Electronic expansion valve stable in operation

Abstract

The utility model discloses an electronic expansion valve stable in operation, and belongs to the technical field of fluid control. The valve needle assembly mainly comprises a rotor assembly and a valve body assembly, a valve needle body of the valve needle assembly is provided with an annular groove in the surface body of the valve needle body in the circumferential direction, an O-shaped elastic ring is contained in the annular groove, and the annular groove is sleeved with a wear-resisting ring for containing the O-shaped elastic ring in the annular groove in a pressed state. The inner ring of the wear-resisting ring is arranged in the annular groove, and the outer ring of the wear-resisting ring and the inner wall of the lower valve seat are kept in an attached contact state. According to the electronic expansion valve, the phenomenon of blocking is effectively avoided, the operation stability of the electronic expansion valve is obviously improved, and then the stability and continuity of a whole refrigerating system are effectively guaranteed; the improved structure is reasonable and simple in design, easy in product upgrading implementation, low in product upgrading cost, practical and economical, and has positive significance on technical improvement of the electronic expansion valve.

Description

Technical Field

[0001] The utility model belongs to the technical field of fluid control. Specifically, it particularly relates to an electronic expansion valve with stable operation, not interfered by fluid impurities, no "jamming" phenomenon, long service life, and high product quality. Background Art

[0002] As introduced in the background art of the Chinese patent application with the application number 2020102551038: The electronic expansion valve is a component for regulating the refrigerant flow rate in an air-conditioning system. From a functional perspective, the electronic expansion valve mainly consists of a driving component, a transmission component, and a flow regulation component. Generally, the power component includes a stepper motor composed of a stator and a rotor, and a circuit board for controlling the stepper motor; the transmission component includes a screw mechanism and related limiting mechanisms; the flow regulation component includes a flow regulation mechanism composed of a valve needle assembly and a valve seat, and a valve body capable of introducing and discharging fluids, etc.

[0003] The working principle of the electronic expansion valve is as follows: The motor control chip on the circuit board will give a certain pulse to the motor stator according to the command of the superior controller. The motor rotor rotates under the drive of the pulse and drives the moving part in the screw mechanism to rotate around the fixed part in the screw mechanism. Under the action of the thread pair (screw and nut seat), the moving part will move axially while rotating around the fixed part. At the same time, the valve core connected to the moving part will approach or leave the valve seat and simultaneously change the flow area of the valve orifice on the valve seat, so as to achieve the purpose of regulating the refrigerant flow rate passing through the valve orifice. More specifically, after the rotor rotates, it will drive the screw to move up and down relative to the nut seat, and the movement of the screw will drive the valve needle to move in the cavity of the lower valve seat.

[0004] During the refrigeration cycle, the refrigerant will flow from the condenser through the electronic expansion valve to the evaporator. At this time, the refrigerant is in a liquid state or a gas-liquid mixed state, so the internal environment of the electronic expansion valve is humid. This humid environment will cause small impurities in the fluid (such as tiny welding slag in the refrigeration system) to easily adsorb on the inner wall of the cavity of the lower valve seat. Due to certain allowable errors inevitably existing in mechanical processing, there will naturally be a certain gap between the nut seat and the screw. Therefore, when the rotor rotates, the movement of the screw in the nut seat will produce slight shaking, which will further cause the valve needle to also produce slight shaking in the cavity of the lower valve seat. This slight shaking will cause the impurities adsorbed on the inner wall of the cavity to get stuck between the valve needle and the inner wall of the cavity of the lower valve seat, and ultimately may lead to the occurrence of the "jamming" phenomenon. Seriously affecting the stability of product operation, the quality and service life of the product cannot be effectively guaranteed. Summary of the Utility Model

[0005] The purpose of the present utility model is to provide an electronic expansion valve with stable operation, not interfered by fluid impurities, without "jamming" phenomenon, long service life, and high product quality in view of the deficiencies existing in the prior art.

[0006] The present utility model is achieved through the following technical solutions:

[0007] An electronic expansion valve with stable operation, comprising a rotor assembly and a valve body assembly hermetically and fixedly connected to the rotor assembly. The rotor assembly includes a valve needle assembly with its end extending into the lower valve seat cavity. It is characterized in that: the valve needle of the valve needle assembly includes a valve needle tip adapted to the valve orifice of the lower valve seat and a valve needle body integrally fixed with the valve needle tip; a circumferential annular groove is formed on the surface of the valve needle body along the circumferential direction, and an O-ring elastic ring is accommodated in the annular groove. A wear-resistant ring is sleeved outside the annular groove to accommodate the O-ring elastic ring in a compressed state in the annular groove, and the inner ring of the wear-resistant ring is in the annular groove, and the outer ring of the wear-resistant ring is in close contact with the inner wall of the lower valve seat.

[0008] Preferably, the material of the O-ring elastic ring is nitrile rubber, and the material of the wear-resistant ring is polytetrafluoroethylene.

[0009] Preferably, the height of the wear-resistant ring is equivalent to the height dimension of the annular groove.

[0010] Preferably, the annular groove is arranged at the lower position of the valve needle body.

[0011] Preferably, the area between the bottom of the annular groove and the end face of the valve needle body is in the shape of an inverted frustum or a combination shape of a column and an inverted frustum.

[0012] Preferably, the rotor assembly further includes an upper valve seat fixedly connected to the lower valve seat. A valve sleeve is fixedly connected to the upper valve seat. A nut seat fixedly connected to the upper valve seat is arranged in the valve sleeve. A guide rail spring around which a stop ring is wound is fixedly installed on the nut seat. The valve needle assembly is threadedly connected in the nut seat. The upper end of the screw of the valve needle assembly is fixedly connected to the rotor embedded in the valve sleeve through a rotor connecting piece, and the rotor connecting piece is also fixedly connected to a stop rod for pushing the stop ring.

[0013] Preferably, the valve body assembly includes a valve body provided with a gas inlet and outlet one, a gas inlet and outlet two, an upper valve seat installation cavity, and a lower valve seat accommodation cavity. The lower valve seat is provided with a plurality of gas circulation ports along the circumferential direction. After the lower valve seat is accommodated in the lower valve seat accommodation cavity, the gas inlet and outlet one is communicated with the cavity of the lower valve seat, and the gas inlet and outlet two is communicated with the valve orifice of the lower valve seat.

[0014] Preferably, the rotor assembly and the valve body assembly are fixedly connected through a valve seat fixing ring.

[0015] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0016] The utility model effectively avoids the occurrence of the "jamming" phenomenon, significantly improves the operation stability of the electronic expansion valve, and thus effectively ensures the stability and continuity of the entire refrigeration system;

[0017] The utility model is durable and has a long service life. Its good stability and high reliability significantly improve the competitiveness of the product in the market and user satisfaction;

[0018] The utility model effectively reduces the maintenance and replacement frequency of the product, saving maintenance costs for users;

[0019] The improved structural design of the utility model is reasonable and concise. The product upgrade is easy to implement, with low product upgrade costs. It is practical and economical, and has positive significance for the technical improvement of the electronic expansion valve. Description of the Drawings

[0020] Figure 1 is a schematic three-dimensional structure diagram of the utility model Figure 1 .

[0021] Figure 2 is a schematic three-dimensional structure diagram of the utility model Figure 2 .

[0022] Figure 3 is a schematic diagram of the structure of the valve needle assembly of the utility model.

[0023] Figure 4 is a schematic diagram of the structure in the side view direction of the utility model.

[0024] Figure 5 is the utility model Figure 4 is a schematic cross-sectional structure diagram along the A-A direction.

[0025] Figure 6 is the utility model Figure 5 is an enlarged view at B in the figure.

[0026] In the figure: 1. Rotor assembly; 11. Valve sleeve; 12. Nut seat; 13. Retaining ring; 14. Guide rail spring; 15. Valve needle assembly; 151. Valve needle; 1511. Valve needle tip; 1512. Valve needle body; 1513. Annular groove; 1514. O-ring; 1515. Wear-resistant ring; 152. Screw; 16. Rotor connecting piece; 17. Rotor; 18. Upper valve seat; 19. Lower valve seat; 192. Flow port; 2. Valve body assembly; 21. Valve body; 211. Gas inlet and outlet one; 212. Gas inlet and outlet two; 214. Lower valve seat accommodating cavity; 3. Valve seat fixing ring. Detailed Implementation Modes

[0027] The present utility model will be further described below in conjunction with the accompanying drawings:

[0028] Embodiment 1

[0029] As Figure 3 、 Figure 5 、 Figure 6 shown, a stable-running electronic expansion valve includes a rotor assembly 1 and a valve body assembly 2 hermetically and fixedly connected to the rotor assembly 1. The rotor assembly 1 includes a valve needle assembly 15 with its end extending into the cavity of the lower valve seat 19. The valve needle 151 of the valve needle assembly 15 includes a valve needle tip 1511 adapted to the valve port of the lower valve seat 19 and a valve needle body 1512 integrally fixed with the valve needle tip 1511. The valve needle body 1512 is provided with an annular groove 1513 on its surface in the circumferential direction. An O-ring 1514 is accommodated in the annular groove 1513. A wear-resistant ring 1515 is sleeved outside the annular groove 1513 to accommodate the O-ring 1514 in a compressed state in the annular groove 1513. The inner ring of the wear-resistant ring 1515 is in the annular groove 1513, and the outer ring of the wear-resistant ring 1515 is in close contact with the inner wall of the lower valve seat 19.

[0030] In this embodiment, the wear-resistant ring 1515 is made of a wear-resistant material with a small coefficient of friction. When the electronic expansion valve works, the valve needle assembly 15 moves up and down in the cavity of the lower valve seat 19. The O-ring 1514 has elasticity, and it can make the wear-resistant ring 1515 keep in close contact with the inner wall of the cavity of the lower valve seat 19 in a circumferential circle in the annular groove 1513. This design makes it impossible for tiny impurities to adsorb on the inner wall of the cavity of the lower valve seat 19 above the wear-resistant ring 1515, and they will only adsorb on the inner wall of the cavity of the lower valve seat 19 below the wear-resistant ring 1515. The annular groove 1513 is opened as close as possible to the lower position of the valve needle body 1512. When the wear-resistant ring 1515 moves downward, it will scrape off the impurities adsorbed on the inner wall of the cavity of the lower valve seat 19, so that the impurities will flow away with the fluid and will not get stuck between the valve needle and the inner wall of the cavity of the lower valve seat. Thus, the occurrence of the "jamming" phenomenon is effectively avoided.

[0031] This embodiment effectively avoids the occurrence of the "jamming" phenomenon, significantly improves the running stability of the electronic expansion valve, and further effectively guarantees the stability and continuity of the entire refrigeration system;

[0032] This embodiment is durable and has a long service life. Its good stability and high reliability significantly improve the competitiveness of the product in the market and user satisfaction;

[0033] This embodiment effectively reduces the maintenance and replacement frequency of the product, saving maintenance costs for users;

[0034] The improved structure design of this embodiment is reasonable and concise, the product upgrade is easy to implement, the product upgrade cost is low, it is practical and economical, and it has positive significance for the technical improvement of the electronic expansion valve.

[0035] Embodiment 2

[0036] Based on Embodiment 1, this embodiment continues to describe in detail the technical features involved and the functions and roles played by these technical features in the present utility model, so as to help those skilled in the art fully understand the technical solution of the present utility model and reproduce it.

[0037] An electronically controlled expansion valve with stable operation, comprising a rotor assembly 1 and a valve body assembly 2 hermetically and fixedly connected to the rotor assembly 1. The rotor assembly 1 includes a valve needle assembly 15 whose end extends into the cavity of the lower valve seat 19. The valve needle 151 of the valve needle assembly 15 includes a valve needle tip 1511 adapted to the valve port of the lower valve seat 19 and a valve needle body 1512 integrally fixed with the valve needle tip 1511. An annular groove 1513 is formed in the circumferential direction on the surface of the valve needle body 1512. An O-ring 1514 is accommodated in the annular groove 1513. A wear-resistant ring 1515 is sleeved outside the annular groove 1513 to accommodate the O-ring 1514 in a compressed state in the annular groove 1513. The inner ring of the wear-resistant ring 1515 is in the annular groove 1513, and the outer ring of the wear-resistant ring 1515 is in close contact with the inner wall of the lower valve seat 19. The material of the O-ring 1514 is nitrile rubber, which has strong elasticity and wear and chemical corrosion resistance characteristics, and is the preferred material for O-rings; the material of the wear-resistant ring 1515 is polytetrafluoroethylene, which has a small friction coefficient and wear and chemical corrosion resistance characteristics, and is the preferred material for wear-resistant rings. In this embodiment, the height of the wear-resistant ring 1515 is equivalent to the groove height of the annular groove 1513, and the wear-resistant ring 1515 is stably assembled with the annular groove 1513. The annular groove 1513 is provided at the lower position of the valve needle body 1512, and the so-called lower position means the position close to the end of the valve needle body 1512. The area between the bottom of the annular groove 1513 and the end face of the valve needle body 1512 is in the shape of an inverted frustum or a combination of a columnar shape and an inverted frustum shape. The inverted frustum shape can prevent the valve needle body 1512 below the wear-resistant ring 1515 from being "stuck" with the inner wall of the cavity of the lower valve seat 19. If only the inverted frustum shape is adopted, its mechanical strength is not as good as the combined shape. Of course, when adopting the combined shape of a columnar shape and an inverted frustum shape, the height of the columnar shape should not be too high to prevent impurities with a comparable gap from just getting stuck in the gap between the columnar shape and the inner wall of the lower valve seat 19. The combined shape design of the columnar shape and the inverted frustum shape not only ensures the mechanical strength of the valve needle body but also basically reduces the probability of "jamming" to zero.

[0038] Embodiment 3

[0039] AsFigures 1 to 6 As shown, on the basis of Embodiment 2, the rotor assembly 1 of this embodiment further includes an upper valve seat 18 fixedly connected to the lower valve seat 19. The upper valve seat 18 is fixedly connected with a valve sleeve 11. Inside the valve sleeve 11, there is a nut seat 12 fixedly connected to the upper valve seat 18. On the nut seat 12, a guide rail spring 14 around which a stop ring 13 is wound is fixedly installed. A valve needle assembly 15 is threadedly connected inside the nut seat 12. The upper end of the screw rod 152 of the valve needle assembly 15 is fixedly connected to the rotor 17 embedded in the valve sleeve 11 through a rotor connecting piece 16. The rotor connecting piece 16 is also fixedly connected with a stop rod for pushing the stop ring 13. The valve body assembly 2 includes a valve body 21 provided with a gas inlet and outlet one 211, a gas inlet and outlet two 212, an upper valve seat installation cavity, and a lower valve seat accommodation cavity 214. The lower valve seat 19 is provided with a plurality of flow ports 192 for gas circulation along the circumferential direction. After the lower valve seat 19 is accommodated in the lower valve seat accommodation cavity 214, the gas inlet and outlet one 211 is communicated with the cavity of the lower valve seat 19, and the gas inlet and outlet two 212 is communicated with the valve port of the lower valve seat 19. The rotor assembly 1 and the valve body assembly 2 are fixedly connected through a valve seat fixing ring 3. The specific operation process of the rotor assembly 1 and the valve body assembly 2 in this embodiment is prior art. To avoid cumbersome writing, it will not be elaborated. When the electronic expansion valve needs to open the valve port, the rotor 17 of this embodiment rotates to drive the valve needle assembly 15 to move upward. The wear-resistant ring 1515 has a small coefficient of friction, and the valve needle body 1512 moves stably and freely inside the cavity of the lower valve seat 19. When it is necessary to close the valve port, the rotor 17 rotates in the reverse direction to drive the valve needle assembly 15 to move downward. When the wear-resistant ring 1515 moves downward, it scrapes off the small impurities adsorbed on the inner wall of the cavity of the lower valve seat 19. The pushed-down small impurities are carried away from the gas inlet and outlet one 211 or the gas inlet and outlet two 212 under the action of the fluid.

[0040] In summary, the above are only the preferred embodiments of the present invention, and are not used to limit the scope of implementation of the present invention. All equivalent changes and modifications made according to the shape, structure, features, and spirit of the scope of the claims of the present invention should be included within the scope of the claims of the present invention.

Claims

1. An electronic expansion valve with stable operation, comprising a rotor assembly (1) and a valve body assembly (2) sealed and fixedly connected to the rotor assembly (1), wherein the rotor assembly (1) comprises a valve needle assembly (15) whose end extends into a cavity of a lower valve seat (19), and characterized in that: The valve needle (151) of the valve needle assembly (15) comprises a valve needle tip (1511) adapted to the valve port of the lower valve seat (19), and a valve needle body (1512) fixed integrally with the valve needle tip (1511); the valve needle body (1512) is provided with an annular groove (1513) on the surface of the valve needle body (1512) along the circumferential direction, an O-type elastic ring (1514) is accommodated in the annular groove (1513), and a wear-resistant ring (1515) is provided on the outer cover of the annular groove (1513) for accommodating the O-type elastic ring (1514) in a pressurized state in the annular groove (1513), and the inner ring of the wear-resistant ring (1515) is in the annular groove (1513), and the outer ring of the wear-resistant ring (1515) maintains a close contact state with the inner wall of the lower valve seat (19).

2. The electronic expansion valve with stable operation according to claim 1, characterized in that: The material of the O-type elastic ring (1514) is nitrile rubber, and the material of the wear-resistant ring (1515) is polytetrafluoroethylene.

3. An electronic expansion valve with stable operation according to claim 1 or 2, characterized in that: The height of the wear-resistant ring (1515) is comparable to the height of the annular groove (1513).

4. The electronic expansion valve with stable operation according to claim 1, characterized in that: The annular groove (1513) is arranged below the valve needle body (1512).

5. The electronic expansion valve with stable operation according to claim 4, characterized in that: The area between the groove bottom of the annular groove (1513) and the end surface of the valve needle body (1512) is in the shape of an inverted truncated cone or a combination of a columnar shape and an inverted truncated cone.

6. The electronic expansion valve with stable operation according to claim 1, characterized in that: The rotor assembly (1) further comprises an upper valve seat (18) fixedly connected to the lower valve seat (19), the upper valve seat (18) being fixedly connected to a valve sleeve (11), a nut seat (12) being fixedly connected to the upper valve seat (18) being provided in the valve sleeve (11), a guide spring (14) having a stop ring (13) wound therearound being fixedly mounted on the nut seat (12), the valve needle assembly (15) being internally threadedly connected to the nut seat (12), the upper end of a screw rod (152) of the valve needle assembly (15) being fixedly connected to a rotor (17) embedded in the valve sleeve (11) via a rotor connecting piece (16), the rotor connecting piece (16) being further fixedly connected to a stop rod for pushing the stop ring (13).

7. The electronic expansion valve with stable operation according to claim 1, characterized in that: The valve body assembly (2) comprises a valve body (21) having a first gas inlet and outlet (211), a second gas inlet and outlet (212), an upper valve seat installation cavity and a lower valve seat accommodating cavity (214); the lower valve seat (19) has a plurality of flow openings (192) for gas circulation along a circumferential direction; after the lower valve seat (19) is accommodated in the lower valve seat accommodating cavity (214), the first gas inlet and outlet (211) is communicated with the cavity of the lower valve seat (19), and the second gas inlet and outlet (212) is communicated with the valve port of the lower valve seat (19).

8. The electronic expansion valve with stable operation according to claim 1, characterized in that: The rotor assembly (1) and the valve body assembly (2) are fixedly connected via a valve seat fixing ring (3).

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