CN220505838U - High-precision flow control proportional electromagnetic valve - Google Patents

Abstract

The utility model discloses a high-precision flow control proportional electromagnetic valve, and belongs to the technical field of flow control and valves. Comprises a valve core component, an electromagnet component and a valve body component; the valve core assembly comprises a movable armature; the other end of the movable armature attraction surface is connected with an air guide connecting rod which is axially provided with an air guide through hole, and the air guide connecting rod is connected with a sealing gasket assembly; the air guide connecting rod is provided with a circumferential bulge, and the matching surface of the circumferential bulge and the movable armature is provided with a leaf spring sleeved on the air guide connecting rod; the valve seat is axially provided with an air outlet channel; an air inlet channel is axially arranged on the plugging port; the gas passes through the gas guide through hole, passes through the sealing gasket assembly and is communicated with the gas inlet channel on the sealing opening, so that a gas pressure compensation structure is formed, one part of generated gas pressure acts on the valve core assembly, the other part acts on the valve seat, and the component force of the gas pressure acting on the valve core assembly is used as compensation force for enhancing the sealing effect of the valve core assembly.

Description

High-precision flow control proportional electromagnetic valve

Technical Field

The utility model belongs to the technical field of flow control and valves, and relates to a high-precision flow control proportional electromagnetic valve.

Background

The proportional electromagnetic valve is a special control electromagnetic valve, and the control principle is that the electromagnetic force is generated by inputting an electric signal to drive the valve core and control the opening degree of the valve by means of a special magnetic loop structure, so that stepless adjustment of physical quantities such as flow rate, pressure and the like of flowing media is realized. The position feedback technology is adopted, the position of the valve can be accurately adjusted according to the flow control signal, so that the accurate control requirement is met, therefore, the proportional electromagnetic valve is a common mechanical device in the field of gas flow control, and can be used for medical appliances such as respirators and anesthesia machines, and the use environment of the equipment requires the proportional electromagnetic valve to have the characteristics of high control precision, low power consumption, long service life, high pressure resistance and the like. However, the current common proportional solenoid valve in the field only relies on spring deformation to generate sealing force to realize sealing, which results in the problems of high power consumption, short service life, poor high pressure resistance and the like of the proportional solenoid valve.

Disclosure of Invention

The utility model aims to solve the technical problems that the power consumption, the service life and the high pressure resistance of a proportional electromagnetic valve in the prior art are required to be further optimized, and provides a high-precision flow control proportional electromagnetic valve.

In order to achieve the above purpose, the utility model is realized by adopting the following technical scheme:

in a first aspect, the present utility model provides a high-precision flow control proportional solenoid valve, comprising a valve core assembly, an electromagnet assembly, and a valve body assembly; the valve body assembly comprises a valve seat and a plugging port; the electromagnet assembly and the valve body assembly are connected in a matched mode to form an electromagnetic valve cavity, and the valve core assembly is arranged in the electromagnetic valve cavity; the valve core assembly comprises a movable armature; the other end of the movable armature attraction surface is connected with an air guide connecting rod which is axially provided with an air guide through hole, and the air guide connecting rod is connected with a sealing gasket assembly; the air guide connecting rod is provided with a circumferential bulge, and the matching surface of the circumferential bulge and the movable armature is provided with a leaf spring sleeved on the air guide connecting rod; the valve seat is axially provided with an air outlet channel; an air inlet channel is axially arranged on the plugging port; when the sealing gasket component is attached to the end face of the plugging port, the electromagnetic valve is cut off;

the electromagnet assembly comprises a lower yoke and an upper yoke which are connected in a matched manner, and an electromagnetic coil is arranged in the middle of the lower yoke; the electromagnetic coil is used for providing electromagnetic force for driving the valve core assembly to approach after being electrified, and the electromagnetic valve is connected; the rubber diaphragm sleeved on the air guide connecting rod is arranged on the matching surface of the upper yoke iron and the valve seat.

The utility model is further improved in that:

the inner ring of the rubber diaphragm is pressed by the circumferential bulge and the sealing gasket assembly, and the outer ring of the rubber diaphragm is pressed by the valve seat and the upper yoke.

The valve seat is provided with a valve seat first step surface, and the valve seat first step surface is provided with a diaphragm bottom ring; the upper yoke is sequentially provided with an upper yoke second step surface and an upper yoke first step surface along the direction of fluid entering the electromagnetic valve; a diaphragm top ring is arranged on the second step surface of the upper yoke; the rubber diaphragm is pressed by the diaphragm bottom ring and the diaphragm top ring.

The difference between the inner diameter and the outer diameter of the diaphragm bottom ring is smaller than the difference between the inner diameter and the outer diameter of the diaphragm top ring.

The contact surface of the sealing gasket assembly and the inner ring of the rubber diaphragm is provided with a first step surface of the sealing gasket assembly; the contact surface of the valve seat and the outer ring of the rubber diaphragm is provided with a convex valve seat second step surface.

The rubber diaphragm is provided with cloth or fiber interlayers distributed in the warp and weft directions in the thickness direction.

The suction surface of the movable armature is umbrella-shaped; the umbrella shape is a curved surface formed by connecting a spherical surface and a plurality of conical surfaces.

The valve seat and the plugging port are coaxially sleeved; the gas inlet of the gas inlet channel is provided with a conical hole with a decreasing inner diameter; the transition part of the air inlet channel and the air outlet channel on the plugging port is provided with a curved surface, the curved surface is formed by sequentially and tangentially connecting an intrados surface with a radius R1, a plane with a width S and an extrados surface with a radius R2, and the radius R1 is larger than the radius R2.

The lower yoke is provided with an annular groove around the shaft, a central shaft is formed on the lower yoke after the annular groove is formed, and a central shaft step is formed on the central shaft; the electromagnetic coil consists of a coil framework and a coil fixed on the coil framework; the coil framework is provided with a step hole in interference fit with the central shaft step, and the step hole is used for guaranteeing the installation coaxiality of the electromagnetic coil and the lower yoke.

A magnetism isolating gasket is arranged between the electromagnetic coil and the upper yoke iron; a sealing groove is formed in the contact surface of the upper yoke iron and the magnetism isolating gasket, and a rubber sealing ring is arranged in the sealing groove.

Compared with the prior art, the utility model has the following beneficial effects:

the utility model discloses a high-precision flow control proportional electromagnetic valve, wherein a valve body component is connected with an electromagnet component in a matching way to form a shell and a cavity of the electromagnetic valve, a rubber diaphragm sleeved on an air guide connecting rod is arranged on the matching surface of an upper yoke and a valve seat, the outer ring of the rubber diaphragm is pressed by the upper yoke and the valve seat, the inner ring of the rubber diaphragm is pressed by a circumferential bulge on the air guide connecting rod and a sealing gasket component, the electromagnetic valve cavity is divided into an upper cavity where a movable armature component is positioned and a lower cavity where the sealing gasket component is positioned by the rubber diaphragm, the lower cavity is communicated with an air outlet channel on the valve seat, the upper cavity is communicated with an air inlet channel on a sealing opening through an air guide through hole on the air guide connecting rod, air enters the upper cavity from the air inlet channel, the generated air pressure acts on the upper surface of the rubber diaphragm, which is close to the electromagnet component, part of the generated air pressure acts on the valve core component, the other part acts on the valve seat, and the air pressure component acting on the valve core component acts as a compensation force to enhance the sealing effect of the valve core component.

Further, the diaphragm bottom ring and the diaphragm top ring are respectively arranged on the upper part and the lower part of the outer ring of the rubber diaphragm, and the difference between the inner diameter and the outer diameter of the diaphragm bottom ring is larger than the difference between the inner diameter and the outer diameter of the diaphragm top ring, so that the component force of the gas pressure acting on the valve core assembly is increased, and the pressure resistance of the proportional electromagnetic valve is further enhanced.

Further, a first step surface of the sealing gasket assembly is arranged on the contact surface of the sealing gasket assembly and the inner ring of the rubber diaphragm; the contact surface of the valve seat and the outer ring of the rubber diaphragm is provided with a convex valve seat second step surface, so that the sealing effect of the compression part of the inner ring and the outer ring of the rubber diaphragm can be enhanced.

Further, the rubber diaphragm is provided with cloth or fiber interlayers distributed in the warp-weft direction in the thickness direction, so that the sealing effect and the thickness of the rubber diaphragm are ensured, and meanwhile, the pressure resistance and the service life of the rubber diaphragm are improved.

Further, hysteresis is a main index for reflecting the control precision of the proportional electromagnetic valve, and refers to the ratio of the outlet flow difference to the rated flow of the proportional electromagnetic valve in the same electric signal in the opening and closing processes of the proportional electromagnetic valve, and the hysteresis of the proportional electromagnetic valve can be reduced by reducing the hysteresis effect of an electromagnet and the motion friction of a valve core when the electromagnetic valve is designed; the attraction surface of the movable armature is an umbrella-shaped complex curved surface formed by connecting a spherical surface and a plurality of conical surfaces, so that the influence of the hysteresis effect of the electromagnet on the hysteresis performance of the proportional electromagnetic valve is reduced while the attraction force of the electromagnet of the proportional electromagnetic valve is ensured; meanwhile, the umbrella-shaped complex curved surface of the movable armature makes the contact surface of the movable armature and the gas in the upper cavity form a similar umbrella top structure, so that downward pressure generated by the gas is uniformly distributed on the contact surface of the movable armature, the automatic righting effect is achieved, and the influence of movement friction of the valve core on the hysteresis performance of the proportional electromagnetic valve is reduced.

Further, under the same working pressure, in a certain valve opening range, the outlet flow of the proportional electromagnetic valve and the valve opening are in a proportional relation, wherein the proportional coefficient K is related to the design structure of the flow channel, and generally, the smaller the flow resistance of the flow channel structure is, the larger the proportional coefficient K is, the smaller the vortex generated by the flow channel is, and the more stable the control is. According to the utility model, the gas inlet channel opening of the plugging port is provided with the conical hole, and the transition port of the gas inlet channel and the gas outlet channel is provided with the complex curved surface with a special structure, so that the flow resistance and vortex generation of gas in the proportional electromagnetic valve are effectively reduced, and the control precision and stability of the proportional electromagnetic valve are improved.

Further, a sealing groove for installing a rubber sealing ring is arranged on the contact surface of the upper yoke iron and the magnetism isolating gasket, so that the electromagnetic valve is prevented from leaking.

Drawings

For a clearer description of the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic cross-sectional view of a high-precision flow control proportional solenoid valve according to the present utility model;

FIG. 2 is a schematic diagram of the structure of a moving armature of a high-precision flow control proportional solenoid valve according to the present utility model;

FIG. 3 is a schematic diagram of the distribution of magnetic induction lines between the actuation surface of the moving armature and the electromagnet assembly of the high-precision flow control proportional solenoid valve of the present utility model;

FIG. 4 is a schematic diagram of the air pressure distribution on the air contact surface of the moving armature of the high-precision flow control proportional solenoid valve of the present utility model;

FIG. 5 is a schematic diagram of the seal of the high-precision flow control proportional solenoid valve of the present utility model;

FIG. 6 is a schematic view of a partial structure of an assembly of a rubber diaphragm inner ring of a high-precision flow control proportional solenoid valve according to the present utility model;

FIG. 7 is a schematic view of a partial structure of an assembly of a rubber diaphragm outer ring of a high-precision flow control proportional solenoid valve according to the present utility model;

FIG. 8 is a schematic diagram of an assembled partial structure of a rubber seal ring of the high-precision flow control proportional solenoid valve of the present utility model;

FIG. 9 is a graph comparing the output flow rate with the input electrical signal for a solenoid valve employing an umbrella-top type moving armature and a conventional inverted cone type moving armature for a high-precision flow control proportional solenoid valve in accordance with the present utility model;

FIG. 10 is a graph comparing the output flow rate with the input electrical signal when the ratio of the inner curved surface of the plugging port to the wall thickness of the plugging port is different for the high-precision flow control proportional solenoid valve according to the present utility model.

Wherein: 1-electronic pouring sealant; 2-a lower yoke; 3-electromagnetic coils; 4-magnetism isolating gaskets; 5-a rubber sealing ring; 6-upper yoke; 7-valve seat; 8-a valve seat sealing ring; 9-plugging the mouth; 10-sealing ring of the plugging port; 11-an air inlet channel; 12-an air outlet channel; 13-a gasket assembly; 14-a lower cavity; 15-a diaphragm bottom ring; 16-a rubber diaphragm; 17-a diaphragm top ring; 18-an air guide connecting rod; 19-leaf springs; 20-an air guide through hole; 21-a moving armature; 22-upper cavity; 23-coil frameworks; 24-a power outlet; 25-annular space; 131-a first step surface of the gasket assembly; 132-a gasket; 181-a first step surface of the air guide connecting rod; 201-ring groove; 202-a step shaft; 211-a suction surface; 212-gas contact surface; 213-sphere; 214-a first conical surface; 215-a second conical surface; 231-step hole; 601-upper yoke first step surface; 602-an upper yoke second step surface; 603-upper yoke seal groove; 701-a valve seat first step surface; 702-a valve seat second step surface; 901-a tapered hole; 902-complex curved surfaces.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the embodiments of the present utility model, it should be noted that, if the terms "upper," "lower," "horizontal," "inner," and the like indicate an azimuth or a positional relationship based on the azimuth or the positional relationship shown in the drawings, or the azimuth or the positional relationship in which the inventive product is conventionally put in use, it is merely for convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the apparatus or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the term "horizontal" if present does not mean that the component is required to be absolutely horizontal, but may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the embodiments of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

The utility model is described in further detail below with reference to the attached drawing figures:

referring to fig. 1, the embodiment of the utility model discloses a high-precision flow control proportional electromagnetic valve, which comprises a valve body assembly, an electromagnet assembly and a valve core assembly, wherein the valve body assembly comprises a valve seat 7 and a plugging port 9, the plugging port 9 is positioned at the central position of the valve seat 7, the plugging port 9 is axially provided with an air inlet channel 11 for air inflow, the valve seat 7 takes the plugging port 9 as the center, and a plurality of uniformly distributed air outlet channels 12 are arranged for air outflow;

the electromagnet assembly comprises an upper yoke 6, a lower yoke 2 and an electromagnetic coil 3, wherein a ring groove 201 is formed in the lower yoke 2, the electromagnetic coil 3 is embedded into the ring groove 201, the lower yoke 2 is connected with the upper yoke 6 in an interference fit manner to form a complete magnetic loop, and after the electromagnetic coil is electrified, electromagnetic attraction force is generated to drive the valve core assembly to approach; the other end of the lower yoke 2, which is not provided with a ring groove, is provided with a groove for filling the electronic pouring sealant 1.

The valve core assembly comprises a movable armature 21, a leaf spring 19, an air guide connecting rod 18 and a sealing gasket assembly 13, wherein the other end of the attraction surface of the movable armature 21 is connected with the air guide connecting rod 18 which is axially provided with an air guide through hole 20, and the air guide connecting rod 18 is connected with the sealing gasket assembly 13 which is provided with a sealing gasket 132; the air guide connecting rod 18 is provided with a circumferential bulge, and the matching surface of the circumferential bulge and the movable armature 21 is provided with a leaf spring 19 sleeved on the air guide connecting rod 18 and used for providing sealing force for the valve core assembly towards the plugging port 9; the movable armature 21 and one end of the air guide connecting rod 18 are tightly pressed against the inner ring of the leaf spring 19 through interference fit, the sealing gasket assembly 13 is connected to the valve core assembly through the other end of the air guide connecting rod 18 and used for realizing sealing, and the outer ring of the leaf spring 19 is placed on the first step surface 601 of the upper yoke to deform so as to provide downward sealing force for the valve core assembly;

the valve body assembly is connected with the electromagnet assembly to form a shell and a cavity of the valve; the inner ring of the rubber diaphragm 16 is tightly pressed by the sealing gasket assembly 13 and the first stepped surface 181 of the air guide connecting rod, the cavity is divided into a lower cavity 14 and an upper cavity 22, the lower cavity 14 is directly communicated with the air outlet channel 12, the upper cavity 22 is communicated with the air inlet channel 11 through the air guide through hole 20 on the air guide connecting rod 18, a gas pressure compensation structure is formed, gas enters the upper cavity 22 from the air inlet channel 11, acts on the upper surface of the rubber diaphragm 16, one part of generated gas pressure acts on the valve core assembly, the other part acts on the valve seat 7, and the component of the gas pressure acting on the valve core assembly acts as compensation force for enhancing the sealing effect of the valve core assembly;

the inner hole of the coil framework 23 of the electromagnetic coil 3 is provided with a step hole 231, the central shaft of the lower yoke 2 is provided with a step shaft 202, and the step hole 231 is in interference fit with the step shaft 202 and is used for ensuring the installation coaxiality and the shaking of the electromagnetic coil 3;

referring to fig. 2, 3 and 4, the attraction surface 211 of the movable armature 21, which is close to the electromagnet assembly, is a structure similar to an umbrella top, and the attraction surface 211 is a spherical surface, or a plurality of sections of surfaces connected by a plurality of conical surfaces, or a complex curved surface connected by a plurality of conical surfaces and a spherical surface, so as to reduce the influence of hysteresis effect of the electromagnet on hysteresis performance of a comparative example electromagnetic valve while guaranteeing the attraction effect of the electromagnet assembly; the contact surface 212 of the movable armature 21 and the gas in the lower cavity 22 is umbrella-shaped, the contact surface 212 is a spherical surface, or a plurality of sections of surfaces connected with the conical surface, or a complex curved surface connected with the spherical surface, so that downward pressure generated by the gas is uniformly distributed on the contact surface 212 of the movable armature 21 and the gas, the automatic righting effect is achieved, and the influence of movement friction of a valve core on hysteresis performance of the proportional electromagnetic valve is reduced; hysteresis is a main index for reflecting the control precision of the proportional electromagnetic valve, and refers to the ratio of the outlet flow difference to the rated flow of the proportional electromagnetic valve in the same electric signal in the opening and closing processes of the proportional electromagnetic valve, and the hysteresis of the proportional electromagnetic valve can be reduced by reducing the hysteresis effect of an electromagnet and the motion friction of a valve core when the electromagnetic valve is designed; the attraction surface of the movable armature is an umbrella-shaped complex curved surface formed by connecting a spherical surface and a plurality of conical surfaces, so that the influence of the hysteresis effect of the electromagnet on the hysteresis performance of the proportional electromagnetic valve is reduced while the attraction force of the electromagnet of the proportional electromagnetic valve is ensured; meanwhile, the umbrella-shaped complex curved surface of the movable armature makes the contact surface of the movable armature and the gas in the lower cavity form a similar umbrella top structure, so that downward pressure generated by the gas is uniformly distributed on the contact surface of the movable armature, the automatic righting effect is achieved, and the influence of movement friction of the valve core on the hysteresis performance of the proportional electromagnetic valve is reduced.

Referring to fig. 5, a conical hole 901 is arranged at the inlet channel 11 of the plugging port 9, a complex curved surface 902 with a special structure is arranged at the transition part of the inlet channel 11 and the outlet channel 12, the complex curved surface is formed by sequentially and tangentially connecting an intrados surface with a radius R1, a plane with a width S and an extrados surface with a radius R2, R1 is larger than R2, the curved surface 902 is in contact with the rubber gasket 131 of the gasket assembly 13 to form a sealing structure, and when the curved surface 902 is designed for different task demands, related design requirements are set for some basic dimensions and ratios of the intrados surface, the plane and the extrados surface of the curved surface 902, the wall thickness of the plugging port 9 is T, and the wall thickness of the plugging port 9 is determined by the following method: R1/R2 is more than 1, R1/T=0.55-0.7, and the ratio of R1/T is properly increased, so that the proportionality coefficient of the outlet flow of the proportional electromagnetic valve and the valve opening can be improved; s/t=0.03 to 0.14, and the service life of the rubber gasket of the gasket assembly 13 can be prolonged while ensuring the sealing effect by properly increasing the ratio of S/T; under the same working pressure, in a certain valve opening range, the outlet flow of the proportional electromagnetic valve and the valve opening are in a proportional relation, wherein the proportional coefficient K is related to the design structure of the flow channel, and generally, the smaller the flow resistance of the flow channel structure is, the larger the proportional coefficient K is, the smaller the vortex generated by the flow channel is, and the more stable the control is. According to the utility model, the gas inlet channel opening of the plugging port is provided with the conical hole, and the transition port of the gas inlet channel and the gas outlet channel is provided with the complex curved surface with a special structure, so that the flow resistance and vortex generation of gas in the proportional electromagnetic valve are effectively reduced, and the control precision and stability of the proportional electromagnetic valve are improved.

Referring to fig. 6 and 7, the difference between the inner diameter and the outer diameter of the diaphragm bottom ring 15 is smaller than the difference between the inner diameter and the outer diameter of the diaphragm top ring 17, which is helpful to increase the component force of the gas pressure on the upper surface of the rubber diaphragm 16 acting on the valve core assembly, increase the gas compensation force, and further enhance the pressure resistance of the proportional solenoid valve;

the contact surface of the sealing gasket assembly 13 and the inner ring of the rubber diaphragm 16 is provided with a first convex step surface 131 of the sealing gasket assembly, and the contact surface of the valve seat 7 and the outer ring of the rubber diaphragm 16 is provided with a second convex step surface 702 of the valve seat, so that the sealing effect of the compression parts of the inner ring and the outer ring of the rubber diaphragm is enhanced; the rubber diaphragm 16 is provided with cloth or fiber interlayers distributed in the warp and weft direction in the thickness direction, so that the sealing effect and the thickness of the rubber diaphragm are ensured, and the sealing effect and the service life of the pressing parts of the inner ring and the outer ring of the rubber diaphragm can be enhanced;

referring to fig. 8, the upper yoke 6 is provided with an upper yoke seal groove 603, a magnetism isolating gasket 4 is arranged between the lower yoke 2 and the upper yoke 6, a closed annular space 25 is formed, and a rubber seal ring 5 is arranged in the annular space 25 to prevent gas from flowing out of the upper cavity 22 and causing external leakage of the proportional solenoid valve.

Referring to fig. 9, the closer the curve between the flow lift and the flow drop is, the smaller the hysteresis of the solenoid valve is, and it can be seen that the hysteresis of the proportional solenoid valve is obviously reduced after the umbrella-top type movable armature structure is adopted in the utility model.

Referring to FIG. 10, it is evident that the larger the R1/T ratio, the greater the proportionality coefficient between the outlet flow and the input electrical signal.

The above is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. The high-precision flow control proportional electromagnetic valve is characterized by comprising a valve core assembly, an electromagnet assembly and a valve body assembly; the valve body assembly comprises a valve seat (7) and a plugging port (9); the electromagnet assembly and the valve body assembly are connected in a matched mode to form an electromagnetic valve cavity, and the valve core assembly is arranged in the electromagnetic valve cavity; the valve core assembly comprises a movable armature (21); the other end of the attraction surface of the movable armature (21) is connected with an air guide connecting rod (18) axially provided with an air guide through hole (20), and the air guide connecting rod (18) is connected with a sealing gasket assembly (13); the air guide connecting rod (18) is provided with a circumferential bulge, and the matching surface of the circumferential bulge and the movable armature (21) is provided with a leaf spring (19) sleeved on the air guide connecting rod (18); the valve seat (7) is axially provided with an air outlet channel (12); an air inlet channel (11) is axially arranged on the plugging port (9); when the sealing gasket assembly (13) is attached to the end face of the plugging port (9), the electromagnetic valve is cut off;

the electromagnet assembly comprises a lower yoke (2) and an upper yoke (6) which are connected in a matched manner and provided with an electromagnetic coil (3) in the middle; the electromagnetic coil (3) is used for providing electromagnetic force for driving the valve core assembly to approach after being electrified, and the electromagnetic valve is connected; a rubber diaphragm (16) sleeved on the air guide connecting rod (18) is arranged on the matching surface of the upper yoke (6) and the valve seat (7).

2. The high-precision flow control proportional solenoid valve as claimed in claim 1, wherein an inner ring of the rubber diaphragm (16) is pressed by the circumferential projection and gasket assembly (13), and an outer ring of the rubber diaphragm (16) is pressed by the valve seat (7) and the upper yoke (6).

3. The high-precision flow control proportional solenoid valve as claimed in claim 2, wherein a valve seat first step surface (701) is provided on the valve seat (7), and a diaphragm bottom ring (15) is provided on the valve seat first step surface (701); the upper yoke (6) is sequentially provided with an upper yoke second step surface (602) and an upper yoke first step surface (601) along the direction of fluid entering the electromagnetic valve; a diaphragm top ring (17) is arranged on the second step surface (602) of the upper yoke; the rubber diaphragm (16) is pressed by the diaphragm bottom ring (15) and the diaphragm top ring (17).

4. A high-precision flow control proportional solenoid valve as claimed in claim 3, wherein the difference between the inner diameter and the outer diameter of the diaphragm bottom ring (15) is smaller than the difference between the inner diameter and the outer diameter of the diaphragm top ring (17).

5. A high-precision flow control proportional solenoid valve as claimed in claim 3, wherein a first stepped surface (131) of the gasket assembly is provided on a contact surface of the gasket assembly (13) with an inner ring of the rubber diaphragm (16); the contact surface of the valve seat (7) and the outer ring of the rubber diaphragm (16) is provided with a convex valve seat second step surface (702).

6. The high-precision flow control proportional solenoid valve according to claim 1, wherein the rubber diaphragm (16) has a cloth or fiber sandwich layer with warp and weft distribution in a thickness direction.

7. The high-precision flow control proportional solenoid valve as set forth in claim 1, wherein the actuation surface (211) of the moving armature (21) is umbrella-shaped; the umbrella shape is a curved surface formed by connecting a spherical surface and a plurality of conical surfaces.

8. The high-precision flow control proportional solenoid valve as claimed in claim 1, wherein the valve seat (7) is coaxially sleeved with the plugging port (9); the gas inlet of the gas inlet channel (11) is provided with a conical hole with an inner diameter decreasing gradually; the transition part of the air inlet channel (11) and the air outlet channel (12) on the plugging port (9) is provided with a curved surface (902), the curved surface (902) is formed by sequentially and tangentially connecting an intrados surface with a radius R1, a plane with a width S and an extrados surface with a radius R2, and the radius R1 is larger than the radius R2.

9. The high-precision flow control proportional solenoid valve according to claim 1, wherein the lower yoke (2) is provided with a ring groove (201) around a shaft, a central shaft is formed on the lower yoke (2) after the ring groove is provided, and a central shaft step (202) is arranged on the central shaft; the electromagnetic coil (3) consists of a coil framework (23) and a coil fixed on the coil framework; the coil framework (23) is provided with a step hole (231) in interference fit with the central shaft step (202) for ensuring the installation coaxiality of the electromagnetic coil (3) and the lower yoke (2).

10. The high-precision flow control proportional solenoid valve according to claim 1, wherein a magnetism isolating gasket (4) is provided between the solenoid coil (3) and the upper yoke (6); a sealing groove (603) is formed in the contact surface of the upper yoke (6) and the magnetism isolating gasket (4), and a rubber sealing ring (5) is arranged in the sealing groove (603).