Noise reduction structure of silencer of refrigeration compressor

Abstract

The noise reduction structure comprises a main shell and an upper cover connected to the main shell, a partition plate assembly is arranged in the main shell, an inner cavity of the silencer is divided into an upper cavity and a lower cavity, a noise elimination pipeline is formed on the partition plate assembly, a flow guide pipe is arranged at the top of the upper cavity, and the flow guide pipe is communicated with the upper cavity. And the air inlet at the lower end of the flow guide pipe is a big-end-down horn mouth. The internal pipeline structure of the silencer is further optimized and improved, so that the overall noise reduction function of the silencer is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration compressor manufacturing, in particular to a noise reduction structure of a refrigeration compressor muffler. Background Art

[0002] With the progress of society, people's living standards are constantly improving, and their sensory requirements are constantly improving. Among them, noise is one of the reasons that affect the quality of life. In the field of refrigeration compressors, noise has also become one of the important indicators to measure the quality of refrigeration compressors. The noise of the compressor is mainly composed of three parts: airflow pulsation noise, mechanical noise and electromagnetic noise. Among them, airflow pulsation noise is the main sound source affecting the noise of the compressor. Therefore, in order to reduce the airflow pulsation noise inside the compressor, a method of setting an air suction muffler at the suction end of the compressor is usually adopted to reduce the noise. The compressor suction muffler currently used is a resistive expansion muffler. The expansion muffler causes impedance changes during sound propagation through a sudden change in the cross-section of the internal pipe or a side-connected resonance cavity, etc., which produces reflection and interference of sound energy, thereby reducing the sound energy radiated outward by the muffler, thereby achieving the purpose of silencer. The present application further optimizes and improves the internal piping structure of the suction muffler, which can effectively improve the noise reduction function of the suction muffler. The Chinese patent document with a publication date of October 14, 2022 and a publication number of CN217582433U discloses a noise-reducing suction silencer, including a protective frame and a silencer mechanism, the front and back sides of the protective frame are penetrated with heat dissipation holes, the left and right sides of the protective frame are fixedly installed with mounting blocks, the upper end of the protective frame is provided with an air inlet pipe, the lower end of the protective frame is provided with an air outlet pipe, the silencer mechanism is arranged inside the protective frame, and one end of the air inlet pipe is provided with an adsorption mechanism. By setting the silencer mechanism, align the threaded hole on the sealing cover with the threaded hole on the outer shell, and then tighten the bolts, insert the lower end of the air inlet pipe into the air inlet, and the airflow enters the silencer cavity inside the inner shell from the air inlet pipe. The silencer cotton on the outer shell can eliminate the residual sound, and then the airflow goes out from the air outlet pipe. The heat dissipation holes on the protective frame can prevent the internal temperature from being too high. The suction silencer adopts an additional protective frame and silencer cotton to eliminate the residual sound, which significantly increases the volume of the suction silencer. Utility Model Content

[0003] The utility model provides a noise reduction structure for a refrigeration compressor muffler, which further optimizes and improves the internal piping structure of the suction muffler, can effectively improve the noise reduction function of the suction muffler, and has lower mechanical noise compared with the existing structure.

[0004] The technical solution adopted by the utility model to solve the above technical problems is a noise reduction structure of a refrigeration compressor muffler, the refrigeration compressor muffler includes a main shell and an upper cover connected to the main shell, a partition assembly is arranged in the main shell, the inner cavity of the muffler is divided into an upper cavity and a lower cavity, a muffler pipe is formed on the partition assembly, a guide pipe is arranged on the top of the upper cavity, and the air inlet at the lower end of the guide pipe is a bell mouth with a small upper part and a large lower part. The utility model improves the currently commonly used structure that causes the change of impedance in the sound propagation process through the sudden change of the internal pipe section to produce the reflection and interference of the sound energy, thereby reducing the sound energy radiated outward from the muffler, and adopts a bell mouth structure with a small upper part and a large lower part at the air inlet at the lower end of the guide pipe, that is, the sudden change of the internal pipe section is appropriately transitionally processed, which can effectively reduce the airflow pulsation noise of the compressor in a specific frequency band, thereby improving the frequency-noise characteristics of the muffler as a whole, reducing the noise of the compressor without increasing the cost, and improving the performance of the compressor.

[0005] Preferably, the partition assembly is composed of a first partition and a second partition arranged oppositely, a transverse partition is arranged on the upper part of the partition assembly, the upper part of the transverse partition constitutes the upper chamber, and the lower part of the transverse partition constitutes the lower chamber. The partition assembly is composed of a first partition and a second partition arranged oppositely, so as to form a muffler pipe on the partition assembly, and the first partition and the second partition are assembled and placed in the main shell for easy assembly.

[0006] Preferably, a longitudinal partition is vertically arranged below the transverse partition, and the longitudinal partition divides the lower chamber into a left lower chamber and a right lower chamber. The multi-chamber structure is conducive to reducing the sound energy radiated outward by the muffler and reducing the noise of the compressor.

[0007] Preferably, the muffler pipe includes an upper muffler pipe and a lower muffler pipe, one end of the lower muffler pipe is connected to the air inlet of the muffler, and the other end passes through the longitudinal partition plate and is opposite to the lower end of the upper muffler pipe, and the upper end of the upper muffler pipe is located below the bell mouth. The change of impedance during sound propagation caused by the sudden change of the cross section of the internal pipe generates reflection and interference of sound energy, thereby reducing the sound energy radiated outward from the muffler, thereby achieving the purpose of muffler.

[0008] Preferably, the muffler pipe is composed of two semicircular grooves arranged oppositely on the first partition plate and the second partition plate. The two semicircular grooves are assembled to form a complete muffler pipe.

[0009] Preferably, the lower muffler is in a Z-shape, the upper muffler is vertically arranged, the inner diameter of the upper muffler is larger than the inner diameter of the lower muffler, and the upper end of the upper muffler is located above the diaphragm. The tortuous path of the muffler is conducive to further reducing noise.

[0010] Preferably, the flow guide pipe is a round pipe, and a panel is provided at the outer periphery of the bottom of the bell mouth of the upper cover, and the outlet at the upper end of the upper muffler pipe is opposite to the panel and its extension line is located inside the panel. A panel with a larger opening is provided at the outer periphery of the bottom of the bell mouth, and the outlet at the upper end of the muffler pipe points to the enclosed area of ​​the panel and leaves a gap with the edge of the panel, which is conducive to further reducing noise.

[0011] Preferably, the longitudinal section of the side wall of the bell mouth is in an arc shape, and the radius of curvature of the arc shape is 2 to 5 mm. The longitudinal section of the side wall of the bell mouth is in an arc shape (equivalent to the rounded corners at the mutation point), that is, the mutation point of the pipe cross section at the inlet of the guide pipe is rounded, which can effectively reduce the airflow pulsation noise in a specific frequency band of the compressor, and can improve the frequency-noise characteristics of the muffler as a whole, and enhance the noise reduction performance of the muffler. If the radius of curvature of the arc is too large, it will affect the noise reduction effect caused by the mutation of the pipe cross section, and if the radius of curvature of the arc is too small, the improvement of the airflow pulsation noise in certain specific frequency bands is not significant. Experiments have shown that the radius of curvature of the arc shape is 2 to 5 mm, which is the best range.

[0012] As another optional solution, the side wall of the bell mouth is a conical surface, the cone vertex angle of the conical surface is 75-105 degrees, and the extension length of the conical surface is 2-5 mm. The difference between this solution and the previous solution is that the rounded corners at the mutation point are changed to beveled, that is, the mutation point of the pipe section adopts a bevel transition connection, which also has the effect of improving the frequency-noise characteristics of the muffler as a whole and enhancing the noise reduction performance of the muffler.

[0013] The beneficial effect of the utility model is that the utility model effectively improves the overall noise reduction function of the muffler by further optimizing and improving the internal piping structure of the muffler. Compared with the existing structure, it has lower mechanical noise, reduces the noise of the compressor without increasing the cost, and improves the performance of the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural cross-sectional view of the utility model refrigeration compressor muffler;

[0015] Figure 2 This is another structural sectional view of the refrigeration compressor muffler of the utility model;

[0016] Figure 3 This is a structural cross-sectional view of the upper cover of Example 1 of the utility model;

[0017] Figure 4 This is a structural cross-sectional view of the upper cover of Example 2 of the utility model;

[0018] Figure 5 The utility model is a schematic diagram of the appearance structure of a refrigeration compressor muffler.

[0019] In the figure: 1. main shell, 2. upper cover, 3. upper cavity, 4. guide pipe, 5. air inlet, 6. first partition, 7. second partition, 8. transverse partition, 9. longitudinal partition, 10. lower left cavity, 11. lower right cavity, 12. upper muffler, 13. lower muffler, 14. air intake, 15. enclosure, 16. upper port, 17. partition. DETAILED DESCRIPTION

[0020] The specific implementation of the technical solution of the utility model is further described below through examples and in conjunction with the accompanying drawings.

[0021] Example 1

[0022] exist Figure 1 Figure 2 In the embodiment 1 shown, a noise reduction structure of a refrigeration compressor muffler is provided. The refrigeration compressor muffler comprises a main housing 1 and an upper cover 2 (see FIG. Figure 5 ), the upper cover is provided with a mounting slot, and the main shell is provided with a positioning slot that matches the upper cover, and the two are positioned and fixedly connected by plugging; the main shell is provided with a partition assembly inside, and the partition assembly is composed of a first partition 6 and a second partition 7 that are arranged oppositely, and the convex part of one side of the second partition is embedded in the mounting slot of the first partition through the mounting slot arranged on the first partition to realize the connection and combination, and the partition assembly is composed of a first partition and a second partition that are arranged oppositely, so as to facilitate the formation of a muffler pipe on the partition assembly, and the first partition and the second partition are put into the main shell after being assembled, so as to facilitate the assembly of the refrigeration compressor muffler. The upper part of the partition assembly is provided with a horizontally arranged transverse partition 8, and the transverse partition divides the inner cavity of the muffler into two cavities, an upper cavity 3 and a lower cavity. The cavity above the transverse partition constitutes the upper cavity 3 of the refrigeration compressor muffler, and the lower part of the transverse partition constitutes the lower cavity of the refrigeration compressor muffler; a guide pipe 4 is arranged on the top of the upper cavity, and the guide pipe of this embodiment is a circular pipe, and the air inlet 5 at the lower end of the guide pipe located at the upper cavity is a trumpet mouth that is small on the upper side and large on the lower side. A longitudinal partition 9 is also vertically provided below the transverse partition, which divides the lower cavity into a left lower cavity 10 and a right lower cavity 11, wherein the left lower cavity is located on the side close to the air suction port 14 of the refrigeration compressor muffler, and the right lower cavity is located on the side away from the air suction port 14 of the refrigeration compressor muffler. The multi-cavity structure of the refrigeration compressor muffler of the utility model is beneficial to reducing the sound energy radiated outward by the refrigeration compressor muffler, thereby reducing the noise of the refrigeration compressor.

[0023] After the first partition and the second partition are combined, a muffler pipe is formed on the partition assembly. The muffler pipe of this embodiment is composed of two semicircular grooves arranged relatively on the first partition and the second partition. The muffler pipe of this embodiment includes an upper muffler pipe 12 and a lower muffler pipe 13. The lower muffler pipe is in a Z-shape as a whole. One end of the lower muffler pipe is connected to the air inlet 14 outside the main shell of the muffler, and the other end extends into the main shell, bends downward, and then extends horizontally inward. After passing through the longitudinal partition, its end is upward, and the end of the lower muffler pipe is spaced opposite to the lower port of the upper muffler pipe. There is a gap 17 between the two pipe openings. The width of the gap 17 between the upper and lower mufflers of this embodiment is 12 mm. The upper muffler pipe is arranged vertically as a whole, and the upper end of the upper muffler pipe is located in the upper cavity. The upper end of the upper muffler pipe of this embodiment is offset to the side close to the air inlet and passes through the transverse partition. Its upper end is located above the transverse partition and its port is located below the bell mouth. The inner diameter of the upper muffler is larger than that of the lower muffler, and the inner diameter of the upper muffler located in the upper cavity is smaller than that of the upper muffler located in the lower cavity. In this embodiment, the inner diameter of the upper muffler located in the lower cavity is 8 mm, the inner diameter of the upper muffler located in the upper cavity is 5 mm, and the inner diameter of the lower muffler is 4 mm. A panel 15 is provided at the outer periphery of the bottom of the bell mouth of the upper cover, and the upper port 16 of the upper muffler is opposite to the panel and its extension line is located in the panel. The panel of this embodiment is circular, and the diameter of the enclosed portion is 22 mm. The width of the gap between the upper port of the upper muffler and the edge of the panel is 2.2 mm.

[0024] The longitudinal section of the side wall of the bell mouth of this embodiment is an arc shape (see Figure 3 ), the radius of curvature of the arc is usually 2 to 5 mm, that is, the inverted radius R of the sudden change of the air inlet at the lower end of the guide tube (see Figure 3 ) has a fillet of 2 to 5 mm; the R value of this embodiment is 3 mm, and the actual measured noise values ​​of the same compressor with an R value of 0-8 mm in the experiment are: R=0 (equivalent to the mutation point not being improved to a right angle), noise 47.65 decibels; R=1mm, noise 47.25 decibels; R=2mm, noise 46.33 decibels; R=3mm, noise 45.48 decibels; R=4mm, noise 45.85 decibels; R=5mm, noise 46.14 decibels; R=6mm, noise 46.38 decibels; R=7mm, noise 46.44 decibels; R=8mm, noise 46.42 decibels; It can be seen that the noise is smaller when the R value is 3 mm.

[0025] Example 2

[0026] The refrigeration compressor silencer of Example 2 includes a main shell 1 and an upper cover 2 snapped onto the main shell, the upper cover is provided with an installation slot, and the main shell is provided with a positioning slot matching the upper cover, and the two are positioned and fixedly connected by plugging; a partition assembly is provided inside the main shell, and the partition assembly is composed of a first partition 6 and a second partition 7 that are relatively arranged and connected in a docking combination, and the raised portion of one side of the second partition is embedded in the mounting groove of the first partition through the mounting groove provided on the first partition to realize the connection and combination, and the partition assembly is composed of a first partition and a second partition that are relatively arranged to facilitate the formation of a silencer pipe on the partition assembly, and the first partition and the second partition are assembled and placed in the main shell, which is convenient for assembling the refrigeration compressor silencer. A horizontally arranged transverse partition 8 is provided at the upper part of the partition assembly, and the transverse partition divides the inner cavity of the muffler into two cavities, an upper cavity 3 and a lower cavity. The cavity above the transverse partition constitutes the upper cavity 3 of the refrigeration compressor muffler, and the lower part of the transverse partition constitutes the lower cavity of the refrigeration compressor muffler; a guide tube 4 is provided at the top of the upper cavity, and the guide tube of this embodiment is a circular tube, and the air inlet 5 at the lower end of the guide tube at the upper cavity is a trumpet mouth with a small upper part and a large lower part. A longitudinal partition 9 is also vertically provided below the transverse partition, and the longitudinal partition divides the lower cavity into a left lower cavity 10 and a right lower cavity 11, wherein the left lower cavity is located on the side close to the air inlet 14 of the refrigeration compressor muffler, and the right lower cavity is located on the side away from the air inlet 14 of the refrigeration compressor muffler. The multi-cavity structure of the refrigeration compressor muffler of the utility model is conducive to reducing the sound energy radiated outward by the refrigeration compressor muffler, thereby reducing the noise of the refrigeration compressor.

[0027] After the first partition and the second partition are combined, a muffler pipe is formed on the partition assembly. The muffler pipe of this embodiment is composed of two semicircular grooves arranged relatively on the first partition and the second partition. The muffler pipe of this embodiment includes an upper muffler pipe 12 and a lower muffler pipe 13. The lower muffler pipe is in a Z-shape as a whole. One end of the lower muffler pipe is connected to the air inlet 14 outside the main shell of the muffler, and the other end extends into the main shell, bends downward, and then extends horizontally inward. After passing through the longitudinal partition, its end is upward, and the end of the lower muffler pipe is spaced opposite to the lower port of the upper muffler pipe. There is a gap 17 between the two pipe openings. The width of the gap 17 between the upper and lower mufflers of this embodiment is 12 mm. The upper muffler pipe is arranged vertically as a whole, and the upper end of the upper muffler pipe is located in the upper cavity. The upper end of the upper muffler pipe of this embodiment is offset to the side close to the air inlet and passes through the transverse partition. Its upper end is located above the transverse partition and its port is located below the bell mouth. The inner diameter of the upper muffler is larger than that of the lower muffler, and the inner diameter of the upper muffler located in the upper cavity is smaller than that of the upper muffler located in the lower cavity. In this embodiment, the inner diameter of the upper muffler located in the lower cavity is 7 mm, the inner diameter of the upper muffler located in the upper cavity is 4 mm, and the inner diameter of the lower muffler is 4 mm. A shroud 15 is provided at the outer periphery of the bottom of the bell mouth of the upper cover, and the upper port 16 of the upper muffler is opposite to the shroud and its extension line is located in the shroud. The shroud of this embodiment is circular, and the diameter of the enclosed part is 18 mm. The width of the gap between the upper port of the upper muffler and the edge of the shroud is 1.8 mm.

[0028] Embodiment 2 The side wall of the bell mouth is a conical surface (see Figure 4 ), the cone vertex angle of the conical surface is usually 75-105 degrees, and the extension length of the conical surface (i.e., the length of the hypotenuse of the longitudinal section) is 2-5 mm. In this embodiment, the cone vertex angle of the conical surface is 90 degrees, and the extension length of the conical surface is 3 mm (i.e., the air inlet at the lower end of the guide tube suddenly changes at an angle of 45 degrees, and the length of the hypotenuse L is 3 mm (see Figure 4 ). The air inlet mutation point at the lower end of the guide tube of this embodiment adopts chamfer (conical surface) transition, and its noise reduction effect is similar to the rounded corner of Example 1. Experiments have shown that when the air inlet mutation point at the lower end of the guide tube is chamfered at a 45-degree angle and the hypotenuse length is 3 mm, the noise is low, which is 45.78 decibels, but slightly higher than the lowest value of Example 1. The test data of other angles and hypotenuse lengths are all inferior to 45.78 decibels, which will not be listed here one by one.

[0029] The utility model improves the currently commonly used structural form in which a sudden change in the cross section of an internal pipe causes a change in impedance during sound propagation to produce reflection and interference of sound energy, thereby reducing the sound energy radiated outward from the muffler. A trumpet-mouth structure with a small top and a large bottom is adopted at the air inlet at the lower end of the guide pipe, that is, a suitable smooth transition treatment is performed on the sudden change in the cross section of the internal pipe, and further improvements are made to the structure such as the sudden change in the cross section of the internal pipe, which can effectively reduce the airflow pulsation noise in a specific frequency band of the compressor, thereby improving the frequency-noise characteristics of the muffler as a whole, reducing the noise of the compressor without increasing the cost, and improving the performance of the compressor.

[0030] In addition to the above-mentioned embodiments, within the scope disclosed in the claims and the specification of the utility model, the technical features or technical data of the utility model can be reselected and combined to form new embodiments, which can be achieved by those skilled in the art without creative work. Therefore, these embodiments that are not described in detail in the utility model should also be regarded as specific embodiments of the utility model and within the protection scope of the utility model.

Claims

1. A noise reduction structure for a refrigeration compressor muffler, characterized in that: The refrigeration compressor muffler comprises a main shell (1) and an upper cover (2) connected to the main shell, a partition assembly is provided in the main shell, the inner cavity of the muffler is divided into an upper cavity (3) and a lower cavity, a muffler pipe is formed on the partition assembly, a guide pipe (4) is provided at the top of the upper cavity, and an air inlet (5) at the lower end of the guide pipe is a bell mouth with a small upper portion and a large lower portion.

2. The noise reduction structure of the refrigeration compressor muffler according to claim 1, characterized in that: The partition assembly is composed of a first partition (6) and a second partition (7) arranged opposite to each other. A transverse partition (8) is provided on the upper part of the partition assembly. The upper part of the transverse partition forms the upper chamber, and the lower part of the transverse partition forms the lower chamber.

3. The noise reduction structure of the refrigeration compressor muffler according to claim 2, characterized in that: A longitudinal partition (9) is vertically arranged below the transverse partition, and the longitudinal partition divides the lower chamber into a left lower chamber (10) and a right lower chamber (11).

4. The noise reduction structure of the refrigeration compressor muffler according to claim 2, characterized in that: The muffler pipe comprises an upper muffler pipe (12) and a lower muffler pipe (13); one end of the lower muffler pipe is connected to the air intake port (14) of the muffler, and the other end passes through the longitudinal partition plate and is opposite to the lower end of the upper muffler pipe; the upper end of the upper muffler pipe is located below the bell mouth.

5. The noise reduction structure of the refrigeration compressor muffler according to claim 2, characterized in that: The muffler pipe is composed of two semicircular grooves arranged oppositely on the first partition plate and the second partition plate.

6. The noise reduction structure of the refrigeration compressor muffler according to claim 4, characterized in that: The lower muffler is in a Z-shape as a whole, and the upper muffler is vertically arranged as a whole. The inner diameter of the upper muffler is larger than the inner diameter of the lower muffler, and the upper end of the upper muffler is located above the transverse partition.

7. The noise reduction structure of the refrigeration compressor muffler according to claim 4, characterized in that: The guide pipe is a circular pipe, and a panel (15) is provided on the outer periphery of the bottom of the bell mouth of the upper cover. The upper port (16) of the upper muffler pipe is opposite to the panel and its extension line is located inside the panel.

8. The noise reduction structure of a refrigeration compressor muffler according to any one of claims 1 to 7, characterized in that: The longitudinal section of the side wall of the bell mouth is in an arc shape, and the curvature radius of the arc is 2 to 5 mm.

9. The noise reduction structure of a refrigeration compressor muffler according to any one of claims 1 to 7, characterized in that: The side wall of the bell mouth is a conical surface, the cone apex angle of the conical surface is 75-105 degrees, and the extension length of the conical surface is 2-5 mm.

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