An electronic expansion valve with a muffler structure and a method thereof

Abstract

The present invention discloses an electronic expansion valve with a muffler structure and a method, belonging to the field of valve technology. The muffler chamber structure of the device is arranged on the valve seat in the circumferential direction of the straight section, including an inner cavity, a through hole, a spring, a baffle and a sub-coil; an inner cavity is opened in the valve seat, the inner cavity is connected to the straight section through the through hole, and a spring is fixed to the inner wall of the inner cavity away from the valve port; the elastic force direction of the spring is perpendicular to the axial direction of the straight section, and a magnetic baffle is connected to the outer end; the plate size of the baffle is adapted to the inner wall surface of the fixed spring to adjust the volume of the inner cavity adjacent to the valve port; a sub-coil is wound on the valve seat located on the outer periphery of the inner cavity; a pulse signal is input to the sub-coil to control the baffle to move along the radial direction of the inner cavity, thereby changing the volume of the inner cavity adjacent to the valve port. The present invention achieves the effect of dynamically eliminating the flow noise of the electronic expansion valve by arranging a special muffler chamber structure at the outlet of the electronic expansion valve, and its muffler frequency is flexibly adjustable.

Description

Technical Field

[0001] The invention belongs to the technical field of valves, and in particular relates to an electronic expansion valve with a muffler structure and a method. Background Art

[0002] With the improvement of people's living standards, refrigeration equipment such as air conditioners, refrigerators, and freezers are becoming more and more popular and have a huge market. However, the noise problem of the refrigeration system has always troubled users and has become a pain point in the refrigeration field. The noise in the refrigeration system is mainly generated by the more drastic changes in the state of the refrigerant, especially from the throttling elements and the pipe sections connected to them, such as electronic expansion valves, capillary cores, and thermal expansion valves. Among them, the electronic expansion valve has a large turbulent kinetic energy and more vortices due to the throttling expansion effect, and a throttling phase change phenomenon occurs, which produces a jet containing a large number of bubbles, impacting the pipe wall and causing large fluid pressure fluctuations, resulting in significant flow noise here, usually sharp buzzing and howling sounds, which have a bad impact on user comfort.

[0003] Currently, most noise reduction-related patents focus on the control of the refrigeration system itself, while optimization of the valve itself is more common in valves in other fields, such as check valves, flow control valves, etc., and there are fewer optimizations of the structure of the electronic expansion valve in the refrigeration system itself for noise. The difficulty in optimizing the valve structure lies mainly in the fact that the flow state of the refrigerant in the refrigeration system (including density, dryness, pressure, flow shape, etc.) varies more complexly. With different refrigeration conditions and in different start-up and shutdown stages, the flow state of the refrigerant varies and the noise characteristics are different. Fixed-shaped valves and additional noise reduction structures are often difficult to meet the noise reduction requirements under multiple flow conditions at the same time. These noise reduction structures include: adding porous media, modifying the shape of the pipes before and after the valve, adding porous plates, etc.

[0004] In summary, the flow noise problem of the electronic expansion valve in the refrigeration system is still a pain point problem that needs to be solved urgently. At the same time, traditional noise reduction methods often cannot meet the requirements of complex working conditions of the refrigeration system. Therefore, it is necessary to propose a new type of electronic expansion valve with simple form and high feasibility, while meeting the requirements of flexible and adjustable noise reduction structure, and reasonably matching the noise reduction structure with the flow noise characteristics, so as to achieve good noise reduction effect and improve user experience. Summary of the invention

[0005] The present invention aims to solve at least one of the above technical problems in the prior art to a certain extent. The present invention aims to provide an electronic expansion valve with a muffler structure and a method, which can reduce the noise generated by the refrigerant during the throttling expansion process.

[0006] The specific technical solutions adopted by the present invention are as follows:

[0007] In a first aspect, the present invention provides an electronic expansion valve with a muffler structure, comprising a muffler chamber structure portion arranged at a valve port; the valve port is opened at the center of a valve seat, and can connect a flow inlet and a flow outlet when a valve core component is opened; along a fluid flow direction, the valve port comprises a first conical portion, a straight section portion, and a second conical portion portion coaxially arranged in sequence; the first conical portion portion is a conical chamber that gradually shrinks from top to bottom, and the bottom opening is connected to the vertical straight section portion; the second conical portion portion is a conical chamber that gradually expands from top to bottom, and the top opening is connected to the straight section portion, and the bottom opening is connected to the flow outlet;

[0008] The silencer cavity structure is arranged on the valve seat in the circumference of the straight section, and includes an inner cavity, a through hole, a spring, a baffle and a sub-coil; an inner cavity is opened in the valve seat, the inner cavity is connected with the straight section through the through hole, and a spring is fixed on the inner wall of the inner cavity away from the valve port; the elastic force direction of the spring is perpendicular to the axial direction of the straight section, and a magnetic baffle is connected to the outer end; the plate size of the baffle is adapted to the inner wall surface of the fixed spring to adjust the volume of the inner cavity adjacent to the valve port; a sub-coil is wound on the valve seat located at the periphery of the inner cavity; a pulse signal is input to the sub-coil to control the baffle to move along the radial direction of the inner cavity, thereby changing the volume of the inner cavity adjacent to the valve port.

[0009] Preferably, the inner cavity is an annular chamber, which is coaxially arranged with the straight section.

[0010] Preferably, there are at least two inner cavities, which are evenly distributed in the circumferential direction at the same horizontal plane in the valve seat.

[0011] Furthermore, the inner cavity is a cylindrical chamber.

[0012] Preferably, the through hole is a cylindrical hole, and its axial direction is perpendicular to the axial direction of the straight section.

[0013] Preferably, the baffle is an arc-shaped structure for matching with the inner wall of the inner cavity.

[0014] Preferably, the baffle is dynamically sealed or gap-fitted with the inner wall of the inner cavity.

[0015] Preferably, the plate surface of the baffle is perpendicular to the axial direction of the spring.

[0016] In a second aspect, the present invention provides a control method of an electronic expansion valve with a muffler structure using any one of the first aspects, which is as follows:

[0017] After the electronic expansion valve is opened, the fluid flows from the flow inlet through the valve port to the flow outlet; as the fluid flows, sound waves also propagate in the passage; when the incident sound wave reaches the through hole, the liquid column in the through hole vibrates, and a part of the sound wave enters the inner cavity, causing the fluid therein to move, and the sound wave is converted into other energy and dissipated, thereby achieving a noise reduction effect; in this process, by adjusting the input pulse signal of the sub-coil, the baffle is controlled to move along the radius of the inner cavity, thereby changing the volume of the inner cavity adjacent to the valve port, so that the noise reduction frequency range of the inner cavity is adjusted, and the noise reduction frequency of the inner cavity is kept always equivalent to the flow noise frequency.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) The present invention achieves the effect of dynamically eliminating the flow noise of the electronic expansion valve by arranging a special silencer cavity structure at the outlet of the electronic expansion valve, and the silencer frequency is flexibly adjustable.

[0020] 2) When the fluid passes through the electronic expansion valve, a large noise is generated due to the throttling effect. The frequency domain characteristics of the sound pressure intensity of the flow noise are affected by the state parameters of the flow inlet fluid. The muffler structure of the present invention is based on the Helmholtz muffler principle, which can make the noise pressure wave energy dissipate therein, thereby achieving a muffler effect. The volume of the inner cavity of the present invention is adjustable, which can ensure that the muffler frequency range of the muffler structure is equivalent to the flow noise frequency range to ensure the muffler effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the electronic expansion valve of the present invention;

[0022] Figure 2 It is a schematic diagram of the silencing principle of the electronic expansion valve of the present invention;

[0023] Figure 3 yes Figure 1 A partial enlarged view of the middle valve core component and valve seat;

[0024] Figure 4 It is an enlarged view of the muffler chamber structure of the electronic expansion valve of the present invention.

[0025] Explanation of symbols in the figure: x is the opening of the electronic expansion valve, Δs is the displacement of the baffle along the radial direction;

[0026] Valve body 1, magnetic rotor 2, valve stem 3, shell 4, nut component 5, pipe section 6, valve core component 11, flow inlet 12, valve seat 13, valve port 14, flow outlet 15, first conical surface part 16, straight section part 17, muffler cavity structure part 18, inner cavity 18', through hole 18", second conical surface part 19, spring 20, baffle 21, sub-coil 22. DETAILED DESCRIPTION

[0027] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the descriptions involving orientation, such as up, down, left, right, etc., the orientations or positional relationships indicated are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention; if there are references to ordinal numbers such as "first, second", etc., they are only used to distinguish technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0029] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0030] like Figure 1 and 2 As shown, an electronic expansion valve with a silencer structure provided by the present invention, in addition to the valve body 1, magnetic rotor 2, valve stem 3, shell 4, nut component 5 and pipe section 6 conventionally arranged in the prior art, the electronic expansion valve mainly improves the structure of the valve port 14, that is, a silencer cavity structure part 18 is arranged at the valve port 14, which can dynamically eliminate the flow noise of the electronic expansion valve by using the Helmholtz silencer principle.

[0031] First, the conventional components of the electronic expansion valve of the present invention are briefly described.

[0032] In the device of the present invention, the top of the valve body 1 is sealedly connected to the shell 4, and the side wall and the bottom of the valve body 1 are respectively provided with pipe sections 6. The pipe section 6 of the side wall is connected to the inner cavity of the valve body 1 and serves as a flow inlet 12, and the pipe section 6 of the bottom is connected to the inner cavity of the valve body 1 and serves as a flow outlet 15. A valve core assembly is vertically arranged in the inner cavity of the valve body 1, and a valve seat 13 is arranged at the bottom. The valve can be opened and closed by the cooperation between the valve core assembly and the valve seat 13. The top of the valve core assembly is coaxially connected to the valve stem 3, and the valve stem 3 is partially located in the inner cavity of the valve body 1 and partially located in the shell 4. A nut component 5 is fixedly sleeved on the outer periphery of the part of the valve stem 3 located in the shell 4. The nut component 5 has an external thread opened in the axial direction, and the external thread sleeve is connected to a magnetic rotor 2 that can rotate in the circumferential direction, and a coil (not shown in the figure) is wound around the outer side of the shell 4 located outside the magnetic rotor 2. In actual use, in order to adjust the flow control changes after connecting to the refrigeration system, an appropriate pulse signal is applied to the coil, and the magnetic rotor 2 can rotate under the action of the coil. At the same time, the nut component 5 moves up and down under the thread transmission of the magnetic rotor 2. The nut component 5 drives the valve core 11 to move up and down to realize the flow control of the refrigeration system.

[0033] It should be pointed out that, for the components belonging to the prior art that have not been improved in the electronic expansion valve of the present invention, such as the magnetic rotor 2, the nut component 5, the valve stem 3, the shell 4, the coil, etc., reference can be made to the relevant technical structure of the existing electronic expansion valve, and they can be completely replaced with a structure that can achieve the same function. The present invention does not limit them, and technicians can apply the technical solution of the present invention to all types of electronic expansion valve structures.

[0034] The electronic expansion valve structure of the present invention should realize the following functions: the electronic expansion valve can ensure that the valve core component 11 produces parallel displacement, and this displacement can only occur along the central axis of the valve seat 13. Figure 3 The valve opening x is adjustable, and the opening x range is 0 to 2000pls to meet the flow requirements under different refrigeration conditions as much as possible.

[0035] Reference Figure 2 When the electronic expansion valve is connected to the refrigeration system, the refrigerant state parameters of the flow inlet 12 are determined by the refrigeration cycle state. The fluid generates relatively large noise during the throttling and expansion process. The position with relatively large noise sound pressure is generally located from the valve port 14 to the flow outlet 15. Therefore, the present invention mainly improves the structure at the valve port 14. Under the improved structure of the present invention, according to the Helmholtz muffler principle, the muffler cavity structure part 18 of the valve port 14 can weaken the noise of the valve port 14. When the noise pressure wave of the fluid passes through the muffler cavity structure part 18, the liquid column vibrates in the through hole 18", and pulsating energy loss occurs, thereby achieving a muffler effect.

[0036] The improved structure of the present invention will be described in detail below.

[0037] In the device of the present invention, Figure 4 As shown, the valve port 14 is opened at the center of the valve seat 13, and can connect the flow inlet 12 and the flow outlet 15 when the valve core component 11 is opened. Along the fluid flow direction, the valve port 14 includes a first conical portion 16, a straight section 17, and a second conical portion 19 that are coaxially arranged in sequence. The first conical portion 16 is a conical chamber that gradually shrinks from top to bottom, and the bottom opening is connected to the vertical straight section 17. The second conical portion 19 is a conical chamber that gradually expands from top to bottom, and the top opening is connected to the straight section 17, and the bottom opening is connected to the flow outlet 15.

[0038] The present invention opens the central flow channel of the valve seat 13 so that the fluid passes through the first conical portion 16, the straight section 17 and the second conical portion 19 in sequence when passing through the valve port 14, thereby causing the fluid to undergo a pressure reduction phase change caused by throttling at the tapered throat of the first conical portion 16. The fluid flows stably in the straight section 17 to prepare for silencer, and the fluid is further depressurized at the position of the second conical portion 19 due to the gradual expansion.

[0039] In the device of the present invention, Figure 4 As shown, the muffler cavity structure 18 is arranged on the valve seat 13 in the circumference of the straight section 17, and mainly includes an inner cavity 18', a through hole 18", a spring 20, a baffle 21 and a sub-coil 22. An inner cavity 18' is opened in the valve seat 13, and the inner cavity 18' is connected with the straight section 17 through the through hole 18", and a spring 20 is fixed to the inner wall of the inner cavity 18' away from the valve port 14. The elastic force direction of the spring 20 is perpendicular to the axial direction of the straight section 17, and a magnetic baffle 21 is connected to the outer end. The plate size of the baffle 21 is adapted to the inner wall surface of the fixed spring 20 to adjust the volume of the inner cavity 18' adjacent to the valve port 14. A sub-coil 22 is wound on the valve seat 13 located at the outer periphery of the inner cavity 18'. A pulse signal is input to the sub-coil 22 to control the baffle 21 to move along the radial direction of the inner cavity 18', thereby changing the volume of the inner cavity 18' adjacent to the valve port 14.

[0040] As a preferred embodiment of the present invention, the inner cavity 18' has the following two settings: first, the inner cavity 18' can be an entire annular chamber, which is coaxially arranged with the straight section 17; second, there are at least two inner cavities 18', and all inner cavities 18' are evenly distributed along the circumference at the same horizontal plane in the valve seat 13, and each inner cavity 18' can adopt a cylindrical chamber.

[0041] As a preferred embodiment of the present invention, the through hole 18" can be a cylindrical hole, and its axial direction is perpendicular to the axial direction of the straight section 17. The baffle 21 is an arc-shaped structure, which is used to match the inner wall of the inner cavity 18'. A dynamic seal or a gap fit can be used between the baffle 21 and the inner wall of the inner cavity 18'. The plate surface of the baffle 21 can be vertically arranged to the axial direction of the spring 20. The baffle 21 can be made of ferromagnetic materials such as nickel alloy, iron-cobalt-nickel alloy, etc.

[0042] The principle of the muffler cavity structure 18 of the present invention adopting this arrangement is as follows:

[0043] After the noise at the valve port 14 is analyzed in the frequency domain, the frequency domain characteristics of the noise sound pressure can be obtained, and the frequency domain characteristics indicate the frequency segment with a larger noise sound pressure. Generally, the frequency domain characteristics of this noise are affected by the state parameters of the fluid flowing into the inlet 12, and the state parameters of the fluid include velocity, pressure, dryness, density and manifold. Generally, when the noise sound pressure is in a range higher than 40dB, it can be considered as large. This sound pressure range corresponds to a continuous frequency domain range, which is called the noise frequency range.

[0044] When the sizes of the inner cavity 18' and the through hole 18" of the muffler cavity structure 18 of the valve port 14 are determined, the muffler frequency range corresponding to the muffler cavity structure 18 is determined. Generally, the flow rate changes and the refrigerant state parameters in the refrigeration system vary greatly, which leads to a large variation in the frequency domain characteristics of the flow noise. In this case, the muffler frequency range corresponding to the muffler cavity structure 18 may not match the noise frequency range, resulting in poor muffler effect.

[0045] Therefore, in order to dynamically adjust the silencing frequency range and make the silencing frequency range match the noise frequency range, the present invention also attaches a spring 20 to the inner wall of the inner cavity 18' away from the valve port 14, and the spring 20 is connected to the arc-shaped baffle 21. The baffle 21 is magnetic and constrained by the spring 20. A sub-coil 22 is wound around the outside of the valve body 1. A pulse signal can be input into the sub-coil 22 to control the baffle 21 to move along the radial direction of the inner cavity 18' and generate a displacement Δs. The volume of the inner cavity 18' is adjusted by the change of Δs, and at the same time, the silencing frequency range of the silencing cavity structure 18 is adjusted.

[0046] Based on the above-mentioned feedback adjustment mechanism, the relationship between the input pulse signal of the sub-coil 22, the volume of the inner cavity 18' and the noise reduction frequency range parameters needs to be determined according to the working conditions before use. At the same time, the relationship between the refrigerant inlet state parameters and the noise frequency range needs to be determined according to the working conditions before use to ensure the noise reduction effect of the electronic expansion valve of the present invention.

[0047] Based on the above electronic expansion valve with a muffler structure, the present invention further provides a control method, which is specifically as follows:

[0048] When the electronic expansion valve is opened, the fluid flows from the flow inlet 12 to the flow outlet 15 through the valve port 14. As the fluid flows, sound waves also propagate in the passage. When the incident sound wave reaches the through hole 18", the liquid column in the through hole 18" vibrates, and a part of the sound wave enters the inner cavity 18', causing the fluid therein to move, so that the sound wave is converted into other energy and dissipated, thereby achieving a noise reduction effect. In this process, by adjusting the input pulse signal of the sub-coil 22, the baffle 21 is controlled to move along the radial direction of the inner cavity 18', thereby changing the volume of the inner cavity 18' adjacent to the valve port 14, so that the noise reduction frequency range of the inner cavity 18' is adjusted, and the noise reduction frequency of the inner cavity 18' is always kept equivalent to the flow noise frequency.

[0049] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. An electronic expansion valve with a muffler structure, characterized in that: The invention comprises a muffler cavity structure part (18) arranged at the valve port (14); the valve port (14) is opened at the center of the valve seat (13), and can connect the flow inlet (12) and the flow outlet (15) when the valve core component (11) is opened; along the fluid flow direction, the valve port (14) comprises a first conical surface part (16), a straight section part (17) and a second conical surface part (19) which are coaxially arranged in sequence; the first conical surface part (16) is a conical cavity which gradually decreases from top to bottom, and the bottom opening is connected to the vertical straight section part (17); the second conical surface part (19) is a conical cavity which gradually expands from top to bottom, and the top opening is connected to the straight section part (17), and the bottom opening is connected to the flow outlet (15); The muffler cavity structure (18) is arranged on the valve seat (13) in the circumferential direction of the straight section (17), and comprises an inner cavity (18'), a through hole (18"), a spring (20), a baffle (21) and a sub-coil (22); an inner cavity (18') is opened in the valve seat (13), the inner cavity (18') is connected with the straight section (17) through the through hole (18"), and a spring (20) is fixed to the inner wall of the inner cavity (18') away from the valve port (14); the elastic force direction of the spring (20) is in line with the straight section (17); 7) is axially vertical, and a magnetic baffle (21) is connected to the outer end; the plate size of the baffle (21) is adapted to the inner wall surface of the fixed spring (20) to adjust the volume of the inner cavity (18') adjacent to the valve port (14); a sub-coil (22) is wound on the valve seat (13) located at the outer periphery of the inner cavity (18'); a pulse signal is input to the sub-coil (22) to control the baffle (21) to move along the radial direction of the inner cavity (18'), thereby changing the volume of the inner cavity (18') adjacent to the valve port (14).

2. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: The inner cavity (18') is an annular chamber and is coaxially arranged with the straight section (17).

3. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: The inner cavities (18') have at least two and are evenly distributed along the circumferential direction at the same horizontal plane in the valve seat (13).

4. The electronic expansion valve with a muffler structure according to claim 3, characterized in that: The inner cavity (18') is a cylindrical cavity.

5. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: The through hole (18") is a cylindrical hole, and its axial direction is perpendicular to the axial direction of the straight section (17).

6. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: The blocking piece (21) is an arc-shaped structure and is used to match the inner wall of the inner cavity (18').

7. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: There is a dynamic seal or clearance fit between the baffle (21) and the inner wall of the inner cavity (18').

8. The electronic expansion valve with a muffler structure according to claim 1, characterized in that: The plate surface of the blocking piece (21) is perpendicular to the axial direction of the spring (20).

9. A control method using the electronic expansion valve with a muffler structure according to any one of claims 1 to 8, characterized in that: The details are as follows: After the electronic expansion valve is opened, the fluid flows from the flow inlet (12) to the flow outlet (15) through the valve port (14); as the fluid flows, sound waves also propagate in the passage; when the incident sound wave reaches the through hole (18"), the liquid column in the through hole (18") vibrates, and a part of the sound wave enters the inner cavity (18'), causing the fluid therein to move, so that the sound wave is converted into other energy and dissipated, thereby achieving a noise reduction effect; in this process, by adjusting the input pulse signal of the sub-coil (22), the baffle (21) is controlled to move along the radial direction of the inner cavity (18'), thereby changing the volume of the inner cavity (18') adjacent to the valve port (14), so that the noise reduction frequency range of the inner cavity (18') is adjusted, and the noise reduction frequency of the inner cavity (18') is always kept equivalent to the flow noise frequency.

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