Electronic expansion valve and refrigeration equipment

Abstract

The utility model discloses an electronic expansion valve and refrigeration equipment, and relates to the technical field of electronic expansion valves, a first connecting pipe or a second connecting pipe of the electronic expansion valve is internally provided with an annular external member, the annular external member comprises an annular base and a shaft neck part which is coaxially arranged with the annular base, and an annular gap is formed between the outer side of the shaft neck part and the inner wall of the pipe; the annular sleeve piece is axially provided with a flow guide channel, the flow guide channel penetrates through the annular base and the shaft neck part, and the shaft neck part is provided with a bypass hole communicating the flow guide channel and the annular gap; the silencing block is arranged in the flow guide channel and comprises at least one silencing net communicating with the flow guide channel. According to the technical scheme, flow adjusting requirements under different working conditions are met through the annular gap and the bypass hole, even if the noise reduction net is blocked by impurities, normal throttling of the electronic expansion valve is not affected, the valve body cannot be blocked, and the normal throttling function of the electronic valve is maintained.

Description

Technical Field

[0001] This utility model relates to the field of electronic expansion valve technology, and in particular to an electronic expansion valve and a refrigeration device. Background Technology

[0002] The electronic expansion valves used in current air conditioning systems are prone to generating flow noise during refrigerant throttling, a problem that is particularly prominent when the indoor unit is running. High-frequency refrigerant noise not only disrupts the quietness of the environment but also directly affects the user experience.

[0003] Current industry solutions primarily focus on valve body structure optimization, including improving valve port shape and adjusting valve cavity geometry. The noise suppression effectiveness of these solutions is strongly correlated with the operating conditions of the refrigeration system. When system pressure, flow rate, and other parameters change, the noise reduction efficiency fluctuates significantly, making it difficult for these solutions to adapt to different refrigeration systems. Utility Model Content

[0004] The main purpose of this invention is to propose an electronic expansion valve and refrigeration equipment, which is designed to be installed on the connecting pipe through a modular sound-absorbing structure, so as to be applicable to different systems without changing the structure of the expansion valve body, and to achieve cross-system adaptability and flow noise suppression.

[0005] To achieve the above objectives, the electronic expansion valve proposed in this utility model includes:

[0006] The valve body has a valve cavity;

[0007] A first connecting pipe is disposed on the periphery of the valve body and connects to the valve cavity;

[0008] The second connecting pipe is located at the bottom of the valve body and connects to the valve cavity;

[0009] An annular assembly includes an annular base and a journal coaxially disposed with the annular base. The annular base is disposed on the inner wall of the first connecting pipe or the second connecting pipe. The outer diameter of the journal is smaller than the outer diameter of the annular base. An annular gap exists between the outer side of the journal and the inner wall of the pipe. The annular assembly is axially provided with a flow guide channel that passes through the annular base and the journal. The journal is provided with a bypass hole that connects the flow guide channel and the annular gap.

[0010] A noise-absorbing block is disposed within the flow channel, and the noise-absorbing block includes at least one noise-absorbing mesh that communicates with the flow channel.

[0011] In one embodiment, the cross-sectional area of ​​the silencing mesh is greater than the total cross-sectional area of ​​the bypass holes.

[0012] In one embodiment, the ratio of the cross-sectional area of ​​the bypass hole to that of the valve port is in the range of 1-1.5.

[0013] In one embodiment, the ratio of the minimum cross-sectional area of ​​the annular gap to the cross-sectional area of ​​the valve port is in the range of 1-1.5.

[0014] In one embodiment, a plurality of bypass holes are provided at circumferential intervals along the journal.

[0015] In one embodiment, the flow channel extends through the annular base and the journal.

[0016] In one embodiment, the valve body has a valve port communicating with the valve cavity, and the bypass hole is closer to the valve port than the muffler block.

[0017] In one embodiment, the end of the journal shaft away from the annular base is provided with a mounting groove with an inner diameter larger than the inner diameter of the flow channel, and the noise-reducing block is installed in the mounting groove.

[0018] In one embodiment, the journal shaft is further provided with a tapered opening that gradually widens in the direction away from the muffler block, and the tapered opening communicates with the mounting groove.

[0019] In one embodiment, the annular base and the journal are integrally machined.

[0020] In one embodiment, the inner wall of the first connecting pipe or the second connecting pipe is provided with an abutment protrusion that abuts against the annular base in the direction away from the valve cavity.

[0021] In one embodiment, two abutment protrusions are spaced apart, and the two abutment protrusions define a groove for mounting the annular base.

[0022] In one embodiment, the annular base is disposed on the second connecting pipe, and the minimum distance between the surface of the silencing block 22 near the valve body and the valve port of the valve body communicating with the second connecting pipe is H, where H≤20mm.

[0023] In one embodiment, the height of the annular base is H. a The minimum distance from the center of the bypass hole to the valve port is H. b Satisfying 3mm≤H a <H b ≤10mm.

[0024] This utility model also proposes a refrigeration device, including an electronic expansion valve as described in any of the preceding claims.

[0025] This invention's technical solution uses an annular base mounted on the inner wall of the connecting pipe, eliminating the need to alter the expansion valve's body structure. By using a journal diameter smaller than the annular base's outer diameter, a gap is formed on the inner wall of the connecting pipe. This annular gap and bypass hole adapt to different flow regulation requirements under various operating conditions, solving the problem of high-frequency noise generated by turbulence and cavitation at the throttling valve orifice in traditional electronic expansion valves due to sudden increases in flow velocity and pressure changes. The different operating conditions refer to: under small opening conditions, the refrigerant can flow back from the bypass hole to the guide channel, allowing the refrigerant at the manifold orifice to pass through the silencer block, thus improving noise reduction. When fully open or at a large opening (at least halfway open), the refrigerant flowing out of the valve cavity mainly flows out through the valve port and passes through the flow guide channel and the muffler block for noise reduction. Furthermore, regardless of whether it is a small opening or a fully open or large opening, when impurities in the refrigerant cause the muffler block to become blocked, the bypass hole can provide an auxiliary flow path for the refrigerant. This can effectively prevent the valve body from being completely blocked due to filter clogging, ensuring the continuous operation of the system. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 A schematic diagram of an embodiment of the electronic expansion valve provided by this utility model;

[0028] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0029] Figure 3 Line graph showing the ratio of the cross-sectional area of ​​the bypass orifice and the valve port to the corresponding noise value;

[0030] Figure 4 A line graph showing the ratio of the cross-sectional area of ​​the annular gap and the valve port to the corresponding noise value;

[0031] Figure 5 A line graph showing the noise values ​​corresponding to different distances H;

[0032] Figure 6 The CFD simulation diagram shows the fluid velocity distribution of the electronic expansion valve.

[0033] Figure 7 For different sizes of H b Line graph of the corresponding noise values.

[0034] Explanation of icon numbers:

[0035] 1A, First connecting pipe;

[0036] 1B. Second connecting pipe;

[0037] c. Annular gap;

[0038] d1, Abutting the protrusion;

[0039] d2, groove;

[0040] 10. Valve body; 10a. Connecting part; 11. Valve cavity; 12. Valve port; 12. Straight edge section; 12b. Conical flared section;

[0041] 20. Noise-absorbing structure; 21. Annular assembly; 21a. Annular base; 21b. Journal neck; 211. Flow channel; 212. Bypass hole; 213. Mounting groove; 214. Tapered opening;

[0042] 22. Silencing block; 221. Silencing mesh.

[0043] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0044] 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. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0045] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0046] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0047] The electronic expansion valves used in current air conditioning systems are prone to generating flow noise during refrigerant throttling, a problem particularly pronounced during indoor unit operation. High-frequency refrigerant noise not only disrupts environmental quietness but also directly impacts the user experience. Existing industry solutions primarily focus on valve body structure optimization, including improving valve port morphology and adjusting valve cavity geometry. However, the noise suppression effectiveness of these solutions is strongly correlated with the operating conditions of the refrigeration system. When system pressure, flow rate, and other parameters change, the noise reduction efficiency fluctuates significantly, making it difficult for these solutions to adapt to different refrigeration system specifications.

[0048] This invention proposes a noise reduction structure for use in the connecting pipe of an electronic expansion valve. The aim is to install a modular noise reduction structure on the connecting pipe, so as to be applicable to different systems without changing the structure of the expansion valve body, thereby achieving cross-system adaptability and flow noise suppression.

[0049] Please see Figure 1 and Figure 2 In one embodiment of the present invention, the noise reduction structure 20 is used as a connecting pipe for an electronic expansion valve. The electronic expansion valve includes a valve body 10 having a valve cavity 11, a first connecting pipe 1A, and a second connecting pipe 1B. The first connecting pipe 1A is disposed on the periphery of the valve body 10 and communicates with the valve cavity 11. The second connecting pipe 1B is disposed at the bottom of the valve body 10 and communicates with the valve cavity 11.

[0050] In one embodiment, the noise reduction structure 20 is disposed in the first connecting pipe 1A.

[0051] In one embodiment, the noise reduction structure 20 is disposed in the second connecting pipe 1B.

[0052] Specifically, the noise reduction structure 20 includes an annular assembly 21 and a noise reduction block 22. The annular assembly 21 includes an annular base 21a for mounting on the inner wall of the connecting pipe and a journal 21b coaxially disposed with the annular base 21a. The outer diameter of the journal 21b is smaller than the outer diameter of the annular base 21a. The annular assembly 21 is axially provided with a flow channel 211, which passes through the annular base 21a and the journal 21b. The journal 21b is provided with a bypass hole 212 communicating with the flow channel 211. The noise reduction block 22 is disposed in the flow channel 211. The noise reduction block 22 includes at least one noise reduction mesh 221 communicating with the flow channel 211. In the flow direction of the fluid through the flow channel 211, the bypass hole 212 is located upstream of the noise reduction block 22. There is an annular gap c between the outer side and the inner wall of the journal 21b.

[0053] In this embodiment, the flow channel 211 passes through the annular base 21a and the journal 21b; in other embodiments, the silencing mesh 221 may be arranged on the annular assembly 21, that is, the silencing block 22 and the annular assembly 21 are configured as one unit.

[0054] In this embodiment, the bypass hole 212 is closer to the valve port 12 than the muffler block 22; the annular base 21a is closer to the valve port 12, and the journal 21b is away from the annular base 21a. In other embodiments, the annular assembly 21 is installed upside down, that is, the annular base 21a is away from the valve port, the muffler block 22 is close to the valve port 12, and the annular gap c connects to the valve port 12.

[0055] The following description uses the example of the annular assembly 21 being installed in the second connecting pipe 1B, where the bypass hole 212 is closer to the valve port 12 than the silencer block 22.

[0056] When the electronic expansion valve is at a small opening, the flow velocity through valve port 12 is relatively high, and the bypass hole 212 is closer to valve port 12. Under the action of negative pressure difference, the refrigerant is more likely to flow back from downstream through the annular gap c and through the bypass hole 212, and then merge with the central jet of valve port 12. This allows more refrigerant to flow through the muffler block 22 to reduce noise and improve the noise reduction effect. Furthermore, because of the existence of the bypass hole 212, even if the muffler mesh 221 is blocked by impurities, it can still flow out through the bypass hole 212 to the annular gap c without affecting the normal throttling of the electronic expansion valve, preventing the valve body 10 from becoming blocked, and maintaining the normal throttling function of the electronic valve.

[0057] When the electronic expansion valve is fully open or at a large opening, the refrigerant is throttled and mainly flows out through the guide channel 211 and the silencer block 22. In the silencer mesh 221 of the silencer block 22 (such as honeycomb or porous structure), it is divided into thin streams, the flow velocity is reduced and the flow direction is constrained, reducing turbulent collision and vibration noise.

[0058] In addition, because of the existence of the bypass hole 212, even if the silencing mesh 221 is blocked by impurities, it can still flow out to the annular gap c through the bypass hole 212 without affecting the normal throttling of the electronic expansion valve, and will not cause the valve body 10 to be blocked, thus maintaining the normal throttling function of the electronic valve.

[0059] The technical solution of this utility model, by using an annular base 21a installed on the inner wall of the connecting pipe, solves the problem that related solutions, which reduce noise by changing the design of the valve port or the structure of the valve cavity 11, often fail to achieve a consistently effective noise reduction effect when dealing with different types of refrigeration systems, without changing the structure of the expansion valve body. Because the outer diameter of the journal 21b is smaller than the outer diameter of the annular base 21a, an annular gap c can be formed with the inner wall of the connecting pipe. Since the silencing block 22 has a silencing mesh 221, if there are air bubbles in the refrigerant after passing through the silencing block 22, they will be refined into smaller bubbles, preventing large bubbles from bursting and generating noise. Sound energy is absorbed and weakened, reducing the noise level. At the same time, because of the existence of the bypass hole 212, even if the silencing mesh 221 is blocked by impurities, it will not affect the normal throttling of the electronic expansion valve, and will not cause the valve body 10 to become blocked, maintaining the normal throttling function of the electronic valve.

[0060] The electronic expansion valve includes a nut and a lead screw. The nut is sealed to the valve body 10 and is located on the top of the valve body 10. The lead screw is threadedly engaged with the nut. The valve body 10 is also fitted with a housing, which covers the lead screw and nut. The lead screw passes through the nut and is fixed to a limiting plate at the end away from the nut. The limiting plate is connected to a rotor. A coil assembly can be fitted outside the housing. Under the electromagnetic action of the coil assembly, the lead screw is driven to rotate circumferentially through the rotor and the limiting plate. The end of the lead screw away from the limiting plate is connected to the valve needle. Because the nut is fixed to the valve body 10, the valve needle moves up and down axially with the lead screw, thereby adjusting the opening degree of the flow channel formed between the opening and the valve port 12.

[0061] There are various ways to connect the valve needle and the lead screw. In this embodiment, in order to prevent the valve needle from rotating with the lead screw, the valve needle and the lead screw are connected by a bearing. The end of the lead screw is fixed by a locking member. The locking member abuts against the bearing to drive the valve needle to move up and down, and does not rotate with the lead screw in the circumferential direction.

[0062] In addition, a compression spring is provided between the lead screw and the bearing. The compression spring stores elastic force when the valve needle moves upward in the axial direction and releases it when the valve needle moves downward in the axial direction, so that the valve needle can also have a certain adjustment capability when sealing the valve port 12.

[0063] In other embodiments, the valve needle and the lead screw are engaged by a threaded structure; or the valve needle and the lead screw are elastically connected by a spring; or the valve needle and lead screw assembly can be connected as a whole by welding or interference fitting.

[0064] There are various ways to connect the valve needle and the lead screw. The specific method to choose depends on the valve's design requirements, the operating environment, and operational needs.

[0065] Please see Figure 1 and Figure 2 Specifically, the valve body 10 has a connecting portion 10a, which protrudes from the valve port 12 along the valve body 10 to facilitate the connection of an external connecting pipe. It is understood that, in order not to affect the outflow of the cooling medium in the bypass hole 212, the journal 21b has a gap with the inner wall of the connecting pipe to avoid covering the bypass hole 212.

[0066] Furthermore, the ratio of the cross-sectional area of ​​the bypass hole 212 to the cross-sectional area of ​​the valve port 12 ranges from 1 to 1.5. The cross-sectional area is the flow channel cross-sectional area of ​​the hole. The reason why the total cross-sectional area of ​​the bypass hole 212 is greater than or equal to the cross-sectional area of ​​the valve port 12 is to ensure that the flow capacity in the fully open state is not affected. The reason why it is less than or equal to 1.5 times is that if the cross-sectional area of ​​the bypass hole 212 is too large, a lot of refrigerant will flow away from the bypass hole 212 without sufficient noise reduction by the silencer block 32, thus weakening the noise reduction effect.

[0067] Specifically, multiple bypass holes 212 are provided at circumferential intervals along the journal 21b.

[0068] Multiple bypass holes 212 ensure that the refrigerant can find an unobstructed outlet under any circumstances. Understandably, the size of each bypass hole 212 can be adjusted to meet specific needs, ensuring that under normal operating conditions, the refrigerant is primarily refined through the silencer block 22. However, in the event of filter clogging, the multiple bypass holes 212 provide multiple backup flow paths, ensuring that the refrigerant can continue to flow and maintain normal system operation.

[0069] Multiple bypass holes 212 are evenly distributed on the sidewall of the journal 21b. The bypass holes 212 can be arranged at equal intervals along the circumference of the journal 21b, or their distribution can be optimized according to the direction and velocity of the refrigerant flow to ensure that the refrigerant can flow out from a single unobstructed outlet regardless of its direction of inflow. This improves the uniformity of refrigerant flow and reduces the possibility of localized pressure buildup. Furthermore, the number of bypass holes 212 can be adjusted according to the operating conditions required in actual applications, such as increasing the number of bypass holes 212 to improve safety or reducing the number to simplify the structure.

[0070] Specifically, the number and size of the bypass holes 212 can be adjusted according to actual needs to adapt to different operating conditions. Under normal circumstances, the total cross-sectional area of ​​the bypass holes 212 is greater than or equal to the cross-sectional area of ​​the valve port 12, and the cross-sectional area of ​​a single bypass hole 212 is smaller than that of the valve port 12, so as to ensure that under normal operating conditions, the refrigerant is mainly refined through the silencer block 22.

[0071] In other words, under small opening conditions, the refrigerant can flow back from the bypass hole 212 to the guide channel 211, allowing the refrigerant at the manifold 12 to pass through the silencer block 22, thus improving the noise reduction effect. When fully open or at a large opening (at least halfway open of the valve port 12), the refrigerant flowing out of the valve chamber 11 mainly flows out through the valve port 12 and passes through the guide channel 211 and the silencer block 22 for noise reduction. Furthermore, regardless of whether it is a small opening or a fully open or large opening condition, if impurities in the refrigerant cause the silencer block 22 to become blocked, the bypass hole 212 can still provide an auxiliary flow path for the refrigerant. This effectively avoids the complete blockage of the valve body 10 due to filter clogging, ensuring continuous system operation.

[0072] Similarly, the flow cross-sectional area of ​​the silencing mesh 221 is larger than the flow cross-sectional area of ​​the total bypass hole 212.

[0073] It should be noted that the cross-sectional area, also known as the flow cross-sectional area, refers to the actual flow area of ​​the fluid when it passes through the orifice. This is different from the nominal cross-sectional area of ​​the orifice because the actual fluid flow is affected by the viscosity effect, which causes the flow stream to contract, thus forming the minimum flow cross-sectional area. In other words, the flow cross-sectional area is the effective flow area of ​​the fluid when it passes through the orifice.

[0074] The table below shows the ratio of the cross-sectional area of ​​the bypass orifice to that of the valve port and the corresponding noise values.

[0075] Bypass port / valve port 1 1.2 1.5 1.7 1.9 2.1 Noise level in dB(A) 40.20 40.18 40.19 41.04 41.87 42.88

[0076] Based on the content of the table above and in combination Figure 3 The noise levels show that when the ratio of the cross-sectional area of ​​the bypass hole 212 to that of the valve port 12 is greater than 1.5, the noise reduction effect weakens and the noise increases. Therefore, if low-noise operation is required, the ratio of the bypass hole to the valve port should be controlled within the range of ≤1.5.

[0077] Furthermore, the ratio of the cross-sectional area of ​​the annular gap c to the cross-sectional area of ​​the valve port 12 ranges from 1 to 1.5. The reason why the minimum cross-sectional area of ​​the annular gap c is greater than or equal to the cross-sectional area of ​​the valve port 12 is to ensure that the flow capacity in the fully open state is not affected. The reason why it is less than or equal to 1.5 times is that if the cross-sectional area of ​​the annular gap c is too large, it will occupy the space of the silencing block 32, resulting in a smaller cross-sectional area of ​​the silencing block 32. That is, the volume of the silencing block 32 used to refine bubbles and absorb sound energy will decrease, and the silencing effect will be worse.

[0078] The table below shows the ratio of the annular gap c to the cross-sectional area of ​​the valve port 12 and the corresponding noise values.

[0079] Annular gap / valve port 1 1.2 1.5 1.7 1.9 2.1 Noise level in dB(A) 39.89 40.06 40.01 41.01 41.92 42.95

[0080] Based on the content of the table above and in combination Figure 4The noise levels show that when the ratio of the annular gap c to the cross-sectional area of ​​valve port 12 is greater than 1.5, the silencing effect weakens and the noise increases. Therefore, for low-noise operation, the ratio of the annular gap c to valve port 12 should be controlled within the range of ≤1.5. By precisely controlling the refrigerant flow rate and pressure release rate of the bypass diversion, noise can be suppressed while avoiding excessive diversion that leads to a decrease in throttling efficiency.

[0081] The silencing block 22 is a multi-layer filter stack, and the multiple silencing meshes 221 are multiple meshes set on the silencing block 22, which can refine the bubbles in the refrigerant into smaller bubble groups, thereby reducing the high-frequency noise generated by bubble rupture.

[0082] The cross-sectional shape of the mesh can be circular, rectangular, or irregular (such as spiral or honeycomb), and the diameter can be set to be smaller than the size of common large air bubbles in refrigerant to ensure that air bubbles are forcibly broken into tiny air bubbles as they pass through.

[0083] Understandably, when the refrigerant flows through valve port 12 into flow channel 211, air bubbles enter the mesh of silencer block 22 along with the refrigerant. Due to the narrow channel and surface tension, large bubbles are broken down into smaller bubbles (e.g., diameter reduced from 5 mm to 0.5 mm). The energy released when these tiny bubbles burst is significantly reduced, thereby reducing high-frequency noise. Furthermore, the multiple meshes disperse the refrigerant flow rate, preventing turbulent noise generated by localized high-speed flow.

[0084] Compared to existing technologies that rely solely on optimizing the shape of the valve port 12 or valve cavity 11, this invention offers greater specificity and noise reduction. Furthermore, the parameters of the silencer block 22 can be flexibly adjusted according to the refrigerant flow and pressure range of different refrigeration systems, making it suitable for various application scenarios and easy to install and maintain.

[0085] This invention incorporates a silencing structure 20 in either the first connecting pipe 1A or the second connecting pipe 1B. Embedding the silencing structure 20 within the connecting pipe instead of the valve body 10 avoids the limitations of traditional valve body 10 structure optimization and enhances the versatility of the noise reduction solution. The silencing structure 20, through multiple mesh openings on the silencing block 22 connected to the flow guide channel 211, allows air bubbles to enter the flow guide channel 211 along with the refrigerant via the valve port 12. This process refines large air bubbles into smaller ones and smooths the refrigerant flow, enabling the electronic valve to reduce refrigerant flow noise while maintaining flow control accuracy. This is particularly suitable for environments sensitive to environmental noise, such as air conditioning systems. Furthermore, when impurities are present in the refrigerant or the filter is clogged, the bypass hole 212 provides an auxiliary flow path for the refrigerant, effectively preventing complete blockage of the valve body 10 due to filter clogging and ensuring continuous system operation.

[0086] Specifically, the end of the journal 21b away from the annular base 21a is provided with a mounting groove 213 with an inner diameter larger than the inner diameter of the guide channel 211, and the noise reduction block 22 is installed in the mounting groove 213.

[0087] An annular step is formed between the mounting groove 213 and the flow channel 211. The noise-absorbing block 22 is installed on the annular step. It can be understood that the noise-absorbing block 22 can be interference-fitted with the annular step. In order to increase its reliability, it can be fixed to the annular kit 21 by means of adhesive or riveting.

[0088] The noise reduction block 22 is installed in the mounting slot 213 so that the noise reduction block 22 can be firmly fixed in the predetermined position, avoiding the increase of complexity and cost due to the use of additional fixing devices.

[0089] Reference Figure 2 Furthermore, the journal 21b is also provided with a tapered opening 214 that gradually widens along the flow direction, and the tapered opening 214 communicates with the mounting groove 213. On the one hand, the tapered opening 214 helps to fix the muffler block 22, making it easier to accurately install the muffler block 22 into the predetermined position, and making it easier to align and fix the muffler block 22 during installation, reducing assembly errors and time. On the other hand, it makes the flow velocity of the fluid gradually decrease when it enters the mounting groove 213 from the guide channel 211.

[0090] In this embodiment, the annular base 21a and the journal 21b are integrally machined, that is, directly machined from a single piece of raw material to form an inseparable integral structure.

[0091] In other embodiments, the annular base 21a and the journal 21b are assembled by welding, bonding or other means.

[0092] To facilitate the fixing of the noise reduction structure 20 to the connecting pipe, taking the fixing of the noise reduction structure 20 to the inner wall of the second connecting pipe 1B as an example, the inner wall of the second connecting pipe 1B is provided with a groove d2, and the annular base 21a is provided in the groove d2.

[0093] In one embodiment, the groove d2 is formed by an inner wall recess.

[0094] In one embodiment, the groove d2 is defined by two annular abutment protrusions d1 spaced apart on the inner wall along the flow direction. During installation, the annular fitting 21 is inserted into the second connecting pipe 1B, so that the annular base 21a is engaged in the groove d2 formed by the annular abutment protrusions d1, thus completing the fixation. Of course, it is also possible to only provide abutment protrusions d1 on the inner wall without forming a groove d2. After the annular fitting 21 is inserted into the second connecting pipe 1B, the abutment protrusions d1 abut against the annular base 21a. Since the flow direction is opposite to the abutment force, it is not easy to detach.

[0095] Reference Figure 2 Specifically, the annular base 21a is provided on the second connecting pipe 1B, and the minimum distance between the surface of the silencing block 22 near the valve body 10 and the valve port 12 of the second connecting pipe 1B connected to the valve body 10 is H, where H≤20mm.

[0096] It should be noted that the valve port 12 includes a straight edge section 12 that mates with the outer wall of the valve needle 30 and a tapered flared section 12b disposed away from the valve cavity 11. The inner diameter of the valve port 12 is measured by selecting the inner diameter of the straight edge section 12. That is, the valve port 12 is a channel for the refrigerant to flow through, and the minimum inner diameter of this channel is the inner diameter of the valve port 1211.

[0097] Valve port 12 is the core noise source of sudden velocity changes and turbulence generation during refrigerant throttling. The silencing block 22 is positioned close to valve port 12 (H≤20mm) to ensure the inlet of the silencing mesh 221 is as close as possible to the noise-generating area. This allows for absorption and scattering of sound wave energy before it diffuses with the flow, achieving near-field sound energy interception and avoiding sound energy attenuation and efficiency loss due to long-distance propagation. However, if the silencing block 22 is too close to valve port 12, it may affect refrigerant flow, increase flow resistance, and reduce system efficiency. Limiting H≤20mm effectively reduces noise without significantly increasing flow resistance.

[0098] If the silencer block 22 is too far from the valve port 12 (H>20mm), the silencer block 22 cannot absorb and dissipate sound energy in time at the place with the greatest noise, and will not achieve the desired effect. The distance between the silencer block 22 and the valve port 12 is limited by the second connecting pipe 1B, and the installation space between the air conditioner indoor unit valve body 10 and the connecting pipe has a limited length.

[0099] The table below shows the H distance and the corresponding noise value range.

[0100]

[0101] Based on the content of the table above and in combination Figure 5 The noise levels show that when the distance H between the silencing block 32 and the valve port 12 is greater than 20mm, the silencing effect weakens and the noise increases. Therefore, if low-noise operation is required, H should be controlled within a range of less than 20mm.

[0102] Further integration Figure 6 The main body in the picture and Figure 1 Correspondingly, there are curved and straight pipe sections, with valve port 12 located at the bottom of the main body. Figure 6 On the left side of the screen, there is a speed and color chart. The colors, from red to dark blue, correspond to the speed values. The legend shows that the speed range is from 0 to 77.61 m / s, and the brighter the color, the higher the speed.

[0103] The highest fluid velocity occurs in certain areas, especially at the section from the opening to the straight pipe, based on experimental observations of the transparent valve body and CFD simulation calculations. Figure 6As can be seen, the core area of ​​the throttling noise is within 20mm behind valve port 12 (i.e., H≤20mm), such as Figure 6 The simulation calculation cloud diagram is shown in the figure. Figure 6 The greenish fluid is visible in part 12 of the valve port. Therefore, the entire silencing structure needs to be installed in the core area of ​​the throttling noise for the best noise reduction effect, i.e., H≤20mm.

[0104] Furthermore, the height of the annular base 21a is H. a The minimum distance from the center of the bypass hole 212 to the valve port 12 is H. b Satisfying 3mm≤H a <H b ≤10mm, H a The thickness is greater than 3mm to ensure manufacturability; if it is too small, the contact area between the annular base 21a and the second connecting pipe 1B will be too small, which is not conducive to pre-fixation during assembly. a ≤H b The purpose of keeping the bypass hole ≤10mm is to ensure that the bypass hole 212 is as close as possible to the valve port 12 while meeting process requirements. This way, when the refrigerant is ejected from the valve port 12 in a jet-like manner under small opening conditions, its velocity is very high. According to Bernoulli's equation in fluid mechanics, the higher the velocity, the lower the pressure. As the refrigerant flows downstream from the valve port 12, its velocity gradually decreases, and its pressure gradually recovers. The closer the bypass hole 212 is to the valve port 12, the lower the pressure at the bypass hole 212 relative to the downstream. Therefore, under the influence of the negative pressure difference, the refrigerant can more easily flow back from the downstream through the annular gap c via the bypass hole 212, then merge with the central jet and pass through the silencing mesh 321. If the bypass hole 212 is too far from the valve port 12, the negative pressure difference becomes smaller or even positive, causing the refrigerant in the central jet to flow towards the annular gap c through the bypass hole 212, resulting in some refrigerant not flowing through the silencing mesh for noise reduction.

[0105] Furthermore, even under fully open or wide-open conditions, the refrigerant can mainly flow out through the silencer block 22 of the flow channel 211. After the refrigerant flows out through the silencer block 22, the sound energy is absorbed and weakened. If there are air bubbles in the refrigerant, they will be refined into small air bubbles, avoiding the noise generated by the rupture of large air bubbles and reducing the noise level.

[0106] Regardless of whether it's in a small opening condition or a fully or large opening condition, the bypass hole 212 is close to the valve port 12, shortening the path from the valve port 12 to the bypass hole 212. Even when the silencing mesh 221 of the silencing block 22 is blocked by impurities, the fluid can still flow out through the bypass hole 212 to the annular gap c, without affecting the normal throttling of the electronic expansion valve or causing the valve body 10 to become blocked, thus maintaining the normal throttling function of the electronic valve.

[0107] The table below shows the minimum distance H from the center of bypass hole 212 to valve port 12. b Noise levels corresponding to different sizes (the noise level of the electronic expansion valve without the above-mentioned silencing structure in the second connecting pipe 1B is 45.57dB):

[0108] Hb size / mm 4 6 8 10 12 14 Noise level in dB(A) 38.97 38.96 39.03 39.09 41.25 42.51

[0109] Based on the content of the table above and in combination Figure 7 The noise levels can be clearly compared with H b The size range of 4mm-10mm provides better noise control. Although the noise level increases when the size is greater than 10mm, it is still less than the noise level of 45.57dB of the electronic expansion valve without the above-mentioned silencing structure.

[0110] Electronic expansion valves offer higher control precision and faster response times, making them suitable for refrigeration systems requiring precise temperature control or variable load operation.

[0111] This utility model also proposes a refrigeration device, which can be a household air conditioner (inverter air conditioner), a commercial freezer, an industrial refrigeration system, a cold chain logistics equipment, a heat pump system, etc.

[0112] The refrigeration equipment includes the aforementioned electronic expansion valve. The specific structure of the electronic expansion valve is as described in the above embodiments. Since this refrigeration equipment adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated here.

[0113] The above description is merely an exemplary embodiment of the present utility model and does not limit the scope of protection of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present utility model.

Claims

1. An electronic expansion valve, characterized in that, include: A valve body having a valve cavity and a valve port communicating with the valve cavity; A first connecting pipe is disposed on the periphery of the valve body and connects to the valve cavity; A second connecting pipe is located at the bottom of the valve body and communicates with the valve cavity; and An annular assembly includes an annular base and a journal coaxially disposed with the annular base. The annular base is disposed inside the first connecting pipe or the second connecting pipe. The outer diameter of the journal is smaller than the outer diameter of the annular base. An annular gap exists between the outer side of the journal and the inner wall of the pipe. The annular assembly is axially provided with a flow guide channel. The journal is provided with a bypass hole connecting the flow guide channel and the annular gap. A noise-absorbing block is disposed within the flow channel, and the noise-absorbing block includes at least one noise-absorbing mesh communicating with the flow channel.

2. The electronic expansion valve as described in claim 1, characterized in that, The cross-sectional area of ​​the sound-absorbing mesh is greater than the total cross-sectional area of ​​the bypass holes.

3. The electronic expansion valve as described in claim 1, characterized in that, The ratio of the cross-sectional area of ​​the bypass hole to that of the valve port is in the range of 1-1.

5.

4. The electronic expansion valve as described in claim 1, characterized in that, The ratio of the minimum cross-sectional area of ​​the annular gap to the cross-sectional area of ​​the valve port is in the range of 1-1.

5.

5. The electronic expansion valve as described in claim 1, characterized in that, The minimum distance of the annular gap is H. c 0.2mm < H c <2mm.

6. The electronic expansion valve as described in claim 1, characterized in that, Multiple bypass holes are provided at circumferential intervals along the journal neck.

7. The electronic expansion valve as described in claim 1, characterized in that, The flow channel runs through the annular base and the journal.

8. The electronic expansion valve as described in claim 1, characterized in that, The bypass hole is closer to the valve port than the silencer block.

9. The electronic expansion valve as described in claim 1, characterized in that, The journal shaft is provided with a mounting groove at one end away from the annular base, the inner diameter of which is larger than the inner diameter of the flow channel, and the noise reduction block is installed in the mounting groove.

10. The electronic expansion valve as described in claim 9, characterized in that, The journal shaft is also provided with a tapered opening that gradually widens away from the muffler block, and the tapered opening is connected to the mounting groove.

11. The electronic expansion valve as claimed in claim 1, characterized in that, The annular base and the journal are integrally machined.

12. The electronic expansion valve as claimed in claim 1, characterized in that, The inner wall of the first connecting pipe or the second connecting pipe is provided with an abutting protrusion that abuts against the annular base in the direction away from the valve cavity.

13. The electronic expansion valve as described in claim 12, characterized in that, The abutment protrusions are spaced two apart, and the two abutment protrusions define a groove for mounting the annular base.

14. The electronic expansion valve as claimed in claim 1, characterized in that, The annular base is located on the second connecting pipe, and the minimum distance between the surface of the silencing block near the valve body and the valve port of the valve body that connects to the second connecting pipe is H, where H≤20mm.

15. The electronic expansion valve as claimed in claim 1, characterized in that, The height of the annular base is H. a The minimum distance from the center of the bypass hole to the valve port is H. b Satisfying 3mm≤H a <H b ≤10mm.

16. A refrigeration device comprising an electronic expansion valve as claimed in any one of claims 1 to 15.

Images