JPS646448Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a solenoid valve that switches fluid passages based on electrical signals.

[Prior art]

Recently, as automobiles and the like are equipped with exhaust gas purification devices, negative pressure has come to be used as a drive source for driving these devices. There is a tendency to often use solenoid valves to switch this negative pressure.

First, the structure of a conventional solenoid valve will be explained based on FIG. Reference numeral 1 denotes a yoke that also serves as a hollow cylindrical case with a bottom, and has a stepped portion 22 on the open end side. Inside the yoke 1, there is a guide 7 which is a solenoid assembly, a bobbin 8, a coil 10, a fixed core 3 having a passage 4 and a seat 5, a spring 12, a groove 14 in the axial direction, and rubber 15 at both ends.
A plunger 13 having a diameter of 16 is covered with an exterior member 9, and is housed together with a spring spacer 6. Here, the yoke 1 and the fixed iron core 3 are magnetically coupled. A side yoke 2 is adjacent to the bobbin 1 and is interposed on the outer circumference of the guide 7 to form a magnetic circuit between the yoke 1 and the movable plunger 13.
17 is passage 19 with seat 18 and passage 2
0 and is adjacent to the bobbin 8. This outer peripheral end is adapted to engage with the stepped portion 22 of the yoke 1. Then, the bobbin 8 bends the spring spacer 6, and in this state, the caulking portion 23 is caulked toward the body 17, and the solenoid assembly including the exterior member 9 is fixed and integrated with the body 17.

In the above, when a current flows from the lead wire 11 to the coil 10, the coil 10 is excited, and when the plunger 13 moves to the left against the spring 12, the sheet 5 and the rubber 16 come into close contact, and the fluid is passed from the passage 20 to the passage 19. It becomes flowing. Next, when the current is cut off, the plunger 13 returns to the right side by the biasing force of the spring 12, the seat 18 and the rubber 15 come into close contact, and the fluid flows from the passage 20 through the groove 14 provided in the plunger 13 to the fixed core 3. The water flows into a passage 4 provided inside.

A solenoid valve with this structure has body 1.
Since the solenoid assembly including the outer member 7 and the outer member 9 was constructed separately, in order to securely hold the solenoid assembly including the outer member 9 to the body 17, the end face of the bobbin 8 on the side opposite to the body 17 side must be A spring spacer 6 had to be interposed between the end face and the yoke 1.

There is no spring spacer, and the bobbin 8 is placed so that the end surface of the bobbin 8 and the bottom of the yoke 1 are in direct contact with each other.
When the bobbin is fixed in the yoke 1, pressure is applied to the bobbin when force is applied to the caulking portion 23.

Since solenoid valves are often used near the engine in the engine compartment of automobiles, the ambient temperature around the solenoid valves is quite high. Furthermore, since current flows through the coil of the solenoid valve intermittently during engine operation, the temperature rise due to the heat generated by the coil is considerable. For example, during a shipping inspection, if the ambient temperature is 100°C and the current is tested, the temperature of the solenoid valve will rise to 150°C. Since the coil bobbin is made of resin, it easily deforms when pressure is applied under such high temperature conditions, causing a problem in which the characteristics of the coil change.

Furthermore, in the first case in which the bobbin is fixed using a spring spacer, the resin softens and expands due to the heat generated by the coil, and the spring spacer bites into the body. When the resin cools and contracts, the spring spacer remains stuck in the resin and softens, creating a gap between the spring spacer and the bottom of the yoke, which may cause the spring spacer to lose its spring function and cause the coil bobbin to become poorly fixed.

[Purpose of invention]

An object of the present invention is to provide a mounting structure that can securely fix a bobbin to a yoke without deforming the body or coil.

[Summary of the idea]

The features of this invention are that the bobbin, side yoke, coil, and the part of the body that is inserted into the yoke are covered and integrated with a synthetic resin exterior member, and a stepped portion extending outward is formed on the outer periphery of this exterior member. By engaging the stepped portion provided on the yoke with the stepped portion and crimping the open end of the yoke to the exterior member, a certain gap is created between the bobbin, the exterior member, and the bottom of the yoke, and the exterior is removed. This is where the member is fixed to the yoke.

[Example of idea]

Next, an embodiment of the present invention will be described based on FIG. 2, where the same reference numerals as in FIG. 1 indicate the same parts.

In Fig. 2, 1 is a hollow cylindrical yoke with a bottom, which is almost the same as the yoke shown in Fig. 1.
This also has a stepped portion 22. Reference numeral 24 designates a body and bobbin (hereinafter referred to as a bobbin-integrated body) in which the body 17 and bobbin 8 shown in FIG. 1 are integrally formed of resin. A coil 10 is wound around the outer periphery of the bobbin portion as in FIG. 1, and a guide 7, a fixed iron core 3, a spring 12, and a plunger 13 are built inside the coil 10. A side yoke 2 is arranged between the bobbin part and the body part of the bobbin-integrated body 24, and these are connected to the exterior member 2.
5 is integrally molded. What should be noted here is that the exterior member 25 has a special shape. That is, the outer periphery of the exterior member 25 has a diameter D that is larger than the diameter d of the exterior portion of the coil 10, as shown in FIG. 3 (state before crimping).
It has a stepped portion 26 extending outwardly. That is, the stepped portion 26 is the stepped portion 22 of the yoke 1.
In this state, the crimping portion 23 of the yoke 1 is crimped to the exterior member 25. As can be understood from FIG. 2 showing the whole in detail, the solenoid valve according to this embodiment has a body and a bobbin integrally molded with resin, and after winding the coil 10 around the bobbin, it is covered with an exterior member 25. In the sheathing process, a stepped portion 26 that is one step higher than the sheath portion of the coil 10 is formed on the sheathing member 25, and then the stepped portion 22 of the yoke 1 and the stepped portion 26 of the sheathing member 25 are engaged to establish a positional relationship. Then, the crimping portion 23 formed at the open end portion of the yoke 1 is bent inward of the exterior member 25 and crimped.

With this structure, the bobbin and the body are integrally formed, and the stepped portion 22 of the yoke 1 engages with the stepped portion 26 provided on the exterior member 25 that is exteriorized around the bobbin-integrated body 24. Since the bobbin body is crimped by the yoke, the bobbin-integrated body can be fixed to the yoke while leaving a gap between the yoke bottom, the bobbin, and the exterior member. Therefore, no pressure is applied to the coil during tightening. Furthermore, even if the temperature rises and the resin of the coil bobbin expands, there is no risk of the coil bobbin deforming because there is a gap.

Next, a second embodiment of the present invention will be explained based on FIG.

The embodiment shown in FIG. 4 shows a case where the bobbin and the bobbin are not integrally formed of resin as in the embodiment shown in FIG. 2, but are formed separately. That is, the bobbin 8 and the body 17 are formed separately as shown in FIG. 1, and the side yoke 2 is disposed between them.
The bobbin 8, side yoke 2, and body 17 are integrated by an exterior member 25. At this time, a stepped portion 26 extending outward as shown in FIG. 3 is formed in the middle of the exterior member 25. The stepped portion 22 of the yoke 1 engages with this stepped portion 26, as shown in FIG. 3, to maintain the positional relationship between the yoke 1 and the exterior member 25. After that, the caulking portion 23 provided at the open end portion of the yoke 1 is attached to the exterior member 25.
Bend inward and tighten, yoke 1 and exterior member 25
It integrates the

In this way, even in the embodiment shown in Fig. 4, the bobbin-integrated body can be fixed to the yoke while leaving a gap between the yoke bottom, the bobbin, and the exterior member, and the bobbin can be securely fixed to the yoke without deforming the coil. We can provide a suitable mounting structure.

Also in this embodiment, since a spring spacer is not required, costs can be reduced.

In addition, since the conventional separate bobbin and body are used as is, current production equipment can be used as is.
It can be manufactured by simply changing the mold for the exterior member.

[Effect of idea]

As described above, according to the present invention, the bobbin-integrated body, which integrates the bobbin, side yoke, body, and mounting member, can be fixed to the yoke by caulking while leaving a gap between the yoke bottom, the bobbin, and the exterior member. Therefore, no pressure is applied to the coil during tightening. Furthermore, even when the resin expands due to temperature rise, the coil bobbin does not deform due to the gap. Therefore, the coil bobbin can be reliably fixed to the yoke without deforming the coil bobbin and the coil.

Further, according to the present invention, since a spring spacer is not used, it is possible to reduce costs by reducing the number of parts.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a conventional solenoid valve. FIG. 2 is a longitudinal sectional view of a solenoid valve according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing an enlarged cross-section of the main part of FIG. 2 and before crimping. FIG. 4 is a longitudinal sectional view of a solenoid valve according to another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Yoke, 10... Coil, 24... Bobbin integrated body, 22... Stepped part, 23... Caulking part, 26... Stepped part.

Claims (1)

[Scope of utility model registration request] Synthetic resin body with internal fluid passages,
a synthetic resin bobbin adjacent to the body and having a fixed iron core inside and a plunger for opening and closing the fluid passage; a coil wound around the outer periphery of the bobbin;
A solenoid valve comprising a yoke that is magnetically coupled to the fixed iron core and covers the coil, and a side yoke that is magnetically coupled to the yoke and located between the body and the bobbin, the bobbin, the side yoke, and the bobbin. The coil and the portion of the body to be inserted into the yoke are integrated by covering with an exterior member made of synthetic resin, and a stepped portion extending outward is formed on the outer periphery of the exterior member, and a stepped portion is formed on the inner wall of the opening side of the yoke. forming a stepped part;
engaging the stepped portion and the stepped portion and crimping the open end of the yoke to the exterior member on the body side;
A solenoid valve characterized in that the exterior member is fixed with a certain gap between the bobbin and the exterior member and the bottom of the yoke.