JP2009162316A - Solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solenoid valve, capable of achieving prescribed attraction force by restricting coaxiality error between a plunger and an outer yoke so as to reduce diametric error of an attraction part. <P>SOLUTION: The outer yoke 14 and the plunger 12 are enclosed by the inner circumference of a third hole 10c of a valve body 10. The plunger 12 is disposed between the outer yoke 14 and a spool 11. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a solenoid valve.

  As a conventional solenoid valve, one disclosed in Patent Document 1 is known. This solenoid valve includes a plunger, a front yoke, a rear yoke, a shaft, a bearing, a bobbin, and the like.

  A cylindrical front yoke having a flange portion is built in the inner peripheral side of the bobbin around which the coil is wound. A ring-shaped rear yoke is press-fitted into one end of the front yoke, and the bobbin is held between the flange portion of the front yoke and the rear yoke.

  The front yoke has a through hole at the center, and bearings are disposed at both ends thereof, and holds the shaft and the plunger press-fitted into the shaft so as to be slidable in the axial direction.

Moreover, the solenoid valve shown by patent document 1 comprises the attraction | suction part with the plunger and the rear yoke.
JP 2007-92768 A

  However, in the invention of Patent Document 1, there are a large number of component parts that determine the positional relationship between the plunger and the rear yoke that constitute the suction part of the solenoid valve. The radial error tends to increase. For example, the radial gap between the outer peripheral surface of the shaft and the inner peripheral surface of the bearing, the coaxiality error between the outer peripheral surface of the bearing and the inner peripheral surface of the front yoke, the outer peripheral surface of the front yoke and the inner peripheral surface of the rear yoke There is a coaxiality error. The errors generated by the processing accuracy at the time of manufacturing each component exemplified above are accumulated, and as a result, errors in the radial direction of the suction portion between the plunger and the rear yoke are increased, and there is a possibility that a predetermined suction force cannot be exhibited. It was.

  The present invention has been made in view of the above problems, and its purpose is to reduce the error in the radial direction of the suction portion by minimizing the accumulation of dimensional errors with a smaller number of parts than in the past. An object of the present invention is to provide a solenoid valve capable of exerting a suction force.

In order to solve the above technical problem, the first technical means taken in the present invention is:
A valve body in which a fluid passage is formed;
An inner yoke made of a magnetic material;
A cylindrical bobbin disposed around the inner yoke and wound with a coil;
A cylindrical outer yoke made of a magnetic material disposed on the outer peripheral side of the bobbin and fixed to the inner yoke;
A cylindrical plunger that is disposed on the outer peripheral side of the bobbin and is made of a magnetic material that is movable in one axial direction of the bobbin by energizing the coil;
A valve member disposed in the valve body so as to be able to open and close the fluid passage, and movable with the plunger;
A solenoid valve comprising a biasing member that biases the plunger and the valve member toward the other axial direction of the bobbin.

The second technical means is the first technical means,
The outer yoke and the plunger are held by the inner periphery of the valve body.

The third technical means is the first technical means or the second technical means,
The plunger is disposed between the outer yoke and the valve member.

The fourth technical means is the third technical means,
A stopper provided on one end of the valve member and having a flange;
The plunger has a cylindrical shape with a through hole formed at the end on the valve member side,
The valve member is inserted into the through hole of the plunger so that the flange and the end of the plunger on the valve member side are engaged, and a gap is formed between the plunger and the valve member. It has been done.

The fifth technical means is the second technical means to the fourth technical means,
An adjustment mechanism for adjusting the axial position of the outer yoke is formed on the outer peripheral surface of the outer yoke and the inner peripheral surface of the valve body.

The sixth technical means is the fourth technical means,
The adjustment mechanism includes a male screw formed on the outer peripheral surface of the outer yoke and a female screw formed on the inner peripheral surface of the valve body.

  According to the first aspect of the present invention, since the outer yoke and the plunger are arranged on the outer peripheral side from the bobbin, even if there is an error caused by processing accuracy of each component other than the outer yoke and the plunger, It does not affect the positioning of the outer yoke and plunger. Therefore, it is possible to suppress a coaxiality error between the plunger and the outer yoke and reduce a radial error of the suction portion, and to exhibit a predetermined suction force.

  According to the second aspect of the present invention, the outer yoke and the plunger are held by the inner periphery of the valve body, so that the suction portion between the outer yoke and the plunger is held by the valve body. Therefore, the position of the suction portion can be determined only by the inner periphery of the valve body, the outer periphery of the outer yoke, and the outer periphery of the plunger. Therefore, it is possible to suppress a coaxiality error between the plunger and the outer yoke and reduce a radial error of the suction portion, and to exhibit a predetermined suction force.

  According to the third aspect of the present invention, since the plunger is disposed between the outer yoke and the valve member, it is not necessary to use a shaft and a bearing that are conventionally required. Therefore, there is no radial gap between the outer peripheral surface of the shaft and the inner peripheral surface of the bearing, and the error in the radial direction of the suction portion is reduced by suppressing the coaxiality error between the plunger and the outer yoke as compared with the conventional case. Can demonstrate power.

  Further, according to the invention of claim 3, since it is not necessary to use the shaft and the bearing which are conventionally required, the number of parts can be reduced and a low-cost solenoid valve can be formed.

  According to the invention of claim 4, the valve member is inserted into the through hole of the plunger so that the flange portion and the end of the plunger on the valve member side are engaged, and a gap is formed between the plunger and the valve member. Accordingly, even if there is a coaxiality error between the solenoid valve insertion hole formed in the valve body and the solenoid valve, the coaxiality error between the valve member and the plunger can be allowed. Therefore, the valve member can be smoothly slid.

  According to the invention of claim 5, since the adjustment mechanism for adjusting the axial position of the outer yoke is formed on the outer peripheral surface of the outer yoke and the inner peripheral surface of the valve body, the dimensional error in the axial direction of each component is reduced. Even if it becomes larger, the axial position of the outer yoke can be accurately fixed.

  According to the invention of claim 6, the adjustment mechanism can be formed by simple processing by having the male screw formed on the outer peripheral surface of the outer yoke and the female screw formed on the inner peripheral surface of the valve body. Become.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2.

  A coil 15 is wound around a bobbin 16 made of a resin material. The coil 15 is electrically connected to the terminal 17 from one end. The terminal 17 is disposed in the connector holder 18 and is electrically connected to a power source (not shown) via an external connector (not shown).

  The connector portion 23 made of a resin material has an inner yoke 13, a coil 15, a bobbin 16, and a terminal 17, which will be described later, integrally molded and a connector holder 18 formed at one end.

  The inner yoke 13 made of a magnetic material is disposed on the inner peripheral side of the bobbin 16 and has a cylindrical shape. At one end, a thick first flange 13b is formed, and a thin second rib 13c having a larger outer diameter than the first flange 13b is formed. When the inner yoke 13, the coil 15, the bobbin 16, and the terminal 17 are molded into the second flange portion 13 c, the resin of the connector portion 23 wraps around. A hole 13 a is formed at the other end of the inner yoke 13.

  The outer yoke 14 made of a magnetic material is disposed on the outer peripheral side of the bobbin 16, has a cylindrical shape, and is press-fitted into the first flange 13 b of the inner yoke 13. At one end thereof, an annular outer yoke-side front end portion 14a is formed in which the outer peripheral surface is notched obliquely with respect to the axial direction and is thinned one step. A male screw constituting the adjustment screw 22 is formed on the outer peripheral surface of the other end of the outer yoke 14.

  The plunger 12 made of a magnetic material is disposed on the outer peripheral side of the bobbin 16 so as to face the outer yoke 14 and has a cylindrical shape having a bottom portion. The bottom side (left side in FIG. 1) is one step thinner, and a through hole 12b is formed in the bottom. The opening end side is formed with an annular plunger-side tip portion 12a whose inner peripheral surface is notched obliquely with respect to the axial direction and is thinned by one step. The plunger-side tip portion 12 a has an inner diameter that is slightly larger than the outer diameter of the outer yoke-side tip portion 14 a of the outer yoke 14.

  The plunger-side tip portion 12a and the outer yoke-side tip portion 14a constitute a suction portion in a shape that is obliquely cut with respect to the axial direction, whereby the distance between the plunger-side tip portion 12a and the outer yoke-side tip portion 14a. Even if changes, the suction force can be kept constant.

  The stopper 21 has a cylindrical shape, and has a flange 21a at one end. The stopper 21 is inserted into the through hole 12 b of the plunger 12, and the end portion 12 c on the spool 11 side of the plunger 12 is engaged with the flange portion 21 a formed on the stopper 21. Further, the cylindrical portion of the stopper 21 is press-fitted into the spool 11 until the opening end surface of the press-fitting hole 11b of the spool 11 and the flange portion 21a of the stopper 21 come into contact with each other.

  The spring 19 is disposed in a hole 13 a formed in the inner yoke 14 and is in contact with the flange 21 a side of the stopper 21.

  The spool 11 has a cylindrical shape, and is formed with a communication groove 11a that communicates a port Pi and a port Pc described later. A press-fitting hole 11 b is formed at one end of the spool 11.

  The valve body 10 is formed with a first hole 10a in which the spool 11 slides and a second hole 10b in which the inner diameter is slightly larger than that of the first hole 10a and the spool 11 similarly slides. Ports Pi and Pc, which are oil passages, are formed in the second hole 10b. The valve body 10 has an inner diameter larger than that of the second hole 10b, and a third hole 10c for holding the plunger 12 and the outer yoke 14 is formed. The inner diameter is slightly larger than that of the third hole 10c. A fourth hole 10d that supports the male screw provided in the yoke 14 is formed. The fourth hole 10d is formed with a female screw constituting the adjustment screw 22. Furthermore, the valve body 10 has a slightly larger inner diameter than the fourth hole 10d, and a fifth hole 10e is formed in which the connector portion 23 is disposed. The fifth hole 10e has an inner peripheral surface on the opening end side. A recess 10f is formed in part.

  A radial gap 20 is formed between the outer peripheral surface of the spool 11 into which the stopper 21 of the spool 11 is press-fitted and the through hole 12 b of the plunger 12. The gap portion 20 has a large coaxiality error between the second hole 10b in which the spool 11 formed in the valve body 10 slides and the third hole 10c in which the outer yoke 14 and the plunger 12 are held. However, it is provided in order to make the plunger 12 slide smoothly.

  Adjustment screws 22 are provided on the outer peripheral surface of the outer yoke 14 and the inner peripheral surface of the valve body 10. The adjusting screw 22 can move the inner yoke 13 in the axial direction via the outer yoke 14 by rotating the outer yoke 14. At the time of assembly, the set length of the spring 19 can be adjusted, and the urging force of the spring 19 can be adjusted. Therefore, even if the urging force changes due to an axial dimensional error of each component, it can be adjusted to a predetermined value. After adjusting the set length of the spring 19, the portion of the connector portion 23 facing the recess 10 f of the valve body 10 is heat caulked so that the connector portion 23 and the outer yoke 14 do not rotate.

  In the solenoid valve of this embodiment, the outer yoke 14 and the plunger 12 are held by the inner periphery of the third hole 10 c of the valve body 10. Further, the plunger 12 is disposed between the outer yoke 14 and the spool 11, and all the movable members that move slidably can be collected on the spool 11 side (left side in FIG. 1) from the outer yoke 14. That is, the position of the suction portion is determined only by the inner periphery of the third hole 10c of the valve body 10, the outer periphery of the outer yoke 14, and the outer periphery of the plunger 12, so that the conventionally required shaft and bearing need not be used. Therefore, it is possible to suppress a coaxiality error between the plunger 12 and the outer yoke 14 to reduce a radial error of the suction portion and to exhibit a predetermined suction force.

  Furthermore, the solenoid valve of this embodiment can be attached to the valve body 10 after assembling the spool 11 and the plunger 12 which are movable members and assembling the inner yoke 13, the bobbin 16 and the outer yoke 14 which are fixed members. Therefore, attachment of the solenoid valve to the valve body 10 can be simplified.

  Next, the operation of the solenoid valve will be described.

  FIG. 1 shows a state without energization. The oil supplied from the oil pump (not shown) to the port Pi of the valve body 10 is supplied from the port Pc of the valve body 10 to the controlled object via the communication groove 11a.

  Here, when a current flows from the power source (not shown) to the coil 15 through the terminal 17, a magnetic flux is formed by the coil 15, and an attractive force is generated between the plunger-side tip portion 12a and the outer yoke-side tip portion 14a. . As the plunger 12 moves, the spool 11 also moves simultaneously. Eventually, the plunger 12 comes into contact with the inner yoke 13 via the stopper 21 and stops moving.

  In this state, oil is supplied to the port Pi of the valve body 10, but since the port Pc is closed by the spool 11, oil supply to a control target (not shown) is stopped.

  In addition, although this embodiment was explained in full detail using the spool valve, for example, a ball valve may be sufficient and it is not limited to a valve structure. Moreover, although this embodiment explained in full detail using the hydraulic control valve which controls hydraulic pressure, the pneumatic control valve which controls air pressure may be sufficient.

  Further, in the present embodiment, the valve body 10 in which the outer yoke 14 and the plunger 12 are held and the valve body 10 in which the spool 11 is slid are integrated, but the valve body 10 is integrated. It is not limited. That is, the valve body 10X in which the outer yoke 14 and the plunger 12 are held and the valve body 10Y in which the spool 11 is slid may be configured separately.

It is sectional drawing which shows the solenoid valve of this embodiment. It is A view of the solenoid valve of this embodiment.

Explanation of symbols

10 (10X, 10Y) ... valve body 10a ... first hole 10b ... second hole 10c ... third hole 10d ... fourth hole 10e ... fifth Hole 10f ... Recess 11 ... Spool 11a ... Communication groove 11b ... Press-fitting hole 12 ... Plunger 12a ... Plunger side tip 12b ... Through hole 12c ... End 13 .... Inner yoke 13a ... Hole 13b ... First flange 13c ... Second flange 14 ... Outer yoke 14a ... Outer yoke side tip 15 ... Coil 16 ··· Bobbin 17 ··· Terminal 18 · · · Connector holder 19 · · · Spring 20 · · · Gap 21 · · · Stopper 21a · · · flange 22 · · · Adjustment screw 23 · · · Connector portion Pi · · · ..Input port Pc ... Output (control target) Over door

Claims (6)

A valve body in which a fluid passage is formed;
An inner yoke made of a magnetic material;
A cylindrical bobbin disposed around the inner yoke and wound with a coil;
A cylindrical outer yoke made of a magnetic material disposed on the outer peripheral side of the bobbin and fixed to the inner yoke;
A cylindrical plunger that is disposed on the outer peripheral side of the bobbin and is made of a magnetic material that is movable in one axial direction of the bobbin by energizing the coil;
A valve member disposed in the valve body so as to be able to open and close the fluid passage, and movable with the plunger;
A solenoid valve, comprising: a biasing member that biases the plunger and the valve member to the other axial direction of the bobbin. In claim 1,
The solenoid valve according to claim 1, wherein the outer yoke and the plunger are held by an inner periphery of the valve body. In claim 1 or claim 2,
The solenoid valve, wherein the plunger is disposed between the outer yoke and the valve member. In claim 3,
A stopper provided on one end of the valve member and having a flange;
The plunger has a cylindrical shape with a through hole formed at the end on the valve member side,
The valve member is inserted into the through hole of the plunger so that the flange and the end of the plunger on the valve member side are engaged, and a gap is formed between the plunger and the valve member. Solenoid valve characterized by being. In Claims 2 to 4,
A solenoid valve characterized in that an adjustment mechanism for adjusting an axial position of the outer yoke is formed on an outer peripheral surface of the outer yoke and an inner peripheral surface of the valve body. In claim 5,
The adjusting mechanism includes a male valve formed on an outer peripheral surface of the outer yoke and a female screw formed on an inner peripheral surface of the valve body.

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