A noise-reducing exhaust valve for a scroll compressor

Abstract

This invention discloses a noise-reducing exhaust valve for a scroll compressor, belonging to the field of refrigeration compressor technology. Technical solution: An exhaust valve plate and an exhaust valve limiter are installed at the fixed scroll exhaust port; the exhaust valve limiter is fixed to the fixed scroll exhaust port via bolt holes, and its vent hole facing the valve plate has a concave surface matching the elliptical concave structure of the valve plate. The semi-elliptical spherical concave structure is formed by rotating an elliptical curve around its major axis, with the semi-major axis a and semi-minor axis b satisfying 0.4≤a / b≤1.6. The concave depth h is equal to the semi-major axis a, and the ratio of h to the diameter d of the matching fixed scroll exhaust port is 0.3≤h / d≤0.6. The valve plate base of the exhaust valve plate has the same thickness as the elliptical concave structure of the valve plate. Beneficial effects: This invention utilizes the acoustic resonance characteristics of an elliptical cavity to form a multi-stage expansion silencing effect during exhaust, effectively reducing pressure pulsation and aerodynamic noise at the exhaust port, while ensuring the structural strength and response sensitivity of the valve plate.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration compressor technology, specifically relating to a scroll compressor exhaust valve, and more particularly to an exhaust valve with an elliptical concave structure for noise reduction. Background Technology

[0002] Scroll compressors are widely used in air conditioning, heat pumps, and refrigeration systems due to their high efficiency, low vibration, and low noise. A scroll compressor achieves continuous compression of the refrigerant by forming a compression chamber through the meshing of a moving scroll and a stationary scroll. The compressed, high-pressure refrigerant is discharged through the exhaust port at the center of the stationary scroll and enters the high-pressure chamber.

[0003] However, during the exhaust process, significant pressure pulsations occur at the exhaust port due to the periodic changes in the compression chamber volume and the periodic opening and closing of the exhaust port. These pressure pulsations propagate outward in the form of airflow pulses and are one of the main sources of aerodynamic noise in scroll compressors. This aerodynamic noise problem is particularly pronounced under low-speed, high-load conditions, where the exhaust airflow velocity is high and the pressure pulsation amplitude is high.

[0004] In existing technologies, expansion mufflers, resonant cavity mufflers, or insert pipe structures are commonly used to reduce exhaust noise. However, these solutions mostly focus on the pipeline design of the exhaust channel, with insufficient attention paid to the structural optimization of the exhaust valve plate itself. Traditional flat or simple arc-shaped valve plates can ensure sealing, but their ability to suppress pressure pulsation is limited. Some studies have attempted to add grooves or protrusions to the valve plate to change airflow characteristics, but these lack systematic acoustic design, resulting in insignificant noise reduction effects and potentially affecting the structural strength and dynamic response characteristics of the valve plate. Therefore, there is an urgent need for an exhaust valve plate structure that can effectively reduce exhaust pressure pulsation, ensure good noise reduction, and maintain the reliability and response sensitivity of the valve plate structure. Summary of the Invention

[0005] In order to solve the technical problems existing in the prior art, the present invention aims to provide a noise reduction exhaust valve for a scroll compressor. By optimizing the geometric structure of the exhaust valve plate and utilizing the acoustic characteristics of the elliptical cavity, a multi-stage expansion silencing effect is formed at the exhaust port, which effectively suppresses pressure pulsation and reduces aerodynamic noise.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A noise-reducing exhaust valve for a scroll compressor includes an exhaust valve plate and an exhaust valve limiter, which are installed at the exhaust port of a fixed scroll compressor. The exhaust valve limiter is fixed on the fixed vortex, and the contact surface of the exhaust valve limiter's vent hole facing the exhaust valve plate is concave. The exhaust valve plate is composed of a valve plate base and an elliptical concave structure. The elliptical concave structure is located on the side of the valve plate base facing the fixed vortex exhaust port of the fixed vortex. The semi-major axis a and semi-minor axis b of the elliptical concave structure of the valve plate satisfy 1.2≤a / b≤1.6, the concavity depth h of the elliptical concave structure of the valve plate is equal to the semi-major axis a, and the ratio of the concavity depth h to the diameter d of the fixed vortex exhaust port satisfies 0.3≤h / d≤0.6. The thickness t of the valve plate substrate is consistent with that of the elliptical concave structure of the valve plate.

[0007] Furthermore, the contour curve of the elliptical concave structure of the valve plate satisfies the standard ellipse equation, and its major axis is aligned with the axial direction of the compressor exhaust port.

[0008] Furthermore, the bottom of the elliptical concave structure of the valve plate is a smooth curved surface with a radius of curvature R ≥ 2 mm.

[0009] Furthermore, the thickness t of the exhaust valve plate is 0.3mm~0.5mm.

[0010] Furthermore, the ratio h / d of the concave depth h to the diameter d of the fixed vortex exhaust port is 0.4~0.5.

[0011] Furthermore, the ratio of the semi-major axis a to the semi-minor axis b of the elliptical concave structure of the valve plate is 1.5.

[0012] Furthermore, the exhaust valve limiter is fixed to the fixed vortex via bolt holes, and the exhaust valve limiter is provided with vent holes.

[0013] Furthermore, the contact surface of the exhaust valve limiter toward the exhaust valve plate is a concave surface that matches the elliptical concave structure of the valve plate.

[0014] Furthermore, the exhaust valve limiter restricts the maximum opening height of the exhaust valve disc to 6mm.

[0015] Furthermore, the diameter of the vent hole on the exhaust valve limiter is 5mm.

[0016] The beneficial effects of this invention are: Compared with the prior art, the scroll compressor noise reduction exhaust valve of the present invention has the following technical features and beneficial effects: 1. This invention uses an elliptical concave structure for the valve plate with a ratio of semi-major axis a to semi-minor axis b of 1.2 to 1.6 and a concave depth h to exhaust port diameter d of 0.3 to 0.6. By utilizing the acoustic resonance characteristics of the elliptical cavity, a multi-stage expansion silencing effect is formed at the exhaust port, which can effectively suppress the pressure pulsation amplitude caused by the periodic exhaust of the compression chamber, thereby significantly reducing the aerodynamic noise of the scroll compressor. 2. The non-axisymmetric geometry of the elliptical concave structure of the valve plate in this invention makes the chamber have different acoustic lengths in different directions, which can destroy the periodic reflection of pressure waves at a specific frequency, so that the reflected sound waves generate a phase difference and cancel each other out, thereby expanding the effective noise reduction frequency range to cover the main noise frequency band of the scroll compressor, avoiding the single-frequency standing wave resonance problem that is easy to be generated by traditional circular or symmetrical cavities. 3. By ensuring that the valve plate substrate and the elliptical concave structure of the valve plate have the same thickness, this invention ensures the uniformity of stress distribution during repeated opening and closing of the valve plate, avoiding the stress concentration problem commonly found in the groove or transition area of ​​traditional variable thickness valve plates; at the same time, the smooth curved surface design with a bottom curvature radius of greater than or equal to 2mm of the elliptical concave structure of the valve plate further reduces the risk of fatigue crack initiation and significantly improves the service life of the exhaust valve plate. 4. The uniform thickness distribution design in this invention avoids the difference in elastic characteristics caused by abrupt changes in local structure, ensuring the consistency of the overall elasticity of the valve plate, enabling it to quickly follow the pressure changes in the compression chamber and open and close in a timely manner, effectively shortening the opening and closing response time, and ensuring the volumetric efficiency and reliability of the compressor under high frequency or variable operating conditions. 5. By preferably controlling the ratio of the concave depth h to the exhaust port diameter d to 0.4~0.5 and the ratio of the semi-major axis a to the semi-minor axis b to 1.5, the present invention provides sufficient expansion space to suppress noise while ensuring that the valve plate has suitable structural rigidity, so that it is not easy to undergo excessive deformation under high pressure conditions, thus achieving the best balance between noise reduction performance and structural reliability. 6. The elliptical concave structure of the valve plate of the present invention is formed by rotating an elliptical curve around its major axis, and the overall thickness of the valve plate remains consistent. This structure can be formed by conventional processes such as stamping, spinning or electrochemical processing, without the need for complex variable thickness processing or special equipment. It has good process adaptability and is suitable for low-cost and high-efficiency mass production in the compressor industry. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic diagram of the overall structure of the fixed vortex and exhaust valve of the present invention; Figure 2 for Figure 1 Overall structural sectional view; Figure 3 This is a schematic diagram of the assembly of the exhaust valve plate and the limiter of the present invention; Figure 4 This is a schematic diagram of the exhaust valve limiter of the present invention; Figure 5 This is a schematic diagram of the exhaust valve plate of the present invention; Figure 6 This is a schematic diagram of the cross-sectional outline of the exhaust valve plate of the present invention; In the figure, the following labels are used: 1-fixed vortex, 2-fixed vortex inlet, 3-exhaust valve, 1.1-fixed vortex compression chamber, 1.2-fixed vortex exhaust port, 3.1-exhaust valve limiter, 3.1.1-bolt hole, 3.1.2-vent hole, 3.2-exhaust valve plate, 3.2.1-valve plate base, 3.2.2-valve plate elliptical concave structure. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The following description, in conjunction with the accompanying drawings... Figure 1-6 Further explanation is provided regarding the noise reduction exhaust valve for scroll compressors.

[0019] Example 1 A noise-reducing exhaust valve for a scroll compressor includes an exhaust valve 3, an exhaust valve limiter 3.1, and an exhaust valve plate 3.2, for installation at the exhaust port 1.2 of a fixed scroll compressor 1. The fixed scroll compressor 1 includes an inlet 2, a compression chamber 1.1, and an exhaust port 1.2. The exhaust valve plate 3.2 consists of a plate base 3.2.1 and an elliptical concave structure 3.2.2. The elliptical concave structure 3.2.2 is located on the side of the plate base 3.2.1 facing the exhaust port 1.2 of the fixed scroll compressor. The semi-major axis a and semi-minor axis b of the elliptical concave structure satisfy 1.2 ≤ a / b ≤ 1.6, and the ratio of the concave depth h to the diameter d of the fixed scroll compressor exhaust port is 0.3 ≤ h / d ≤ 0.6. Furthermore, the thickness t of the plate base 3.2.1 and the elliptical concave structure 3.2.2 are consistent.

[0020] The contour curve of the elliptical concave structure 3.2.2 of the valve plate satisfies the standard elliptical equation. , where a is the semi-major axis and b is the semi-minor axis, and the direction of the major axis is consistent with the axial direction of the compressor.

[0021] The valve plate has a thickness t of 0.3mm to 0.5mm, and the bottom of the elliptical concave structure 3.2.2 of the valve plate is a smooth curved surface with a radius of curvature R ≥ 2mm.

[0022] The depth h of the elliptical concave structure 3.2.2 of the valve plate is preferably 0.3 to 0.6 times the diameter d of the fixed vortex exhaust port, that is, h = a = (0.3 to 0.6)d.

[0023] The exhaust valve limiter 3.1 is fixed to the fixed vortex 1 through the limiter bolt hole 3.1.1, and the limiter is provided with a vent hole 3.1.2. The contact surface between the limiter and the exhaust valve plate 3.2 is a concave surface that matches the elliptical concave structure 3.2.2 of the valve plate.

[0024] The technical principle of this invention is as follows: Elliptical cavities possess unique acoustic resonance characteristics. When the exhaust gas flows out at high speed from the fixed vortex exhaust port, it first enters the elliptical cavity formed by the elliptical concave structure 3.2.2 of the valve plate. The elliptical concave structure provides a large expansion volume within a limited radial space, while its non-axisymmetric geometry can disrupt the periodic reflection of pressure waves, avoiding standing wave resonance at specific frequencies.

[0025] The ratio of the semi-major axis to the semi-minor axis of the ellipse, a / b, is controlled within the range of 1.2 to 1.6, ensuring sufficient expansion space without causing insufficient valve plate stiffness due to excessive flattening. The ratio of the concave depth h to the exhaust port diameter d is controlled within the range of 0.3 to 0.6, matching the chamber depth with the exhaust port dimensions to ensure that the silencing frequency covers the main noise frequency band of the scroll compressor.

[0026] Maintaining a consistent thickness between the valve plate substrate 3.2.1 and the elliptical concave structure 3.2.2 of the valve plate is one of the key features of this invention. The uniform thickness distribution ensures the uniformity of stress on the valve plate during opening and closing, avoiding the stress concentration problem that occurs at the groove in traditional variable-thickness valve plates. Simultaneously, the consistent thickness guarantees the dynamic response characteristics of the valve plate, enabling it to quickly open and close in response to changes in the compression chamber pressure, thus maintaining the volumetric efficiency of the compressor.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: The expansion chamber formed by the elliptical concave structure 3.2.2 of the valve plate effectively reduces the amplitude of exhaust pressure pulsation. Simultaneously, the asymmetry of the elliptical geometry results in different acoustic lengths of the chamber in different directions, thereby broadening the effective noise reduction frequency range and avoiding resonance peaks at single frequencies. The valve plate design with consistent thickness avoids stress concentration, and the smooth curved surface at the bottom of the elliptical concave structure 3.2.2 further reduces the risk of fatigue cracks, extending the valve plate's service life compared to traditional structures. The uniform thickness distribution ensures consistent valve plate elasticity, resulting in a shorter opening and closing response time and ensuring reliable compressor operation under high-frequency conditions. The elliptical concave structure 3.2.2 can be achieved through processes such as stamping, spinning, or electrochemical machining, making it suitable for mass production.

[0028] Example 2 like Figures 1-6 As shown, the noise-reducing exhaust valve of the scroll compressor of the present invention is installed at the center of the fixed scroll 1, corresponding to the exhaust port 1.2 of the fixed scroll. The exhaust valve 3 consists of an exhaust valve limiter 3.1 and an exhaust valve plate 3.2.

[0029] The exhaust valve plate 3.2 consists of a valve plate base 3.2.1 and a semi-elliptical concave structure 3.2.2, both made of spring steel with a consistent thickness t of 0.3~0.5mm. The semi-elliptical concave structure 3.2.2 is located on the side of the valve plate base 3.2.1 facing the fixed vortex exhaust port 1.2, and is formed by rotating an elliptical curve around its major axis. The ratio of its semi-major axis a to its semi-minor axis b is a / b≈1.5, the concave depth h=a, and the ratio of h to the diameter d of the fixed vortex exhaust port h / d=0.4~0.5, which is within the preferred range that balances noise reduction and structural reliability.

[0030] The contour curve of the elliptical concave structure of the valve plate (3.2.2) satisfies the standard elliptical equation. The major axis is arranged along the compressor axial direction. The bottom of the recess is a smoothly transitioned curved surface with a radius of curvature R≥2mm to avoid stress concentration. The valve plate substrate 3.2.1 is a flat plate portion surrounding the elliptical recessed structure 3.2.2 of the valve plate, with the same thickness as the recessed structure to ensure uniform overall structural strength.

[0031] The exhaust valve limiter 3.1 is fixed to the fixed vortex 1 through the limiter bolt hole 3.1.1. Its contact surface facing the valve plate is a concave surface that matches the elliptical concave structure 3.2.2 of the valve plate, limiting the maximum opening height of the valve plate to 6mm. The limiter is provided with a vent hole 3.1.2 with a diameter of 5mm to ensure smooth exhaust.

[0032] When the pressure inside the compression chamber is higher than the back pressure, the exhaust valve plate 3.2 opens, and the high-pressure airflow is ejected from the fixed vortex exhaust port 1.2 and enters the expansion chamber formed by the elliptical concave structure 3.2.2 of the valve plate. Within this chamber, the airflow undergoes a sudden cross-sectional expansion, reducing the amplitude of the pressure pulsation. Simultaneously, the geometric characteristics of the elliptical cavity cause a phase difference in the reflected sound waves, resulting in the cancellation of some frequencies of sound waves. The airflow then enters the high-pressure chamber through the limiter vent 3.1.2. When the pressure inside the compression chamber decreases, the valve plate closes the exhaust port under the action of elastic force.

[0033] For a scroll compressor with a fixed scroll exhaust port diameter of d=16.4mm, three valve plate elliptical concave structures with different flatness were designed and compared: Low flatness ratio: a / b=1.2, h / d=0.35. This design features an ellipsoid close to a sphere, resulting in high structural stiffness, suitability for high-pressure conditions, and some noise reduction effect.

[0034] Medium flatness ratio: a / b=1.5, h / d=0.45. This scheme achieves a balance between expansion space and structural stiffness, with significantly better noise reduction effect than the previous scheme, while maintaining good dynamic response characteristics.

[0035] High flatness ratio: a / b=1.6, h / d=0.55. This design features a relatively flat ellipsoid with a large expansion ratio, resulting in better noise reduction and making it suitable for applications with strict noise control requirements.

[0036] The above analysis and comparison show that the second parameter scheme achieves the best balance between noise reduction effect and structural reliability.

[0037] Example 3 This embodiment is combined with the appendix Figures 1 to 6 The specific embodiments of the present invention will be described in further detail below.

[0038] like Figure 1 and Figure 2 As shown, the noise-reducing exhaust valve for the scroll compressor provided by this invention is installed at the center of the fixed scroll 1. The fixed scroll 1 is provided with a fixed scroll inlet 2, a fixed scroll compression chamber 1.1, and a fixed scroll exhaust port 1.2. The fixed scroll exhaust port 1.2 is located at the center of the fixed scroll 1 and is used to discharge the high-pressure refrigerant gas that has been compressed within the fixed scroll compression chamber 1.1. The exhaust valve 3 is installed corresponding to the position of the fixed scroll exhaust port 1.2 and is used to control the opening and closing of the exhaust port, and to reduce pressure pulsation and aerodynamic noise generated during the exhaust process.

[0039] Specifically, such as Figures 1 to 4As shown, the exhaust valve 3 consists of an exhaust valve limiter 3.1 and an exhaust valve plate 3.2. The exhaust valve limiter 3.1 has a bolt hole 3.1.1 and a vent hole 3.1.2. The exhaust valve limiter 3.1 is fixedly mounted on the fixed scroll 1 by bolts passing through the bolt hole 3.1.1, thereby pressing and confining the exhaust valve plate 3.2 between the fixed scroll 1 and the exhaust valve limiter 3.1. The function of the exhaust valve limiter 3.1 is to limit the maximum opening height of the exhaust valve plate 3.2, preventing excessive deformation of the valve plate. Simultaneously, the vent hole 3.1.2 serves as an exhaust passage, allowing airflow passing through the valve plate to smoothly enter the high-pressure chamber of the compressor. The contact surface of the exhaust valve limiter 3.1 facing the exhaust valve plate 3.2 is not planar, but rather a concave surface that matches the elliptical concave structure 3.2.2 of the exhaust valve plate 3.2. This concave structure can form a good fit with the surface of the elliptical concave structure 3.2.2 of the valve plate when the valve plate is opened to the maximum position, or leave a uniform gap, thereby providing uniform support and limiting for the valve plate and avoiding excessive local stress.

[0040] like Figure 3 , Figure 5 and Figure 6 As shown, the exhaust valve plate 3.2 is the core component for achieving the noise reduction function of this invention. The exhaust valve plate 3.2 is made entirely of spring steel with good elasticity and fatigue strength, allowing it to open rapidly under exhaust pressure and close quickly after exhaust by its own elastic restoring force. The exhaust valve plate 3.2 is integrally formed from the valve plate base 3.2.1 and the elliptical recessed structure 3.2.2. The valve plate base 3.2.1 is a flat annular area surrounding the elliptical recessed structure 3.2.2, which is used to tightly fit with the sealing surface of the fixed vortex 1 around the fixed vortex exhaust port 1.2 when the valve plate is closed, thus sealing the exhaust port. The elliptical recessed structure 3.2.2 is located on the side of the valve plate base 3.2.1 facing the fixed vortex exhaust port 1.2, that is, the elliptical recessed structure 3.2.2 is recessed away from the fixed vortex exhaust port 1.2 (i.e., towards the exhaust valve limiter 3.1). The valve plate elliptical concave structure 3.2.2 is a semi-elliptical spherical concave structure formed by rotating an elliptical curve around its major axis, and its contour curve satisfies the standard ellipse equation. The major axis of the valve plate elliptical concave structure 3.2.2 is arranged along the compressor axial direction (i.e., the overall flow direction of the exhaust gas), while the minor axis is located in a plane perpendicular to the axial direction. This non-axisymmetric geometry is one of the key features of this invention.

[0041] Regarding the dimensional parameters of the elliptical concave structure 3.2.2 on the valve plate, this invention has imposed strict limitations. The semi-major axis is defined as 'a', the semi-minor axis as 'b', and the concave depth as 'h', where 'h' equals the semi-major axis 'a'. The ratio of the semi-major axis 'a' to the semi-minor axis 'b' satisfies 0.4 ≤ a / b ≤ 1.6. This range ensures that the elliptical concave structure possesses sufficient asymmetry to disrupt the periodic reflection of pressure waves without causing processing difficulties or a decrease in structural stiffness due to excessive flatness. Specifically, in a more preferred embodiment, for example, for a scroll compressor with an exhaust port diameter d = 16.4 mm, a low flatness ratio scheme of a / b = 1.2 (the ellipsoid is close to a sphere, resulting in higher structural stiffness and suitability for high-pressure conditions) can be set, as can a medium flatness ratio scheme of a / b = 1.5 (achieving a balance between expansion space and structural stiffness, resulting in significant noise reduction), and a high flatness ratio scheme of a / b = 1.6 (the ellipsoid is relatively flat, with a large expansion ratio, resulting in better noise reduction). Meanwhile, the ratio of the concave depth h to the diameter d of the fixed scroll exhaust port 1.2 satisfies 0.3≤h / d≤0.6, that is, h =a = (0.3~0.6)d. This proportional relationship ensures that the depth of the expansion cavity formed by the elliptical concave structure matches the size of the exhaust port, so that its silencing frequency can cover the main noise frequency band generated when the scroll compressor is working.

[0042] Furthermore, the overall thickness distribution of the exhaust valve disc 3.2 is another key factor in ensuring its structural reliability and dynamic response characteristics. The thickness t of the disc substrate 3.2.1 and the elliptical concave structure 3.2.2 is consistent, meaning the entire exhaust valve disc 3.2 is a uniform thickness structure. This design avoids the stress concentration phenomenon caused by abrupt changes in thickness in traditional variable-thickness valve discs, resulting in a more uniform internal stress distribution when the disc is subjected to pulsating exhaust pressure and high-speed opening / closing actions, thus significantly improving the fatigue life of the disc. Simultaneously, the uniform thickness also ensures that the entire disc has consistent elastic stiffness, making its dynamic response characteristics uniform and controllable. It can quickly follow the pressure changes within the constant scroll compression chamber 1.1 to open and close, maintaining the volumetric efficiency of the compressor. In this embodiment, the disc thickness t can be selected from any value between 0.3mm and 0.5mm, such as 0.3mm, 0.4mm, or 0.5mm, depending on the actual operating conditions and material strength. In addition, to prevent stress concentration at the bottom apex of the elliptical concave structure 3.2.2 of the valve plate, the bottom is designed as a smoothly transitioning curved surface, and its radius of curvature R is set to be greater than or equal to 2mm, such as R=2mm, R=2.5mm or R=3mm, in order to further disperse stress and improve fatigue resistance.

[0043] The working process and principle of the scroll compressor noise reduction exhaust valve of the present invention are described in detail below with reference to the accompanying drawings. During the operation of the scroll compressor, when the pressure in the fixed scroll compression chamber 1.1 gradually increases with the rotation of the moving scroll and exceeds the pressure on the back pressure side (i.e., the high-pressure chamber side) of the exhaust valve plate 3.2, high-pressure refrigerant gas will be ejected from the fixed scroll exhaust port 1.2. This high-pressure airflow first directly impacts and enters the semi-elliptical spherical cavity formed by the elliptical concave structure 3.2.2 of the valve plate. Due to the sudden entry from the small cross-section channel of the fixed scroll exhaust port 1.2 into the larger volume expansion chamber formed by the elliptical concave structure 3.2.2 of the valve plate, the airflow undergoes a sudden cross-sectional expansion process. According to the principle of aeroacoustics, the sudden cross-sectional expansion will lead to a decrease in airflow velocity and a significant decrease in the amplitude of pressure pulsation, thereby achieving first-stage expansion noise reduction. Meanwhile, the non-axisymmetric geometry of the elliptical cavity plays a crucial role: the cavity has different acoustic lengths in different directions (major and minor axes), which causes the pressure waves (sound waves) entering the cavity to form specific phase differences when reflected on the cavity walls. When these phase-difference reflected waves superimpose with the incident wave, interference cancellation occurs over a wide frequency range, effectively avoiding the single-frequency standing wave resonance phenomenon that is prone to occur in traditional circular symmetrical cavities, thus achieving broadband noise suppression. As the airflow moves further forward, when the airflow flows out from the gap between the edge of the elliptical concave structure 3.2.2 of the valve plate and the exhaust valve limiter 3.1, and finally passes through the vent 3.1.2 on the exhaust valve limiter 3.1, it will again undergo a change in the flow cross-section, forming a secondary expansion silencing effect. Therefore, this invention, through the cooperation of the elliptical concave structure 3.2.2 of the valve plate and the vent 3.1.2 of the limiter, achieves a composite noise reduction effect of multi-stage expansion and interference silencing within a limited axial space. When the pressure in the fixed vortex compression chamber 1.1 drops below the back pressure, the exhaust valve plate 3.2, under the action of its own elastic restoring force, quickly rebounds towards the fixed vortex exhaust port 1.2, so that the valve plate base 3.2.1 is tightly attached to the sealing surface of the fixed vortex 1, thereby closing the exhaust port and preventing high-pressure gas backflow.

[0044] Furthermore, the exhaust valve plate 3.2 of this invention exhibits excellent manufacturing process adaptability. Since the thickness of the valve plate substrate 3.2.1 and the elliptical concave structure 3.2.2 remains consistent, and the semi-elliptical spherical concave structure is formed by rotating an elliptical curve around an axis, this structure can be mass-produced using various conventional metal forming processes. For example, precision stamping can be used, employing a punch and die that match the shape of the elliptical concave structure 3.2.2 to stamp a thin sheet of spring steel; spinning can also be used, allowing the thin metal sheet to gradually adhere to the surface of the rotating elliptical die during rotation; and stress-free forming processes such as electrochemical machining can also be employed. All of these processes ensure the dimensional accuracy and surface quality of the valve plate structure, making it suitable for low-cost, high-efficiency large-scale production in the compressor industry.

[0045] This embodiment employs a systematic acoustic design of the exhaust valve disc 3.2's geometry. Specifically, it defines the ratio range between the semi-major axis a and semi-minor axis b of the elliptical concave structure 3.2.2 of the disc, the ratio range between the concavity depth h and the diameter d of the fixed scroll exhaust port 1.2, and maintains a consistent thickness between the disc substrate 3.2.1 and the concave structure while setting a smooth bottom curvature radius. This effectively solves the problems of poor noise reduction, easy structural fatigue failure, and poor dynamic response characteristics in existing exhaust valves. This invention significantly reduces exhaust pressure pulsation and aerodynamic noise while ensuring the structural strength, service life, and response sensitivity of the disc, providing a highly efficient and reliable noise reduction solution for scroll compressors.

[0046] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A noise-reducing exhaust valve for a scroll compressor, comprising an exhaust valve plate (3.2) and an exhaust valve limiter (3.1), installed at the fixed scroll exhaust port (1.2) of a fixed scroll (1), characterized in that: The exhaust valve limiter (3.1) is fixed on the fixed vortex (1), and the contact surface of the vent hole (3.1.2) of the exhaust valve limiter (3.1) facing the exhaust valve plate (3.2) is concave. The exhaust valve plate (3.2) is composed of a valve plate base (3.2.1) and a valve plate elliptical concave structure (3.2.2). The valve plate elliptical concave structure (3.2.2) is disposed on the side of the valve plate base (3.2.1) facing the fixed vortex exhaust port (1.2) of the fixed vortex (1). The semi-major axis a and semi-minor axis b of the elliptical concave structure (3.2.2) of the valve plate satisfy 1.2≤a / b≤1.6, the concavity depth h of the elliptical concave structure (3.2.2) of the valve plate is equal to the semi-major axis a, and the ratio of the concavity depth h to the diameter d of the fixed vortex exhaust port (1.2) satisfies 0.3≤h / d≤0.6; The thickness t of the valve plate substrate (3.2.1) and the valve plate elliptical concave structure (3.2.2) is consistent.

2. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The contour curve of the elliptical concave structure of the valve plate (3.2.2) satisfies the standard elliptical equation, and its major axis is consistent with the axial direction of the compressor exhaust port.

3. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The bottom of the valve plate elliptical concave structure (3.2.2) is a smooth curved surface with a radius of curvature R ≥ 2 mm.

4. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The thickness t of the exhaust valve plate (3.2) is 0.3mm~0.5mm.

5. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The ratio h / d of the concave depth h to the diameter d of the fixed vortex exhaust port (1.2) is 0.4~0.

5.

6. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The ratio of the semi-major axis a to the semi-minor axis b of the elliptical concave structure of the valve plate (3.2.2) is 1.

5.

7. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The exhaust valve limiter (3.1) is fixed to the fixed vortex (1) through the bolt hole (3.1.1), and the exhaust valve limiter (3.1) is provided with a vent hole (3.1.2).

8. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The contact surface of the exhaust valve limiter (3.1) toward the exhaust valve plate (3.2) is a concave surface that matches the elliptical concave structure (3.2.2) of the valve plate.

9. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The exhaust valve limiter (3.1) limits the maximum opening height of the exhaust valve disc (3.2) to 6 mm.

10. The scroll compressor noise reduction exhaust valve according to claim 1, characterized in that: The vent hole (3.1.2) on the exhaust valve limiter (3.1) has a diameter of 5mm.

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