JPH0441481B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a solenoid for an electromagnetic valve, and more specifically, to a method of manufacturing a solenoid with excellent airtightness.

As shown in FIG. 1, this type of electromagnetic valve solenoid has a pole 2 fitted in the bottom 1a of a yoke 1 having a bottomed cylindrical shape. The sleeve 4 is fitted,
Further, a bobbin 6 wound with a coil 5 having a wire diameter of about 0.2φ is inserted into the outer periphery of the sleeve 4, and the base 10 is connected to the groove through a packing 7, an end yoke 8, and an O-ring 9. The yoke 1 is integrated by fitting the open end 1b of the yoke 1 into the yoke 10a. Further, a plunger 11 is fitted into the inner periphery of the sleeve 4 so as to face the pole 2, and the base 1
A valve rod 12 is inserted through the valve 0 and the plunger 11. A flange 12a formed on the valve stem 12 engages with a stepped portion 11a of the plunger 11, and a spring 13 is interposed between the flange 12a of the valve stem 12 and the pawl 2, so that the plunger 11 and the valve stem 12
is biased toward the opposite pole 2 side. Then, by energizing the coil 5, the plunger 11 is attracted and at the same time the valve stem 12 is moved in the direction of the pole 2, thereby opening a fluid flow path (not shown).

The coil 5 is energized through the lead wires 14, and as shown in FIG. 2, the coil terminals 5a drawn out from the bobbin 6 are connected to the lead wires 14, respectively. The lead wire 14 is drawn out from the yoke 1 through a rubber grommet 15, as shown in FIG.

However, depending on the installation location, water may enter the lead wire 14 from the lead-out portion or the open end 1b of the yoke 1, and the entered water may reach the coil 5.
If there is a pinhole in the coil 5, this will cause electrolytic corrosion and cause the coil 5 to be disconnected. Therefore, in order to prevent water from entering between the coils 5,
The coil terminal 5a and the lead wire 14, which are particularly prone to electrolytic corrosion, are separated from each other by a partition wall 6a as shown in FIG. An adhesive 16 was applied to water intrusion parts such as the drawer part 14a of the yoke 14 and the open end 1a of the yoke 1.

However, the varnish treatment requires a lot of time for heating and drying, and since the adhesive 16 is applied by hand with a brush, there are many variations and the reliability is lacking.

In view of the above problems, the present invention provides a method for manufacturing a solenoid for a solenoid valve that is simple and has excellent airtightness.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 shows a solenoid for an electromagnetic valve obtained by the method of the present invention, in which the same members as in the conventional example are given the same reference numerals. The difference from the conventional solenoid is that adhesive is not applied to the lead-out portion 14a of the lead wire 14 and the open end 1a of the yoke 1 of the solenoid according to the present invention, and the inside of the yoke 1 is filled with a filler 17. This is because a space 18 is formed within the yoke 1 on the opposite side from the lead-out portion 14a of the lead wire 14. And this filler 17
As a result, the lead wire 14 can prevent water from entering through the lead-out portion 14a and the open end 1a of the yoke 1, and it is possible to eliminate disconnection of the coil due to electrolytic corrosion.

Next, a manufacturing method according to the present invention will be explained. Fifth
The figure shows the product in the middle of manufacturing, with the pole 2, bobbin 6, plunger 11, etc. being assembled, before the base 10 is assembled. In this state, the filler 17 is injected into the gap within the yoke 1 in the present invention. Thereafter, as shown in FIG. 6, the gasket 7, end yoke 8, O-ring 9, and base 10 are assembled, and the open end 1a of the yoke 1 is fitted and fixed in the groove 10a of the base 10. Then, the integrated solenoid is turned over and left with the base 10 facing down. Subsequently, the filler 17 is lowered and the lead wire 14
The resin is cured so as to cover the outer periphery of the pull-out portion 14a and the end yoke 8. At this time, the filler 17 is applied at least to the lead wire 14 in the lead-out portion 14a.
It is sufficient to cover the fitting portion of the outer periphery of the end yoke 8 that communicates from the open end 1a of the yoke 1 with the inner periphery of the yoke 1, and there is no need to strictly control the filling amount, so automation is possible.

As described above, the method for manufacturing a solenoid for an electromagnetic valve according to the present invention involves injecting the filler into the gap inside the yoke, then fitting the base into the injected opening, and turning it upside down so that the base is on the lower side. This allows filling and fixing only the areas that are prone to water intrusion (the yoke and base fittings, and the lead wire pull-out area), which ensures a perfect seal and prevents the coil from breaking due to electrolytic corrosion, while also reducing the amount of filler. This makes it easier to manage the filling amount.

Furthermore, a space is formed on the side of the yoke opposite to the base due to the fall of the filler, and the center of gravity of the solenoid valve can be brought closer to the base, making it possible to improve vibration resistance in the installed state.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional solenoid.
FIG. 2 is a perspective view of a bobbin used in a solenoid. FIG. 3 is an external view of a conventional solenoid. FIG. 4 is a partial sectional view of the solenoid in the present invention. FIG. 5 and FIG. 6 are explanatory views of filling the filler in the present invention. Explanation of symbols, 1...Yoke, 10...Base,
17...Filler, 18...Space.

Claims (1)

[Claims] 1. A cylindrical yoke with a bottom, a pole fixed to the bottom of the yoke, a sleeve arranged around the outer periphery of the pole via an O-ring, a coil bobbin arranged around the outer periphery of the sleeve, a coil wound around the coil bobbin,
A lead wire with one end connected to the coil and pulled out through a grommet on the open side of the yoke, a base fixed by closing the opening of the yoke and fitting the open end of the yoke, between the base and the coil bobbin In a solenoid for a solenoid valve, the solenoid is equipped with a packing and an end yoke, a plunger provided inside the sleeve, and a filler filled in the gap inside the yoke. Coil bobbin wound with
After assembling the lead wires and injecting the filler into the gap inside the yoke, place the packing and end yoke and fit the base, then turn the base downwards (upside down) and lower the filler. A method of manufacturing a solenoid for a solenoid valve, which is characterized by hardening the solenoid.