JP3323925B2 - Manufacturing method of solenoid valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a solenoid valve for controlling opening and closing of a fluid passage.

[0002]

2. Description of the Related Art In a solenoid valve, a valve body in which a ball is fixed to a tip of a plunger for controlling opening and closing of a valve is used. Various methods have been proposed for this fixing. For example, a method of forming a hemispherical recess slightly smaller than the ball valve body at the tip of the plunger and fitting the ball valve body into the recess by elastic pressure, forming a hemispherical recess at the tip of the plunger, and forming the inner surface of the recess , And a ball valve element is fitted and fixed. However, in the former method, an excessive load acts on the tip of the plunger at the time of fitting, and there is a fear that cracks or breakage may occur, and it is difficult to make close contact with the inner surface of the recess. Further, in the latter method, there is a fear that the adhesive may peel off or melt and the ball valve body may be separated due to an impact acting on the valve body when the valve is opened or closed or a rise in temperature during the passage of the hot fluid.

[0003]

SUMMARY OF THE INVENTION The present invention solves these problems of the prior art, and provides a method of manufacturing a solenoid valve capable of securely fixing a ball valve body at the tip of a plunger without forming a gap. The purpose is to:

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide an armature core fixed to the inner periphery of an armature coil, and the armature core being energized by the electric coil to excite the armature core. a plunger to move in the axial direction to open and close control the flow path of the fluid, the ball at the tip of the plunger of the solenoid valve having a ball valve body which is fixed to the tip of the plunger
Slightly to form a recessed portion of the hemispherical diameter smaller than Lumpur valve body, the
The ball valve body is brought into contact only with the entire periphery of the recess on the opening side.
In this state, it is fitted into the recess, and the recess is
The entire peripheral edge of the opening side is melted and the ball valve body is moved forward.
The present invention is achieved by a method for manufacturing a solenoid valve, wherein the solenoid valve is pressed into the recess and fixed to the recess .

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing one embodiment of a solenoid valve. The solenoid valve 10 includes a housing 12 that covers the whole, and the housing 12 is provided with openings 12a and 12b for opening a passage of a valve seat member described below on the side wall and the upper wall of the housing, respectively. Have been.

The solenoid valve 10 includes a valve body 14 made of a cylindrical magnetic metal, an electromagnetic coil 15 housed in the valve body, an armature core 16 held inside the electromagnetic coil, and a housing. A valve seat member 17 is disposed and held on the upper part of the armature 12, and a plunger 18 is slidably inserted between the armature core 16 and the valve seat member 17.

[0007] The electromagnetic coil 15 is held by a holding member 19, and a wire connector 20 protrudes outward from the lower end of the holding member 19 in the radial direction. The armature core 16 has a large-diameter lower portion 16a press-fitted into the housing 12 and fixed thereto, and an upper portion 16b of which has a smaller diameter to form an electromagnetic coil 15a.
Extends into. An axial passage 21 is formed in the valve seat member 17 along the central axis, the upper end thereof communicates with the outside through the opening 12b, and the lower end surface is a concave valve seat 22 along the spherical surface of the ball valve body 24. I have. On the lower surface of the valve seat member 17,
A groove extending in the radial direction is provided to form a radial passage 25 that connects the opening 12 a and the passage 21. The plunger 18 is integrally formed in a substantially cylindrical shape, and has a fitting recess 2 at an upper end.
3 are formed. In the fitting recess 23, the valve seat 2 is provided.
2 , a steel ball valve body 42 for opening and closing the passage 21 away from
Is fixed. Further, the ball valve element 2 is resiliently connected to the upper end surface of the armature core 16 inserted into the cylindrical hole 18a extending into the plunger 18 by the elastic force of the spring 26.
4 is urged in a direction to close the passage 21.

[0008] The plunger 18, sintered metal, may be any of the general bulk metal, the curvature of the fitting recess 23 and a half
The diameter is smaller than the diameter of the ball valve element 24, as shown in FIG.
To reduce the melting near the fitting recess 23.
Satisfactorily close contact with the ball valve element 24 can be obtained.
ing. When using a sintered metal, for example, the fitting recess 2
3 is 3 mm, and the diameter of the ball valve 24 is 4 mm.
Can be.

The connection between the fitting recess 23 of the plunger 18 and the ball valve body 24 is performed as follows. First, the ball valve element 24 is loosely fitted into the fitting recess 23 (FIG. 2). Thereafter, resistance welding is performed. The fitting recess 23 is formed by this resistance welding.
The peripheral wall melts and joins the ball valve element 24. At this time, no gap is formed between the fitting recess 23 and the lower half of the ball valve element 24, and the fitting recess 23 is kept in contact with the entire inner peripheral surface (FIG. 3).

The ball valve body 24 may be made of ceramics instead of steel. In this case, if the plunger is a sintered metal, weight reduction is further promoted, so that the inertial force due to the valve operation is reduced, and the open / close response of the small-diameter passage can be improved.

[0011]

In the solenoid valve according to the method of the present invention, after the ball valve is fitted into the fitting recess at the tip of the plunger, the ball valve is fixed by resistance welding. Therefore, no impulsive load is applied when the plunger is fixed to the plunger, and no crack or breakage occurs. In addition, since the plunger tip is fixed by melting, the ball valve body can be tightly joined without forming a gap in the inner peripheral surface of the fitting recess. Also, at the tip of the plunger,
A hemispherical recess with a slightly smaller diameter than the
The ball valve body is brought into contact only with the entire periphery of the recess on the opening side.
In this state, it is fitted into the recess, and the recess is
The entire peripheral edge of the opening side is melted and the ball valve body is moved forward.
The ball valve is pressed into the recess and fixed to the recess.
Is evenly distributed by the entire periphery of the recess on the opening side.
Will be retained, and before the resistance welding,
The ball valve element can be reliably positioned in the recess.
Wear. And by performing resistance welding in this state,
The opening peripheral wall of the recess can be melted uniformly.
You. In this way, the positioning of the ball valve element is ensured.
The entire peripheral wall on the opening side of the recess by resistance welding
Can be melted uniformly, so that the plunge
The ball valve element is plunged by the melting of the recess of the plunger.
The ball valve can be prevented from being accidentally shifted from the shaft.
It can be accurately fixed to the recess. Moreover, the above
There is no need to operate to prevent the ball valve from shifting,
Easy fixing of the ball valve body to the plunger recess
Can be done.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a solenoid valve structure according to the present invention.

FIG. 2 is a longitudinal sectional view showing a state before a ball valve body is resistance-welded to a fitting recess of a plunger made of a sintered metal.

FIG. 3 is a longitudinal sectional view showing a state in which the ball valve element shown in FIG. 2 is fixed in a fitting recess by resistance welding.

[Explanation of symbols]

 Reference Signs List 10 solenoid valve 15 solenoid coil 16 armature core 18 plunger 23 fitting recess 24 ball valve

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-145268 (JP, A) JP-A-58-5570 (JP, A) JP-A-5-193492 (JP, A) 7374 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16K 31/06-31/11 B23K 11/00 B23K 11/02

Claims (1)

(57) [Claims] 1. An armature core fixed to the inner periphery of an armature coil, and the armature core is excited by the armature coil to move in the axial direction of the armature core to open and close a fluid flow path. a plunger for controlling, the plunger slightly from the tip to the ball valve element of the plunger of the solenoid valve with anchored a ball valve element to the distal end of a recess of hemispherical small, the ball valve The body around the opening side of the recess
It is fitted into the recess with only the edge in contact with it, and the entire periphery on the opening side of the recess is melted by resistance welding , and
A method for manufacturing a solenoid valve, wherein the ball valve body is pushed into the recess and fixed to the recess .