JPH0719681U - Solenoid valve piston - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a solenoid valve piston that can completely prevent leakage of a working fluid without cutting a parting line, and that does not allow a sealing material to drop from a piston body. [Structure] Piston body 26 and V ring (seal material) 2
7, the piston body 26 is a cylindrical body 2
6a, a flange portion 26b formed on one end side of the main body portion 26a, and an annular fitting groove 26c between the main body portion 26a and the flange portion 26b. The convex portion 27a formed in a part is fitted into the fitting groove 26c, and the other inner peripheral surface is closely attached to the main body portion 26a to be mounted on the piston main body 26. Then, the parting line 28 is formed only on the flange portion 26b and the fitting groove 26c of the piston body 26, and the outer peripheral surface of the body portion 26a is made flat. With such a configuration, the inner peripheral surface of the V ring 27 can be attached to the main body portion 26 without cutting the parting line 28.
It becomes possible to make close contact with a.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a solenoid valve piston used in a solenoid valve for displacing a spool shaft to switch a flow path of a working fluid and controlling the operation of a predetermined fluid pressure working device.

[0002]

[Prior art]

 The solenoid valve that operates by electromagnetic operation displaces the spool shaft by the plunger attraction of the column magnetized by energizing the solenoid coil and the sliding action of the solenoid valve piston provided at the end of the spool shaft. The flow path of the working fluid is switched by. Therefore, the seal material mounted on the solenoid valve piston must have sufficient sealability to prevent leakage when the working fluid flows in and pressurizes the fluid chamber. It is said that In particular, when an inert gas such as carbon dioxide is used as the working fluid, it is required to secure the sealing property from the viewpoint of cost.

However, as shown in FIG. 4 and FIG. 5 which is a cross-sectional view taken along the line VV, in the conventional solenoid valve piston 44, the seal member 47 is detached from one side of the cylindrical body portion 46 a. Since the stopper portion 46d for preventing this has a shape in which the flange portion 46b is formed on the other side, the die for molding this must have a structure that divides the piston body 46 into two in the axial direction. I don't get it. Then, the mating parts (hereinafter referred to as “parting lines”) 48 of the mold at the time of molding are formed at both ends in the axial direction of the piston main body 46, and the sealing material 47 of the mounted seal member 47 is A part of the inner peripheral surface may float up from the main body 46a and the working fluid may leak, impairing the sealing performance.

In such a case, it is conceivable to apply grease to the floating portion, but since the effect is diminished by repeated sliding of the solenoid valve piston 44, it may be a permanent measure. Absent.

Therefore, conventionally, a part that comes into contact with the sealing material 47, that is, the parting line 48 formed in the main body portion 46a is cut with a tool, thereby bringing the main body portion 46a and the sealing material 47 into close contact with each other. To prevent the working fluid from leaking.

[0006]

[Problems to be solved by the device]

 However, it is not efficient to cut the parting line 48 formed on the main body portion 46a after the piston main body 46 is formed, and the part between the piston main body 46 and the seal material 47 is not cut through such a cutting process. It is desirable to prevent leakage of the working fluid in the.

Therefore, an object of the present invention is to provide a technique relating to a solenoid valve piston capable of completely preventing a working fluid from leaking without cutting a parting line.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0009]

[Means for Solving the Problems]

 The typical ones of the inventions disclosed in the present application will be outlined as follows.

That is, the solenoid valve piston according to the present invention comprises a piston body and a sealing material. The piston body is formed of a cylindrical body portion, a flange portion formed on one end side of the body portion, and an annular fitting groove formed between the body portion and the flange portion. In addition, the sealing material is mounted on the piston body while the convex part formed on a part of the inner peripheral surface in the circumferential direction fits into the fitting groove, and the other inner peripheral surface is in close contact with the body part. It is a thing. Further, the parting line is formed only in the flange portion and the fitting groove of the piston main body, and is flat on the outer peripheral surface of the main body portion without existing.

[0011]

[Action]

 According to the solenoid valve piston configured as described above, the inner peripheral surface of the seal material attached to the piston body is brought into close contact with the body portion without cutting the parting line. Therefore, the sealing material does not fall off from the piston body due to the fitting of the convex portion of the sealing material and the fitting groove, and it is possible to completely prevent the leakage of the working fluid between the piston body and the sealing material. it can.

[0012]

【Example】

 Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a sectional view showing an electromagnetic valve using an electromagnetic valve piston according to an embodiment of the present invention, FIG. 2 is a sectional view showing the electromagnetic valve piston, and FIG. FIG. 3 is a sectional view taken along line III-II I.

The valve block portion 2 of the solenoid valve 1 is supplied with a working fluid from a fluid pressure supply device (not shown), and an air supply opening 3 is provided for controlling the operation of a predetermined fluid pressure operation device. First and second output openings 4a and 4b through which the fluid flows out and first and second exhaust openings 5a and 5b through which the working fluid is discharged are formed facing the shaft hole 6, respectively. ing.

A spool shaft 7 is housed in the axial direction of the shaft hole 6, and spool grooves 7 a are formed in the spool shaft 7 at predetermined intervals and O-rings 8 a to 8 d are attached to the spool shaft 7. And the O-rings 8a to 8d form a spool portion.

In the state where the spool shaft 7 is in the first position as shown in FIG. 1, the air supply opening 3 is closed by the O-rings 8 a and 8 c of the spool shaft 7 to form the first output opening 4 a. The second output opening 4b and the second exhaust opening 5b communicate with each other. Further, when the spool shaft 7 is displaced rightward in FIG. 1 to the second position, the air supply opening 3 is closed by the O-rings 8b and 8d of the spool shaft 7 and opened for the second output. The first output opening 4a and the first exhaust opening 5a communicate with each other through the mouth 4b.

Next, the structure of the solenoid portion 9 for operating the spool shaft 7 in the first position shown in FIG. 1 and the second position displaced to the right will be described.

The bobbin 10 of the solenoid portion 9 has a solenoid 11 formed by winding a conductive wire around the bobbin 10, and a yoke 12 is provided on the outer side thereof. A column 13 is fitted in the rear part of the bobbin 10, and a plunger 14 is mounted in the front part of the bobbin 10 slidably in the axial direction. The members forming these solenoid parts 9 are sealed by a housing 15 made of, for example, resin.

A valve seat portion 18 that closes an air supply hole 17 that communicates with the air supply opening 3 by a communication channel 16 is fitted to the tip end portion of the plunger 14, and the plunger 14 also has a valve seat portion 18. The compression coil spring 19 urges the elastic force in the direction of retracting it. Therefore, when the solenoid 11 is not energized, the air supply hole 17 is closed by the valve seat portion 18 by the elastic force of the compression coil spring 19.

At the front portion of the plunger 14, that is, at one end side of the spool shaft 7, a valve body 23 that opens and closes a discharge passage 22 by an interlocking pin 20 and a compression coil spring 21 that interlock with the movement of the plunger 14 in the axial direction. Is provided, the first solenoid valve piston 24 is provided, and the first fluid chamber 25 is formed. When the solenoid 11 is energized, the plunger 14 moves backward to release the air supply hole 17, and the working fluid from the air supply opening 3 flows into the first fluid chamber 25, whereby the first fluid chamber 25 Is pressurized, and the first solenoid valve piston 24 slides to come into contact with one end surface of the spool shaft 7 and displace it.

As shown in FIGS. 2 and 3, the first solenoid valve piston 24 includes a piston body 26 made of resin and a V ring (seal material) 27 having a substantially V-shaped cross section. It consists of and. The piston body 26 includes a cylindrical body portion 26a, a flange portion 26b formed at one end of the body portion 26a, and an annular fitting groove formed between the body portion 26a and the flange portion 26b. On the other hand, a convex portion 27a that fits into the fitting groove 26c is formed at the base end portion of the inner peripheral surface of the V ring 27.

By providing the flange portion 26b and the fitting groove 26c on one side of the main body portion 26a of the piston main body 26, a mold (not shown) for molding the piston main body 26 has one side of the main body portion 26a. On the side of 26a, the other side is divided into a flange portion 26b and a fitting groove 26c side, and further divided into a flange portion 26b side and a fitting groove 26c side. Therefore, the parting line 28, which is a part of the mold to be fitted at the time of molding, is formed only in the flange portion 26b and the fitting groove 26c, and the outer peripheral surface of the main body portion 26a becomes flat, and the inner peripheral surface of the mounted V ring 27 is formed. The surface is in close contact with the main body portion 26a.

A second solenoid valve piston 29 for displacing the spool shaft 7 in the opposite direction is provided on the other end side of the spool shaft 7, and a second fluid for sliding the second solenoid valve piston 29 is provided. A chamber 30 is formed in communication with the air supply opening 3 by a communication flow path 31. The shape of the second solenoid valve piston 29 is the same as the shape of the first solenoid valve piston 24.

Further, the pressure receiving area of the second solenoid valve piston 29 is set to be smaller than that of the first solenoid valve piston 24, so that the working fluid from the air supply opening 3 is applied to both solenoids. When acting on the valve pistons 24 and 29, the first solenoid valve piston 24 is adapted to displace the spool shaft 7 by overcoming the second solenoid valve piston 29.

When the solenoid 11 of the solenoid portion 9 is not energized, the working fluid is supplied only to the second fluid chamber 30. Therefore, the spool shaft 7 pressurizes the second fluid chamber 30. It is displaced by the second solenoid valve piston 29 that comes into sliding contact with the second solenoid valve and comes to the first position shown in FIG. At this time, the air supply opening 3 and the first output opening 4a communicate with each other, and the second output opening 4b and the second exhaust opening 5b communicate with each other.

On the other hand, when the solenoid 11 is energized, the plunger 14 moves backward against the elastic force of the compression coil spring 19. As a result, the air supply hole 17 is opened and the discharge path 22 is closed by the valve body 23, so that the working fluid in the air supply opening 3 is also supplied to the first fluid chamber 25 through the communication flow path 16. As a result, the spool shaft 7 is displaced by the first solenoid valve piston 24 to the second position. At this time, the air supply opening 3 communicates with the second output opening 4b, and the first output opening 4a communicates with the first exhaust opening 5a.

As described above, in the solenoid valve 1, the spool shaft 7 is displaced by the sliding movement of the two solenoid valve pistons 24 and 29. Further, according to the first and second electromagnetic valve pistons 24 and 29 of the present embodiment, since the parting line 28 is not formed in the body portion 26a, the V ring 27 attached to the piston body 26 is provided. The inner peripheral surface thereof is brought into close contact with the main body portion 26a. Therefore, the protrusion 27a of the V-ring 27 and the fitting groove 26c are fitted together to prevent the V-ring 27 from falling off, while completely preventing the leakage of the working fluid between the piston body 26 and the V-ring 27. Be touched.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, in the present embodiment, the solenoid valve 1 in which the spool shaft 7 is displaced both rightward and leftward by the solenoid valve pistons 24 and 29 has been described. It is also possible to use, for example, a compression coil spring.

Further, the sealing material mounted on the solenoid valve pistons 24, 29 is not limited to the V ring 27, and various sealing materials such as mounting a sealing material having a substantially X-shaped cross section can be used. Materials can be used. Furthermore, the convex portion 27a does not necessarily have to be formed at the base end portion, and can be formed at any position as long as it is a part of the inner peripheral surface in the circumferential direction.

The piston body 26 is not necessarily made of resin, and metal can be used.

[0032]

[Effect of device]

 The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) That is, the solenoid valve piston according to the present invention is flat without a parting line on the outer peripheral surface of the main body of the piston body, and the inner peripheral surface of the sealing material is in the circumferential direction. It is possible to fit the convex portion formed on a part of the above into the fitting groove, and to fit the other inner peripheral surface to the main body portion in close contact with the piston main body.

(2) Therefore, it is possible to completely prevent the leakage of the working fluid between the piston body and the seal material without cutting the parting line formed on the piston body with a tool.

[Brief description of drawings]

FIG. 1 is a sectional view showing a solenoid valve using a solenoid valve piston according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the solenoid valve piston.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a cross-sectional view showing a conventional solenoid valve piston.

5 is a cross-sectional view taken along the line VV of FIG.

[Explanation of symbols]

 1 Solenoid Valve 2 Valve Block 3 Air Supply Opening 4a First Output Opening 4b Second Output Opening 5a First Exhaust Opening 5b Second Exhaust Opening 6 Shaft Bore 7 Spool Shaft 7a Spool Groove 8a O-ring 8b O-ring 8c O-ring 8c O-ring 8d O-ring 9 Solenoid part 10 Bobbin 11 Solenoid 12 Yoke 13 Column 14 Plunger 15 Housing 16 Communication passage 17 Air supply hole 18 Valve seat 19 Compression coil spring 20 Interlocking pin 21 Compression coil spring 22 Discharge path 23 Valve body 24 First piston for solenoid valve 25 First fluid chamber 26 Piston body 26a Main body portion 26b Flange portion 26c Fitting groove 27 V ring (sealing material) 27a Convex portion 28 Parting line 29 Second solenoid valve Piston 30 Second fluid chamber 31 Communication channel 44 Solenoid valve piston 46 Pist Body 46a Body 46b Flange 46d Stopper 47 Sealing material 48 Parting line

Claims (3)

[Scope of utility model registration request] 1. A solenoid valve used for displacing a spool shaft to switch a flow path of a working fluid to control the operation of a predetermined fluid pressure operating device, and pressurizing a fluid chamber at at least one end of the spool shaft. A solenoid valve piston for axially displacing the spool shaft by sliding by means of: a cylindrical main body, a flange formed at one end of the main body, the main body and the flange. The piston body consisting of an annular fitting groove formed between the inner peripheral surface and the convex portion formed in a part of the inner peripheral surface in the circumferential direction fits with the fitting groove, and the other inner peripheral surface is A seal member that is attached to the piston body in close contact with the main body portion, and a parting line that is a mold matching portion at the time of molding is formed only in the flange portion and the fitting groove,
A solenoid valve piston, wherein an outer peripheral surface of the main body is flat. 2. The sealing material has a substantially V-shaped cross section,
The solenoid valve piston according to claim 1, wherein the convex portion is formed at a base end portion thereof. 3. The piston for a solenoid valve according to claim 1, wherein the piston body is made of resin.