CN218935404U - Needle type high-low pressure switching valve - Google Patents

Abstract

The utility model discloses a needle type high-low pressure switching valve, wherein a cavity is arranged in a valve body, a valve core is arranged in the cavity and can move up and down in the cavity, the lower end of the left side of the cavity is communicated with a fluid inlet, the lower end of the right side of the cavity is communicated with a fluid outlet, the upper end of the valve core is connected with an elastic piece, the middle part of the valve core is provided with a valve core channel, and fluid can flow into the upper end of the cavity from the lower end of the cavity through the valve core channel and exert downward hydraulic pressure on the valve core. Fluid flows into a cavity above the valve core through the valve core channel, the valve value (switching value) of the valve is determined by the elastic force of the elastic piece, when the hydraulic pressure above the valve is larger than the preset valve value, the valve core is pushed to move downwards by overcoming the elastic force of the elastic piece by the hydraulic pressure, a fluid passage is blocked, a high-pressure environment and a low-pressure environment are isolated, a low-range high-precision instrument can normally operate without bursting of the meter, the whole valve is driven by the hydraulic pressure only, manual switching is not needed, and the response speed is high.

Description

Needle type high-low pressure switching valve

Technical Field

The utility model relates to the technical field of valves, in particular to a needle type high-low pressure switching valve.

Background

In the pressure test, a test piece needs to perform low-pressure test, high-pressure test and the like according to certain requirements, and in the same test pipeline, the high-pressure sampling point and the low-pressure sampling point have larger phase difference, and the high-pressure gauge or the sensor has a larger measuring range, so that the precision is very low under the condition of detecting the low pressure, and the pressure gauge or the sensor close to the sampling point needs to be adopted to obtain a high-precision display of the sampling point, namely a low-range high-precision instrument. However, if the low-range high-precision instrument is directly connected with high-pressure fluid, the low-pressure instrument is not subjected to high pressure and is exploded, so that the low-pressure instrument is isolated from high pressure during detection.

In the patent application CN95241868.1, an isolation valve is typically used to isolate the high-pressure fluid from the low-pressure meter or sensor in the high-pressure pipeline. However, the structure needs complicated mechanical mechanism detection feedback, and a circuit is matched to control the valve switch to achieve an isolation effect, so that the steps are complicated. And if manual switching is adopted, the switching precision or the quick response is poor, so that the low-pressure manometer and the sensor are damaged by the overpressure. The isolating valve on the market at present is difficult to realize automatic switching and ensure switching precision under an explosion-proof environment.

Disclosure of Invention

Accordingly, in order to solve the above-mentioned problems, an object of the present utility model is to provide a needle type high-low pressure switching valve, which replaces the conventional isolation valve.

The utility model provides a needle type high-low pressure switching valve, wherein a cavity is arranged in a valve body, a valve core is arranged in the cavity and can move up and down in the cavity, and the needle type high-low pressure switching valve is characterized in that the lower end of the cavity is communicated with a fluid inlet and a fluid outlet, the height of the fluid outlet is higher than that of the fluid inlet, the upper end of the valve core is connected with an elastic piece, the elastic piece is used for limiting the downward movement of the valve core, a valve core channel is arranged in the middle of the valve core, fluid can flow into the upper end of the cavity from the lower end of the cavity through the valve core channel and exert downward pressure on the valve core, and the conduction between the fluid inlet and the fluid outlet is controlled by changing the position of the lower end of the valve core.

Preferably, the cavity is divided into an upper cavity, a middle cavity and a lower cavity from top to bottom, the middle cavity is communicated with the atmosphere through a through hole, fluid can flow into the upper cavity through a valve core channel from the lower cavity, a middle sealing element is arranged between the upper cavity and the middle cavity, and a lower sealing element is arranged between the middle cavity and the lower cavity.

Preferably, the upper end of case upper segment is fixed with the connecting rod, and the valve body is stretched out to the connecting rod upper end, the upper end of connecting rod is equipped with the stopper, the elastic component is the spring, the spring cover is established on the connecting rod and the spring setting is between the upper surface of stopper and valve body.

Preferably, a lock nut is arranged at the upper end of the upper cavity, the lock nut is in threaded connection with the valve body, and the connecting rod penetrates through the lock nut.

Preferably, the spring protection device further comprises a protection shell, wherein the protection shell is arranged on the outer side of the spring and used for protecting the spring.

Preferably, an adjusting nut is arranged between the limiting block and the upper end of the spring and is in threaded connection with the connecting rod, and the compression amount of the spring can be changed by adjusting the position of the adjusting nut.

Preferably, an upper sealing element is arranged between the connecting rod and the locking nut.

The beneficial effects of the utility model are as follows:

the valve core is arranged in the cavity of the valve body, the upper end of the valve core is connected with the elastic piece, the elastic piece applies upward elastic force to the valve core, the middle part of the valve core is provided with a valve core channel which is penetrated up and down, fluid flows into the cavity above the valve core through the valve core channel, at the moment, the fluid applies downward pressure to the valve core, when high-pressure fluid flows in, the downward pressure born by the valve core is larger than the upward elastic force applied by the elastic piece, the valve core moves downwards, a fluid passage can be blocked, the valve value of the valve is determined by the elastic force of the elastic piece, the high-pressure environment and the low-pressure environment are isolated, the instrument with low measuring range and high precision can normally operate without bursting a meter, the whole valve is driven by hydraulic pressure only, manual switching is not needed, and the valve has a simple structure and high response speed.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic view of the valve in the closed state;

FIG. 3 is a schematic view of the structure of the valve in an open state;

FIG. 4 is a schematic view of the structure of the valve body;

reference numerals illustrate: 1. a valve body; 2. a valve core; 21. a connecting rod; 22. a limiting block; 3. a lower seal; 4. a middle seal; 5. a lock nut; 6. an upper seal; 7. a spring; 8. an adjusting nut; 9. a protective shell; 10. a fluid inlet; 11. a fluid outlet; 12. a valve body stop surface; 13. a lower cavity; 14. a middle cavity; 15. an upper cavity; 16. and a valve core channel.

The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The technical solutions in 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.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to 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 terms in this application will be understood by those of ordinary skill in the art in a specific context.

Examples:

fig. 1-4 show a needle type high-low pressure switching valve provided by the utility model, which comprises a valve body 1, a valve core 2 and a lock nut 5, wherein a cavity is arranged in the valve body 1, the valve core 2 is arranged in the cavity, the cavity is divided into an upper cavity 15, a middle cavity 14 and a lower cavity 13 from top to bottom, the upper cavity 15, the middle cavity 14 and the lower cavity 13 are not communicated with each other, the lock nut 5 is fastened at the upper end of the valve body 1 through screw fit, the middle cavity 14 is communicated with the atmosphere through a through hole, the left side of the lower cavity 13 is communicated with a fluid inlet 10, the right side is communicated with a fluid outlet 11, the height of the fluid outlet 11 is higher than the height of the fluid inlet 10, the fluid inlet 10 and the fluid outlet 11 are both communicated with the lower cavity 13, the middle part of the valve core 2 is provided with a valve core channel 16, fluid passing through the valve core channel 2 from top to bottom and flowing from the lower cavity 13 to the upper cavity 15, the upper end of the valve core 2 is fixedly provided with a connecting rod 21, the upper end of the connecting rod 21 passes through the lock nut 5 and stretches out of the valve body 1, the upper end of the connecting rod 21 is fixedly connected with a limiting block 22 and a spring 7 is fixedly arranged between the upper surface of the upper end of the valve body 7 and the valve body 7.

The valve core 2 is divided into an upper valve core section, a middle valve core section and a lower valve core section, the diameters of which are gradually decreased, wherein the upper valve core section and the middle valve core section are tightly adhered to the cavity and divide the cavity into an upper cavity 15, a middle cavity 14 and a lower cavity 13, specifically, the upper surface of the upper valve core section and the cavity form the upper cavity 15, the lower surface of the upper valve core section, the side surface of the middle valve core section and the cavity form the middle cavity 14, and the cavity part below the middle valve core section is the lower cavity 13.

A valve body stop surface 12 is arranged in the lower cavity 13, the height of the stop is higher than that of the fluid inlet 10 and lower than that of the fluid outlet 11, and the valve body stop surface 12 can block the passage of the fluid inlet 10 flowing to the fluid outlet 11; the valve core 2 is arranged in the cavity and can move up and down in the cavity, the lower end of the valve core 2 is provided with a valve core stop surface matched with the valve body stop surface 12, when the valve body stop surface 12 is matched with the valve core stop surface, a fluid passage is blocked, and liquid in the fluid inlet 10 can not flow into the fluid outlet 11 from a gap between the valve core 2 and the cavity.

When fluid flows into the upper cavity 15 from the lower cavity 13 through the valve core channel 16, the upper cavity 15 is filled, the annular cavity area of the upper cavity 15 is larger than the lower cavity 13 area of the lower end of the valve core, the hydraulic pressure in the upper cavity 15 applies downward thrust to the upper end of the valve core 2, the connecting rod 21 and the limiting block 22 move downwards along with the valve core 2, the limiting block 22 presses the spring 7 to compress the spring 7, the spring 7 applies upward elastic force to the valve core 2, when the hydraulic pressure applied to the valve core 2 in the upper cavity 15 is larger than the elastic force of the spring 7, the valve core 2 moves downwards until the valve core cut-off surface of the valve core 2 abuts against the valve body cut-off surface 12, the passage between the fluid inlet 10 and the fluid outlet 11 is blocked, and the above-mentioned middle cavity 14 is communicated with the atmosphere through the through hole, so that the purpose is that the air pressure in the middle cavity 14 is always equal to the air pressure, the hydraulic pressure in the upper cavity 15 is larger than the air pressure in the middle cavity 14, the movement of the valve core 2 is not blocked.

In this embodiment, the connecting rod 21 is coaxial with the valve core channel 16, the position of the connecting rod 21 blocks the upper end opening of the valve core channel, and the valve core channel 16 needs to provide a passage for fluid to flow from the lower cavity 13 to the upper cavity 15, so the upper section of the valve core is provided with a diversion hole, the diversion hole is communicated with the valve core channel 16, and the position of the connecting rod 21 is avoided, so that the fluid can smoothly flow through the valve core channel 16 and the diversion hole from the lower cavity 13 to enter the upper cavity 15.

The upper end of the upper cavity 15 is provided with a lock nut 5, the lock nut 5 is provided with external threads, the upper end of the valve body 1 is provided with internal threads, the lock nut 5 is in threaded fit with the upper end of the valve body 1, the upper end of the connecting rod 21 passes through the lock nut 5, the lock nut 5 seals the upper end opening of the upper cavity 15, and the upper cavity 15 is sealed, so that the upper cavity 15 is communicated with the lower cavity 13 only through the valve core channel 16.

In order to facilitate the processing and forming, the diameters of the upper cavity 15, the middle cavity 14 and the lower cavity 13 decrease in sequence, and the upper cavity 15 must be opened, so the embodiment selects the lock nut 5 to seal the opening of the upper cavity 15 according to the actual situation, and other parts which can seal the opening of the upper cavity 15 and fix the valve body 1 can also replace the lock nut 5.

Since the lock nut 5 is positioned instead of the upper end of the valve body 1, the lower end of the spring 7 abuts against the upper end of the lock nut 5.

The spring 7 is not exposed to the external space, so the protection shell 9 is additionally arranged for protecting the spring 7, the protection shell 9 covers the connecting rod 21 and the limiting block 22 and protects the connecting rod 21 and the limiting block 22 together, and the protection shell 9 is in threaded connection with the lock nut 5 in the embodiment.

The upper end threaded connection of connecting rod 21 has adjusting nut 8, twists adjusting nut 8 adjustment position can change the compression volume of spring 7 to change the threshold of valve, specifically, when adjusting nut 8 moves down and changes the position, spring 7 compression volume increases, needs bigger hydraulic pressure to overcome elasticity and makes case 2 move down, and the threshold of valve improves promptly, otherwise, when adjusting nut 8 moves up and changes the position, spring 7 compression volume reduces, overcomes that the hydraulic pressure that the elasticity needs is less, the threshold of valve reduces, adjusting nut 8 moves to the uppermost time and can be blocked by stopper 22, can not break away from connecting rod 21.

The upper cavity 15, the middle cavity 14 and the lower cavity 13 all have the requirement of relative sealing, the only passage of the upper cavity 15 is communicated with the lower cavity 13 through the valve core channel 16, the middle cavity 14 is communicated with the outside atmosphere, the lower cavity 13 has the relatively complex requirement, on one hand, the upper cavity 15 is communicated with the valve core channel 16, on the other hand, the fluid inlet 10 and the fluid outlet 11 are required to be ensured to be switched under the two states of communication and blocking, and a sealing element is required to be arranged at a specific position, so that the relative sealing performance of the whole cavity is ensured. Specifically, an upper sealing element 6 is arranged between the lock nut 5 and the connecting rod 21, the upper sealing element 6 seals a gap between the connecting rod 21 and the middle part of the lock nut 5 to prevent liquid from flowing out, and the gap between the lock nut 5 and the valve body 1 is sealed in advance, so that a special sealing element is not required; a middle sealing element 4 is arranged between the valve core 2 and the middle cavity 14, and the middle sealing element 4 is used for preventing the communication between the middle cavity 14 and the upper cavity 15, so that the liquid in the upper cavity 15 flows into the middle cavity 14 and then flows into the external atmosphere; a lower sealing element 3 is arranged between the valve core 2 and the lower cavity 13, the lower sealing element 3 is used for preventing communication between the lower cavity 13 and the middle cavity 14, and the position where the lower sealing element 3 is arranged cannot influence the normal use of the fluid outlet 11.

When the valve is closed, the fluid inlet 10 is in a high-pressure environment, the fluid outlet is in a low-pressure environment, the hydraulic pressure of the high-pressure environment is about 3-5 MPa, and the hydraulic pressure of the low-pressure environment is about 0.5-1 MPa.

The fluid mentioned in this embodiment is not limited to liquid, but may be high-pressure gas, so long as the gas pressure is greater than atmospheric pressure, so as to satisfy the use foundation of the valve, and the valve may be used to achieve the effect of the valve.

Working principle:

under the condition of normal circulation, the fluid is divided into two paths, and the detailed description is shown in the path A of FIG. 3: liquid enters the valve from the fluid inlet 10, flows through the lower cavity 13 and flows into the fluid outlet 11; and (B) path: the liquid flows from the fluid inlet 10 into the cartridge channel 16 and then from the upper end of the cartridge channel 16 into the upper chamber 15.

Because the annular cavity area of the upper cavity 15 is larger than the lower cavity 13 area of the lower end of the valve core, when the hydraulic pressure is larger and reaches a preset threshold value (switching value), the hydraulic pressure in the upper cavity 15 overcomes the elasticity of the spring 7 to apply downward pushing force to the valve core 2, the valve core 2 gradually moves downwards until the valve core 2 blocks the path A, the original path is divided into a fluid inlet 10 and a fluid outlet 11, the liquid hydraulic pressure of the fluid outlet 11 is small, a low-range high-precision pressure gauge or a sensor is communicated with the fluid outlet 11, the pressure of the fluid outlet 11 cannot be increased according to the increase of the hydraulic pressure of the fluid inlet 10, and the switching valve plays a role in automatically protecting a low-range instrument; when the pressure of the fluid inlet 10 is smaller than the threshold value, the elasticity of the spring 7 overcomes the reduced hydraulic pressure to push the valve core 2 upwards, and the fluid inlet 10 is communicated with the fluid outlet 11.

The foregoing description is only of the optional embodiments of the present utility model, and is not intended to limit the scope of the utility model, and all the equivalent structural changes made by the description of the present utility model and the accompanying drawings or the direct/indirect application in other related technical fields are included in the scope of the utility model.

Claims (7)

1. The utility model provides a high low pressure switching valve of needle type, includes valve body (1) and case (2), be equipped with the cavity in the valve body, case (2) set up in the cavity and can reciprocate in the cavity, its characterized in that, cavity lower extreme intercommunication has fluid inlet (10) and fluid outlet (11), and the height of fluid outlet (11) is higher than fluid inlet (10), the upper end and the elastic component of case (2) are connected, and the elastic component is used for restricting the downward movement of case (2), the middle part of case (2) is equipped with case passageway (16), and fluid can flow into cavity upper end and exert decurrent pressure to the case by cavity lower extreme through case passageway (16), controls the switch-on of fluid inlet (10) and fluid outlet (11) through the position of change case (2) lower extreme.

2. Needle high-low pressure switching valve according to claim 1, characterized in that the cavity is divided into an upper cavity (15), a middle cavity (14) and a lower cavity (13) from top to bottom, the middle cavity (14) is communicated with the atmosphere through a through hole, fluid can flow into the upper cavity (15) from the lower cavity (13) through a valve core channel (16), a middle sealing element (4) is arranged between the upper cavity (15) and the middle cavity (14), and a lower sealing element (3) is arranged between the middle cavity (14) and the lower cavity (13).

3. The needle type high-low pressure switching valve according to claim 2, wherein a connecting rod (21) is fixed at the upper end of the upper section of the valve core, the upper end of the connecting rod (21) extends out of the valve body (1), a limiting block (22) is arranged at the upper end of the connecting rod (21), the elastic piece is a spring (7), the spring (7) is sleeved on the connecting rod (21), and the spring (7) is arranged between the limiting block (22) and the upper surface of the valve body (1).

4. A needle type high-low pressure switching valve according to claim 3, characterized in that the upper end of the upper cavity (15) is provided with a lock nut (5), the lock nut (5) is in threaded connection with the valve body (1), and the connecting rod (21) passes through the lock nut (5).

5. A needle high-low pressure switching valve according to claim 3, further comprising a protective housing (9), said protective housing (9) being arranged outside the spring (7) for protecting the spring (7).

6. A needle type high-low pressure switching valve according to claim 3, characterized in that an adjusting nut (8) is arranged between the limiting block (22) and the upper end of the spring (7), the adjusting nut (8) is in threaded connection with the connecting rod (21), and the compression amount of the spring (7) can be changed by adjusting the position of the adjusting nut (8).

7. A needle high-low pressure switching valve according to claim 3, characterized in that an upper seal (6) is provided between the connecting rod (21) and the lock nut (5).

Images