JP2532761B2 - Solenoid assembly method - 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 assembling a solenoid, and more particularly to a method for assembling a solenoid that achieves a high degree of perpendicularity between a suction surface of a fixed iron core and an axis of a movable iron core.

[0002]

2. Description of the Related Art A solenoid has been conventionally provided in which a magnetic flange member is fitted in one end of an annular coil and a movable iron core is movably guided inside the magnetic flange member. An example of such a conventional solenoid is disclosed in Japanese Utility Model Publication No. 61-16664. In the solenoid described in this publication, the fixed iron core is fitted into one end of the hole of the coil bobbin in the axial hole formed in one part of the magnetic frame arranged so as to surround the coil. The cylindrical portion of the magnetic flange member is fixed to one portion of the magnetic frame, and the cylindrical portion of the magnetic flange member is fitted into the shaft hole formed in the other portion of the magnetic frame and the other end of the hole of the coil bobbin. Is to guide the movable iron core.

However, in a solenoid using such a conventional magnetic flange member, in order to reduce the magnetic resistance between the magnetic frame member and the magnetic flange member, the flange portion of the magnetic flange member and the other portion of the magnetic frame member are reduced. Despite the close contact with the surface, because the magnetic frame is bent by pressing, one part and the other part are not always exactly parallel to each other. The fixed iron core fitted in the hole of the coil bobbin does not always have parallelism with the attraction surface, and the orthogonality between the attraction surface and the axis of the movable iron core guided by the tubular portion cannot be ensured. As a result, there is a problem that the attraction surface of the fixed iron core and the corresponding attraction surface of the movable iron core are inclined and noise is generated during attraction.

[0004]

The problem to be solved by the present invention is to fit a fixed iron core in one end of a hole of a coil bobbin and a magnetic flange member in the other end, and In a method of assembling a solenoid in which a movable iron core is guided by a tubular portion, it is possible to accurately obtain the right angle between the attraction surface of the fixed iron core and the axis of the movable iron core.

[0005]

According to the present invention, a fixed iron core is fitted in one end of a hole of a coil bobbin and an axial hole of a magnetic frame surrounding the coil bobbin, and the other end of the hole of the coil bobbin and the magnetic frame. In a method for assembling a solenoid in which a magnetic flange member is fitted in an axial hole, a fixed iron core is fitted in one end of the hole of the coil bobbin and in the axial hole of the magnetic frame, and the surface of the magnetic frame and the magnetic An elastic member is interposed between the flange member and the tubular portion of the magnetic flange member is fitted into the other end of the hole of the coil bobbin and the shaft hole of the magnetic frame to form a temporary assembly of the solenoid, The temporary assembly is inserted into a mold, and the magnetic flange member is provided in the tubular portion with the attraction surface of the fixed iron core and the inner surface of the tubular portion in contact with each other so that the attraction surface and the axial center of the tubular portion. Insert a core member that ensures a high degree of right angle Is to inject a resin material and integrally combine the coil bobbin, the magnetic frame, the fixed iron core and the magnetic flange member with the resin material, and then insert the movable iron core movably into the cylindrical portion of the magnetic flange member. It is configured.

[0006]

In the above structure, the magnetic flange member is positioned with respect to the fixed iron core such that its axis is perpendicular to the attracting surface of the fixed iron core, the coil bobbin, the fixed iron core,
Since the magnetic frame and the magnetic flange member are integrally joined by the resin material, the perpendicularity between the axis of the movable iron core guided by the cylindrical portion of the magnetic flange and the attraction surface of the fixed iron core is almost completely ensured. Therefore, the parallelism between the attraction surface of the fixed iron core and the attraction surface of the movable iron core is ensured. As a result, no great noise is generated even when the movable core is attracted to the fixed core during the operation of the solenoid.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a solenoid 1 assembled by the assembly method of the present invention is shown in cross section. In the figure, 2 is a coil bobbin, 3 is a coil winding wound around the body 21 of the coil bobbin 2, 4 is a magnetic frame surrounding the coil bobbin, 5 is one end of the hole 22 of the coil bobbin 2 and the axis of the magnetic frame 4. A fixed iron core fitted in the hole 41, 6 in the other end of the hole 22 of the coil bobbin and the shaft hole 42 of the magnetic frame 4.
A magnetic flange member fitted therein, 7 a movable iron core guided by the magnetic flange member 6, and 8 an elastic member.

When assembling such a solenoid,
As shown in FIG. 2A, the fixed iron core 5 is located at one end (upper end in the figure) of the hole 22 of the coil bobbin 2 in which the coil winding 3 is provided on the outer periphery of the body portion 21 and the small diameter portion 51 thereof is hidden. After the insertion, the elastic member 8 is attached to the cylindrical portion of the magnetic flange member 6 in the other end (lower end in the figure) of the hole 22 of the coil bobbin 2 and the cylindrical portion of the magnetic flange member is inserted.

Next, the magnetic frame 4 is assembled so that the elastic member 8 is sandwiched between the lower surface 43 of the magnetic frame 4 and the magnetic flange member 6, and the small diameter portion 51 of the fixed iron core 5 is attached to the magnetic frame 4. 2 is pushed out so as to fit into the shaft hole 41, and the tip of the small diameter portion 51 is caulked to fix the fixed iron core to the magnetic frame.
Make a solenoid temporary assembly as shown in [A].

The temporary assembly produced as described above is
As shown in FIG. 2 [B], it is put into the mold a. As is clear from the figure, the mold a includes a lower mold b that defines a molding chamber c, and an upper mold d that is placed on the lower mold b and that defines the molding chamber c. A mandrel e is arranged in the molding chamber c of the lower mold b. The mandrel e is fixed to the bottom wall f of the lower mold b. The outer diameter of the mandrel e is such that it fits snugly in the cylindrical portion 62 of the magnetic flange member 6 without play. The mandrel e is formed such that the axis 0-0 of the mandrel e and the upper end surface g thereof are exactly at right angles. The distance from the inner surface of the bottom wall f of the lower die b to the upper end surface g of the mandrel e is such that the elastic member 8 is slightly compressed when the attracting surface 52 of the fixed iron core 5 contacts the upper end surface g of the mandrel e. In this state, the lower surface of the flange portion 61 of the magnetic flange member 6 (in FIG. 2 [B]) contacts the inner surface of the bottom wall f of the lower mold b. The upper die d is provided with a rod h that comes into contact with the end surface of the small diameter portion 51 of the fixed iron core 5 and pushes down the entire temporary assembly so as to be vertically movable, and is pressed downward by a spring j.

When the temporary assembly is thus positioned in the molding chamber c of the molding die a, the cylindrical portion 62 of the magnetic flange member 6 has the shaft hole 42 of the magnetic frame 4 and the coil bobbin 2.
Since the elastic member 8 is fitted in the hole 22 of the magnetic frame 4 and the elastic member 8 exists between the surface 43 of the magnetic frame 4 and the flange portion 61, almost the entire attracting surface 52 of the fixed iron core 5 contacts the upper end surface g of the mandrel e. And substantially the entire lower surface of the flange 61 is the bottom wall f of the lower mold b.
Stable in contact with the inner surface of the. Under such a condition, as shown in FIG. 2C, the injection port i of the mold a is
The resin material is injected into the molding chamber c. Then, the resin material 9 fills the gap in the molding chamber, and integrally fixes the coil bobbin 2, the magnetic frame 4, the fixed iron core 5, the magnetic flange member 6, and the elastic member 8.

After taking out the one integrally molded with the resin material as described above from the molding die a, the movable iron core 7 is placed in the cylindrical portion 62 of the magnetic flange member 6 as shown in FIG.
Is movably inserted to complete the solenoid assembly. In FIG. 1, 10 is a solenoid valve 1 together with a solenoid 1.
00 is a main body, 11 is a valve body made of an elastic material embedded in the lower surface of the movable iron core 7, 12 and 13 are ports formed in the main body 10, 14 is a valve seat formed in the main body, Reference numeral 15 is a spring that elastically presses the movable iron core 7 downward.
The elastic member may be a ring-shaped member made of rubber or the like, or a washer made of a magnetic material having a cross section as shown by 8a in FIG.

[0013]

According to the present invention, since the perpendicularity between the attraction surface of the fixed iron core and the axis of the movable iron core can be accurately ensured, the attraction surface of the fixed iron core and the attraction surface of the movable iron core are made uniform over the entire surface. It is possible to bring them into contact with each other, and noise during operation of the solenoid can be reduced. Further, it is possible to prevent the resin material from flowing onto the surface of the flange portion of the magnetic flange member during molding. Furthermore, in the case of assembling by the conventional method, the inner diameter of the tubular portion of the flange member is set to prevent uneven wear of the movable core and the flange member due to an incorrect squareness between the axis of the flange member and the attraction surface of the fixed iron core. On the other hand, it is necessary to reduce the outer diameter of the movable iron core in advance, which causes a problem that the gap between the flange member and the movable iron core becomes large and the magnetic efficiency is reduced. Since there is no magnetic field, it is possible to increase the magnetic efficiency.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a solenoid made from the present invention.

FIG. 2 is a diagram showing a method of assembling the solenoid of the present invention.

FIG. 3 is a diagram showing a modified example of an elastic member.

[Explanation of symbols]

 1 Solenoid 2 Coil bobbin 22 Hole 3 Coil winding 4 Magnetic frame 41, 42 Shaft hole 5 Fixed iron core 52 Adsorption surface 6 Magnetic flange member 61 Flange portion 62 Cylindrical portion 7 Movable iron core 8, 8a Elastic material 9 Resin material

Claims (1)

(57) [Claims] 1. A fixed iron core is fitted in one end of a hole of a coil bobbin and in a shaft hole of a magnetic frame surrounding the coil bobbin, and a magnetic flange member is provided in the other end of the hole of the coil bobbin and the shaft hole of the magnetic frame. In a method of assembling a solenoid by fitting, a fixed iron core is fitted into one end of the hole of the coil bobbin and the shaft hole of the magnetic frame, and an elastic member is provided between the surface of the magnetic frame and the magnetic flange member. And the cylindrical portion of the magnetic flange member is fitted into the other end of the hole of the coil bobbin and the shaft hole of the magnetic frame to form a temporary assembly of the solenoid. A core that is inserted into the magnetic flange member and contacts the attraction surface of the fixed iron core and the inner surface of the cylinder portion inside the cylinder portion to ensure a high degree of perpendicularity between the attraction surface and the axis of the cylinder portion. Insert the member and inject the resin material into the mold Depending on the material, the coil bobbin, magnetic frame,
A method for assembling a solenoid, characterized in that a fixed iron core and a magnetic flange member are integrally connected, and then a movable iron core is movably inserted into a cylindrical portion of the magnetic flange member.