CN207880128U - A kind of check valve and liquid chromatograph - Google Patents

Abstract

It includes valve body, valve deck, spool, valve ball and valve pocket, valve body upper end opening, lower end closed and inner hollow that the utility model, which provides a kind of check valve and liquid chromatograph, check valve,；Valve deck is covered at valve body upper end opening, and bonnet central is equipped with the first through hole and the second through-hole of sequential communication；Spool is set to valve inner, and spool is equipped with the third through-hole that be connected to the second through-hole, and the aperture of first through hole and third through-hole, which is less than, states valve ball diameter, and valve ball is in the second through-hole, and valve ball is set on third through-hole；Fourth hole is offered on valve body bottom wall, third through-hole is connected to fourth hole；It is in sealing contact between valve deck and spool and between spool and valve body；Valve pocket is sheathed on valve deck lateral wall and valve body lateral wall.Liquid chromatograph uses above-mentioned check valve.Check valve proof pressure provided by the utility model can reach 90MPa or more, be more widely applied.

Description

A kind of check valve and liquid chromatograph

Technical field

The utility model is related to fluid control device technical field, a kind of check valve is referred in particular to and with the check valve Liquid chromatograph.

Background technology

In the prior art, the check valve of the high pressure pump of conventional liquid chromatograph is mostly applied to system pressure In the infusion pump of 40MPa, as shown in fig. 6, the structure of existing check valve is mostly to be internally provided with spool and ball in valve body Seat group, is sealed between spool and ball seat by flat seal 100, the both ends of valve body are carried out by seal head 200 respectively Sealing.Although this structure has advantage simple in structure, small, it is applied to the high pressure pump of liquid chromatograph When middle, the seal head 200 at valve body both ends does not simultaneously tolerate super-pressure, and after pressure is more than 90MPa, seal head 200 easily fails, and The seal head 200 at valve body both ends can be deformed around when check valve compresses, formed permanent deformation, to influence sealing and Assembly, stability, repeatability and analysis precision during causing liquid chromatograph to carry out sample analysis are adversely affected.

Utility model content

The purpose of this utility model is to provide a kind of check valve and liquid chromatograph, the proof pressure of the check valve and can reach 90MPa or more, use is more extensive, can apply in superelevation liquid chromatographic system；And the liquid chromatograph of the utility model uses The check valve of the utility model can be effectively ensured stability of the liquid chromatograph carry out sample analysis during, repeat Property and analysis precision.

In order to achieve the above object, the utility model provides a kind of check valve, wherein the check valve includes valve body, valve Lid, spool, valve ball and valve pocket, the valve body are the tubular structure of upper end opening, lower end closed and inner hollow；The valve deck is close Capping set on the valve body upper end opening at, at the center of the valve deck be equipped with from top to bottom the first through hole of sequential communication and Second through-hole；The spool is set to the inside of the valve body, and the third being connected to second through-hole is offered on the spool The aperture of through-hole, the aperture of the first through hole and the third through-hole is respectively less than the diameter of the valve ball, and the valve ball is set to In second through-hole, and the valve ball is set on the third through-hole of the spool；It is opened up on the bottom wall of the valve body There are fourth hole, the third through-hole to be connected to the fourth hole；Between the valve deck and the spool and the spool It is in sealing contact between the inner surface of the bottom wall of the valve body；The valve pocket sealing shroud is set to the lateral wall of the valve deck With on the lateral wall of the valve body.

Check valve as described above, wherein the check valve further includes the ball valve of at least one set of one-way conduction from the bottom to top Component, the ball valve assembly is set to the inside of the valve body, and the ball valve assembly is located at the lower section of the spool, and the ball It is that sealing connects between valve module and the spool and between the inner surface of the bottom wall of the ball valve assembly and the valve body It touches.

Check valve as described above, wherein the ball valve assembly includes ball cover, ball seat and sphere, the center of the ball cover Place is equipped with the from top to bottom fifth hole of sequential communication and the 6th through-hole, offers at the center of the ball seat and leads to the described 6th The aperture of 7th through-hole of hole connection, the aperture of the fifth hole and the 7th through-hole is respectively less than the diameter of the sphere, The sphere is set in the 6th through-hole, and the sphere is set on the 7th through-hole of the ball seat, the ball cover Lower face and the upper surface of the ball seat between be equipped with ring packing piece.

Check valve as described above, wherein on the lower face of the valve deck, on the upper surface of the ball cover, the ball cover Lower face on and the valve body bottom wall inner surface on be recessed with seal groove, the section of the seal groove is in semicircle Shape or V-type.

Check valve as described above, wherein the junction between the first through hole and second through-hole forms first Annular step surface is equipped with the first bar, lower surface and the first annular step of first bar in the first through hole Face is concordant or the lower surface of first bar extends to the lower section in the first annular step face；

Junction between the fifth hole and the 6th through-hole forms the second annular step surface, the fifth hole In be equipped with the second bar, the lower surface of second bar is concordant with second annular step surface or second bar Lower surface extends to the lower section of second annular step surface.

Check valve as described above, wherein between the lower face of the valve deck and the upper surface of the spool, the spool Lower face and the ball valve assembly between and the inner surface of the bottom wall of the ball valve assembly and the valve body between be all provided with There is ring packing piece.

Check valve as described above, wherein the upper surface of the valve deck is concavely provided with upper sealing ring slot；The bottom of the valve body The outer surface of wall is concavely provided with lower sealing ring slot, and ring packing is equipped in the upper sealing ring slot and the lower sealing ring slot Circle.

Check valve as described above, wherein the outer diameter of the upper end of the valve body is less than the outer diameter of the lower end of the valve body, institute The third annular step surface being formed on the lateral wall of valve body upward is stated, the outer diameter of the upper end of the valve deck is more than the valve deck The outer diameter of lower end is formed with fourth annular step surface directed downwardly, the outer diameter of the upper end of the valve deck on the lateral wall of the valve deck It is identical as the outer diameter of the upper end of the valve body, in the state that the valve bonnet seal is covered on the upper end opening of the valve body, institute It states fourth annular step surface to be bonded with the upper surface of the valve body, is located at the upper of the valve deck above the upper surface of the valve body The lateral wall at end is concordant with the lateral wall of the upper end of the valve body, and the valve pocket sealing shroud is set to the outside of the upper end of the valve body On wall and on the lateral wall of the upper end of the valve deck, and the lower face of the valve pocket is sealed against in the third annular step surface On.

Check valve as described above, wherein the valve body is valve body made of stainless steel, and the valve deck is made of stainless steel Valve deck.

The utility model additionally provides a kind of liquid chromatograph, wherein the liquid chromatograph includes as described above single To valve.

Compared with prior art, as follows the advantages of the utility model：

The lower end of valve body has been set as closed and has been opened up on the lower face of valve body by check valve provided by the utility model Fourth hole, and using valve deck come the upper end opening of closed valve, meanwhile, in the outer of the upper end of the lateral wall and valve body of valve deck Side wall upper sleeve gasket has set valve pocket and has been sealed come the gap between valve body and valve deck, need not be arranged at the both ends of valve body close End socket, be pressurized when, valve body, valve deck and valve pocket be not in be pressurized it is larger and generate around permanent deformation even fail and The case where influencing sealing, the sealing performance of the check valve of the utility model is effectively ensured, while can be by the unidirectional of the utility model The proof pressure of valve is improved to 90MPa or more, and check valve provided by the utility model is made to be more widely applied.

Liquid chromatograph provided by the utility model uses check valve provided by the utility model, so as to effectively protect Demonstrate,prove stability, repeatability and analysis precision of the liquid chromatograph of the utility model during carrying out sample analysis.

Description of the drawings

The following drawings is only intended in doing schematic illustration and explanation to the utility model, does not limit the model of the utility model It encloses.Wherein：

Fig. 1 is the cross-sectional view of check valve provided by the utility model；

Fig. 2 is the perspective exploded view of check valve provided by the utility model；

Fig. 3 is the structural schematic diagram of the valve body of check valve provided by the utility model；

Fig. 4 is the structural schematic diagram of the valve deck of check valve provided by the utility model；

Fig. 5 is the structural schematic diagram of the ball cover of the ball valve assembly of check valve provided by the utility model；

Fig. 6 is the cross-sectional view of check valve in the prior art.

Drawing reference numeral explanation：

The utility model：

1, valve body；

11, fourth hole；

12, third annular step surface；

13, lower sealing ring slot；

14, lower ring convex portion；

2, valve deck；

21, first through hole；

22, the second through-hole；

23, first annular step face；

24, the first bar；

25, fourth annular step surface；

26, upper sealing ring slot；

27, upper ring convex portion；

3, spool；

31, third through-hole；

4, valve ball；

5, valve pocket；

6, ball valve assembly；

61, ball cover；

611, fifth hole；

612, the 6th through-hole；

613, the second annular step surface；

614, the second bar；

62, ball seat；

621, the 7th through-hole；

63, sphere；

7, ring packing piece；

8, ring type seal；

9, seal groove；

The prior art：

100, flat seal；

200, seal head

Specific implementation mode

In order to have clearer understanding to the technical solution of the utility model, purpose and effect, originally in conjunction with description of the drawings The specific implementation mode of utility model.

As shown in fig. 1~fig. 5, the utility model provides a kind of check valve, wherein check valve include valve body 1, valve deck 2, Spool 3, valve ball 4 and valve pocket 5, valve body 1 are the tubular structure of upper end opening, lower end closed and inner hollow, i.e., valve body 1 is inside Hollow tubular structure, and the upper end of valve body 1 is in open shape, the lower end of valve body 1 is in closed；2 sealing cover of valve deck is set to valve body 1 Upper end opening at, the from top to bottom first through hole 21 of sequential communication and the second through-hole 22 are equipped at the center of valve deck 2, first is logical Hole 21 and the second through-hole 22 can be regarded as a step through-hole；Spool 3 is set to the inside of valve body 1, i.e. spool 3 is set to valve deck Between 2 lower face and the inner surface of the bottom wall of valve body 1), the third through-hole being connected to the second through-hole 22 is offered on spool 3 31, the aperture of first through hole 21 is respectively less than the diameter of valve ball 4 with the aperture of third through-hole 31, that is to say, that can be by first through hole 21 and second through-hole 22 regard a step through-hole that upper inner diameter is smaller and lower inner diameter is larger as, valve ball 4 is set to described the In two through-holes 22, and valve ball 4 is set on the third through-hole 31 of spool 3, due to aperture and the third through-hole 31 of first through hole 21 Aperture be respectively less than the diameter of valve ball 4, therefore valve ball 4 can be effectively maintained to the inside of the second through-hole 22, prevent valve ball 4 from One through-hole 21 or third through-hole 31 are moved to the outside of the second through-hole 22, and fourth hole 11, third are offered on the bottom wall of valve body 1 Through-hole 31 is connected to by ball valve assembly 6 with fourth hole 11, i.e. first through hole 21, the second through-hole 22, third through-hole 31 and the 4th From top to bottom sequential communication, first through hole 21, the second through-hole 22, third through-hole 31 and fourth hole 11 are to set with one heart to through-hole 11 It sets, when fluid flows in the check valve of the utility model, is the inside for flowing into valve body 1 from fourth hole 11, then sequentially wears Cross ball valve assembly 6, third through-hole 31, the second through-hole 22 and the outside that check valve is flowed out to from first through hole 21；Using process In, no fluid by when, valve ball 4 set on the third through-hole 31 of spool 3, have fluid by when, fluid moves from the bottom to top, Valve ball 4 is jacked up by upward active force, makes to generate gap between valve ball 4 and spool 3, and fluid is flowed into from the gap Second through-hole 22 simultaneously continues upward through the outside that first through hole 21 flows out to check valve, and when fluid has refluence trend (i.e. The trend flowed from top to bottom) when, valve ball 4 is by downward active force, to closely set on third through-hole 31, Make fluid that can not be flowed into third through-hole 31 from the second through-hole 22.

It is in sealing contact between valve deck 2 and spool 3 and between the inner surface of the bottom wall of spool 3 and valve body 1, to protect Demonstrate,proving fluid will not be along the bottom wall in gap and spool 3 and valve body 1 between valve deck 2 and spool 3 in check valve flow process Inner surface between gap leakage；5 sealing shroud of valve pocket is set on the lateral wall of valve deck 2 and the lateral wall of valve body 1, valve pocket 5 For by the clearance seal between valve deck 2 and valve body 1, to prevent gap of the fluid between valve deck 2 and valve body 1 from revealing.

Preferably, setting reset element can be connected on valve ball 4, reset element can be provided at 4 top of valve ball One end of push spring, push spring is connect with the top of valve ball 4, and the other end can be connected to shape between first through hole 21 and the second through-hole 22 At step surface on (i.e. hereafter described in first annular step face 23)；Or reset element can also be provided in valve ball 4 One end of the tension spring of lower section, tension spring is connect with the bottom of valve ball 4, and the other end of tension spring is fixed on the inner wall of third through-hole 31； Again or reset element can also be the spring being arranged radially in the second through-hole 22, the both ends of spring respectively with the second through-hole 22 inner wall connection can apply a downward active force so that logical in no fluid by the way that reset element is arranged to valve ball 4 In the case of crossing, the holding of valve ball 4 is made to set on third through-hole 31.

Further, as shown in fig. 1~fig. 5, the utility model provides a kind of check valve, wherein check valve further includes The ball valve assembly 6 of at least one set of one-way conduction from the bottom to top, ball valve assembly 6 is set to the inside of valve body 1, and ball valve assembly 6 is located at The lower section of spool 3, i.e. spool 3 are from top to bottom ranked sequentially the inside for being set to valve body 1 with ball valve assembly 6, wherein work as ball valve group When part 6 is equipped with multigroup, multigroup ball valve assembly 6 is from top to bottom ranked sequentially (only to be said by taking one group of ball valve assembly 6 as an example in Fig. 1 It is bright), and be that sealing connects between ball valve assembly 6 and spool 3 and between the inner surface of the bottom wall of ball valve assembly 6 and valve body 1 It touches, to prevent the gap between gap and ball valve assembly 6 and valve body 1 of the fluid between spool 3 and ball valve assembly 6 from revealing.

Further as shown in Figure 1, Figure 2 and shown in Fig. 5, the utility model provides a kind of check valve, wherein ball valve assembly 6 The fifth hole 611 of sequential communication from top to bottom and the are equipped with including ball cover 61, ball seat 62 and sphere 63, at the center of ball cover 61 Six through-holes 612, fifth hole 611 is similar with the structure of the second through-hole 22 with the structure of the 6th through-hole 612 with first through hole 21, the Five through-holes 611 and the 6th through-hole 612 can also regard a step through-hole as, be offered at the center of ball seat 62 respectively with the 4th Through-hole 11, the connection of the 6th through-hole 612 the 7th through-hole 621, fifth hole 611, the 6th through-hole 612 and the 7th through-hole 621 and the One through-hole 21, the second through-hole 22, third through-hole 31 and fourth hole 11 are to be arranged concentrically, and first through hole 21, the second through-hole 22, third through-hole 31, fifth hole 611, the 6th through-hole 612, the 7th through-hole 621 and fourth hole 11 from top to bottom sequentially connect Logical, the aperture of the aperture of fifth hole 611 and the 7th through-hole 621 is respectively less than the diameter of sphere 63, it is to be appreciated that the 5th is logical The step through-hole that hole 611 and the 6th through-hole 612 are formed also is a step through-hole that upper inner diameter is smaller and lower inner diameter is larger, Sphere 63 is set in the 6th through-hole 612, and sphere 63 is set on the 7th through-hole 621 of ball seat 62, due to fifth hole 611 Aperture and the aperture of the 7th through-hole 621 are respectively less than the diameter of sphere 63, therefore can sphere 63 be effectively maintained at the 6th through-hole 612 Inside, prevent sphere 63 to be moved to the outside of the 6th through-hole 612 from fifth hole 611 or the 7th through-hole 621, it can be seen that The structure of structure substantially similar valve deck 2 and spool 3 between ball cover 61 and ball seat 62；Similarly, in use, no fluid By when, sphere 63 set on the 7th through-hole 621 of ball seat 62, have fluid by when, fluid moves from the bottom to top, sphere 63 It is jacked up by upward active force, makes to generate gap between sphere 63 and ball seat 62, fluid flows into the from the gap Five through-holes 611 simultaneously continue upwardly into third through-hole 31, and (what is flowed from top to bottom becomes when fluid has refluence trend Gesture) when, sphere 63 is by downward active force, to closely set on the 7th through-hole 621, making the fluid can not be from the Six through-holes 612 flow into the 7th through-hole 621, and ring packing piece 7 is equipped between the lower face and the upper surface of ball seat 62 of ball cover 61, Ring packing piece 7 is sealed for gap between the lower face of ball cover 61 and the upper surface of ball seat 62, prevent fluid from It is revealed between the lower face of ball cover 61 and the upper surface of ball seat 62.Can be the unidirectional of the utility model by the way that ball valve assembly 6 is arranged Valve provides multi-ensuring, and when generating abrasion between valve ball 4 and spool 3 and flowing backwards, ball valve assembly 6 can prevent refluence Occur, avoids the leakage of fluid.

Preferably, as shown in figure 3, the utility model provides a kind of check valve, wherein first through hole 21 and second is logical Junction between hole 22 forms first annular step face 23, and the first bar 24 is equipped in first through hole 21, the first bar 24 Lower surface is concordant with first annular step face 23 or the lower surface of the first bar 24 extends to the lower section in first annular step face 23； Wherein, the first bar 24 can be and the first bar 24 along the lower part for being radially disposed at first through hole 21 of first through hole 21 Both ends are connected to the lower part of the inner wall of first through hole 21, it should be noted that should ensure that the lower surface of the first bar 24 with First annular step face 23 is concordant or is less than first annular step face 23；Or first bar 24 can be axially disposed at The inside of one through-hole 21 makes the both ends point of radial strut specifically, radial strut first is arranged in the inside of first through hole 21 It does not connect with the inner wall of first through hole 21, then the upper end of the first bar 24 is connected on supporting rod, make the first bar 24 Lower end extends to concordant with first annular step face 23 or stretches in the second through-hole 22, wherein the first bar 24 can be and valve It can also be to be welded on valve deck 2 that lid 2, which is integrally formed processing or the first bar 24,；It can be in valve by the way that the first bar 24 is arranged It when ball 4 is by larger upward ejection force, prevents valve ball 4 from blocking first through hole 21, makes the following of valve ball 4 and first through hole 21 Always gap is remained between edge, so that fluid passes through；

Shown in Fig. 4, the junction between fifth hole 611 and the 6th through-hole 612 forms the second annular table Terrace 613 is equipped with the second bar 614 in fifth hole 611, and the lower surface of the second bar 614 and the second annular step surface 613 are flat Together or the lower surface of the second bar 614 extends to the lower section of the second annular step surface 613, wherein the second bar 614 is logical the 5th Set-up mode in hole 611 is identical as set-up mode of first bar 24 in first through hole 21, is not repeating herein；Equally Ground can prevent sphere 63 from blocking the 5th logical by the way that the second bar 614 is arranged when sphere 63 is by larger upward ejection force Hole 611 makes to remain with gap always between sphere 63 and the lower edge of fifth hole 611, so that fluid passes through.

Preferably, as shown in Figures 1 and 2, the utility model provides a kind of check valve, wherein the lower face of valve deck 2 Between the upper surface of spool 3, between the lower face of spool 3 and the upper surface of the ball valve assembly 6 and lower face of ball valve assembly 6 Ring packing piece 7 is equipped between the inner surface of the bottom wall of valve body 1, when ball valve assembly 6 be equipped with it is multigroup when, each two is adjacent Ball valve assembly 6 between also be provided with ring packing piece 7.The lower end of valve deck 2 can be further improved by the way that ring packing piece 7 is arranged Between face and the upper surface of spool 3, between the lower face of spool 3 and the upper surface of the ball valve assembly 6 and lower end of ball valve assembly 6 Sealing performance between the inner surface of the bottom wall of face and valve body 1 further decreases the probability of fluid leakage, improves the utility model Check valve resistance to pressure.

Preferably, the utility model provides a kind of check valve, wherein ring packing piece 7 has good mechanical property Can, fatigue durability is good, and abrasion resistence is high, and excellent heat resistance, shrinking percentage, linear expansion coefficient are small, good stability of the dimension, can effectively keep away Exempt from due to the case where being generated larger radial deformation by Fluid pressure.

Further, as shown in Fig. 1, Fig. 3~Fig. 5, the utility model provides a kind of check valve, wherein valve deck 2 It is recessed on lower face, on the upper surface of ball cover 61, on the lower face of ball cover 61 and on the inner surface of the bottom wall of valve body 1 Seal groove 9, the section semicircular in shape or V-type of seal groove 9.

By the way that seal groove 9 is arranged, when the upper surface of the lower face of valve deck 2 and spool 3 compresses, ring packing piece 7 can be to The direction for stretching to seal groove 9 occurs a small amount of deformation and is contacted with the fitting of the inner wall of seal groove 9, increases ring packing piece 7 and valve Contact area between the lower face of lid 2, to further increase the sealing performance between valve deck 2 and spool 3；Similarly, exist Recessed seal groove 9 on the upper surface of ball cover 61, the lower face of ball cover 61 and on the inner surface of the bottom wall of valve body 1, equally Can improve between the upper surface of ball cover 61 and the lower face of spool 3, between the lower face of ball cover 61 and the upper surface of ball seat 62 with And the sealing performance between the inner surface of the bottom wall of the lower face and valve body 1 of ball seat 62.

Preferably, as shown in Fig. 1, Fig. 3 and Fig. 4, the utility model provides a kind of check valve, wherein valve deck 2 it is upper End face is concavely provided with upper sealing ring slot 26；The outer surface of the bottom wall of valve body 1 is concavely provided with lower sealing ring slot 13, upper sealing ring slot 26 be equipped with ring type seal 8 in lower sealing ring slot 13, ring type seal 8 is used for by check valve provided by the utility model It is sealed between other assemblies when in the high pressure pump of liquid chromatograph, prevents fluid leakage.Wherein, upper close The formation of seal ring slot 26 can also regard the upper ring convex portion 27 for being formed and being arranged concentrically on the upper surface of valve deck 2, two upper rings as Form upper sealing ring slot 26 between protrusion 27, and the longitudinal cross-sections in two upper ring convex portions 27 are size reduction from the bottom to top Taper, when in sealing contact between valve deck 2 and other assemblies, forming face seals between ring type seal 8 and other assemblies, on two Ring convex portion 27 forms two lines sealing between other assemblies respectively, to constitute compound sealing structure；Similarly, lower sealing Annular groove 13 can also regard two lower ring convex portions 14 on the outer surface for the bottom wall for being formed in valve body 1 as and be enclosed, with It is also the same to constitute the compound sealing structure being made of face sealing and linear sealing when other assemblies assemble, to effectively improve this Sealing performance between the check valve and other assemblies of utility model.

Ring type seal 8 has superior dimensionally stable characteristic, can meet under the relatively high operating mode of dimension precision requirement Requirement.

Further, as shown in Figure 1, the utility model provides a kind of check valve, wherein the outer diameter of the upper end of valve body 1 Less than the outer diameter of the lower end of valve body 1, third annular step surface 12 upward, the upper end of valve deck 2 are formed on the lateral wall of valve body 1 Outer diameter be more than valve deck 2 lower end outer diameter, be formed with fourth annular step surface 25 directed downwardly, valve deck 2 on the lateral wall of valve deck 2 Upper end outer diameter it is identical as the outer diameter of the upper end of valve body 1,2 sealing cover of valve deck be set to valve body 1 upper end opening in the state of, Fourth annular step surface 25 is bonded with the upper surface of valve body 1, is located at the outside of the upper end of the valve deck 2 above the upper surface of valve body 1 Wall is concordant with the lateral wall of the upper end of valve body 1, and 5 sealing shroud of valve pocket is set on the lateral wall of the upper end of valve body 1 and the upper end of valve deck 2 Lateral wall on, and the lower face of valve pocket 5 is sealed against in third annular step surface 12.

Preferably, the utility model provides a kind of check valve, wherein valve body 1 is valve body 1 made of stainless steel, valve Lid 2 is valve deck 2 made of stainless steel.

The utility model additionally provides a kind of liquid chromatograph, wherein liquid chromatograph includes check valve as described above. Specifically, replacing check valve used in the high pressure pump in liquid chromatograph using check valve provided by the utility model. It should be noted that the other structures component of liquid chromatograph is identical as the structure member of existing liquid chromatograph, herein not It repeats again, difference lies in the liquid chromatograies of the utility model with existing liquid chromatograph for the liquid chromatograph of the utility model The check valve used in the high pressure pump of instrument is check valve provided by the utility model.

Compared with prior art, as follows the advantages of the utility model：

The lower end of valve body has been set as closed and has been opened up on the lower face of valve body by check valve provided by the utility model Fourth hole, and using valve deck come the upper end opening of closed valve, meanwhile, in the outer of the upper end of the lateral wall and valve body of valve deck Side wall upper sleeve gasket has set valve pocket and has been sealed come the gap between valve body and valve deck, need not be arranged at the both ends of valve body close End socket, be pressurized when, valve body, valve deck and valve pocket be not in be pressurized it is larger and generate around permanent deformation even fail and The case where influencing sealing, the sealing performance of the check valve of the utility model is effectively ensured, while can be by the unidirectional of the utility model The proof pressure of valve improves 90MPa or more, even up to 110MPa or more, makes check valve application provided by the utility model more Extensively.

Liquid chromatograph provided by the utility model uses check valve provided by the utility model, so as to effectively protect Demonstrate,prove stability, repeatability and analysis precision of the liquid chromatograph of the utility model during carrying out sample analysis.

The above descriptions are merely exemplary embodiments of the present utility model, is not limited to the model of the utility model It encloses.Any those skilled in the art, it is made etc. under the premise of not departing from the design and principle of the utility model With variation and modification, the range of the utility model protection should all be belonged to.

Claims (10)

1. a kind of check valve, which is characterized in that the check valve includes valve body, valve deck, spool, valve ball and valve pocket, the valve body For the tubular structure of upper end opening, lower end closed and inner hollow；The valve bonnet seal is covered on the upper end opening of the valve body Locate, the from top to bottom first through hole of sequential communication and the second through-hole are equipped at the center of the valve deck；The spool is set to described The inside of valve body, offers the third through-hole being connected to second through-hole on the spool, the aperture of the first through hole with The aperture of the third through-hole is respectively less than the diameter of the valve ball, and the valve ball is set in second through-hole, and the valve ball It sets on the third through-hole of the spool；Offer fourth hole on the bottom wall of the valve body, the third through-hole with The fourth hole connection；Between the valve deck and the spool and the inner surface of the bottom wall of the spool and the valve body Between be in sealing contact；The valve pocket sealing shroud is set on the lateral wall of the valve deck and the lateral wall of the valve body.

2. check valve according to claim 1, which is characterized in that the check valve further includes at least one set of single from the bottom to top To the ball valve assembly of conducting, the ball valve assembly is set to the inside of the valve body, and the ball valve assembly is located at the spool Lower section, and between the ball valve assembly and the spool and the inner surface of the bottom wall of the ball valve assembly and the valve body it Between be in sealing contact.

3. check valve according to claim 2, which is characterized in that the ball valve assembly includes ball cover, ball seat and sphere, institute It states and is equipped with the from top to bottom fifth hole of sequential communication and the 6th through-hole at the center of ball cover, offered at the center of the ball seat The aperture of the 7th through-hole being connected to the 6th through-hole, the aperture of the fifth hole and the 7th through-hole is respectively less than described The diameter of sphere, the sphere is set in the 6th through-hole, and the sphere sets the 7th through-hole in the ball seat On, ring packing piece is equipped between the lower face of the ball cover and the upper surface of the ball seat.

4. check valve according to claim 3, which is characterized in that on the lower face of the valve deck, the upper end of the ball cover Seal groove, the sealing are recessed on face, on the lower face of the ball cover and on the inner surface of the bottom wall of the valve body The section semicircular in shape or V-type of slot.

5. check valve according to claim 3 or 4, which is characterized in that between the first through hole and second through-hole Junction form first annular step face, be equipped with the first bar in the first through hole, the lower surface of first bar with The first annular step face is concordant or the lower surface of first bar extends to the lower section in the first annular step face；

Junction between the fifth hole and the 6th through-hole forms the second annular step surface, is set in the fifth hole There is the second bar, the lower surface of second bar is concordant with second annular step surface or the following table of second bar Face extends to the lower section of second annular step surface.

6. according to claim 2~4 any one of them check valve, which is characterized in that the lower face of the valve deck and the valve Between the upper surface of core, between the lower face of the spool and the ball valve assembly and the ball valve assembly and the valve body Ring packing piece is equipped between the inner surface of bottom wall.

7. according to Claims 1 to 4 any one of them check valve, which is characterized in that the upper surface of the valve deck is concavely provided with Upper sealing ring slot；The outer surface of the bottom wall of the valve body is concavely provided with lower sealing ring slot, the upper sealing ring slot with it is described under Ring type seal is equipped in closure gasket groove.

8. according to Claims 1 to 4 any one of them check valve, which is characterized in that the outer diameter of the upper end of the valve body is less than The outer diameter of the lower end of the valve body is formed with third annular step surface upward on the lateral wall of the valve body, the valve deck The outer diameter of upper end is more than the outer diameter of the lower end of the valve deck, and fourth annular step directed downwardly is formed on the lateral wall of the valve deck Face, the outer diameter of the upper end of the valve deck is identical as the outer diameter of the upper end of the valve body, and the valve is covered in the valve bonnet seal In the state of the upper end opening of body, the fourth annular step surface is bonded with the upper surface of the valve body, is located at the valve body The lateral wall of the upper end of the valve deck above upper surface is concordant with the lateral wall of the upper end of the valve body, the valve pocket sealing shroud On the lateral wall of the upper end of the valve body and on the lateral wall of the upper end of the valve deck, and the lower face sealing of the valve pocket It is resisted against in the third annular step surface.

9. according to Claims 1 to 4 any one of them check valve, which is characterized in that the valve body is valve made of stainless steel Body, the valve deck are valve deck made of stainless steel.

10. a kind of liquid chromatograph, which is characterized in that the liquid chromatograph includes such as claim 1~9 any one of them Check valve.