JPH0322612Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a technology that is effective when applied to change the direction of fluid such as air and control the flow rate. It relates to techniques that are particularly effective when used.

[Conventional technology]

This type of switching valve includes, for example, a shaft hole formed in the valve portion, a plurality of valve seats formed coaxially with the shaft hole midway in the axial direction of the shaft hole, and a plurality of valve seats formed in the shaft hole in the axial direction. An integral movable shaft is mounted so as to be movable along the axial direction, and a plurality of outer circumferential parts of the movable shaft are brought into contact with a valve seat interposed between the outer circumferential parts, and the valve hole is opened. There is something that makes me uncomfortable. In some cases, the outer circumferential portion of the movable shaft is formed by a sealing member, and in others, the outer circumferential portion of the movable shaft is formed by the movable shaft itself, and the valve seat is formed by a sealing member.

Furthermore, the electromagnetic force of a solenoid, the biasing force of a spring, and the like are normally used as a driving source for the movable shaft.

[Problem that the invention attempts to solve]

However, the switching valve having the above-mentioned structure has a structure in which the plurality of outer circumferential parts of the movable shaft abut against respective valve seats interposed between the outer circumferential parts, thereby closing the valve hole. The outer peripheral portion of the movable shaft is formed to have a larger diameter than the inner diameter of the valve hole. Therefore, even if an attempt is made to insert the movable shaft into the shaft hole when manufacturing the valve, the outer peripheral portion of the movable shaft will come into contact with the valve seat, making it impossible to pass through the valve hole.

For this reason, for example, in a switching valve in which a predetermined outer circumferential portion is formed by a sealing member, after inserting the movable shaft with one sealing member attached into the shaft hole, while maintaining this inserted state, the other The sealing member must be attached to the movable shaft within the shaft hole, which requires a complicated assembly process.

In addition, in order for the movable shaft to be inserted into the shaft hole, the movable shaft itself on the insertion direction side must pass through the valve hole, so the outer diameter of the movable shaft itself must be smaller than the inner diameter of the valve hole. is formed.

Therefore, the pressure receiving area at the portion where the outer circumferential surface of the movable shaft itself is sealed is smaller than the pressure receiving area at the outer circumferential portion of the movable shaft that contacts the valve seat, and the pressure receiving areas of the two portions are different.

This difference generates an axial force on the movable shaft due to the fluid pressure introduced into the shaft hole between the two. Therefore, it is necessary to increase the driving force for the movable shaft, such as the biasing force of a spring, by the amount of the axial force, which in turn requires increasing the size of the solenoid section.

On the other hand, in the aforementioned switching valve, the stroke of the movable shaft differs due to errors in the precision of parts such as the movable shaft, especially errors in the outer circumference of the movable shaft or the dimensions and hardness of the sealing member of the valve seat. There is a problem that the flow rate flowing through the pipe is not constant.

The present invention was developed in view of the above-mentioned problems, and its purpose is to create a structure that facilitates assembly, reduces the driving force of the movable shaft, and also allows for flow rate adjustment. The objective is to provide a switching valve that can

[Means for solving problems]

The present invention includes a valve driving part, a valve part connected to the valve driving part, a shaft hole formed in the valve part, a valve seat formed in the shaft hole, and a valve seat connected to the shaft hole. A switching valve comprising a movable valve body disposed so as to be freely movable along the axial direction, and the movable valve body is brought into contact with and separated from a valve seat to open and close the valve hole thereof, the movable valve body comprising: A structure in which a pair of split members that can be separated from each other in the axial direction are screwed together and coaxially connected to each other, and the length in the axial direction can be adjusted by threading the split members together. This is what is being done.

[Effect]

According to the above-described means, since the movable valve body is formed of a divided member, when manufacturing the valve,
After inserting one divided member having an outer peripheral portion such as a seal member into the shaft hole from one opening of the shaft hole, insert the other divided member having an outer peripheral portion such as a seal member into the other opening of the shaft hole. Since it is possible to assemble the two divided members by inserting them into the shaft hole and connecting them by screwing them together, there is no need to attach the outer peripheral parts such as the sealing member in the shaft hole, and therefore the valve can be easily assembled. It is possible to aim for

In particular, since the divided members are connected to each other by screwing, the valve can be easily assembled by this screwing connection.

In addition, since the movable valve body is formed by connecting the divided members by screwing them together, the number of parts can be reduced and the structure can be simplified, and from this point of view as well, the assembly of the valve can be facilitated. I can do it.

In addition, since such an assembly can be performed, the outer diameter of the movable valve body itself is formed to be larger than the inner diameter of the valve hole, and the outer circumferential surface of the movable valve body itself is sealed and the valve seat. The pressure-receiving area can be made the same size as the outer circumferential portion of the movable valve body that comes into contact with the movable valve body.
Therefore, it is possible to prevent an axial force from being generated on the movable valve body due to the fluid pressure due to the difference in the pressure receiving area between the two, and to reduce the driving force on the movable valve body such as the biasing force of a spring. As a result, it is possible to downsize the solenoid section and the like.

Furthermore, the length of the movable valve body in the axial direction can be adjusted by forming a pair of divided members screwed together and coaxially connected to each other, so that the length of the movable valve body can be adjusted due to errors. It is possible to adjust the length in the direction and the stroke of the movable valve body.

Further, by adjusting the stroke of the movable valve body, the flow rate of the control fluid can be adjusted.

[Embodiment 1] FIG. 1 is a sectional view showing a switching valve which is an embodiment of the present invention.

The switching valve of this embodiment is a spool type electromagnetic valve, and consists of a valve section 1 and a solenoid section 20 (valve drive section) connected thereto.

The former valve portion 1 includes a valve body 2, and a cover 3 and a spacer 4 provided at both ends of the valve body 2. A first port 2a is located on one side (upper side in FIG. 1) of the outer peripheral surface of the valve body 2.
However, on the other side (lower side in FIG. 1) of the outer peripheral surface of the valve body 2, there are a second port 2b and a third port 2.
c are formed respectively.

Further, a shaft hole 6 having a circular cross section is formed in the center of the valve portion 1 and extends along the axial direction to the solenoid portion 20, and a tapered shape is formed on the inner peripheral surface of the shaft hole 6 halfway. A first valve seat 7 and a second valve seat 8 are respectively provided around the valve seat.

The first port 2a and the second port 2b are connected through the first valve hole 7a of the first valve seat 7, and the first port 2a and the third port 2c are connected through the second valve seat 8.
can be connected to each other through the second valve hole 8a.

A spool shaft (movable valve body) 9 is mounted in the shaft hole 6 so as to be movable along its axial direction.

The spool shaft 9 is formed by connecting a first divided member 10 and a second divided member 11 via a seal member S.

In the former first divided member 10, a through hole 10b having a female screw portion 10a is formed in the axial direction thereof. The latter second divided member 11 has a shaft portion 11a protruding from its large diameter portion in the axial direction, and on the distal end side thereof,
A male threaded portion 11b is formed. Then, this shaft portion 11a is inserted into the through hole 10b of the first divided member 10, and the male screw portion 11b and the female screw portion 10a are connected to each other.
and a lock nut 12 that is axially adjustable and screwed onto the distal end side of the male threaded portion 11b.
(adjustment member).

Further, the first divided member 10 and the second divided member 11 have a first seal member 10c and a second seal member 11c fitted in annular grooves on their respective outer peripheral surfaces, and their outer peripheral portions are It is structured to abut against the valve seats 7, 8 on the same side to close the valve holes 7a, 8a.

On the other hand, the outer circumferential surfaces of the first divided member 10 and the second divided member 11 on the outer end side are fitted with third and fourth seal members 2d, which are fitted into the annular grooves of both openings of the valve body 2.
2e are in sliding contact with each other, and both ends of the shaft hole 6 are closed by these third and fourth seal members 2d and 2e.

And the first and second seal members 10c, 11c
The diameter of the outer circumferential portion where the valve seats 7 and 8 come into contact, and the sliding contact portion where the third and fourth seal members 2d and 2e slide against the outer circumferential surfaces of the first and second divided members 10 and 11. The diameter is the same diameter, and the pressure receiving areas of both are the same size.

Note that the spool shaft 9 is urged toward the solenoid section 20 by a first spring 3a installed in the shaft hole 6 of the cover 3.

Here, the first divided member 10 and the second divided member 11
The spool shaft 9 is connected to the valve body 2 by screwing as described above, so the spool shaft 9 is attached to the valve body 2 in the following manner when the valve portion 1 is manufactured.

That is, first, the second divided member 11 with the second seal member 11c attached thereto is inserted into the shaft hole 6 of the valve body 2.
Insert it through one opening. After that, the first divided member 10 with the first seal member 10c attached thereto is inserted into the shaft hole 6 from the other opening. During this insertion, the shaft portion 11a of the second divided member 11 is inserted so as to pass through the through hole 10b of the first divided member 10. Next, the male screw portion 11b of the shaft portion 11a and the female screw portion 10a of the through hole 10b are screwed together. Then, a lock nut 12 is attached to the tip side of the male screw portion 11b.
Screw them together and tighten.

Moreover, since the first divided member 10 and the second divided member 11 are connected by the above-mentioned screwing, by rotating and moving one of them, the first and second seal members 10c and 11c can be separated. The distance between them can be adjusted.

Next, the solenoid section 20 will be explained.
A solenoid coil 22 is provided on the outer peripheral side of the inside of the frame 21 of the solenoid section 20 . The fixed core 23 is fitted halfway into the center hole of the solenoid coil 22, and the remaining portion of the center hole serves as a movable core hole 24.

The movable core hole 24 is the center hole 2 of the fixed core 23.
3a, and furthermore, the central hole 23a is
It communicates with the shaft hole 6. A push-up rod 25 is movably penetrated through the central hole 23a of the fixed core 23 along its axial direction.

One end of the push-up rod 25 is connected to the spool shaft 9 in a state of contact, and the other end extends to the movable core hole 24. A movable core 26 is provided in the movable core hole 24 so as to be movable along its axial direction. In the spring chamber 26a of the movable iron core 26,
A second spring 26b having a stronger urging force than the first spring 3a is housed.

The push-up rod 25 reaches a spring chamber 26a, and the flange at its tip is urged toward the valve portion 1 by a second spring 26b and is pressed against the internal opening end of the spring chamber 26a.

Next, the operation of this embodiment will be explained.

When the solenoid coil 22 is energized from the state shown in FIG. 1 when the solenoid section 20 is demagnetized, the movable iron core 26 resists the biasing force of the first spring 3a.
is moved to the left side in FIG. 1 and is attracted to the outer end surface of the fixed iron core 23. At this time, as the movable iron core 26 moves, the spool shaft 9 and the push-up rod 2
5 is moved to the left side in FIG. 1, the outer circumferential portion of the second seal member 11c abuts the second valve seat 8, and the second valve hole 8a is closed.

In this closed state, the first port 2a and the second port
port 2b is connected through the first valve hole 7a,
Fluid such as compressed air flows between the first port 2a and the second port 2b.

On the other hand, when the solenoid coil 22 is demagnetized, the movable core 26 is moved to the right side in FIG.
It is separated from the outer end surface of 3. Accompanying this movement of the movable iron core 26, the spool shaft 9 and the push-up rod 2
5 is moved to the right side in FIG. 1, the outer peripheral portion of the first seal member 10c abuts the first valve seat 7, and the first valve hole 7a is closed.

In this closed state, the first port 2a and the third
port 2c is connected through the second valve hole 8a,
Fluid such as compressed air flows between the first port 2a and the third port 2c.

When fluid such as compressed air flows in this way,
The first and second seal members 10c and 11c are the valve seat 7,
8 and the third and fourth seal members 2d and 2e are the first and second divided members 10 and 1.
The diameter of the sliding contact part that slides into contact with the outer peripheral surface of 1 is the same diameter, and the pressure receiving areas of both are the same size, so No axial force is generated on the spool shaft 9 due to the fluid pressure within the shaft hole. For this reason,
There is no need to increase the driving force for the spool shaft 9, such as the urging force of the first spring 3a, by the axial force when switching the flow, and it is possible to downsize the driving source such as the solenoid section 20. can.

Further, the spool shaft 9 is formed by connecting the first divided member 10 and the second divided member 11 by screwing together, so that the spool shaft 9 has the first seal portion 10c and the second divided member 11.
Since the distance between the spool shaft 9 and the seal member 11c can be adjusted, the flow rate flowing to the switching valve can be adjusted by adjusting the distance and adjusting the stroke of the spool shaft 9.

[Embodiment 2] FIG. 2 is a sectional view showing a switching valve according to another embodiment of the present invention.

The switching valve of the second embodiment has its second divided member 11
A distance adjusting member 27 is attached to the outer end surface of the third spring 2.
The movable iron core 26 is screwed and connected to the distance adjusting member 27, which is brought into contact with the urging force of the distance adjusting member 7a.

The stroke of the movable iron core 26 can also be adjusted by rotating the distance adjusting member 27 and moving it by a predetermined distance in the axial direction.

Note that the small diameter screw hole of the distance adjustment member 27 has a
A set screw 27b is screwed together. This set screw 27b is used to fix the position of the distance adjusting member 27 by rotating it after the distance adjusting member 27 has been rotated and moved by a predetermined distance.

Further, the third spring 27a moves the spool shaft 9 to the left side in FIG. 2 when the solenoid coil 22 is demagnetized.

As mentioned above, the present invention has been specifically explained based on the examples, but it goes without saying that the present invention is not limited to the above-mentioned examples and can be modified in various ways without departing from the gist thereof. Nor.

For example, in this embodiment, the outer circumference of the spool shaft 9 includes first and second seal members 10c and 11c.
Although the sealing member 10 is formed of
For example, the outer peripheral portion of the spool shaft 9 may be formed of the spool shaft 9 itself, and the valve seats 7 and 8 may be formed of a sealing member.

Furthermore, although the switching valve in this embodiment is a three-port electromagnetic valve, the number of ports and the operating force are not limited.

[Effect of idea]

According to the present invention, the following effects can be obtained.

(1) The movable valve body is composed of divided members that can be separated from each other in the axial direction, so that when manufacturing the valve, one of the divided members having the outer peripheral part such as the sealing member is inserted into the shaft hole, and the other is inserted into the shaft hole. After the seal member is inserted through the opening, the other divided member having an outer peripheral portion such as a seal member can be inserted into the shaft hole through the other opening, and the seal member can be assembled by screwing and connecting each other. There is no need for the trouble of installing the outer circumferential parts such as in the shaft hole, and therefore the valve can be easily assembled.

In particular, since the divided members are connected to each other by screwing, the valve can be easily assembled by this screwing connection.

In addition, since the movable valve body is formed by connecting the divided members by screwing them together, the number of parts can be reduced and the structure can be simplified, and from this point of view as well, the assembly of the valve can be facilitated. I can do it.

(2) By performing the assembly as described in (1) above,
The outer diameter of the movable valve body itself is formed to be larger than the inner diameter of the valve hole, so that the outer circumference of the movable valve body itself is sealed and the outer circumference of the movable valve body that comes into contact with the valve seat is separated. Since the pressure-receiving areas can be made the same size, it is possible to prevent the movable valve body from generating an axial force due to fluid pressure caused by a difference in the two pressure-receiving areas.

(3) With the effect of (2), it is possible to reduce the driving force for the movable valve body, such as the biasing force of a spring, and further downsize the solenoid portion.

(4) The length of the movable valve body in the axial direction can be adjusted by forming a pair of split members screwed together and coaxially connected to each other. The length in the axial direction and the stroke of the movable valve body can be adjusted.

Further, by adjusting the stroke of the movable valve body, the flow rate of the control fluid can be adjusted.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a switching valve as an embodiment of the present invention, and FIG. 2 is a sectional view showing a switching valve as another embodiment of the invention. 1... Valve part, 2... Valve body, 2a... First port, 2b... Second port, 2c... Third port,
2d... Third seal member, 2e... Fourth seal member, 3... Cover, 3a... First spring, 4
...Spacer, 6...Shaft hole, 7...First valve seat, 7
a...First valve hole, 8...Second valve seat, 8a...Second
Valve hole, 9...Spool shaft (movable valve body), 10...
First divided member, 10a...Female screw portion, 10b...
Through hole, 10c...First seal member, 11...Second divided member, 11a...Shaft portion, 11b...Male thread portion, 11c...Second seal member, 12...Lock nut (adjustment member), 20 ... Solenoid part (valve drive part), 21 ... Frame, 22 ... Solenoid coil, 23 ... Fixed iron core, 23a ... Center hole, 24 ... Movable iron core hole, 25 ... Push-up rod, 26 ... Movable iron core, 26a...Spring chamber, 26b...Second spring, 27...Distance adjustment member, 27a...Third spring, 27b...
Set screw, S...Sealing member.

Claims (1)

[Claims for Utility Model Registration] (1) A valve drive section, a valve section connected to this valve drive section, a shaft hole formed in this valve section, and a valve seat formed in this shaft hole. and a movable valve body disposed in the shaft hole so as to be movable along the axial direction thereof, and the movable valve body is brought into contact with and separated from a valve seat to open and close the valve hole. , the movable valve body is formed by a pair of divided members that are axially separable and are screwed together and coaxially connected to each other, and the length in the axial direction is adjusted by screwing the divided members together. A switching valve characterized in that: (2) The valve drive unit consists of a solenoid coil, a fixed iron core, and a movable iron core that is attracted to and separated from the fixed iron core by electromagnetic action, and that the axial length of the movable iron core is adjustable. A switching valve according to claim 1 of the claimed utility model registration.