JPH11351429A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend the lives of a seal member and a solenoid valve by preventing the deterioration and damage to the seal member. SOLUTION: A valve element 4 for closing from an outlet side a port 5 to which fluid is introduced is arranged in this solenoid valve, and an elastic seal member 27 having a cylindrical part 31 inserted in a port outlet part 22 is arranged on this valve element 4. When the port 5 is closed, the valve element 4 is pressed against a valve seat 23 formed on a port outlet peripheral side and the cylindrical part 31 is pressed against the inner wall 34 of the port outlet part 22 by fluid pressure in a port.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve used for controlling fluid pressure such as pneumatic pressure and hydraulic pressure.

[0002]

2. Description of the Related Art As a general structure of a solenoid valve, there is one shown in FIG. That is, this is the ON / O of coil 1.
A plunger 2 that moves up and down according to the FF is provided, and a valve body 4 is attached to the plunger 2 via a push rod 3. When the valve body 4 is moved up and down in accordance with the elevating operation of the plunger 2, the fluid introduction port 5 is opened and closed from the outlet side in response to this. The illustrated solenoid valve is of a three-way type. When the coil 1 is turned on and the valve body 4 is raised, the fluid (here, air) at the introduction port 5 is introduced into the valve chamber 6 as indicated by arrow A, and supplied. It is supplied to an external actuator or the like through the port 7. When the coil 1 is turned off and the valve body 4 is lowered, the introduction port 5 is closed and the introduction of the fluid is shut off, and the fluid supplied through the supply port 7 flows backward, as indicated by arrow B. The gas is discharged from the discharge hole 19 to the outside through the valve chamber 6, the outlet port 8 (gap around the push rod 3), the discharge passage 9, and the discharge port 10.

[0003] When the valve body 4 is raised, the outlet port 8 is closed, whereby discharge of the fluid is prohibited, and only supply is possible.

The push rod 3 is only fitted to the plunger 2 and the valve body 4 so as to be freely inserted and withdrawn, and the valve body 4 can only act on the valve in the closing or pushing direction. So coil 1
Is turned on, the valve body 4 follows the rise of the plunger 2.
In order to raise the push rod 3, the valve body 4 is fitted with a valve opening spring 11 for urging the valve body 4 in the valve opening direction. On the other hand, a valve closing spring 12 for urging the plunger 2 in the valve closing direction is fitted in the plunger 2. Thus, when the coil 1 is turned off, the plunger 2 is lowered, and the valve element 4 can be lowered against the urging force of the valve opening spring 11.

[0005]

As shown in detail in FIG. 5, a protruding valve seat 13 is provided on the outer peripheral side of the outlet of the introduction port 5, and this valve seat 13 is attached to the valve body 4. By pressing the provided rubber seal 14 for valve closing, the outlet of the introduction port 5 is closed, and at the same time, fluid leakage is prevented. Similarly, when the introduction port 5 is opened, the derivation port 8
The rubber seal 16 for valve opening is pressed against the valve seat 15 (see FIG. 4) on the outer peripheral side of the inlet of the valve to prevent discharge of fluid.

However, in such a configuration in which the rubber seals 14 and 16 are directly and locally pressed against the valve seats 13 and 15, the rubber seals 14 and 16 themselves become brittle due to deterioration with time, so that the rubber seals 14 and 16 are combined. In FIG. 16, there is a problem that a dent 17 and a crack 18 as shown in FIG. 6 are likely to be generated, whereby the function of the seal is not fulfilled, and as a result, the life of the solenoid valve is shortened. In particular, the rubber seal 14 for valve closing is strongly pressed against the valve seat 13 which is a metal surface from the opposite direction against the introduction of the fluid, so that the rubber seal 14 is significantly deteriorated and damaged by repeated strong compression.

[0007]

The solenoid valve according to the present invention comprises:
A valve body for closing the port from which the fluid is introduced is provided from the outlet side, and the valve body is provided with an elastic seal member having a cylindrical portion inserted into the port outlet, and when the port is closed,
The valve body is pressed against a valve seat formed on the outer peripheral side of the port outlet, and the cylindrical portion is pressed against the inner wall of the port outlet portion by fluid pressure in the port.

Here, it is preferable that the diameter of the port outlet is enlarged, the cylindrical portion is coaxially inserted into the enlarged diameter portion, and the inner diameter of the cylindrical portion is larger than the port diameter.

The inner wall of the port outlet portion is tapered so that the diameter gradually increases toward the outlet side, and the outer peripheral surface of the distal end of the cylindrical portion has the tapered shape of the inner wall of the port outlet portion. It is preferable that the tapered shape is imitated.

It is preferable that a portion of the valve body pressed against the valve seat is formed of a metal sealing material such as copper.

On the other hand, in the solenoid valve according to the present invention, an inlet portion of a port from which a fluid is discharged is defined by a cylindrical member, and a valve body for closing the port from the inlet side has an outer periphery of the cylindrical member. An elastic seal member having a tubular portion fitted to the side is provided, and when the port is closed, the valve body is pressed against a valve seat formed on the outer peripheral side of the tubular member, and the tubular portion is removed. The fluid pressure on the upstream side of the port presses against the outer wall of the tubular member.

Here, the outer wall of the cylindrical member is tapered so that the diameter gradually decreases toward the inlet side, and the inner peripheral surface of the distal end of the cylindrical member has the tapered shape of the outer wall of the cylindrical member. It is preferred that the tapered shape follows.

Further, it is preferable that a portion of the valve body pressed against the valve seat is formed of a metal sealing material such as copper.

[0014]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, in this embodiment, only the structure of the solenoid valve in the vicinity of the valve body is different. As described above, the introduction port 5, the valve chamber 6, the supply port 7, and the outlet port 8 are defined in the valve body 21, and the valve body 4 accommodates the valve body 4 in a vertically movable manner. , A push rod 3 is fitted, and a valve opening spring 11 is fitted on the outer peripheral side of the valve body 4. The valve body 21, the valve body 4, the push rod 3, and the valve-opening spring 11 are formed of a normal metal material such as iron. The introduction port 5, valve chamber 6, valve body 4, outlet port 8, push rod 3, and valve opening spring 11 are coaxially arranged. The introduction port 5 opens at the bottom of the valve chamber 6, the outlet port 8 opens at the top of the valve chamber 6, and the supply port 7 opens at the side of the valve chamber 6.

The inlet port 5 basically has an inner diameter D ₁ , but the outlet portion 22 has an enlarged diameter, and is formed in a tapered shape in which the diameter gradually increases toward the outlet side. An annularly projecting valve seat 23 is formed on the outer peripheral side of the outlet. Here, when the introduction port 5 is closed, the valve body 4 itself is seated as shown in the figure. Note that these seating surfaces are flat. The bottom surface 24 on the outer peripheral side of the valve seat 23 is depressed in a rounded cross section so that the valve opening spring 11 can be positioned.

The valve body 4 is formed in a solid cylindrical shape, and has an outer peripheral projection 25 on its top for receiving the urging force of the valve opening spring 11, and a valve opening spring on a lower portion of the outer peripheral projection 25. 11 are fitted. At the center position, there is a bottomed fitting hole 26 that opens upward, and the push rod 3
Is fitted so as to be freely inserted and removed. The push rod 3 passes through the axial portion of the outlet port 8 with a gap,
The upper end is fitted to the plunger 2 described above.

At the lower end of the valve body 4, a valve closing seal member 27 is provided in place of the conventional valve closing rubber seal 14. The valve-closing seal member 27 is an integrally molded product made of an elastic material such as rubber, and has a disk-like portion 28 forming the upper end or the base end thereof.
And a cylindrical portion 29 protruding downward from the disk-shaped portion 28 and coaxially inserted into the outlet portion 22 of the introduction port 5. A fitting recess 30 is formed on the bottom surface of the valve body 4, and the disc-shaped portion 28 is fitted and attached to the fitting recess 30, whereby the valve closing seal member 27 is attached to the valve body 4. You. D ₂ (inner diameter of the fitting recess 30) the outer diameter of the disc-shaped portion 28 is smaller in diameter than the inner diameter D ₃ of the outlet end of inlet port 5, which permits the valve body 4 itself seated on the valve seat 23 .

The cylindrical portion 29 has an outer peripheral surface 31 formed in a gently rounded shape in which the outer peripheral surface 31 falls down from the disk-shaped portion 28, while the inner peripheral surface 32 has a linear cross-sectional shape along the axial direction of the introduction port 5. Is done. The inner diameter D ₄ of the cylindrical portion 29 is equal to or larger than the inner diameter D ₁ of the introduction port 5 here. Thereby, the internal space of the cylindrical portion 29 is completely communicated with the introduction port 5. The outer peripheral surface 33 at the distal end of the cylindrical portion 29 has a tapered shape following the tapered shape of the inner wall 34 of the outlet portion 22 so that the entire surface can be in close contact with the inner wall 34.

Meanwhile, the outlet port 8, has a constant inner diameter D ₅ over the entire length, the inlet portion is partitioned and formed in the tubular member 35. The tubular member 35 is formed integrally with the valve body 21 and protrudes downward along the axial direction of the outlet port 8. The outer wall 36 of the cylindrical member 35 is formed in a tapered shape in which the diameter gradually decreases toward the entrance side. An annular projecting valve seat 37 is formed on the outer peripheral side of the cylindrical member 35, and the valve body 4 itself is seated when the outlet port 8 is closed as described above. These seating surfaces are plane. The valve seat 37 is located below the lower end of the tubular member 35. The top surface 38 located on the outer peripheral side of the valve seat 37 is recessed in a cross-sectionally round shape symmetrically with the bottom surface 24.

A valve opening seal member 39 is provided at the upper end of the valve body 4 in place of the conventional valve opening rubber seal 16 as described above. The valve-opening sealing member 39 is also an integrally molded product made of an elastic material such as rubber, and has a disk-shaped portion 40 forming a lower end or a base end thereof, and protrudes upward from the disk-shaped portion 40 to form an outer peripheral side of the cylindrical member 35. And a cylindrical portion 41 coaxially fitted with the cylindrical portion. A fitting recess 42 is formed on the top surface of the valve body 4, and the disc-shaped portion 40 is fitted and attached to the fitting recess 42, whereby the valve-opening seal member 39 is attached to the valve body 4. You. Outer diameter of disk-shaped part 40 (inner diameter of fitting concave part 42) D ₆
It is smaller in diameter than the inner diameter D ₇ of the valve seat 37, thereby the valve seat 3
The seating of the valve element 4 itself on 7 becomes possible. The cylindrical portion 41
A radial gap 50 is created between the valve seat 37 and the valve seat 37.

The cylindrical portion 41 has an outer peripheral surface 43 and an inner peripheral surface 4.
4 are both linear in cross section along the axial direction of the outlet port 8, but the inner peripheral surface 45 at the distal end or upper end is a cylindrical member 35.
The outer wall 36 has a tapered shape following the tapered shape of the outer wall 36 so that the entire surface can be in close contact with the outer wall 36.

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

As described above, a fluid (here, air) having a predetermined pressure is constantly supplied to the introduction port 5 from the outside. When the coil 1 shown in FIG. 4 is turned off, the valve body 4 descends as shown in FIG. 1, and the introduction port 5 is closed,
The introduction of the fluid into the valve chamber 6 is shut off.

That is, at this time, the valve body 4 itself is strongly pressed against the valve seat 23. That is, the pressing reaction force is received by the valve body 4 itself. Thereby, the valve closing seal member 2
7 does not have to be pressed against the valve seat 23, and the valve-closing seal member 2
7 can be prevented beforehand. The life of the valve-closing seal member 27 and thus the life of the solenoid valve can be extended.

On the other hand, the cylindrical portion 29 of the valve-closing seal member 27 is inserted into the outlet portion 22 of the introduction port 5. The inner peripheral surface 32 of the cylindrical portion 29 As a result, the cylindrical portion 29 receives a force in the radially expanding direction,
Sometimes it is slightly deformed. As a result, the tip outer peripheral surface 33 is particularly strongly pressed against the inner wall 34 of the outlet 22,
Fluid leakage is forbidden and a perfect seal can be achieved. In addition, when the fluid pressure increases, the pressing force becomes stronger, so that a complete self-sealing can be achieved.
Further, since the tapered surfaces are brought into close contact with each other, the close contact and sealing can be performed reliably and strongly.

Since a downward pressing force is not required as in the prior art, the urging force of the valve closing spring 12 shown in FIG. 4 can be reduced, thereby improving the responsiveness when the coil 1 is turned on. The coil 1 can also be a small power-saving coil.

On the other hand, when the coil 1 shown in FIG.
The valve body 4 rises, the introduction port 5 is opened, and the fluid is introduced into the valve chamber 6 and flows to the supply port 7. At the same time, the outlet port 8 is closed, and leakage of the fluid to the outlet port 8 is prohibited.

That is, also at this time, the valve body 4 itself is connected to the valve seat 37.
Pressed to. Since the valve body 4 can receive the pressing reaction force, the valve opening seal member 39 is deteriorated,
It can protect from damage.

At this time, the cylindrical portion 41 of the valve opening seal member 39 is fitted to the cylindrical member 35.
When the outer peripheral surface 43 receives the fluid pressure in the valve chamber 6, particularly in the gap 50, the cylindrical portion 41 receives a force in the diameter reducing direction,
Sometimes it is slightly deformed. As a result, the inner peripheral surface 45 of the distal end portion is particularly strongly pressed against the outer wall 36 of the tubular member 35, thereby preventing leakage of the fluid and at the same time achieving the same self-sealing as described above.

Here, in the above configuration, since the valve element 4 is pressed against the valve seats 23 and 37, sealing can be performed even at this portion, and even if the sealing members 27 and 39 are cut off, a large amount of fluid is used. Can be prevented from leaking. However, if it is desired to more reliably seal the portion, as shown in FIG. 2, the portion of the valve body 4 that is pressed against the valve seats 23 and 37 may be formed of a metal sealing material such as copper.

That is, in this case, the seating portions 46 and 47 on the outer peripheral side of the valve closing seal member 27 and the valve opening seal member 39 in the valve body 4 are formed of the above metal sealing material. A lip portion 48 is formed on each of the seating portions 46 and 47 so that connection with the valve body 4 main body can be firmly performed. In addition, these seating parts 46 and 47 are formed in an annular shape as a whole.
As the metal sealing material, a metal softer than the metal material forming the valve seats 23 and 37 is preferably selected. Thus, the adhesion to the valve seats 23 and 37 is enhanced, and the seating portions 46 and 47 are provided.
Sealing can also be performed at the contact portions between the valve seats 23 and 37.

Although the above is an example of a three-way solenoid valve, the number of ports of the solenoid valve is not limited. For example, a configuration relating to a two-way solenoid valve as shown in FIG. 3 can be adopted.
In this case, the valve body 4 is shared with the plunger 2 and has a valve closing seal member 27 at the lower end. There are only two ports, the introduction port 5 and the supply port 7, and the introduction port 5 is closed. Since other configurations are substantially the same, the same portions are denoted by the same reference numerals and description thereof will be omitted.

The present invention can adopt various other embodiments. For example, the fluid is not limited to air, but may be oil or the like.

[0035]

The present invention exhibits the following excellent effects.

(1) The deterioration and damage of the seal member can be prevented, and the life of the seal member and the solenoid valve can be extended.

(2) Self-sealing can be achieved, and reliable sealing can be achieved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a solenoid valve according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a main part of a solenoid valve according to another embodiment.

FIG. 3 is a longitudinal sectional view showing a solenoid valve according to another embodiment.

FIG. 4 is a longitudinal sectional view showing a conventional solenoid valve.

FIG. 5 is a longitudinal sectional view showing a configuration around a valve body of a conventional solenoid valve.

FIG. 6 is a cross-sectional view of the rubber seal shown in FIG.
FIG.

[Explanation of symbols]

4 valve body 5 introduction port (port) 8 outlet port (port) 22 outlet part (port outlet part) 23 valve seat 27 valve closing seal member (elastic seal member) 31 cylindrical part 33 outer peripheral surface 34 inner wall 35 cylindrical member 36 outer wall 37 valve seat 39 opening sealing member (elastic seal member) 41 cylindrical portion 45 inner peripheral surface 46 and 47 seat (part pressed against the valve seat) D ₁ inlet port inner diameter (port diameter) D ₄ cylinder Inner diameter

Claims (7)

[Claims] 1. A valve body for closing a port into which a fluid is introduced from an outlet side, an elastic seal member having a cylindrical portion inserted into a port outlet portion is provided on the valve body, At the time of closing, the valve body is pressed against a valve seat formed on the outer peripheral side of the port outlet, and the cylindrical portion is pressed against the inner wall of the port outlet portion by fluid pressure in the port. solenoid valve. 2. The electromagnetic device according to claim 1, wherein the diameter of the port outlet is enlarged, the cylindrical portion is coaxially inserted into the enlarged diameter portion, and the inner diameter of the cylindrical portion is equal to or larger than the port diameter. valve. 3. An inner wall of the port outlet portion is tapered so as to gradually increase in diameter toward the outlet side, and an outer peripheral surface of a tip portion of the cylindrical portion has a tapered shape of an inner wall of the port outlet portion. 3. The solenoid valve according to claim 1, wherein the solenoid valve has a tapered shape. 4. The solenoid valve according to claim 1, wherein a portion of the valve body pressed against the valve seat is formed of a metal sealing material such as copper. 5. A tubular member which is formed by partitioning an inlet portion of a port from which a fluid is led out with a cylindrical member and which is fitted to an outer peripheral side of the cylindrical member to a valve body for closing the port from the inlet side. An elastic seal member having a portion is provided, and when the port is closed, the valve body is pressed against a valve seat formed on the outer peripheral side of the cylindrical member, and the cylindrical portion is pressed by a fluid pressure on the port upstream side. An electromagnetic valve, wherein the electromagnetic valve is pressed against an outer wall of the tubular member. 6. The outer wall of the cylindrical member is tapered so that the diameter gradually decreases toward the inlet side, and the inner peripheral surface of the distal end of the cylindrical member has the tapered shape of the outer wall of the cylindrical member. 6. The solenoid valve according to claim 5, wherein the solenoid valve is shaped like a taper. 7. The solenoid valve according to claim 5, wherein a portion of the valve body that is pressed against the valve seat is formed of a metal sealing material such as copper.