CN108071841B - A kind of normal-open electromagnetic valve - Google Patents

Abstract

The present invention provides a kind of normal-open electromagnetic valve, can reduce valve closing difficulty, improves valve opening performance.The present invention includes the spool for opening and closing valve port, the spool is connected with the electromagnetic part for driving its valve closing and the returning spring for keeping it in valve opening working position, the returning spring includes the second spring that the first spring and stiffness factor are greater than first spring, and the two forms effect end when valve closing with one end of the respective separate valve port；On valve closing direction, the effect end of first spring is in front of the effect end of the second spring, and so as in valve closing, the electromagnetic part pushes the spool by after the first spring-compressed predetermined amount, then compresses the second spring.Form using the above structure can effectively take into account valve opening performance and valve closing reliability, have biggish valve opening retentivity, can satisfy the demand of books circulation amount.

Description

A kind of normal-open electromagnetic valve

Technical field

The present invention relates to Solenoid Valve Technology fields, more particularly to a kind of normal-open electromagnetic valve.

Background technique

Normal-open electromagnetic valve refers to that solenoid valve is closed when coil is powered, the solenoid valve that solenoid valve is opened after coil blackout, when Solenoid valve in pipeline select normal-open electromagnetic valve when opening, closing for a long time once in a while.

Referring to FIG. 1, Fig. 1 is a kind of structural schematic diagram of typical normal-open electromagnetic valve in the prior art.

As shown in Figure 1, in the prior art, solenoid valve includes valve body 1 ', spool 2 ' and a returning spring 3 ', valve body 1 ' has There is a valve port 4 ', spool 2 ' is for opening and closing valve port 4 ', and under normality, coil blackout, spool 2 ' is only by returning spring 3 ' towards valve opening Power is supported in direction, and then is maintained at valve opening working position；When needing close port 4 ', coil on-off, electromagnetism power drive spool 2 ' move downward, and then compression reaction spring 3 ', overcome spring force and close port 4 ', and because of returning spring after coil blackout 3 ' restoring force and return to valve opening working position.

According to the characteristic of spring, to reach good valve opening performance, it is necessary to which the restoring force of 3 ' valve opening of returning spring is enough Greatly, it is also required to sufficiently large electromagnetic force when on the contrary, closing, to make in the prior art, the volume of coil and valve body 1 ' is equal It is larger, coil higher cost.

Therefore, it needs to design a kind of normal-open electromagnetic valve, to take into account the convenience of valve opening performance and valve closing, reduces cost.

Summary of the invention

The object of the present invention is to provide a kind of normal-open electromagnetic valves, can reduce valve closing difficulty, improve valve opening performance.

To achieve the above object, the present invention provides a kind of normal-open electromagnetic valves, including the spool for opening and closing valve port, institute It states spool and is connected with the electromagnetic part for driving its valve closing and the returning spring for keeping it in valve opening working position, the returning spring packet It includes the first spring and stiffness factor is greater than the second spring of first spring；On valve closing direction, the electromagnetic part pushes institute Spool is stated by after the first spring-compressed predetermined amount, then compresses the second spring.

Normal-open electromagnetic valve of the invention, returning spring include that lesser first spring of stiffness factor and stiffness factor are larger Second spring, when valve closing, electromagnetic part pushes spool to compress the first spring first, after the first spring-compressed predetermined amount, just with The effect end in contact of second spring, and then the first spring and second spring are compressed simultaneously.

Electromagnetic part includes magnetic opposite dynamic iron core and static iron core, and when needing valve closing, electromagnetic coil is powered, so that dynamic Iron core generates magnetism, and moves under the attraction of static iron core towards static iron core, to drive spool to move to valve closing direction, that is, It says, during valve closing, the spacing of dynamic iron core and static iron core is gradually reduced；Due to the initial stage of valve closing, electromagnetic force is relatively It is weak, then the first bullet can be overcome using lesser electromagnetic force by lesser first spring of electromagnetism power drive stiffness factor first The elastic force of spring and drive valve core movement；And when valve core movement is to the position abutted with the biggish second spring of stiffness factor, Due to the Distance Shortened of dynamic iron core and static iron core magnetive attraction is largely increased, it is sufficient to further overcome the bullet of second spring Property power realize that reliable valve closing also improves valve closing reliability to not only reduce the difficulty of valve closing.

And when needing valve opening, the power supply of electromagnetic coil is cut off, the magnetic of dynamic iron core disappears, and spool is no longer influenced by electromagnetic part Compress effect, but the first spring at this time and second spring all have biggish decrement, collectively face towards valve opening position promotion Spool so that spool fast and stable open valve port, and be maintained at valve opening position by the first spring and second spring, have Good valve opening performance.

As it can be seen that present invention form using the above structure, can effectively take into account valve opening performance and valve closing reliability, have larger Valve opening retentivity, can satisfy the demand of books circulation amount；And, it is only necessary to the first spring and second spring are rationally matched It sets, no need to increase for driving the electromagnetic coil volume of electromagnetic part, without valve volume is expanded, so that solenoid valve is kept The structure and lesser volume simplified, can save cost and installation space.

When optionally, first spring and the second spring form valve closing with one end of the respective separate valve port Act on end；On valve closing direction, the effect end of first spring is in front of the effect end of the second spring.

It optionally, further include that retaining piece bullet is pressed between the effect end of the second spring and the electromagnetic part, and is had There is barrier in the barrier portion in spool valve closing path；When the spool is by the first spring-compressed predetermined amount, move to The position of the barrier portion is pressed, and then the second spring is compressed by the barrier portion.

Optionally, the retaining piece is tubular retaining ring, the effect of the first end and the second spring of the tubular retaining ring End abuts, and inwardly prolongs to form protrusion at least part diameter, as the barrier portion, the second end of the tubular retaining ring and institute State electromagnetic part abutting.

Optionally, in a ring, first spring pocket is loaded on outside the spool, and the spool is far from described for the barrier portion One end of valve port has the flange part that abuts with first spring, and the barrier portion is with the hollow cavity receiving of its inner ring described the One spring and the spool, annular entity portion with the flange part for abutting.

Optionally, the second spring includes along the circular spring body of axial screw and being connected to described spring body one end End, effect end of the end as the second spring.

It optionally, further include the stop washer with the first stopper section and the second stopper section, first stopper section and institute It states the first spring to abut towards one end of the valve port, second stopper section and the second spring are towards the one of the valve port End abuts.

Optionally, the stop washer is cylindrical in shape, and forms first stopper section with an axial end face, the other end At least part extends radially outward, and forms second stopper section.

Optionally, the stop washer is set in outside the spool, and is connected by second stopper section and valve body, institute Second spring is stated to be set in outside the stop washer.

Optionally, in a ring, the stop washer is equipped with and the inner ring of second stopper section for second stopper section The notch section of hollow cavity connection.

Optionally, the electromagnetic part includes the dynamic iron core and static iron core of magnetic attraction, and provides magnetic for the dynamic iron core The electromagnetic coil of power, the dynamic iron core are connect with the spool.

Detailed description of the invention

Fig. 1 is a kind of structural schematic diagram of typical normal-open electromagnetic valve in the prior art；

Fig. 2 is the schematic diagram of the section structure of normal-open electromagnetic valve provided by the present invention in a specific embodiment；

Fig. 3 is the partial enlargement diagram of part A under normal-open electromagnetic valve original state shown in Fig. 2；

Fig. 4 is the partial enlargement signal of part A when normal-open electromagnetic valve valve closing shown in Fig. 2 is in the first stage in the process Figure；

Fig. 5 is the partial enlargement signal of part A when normal-open electromagnetic valve valve closing shown in Fig. 2 is in second stage in the process Figure；

Fig. 6 is the relation schematic diagram of electromagnetic force and spring force.

In Fig. 1:

Valve body 1 ', spool 2 ', returning spring 3 ', valve port 4 '；

In Fig. 2-6:

Valve port 1, spool 2, flange part 21, electromagnetic part 3, dynamic iron core 31, static iron core 32, returning spring 4, the first spring 41, First effect end 411, second spring 42, spring body 421, end 422, second act on end 423, retaining piece 5, barrier portion 51, stop Washer 6, the first stopper section 61, the second stopper section 62, notch section 63, valve body 7.

Specific embodiment

The present invention provides a kind of normal-open electromagnetic valves, can reduce valve closing difficulty, improve valve opening performance.

Below in conjunction with attached drawing, the present invention is specifically introduced, so that those skilled in the art's accurate understanding is of the invention Technical solution.

As described herein first, second, only for distinguishing more than two same or similar structures or component, do not indicate To the particular determination of setting sequence.

Axial direction as described herein refers to the extending direction of spool 2, it is understood that is spool 2 during valve opening and valve closing The direction of motion；Radial direction as described herein be to axial for, in in axially vertical face；It is as described herein inside and outside Using the central axes of spool 2 as reference, radially, the direction close to 2 central axes of spool is interior, the side far from 2 central axes of spool To outside being.

As shown in Fig. 2, the present invention provides a kind of normal-open electromagnetic valve, including valve body 7, spool 2, electromagnetic part 3 and reply Spring 4, wherein valve body 7 can connect entrance sleeve and discharge connection, and is equipped with and connects for being connected to the entrance sleeve and outlet The valve port 1 of pipe, spool 2 to change the connected relation of entrance sleeve and discharge connection, and then realize refrigeration for opening and closing valve port 1 Whether the circulation of the media such as agent, gas, oil；Under normality, the valve port 1 of normal-open electromagnetic valve of the invention is in the open state, valve Core 2 is responded the support of spring 4 and supports and be maintained at valve opening working position；When needing close port 1, electromagnetic part 3 is in magnetive attraction Effect is lower to push spool 2 to move towards valve closing direction, so that spool 2 overcomes the elastic force of returning spring 4 to move to closing valve The position of mouth 1, and then valve port 1 is closed, that is to say, that spool 2 can directly or indirectly be connect with electromagnetic part 3, so that Electromagnetic part 3 can act on spool 2, to drive 2 close port 1 of spool.

In the present invention, electromagnetic part 3 can specifically include dynamic iron core 31, static iron core 32 and electromagnetic coil, and electromagnetic coil is powered When generate magnetic field, dynamic iron core 31 is magnetized so that dynamic iron core 31 have with the magnetic opposite magnetic force of static iron core 32, and then in magnetism It is moved under the action of attraction close to static iron core 32, and the direction of this movement is just consistent with the valve closing direction of spool 2, i.e., it is dynamic When iron core 31 is moved towards static iron core 32, spool 2 can be driven and moved towards valve closing direction.When electromagnetic coil power-off, iron is moved Core 31 just loses magnetism power, and then no longer attracts each other with static iron core 32, would not also apply spool 2 towards valve closing direction and transport Dynamic driving force, returning spring 4 is restorable, and then spool 2 is pushed to be returned to valve opening working position.Dynamic iron core 31 herein and quiet Iron core 32 is for valve body 7, and static iron core 32 is fixed on valve body 7, and dynamic iron core 31 can be axially moved in valve body 7.

In the present invention, returning spring 4 may include the first spring 41 and second spring 42, the stiffness factor of the first spring 41 Smaller, the stiffness factor of second spring 42 is larger, is greater than the first spring 41, also, be both at compressive state as valve Core 2 is towards one end of electromagnetic part 3 and towards between one end of valve port 1, and on valve closing direction, electromagnetic part 3 pushes spool 2 will first First spring 41 compresses predetermined amount, just acts on second spring 42 later.

Specifically, making when the one end of the first spring 41 and second spring 42 far from valve port 1 forms valve closing with 2 phase of spool Effect end is the first effect end 411 with the effect end of the first spring 41, is the second effect with the effect end of second spring 42 End 423, then on valve closing direction, the first effect end 411 is in front of the second effect end 423, then, during valve closing, electricity When magnetic portion 3 drives spool 2 to move towards valve closing direction, spool 2 acts on the first effect end 411 first, further compresses first Spring 41, and when the first spring 41 is compressed predetermined amount, the position being in contact with the second effect end 423 is just moved to, in turn Second spring 42 is further compressed together, the elastic force of the first spring 41 and second spring 42 is finally overcome and moves to The position of close port 1.

Using normal-open electromagnetic valve of the invention, due to the initial stage in valve closing process, dynamic iron core 31 and static iron core 32 away from From farther out, magnetic attracting force between the two is weaker, then, at valve closing initial stage, solenoid valve overcomes stiffness factor lesser first First spring 41, and then spool 2 can relatively easily be pushed to move towards valve closing direction, to reduce the driving difficulty of valve closing, Without using biggish electromagnetic coil to provide enough driving forces, reduce costs, and valve body 7 is without electric to adapt to Magnetic coil and use large volume structure type save installation space to simplify the structure of valve body 7.

Meanwhile with the further movement of spool 2, dynamic iron core 31 is increasingly closer to static iron core 32, and electromagnetic part 3 is capable of providing Stronger electromagnetic force, to drive spool 2 to execute valve closing movement；When the first spring 41 is by compression predetermined amount, spool 2 move to The position that the biggish second spring 42 of stiffness factor abuts against, and then the first spring 41 and second spring 42 are compressed simultaneously, finally Reliably spool 2 is driven to valve closing position, is able to maintain the reliability of valve closing.

When needing valve opening, electromagnetic coil power-off, dynamic iron core 31 loses magnetism therewith, and electromagnetic part 3, which also just no longer has, supports Pressure valve core 2 is to close the magnetic action power of valve port 1, and the first spring 41 and second spring 42 at this time all has biggish compression Amount, the elastic-restoring force that the two generates push spool 2 towards valve opening position, it is sufficient to drive spool 2 to reply and be maintained at valve opening work Make position.That is, being matched using the first spring 41 and second spring 42, normal-open electromagnetic valve of the invention also has preferably Valve opening performance, and valve opening retentivity is larger, can satisfy the demand of books circulation amount.

As shown in figure 3, the present invention can also include retaining piece 5, which is suppressed in the second effect end 423 and electromagnetism It between portion 3, can specifically be pressed between the second effect end 423 and the static iron core 32 of electromagnetic part 3, with static iron core 32 towards valve port 1 side end face abuts, and since second spring 42 is in compressive state, retaining piece 5 is compressed towards valve opening position, so that retaining piece 5 by elastic compression between second spring 42 and static iron core 32.

The retaining piece 5 can have barrier in the barrier portion 51 in 2 valve closing path of spool, and on valve closing direction, the barrier Portion 51 is in after the first effect end 411, when the first spring 41 is compressed predetermined amount by spool 2, is just moved to and the barrier The position that portion 51 axially abuts, and then the barrier portion 51 is compressed towards valve closing direction, and power will be compressed via the barrier portion 51 and passed Second spring 42 is passed, second spring 42 is compressed by the barrier portion 51.

In a kind of specific set-up mode, retaining piece 5 is specifically as follows tubular retaining ring, the axial ends point of the tubular retaining ring First end and second end is not defined as it, wherein first end is abutted with the second effect end 423 of second spring 42, and at least one The radially inwardly extending formation protrusion in part, as above-mentioned barrier portion 51；Second end is abutted with electromagnetic part 3, is specifically as follows A side end face of static iron core 32 towards valve port 1 abuts against in electromagnetic part 3.

In other words, retaining piece 5 can be the structure type of sleeve-shaped, be sleeved on the outside of the first spring 41 and spool 2, And it is equipped with end cap in one end of the sleeve, which can be annular end cap, and be in sleeve wall radially inner side with annular end cap Part as barrier portion 51, barrier portion 51 at this time in a ring, and accommodates the first spring 41 and spool with the hollow cavity of inner ring 2, and outer ring portion is connected as one with sleeve wall；The end cap forms barrier face towards the end face of valve port 1, with the second effect End 423 abuts against, as shown in Figure 3.

In conjunction with Fig. 4 and Fig. 5, in the present invention, the first spring 41 can be specifically set with outside spool 2, and spool 2 can be separate One end of valve port 1 forms flange part 21, which can be extended radially outward by the outer wall of spool 2, Neng Gouyu First effect end 411 abuts against；Retaining piece 5 can be sleeved on except the first spring 41 and spool 2, and to be in its barrier portion 51 The hollow cavity of inner ring accommodates spool 2 and the first spring 41, and using the annular entity portion of barrier portion 51 as with flange part 21 positions abutted against, so as to when flange part 21 is moved to 51 corresponding position of barrier portion, by the reality of barrier portion 51 Body ring part compresses barrier portion 51.

In addition, second spring 42 may include along the circular spring body 421 of axial screw and being connected to the spring body 421 The end 422 of one end, which acts on end 423 as the second of second spring 42, for abutting with retaining piece 5.At this point, Since the size at the second effect end 423 is less than the spring body 421 of second spring 42, so that the second effect end 423 and spring body 421 Between there is certain radial clearance, end 422 may be at the part close to radial outside, and then the outside with retaining piece 5 Edge abuts against, and avoids generating interference with second spring 42 too close to inside.

Especially, the first spring 41 and second spring 42 can be set gradually in the axial direction, on valve closing direction, the first bullet Spring 41 substantially connects in the axial direction with second spring 42, and there is no the parts to overlap, and radially, the first spring 41 exists Interior, outside, there are certain radial clearances for the two for second spring 42；On the one hand, in the axial direction, the two, which cooperates, generates to valve Core 2 supports power, and can be arranged using shorter length, and without the entire axial action in spool 2, but concentration acts on One section in 2 axial direction of spool, so that axial force is more concentrated and stablized, it will not substantially generate radial skew； On the other hand, the two is mutually indepedent radially, avoids interfering.

End 422 can for circumferentially around retaining ring, to be come into full contact with retaining piece 5, drop stress concentration；Also It can be the structure types such as baffle.

On the basis of the above, the present invention can also include stop washer 6, which specifically can be fixed with valve body 7 Connection, limits for one end to the first spring 41 and second spring 42 towards valve port 1；Specifically, stop washer 6 wraps The first stopper section 61 and the second stopper section 62 are included, the first stopper section 61 is abutted with one end of the first spring 41 towards valve port 1, and court The first spring 41 is supported to valve opening position, so that the first spring 41 is in flange part 21 and the stop of spool 2 with compressive state Between washer 6, the active force that spool 2 is supported towards valve opening position is generated；Second stopper section 62 and second spring 42 are towards valve port 1 One end abut, and second spring 42 is supported towards valve opening position, so that second spring 42 is arranged with compressive state in barrier Between part 5 and stop washer 6, the active force that retaining piece 5 is supported towards valve opening position is generated.

In detail, stop washer 6 can be set to tubular, and using an axial end face as the first stopper section 61, at it The axial other end is equipped with the extension that at least part extends radially outward, as the second stopper section 62.Second stopper section 62 are specifically as follows the retaining ring of ring structure, can be used as the spring base of second spring 42, for being supported to second spring.

At this point, stop washer 6 can be set in outside spool 2, the second stopper section 62 and the fixed company of valve body 7 can also be passed through It connects；Second spring 42 is set in outside the stop washer 6, is abutted against with the second stopper section 62, and the inner hollow chamber of stop washer 6 can With for accommodating spool 2, barrel and the first spring 41 are on same axially-extending line, then the first effect of the first spring 41 End 411 is compressed via the flange part 21 of spool 2, and the barrel end face (i.e. the first stopper section 61) of the other end and the stop washer 6 It abuts.

When the second stopper section 62 is set as annular, stop washer 6 is also provided with the inner ring with second stopper section 62 Hollow cavity connection notch section 63, as in Figure 3-5, so that the circulation mediums such as refrigerant can be via the notch section 63 and valve The entire valve chamber of body 7 is connected, and fills the gap around spool 2, has good trafficability performance.

In conjunction with Fig. 3-5, the valve closing process of normal-open electromagnetic valve of the present invention is described in detail.

As shown in figure 3, electromagnetic part 3 does not apply valve closing active force, the first spring 41 and second to spool 2 under original state Spring 42 is in compressive state, and the first spring 41 supports the flange part 21 of spool 2 by the first effect end 411, so that spool 2 The valve opening working position of valve port 1 is held it away from, second spring 42 supports retaining piece 5 by the second effect end 423, so that retaining piece 5 axially abut with static iron core 32.

As shown in figure 4, electromagnetic part 3 generates electromagnetic force when needing close port 1, driving spool 2 is transported towards valve closing direction It is dynamic, at this point, spool 2 further compresses the first spring 41, when the first spring 41 is by compression predetermined amount, spool by flange part 21 2 flange part 21 moves to the position abutted against with the barrier portion 51 of retaining piece 5, which is that spool 2 acts solely on first The stage of spring 41, the first stage that can be referred to as during valve closing.

As shown in figure 5, with the increase of electromagnetic force, spool 2 continues to move towards valve closing direction, with flange part 21 compress every The barrier portion 51 of stopper, and this is compressed into power and is transferred to second spring 42, so that retaining piece 5 and second spring 42 are towards valve closing side To moving synchronously, valve closing active force occupies leading position, and the elastic force of the first spring 41 and second spring 42 is finally overcome to complete Valve closing.

Direction in valve closing direction, that is, Fig. 2-5 as described herein from top to bottom, that is, the side by the direction valve port 1 of spool 2 To, then, it is in the top in figure in front of valve closing direction, is axially away from the direction of valve port 1 in other words, locates It is in the lower section in figure in the rear in valve closing direction, in other words in the axial direction close to the direction of valve port 1.

As shown in fig. 6, the size with power is vertical if the axial distance using dynamic iron core 31 with respect to static iron core 32 is horizontal axis Axis can then draw the curve of electromagnetic force during valve closing, elasticity when in the prior art using a spring as returning spring 4 The curve of power, the present invention in using 42 this two springs of the first spring 41 and second spring match in the form of as reply bullet The curve of elastic force summation both when spring 4, and then the present invention and the prior art are analyzed.

It will be appreciated from fig. 6 that in the prior art, the section there are an electromagnetic force less than a spring power, in the section, It will basically can not complete the valve closing driving to spool 2；And in the present invention, when the first spring 41 and second spring 42 match, The two acts on stage by stage, so that electromagnetic force is consistently greater than elastic force, and then ensure that the continual and steady progress of valve closing, reduces and closes Valve difficulty improves valve closing reliability.

It was verified that the maximum power pressure difference of normal-open electromagnetic valve only has when using a spring as returning spring 4 2.8Mpa, and the returning spring 4 for using the first spring 41 of the invention and the combination of second spring 42 to be formed, maximum power pressure difference can It is even higher to reach 3.7Mpa.

Normal-open electromagnetic valve of the invention, can be diaphragm electromagnetic valve or piston electromagnetic valve, can also be according to need To be applied in the solenoid valve of various structure types.

It should be noted that the present invention is only illustrated the structures such as spool 2, returning spring 4, no matter which kind of is specifically used The other parts of structure type, normal-open electromagnetic valve are referred to the prior art, and details are not described herein again.

Normal-open electromagnetic valve provided by the present invention is described in detail above.Specific case used herein is to this The principle and embodiment of invention is expounded, and core of the invention that the above embodiments are only used to help understand is thought Think.It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, may be used also With several improvements and modifications are made to the present invention, these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims (11)

1. a kind of normal-open electromagnetic valve, including the spool (2) for opening and closing valve port (1), the spool (2) is connected with driving, and it is closed The electromagnetic part (3) of valve and the returning spring (4) for keeping it in valve opening working position, when energization, the electromagnetic part (3) is inhaled in electromagnetism Power effect is lower to push the spool (2) to close the valve port (1), which is characterized in that the returning spring (4) includes the first spring (41) and stiffness factor be greater than first spring (41) second spring (42)；On valve closing direction, the electromagnetic part (3) is pushed away It moves after first spring (41) compressed predetermined amount by the spool (2), then compresses the second spring (42).

2. normal-open electromagnetic valve as described in claim 1, which is characterized in that first spring (41) and the second spring (42) effect end when valve closing is formed with the one end of respective separate the valve port (1)；On valve closing direction, first spring (41) effect end is in front of the effect end of the second spring (42).

3. normal-open electromagnetic valve as claimed in claim 2, which is characterized in that further include that retaining piece (5) is suppressed described second Between the effect end and the electromagnetic part (3) of spring (42), and have barrier in the barrier portion in the spool (2) valve closing path (51)；When first spring (41) is compressed predetermined amount by the spool (2), the position for compressing the barrier portion (51) is moved to It sets, and then the second spring (42) is compressed by the barrier portion (51).

4. normal-open electromagnetic valve as claimed in claim 3, which is characterized in that the retaining piece (5) is tubular retaining ring, the cylinder The first end of shape retaining ring is abutted with the effect end of the second spring (42), and inwardly prolongs to form protrusion at least part diameter, As the barrier portion (51), the second end of the tubular retaining ring is abutted with the electromagnetic part (3).

5. normal-open electromagnetic valve as claimed in claim 4, which is characterized in that the barrier portion (51) in a ring, described first Spring (41) is set in the spool (2) outside, and the spool (2) has and first bullet far from the one end of the valve port (1) The flange part (21) that spring (41) abuts, the barrier portion (51) accommodate first spring (41) and institute with the hollow cavity of its inner ring It states spool (2), annular entity portion with the flange part (21) for abutting.

6. normal-open electromagnetic valve as claimed in claim 4, which is characterized in that the second spring (42) includes along axial screw Circular spring body (421) and the end (422) for being connected to the spring body (421) one end, described in the end (422) is used as The effect end of second spring (42).

7. normal-open electromagnetic valve as claimed in any one of claims 1 to 6, which is characterized in that further include that there is the first stopper section (61) and the stop washer (6) of the second stopper section (62), first stopper section (61) and first spring (41) are towards institute The one end for stating valve port (1) abuts, the one end of second stopper section (62) and the second spring (42) towards the valve port (1) It abuts.

8. normal-open electromagnetic valve as claimed in claim 7, which is characterized in that the stop washer (6) is cylindrical in shape, and with axial direction An end face form first stopper section (61), at least part of the other end extends radially outward, formed described second Stopper section (62).

9. normal-open electromagnetic valve as claimed in claim 8, which is characterized in that the stop washer (6) is set in the spool (2) outside, it and by second stopper section (62) and valve body (7) is connected, the second spring (42) is set in the stop pad Enclose (6) outside.

10. normal-open electromagnetic valve as claimed in claim 7, which is characterized in that second stopper section (62) is in a ring, described Stop washer (6) is equipped with the notch section (63) being connected to the hollow cavity of the inner ring of second stopper section (62).

11. normal-open electromagnetic valve as claimed in claim 7, which is characterized in that the electromagnetic part (3) includes the dynamic of magnetic attraction Iron core (31) and static iron core (32), and for the dynamic iron core (31) provide magnetic force electromagnetic coil, the dynamic iron core (31) with Spool (2) connection.