JPH03113184A - Motor-driven type flow rate control valve - Google Patents

Abstract

PURPOSE:To obtain the simple structure by intensifying the magnetic force between a permanent magnet and a stator far from a valve seat and separating a needle valve step by step from the valve seat each time when the electric conduction direction to an electromagnetic coil is reversed. CONSTITUTION:A motor-driven flow rate control valve is constitute of a double seat type valve part V having valve seats 4 and 4' and a linear stepping motor part M. A plurality of permanent magnets 7a - 7d are arranged on a plunger 7 so that the S and N poles are arranged alternately and energized towards the valve seats 4 and 4' by a spring 17. Outside the plunger 7, a plurality of stators 14a magnetized by a DC electromagnetic coil 15 are arranged so that the pitch of the magnetic pole becomes equal to the magnet pitch of the permanent magnets 7, and the magnetic force between the permanent magnet 7 and the stator 14 is increased more as a needle valve 15 is separated further from the valve seats 4 and 4', and the needle valve 15 is separated from the valve seat step by step each time when the electric conduction direction to the electromagnetic coil 15 is reversed. Thus, the revolution motion of the needle valve is eliminated, and the simple structure can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric flow control valve used in a refrigeration system or the like.

[Conventional technology]

In electrically controlling the valve opening, a stepping motor with a rotor coaxially connected to the needle valve is used, and the needle valve is advanced or retreated along a guide member with a threaded portion according to the rotation angle of the rotor. There is a motor valve.

In addition, in an electromagnetic proportional valve, the position of the valve body is determined by the balance between the electromagnetic force according to the current and the spring force, and the opening degree of the valve is controlled.

Still another method is to use duty control by turning on and off a solenoid valve.

[Problem to be solved by the invention]

However, for those using stepping motors,
Since the rotation of the motor is converted into linear motion using a screw, the configuration becomes complicated and there is a limit to the cost reduction. In addition, since the electromagnetic proportional valve does not apply a brake to the valve body, it is easily affected by pressure fluctuations and temperature changes of the fluid, causing the position of the valve body to shift and the flow rate to change. Furthermore, controlling the solenoid valve by turning it on and off deteriorates the durability of the entire valve and causes problems of fluid vibration.

The present invention was made in view of the above facts, and provides a flow control valve that has a simple configuration, can prevent the valve body from shifting, does not deteriorate the durability of the entire valve, and does not cause fluid vibration. is intended to provide.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an electric flow rate control valve in which a needle valve is connected to an electromagnetically driven plunger, and the needle valve is brought into contact with and separated from a valve seat provided in a valve body. A plurality of permanent magnets are arranged along the valve so that N and S poles alternate, and a pressure spring is provided to bias the plunger toward the valve seat, and on the outside of the plunger,
A plurality of stators magnetized by a DC electromagnetic coil are arranged so that the pitch of the magnetic poles is equal to the pitch of the magnetic poles of the permanent magnet, and the magnetic force between the permanent magnet and the stator is made stronger as the distance from the valve seat increases. A configuration is adopted in which the needle valve is moved away from the valve seat one step at a time each time the direction of energization to the electromagnetic coil is reversed.

In this case, in order to facilitate the separation of the plunger from the valve seat, a driving spring may be provided on the valve seat side of the plunger. Further, in order to remove the urging force of the pressing spring when the valve is opened, an auxiliary plunger made of a magnetic material may also be provided.

In another configuration, a plurality of ribs are provided on the circumferential surface of the plunger to intersect with the direction of movement of the plunger, and a pressing spring is provided for urging the plunger toward the valve seat, and the outside of the plunger is , a plurality of stators are mounted in which at least one magnetic pole corresponds alternatively to the plurality of ribs, and the spacing between the ribs and the corresponding magnetic poles in each stator is set to be different from the pitch of the ribs, and each stator is arranged at a predetermined pitch. The needle valve is driven in the direction away from the valve seat one step at a time by magnetizing the needle valve in this order.

In another configuration, a plurality of permanent magnets are arranged on the plunger so that north and south poles alternate along the direction of movement of the plunger, and one of the plungers is biased toward the valve seat. A pressure spring is provided, and an auxiliary plunger made of a magnetic material is provided at a position facing the plunger of the pressure spring, and the other plunger is urged to move away from the valve seat with a weaker urging force than the pressure spring. A driving spring is provided, and a stator corresponding to the plurality of permanent magnets and a DC electromagnetic coil magnetizing the stator are provided on the outside of the plunger, and the auxiliary plunger is magnetized together with the stator and attracted to the plunger, and the stator is magnetized. A configuration is adopted in which the needle valve is moved away from the valve seat one step at a time each time the magnetic pole is reversed.

In yet another configuration, a plurality of ribs are provided on the circumferential side of the plunger so as to intersect with the direction of movement thereof, a pressing spring is provided on one side of the plunger for urging the plunger toward the valve seat, and the pressing spring is provided on one side of the plunger. An auxiliary plunger made of a magnetic material is provided at a position facing the plunger of the spring, and a driving spring is provided on the other side of the plunger to urge the plunger away from the valve seat with a weaker urging force than the pressing spring. The auxiliary plunger is provided with an electromagnetic coil that magnetizes the plunger, and a permanent magnet whose one magnetic pole corresponds to the plurality of ribs and the other magnetic pole corresponds between the ribs, and the electromagnetic coil is energized with a direct current. Then, the auxiliary plunger is magnetized and attracted to the plunger, and each time the energization direction is reversed, the magnetic pole in the plunger is reversed to move the needle valve away from the valve seat one step at a time.

〔Example〕

The present invention will be described in detail below with reference to the drawings. As shown in Fig. 1, the electric flow control valve of the present invention consists of a valve part V and a linear stepping motor part M, and this valve V adopts a so-called double seat type in which two valve seats are provided. are doing.

The valve body 1 of the valve part V is provided with a - crater 2 and a secondary port 3, and - two valve seats 4 on the upper and lower sides of the figure so as to sandwich the crater 2.
' and 4 are formed. The tapered end portion 5a of the needle valve 5 is in sliding contact with the lower valve seat 4, and the gap between the needle valve 5 and the valve seat 4 is changed to adjust the flow rate. On the other hand, the upper valve seat 4' comes into sliding contact with the intermediate portion 5b of the needle valve 5 to open and close the valve.

The needle valve 5 protrudes above the valve body 1 through a guide 6, and has a plunger 7 fixed to its upper end by a retaining ring 8, and is slidably inserted into a plunger tube 9 provided in a linear stepping motor M. be fitted.

This plunger tube 9 is a non-magnetic material, and the valve body 1
The linear stepping motor section M is connected to the valve body V in an airtight manner, and the upper end is also hermetically closed with MIO made of a non-magnetic material. and,
The upper space 11 of the upper valve seat 4' is connected to the secondary port 3 and the communication passage 1.
Further, the fluid passes through the guide 6 from the upper space 11 and enters the entire inside of the plunger tube 9 to equalize the pressure applied to the needle valve 5.

The plunger 7 is formed by stacking cylindrical permanent magnets 7a, 7b, 7c, and 7d as shown in FIG.
As shown in the figure, south poles and north poles are arranged alternately on the outside of each magnet.

An outer case 13 made of a magnetic material is attached to the lid 10 of the plunger tube 9, and a plurality of ring-shaped stators 14a are mounted on the side of the outer case 13 facing the plunger tube 9.
A composite stator 14 is provided, which is formed by stacking spacers 16 and spacers 16 alternately, and an electromagnetic coil 15 is fitted inside the outer case 13 and the composite stator 14. When the electromagnetic coil 15 is energized, each stator 14a becomes a ring-shaped electromagnet. On the other hand, the electromagnetic coil 15 has a monofilar winding or a bifilar winding, and depending on the direction in which the DC current flows, each stator 14
The S and N poles of a are changed.

Reference numeral 17 denotes a pressure spring, which is fitted between the plunger 7 and Mlo and urges the plunger 7 to be pushed downward in the figure.

FIG. 3 shows the permanent magnets 7a to 7d of the plunger 7 and the stator 14a in their zero positional relationship.
In (C), overlapping rectangles drawn on the right side indicate each permanent magnet 7a to 7d of the plunger 7,
The overlapping rectangular bands on the left side indicate overlapping stators 14a. As shown in FIG. 3, the length of the stator 14a is twice the pitch of the permanent magnets 7a to 7d. Also, plunger 7 and stator 1
4a, and the gap between the two is parallel to E.
x, and if the lower part is i2, then f2>pt, and the further away from the valve seat 4, the stronger the magnetic force between the plunger 7 and the stator 14a becomes.

Next, the movement of the plunger 7 will be explained. First, when the electromagnetic coil 15 is not energized, the plunger 7 is pushed down in the figure by the pressure spring 17, and the needle valve 5
The tapered end portion 5a of the valve contacts the valve seat 4 to close the valve.

FIG. 3(a) shows a state in which a current is passed through the electromagnetic coil 15 from one direction, and each stator 14a is magnetized with the polarity shown in the figure. Since the polarity of the magnet of the facing plunger 7 is opposite, they attract each other and are in a stable state.

FIG. 3(b) shows a state in which a current is passed through the electromagnetic coil 15 in a direction opposite to the one direction described above, and the polarities of the stator 14a are opposite and repel each other. However, due to the relationship 12>21, the magnetic force in the upper part of the figure is stronger, and the plunger 7 moves upward in the figure against the pressure spring 17, moving up one step and becoming stable as shown in Figure 3 (C). become a state.

As described above, each time the direction of energizing the electromagnetic coil 15 is changed, the plunger 7 rises one step at a time, the needle valve 5 rises, and the gap between the tapered tip 5a and the valve seat 4 is changed. The opening degree of the valve changes and the flow rate is controlled.

By programming the above-described energization order and inputting it to the control device, the flow rate can be controlled using a simple digital signal, and electronic control using a microcomputer becomes possible.

Note that in order to obtain the force that causes the plunger 7 to separate from the valve seat 4, the gap is set to a relationship of 12>fm.
A similar effect can be obtained by making the lower part weaker.

In the electric flow control valve shown in FIG. 4, an auxiliary plunger 18 made of a magnetic material is inserted between the plunger 7 and the pressing spring 17 in the plunger tube 9. Further, in place of the lid 10 at the upper end of the plunger tube 9, an attractor 19 made of a magnetic material is provided. The other configurations are similar to those shown in FIG.

Since the operation of the electric flow control valve shown in FIG. 4 is substantially the same as that shown in FIG. 1, the explanation will focus on the differences. First, when the electromagnetic coil 15 is energized, the auxiliary plunger 18 is attracted to the attractor 19, and the plunger 7 is released from the pressing force of the pressing spring 17.

Therefore, when the plunger 7 moves upward one step at a time, there is no need to resist the pressure spring 17, and the position of the plunger 7, that is, the flow rate can be controlled with low power.

When the electromagnetic coil 15 is de-energized, the auxiliary plunger 1
8 is biased by a pressing spring 17 and moves downward to press the plunger 7 downward in the figure until the retaining ring 8 of the plunger 7 comes into contact with the guide 6.

In FIG. 5, in addition to the configuration shown in FIG. 4, a drive spring 20 is fitted below the plunger 7, that is, between the plunger 7 and the guide member 6. The biasing force of the drive spring 20 is weaker than the biasing force of the pressing spring 17.

With this configuration, the permanent magnets 7a to 7 of the plunger 7
Even if there is no magnetic force between the drive spring d and the stator 14a, the drive spring 2
The plunger 7 can be lifted upwards by a force of 0. Therefore, the above-mentioned permanent magnets 7a to 7d,
Even if the vertical gaps 11 and 12 (see FIG. 3) between the stator 14a are made the same, the plunger 7 can be lifted upward by the force of the drive spring 20. As a result, it becomes possible to control the flow rate with even lower power than in the case of FIG. Furthermore, even in the configuration shown in Fig. 1 without the auxiliary plunger,
This drive spring 20 can be used.

In the electric flow control valve shown in FIG.
is not a magnet, but is made of magnetic material, and its outer periphery is
A plurality of grooves are bored perpendicular to the moving direction, and convex ribs 7e are formed at a constant pitch between each groove.

7f and 1g are formed.

Further, the upper end of the plunger tube 9 is closed with a lid lO, and a cylindrical upper lid 21 made of a non-magnetic material is attached to the lid 10 to cover the upper part of the plunger tube 9.

Below the upper lid 21 is a stator 13a that also serves as an outer case.
13b are arranged with a spacer 16 interposed therebetween. Electromagnetic coils 15a and 15b are incorporated inside the stators 13a and 13b, respectively. When these electromagnetic coils are energized from a power source (not shown), the stators 13a and 13b are magnetized, and the stators and the plunger are Each two end surfaces 1 in contact with the tube 9
3a1, 13a2 and 13b113b2, magnet N
A pole and a south pole will appear. It should be noted that both electromagnetic coils 15a and 15b may be monofilar wound since it is only necessary to magnetize the stator, and there is no need to change the current direction.

Adjacent magnetic poles 13a2.13 of stators 13a, 13b
As shown in FIG. 7, the pitch between the ribs 7 and bx is slightly thicker than the pitch of the ribs 7 formed on the plunger 7. 13bz are opposed to the rib-free portions of the plunger 7, respectively.

Next, to explain the operation, first, when the electromagnetic coil is not energized, the plunger 7 is pressed downward in the figure by the urging force of the pressing spring 17, and the tip tapered portion 5a of the needle valve 5 is pressed against the valve seat 4. The valve is closed by contacting the valve. At this time, the upper magnetic pole 13bt of the lower stator 13b is located at a position indicated by a chain line between the ribs 7e and 7f shown in FIG. 7(a) and slightly closer to 7f.

When the electromagnetic coil 15b is energized, the stator 13b is magnetized, and the magnetic pole 13b1 attracts the rib 7b closest to the plunger 7. This attractive force overcomes the force of the pressing spring 17, and the plunger 7 is pulled upward by one step, and the magnetic pole 13b1 is in a stable state at the position shown by the solid line.

Due to this movement of the plunger 7, the tip tapered portion 5a of the needle valve 5 opens by one step between it and the valve seat 4.

Next, when the electromagnetic coil 15a is also energized, the stator 13a is also magnetized as shown in the seventh axis).

Then, the magnetic pole 13a2 of the stator 13a attracts the nearest rib 7e, and as shown in FIG. 7(C), the rib 7e,
7f comes to the middle of the stator magnetic poles 13a2 and 13bt, and the magnetic force is balanced, and the plunger 7
The step is raised and a stable state is achieved.

Next, the power to the electromagnetic coil 15b is cut off, and as shown in FIG.
As shown in d), the stator 13b is demagnetized. The lower magnetic pole 13a2 of the upper stator 13a attracts the rib 7e, and the plunger 7 is pulled up by one step, as shown in FIG. 7(e).
Achieve the stable state shown in

Although not shown below, next are both stators 13a and 13b.
By magnetizing the plunger 7, the plunger 7 is pulled up by one step. Further, if only the stator 13b is magnetized, it will be raised by one step again, and the upper magnetic pole 13b1 of the lower stator 13b will be in a state corresponding to the rib 7c, and the valve will be in a fully open state.

As explained above, the needle valve 5 can be moved in six stages including the closed position, and the flow rate can be changed in five stages. In addition, to close the valve, electromagnetic coils 15a, 15
(The plunger 7 is connected to the pressing spring 17.)
The needle valve 5 is pushed down until it abuts against the guide 6, and the needle valve 5 closes the valve seats 4 and 4'.

The electric flow rate control valve shown in FIG. 8 is roughly the same as that in FIG. 6, but here it is an outer case 13a.

13b does not serve as a stator, but stators 22a and 22b facing the plunger tube 9 are provided separately from this outer case. And each stator 22a, 22b is connected to 22as, 22a2 and 22bt by a spacer 16'.
It is divided into upper and lower parts like 22bz. Furthermore, among these, 22a2 and 22bs have protrusions 23a,
23b is formed, and the plunger tube 9 is passed through the plunger tube 9 to be close to the plunger 7. With such a configuration, magnetic resistance can be reduced and magnetic force can be strengthened, making it possible to save power.

The opening and closing operations of this valve are similar to those in the embodiment shown in FIG.

In FIG. 9, two ribs 7a formed on the plunger 7 are shown.
, 7b and the narrow diameter portion 7d formed above these are formed such that the outer diameter thereof becomes gradually thinner as the portion is located upward. With this configuration, it is possible to create a difference in magnetic resistance between the magnetic poles 13a2 y13bs of the stator and the plunger 7, and it is possible to strengthen the force for pulling the plunger 7 upward.

The operation of the example shown in FIG. 9 will be explained. Electromagnetic coil 15a
, 15b are not energized, the biasing force of the spring 17 pushes the plunger 7 downward until it comes into contact with the guide 6, and the valve is closed.

Next, when the electromagnetic coil 15a is energized, the stator 13a is magnetized as shown in FIG. 10(a), and the magnetic pole 13a1
and 13a2 attract the opposing portions of the plunger 7, but no vertical suction force is generated, resulting in a stable state.

Next, when the electromagnetic coil 15b is also energized, the stator 13b is also magnetized, as shown in FIG.
3b1 sucks the rib 7b. Here, electromagnetic coil 15
When the energization of a is cut off and the stator 13a is demagnetized, the plunger 7 is pulled up against the pressure spring 17 and the first
A stable state is reached when the temperature rises by one step as shown in Figure 0 (C).

Next, the electromagnetic coil 15a is energized again, and the stator 13a
When magnetized, the magnetic pole 13a as shown in FIG. 10(d)
2 sucks the rib 7e. When the electromagnetic coil 15b is deenergized and the stator 13b is demagnetized, the plunger 7 is pulled up against the spring 17, as shown in Fig. 1O(e).
A stable state is reached when the value increases by one step.

As described above, each time the plunger 7 moves up one step, the valve changes its opening degree and the flow rate is adjusted.

In the embodiment shown in FIG. 11, the upper and lower ends 71 of the plunger 7,
A tapered portion is formed at 7j. With this configuration, the upward force of the plunger 7 can be increased.

The configuration example of the invention shown in FIG. 12 employs an auxiliary plunger 17 and a drive spring 20, similar to the configuration example shown in FIG. 5, and has many features in common. The first difference is that the stator is divided into upper and lower parts 14b and 14c. Second,
The plunger 7 is provided with ring-shaped permanent magnets 23a to 23d at regular intervals as shown in FIG. 13, and each adjacent magnet has an outermost N and S pole as shown in FIG. They are arranged alternately.

Next, the operation of FIG. 12 will be explained. Electromagnetic coil 15
When the valve is not energized, the force of the pressing spring 17 is greater than the force of the driving spring 20, and the plunger 7 is pushed downward in the figure until it hits the guide 6, thereby closing the valve.

When the electromagnetic coil 15 is energized, the auxiliary plunger 18 is magnetized, compresses the pressure spring 17 and attracts the plunger 7, and is released from the pressure force of the pressure spring 17 during plunging. Further, due to this attraction, a magnetic circuit is formed by the stator 14b, the auxiliary plunger 18, the plunger 7, the stator 14c, and the outer case 13, and the stator 14c is magnetized. At this time, as shown in FIG. 14(a), the stator 14
If the magnetic pole facing the plunger 7 of c is the north pole, the outer magnetic pole of the magnet 23a at the top of the plunger 7 is the south pole, so no axial force is applied to the plunger 7, resulting in a stable state. .

When the direction of energization of the electromagnetic coil 15 is reversed, the magnetic pole of the stator 14c becomes the S pole as shown in FIG. Then, due to the urging force of the drive spring 20, the plunger 7 is pushed upward in the figure, and as shown in FIG.
Move as one step until it faces the north pole of.

In this way, by changing the direction of energization to the electromagnetic coil 15, the plunger 7 reverses its magnetic pole and moves up one step at a time, changing the degree of opening of the valve.

When moving the plunger 7 downward, the power to the electromagnetic coil 15 is cut off. The auxiliary plunger 18 is demagnetized, moves away from the plunger 7, and comes into contact with the lid 10. Then, the plunger 7 is pushed downward by the stretching force of the pressing spring 17, and the tapered tip portion 5a of the needle valve 5 comes into pressure contact with the valve seat 4, thereby closing the valve.

By programming the above-described energization order and inputting it to the control device, the flow rate can be controlled using a simple digital signal, and electronic control using a microcomputer becomes possible.

Note that a shaded coil 18a is formed on the surface of the auxiliary plunger 18 facing the plunger 7, and the electromagnetic coil 1
There is a delay in demagnetizing the auxiliary plunger 1B at the moment when the direction of energization to the auxiliary plunger 1B is switched.
The auxiliary plunger 1B is prevented from separating from the plunger 7.

In the configuration example of the invention shown in FIG.
is connected to the needle valve 5 by a retaining ring 8. A large number of grooves 7m are bored on the outer periphery of the plunger 7 so as to be perpendicular to the direction of movement, and convex ribs 7k are formed at a constant pitch between the grooves 7m. On the other hand, the auxiliary plunger 18 has a protrusion at its lower end, which is formed to fit into a conical recess formed in the plunger 7 to increase suction force.

In addition, the outer case 13 extends below the left and right sides of the electromagnetic coil 15, and two permanent magnets 2 are placed at the top and bottom of the left and right extensions.
4 is provided. Permanent magnet 2 used here
4 has a cylindrical shape as shown in FIG. 16, and the N and S poles are formed on the upper and lower end faces. A magnetic body is provided at both ends of these permanent magnets 24, and the N pole 24a of the permanent magnet is
, forming the S pole 24b.

When the electromagnetic coil 15 is not energized, the pressing spring 17
Since the biasing force of is stronger than the biasing force of the drive spring 20, the needle valve 5 is pushed down in the figure and comes into contact with the valve seat 4 to be in the closed state.

When the electromagnetic coil 15 is energized, the auxiliary plunger 18 is attracted to the plunger 7, and at the same time, the plunger 7 is magnetized and the plunger 7 is released from the urging force of the pressing spring 17. At this time, the plunger 7 and both magnetic poles 24a, 24
b is the state shown in FIG. 17(a). That is, one N pole 24a faces the rib 7 at the top of the plunger 7, and the other S pole 24b faces between the lower ribs of the plunger 7, that is, the groove 7m. Since the plunger 7 has the south pole, it is stable in the state shown in FIG. 17(a).

Next, when the direction of energization of the electromagnetic coil 15 is changed, the plunger 7 is reversed to the north pole as shown in FIG. 17(c). Therefore, it becomes the same polarity as the opposing N-pole 24a and repels each other.

At this time, the plunger 7 moves upward in the figure by the biasing force of the drive spring 20, and moves as one step until the lower S pole 24b faces the next rib 7 immediately below. It reaches the stable state shown in Figure (C) and stops.

As described above, each time the direction of energization of the electromagnetic coil 15 is switched, the plunger 7 moves up one step at a time, changing the opening degree of the valve.

To move the plunger 7 downward in the figure, the electromagnetic coil 15 is de-energized. By doing this, the auxiliary plunger 18 is demagnetized and separated from the plunger 7, the plunger 7 is moved downward in the figure by the biasing force of the pressing spring 17, and the needle valve 5 is pressed against the valve seat 4 to close the valve. Ru.

〔Effect of the invention〕

As explained above, in the present invention, since rotational motion is not used to drive the needle valve, the structure of the electric flow control valve is extremely simple, and manufacturing costs can be reduced.

Furthermore, since the position of the needle valve is held by magnetic force, the flow rate can now be controlled without being affected by fluid pressure fluctuations.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing the configuration of the electric flow control valve of the present invention, FIG. 2 is a perspective view showing the configuration of the permanent magnet provided in the plunger, and FIGS. A diagram explaining the moving state of the plunger in the configuration example shown in FIG. 1, FIG. 4 is a vertical cross-sectional view of a configuration example using an auxiliary plunger, FIG. 5 is a vertical cross-sectional view of a configuration example using a drive spring, and FIG. 6 7(a) to (e) are diagrams explaining the state of movement during the plunge shown in FIG. 6. FIG. 8 shows the stator passing through the plunger tube. FIG. 9 is a longitudinal sectional view of a configuration example in which the outer diameter of the rib formed on the plunger is changed, and FIGS. 10(a) to (e) are FIG. 9. FIG. 11 is a longitudinal cross-sectional view of a configuration example in which tapered portions are formed at both ends of the plunger. Fig. 12 is a longitudinal cross-sectional view of a configuration example in which the stator is divided and a permanent magnet is provided in the plunger, Fig. 13 is a perspective view of a permanent magnet provided in the plunger, and Fig. 14 shows the effect of the configuration example in Fig. 12. Diagram to explain, 1st
Figure 5 is a longitudinal sectional view of a configuration example using a permanent magnet instead of the stator, Figure 16 is a perspective view of a permanent magnet provided outside the plunger, and Figure 17 explains the operation of the configuration example of Figure 15. This is a diagram. 1... Valve body, 4... Valve seat, 5... Needle valve,
7... Plunger, 7a-7d, 23... Permanent magnet, 13a, 13b, 14a, 22a, 22b... Stator, 15. 15a, 15b... Electromagnetic coil, 17...
...Press spring, 18...Auxiliary plunger, 19...
Attractor, 20... Drive spring, 24... Permanent magnet (provided on the outside of the plunger). Figure 2 (0) (b) (C) Figure 3 Figure 5 Figure 8 Figure 3 Figure 11 Figure 13 (0) (b) (C) Figure 14

Claims (8)

[Claims] (1) In an electric flow control valve in which a needle valve is connected to an electromagnetically driven plunger and is brought into contact with and separated from a valve seat provided in the valve body, a plurality of permanent magnets are attached to the plunger along the direction of movement of the needle valve. , S poles are arranged alternately, and a pressing spring is provided to urge the plunger toward the valve seat, and a plurality of stators magnetized by a DC electromagnetic coil are arranged on the outside of the plunger. The needle valve is arranged so that the pitch is equal to the pitch of the magnetic poles of the permanent magnet, and the magnetic force between the permanent magnet and the stator is made stronger as the distance from the valve seat increases. 1
An electric flow control valve that is separated from the valve seat in steps. (2) In an electric flow control valve in which a needle valve is connected to an electromagnetically driven plunger and is brought into contact with and separated from a valve seat provided in the valve body, a plurality of permanent magnets are attached to the plunger along the direction of movement of the needle valve. , S poles are arranged alternately, and a pressing spring is provided to urge the plunger toward the valve seat, and a plurality of stators magnetized by a DC electromagnetic coil are arranged on the outside of the plunger. A driving spring is arranged so that the pitch is equal to the pitch of the magnetic poles of the permanent magnet, and a driving spring is provided on the valve seat side of the plunger to bias the plunger in a direction away from the valve seat with a biasing force weaker than the pressing spring, and the electromagnetic An electric flow control valve characterized in that the needle valve is moved away from the valve seat one step at a time each time the direction of energization to the coil is reversed. (3) The electric flow rate control valve according to claim 1 or 2, wherein an auxiliary plunger made of a magnetic material is fitted between the pressing spring and the plunger, and the auxiliary plunger of the pressing spring is opposed to the auxiliary plunger. 1. An electric flow control valve characterized in that an attractor is provided at a position, and when the DC electromagnetic coil is energized, the auxiliary plunger is attracted to the attractor. (4) In an electric flow control valve in which a needle valve is connected to an electromagnetically driven plunger and is brought into contact with and separated from a valve seat provided on the valve body, a plurality of ribs are provided on the circumferential surface of the plunger to intersect with the moving direction of the plunger. A pressing spring is provided that stands upright and biases the plunger toward the valve seat, and a plurality of stators are attached to the outside of the plunger, at least one of the magnetic poles of which corresponds alternatively to the plurality of ribs. The distance between the ribs and the corresponding magnetic poles in each stator is set to be different from the pitch of the ribs, and each stator is magnetized in a predetermined order, thereby driving the needle valve one step at a time in the direction away from the valve seat. An electric flow control valve characterized by: (5) The electric flow control valve according to claim 4, wherein the outer diameter of the plurality of ribs formed on the circumferential surface of the plunger becomes smaller as the distance from the valve seat increases. type flow control valve. (6) The electric flow control valve according to claim 4 or 5, characterized in that the plunger has tapered portions formed near both ends thereof, the diameter of which decreases as the distance from the valve seat increases. (7) In an electric flow control valve in which a needle valve is connected to an electromagnetically driven plunger and is brought into contact with and separated from a valve seat provided in the valve body, a plurality of permanent magnets are attached to the plunger along the direction of movement of the needle valve. , the S poles are arranged alternately, a pressure spring is provided on one side of the plunger to urge the plunger toward the valve seat, and an auxiliary plunger made of a magnetic material is provided at a position facing the plunger of the pressure spring. A driving spring is provided on the other side of the plunger to urge the plunger away from the valve seat with a weaker urging force than the pressing spring, and a stator corresponding to the plurality of permanent magnets is provided on the outside of the plunger. A DC electromagnetic coil that magnetizes the stator is provided, and an auxiliary plunger is magnetized together with the stator and attracted to the plunger, and the needle valve is moved away from the valve seat one step at a time each time the magnetic pole of the stator is reversed. Electric flow control valve. (8) In an electric flow control valve in which a needle valve is connected to an electromagnetically driven plunger and is brought into contact with and separated from a valve seat provided in the valve body, a plurality of ribs are provided on the circumferential surface of the plunger, intersecting the direction of movement thereof. is set upright, a pressure spring is provided on one side of the plunger to urge the plunger toward the valve seat, and an auxiliary plunger made of a magnetic material is provided on the pressure spring at a position facing the plunger, and the other side of the plunger is provided with a pressure spring that urges the plunger toward the valve seat. A driving spring is provided on the outside of the plunger to urge the plunger away from the valve seat with a weaker urging force than the pressing spring.
An auxiliary plunger, an electromagnetic coil that magnetizes the plunger, and a permanent magnet whose one magnetic pole corresponds to the plurality of ribs and whose other magnetic pole corresponds between the ribs, and when the electromagnetic coil is energized with direct current, the auxiliary plunger is magnetized. An electric flow control valve characterized in that the plunger is magnetized and attracted to the plunger, and each time the direction of energization is reversed, the magnetic pole of the plunger is reversed to move the needle valve away from the valve seat one step at a time.