind of guide for the screw to enter vertically.

Therefore, it is less likely that a screw will enter the resin on the boss hole side due to the misalignment of the screw and the circuit pattern portion coated with the resin will be short-circuited as the screw enters. Therefore, the opening area of the boss hole can be set without considering the possibility of such a short circuit, so that the effective area of the circuit pattern portion can be sufficiently obtained, and the area of the resin portion can be made approximately the same as the area of the circuit pattern portion. In consideration of the possibility of the short circuit described above, it is not necessary to make the area of the circuit pattern portion smaller than the area of the resin portion, which leads to downsizing of the substrate.

Also, the control unit using this lower coating mold,
For example, as shown in FIG. 2 of the present application, a screw is passed through the blind hole and attached to a fixing portion (not shown). After the attachment, the upper wall surface (wall surface on which the substrate is placed) formed by the blind hole Of the peripheral part of the part where the screw directly penetrates,
In other words, the part surrounding the screw is the upper and lower sides of the board,
Performs a packing function for water. In particular, since many holes are usually formed in the substrate, the effect of this packing function is great.

In this way, the upper wall surface of the blind hole fulfills the function of positioning the screw holes attached to the printed circuit board when the printed circuit board is installed, and the support function of the printed circuit board when the resin agent is injected after the installation. In addition, after the resin agent is injected and after it is mounted as a control unit, the packing function is fulfilled, and the function corresponding to that stage is fulfilled at various stages.

(Effects of the Invention) As described above, according to the present invention, the relatively difficult work of removing the lower mold is unnecessary, so that the workability can be significantly improved. In addition, conventionally, management of the upper mold and the lower mold is required, but management of only the upper mold is sufficient, which facilitates component management. Further, since the blind hole of the positioning boss plays a role of a guide for the mounting screw, the mounting by the screw is facilitated, and the workability is further improved in combination with the above matters.

In addition, the effective area of the circuit pattern portion of the printed circuit board can be increased, which leads to improvement of the effective density.

Further, the packing function for water on the upper and lower sides of the printed circuit board can be realized by the blind hole.

[Brief description of drawings]

FIG. 1 is a perspective view of a lower coating die according to an example of the present invention, FIG. 2 is a sectional view of a control unit having the lower die of the present invention, and FIG. 3 is a perspective view of an example of a control unit including a substrate and electronic components. FIG. 4, FIG. 4 is an elevational view showing one step of a conventional coating on a control unit, and FIG. 5 is a sectional view of the conventional control unit. In the figure, 1: substrate, 2: electronic component, 3: control part, 5: upper mold, 6: control unit, 10: lower mold, 13: positioning boss

Front page continued (72) Taketsugu Sugino 1-1-1, Yamate, Funabashi, Chiba, Japan Inside the Funabashi Plant of Nippon Steel Co., Ltd. (72) Hirofumi Urabe 1-1-1, Yamate, Funabashi, Chiba Japan-built Ironworks Co., Ltd. Funabashi Manufacturing Co., Ltd. (56) References: Showa 50-13947 (JP, U) Showa 53-139206 (JP, U) Showa 55-42446 (JP, Y2) Showa 57-49396 (JP, Y2)

Claims (1)

[Scope of utility model registration request] 1. A lower mold for coating a control part of a washing machine or the like, which is composed of a substrate and electronic parts mounted on the substrate, and which is mounted with screws by a boss hole by sandwiching the control part with the upper mold, wherein the lower mold is thin-walled. Has a positioning boss that is formed as a plastic member of the control unit and is aligned with the upper boss hole of the control unit. Further, the positioning boss is provided with a concentric blind hole through which a mounting screw can be inserted. An opening area of the hole is set smaller than an opening area of the boss hole, which is a lower coating mold for a control unit of a washing machine or the like.