JPH0227739Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a seal structure for a molded product that requires waterproofness, such as a solenoid valve device for switching air passages.

[Prior art]

A conventional molded solenoid valve device of this type is shown in FIG. In the figure, 1 is a bobbin, 2 is a plate, 3 is a plunger, 4 is a coil that operates the plunger 3, 5 is a take-out part (terminal) of the coil 4, 6 is a core that acts as an electromagnet and attracts the plunger 3, and 7 is a core that attracts the plunger 3. A spring biases the plunger 3 toward the opposite side of the coil; 8 is an exterior molded resin that covers the above (1) to (7); and 9a, 9b, and 9c are air passages.

Next, the operation will be explained. When current flows from terminal 5 to coil 4, core 6 is excited,
Plunger 3 is attracted to core 6 against spring 7. By sucking the plunger 3 in this manner, the air passages 9b and 9c communicate with each other.

When the current is then turned off, the plunger 3 is pushed back by the restoring force of the spring 7, and the air passages 9a and 9b come into communication. ON/OFF of this current
The air passage is switched by the operation of .

The conventional molded solenoid valve device is constructed as described above, but in this case, the airtightness between the bobbin 1, terminal 5, core 6, and exterior mold resin 8 is incomplete, and the coil 4 generates heat and cools. Due to the breathing action of the coil 4, moisture infiltrates through the joint surfaces of the exterior mold resin 8 and various parts, causing the coil 4 to shorten and break.

[Summary of the idea]

This idea was made to eliminate the drawbacks of the conventional products as described above, and involves coating the joint surfaces of the terminal, core, bobbin, and exterior molding resin with a soft viscous resin material that melts with the heat during exterior molding. This improves the airtightness of the joint and prevents water from entering the coil.

[Example of idea]

An embodiment of this invention will be described below with reference to FIG. In FIG. 2, 1a is a groove provided in the bobbin 1 part that joins with the exterior mold resin 8;
A is a soft viscous resin material coated inside this groove. Further, 10b is a soft viscous resin material coated on the outer surface of the terminal 5, and 10c is a soft viscous resin material coated on the outer surface of the core 6, respectively, to maintain airtightness between the exterior mold resin 8 and each part, that is, the bobbin 1, the terminal 5, and the core 6. ing.

Next, its effect will be explained. In the above-mentioned device, when current flows through the coil 4, the coil generates heat, and the air in the coil portion expands, causing gaps between the exterior mold resin 8 and each part, such as the bobbin 1, terminal 5, and core 6, at the joint surface. However, at this time, the soft viscous resin materials 10a, 10b, 10c coated on these joints
This prevents air leakage and maintains airtightness.

In the above embodiment, an example was shown where the present invention was applied to a molded electromagnetic valve device, but it goes without saying that the present invention can also be applied to other molded products that require waterproofness.

[Effect of idea]

As described above, according to this invention, each joint surface between the exterior mold resin and other assembly parts is coated with a soft viscous resin material to improve airtightness, so it has an extremely simple structure. Therefore, a highly reliable seal structure can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional molded solenoid valve device, and FIG. 2 is a sectional view showing a molded solenoid valve device according to an embodiment of this invention. In the figure, 1 is a bobbin, 1a is a groove, 2 is a plate,
3 is plunger, 4 is coil, 5 is terminal,
6 is a core, 7 is a spring, 8 is an exterior mold resin, 9a, 9b, 9c are air passages, 10a, 1
0b and 10c indicate coated portions of soft viscous resin material. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A soft viscous resin that forms a seal at the joint between the exterior finish molding resin and other assembled parts made of different materials by the molding heat and molding pressure during exterior molding. A seal structure for a molded product characterized by having a coating seal part made of a material. (2) The seal structure according to claim 1 of the utility model registration, characterized in that a groove for preventing outflow is provided in the soft viscous resin coating part.