JP4126557B2 - Solenoid valve device - Google Patents

Description

  The present invention relates to a solenoid valve device.

There is known an electromagnetic valve device in which a fitting hole is formed in a housing made of a magnetic material, and one end in the axial direction of a fixed core is fitted into the fitting hole (for example, see Patent Document 1). FIG. 2 shows an electromagnetic valve device having such a configuration.
In the electromagnetic valve device 200 shown in FIG. 2, a bent portion 204 and a flange member in which one end of a fixed core 206 is press-fitted into a fitting hole 203 formed in the housing 202 and the end portion of the housing 202 is bent outward. 212 is welded. One end of the fitting hole 203 and the fixed core 206 formed in the housing 202 is circular. The outer diameter of one end of the fixed core 206 is larger than the inner diameter of the fitting hole 203 in order to press fit into the fitting hole 203 formed in the housing 202.
JP 2001-304446 A

However, generally, when two metal surfaces are brought into contact with each other with a load, the metals adhere to each other at the contact portion. In particular, the adhesion force due to the same or similar metal tends to increase. Therefore, if the housing 202 and the fixed core 206 are formed of the same or the same kind of magnetic material, a press-fit load (hereinafter simply referred to as a press-fit load) when one end of the fixed core 206 is press-fitted into the fitting hole 203 is increased. If the press-fit load is large, the cylindrical nonmagnetic member 210 may be deformed and the fixed core 206 may move to the movable core 208 side. When the gap between the fixed core 206 and the movable core 208 is reduced by the movement of the fixed core 206, there is a problem that the dynamic characteristics of the valve member 209 that reciprocates together with the movable core 208 varies.
On the other hand, by strictly managing the tolerance between the inner diameter of the fitting hole 203 and the outer diameter of one end of the fixed core 206, the press-fit load can be reduced. However, the processing cost of the housing 202 and the fixed core 206 increases. Since one end of the fixed core 206 is press-fitted into the fitting hole 203, the tolerance between the inner diameter of the fitting hole 203 before the press-fitting and the outer diameter of one end of the fixed core 206 is managed. However, it is not easy to keep the press-fit load at an appropriate size.
In addition, the press-fitting load can be reduced by applying lubricating oil or the like to the side wall 205 of the fitting hole 203 or the side wall 207 at one end of the fixed core 206. However, if the lubricating oil applied to the part to be welded adheres to, for example, a welded part between the housing 202 and the flange member 212, a blowhole is generated at the welded part, so that the welding quality between the housing 202 and the flange member 212 is deteriorated. There is a problem.

  The present invention has been made to solve the above-described problems, and provides an electromagnetic valve device that can easily process a housing and a fixed core and can secure an appropriate interval between the fixed core and the movable core. With the goal.

According to the invention described in claims 1 to 3, since the hardness difference is provided between the side wall of the fitting hole formed in the housing and the side wall of the one end portion of the fixed core, the one end portion of the fixed core is provided in the fitting hole. The adhesive force generated when press-fitting can be reduced. Therefore, the magnitude of the press-fitting load generated when the one end of the fixed core is press-fitted into the fitting hole can be appropriately maintained. Therefore, the thin member is not deformed by the press-fitting load, and the fixed core does not move to the movable core side, so that an appropriate gap can be secured between the fixed core and the movable core. Moreover, since it is not necessary to strictly manage the tolerance between the inner diameter of the fitting hole and the outer diameter of one end of the fixed core, the housing and the fixed core can be easily processed.
According to the third aspect of the present invention, the hardness difference can be provided between the side wall of the fitting hole and the side wall of the one end portion of the fixed core by shot blasting.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a solenoid valve device 10 according to an embodiment of the present invention. The solenoid valve device 10 is used as a fuel metering valve of a high-pressure supply pump for a gasoline cylinder direct injection engine, for example.
The electromagnetic valve device 10 includes a housing 12, a flange member 18, a fixed core 20, a movable core 30, a nonmagnetic member 32, a coil 40, a valve member 50, and a valve body 60. The housing 12, the flange member 18, the fixed core 20, and the movable core 30 are made of a magnetic material and constitute a magnetic circuit.

  The housing 12 is made of a magnetic material such as ferritic stainless steel. The housing 12 has a disc portion 13 and leg portions 16. The disc part 13 has a notch 14 formed on the outer periphery on the side opposite to the position where the leg part 16 is formed. A protrusion 48 of a resin cover 44 described later is fitted in the notch 14. A circular fitting hole 15 is formed at the center of the disc portion 13, and one end side of the fixed core 20 in the axial direction is fitted into the fitting hole 15. The leg portion 16 has an arc shape in cross section and extends from the disc portion 13 to the flange member 18 side at a right angle to the disc portion 13. The end 16a of the leg 16 on the flange member 18 side is in contact with the flange member 18 as a magnetic member.

  The fixed core 20 is formed of the same magnetic material as the housing 12. The fixed core 20 has a small diameter portion 21, a large diameter portion 22, and a small diameter portion 23 in this order from one end side in the axial direction exposed from the fitting hole 15 of the housing 12. The outer diameters of the small-diameter portion 21 and the small-diameter portion 23 are substantially equal and slightly larger than the inner diameter of the fitting hole 15. A small diameter portion 21 as one end portion of the fixed core 20 is press-fitted into the fitting hole 15 of the housing 12, and the fixed core 20 is fitted into the fitting hole 15. Shot blasting is applied to the side wall 21 a of the small diameter portion 21 of the fixed core 20. Therefore, the hardness of the side wall 21a of the small-diameter portion 21 is higher than the hardness of the side wall 15a of the fitting hole 15 due to work hardening accompanying shot blasting.

  The movable core 30 faces the small diameter portion 23 as the other end portion of the fixed core. The nonmagnetic member 32 as a thin portion is formed in a thin cylindrical shape by a nonmagnetic material and covers the periphery of the fixed core 20 and the movable core 30. The nonmagnetic member 32 is sandwiched between the flange member 18 and the small diameter portion 23 side of the large diameter portion 22 of the fixed core 20. The nonmagnetic member 32 prevents the magnetic flux from being short-circuited between the flange member 18 and the fixed core 20. The coil spring 34 biases the movable core 30 in a direction in which the movable core 30 is separated from the fixed core 20, that is, in a direction in which a contact portion 52 of the valve member 50 is separated from a valve seat 62 described later.

The coil 40 is wound around a bobbin 42 and covers the outer periphery of the fixed core 20 and the nonmagnetic member 32. The resin cover 44 covers the coil 40 and the bobbin 42, and a terminal 46 is insert-molded on the resin cover 44. The terminal 46 and the coil 40 are electrically connected.
The valve member 50 is coupled to the movable core 30 and reciprocates together with the movable core 30. The valve member 50 is accommodated in the valve body 60 so as to be reciprocally movable. The contact portion 52 of the valve member 50 can be seated on a valve seat 62 formed on the valve body 60.

  The valve body 60 has an inflow port 64 that opens in the axial direction, and an outflow port 66 that opens in a direction orthogonal to the axis. When the contact portion 52 of the valve member 50 is seated on the valve seat 62, the communication between the inlet 64 and the outlet 66 is blocked. When the contact portion 52 of the valve member 50 is separated from the valve seat 62, the inflow port 64 and the outflow port 66 communicate with each other.

  The stopper plate 70 is assembled to the valve body 60 and defines the lift amount of the valve member 50. A part of the outer peripheral edge portion of the stopper plate 70 is notched, and a communication path 72 is formed by this notch. When the contact portion 52 of the valve member 50 is separated from the valve seat 62, the inflow port 64 and the outflow port 66 communicate with each other through the communication path 72.

When the energization of the coil 40 is interrupted, the contact portion 52 of the valve member 50 is separated from the valve seat 62 by the urging force of the coil spring 34 received in the direction in which the movable core 30 is separated from the fixed core 20. And the outlet 66 communicate with each other via a communication path 72.
When the coil 40 is energized, the movable core 30 is attracted toward the fixed core 20 against the biasing force of the coil spring 34, and the contact portion 52 of the valve member 50 is seated on the valve seat 62. Thereby, the communication between the inflow port 64 and the outflow port 66 is blocked.

Next, the manufacturing process of the electromagnetic valve device 10 will be described.
First, the fixed core 20 is assembled to the nonmagnetic member 32 so that the small diameter portion 23 of the fixed core 20 is fitted into the inner periphery of the nonmagnetic member 32.
Next, the fixed core 20 and the nonmagnetic member 32 are joined to each other at the upper end surface 32a of the nonmagnetic member 32 by welding or the like. The joining location and joining method of the fixed core 20 and the nonmagnetic member 32 are not limited to this. Joining the fixed core 20 and the nonmagnetic member 32 by this step corresponds to “providing a thin member integrally on the outer periphery of the fixed core” recited in the claims.

Next, in a state where the members excluding the nonmagnetic member 32, the resin cover 44, the fixed core 20, and the housing 12 are assembled, the fixed core 20 is fixed to the flange 18 so that the nonmagnetic member 32 is fitted to the outer periphery of the movable core 30. Then, the nonmagnetic member 32 is assembled.
Next, the flange 18 and the nonmagnetic member 32 are joined to each other at the lower end surface 32b of the nonmagnetic member 32 by welding or the like. The joining location and joining method of the flange 18 and the nonmagnetic member 32 are not limited to this.

Next, the resin cover 44 is fitted on the outer periphery of the fixed core 20 and the nonmagnetic member 32.
Next, the end portion of the leg portion 16 is positioned so that the small diameter portion 21 of the fixed core 20 is exposed from the fitting hole 15 of the housing 12 and the protrusion 48 of the resin cover 44 and the notch 14 of the housing 12 are fitted. The housing 12 is pushed in the direction of the fixed core 20 until 16a contacts the flange member 18. As a result, the small diameter portion 21 of the fixed core 20 is press-fitted into the fitting hole 15 of the housing 12. At this time, since the hardness of the side wall 21 a of the small diameter portion 21 is higher than the hardness of the side wall 15 a of the fitting hole 15, the small diameter portion 21 of the fixed core 20 is press-fitted into the fitting hole 15 of the housing 12. The adhesion force that occurs is small.
Next, the housing 12 and the flange member 18 are joined by welding or the like at the end 16a.

In the embodiment of the present invention described above, since the hardness difference is provided between the side wall 15a of the fitting hole 15 of the housing 12 and the side wall 21a of the small diameter part 21, the small diameter part 21 of the fixed core 20 is provided in the fitting hole 15. It is possible to reduce the adhesive force generated when press-fitting. Therefore, the press-fitting load when the small-diameter portion 21 of the fixed core 20 is press-fitted into the fitting hole 15 can be properly maintained. Therefore, the nonmagnetic member 32 is not deformed by the press-fit load, and the fixed core 20 does not move greatly toward the movable core 30, so that an appropriate gap is secured between the fixed core 20 and the movable core 30. be able to. Further, since it is not necessary to strictly manage the tolerance between the inner diameter of the fitting hole 15 and the outer diameter of the small diameter portion 21 of the fixed core 20, the housing 12 and the fixed core 20 can be easily processed.
In one embodiment of the present invention, the side wall 21 a of the small diameter portion 21 of the fixed core 20 is shot blasted so that the hardness of the side wall 21 a of the small diameter portion 21 is the same as that of the side wall 15 a of the fitting hole 15 of the housing 12. By making it higher than the hardness, a hardness difference can be provided between the side wall 15 a of the fitting hole 15 and the side wall 21 a of the small diameter portion 21.

(Other embodiments)
In the above embodiment, the housing 12 and the fixed core 20 have been described as being formed of the same magnetic material, but the same kind of magnetic material may be used. Specifically, for example, the housing 12 and the fixed core 20 may be formed of different ferritic stainless steels.
In the above embodiment, the nonmagnetic member 32 as a thin member is described as being formed of a nonmagnetic material. However, the thin member may be formed of a magnetic material. At that time, the fixed core 20 and the thin member may be integrally formed.

  In the above embodiment, the hardness of the side wall 21a of the small diameter portion 21 of the fixed core 20 has been described as being higher than the hardness of the side wall 15a of the fitting hole 15. The hardness may be higher than the hardness of the side wall 21 a of the small diameter portion 21 of the fixed core 20. At that time, the shot blasting may be performed on the side wall 15a of the fitting hole 15. Further, the housing 12 or the fixed core 20 is subjected to heat treatment or the like to increase the overall hardness of the housing 12 or the fixed core 20, whereby the side wall 21 a of the small diameter portion 21 of the fixed core 20 and the side wall 15 a of the fitting hole 15. And a hardness difference may be provided. Further, a hardness difference may be provided by forming the housing 12 and the fixed core 20 with magnetic materials having different hardnesses.

In the above embodiment, the non-magnetic member 32 is joined to the fixed core 20 and then the fixed core 20 and the non-magnetic member 32 are joined to the flange member 18. However, only the non-magnetic member 32 is joined to the flange member 18. The fixed core 20 may be joined to the flange member 18 and the nonmagnetic member 32 later.
In the above embodiment, the shot blasting process is used to provide a difference in hardness between the side wall 15a of the fitting hole 15 and the side wall 21a of the small-diameter portion 21 of the fixed core 20, but by work hardening accompanying the cutting process. A difference in hardness may be provided, or a difference in hardness may be provided by work hardening accompanying a process of plastically deforming the object to be processed.

It is typical sectional drawing which shows the solenoid valve apparatus by one Embodiment of this invention. It is typical sectional drawing which shows the conventional solenoid valve apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Solenoid valve apparatus, 12 Housing, 15 Fitting hole, 15a Side wall, 18 Flange member (magnetic member), 20 Fixed core, 21 Small diameter part (one end part), 21a Side wall (one side wall), 23 Small diameter part 23 ( Other end), 30 movable core, 32 non-magnetic member (thin member), 40 coil

Claims (3)

A housing;
A fixed core that is press-fitted in an axial end into a fitting hole formed in the housing;
A movable core facing the other axial end of the fixed core;
A magnetic member that covers an outer periphery of the movable core and forms a magnetic circuit with the fixed core, the movable core, and the housing;
Covering the outer periphery of the fixed core and the movable core, and a thin-walled member provided between the fixed core and the magnetic member;
A coil that is installed on the outer peripheral side of the fixed core, the movable core and the thin-walled member, and on the inner peripheral side of the housing, and generates a magnetic force for driving the movable core;
The housing and the fixed core are formed of the same kind of magnetic material,
The solenoid valve device characterized in that the hardness of the side wall of the fitting hole is different from the hardness of the side wall of the one end of the fixed core.   The electromagnetic valve device according to claim 1, wherein the thin member is integrally provided on an outer periphery of the fixed core.   The electromagnetic valve device according to claim 1 or 2, wherein the side wall of the fitting hole or the side wall of the one end portion is subjected to surface processing by shot blasting.

Images