Proportional flow valve

Abstract

A proportional flow valve (100), comprising a valve shell assembly (1), an electromagnet assembly (2), a valve core assembly, a sealing ring structure, and a pre-tightening force structure. The valve shell assembly (1) forms an annular mounting cavity (a); an air inlet seat (6) is formed on the open end of the annular mounting cavity (a); an air inlet channel (61) that upwardly and downwardly extends is formed in the air inlet seat (6); the electromagnet assembly (2) is used for providing an upward magnetic attraction force; the valve core assembly has an upward moving stroke under the driving of the magnetic attraction force; an air guide channel (b) is formed in the valve core assembly; the inlet of the air guide channel (b) is formed at the lower end of the valve core assembly, and is communicated with the air inlet channel (61); an outlet is formed at the side end of the valve core assembly; the sealing ring structure comprises a sealing ring (41) having an inner ring sleeved on the valve core assembly and an outer ring fixed in the annular mounting cavity (a); and the pre-tightening force structure is provided between the valve core assembly and the inner wall of the annular mounting cavity (a) so as to provide a downward pre-tightening force for the valve core assembly.

Description

TECHNICAL FIELDThe application relates to the technical field of gas flow control and valves, inparticular to a proportional flow valve.BACKGROUNDIn the proportional flow valve, the flow output value has a linear relationshipwith the valve core opening, and the valve core opening has a linearrelationship with the input electrical signal through the intermediate conversionmechanism, thus determining the linear relationship between the flow outputvalue and the input signal.Normally, regular solenoid valves adopt the structure of electromagnetic coiland linear spring, which is usually used as an on-off valve, that is, theelectromagnetic coil overcomes the spring force to open the valve core afterbeing energized. The electromagnetic force generated by the electromagneticcoil has an exponential relationship with the air gap, while the linear spring hasa linear relationship with the compression or extension amount, in the case ofsame displacement, the added value of the electromagnetic force is greater thanthat of the linear spring, therefore the opening of the valve core can be directlyopened to the maximum. However, it is difficult to meet the requirement thatthe proportional flow valve is stable in a certain position during the opening ofthe valve port, hence the linear relationship between the flow output value andinput signal cannot be realized, and the proportional adjustment of the flowcannot be realized.In some working conditions, such as transfer ventilator, the venturi nozzle isusually used to introduce air after the proportional valve, but the gas passingthrough the proportional valve would generate a large back pressure whenpassing through the venturi nozzle, which leads to the regular proportionalvalve not working normally under the working condition of high back pressureand he nce unable to realize the proportional adjustment of the flow.So far, there is no proper proportional flow valve in the market that can solvethe above problems. Therefore, it is necessary to design a new proportionalflow valve which can not only solve the influence of high back pressure, butalso work stably.TECHNICAL SOLUTIONSThe main purpose of this application is to provide a proportional flow valve,which aims to solve the influence of high back pressure and allow theproportional flow valve work stably.In order to achieve the above purpose, the proportional flow valve provided bythe present application includes:a valve housing assembly, formed with a mounting cavity with an opening atlower end, an air inlet seat is formed at an opening end of the mounting cavityand located at the middle part of the mounting cavity, and an air inlet passageextending up and down is formed in the air inlet seat;an electromagnet assembly, arranged at an upper end of the mounting cavityand used for providing upward magnetic attraction;a valve core assembly, arranged in the mounting cavity and located at themiddle part of the mounting cavity, an annular mounting cavity is formedbetween the valve core assembly and an inner wall surface of the mountingcavity; driven by the magnetic attraction, the valve core assembly has anupward moving stroke; an air-guide passage is formed in the valve coreassembly, an inlet of the air-guide passage is formed at a lower end of the valvecore assembly and is communicated with the air inlet passage, and an outlet isformed at side end of the valve core assembly;a sealing ring structure, including a sealing ring sealed in the annular mountingcavity, an inner ring of the sealing ring is sleeved on the valve core assembly,and an outer ring of the sealing ring is fixedly installed in the mounting cavity,so as to separate the annual mounting cavity into a closed upper annualmounting cavity and a closed lower annular mounting cavity, and the upperannual mounting cavity is communicated with the outlet of the air-guidepassage;a preload force structure, arranged between the valve core assembly and aninner wall of the mounting cavity, and used for providing downward preloadforce for the valve core assembly; andan air outlet gap communicating with the lower annular mounting cavity can beformed between the lower end of the valve core assembly and an upper end ofthe air inlet seat.In an embodiment, the preload force structure includes an annular elastic sheet,an inner end of the annular elastic sheet is fixed to the valve core assembly, andan outer end is fixed to the inner wall of the mounting cavity; an annularsurface of the annular elastic sheet is provided with a hollow patterncombination, the hollow pattern combination is a central symmetric structureand includes a plurality of hollow pattern units, and the number of the hollowpattern units is an integer multiple of natural number 2 or more; and / orthe electromagnet assembly includes a coil extending up and down and fixedlyinstalled in the mounting cavity and a static armature fixedly installed in aninner hole of the coil, when the coil is electrified, the static armature forms themagnetic attraction; the valve core assembly includes a mobile armature and avalve core, the mobile armature is sandwiched between the static armature andthe valve core, an upper end of the mobile armature is spaced from a lower endof the static armature, so as to form an electromagnet air gap; a lower end ofthe mobile armature is connected with an upper end of the valve core, and theair outlet air gap is formed between a lower end face of the valve core and anupper end face of the air inlet seat.In an embodiment, a first air-guide passage segment is through installed at thelower end face of the valve core, and an lower end face of the mobile armatureis provided with a first mounting hole extending up and down; a sidewallsurface of the first mounting hole is provided with a second air-guide passagesegment, the upper end of the valve core is installed in the first mounting hole,and the first air-guide passage segment is communicated with the secondair-guide passage segment to jointly form the air-guide passage; and / orthe mobile armature is positioned at a lower end of the inner hole of the coil,and a non-metallic magnetic separator is arranged between the upper end of themobile armature and the lower end of the static armature; and / orthe mobile armature is at least partially positioned in the coil and has amounting segment positioned in the coil;the proportional flow valve further includes a first magnetic shield sleeveextending up and down, and the first magnetic shield sleeve is arrangedbetween the coil and the mobile armature and at least partially covers themounting segment.In an embodiment, an upper end of the first magnetic shield sleeve ispositioned in the inner hole of the coil, and a lower end of the first magneticshield sleeve protrudes from a lower end of the coil;the lower end of the static armature and the upper end of the mobile armatureare both installed in the first magnetic shield sleeve, and the sidewall of thestatic armature is in sealing abutment with an inner wall of the first magneticshield sleeve.In an embodiment, the air-guide passage is formed in the valve core and themobile armature;an air gap is formed between a sidewall of the mobile armature and an outersidewall of the first magnetic shield sleeve, and the air gap communicates withthe electromagnet air gap, the outlet of the air-guide passage and the upperannular mounting cavity.In an embodiment, the mounting cavity is arranged in steps to form a firstannular step surface arranged downwards;the proportional flow valve further includes a first annular support seat locatedbelow the first annular step surface, and the outer ring of the first annularsupport seat is in sealing abutment with an inner sidewall of the mountingcavity, the inner ring of the first annual support seat is sleeved on the valvecore assembly, and a first annular mounting space is formed between an upperend face of the first annual support seat and the first annular step surface, andthe sealing ring is clamped in the annular space.In an embodiment, an inner hole of the first annular support seat is set as atapered hole with a small top and a large bottom;the lower end of the valve core assembly extends from a lower end of thetapered hole and movably abuts against the upper end face of the air inlet seat,and the lower end of the valve core assembly is arranged in steps to form asecond annular step surface arranged upwards;the preload force structure includes an annual elastic sheet, an inner ring of theannual elastic sheet abuts against the second annular step surface, and an outerring of the annual elastic sheet is fixed on a lower end face of the first annularsupport seat, and the second annular step surface is located above the lower endface of the first annular support seat.In an embodiment, the valve housing assembly includes:a housing, a lower end face of the housing is penetrated with a mounting holeextending up and down, and the coil is mounted in the mounting hole;a second annual support seat, installed at the lower end of the housing, and aninner hole of the second annual support seat is communicated with themounting hole to jointly form the mounting cavity;a valve body, installed in the inner hole of the second annular support seat andlocated above the air inlet seat;the valve body and the air inlet seat are integrally arranged.In an embodiment, an upper end sidewall of the valve body is in threadedconnection with an inner wall of the inner hole of the second annular supportseat; and / orthe second annular support seat includes a support seat cylinder and a secondmagnetic shield sleeve extending upward from an upper end face of the supportseat cylinder, the upper end face of the support seat cylinder is in sealingabutment with the lower end face of the housing, an upper end of the secondmagnetic shield sleeve extends into the inner hole of the coil, the lower end ofthe static armature and the upper end of the mobile armature are both installedin the second magnetic shield sleeve, and the side wall of the static armature isin sealing abutment with an inner wall of the second magnetic shield sleeve;and / oran upper end face of the valve body is penetrated with a second mounting hole,and the second mounting hole is arranged in steps to form an abutment stepsurface arranged upward, and the proportional flow valve further includes afirst clamping assembly, the first clamping assembly is annularly arranged andlocated on the abutment step surface; an outer ring of the first clampingassembly is in sealing abutment with an inner wall surface of the secondmounting hole; a first annular clamping space is formed in the first clampingassembly; the inner ring of the sealing ring is hermetically sleeved on the valvecore assembly, and the outer ring of the sealing ring is clamped in the firstannular clamping space.In an embodiment, the proportional flow valve further includes a transitionblock, the transition block is positioned in the mounting hole and below thecoil, and the transition block is hermetically sleeved at a lower end of thesecond magnetic shield sleeve, a side wall of the transition block is in sealingabutment with a side wall of the mounting hole, and a lower end face of thetransition block is mounted to the upper end face of the support seat cylinder;and / oran inner hole of the support seat cylinder is set as a tapered hole with a smalltop and a large bottom, and the lower end of the valve core assembly isarranged in steps to form a third annular step surface arranged upwards, and thepreload force structure includes an annular elastic sheet, the inner ring of theannual elastic sheet abuts against the third annular step surface, and the outerring of the annual elastic sheet is fixed on the upper end face of the valve body.In an embodiment, the lower end face of the valve core is provided with aconnecting hole;the lower end face of the mobile armature is provided with a third mountinghole extending up and down;the valve core assembly further includes a connecting column, an upper end ofthe connecting column is installed in the third mounting hole, a lower end ofthe connecting column is inserted into the connecting hole, and the air-guidepassage is formed in the connecting column.In an embodiment, the connecting column is arranged in steps to form a fourthstep surface arranged upwards, and a second annular mounting space is formedbetween the fourth step surface and the lower end face of the mobile armature;the mounting cavity is formed with a fifth step surface arranged downwards,and the fifth step surface is located below the fourth step surface;the preload force structure includes an annular elastic sheet, the inner ring ofthe annular elastic sheet is clamped in the second annular mounting space, andthe outer ring of the annular elastic sheet abuts against the fifth step surface.In an embodiment, the connecting column is also formed with a sixth stepsurface arranged downwards, and a third annular mounting space is formedbetween the sixth step surface and an upper end face of the valve core;the mounting cavity is formed with a seventh annular step surface arrangeddownwards, and the seventh annular step surface is provided with a secondclamping assembly, the second clamping assembly is annularly arranged, anouter ring of the second clamping assembly is in sealing abutment with theinner wall surface of the mounting cavity, and a fourth annular clamping spaceis formed in the second clamping assembly;the inner ring of the sealing ring is clamped in the third annular mounting space,and the outer ring of the sealing ring is clamped in the fourth annular clampingspace.According the technical solution provided by the application, the air inletpassage is communicated with the air-guide passage, hence the gas at the airinlet of the air inlet passage is introduced into the closed upper annularmounting cavity, the sealing ring generates a downward pressure on the valvecore assembly. And the preload force structure provides a downward preloadforce on the valve core assembly, when the proportional solenoid valve doesnot work, the pressure and preload force form a downward resultant force, sothat the lower end of the valve core assembly is in sealing abutment with theupper end of the air inlet seat to avoid air leakage of the proportional solenoidvalve; when the proportional solenoid valve works, the valve core assembly issubjected to an upward electromagnetic force provided by the electromagnetassembly, and the air pressure of the air inlet provides an upward thrust forcefor the valve core assembly; when there is no back pressure in the air outlet gap,the four forces of pressure, preload force, electromagnetic force and thrustforce are balanced with each other, so that the valve core assembly can bestabilized at the working position; when there is back pressure in the air outletgap, the back pressure provides an upward back pressure for the valve core, inthis case, the five forces of pressure, preload force, electromagnetic force,thrust force and back pressure are balanced, so that the valve core can still bestable in the working position, therefore the proportional valve can work stablyunder different working conditions, the impact of high back pressure on theproportional flow valve is eliminated, and the effect is good.BRIEF DESCRIPTION OF THE DRAWINGSIn order to illustrate the technical solutions in the embodiments of the presentapplication or in the prior art more clearly, the drawings in the description ofthe embodiments of the present application will be briefly introduced below. Itis obvious that the drawings in the following description only show someembodiments of the present application. A person of ordinary skill in the artcan obtain other drawings according to the structures shown in these drawingswithout any creative effort.Fig. 1 is a structural schematic diagram of a first embodiment of a proportionalflow valve in accordance with the present application;Fig. 2 is a structural schematic diagram of a second embodiment of aproportional flow valve in accordance with the present application;Fig. 3 is a structural schematic diagram of a third embodiment of a proportionalflow valve in accordance with the present application;Fig. 4 is a structural diagram of an embodiment of the annular elastic sheetshown in Fig. 1;Fig. 5 is a structural diagram of another embodiment of the annular elasticsheet shown in Fig. 1;Fig. 6 is a curve diagram showing the relationship between electromagneticforce and electromagnet air gap of the proportional flow valve in accordancewith the present application;Fig. 7 is a curve diagram showing the relationship between preload force andvalve core opening of the proportional flow valve in accordance with thepresent application;Fig. 8 is a curve diagram showing the relationship between each force anddisplacement of the valve core of the proportional flow valve in accordancewith the present application.Reference signs in the drawings are as follows.TableFeatures, functions, objects and advantages of the present application will befurther illustrated with reference to the drawings and embodiments.DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTSIn the following, the technical solutions in the embodiments of the applicationwill be clearly and completely described with reference to the drawings. It isapparent that the described embodiments are some but not all of theembodiments of the present application. All other embodiments obtained by aperson of ordinary skill in the art without any creative effort on the basis of theembodiments in the present application shall fall into the scope of the presentapplication.It should be noted that the directional indications (such as up, down, left, right,front, back, etc.) in the embodiments of this application are only used toillustrate the relative position relationship among components and theirmovement in a certain point of view (as shown in the drawings), and if thepoint of view changes, the directional indications would also changeaccordingly.In addition, terms such as "first" and "second" in the embodiments of thisapplication are only used for descriptive purposes, and cannot be considered asindicating or implying their relative priorities or implicitly indicating thenumber of indicated technical features. Therefore, the features defined as"first" and "second" can explicitly or implicitly include at least one of theindicated features. In addition, the meaning of "and / or" in the descriptionincludes three alternative solutions. For example, "A and / or B" includesSolution A, Solution B, or Solution A and Solution B. Furthermore, thetechnical solutions of each embodiment may be combined with each other, onthe premise that it can be achieved by those skilled in the art. When thecombination of technical solutions is contradictory or impossible, it shall beconsidered that this combination of technical solutions does not exist and doesnot fall into the protection scope of the present application.In the proportional flow valve, the flow output value has a linear relationshipwith the valve core opening, and the valve core opening has a linearrelationship with the input electrical signal through the intermediate conversionmechanism, thus determining the linear relationship between the flow outputvalue and the input signal.Normally, regular solenoid valves adopt the structure of electromagnetic coiland linear spring, which is usually used as an on-off valve, that is, theelectromagnetic coil overcomes the spring force to open the valve core afterbeing energized. The electromagnetic force generated by the electromagneticcoil has an exponential relationship with the air gap, while the linear spring hasa linear relationship with the compression or extension amount, in the case ofsame displacement, the added value of the electromagnetic force is greater thanthat of the linear spring, therefore the opening of the valve core can be directlyopened to the maximum. However, it is difficult to meet the requirement thatthe proportional flow valve is stable in a certain position during the opening ofthe valve port, hence the linear relationship between the flow output value andinput signal cannot be realized, and the proportional adjustment of the flowcannot be realized.In some working conditions, such as transfer ventilator, the venturi nozzle isusually used to introduce air after the proportional valve, but the gas passingthrough the proportional valve would generate a large back pressure whenpassing through the venturi nozzle, which leads to the regular proportionalvalve not working normally under the working condition of high back pressureand hence unable to realize the proportional adjustment of the flow.So far, there is no proper proportional flow valve in the market that can solvethe above problems. Therefore, it is necessary to design a new proportionalflow valve which can not only solve the influence of high back pressure, butalso work stably.The application provides a proportional flow valve, wherein Figs. 1 to 5 arestructural schematic diagrams of the proportional flow valve of embodimentsin accordance with the application.Referring to Figs. 1 to 3, the proportional flow valve 100 includes a valvehousing assembly 1, an electromagnet assembly 2, a valve core assembly, asealing ring 41 structure and a preload force structure. The valve housingassembly 1 is formed with a mounting cavity with an opening at lower end, anair inlet seat 6 is formed at an opening end of the mounting cavity and locatedat the middle part of the mounting cavity, and an air inlet passage 61extending up and down is formed in the air inlet seat 6 ; the electromagnetassembly 2 is arranged at an upper end of the mounting cavity and used forproviding upward magnetic attraction; the valve core assembly is arranged inthe mounting cavity and located at the middle part of the mounting cavity, anannular mounting cavity a is formed between the valve core assembly and aninner wall surface of the mounting cavity; driven by the magnetic attraction,the valve core assembly has an upward moving stroke; an air-guide passage bis formed in the valve core assembly, an inlet of the air-guide passage b isformed at a lower end of the valve core assembly and is communicated withthe air inlet passage 61 , and an outlet is formed at side end of the valve coreassembly; the sealing ring structure includes a sealing ring 41 sealed in theannular mounting cavity a , an inner ring of the sealing ring 41 is sleeved onthe valve core assembly, and an outer ring of the sealing ring 41 is fixedlyinstalled in the mounting cavity, so as to separate the annual mounting cavityinto a closed upper annual mounting cavity a1 and a closed lower annularmounting cavity a2, and the upper annual mounting cavity a1 is communicatedwith the outlet of the air-guide passage b; the preload force structure isarranged between the valve core assembly and an inner wall of the mountingcavity, and used for providing downward preload force for the valve coreassembly; and an air outlet gap communicating with the lower annularmounting cavity a2 can be formed between the lower end of the valve coreassembly and an upper end of the air inlet seat 6.According the technical solution provided by the application, the air inletpassage 61 is communicated with the air-guide passage b, hence the gas at theair inlet of the air inlet passage 61 is introduced into the closed upper annularmounting cavity 41, the sealing ring 41 generates a downward pressure on thevalve core assembly. And the preload force structure provides a downwardpreload force on the valve core assembly, when the proportional solenoid valvedoes not work, the pressure and preload force form a downward resultant force,so that the lower end of the valve core assembly is in sealing abutment with theupper end of the air inlet seat 6 to avoid air leakage of the proportionalsolenoid valve; when the proportional solenoid valve works, the valve coreassembly is subjected to an upward electromagnetic force provided by theelectromagnet assembly 2, and the air pressure of the air inlet provides anupward thrust force for the valve core assembly; when there is no backpressure in the air outlet gap, the four forces of pressure, preload force,electromagnetic force and thrust force are balanced with each other, so that thevalve core assembly can be stabilized at the working position; when there isback pressure in the air outlet gap, the back pressure provides an upward backpressure for the valve core, in this case, the five forces of pressure, preloadforce, electromagnetic force, thrust force and back pressure are balanced, sothat the valve core can still be stable in the working position, therefore theproportional valve can work stably under different working conditions, theimpact of high back pressure on the proportional flow valve 100 is eliminated,and the effect is good.It should be noted that the air inlet seat 6 is provided with an air outlet passage62 extending up and down, when the valve core assembly moves up, the lowerend of the valve core assembly and the upper end of the air inlet seat 6 form theair outlet gap, which communicates with the air inlet passage 61 and the airoutlet passage 62 to realize air outlet.In order to enable the preload force structure provide preload force for thevalve core assembly and realize proportional flow control, the electromagneticforce curve is determined on the electromagnetic force curve according to theopening ratio of the outlet air gap and the current change ratio. Theelectromagnetic force curve is nonlinear, so it is necessary to match thevariation law of the preload force curve with the electromagnetic force curve toachieve an a pproximate linear relationship. Therefore, referring to Figs. 5 and 6,the preload force structure includes an annular elastic sheet 51, the inner end ofannular elastic sheet 51 is fixed to the valve core assembly, and the outer end isfixed to the inner wall of the mounting cavity, so that the annular elastic sheet51 would be prone to deform, thus facilitating the provision of preload forcefor the valve core assembly. The annular surface of the annular elastic sheet 51is provided with a hollow pattern combination, the hollow pattern combinationis a central symmetrical structure and includes a plurality of hollow patternunits, the number of the hollow pattern combination is an integer multiple of anatural number of 2 or more, so that the preload force structure can providepreload force for the valve core assembly, and the relationship curve betweenpreload force and displacement is consistent with the electromagnetic forcecurve, thus facilitating the realization of proportional flow control.The electromagnet assembly 2 includes a coil 21 extending up and down andfixedly installed in the mounting cavity and a static armature 22 fixedlyinstalled in an inner hole of the coil 21, when the coil 21 is electrified, the staticarmature 22 forms the magnetic attraction; the valve core assembly includes amobile armature 31 and a valve core 32, the mobile armature 31 is sandwichedbetween the static armature 22 and the valve core 33, an upper end of themobile armature 31 is spaced from a lower end of the static armature 22, so asto form an electromagnet air gap c; a lower end of the mobile armature 31 isconnected with an upper end of the valve core 32, and the air outlet air gap isformed between a lower end face of the valve core 32 and an upper end face ofthe air inlet seat 6. In this way, because the lower end of the mobile art 31 isconnected with the upper end of the valve core 32, the motion states of themobile art 31 and the valve core 32 are consistent, when the coil 21 isenergized, the static armature 22 forms magnetic attraction, by changing thesize of the electromagnet air gap c, the magnetic attraction is changed, and thechange amount of the electromagnet air gap c is also the moving distance of thevalve core 32, and the magnetic attraction attracts the mobile armature 31 tomove upwards, thereby driving the valve core 32 to move upwards, so that theoutlet air gap is formed between the lower end face of the valve core 32 and theupper end face of the air inlet seat 6, hence the gas entering from the air inletpassage 61 can be discharged through the outlet air gap.Specifically, the air-guide passage b is formed on the valve core 32 and mobilearmature 31, so that the structure is simple and easy to manufacture.In an embodiment, a first air-guide passage segment is through installed at thelower end face of the valve core 32, and an lower end face of the mobilearmature 31 is provided with a first mounting hole 311 extending up and down;a sidewall surface of the first mounting hole 311 is provided with a secondair-guide passage segment b2, the upper end of the valve core 32 is installed inthe first mounting hole 311, and the first air-guide passage segment b1 iscommunicated with the second air-guide passage segment b2 to jointly formthe air-guide passage b. With this arrangement, the outside air enters the firstair-guide passage segment b1 and the second air-guide passage segment b2from the air inlet passage 61 in turn, and finally converges in the closed upperannular mounting cavity a1. And the converged gas causes the sealing ring 41to generate a downward pressure on the valve core 32, so that the lower end ofthe valve core 32 is in sealing abutment with the upper end of the air inlet seat6, and the proportional flow valve 100 is prevented from leaking.It should be noted that the air-guide passage b is formed on the valve core 32,so that the structure is simple and easy to manufacture.Referring to Fig. 3, the mobile armature 31 is positioned at a lower end of theinner hole of the coil 21, and a non-metallic magnetic separator 7 is arrangedbetween the upper end of the mobile armature 31 and the lower end of thestatic armature 22. This arrangement plays a buffering role and prevents themobile armature 31 from colliding with the static armature 22 to be damagedunder the action of electromagnetic force.Referring to fig. 1 and fig. 2, the mobile armature 31 is at least partiallypositioned in the coil 21 and has a mounting segment positioned in the coil 21;the proportional flow valve 100 further includes a first magnetic shield sleeve 8extending up and down, and the first magnetic shield sleeve 8 is arrangedbetween the coil 21 and the mobile armature 31 and at least partially covers themounting segment. In this way, the first magnetic shield sleeve 8 covers themounting segment, so as to prevent the mobile armature 31 from generatingelectromagnetic force after the coil 21 is electrified, thereby avoiding affectingthe sensitivity of the mobile armature 31 under the electromagnetic force of thestatic armature 22.It should be noted that there are many types of materials can be used to achievethe magnetic isolation effect, such as silicon steel, stainless steel and copper. Inthe present application, the first magnetic shield sleeve 8 is made of copper.In an embodiment, an upper end of the first magnetic shield sleeve 8 ispositioned in the inner hole of the coil 21, and a lower end of the first magneticshield sleeve 8 protrudes from a lower end of the coil 21;the lower end of the static armature 22 and the upper end of the mobilearmature 31 are both installed in the first magnetic shield sleeve 8, and thesidewall of the static armature 22 is in sealing abutment with an inner wall ofthe first magnetic shield sleeve 8. This arrangement prevents the staticarmature 22 and the first magnetic shield sleeve 8 from leaking air, therebyavoiding affecting the air tightness of the proportional flow valve 100.Referring to Figs. 1 and 2, the air-guide passage b is formed in the valve core32 and the mobile armature 31; an air gap is formed between a sidewall of themobile armature 31 and an outer sidewall of the first magnetic shield sleeve 8,and because the air gap communicates with the electromagnet air gap c, theoutlet of the air-guide passage b and the upper annular mounting cavity a1, theoutside air can be converged in the closed upper annual mounting cavity a1after passing through the electromagnet air gap c, the air-guide passage b andthe air gap from the air inlet passage 61. The converged gas causes the sealingring 41 to generate a downward pressure on the valve core 32, so that the lowerend of the valve core 32 is in sealing abutment with the upper end of the airinlet seat 6, and the proportional flow valve 100 is prevented from leaking.Referring to Fig. 1, the mounting cavity is arranged in steps to form a firstannular step surface 11 arranged downwards; the proportional flow valve 100further includes a first annular support seat 9 located below the first annularstep surface 11, and the outer ring of the first annular support seat 9 is insealing abutment with an inner sidewall of the mounting cavity, the inner ringof the first annual support seat 9 is sleeved on the valve core assembly, and afirst annular mounting space is formed between an upper end face of the firstannual support seat 9 and the first annular step surface 11, and the sealing ring41 is clamped in the annular space. With this arrangement, the installation ofthe sealing ring 41 is realized.In an embodiment, an inner hole of the first annular support seat 9 is set as atapered hole with a small top and a large bottom; the lower end of the valvecore assembly extends from a lower end of the tapered hole and movably abutsagainst the upper end face of the air inlet seat 6, and the lower end of the valvecore assembly is arranged in steps to form a second annular step surface 33arranged upwards; the preload force structure includes an annual elastic sheet51, an inner ring of the annual elastic sheet 51 abuts against the second annularstep surface 33, and an outer ring of the annual elastic sheet 51 is fixed on alower end face of the first annular support seat 9, and because the secondannular step surface 33 is located above the lower end face of the first annularsupport seat 9, the annual elastic sheet 51 generates a downward preload forceon the valve core assembly, which has a good effect. And the tapered hole isarranged with a small top and a large bottom, thus providing an activity spacefor the annual elastic sheet 51.Referring to Fig. 2, the valve housing assembly 1 includes a housing 12, asecond annular support seat 13 and a valve body 14. A lower end face of thehousing 12 is penetrated with a mounting hole extending up and down, and thecoil 21 is mounted in the mounting hole; the second annual support seat isinstalled at the lower end of the housing 12, and an inner hole of the secondannual support seat 13 is communicated with the mounting hole to jointly formthe mounting cavity; the valve body is installed in the inner hole of the secondannular support seat 13 and located above the air inlet seat 6; the valve body 14and the air inlet seat 6 are integrally arranged, so as to facilitate precisemachining.Specifically, an upper end sidewall of the valve body 14 is in threadedconnection with an inner wall of the inner hole of the second annular supportseat 13. With this arrangement, the valve body 14 and the second annularsupport seat 13 are hermetically connected, and the disassembly and assemblyare convenient.Referring to Fig. 2, the second annular support seat 13 includes a support seatcylinder 131 and a second magnetic shield sleeve 132 extending upward froman upper end face of the support seat cylinder 131, the upper end face of thesupport seat cylinder 131 is in sealing abutment with the lower end face of thehousing 12, an upper end of the second magnetic shield sleeve 132 extends intothe inner hole of the coil 21, the lower end of the static armature 22 and theupper end of the mobile armature 31 are both installed in the second magneticshield sleeve 132, and the side wall of the static armature 22 is in sealingabutment with an inner wall of the second magnetic shield sleeve 132. In thisway, the upper end of the mobile armature 31 is covered by the secondmagnetic shield sleeve 132, so as to prevent the mobile armature 31 fromgenerating electromagnetic force after the coil 21 is energized, therebyavoiding affecting the sensitivity of the mobile armature 31 under theelectromagnetic force of the static armature 22.In order to install the sealing ring 41, referring to Fig. 2, an upper end face ofthe valve body 14 is penetrated with a second mounting hole, and the secondmounting hole is arranged in steps to form an abutment step surface 141arranged upward, and the proportional flow valve 100 further includes a firstclamping assembly 10, the first clamping assembly 10 is annularly arrangedand located on the abutment step surface 141; an outer ring of the firstclamping assembly 10 is in sealing abutment with an inner wall surface of thesecond mounting hole; a first annular clamping space is formed in the firstclamping assembly 10; the inner ring of the sealing ring 41 is hermeticallysleeved on the valve core assembly, and the outer ring of the sealing ring 41 isclamped in the first annular clamping space. With this arrangement, theinstallation of the sealing ring 41 is realized.In order to assure the installation of the second annular support seat 13 morestable, the proportional flow valve 100 further includes a transition block 101,the transition block 101 is positioned in the mounting hole and below the coil21 for supporting the coil 21, and the transition block 101 is hermeticallysleeved at a lower end of the second magnetic shield sleeve 132, a side wall ofthe transition block 101 is in sealing abutment with a side wall of the mountinghole, and a lower end face of the transition block 101 is mounted to the upperend face of the support seat cylinder 131. In this way, the transition block 101is connected with the support seat cylinder 131, so that the second annularsupport seat 13 can be installed more stably.Referring to Fig. 2, an inner hole of the support seat cylinder 131 is set as atapered hole with a small top and a large bottom, and the lower end of thevalve core assembly is arranged in steps to form a third annular step surface 34arranged upwards, and the preload force structure includes an annular elasticsheet 51, the inner ring of the annual elastic sheet 51 abuts against the thirdannular step surface 34, and the outer ring of the annual elastic sheet 51 is fixedon the upper end face of the valve body 14. In this way, the annual elastic sheet51 generates downward preload force on the valve core assembly, which has agood effect. And the tapered hole is arranged with a small top and a largebottom, thus providing an activity space for the annual elastic sheet 51.In order to prevent the transition block 101 from rotating relative to the supportseat cylinder 131, an anti-rotation structure is further arranged between thelower end face of the transition block 101 and the upper end face of the supportseat cylinder 131. In this way, the transition block 101 is prevented fromrotating relative to the support seat cylinder 131, so that the air tightness of theproportional flow valve 100 is ensured and the effect is good.It should be noted that the anti-rotation structure may be a convex and a groovewhich cooperate with each other. In the present application, the anti-rotationstructure is a pin, through which the anti-rotation positioning of the transitionblock 101 and the support seat cylinder 131 is realized, and the transition block101 is prevented from rotating relative to the support seat cylinder 131.Referring to Fig. 3, the lower end face of the valve core 32 is provided with aconnecting hole; the lower end face of the mobile armature 31 is provided witha third mounting hole extending up and down;the valve core assembly further includes a connecting column 35, an upper endof the connecting column 35 is installed in the third mounting hole, a lower endof the connecting column 35 is inserted into the connecting hole, and theair-guide passage b is formed in the connecting column 35. In this way, thevalve core 32 and mobile armature 31 are connected through the connectingcolumn 35, and the air-guide passage b is arranged at the connecting column 35,which has a simple structure and is easy to manufacture.In an embodiment, the connecting column 35 is arranged in steps to form afourth step surface 351 arranged upwards, and a second annular mountingspace is formed between the fourth step surface 351 and the lower end face ofthe mobile armature 31; the mounting cavity is formed with a fifth step surface15 arranged downwards, and the fifth step surface 15 is located below thefourth step surface 351; the preload force structure includes an annular elasticsheet 51, the inner ring of the annular elastic sheet 351 is clamped in thesecond annular mounting space, and the outer ring of the annular elastic sheet51 abuts against the fifth step surface 15. With this arrangement, theinstallation of the annual elastic sheet 51 is realized, and the annual elasticsheet 51 exerts a preload force on the valve core 32 at the initial position, sothat the sealing effect of the proportional flow valve 100 is good.It should be noted that the inner ring of the annual elastic sheet 51 is clampedin the second annular mounting space, and the inner ring of the annual elasticsheet 51 can move up and down in the second annular mounting space.Specifically, referring to Fig. 3, the inner ring of the annual elastic sheet 51abuts on the fourth step surface 351, which facilitates the activity of the annualelastic sheet 51 and has a good effect.In an embodiment, the connecting column 35 is also formed with a sixth stepsurface 352 arranged downwards, and a third annular mounting space is formedbetween the sixth step surface 352 and an upper end face of the valve core 32;the mounting cavity is formed with a seventh annular step surface 16 arrangeddownwards, and the seventh annular step surface 16 is provided with a secondclamping assembly 102, the second clamping assembly 102 is annularlyarranged, an outer ring of the second clamping assembly 102 is in sealingabutment with the inner wall surface of the mounting cavity, and a fourthannular clamping space is formed in the second clamping assembly 102; theinner ring of the sealing ring 41 is clamped in the third annular mounting space,and the outer ring of the sealing ring 41 is clamped in the fourth annularclamping space. With this arrangement, the installation of the sealing ring 41 isrealized with good effect.It should be noted that in the present application, the air gap refers to the valvecore opening of the proportional flow valve, and the gap formed by the gapbetween the lower end of the static armature and the end of the mobilearmature is an electromagnet air gap. By changing the electromagnet air gap,the electromagnetic force is changed. And the air gap variation is also the valvecore variation. Referring to Figs. 6 to 8, the electromagnetic force is inverselyquadratic proportional to the air gap variation (equal to the valve opening), andthe preload force is also inversely quadratic proportional to the valve opening,the variation law of the electromagnetic force curve and the preload force curveis the same, and the distance between the electromagnetic force curve and thepreload force curve is always the same, so that the force for realizing the valvecore balance together with the electromagnetic force and preload force is aconstant value. And by adjusting the distance between the electromagneticforce curve and preload force curve, the proportional flow valve of theapplication may be applied to the working conditions with and without backpressure, and the effect is good.The above are only preferred embodiments of the present application and arenot intended to limit the present application. Any equivalent structuraltransformation made by using the contents of the specification and drawings ofthis application under the concept of this application, or direct / indirectapplication in other related technical fields are included in the patent protectionscope of this application.

Claims

1. A proportional flow valve, comprising: a valve housing assembly, formed with a mounting cavity with an opening at lower end, an air inlet seat is formed at an opening end of the mounting cavity and located at the middle part of the mounting cavity, and an air inlet passage extending up and down is formed in the air inlet seat; an electromagnet assembly, arranged at an upper end of the mounting cavity and used for providing upward magnetic attraction; a valve core assembly, arranged in the mounting cavity and located at the middle part of the mounting cavity, an annular mounting cavity is formed between the valve core assembly and an inner wall surface of the mounting cavity; driven by the magnetic attraction, the valve core assembly has an upward moving stroke; an air-guide passage is formed in the valve core assembly, an inlet of the air-guide passage is formed at a lower end of the valve core assembly and is communicated with the air inlet passage, and an outlet is formed at side end of the valve core assembly; a sealing ring structure, comprising a sealing ring sealed in the annular mounting cavity, an inner ring of the sealing ring is sleeved on the valve core assembly, and an outer ring of the sealing ring is fixedly installed in the mounting cavity, so as to separate the annual mounting cavity into a closed upper annual mounting cavity and a closed lower annular mounting cavity, and the upper annual mounting cavity is communicated with the outlet of the air-guide passage; a preload force structure, arranged between the valve core assembly and an inner wall of the mounting cavity, and used for providing downward preload force for the valve core assembly; and an air outlet gap communicating with the lower annular mounting cavity can be formed between the lower end of the valve core assembly and an upper end of the air inlet seat.

2. The proportional flow valve of claim 1, wherein the preload force structure comprises an annular elastic sheet, an inner end of the annular elastic sheet is fixed to the valve core assembly, and an outer end is fixed to the inner wall of the mounting cavity; an annular surface of the annular elastic sheet is provided with a hollow pattern combination, the hollow pattern combination is a central symmetric structure and comprises a plurality of hollow pattern units, and the number of the hollow pattern units is an integer multiple of natural number 2 or more; and / or the electromagnet assembly comprises a coil extending up and down and fixedly installed in the mounting cavity and a static armature fixedly installed in an inner hole of the coil, when the coil is electrified, the static armature forms the magnetic attraction; the valve core assembly comprises a mobile armature and a valve core, the mobile armature is sandwiched between the static armature and the valve core, an upper end of the mobile armature is spaced from a lower end of the static armature, so as to form an electromagnet air gap; a lower end of the mobile armature is connected with an upper end of the valve core, and the air outlet air gap is formed between a lower end face of the valve core and an upper end face of the air inlet seat.

3. The proportional flow valve of claim 2, wherein a first air-guide passage segment is through installed at the lower end face of the valve core, and an lower end face of the mobile armature is provided with a first mounting hole extending up and down; a sidewall surface of the first mounting hole is provided with a second air-guide passage segment, the upper end of the valve core is installed in the first mounting hole, and the first air-guide passage segment is communicated with the second air-guide passage segment to jointly form the air-guide passage; and / or the mobile armature is positioned at a lower end of the inner hole of the coil, and a non-metallic magnetic separator is arranged between the upper end of the mobile armature and the lower end of the static armature; and / or the mobile armature is at least partially positioned in the coil and has a mounting segment positioned in the coil; the proportional flow valve further comprises a first magnetic shield sleeve extending up and down, and the first magnetic shield sleeve is arranged between the coil and the mobile armature and at least partially covers the mounting segment.

4. The proportional flow valve of claim 3, wherein an upper end of the first magnetic shield sleeve is positioned in the inner hole of the coil, and a lower end of the first magnetic shield sleeve protrudes from a lower end of the coil; the lower end of the static armature and the upper end of the mobile armature are both installed in the first magnetic shield sleeve, and the sidewall of the static armature is in sealing abutment with an inner wall of the first magnetic shield sleeve.

5. The proportional flow valve of claim 4, wherein the air-guide passage is formed in the valve core and the mobile armature; an air gap is formed between a sidewall of the mobile armature and an outer sidewall of the first magnetic shield sleeve, and the air gap communicates with the electromagnet air gap, the outlet of the air-guide passage and the upper annular mounting cavity.

6. The proportional flow valve of claim 1, wherein the mounting cavity is arranged in steps to form a first annular step surface arranged downwards; the proportional flow valve further comprises a first annular support seat located below the first annular step surface, and the outer ring of the first annular support seat is in sealing abutment with an inner sidewall of the mounting cavity, the inner ring of the first annual support seat is sleeved on the valve core assembly, and a first annular mounting space is formed between an upper end face of the first annual support seat and the first annular step surface, and the sealing ring is clamped in the annular space.

7. The proportional flow valve of claim 6, wherein an inner hole of the first annular support seat is set as a tapered hole with a small top and a large bottom; the lower end of the valve core assembly extends from a lower end of the tapered hole and movably abuts against the upper end face of the air inlet seat, and the lower end of the valve core assembly is arranged in steps to form a second annular step surface arranged upwards; the preload force structure comprises an annual elastic sheet, an inner ring of the annual elastic sheet abuts against the second annular step surface, and an outer ring of the annual elastic sheet is fixed on a lower end face of the first annular support seat, and the second annular step surface is located above the lower end face of the first annular support seat.

8. The proportional flow valve of claim 2, wherein the valve housing assembly comprises: a housing, a lower end face of the housing is penetrated with a mounting hole extending up and down, and the coil is mounted in the mounting hole; a second annual support seat, installed at the lower end of the housing, and an inner hole of the second annual support seat is communicated with the mounting hole to jointly form the mounting cavity; a valve body, installed in the inner hole of the second annular support seat and located above the air inlet seat; the valve body and the air inlet seat are integrally arranged.

9. The proportional flow valve of claim 8, wherein an upper end sidewall of the valve body is in threaded connection with an inner wall of the inner hole of the second annular support seat; and / or the second annular support seat comprises a support seat cylinder and a second magnetic shield sleeve extending upward from an upper end face of the support seat cylinder, the upper end face of the support seat cylinder is in sealing abutment with the lower end face of the housing, an upper end of the second magnetic shield sleeve extends into the inner hole of the coil, the lower end of the static armature and the upper end of the mobile armature are both installed in the second magnetic shield sleeve, and the side wall of the static armature is in sealing abutment with an inner wall of the second magnetic shield sleeve; and / or an upper end face of the valve body is penetrated with a second mounting hole, and the second mounting hole is arranged in steps to form an abutment step surface arranged upward, and the proportional flow valve further comprises a first clamping assembly, the first clamping assembly is annularly arranged and located on the abutment step surface; an outer ring of the first clamping assembly is in sealing abutment with an inner wall surface of the second mounting hole; a first annular clamping space is formed in the first clamping assembly; the inner ring of the sealing ring is hermetically sleeved on the valve core assembly, and the outer ring of the sealing ring is clamped in the first annular clamping space.

10. The proportional flow valve of claim 9, wherein the proportional flow valve further comprises a transition block, the transition block is positioned in the mounting hole and below the coil, and the transition block is hermetically sleeved at a lower end of the second magnetic shield sleeve, a side wall of the transition block is in sealing abutment with a side wall of the mounting hole, and a lower end face of the transition block is mounted to the upper end face of the support seat cylinder; and / or an inner hole of the support seat cylinder is set as a tapered hole with a small top and a large bottom, and the lower end of the valve core assembly is arranged in steps to form a third annular step surface arranged upwards, and the preload force structure comprises an annular elastic sheet, the inner ring of the annual elastic sheet abuts against the third annular step surface, and the outer ring of the annual elastic sheet is fixed on the upper end face of the valve body.

11. The proportional flow valve of claim 2, wherein the lower end face of the valve core is provided with a connecting hole; the lower end face of the mobile armature is provided with a third mounting hole extending up and down; the valve core assembly further comprises a connecting column, an upper end of the connecting column is installed in the third mounting hole, a lower end of the connecting column is inserted into the connecting hole, and the air-guide passage is formed in the connecting column.

12. The proportional flow valve of claim 11, wherein the connecting column is arranged in steps to form a fourth step surface arranged upwards, and a second annular mounting space is formed between the fourth step surface and the lower end face of the mobile armature; the mounting cavity is formed with a fifth step surface arranged downwards, and the fifth step surface is located below the fourth step surface; the preload force structure comprises an annular elastic sheet, the inner ring of the annular elastic sheet is clamped in the second annular mounting space, and the outer ring of the annular elastic sheet abuts against the fifth step surface.

13. The proportional flow valve of claim 12, wherein the connecting column is also formed with a sixth step surface arranged downwards, and a third annular mounting space is formed between the sixth step surface and an upper end face of the valve core; the mounting cavity is formed with a seventh annular step surface arranged downwards, and the seventh annular step surface is provided with a second clamping assembly, the second clamping assembly is annularly arranged, an outer ring of the second clamping assembly is in sealing abutment with the inner wall surface of the mounting cavity, and a fourth annular clamping space is formed in the second clamping assembly; the inner ring of the sealing ring is clamped in the third annular mounting space, and the outer ring of the sealing ring is clamped in the fourth annular clamping space.