Electronic expansion valve and air conditioner

Abstract

The electronic expansion valve comprises a valve body and a valve needle located in the valve body, a flow inlet channel and a flow outlet channel are formed in the valve body, the flow inlet channel and the flow outlet channel are communicated through a valve hole, the valve needle can adjust the opening degree of the valve hole, the diameter of the valve hole is Dc, and the diameter of the valve hole is Dc. The height of the valve hole in the axial direction of the valve needle is Hc, and Hc / Dc is larger than 0.25 and smaller than 1.5. According to the electronic expansion valve, by limiting the ratio of the height Hc of the valve hole to the diameter Dc of the valve hole, it can be guaranteed that noise of the designed electronic expansion valve is at a low level, the overall dimension of the valve body of the electronic expansion valve is slightly changed or even does not need to be changed, and the requirement for manufacturing work is relatively low.

Description

Technical Field

[0001] This utility model belongs to the field of air conditioning technology, specifically relating to an electronic expansion valve and an air conditioner. Background Technology

[0002] With the continuous development of refrigeration technology, electronic expansion valves, due to their advantages such as high-precision control and rapid response, have gradually replaced traditional throttling devices such as capillary tubes and are widely used in various refrigeration systems. Taking refrigeration mode as an example, after the refrigerant flows through the condenser and exchanges heat with the air, it forms a high-temperature, high-pressure subcooled liquid refrigerant. This subcooled liquid then passes through the electronic expansion valve. The sudden reduction in the flow area of ​​the electronic expansion valve causes a sharp drop in the pressure of the high-temperature, high-pressure liquid refrigerant flowing through the valve body, accompanied by a phase transition. However, because the flow pattern and pressure changes of the refrigerant during this process are extremely drastic, and the phase transition is also highly unstable, these factors are all significant contributors to flow-induced noise. This inevitably leads to varying degrees of noise generated when the refrigerant flows through the electronic expansion valve, negatively impacting product promotion and user experience.

[0003] Currently, common noise reduction technologies for electronic expansion valves mainly include using damping blocks, refrigerant fluid bypass, optimizing the piping before and after the valve, and adding noise-reducing components inside the electronic expansion valve. However, these existing methods suffer from poor noise reduction effects and relatively high manufacturing requirements. Utility Model Content

[0004] Therefore, this utility model provides an electronic expansion valve and an air conditioner that can overcome the technical problems in related technologies, such as poor noise reduction effect and relatively high manufacturing requirements for the noise reduction design of electronic expansion valves.

[0005] To address the aforementioned problems, this utility model provides an electronic expansion valve, comprising a valve body and a valve needle located within the valve body. The valve body has an inlet channel and an outlet channel, which are connected via a valve orifice. The valve needle can adjust the opening of the valve orifice. The diameter of the valve orifice is Dc, and the height of the valve orifice in the axial direction of the valve needle is Hc, where 0.25 < Hc / Dc < 1.5.

[0006] In some implementations, 1.0 mm ≤ Dc ≤ 10.0 mm, and / or 0.1 mm ≤ Hc ≤ 3.0 mm.

[0007] In some embodiments, the area where the inlet channel connects with the valve orifice is the upstream cavity, the diameter of the upstream cavity is D1, and the area where the outlet channel connects with the valve orifice is the downstream cavity, the diameter of the downstream cavity is D2, 2.9≤D1 / Dc≤5.0, and / or, 2.9≤D2 / Dc≤5.0.

[0008] In some embodiments, both the upstream cavity and the downstream cavity are conical structures with the cone angle close to the valve hole. The cone angle of the upstream cavity is α1, and the cone angle of the downstream cavity is α2, where 159.4°≤α1<180° and 120°≤α2<180°.

[0009] In some implementations, α1 = 160°, α2 = 160°.

[0010] In some embodiments, a filter screen is provided in the outflow channel, and the porosity of the filter screen is ε, where 0.3≤ε≤0.6.

[0011] In some embodiments, ε = 0.38; and / or, the mesh diameter l, wire diameter d, and porosity ε of the filter screen satisfy the following formula:

[0012]

[0013] In some implementations, 0.1mm ≤ d ≤ 0.3mm, and 0.15mm ≤ l ≤ 1.0mm.

[0014] In some embodiments, at least two layers of the filter screen are provided in the outflow channel; and / or, the mesh size of the filter screen is N, where 20 mesh ≤ N ≤ 100 mesh.

[0015] In some embodiments, the minimum distance between the filter screen closest to the valve hole and the valve hole is L1, 1.0mm≤L1≤3.0mm; and / or, the distance between two adjacent filter screens is L2, 0.5mm≤L2≤2.0mm.

[0016] This utility model also provides an air conditioner, including the above-mentioned electronic expansion valve.

[0017] The electronic expansion valve and air conditioner provided by this utility model have the following beneficial effects:

[0018] By limiting the ratio of valve orifice height Hc to valve orifice diameter Dc, the noise level of the designed electronic expansion valve can be kept low. The external dimensions of the electronic expansion valve body need little or no modification, and the manufacturing requirements are relatively low.

[0019] When Dc is in the range of 1mm to 10mm, the refrigerant flows through the valve body to achieve throttling, which not only ensures the throttling capacity but also makes the flow field smoother, which can further reduce flow-induced noise.

[0020] The size range of D1 and D2 relative to the valve orifice Dc has been limited and optimized to prevent them from being too large or too small, which would cause a sudden expansion / contraction structure at the connection with the corresponding inlet and outlet channels, resulting in excessive flow-induced noise. In addition, it also prevents the cavity formed in the connection area from being too small, which would cause uneven mixing of the fluid in the electronic expansion valve before and after flowing through the center of the valve body, increasing the possibility of noise generation.

[0021] Setting up a filter can effectively reduce noise by uniformizing the flow rate, breaking up air bubbles, and reducing eddies. Attached Figure Description

[0022] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0023] Figure 1 This is a partial structural diagram of the internal structure of the electronic expansion valve in this utility model;

[0024] Figure 2 yes Figure 1 A diagram showing the dimensional parameters of a local structure of the electronic expansion valve in the diagram;

[0025] Figure 3 This is the noise simulation result of the electronic expansion valve of this utility model with different valve orifice heights (when Dc = 2.0 mm);

[0026] Figure 4 This is the noise simulation result of the cone angle of different upstream cavities in the electronic expansion valve of this utility model;

[0027] Figure 5 This is the noise simulation result of the cone angle of different downstream cavities in the electronic expansion valve of this utility model;

[0028] Figure 6 This is a comparison chart of noise simulation results between the electronic expansion valve of this utility model with a filter screen and the prior art without a filter screen.

[0029] Figure 7 This is a cloud diagram showing the influence of different valve orifice heights Hc (Hc = 0.5 mm in a, Hc = 1.3 mm in b, and Hc = 3.0 mm in c) on turbulent kinetic energy in this utility model.

[0030] Figure 8 This is a simulation cloud map of turbulent kinetic energy of the double-layer filter screen at a spacing of 2 mm (a) and 0.5 mm (b) in another embodiment of the present invention.

[0031] The attached figures are labeled as follows:

[0032] 1. Valve body; 11. Inlet channel; 12. Outlet channel; 13. Valve hole; 2. Valve needle; 21. Valve needle seat; 3. Filter screen. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0034] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0035] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90° or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0036] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0037] See Figures 1 to 8 As shown, according to an embodiment of the present invention, an electronic expansion valve is provided, including a valve body 1 and a valve needle 2 located within the valve body 1. The valve body 1 has an inlet channel 11 and an outlet channel 12, which are connected via a valve hole 13. The valve needle 2 can adjust the opening degree of the valve hole 13. Specifically... Figure 1 As shown for reference, in a specific embodiment, the fluid flow directions of the aforementioned inlet channel 11 and outlet channel 12 are approximately perpendicular, thus forming an L-shape between the two channels. The corresponding appearance of the valve body 1 is also approximately L-shaped. The aforementioned valve orifice 13 is specifically formed at the inlet position of the outlet channel 12. The valve needle 2 is disposed on the valve needle seat 21, which is connected to the valve body 1. By controlling the linear displacement of the valve needle 2, the relative position between the valve needle 2 and the valve orifice 13 is adjusted, that is, the opening degree of the valve orifice 13 is adjusted. During normal operation of the electronic expansion valve, the refrigerant enters the outlet channel 12 through the valve orifice 13 from the inlet channel 11 and flows out. In the area (annular flow gap) formed after the valve needle 2 and the valve orifice 13 are combined, the refrigerant state changes due to the sudden change in the flow area, achieving the purpose of throttling. The diameter of the valve orifice 13 is Dc, and the height of the valve orifice 13 in the axial direction of the valve needle 2 is Hc, where 0.25 < Hc / Dc < 1.5.

[0038] In this technical solution, by limiting the ratio of valve hole height Hc to valve hole diameter Dc of valve hole 13, the noise of the designed electronic expansion valve can be guaranteed to be at a low level. The external dimensions of the valve body 1 of the electronic expansion valve need to be modified little or even not modified, and the manufacturing requirements are relatively low.

[0039] To further improve the noise reduction effect on the electronic expansion valve, experiments have verified that when 1.0mm≤Dc≤10.0mm, especially when 2.0mm≤Dc≤8.0mm, the noise reduction effect is better when Hc / Dc is between 0.2 and 1.0. It is worth emphasizing that when Dc is within the aforementioned range, the refrigerant flow through the valve body achieves throttling while maintaining throttling capability, resulting in smoother flow and further reducing flow-induced noise.

[0040] To further reduce noise levels and improve noise reduction performance, the preferred values ​​are 0.1mm ≤ Hc ≤ 3.0mm, and preferably 0.5mm ≤ Hc ≤ 2.0mm. (See [reference needed]). Figure 3 As shown in the figure, the simulation results for noise are presented when Dc = 2.0 mm and Hc is 0.5 mm, 1.3 mm, and 3.0 mm, respectively. The results show that a valve orifice height of 1.3 mm performs best under the above comparison conditions; therefore, Hc is preferably 1.3 mm. Additionally, it should be noted that... (See also...) Figure 7As shown in the figure, the trend of the effect of valve orifice height Hc on noise is illustrated. Figure 7 As can be seen, the turbulent kinetic energy develops faster behind valve orifice 13 (i.e., downstream side) over a wide range, and the total value of turbulent kinetic energy is large, which is the main factor in noise formation. When Hc = 1.3 mm, the turbulent kinetic energy is the smallest, and the noise caused by it is also relatively smaller. Therefore, the operating noise of the electronic expansion valve is also correspondingly smaller.

[0041] In some embodiments, the area where the inlet channel 11 connects with the valve orifice 13 is the upstream cavity, and the diameter of the upstream cavity is D1. The area where the outlet channel 12 connects with the valve orifice 13 is the downstream cavity. Based on the diameter of the electronic expansion valve (i.e., the flow range of the electronic expansion valve), in order to ensure that the refrigerant fluid flowing through the electronic expansion valve can be fully mixed in the upstream and downstream cavities and to avoid flow-induced noise caused by uneven local flow, the diameter of the downstream cavity is D2, 2.9≤D1 / Dc≤5.0, and / or 2.9≤D2 / Dc≤5.0.

[0042] In this technical solution, the size range of D1 and D2 relative to the valve orifice Dc is limited and optimized to prevent them from being too large or too small, which would cause a sudden expansion / contraction structure at the connection with the corresponding inlet channel 11 and outlet channel 12, resulting in excessive flow-induced noise. In addition, it also prevents the cavity formed in the connection area from being too small, which would cause uneven mixing of the fluid in the electronic expansion valve before and after flowing through the center of the valve body, increasing the possibility of noise generation.

[0043] In some embodiments, both the upstream and downstream cavities are conical structures with their cone angles closer to the valve orifice 13. The cone angle of the upstream cavity is α1, and the cone angle of the downstream cavity is α2, where 159.4° ≤ α1 < 180° and 120° ≤ α2 < 180°. In a preferred embodiment, α1 = 160° and α2 = 160°, which can further reduce the flow-induced noise of the electronic expansion valve. See details. Figure 4 and Figure 5 The simulation results of noise under different cone angles upstream and downstream are shown. The simulation results show that the total noise value and peak value are both less when the cone angle of the upstream is 159.4° than when it is 126.9°; similarly, the total noise value is the smallest when the cone angle of the downstream is 160°.

[0044] In some embodiments, a filter screen 3 is provided in the outflow channel 12. The refrigerant after throttling has an extremely unstable flow state and uneven two-phase distribution. After setting the filter screen 3 of this utility model, it can effectively achieve positive noise reduction effects such as uniform flow rate, dispersing air bubbles and reducing eddies. The porosity of the filter screen 3 is ε. Taking into account the reduction of the flow area of ​​the filter screen 3 and the increase of the wetted perimeter, it is limited to 0.3≤ε≤0.6, preferably ε=0.38.

[0045] To simplify the selection of filter screen 3, the mesh count of filter screen 3 is N (unit: mesh), and the mesh diameter l (unit: mm), wire diameter d (unit: mm), and porosity ε of filter screen 3 satisfy the following formula:

[0046]

[0047] In some implementations, 0.1mm≤d≤0.3mm, 0.15mm≤l≤1.0mm, 20 mesh≤N≤100 mesh, and in one specific embodiment, N=70 mesh.

[0048] In some embodiments, at least two layers of the filter screen 3 are disposed within the outflow channel 12, with the two layers of filter screen 3 arranged in parallel and spaced apart within the outflow channel 12. This can further reduce the total noise value (characterized by the coverage area) and peak noise, resulting in a significant noise reduction effect. For details, please refer to [link to relevant documentation]. Figure 6 As shown.

[0049] In some embodiments, the minimum distance between the filter screen 3, which is closest to the valve hole 13, and the valve hole 13 is L1, where 1.0mm≤L1≤3.0mm, preferably L1=1.5mm, to prevent the filter screen 3 from being installed too close to the valve hole 13. Since the flow velocity at the outlet of the valve hole 13 is relatively fast, installing the filter screen 3 too close will lead to increased turbulent kinetic energy and increased noise from the high-speed fluid impacting the filter screen.

[0050] When the filter screen 3 is arranged in at least two layers, the distance between two adjacent layers of the filter screen 3 is L2, 0.5mm≤L2≤2.0mm, preferably L2=1.0mm.

[0051] According to an embodiment of the present invention, an air conditioner is also provided, including the above-described electronic expansion valve.

[0052] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0053] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model. The above description is only a preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. An electronic expansion valve, comprising a valve body (1) and a valve needle (2) located within the valve body (1), wherein the valve body (1) has an inlet channel (11) and an outlet channel (12) configured therein, the inlet channel (11) and the outlet channel (12) being connected through a valve orifice (13), and the valve needle (2) being capable of adjusting the opening degree of the valve orifice (13), characterized in that, The diameter of the valve hole (13) is Dc, and the height of the valve hole (13) in the axial direction of the valve needle (2) is Hc, where 0.25 < Hc / Dc < 1.

5.

2. The electronic expansion valve according to claim 1, characterized in that, 1.0mm≤Dc≤10.0mm, and / or, 0.1mm≤Hc≤3.0mm.

3. The electronic expansion valve according to claim 1, characterized in that, The area where the inlet channel (11) connects with the valve hole (13) is the upstream cavity, and the diameter of the upstream cavity is D1. The area where the outlet channel (12) connects with the valve hole (13) is the downstream cavity, and the diameter of the downstream cavity is D2. 2.9≤D1 / Dc≤5.0, and / or 2.9≤D2 / Dc≤5.

0.

4. The electronic expansion valve according to claim 3, characterized in that, Both the upstream cavity and the downstream cavity are cone structures with the cone angle close to the valve hole (13). The cone angle of the upstream cavity is α1, and the cone angle of the downstream cavity is α2. 159.4°≤α1<180°, 120°≤α2<180°.

5. The electronic expansion valve according to claim 4, characterized in that, α1＝160°，α2＝160°。 6. The electronic expansion valve according to claim 1, characterized in that, The outflow channel (12) is provided with a filter screen (3), and the porosity of the filter screen (3) is ε, 0.3≤ε≤0.

6.

7. The electronic expansion valve according to claim 6, characterized in that, ε = 0.38; and / or, the mesh diameter l and wire diameter d of the filter screen (3) satisfy the following formula with respect to the porosity ε:

8. The electronic expansion valve according to claim 7, characterized in that, 0.1mm≤d≤0.3mm, 0.15mm≤l≤1.0mm.

9. The electronic expansion valve according to claim 6, characterized in that, At least two layers of the filter screen (3) are provided in the outflow channel (12); and / or, the mesh number of the filter screen (3) is N, where 20 mesh ≤ N ≤ 100 mesh.

10. The electronic expansion valve according to claim 9, characterized in that, The minimum distance between the filter screen (3) closest to the valve hole (13) and the valve hole (13) is L1, 1.0mm≤L1≤3.0mm; and / or, the distance between two adjacent filter screens (3) is L2, 0.5mm≤L2≤2.0mm.

11. An air conditioner, characterized in that, Includes the electronic expansion valve according to any one of claims 1 to 10.

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