Silencer of screw vacuum pump

Abstract

The utility model provides a screw vacuum pump silencer. An arranged silencing mechanism comprises a flow dispersing part for dispersing sound wave airflow, a first sound absorbing part for reducing noise through a shaft hole turbulent flow groove and a second sound absorbing part for absorbing sound and reducing noise through an airflow ramp. The problems that a silencer on a vacuum pump body is poor in silencing effect and noise leaks outwards are solved by introducing airflow carrying sound waves into the silencing shell embedded with the silencing mechanism for multi-stage noise reduction. And a purging device is arranged in the shaft hole of the first sound absorption part, so that the problem that holes in the silencer are blocked is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of air compressors, in particular to a screw vacuum pump muffler. Background Art

[0002] The screw vacuum pump has a high suction speed and a low ultimate pressure. It is a kind of pump equipment with a very wide range of applications for obtaining vacuum. However, when the screw vacuum pump is working, the high-pressure gas will make a lot of noise when it rubs against the pipe wall when it flows at high speed in the pipe. In order to reduce this noise, the most common practice is to install a muffler on the air compressor. However, due to the limitations of the existing technology, the existing mufflers still have many shortcomings. For example, the Chinese patent with publication number CN220249294U discloses a muffler for a vacuum press, which mainly opens a hole in the ventilation pipe in the pipe, so that the noise can be absorbed by the sound-absorbing material through the hole, thereby reducing the sound pressure inside the pipe. However, the problems such as the leakage noise outside the vacuum pump body and the blockage of the holes inside the muffler cannot be effectively solved. Utility Model Content

[0003] The utility model aims to provide a screw vacuum pump muffler to solve the problems of poor muffler effect, external leakage noise and blockage of internal holes of the muffler on the vacuum pump body.

[0004] In order to solve the above technical problems, the utility model provides a screw vacuum pump muffler, including a muffler shell with a muffler mechanism embedded therein, one end of the muffler shell is connected to an air inlet, and the other end is connected to an exhaust port, the muffler mechanism includes a flow-relief portion close to the air inlet, a first sound-absorbing portion in the middle, and a second sound-absorbing portion close to the exhaust port, the first sound-absorbing portion and the second sound-absorbing portion are separated by a predetermined distance;

[0005] An axial hole is arranged through the first sound absorbing part, and a turbulent flow groove is arranged around the inner wall of the axial hole;

[0006] The second sound absorbing part is made of sound absorbing material and is axially connected to the exhaust port through an air flow ramp that penetrates inside.

[0007] In a preferred embodiment: the diversion portion includes a radial ring fixedly connected in the silencer shell, an axial tube is inserted into the radial ring, a diversion plate is sealed at one end of the axial tube close to the air inlet, and the other end is close to the diversion component.

[0008] In a preferred embodiment: the diversion plate is provided with a plurality of diversion holes with different apertures.

[0009] In a preferred embodiment: the drainage assembly includes a conical drainage plug, a plug support, and an elastic member connecting the drainage plug and the plug support.

[0010] In a preferred embodiment: the plug support includes a support plate and a connecting rod, and the connecting rod is bolted to the support plate by penetrating mounting holes on the support plate and the radial ring.

[0011] In a preferred embodiment: the drainage plug is clearance-matched with the end of the shaft tube in the direction close to the end of the shaft tube, and its cone height is not less than 45 mm and the cone angle is not greater than 65°.

[0012] In a preferred embodiment: the turbulence groove is a V-shaped groove, and the reflection inclination angle of the V-shaped groove is not greater than 60°.

[0013] In a preferred embodiment: it also includes a purge device, the input end of the purge device is connected to an external air source, and the output end of the purge device is connected to the inner wall of the shaft hole.

[0014] In a preferred embodiment: the airflow ramp includes a first channel, a second channel and a third channel which are parallel to each other from bottom to top, and two ends of the second channel are respectively connected to the first channel and the third channel through angle bends;

[0015] The first channel and the third channel are equal in length and are arranged alternately.

[0016] In a preferred embodiment: the inner angle of the corner bend is not greater than 120°.

[0017] Compared with the prior art, the technical solution of the utility model has the following beneficial effects:

[0018] The utility model provides a screw vacuum pump muffler, whose muffler mechanism includes a flow-dispersing part for dispersing sound wave airflow, a first sound-absorbing part for reducing noise through a shaft hole turbulent groove, and a second sound-absorbing part for absorbing and reducing noise through a flow ramp. The utility model solves the problem of poor muffler effect and noise leakage of the muffler on the vacuum pump body by introducing the airflow carrying sound waves into a muffler shell embedded with a muffler mechanism for multi-stage muffler; a purge device is arranged in the shaft hole of the first sound-absorbing part to overcome the problem of blockage of the internal holes of the muffler. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the appearance of an embodiment of the utility model;

[0020] Figure 2 It is a perspective view of the internal structure of an embodiment of the utility model;

[0021] Figure 3 This is a schematic diagram of the drainage portion of an embodiment of the utility model from a first viewing angle;

[0022] Figure 4 2 is a schematic diagram of the drainage portion of the embodiment of the utility model from a second viewing angle;

[0023] Figure 5This is a large sample diagram of the diversion plate of the utility model embodiment;

[0024] Figure 6 is a side view of the first sound absorbing part of the embodiment of the utility model;

[0025] Figure 7 is a radial cross-sectional view of the first sound absorbing portion of an embodiment of the utility model;

[0026] Figure 8 It is a radial cross-sectional view of the second sound absorbing part of the embodiment of the utility model. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model; it is obvious that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the utility model without making creative work are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "installed / connected", "connected", etc. should be understood in a broad sense. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0030] refer to Figure 1-8The present embodiment provides a screw vacuum pump muffler, which comprises a muffler shell 1 used as a pressure vessel. One end of the muffler shell 1 is connected to the air inlet 11, and the other end is connected to the exhaust port 12, and a muffler mechanism is embedded in the interior of the muffler shell 1. The muffler mechanism comprises a diversion portion 13 close to the air inlet 11, a first sound absorbing portion 14 in the middle, and a second sound absorbing portion 15 abutting the exhaust port 12. The first sound absorbing portion 14 is arranged at a predetermined distance from the diversion portion 13 to ensure that the sound wave airflow entering from the air inlet 11 can be more efficiently dispersed to the surroundings during the process of being transmitted from the diversion portion 13 to the first sound absorbing portion 14, and can enter each axial hole 141 of the first sound absorbing portion 14 more evenly.

[0031] From the perspective of structural details, the flow-discharging portion 13 is composed of a radial ring 131, an axial tube 132, a flow-discharging plate 133 and a flow-discharging assembly 134. The radial ring 131 is fixedly connected to the radial surface of the inner wall of the silencer shell 1 close to the air inlet 11. The radial ring 131 is axially connected to an axial tube 132. The end of the axial tube 132 close to the air inlet 11 is sealed with a flow-discharging plate 133, and the other end thereof is gap-matched with a flow-discharging plug 1341 on the flow-discharging assembly 134. Since the flow-discharging plate 133 is provided with a plurality of flow-discharging holes of different apertures, and the flow-discharging holes are of different sizes, the sound wave airflow can be preliminarily disturbed. The flow-discharging plug 1341, which is gap-matched with the axial tube 132, is conical, and its cone tip is arranged toward the end opening direction close to the axial tube 132. Under the parameter setting of ensuring that the cone height of the drainage plug 1341 is not less than 45mm and the cone angle is not greater than 65, in addition to being able to better disperse the sound wave airflow flowing through the shaft tube 132 to the first sound absorbing part 14, the elastic member 1342 connecting the drainage plug 1341 and the plug support can take into account the matching strength of the drainage component 134 while also taking into account the stability of the drainage component 134. In other words, since the plug support includes a support plate 1343 and a connecting rod 1344, the connecting rod 1344 is bolted to the support plate 1343 by penetrating the mounting holes on the support plate 1343 and the radial ring. The support plate 1343 is firmly fixed on a radial ring fixed to the inner wall of the silencer shell to ensure that the support plate 1343 can provide a relatively stable force support when serving as a base for supporting the drainage plug 1341 and the elastic member 1342. After the drainage plug 1341 is impacted by the airflow, the load is transferred to the elastic member 1342. The elastic member 1342 is compressed to accumulate elastic restoring force and transfer the excess impact force to the support plate 1343.

[0032] The sound wave airflow is divided and diverged through the diversion part 13 and then reaches the first sound absorbing part 14. Figure 6 As shown, a plurality of axial holes 141 are arranged through the first sound absorbing part 14, and a turbulent flow groove is arranged around the inner wall of the axial hole 141. The radial section of the first sound absorbing part 14 is shown as follows Figure 7As shown, the cross-sectional shape of the turbulent groove is V-shaped, and the wall reflection inclination angle a1 of the V-shaped groove is not greater than 60°. When the sound wave airflow passes through this channel, it is reflected by the continuous V-shaped grooves to form turbulence, which is used to further weaken the energy propagation of the noise wave.

[0033] However, although the V-shaped groove arranged around the shaft hole 141 has the function of making the noise waves flowing through it form turbulence to weaken the energy of the noise waves, due to the long-term high-frequency flow of the sound wave airflow through the shaft hole 141 and rubbing the wall surface of the hole, the electrostatic adsorption effect generated by the friction makes some micro-particles such as dust and hair carried in the airflow accumulate more and more in the V-shaped groove. In addition, the structure of the V-shaped groove can better preserve the particulate matter in the extracted gas, which will inevitably affect the silencing effect over time. In view of this, the utility model solves the problem of blockage of the shaft hole 141 on the muffler by providing a purge device connected to the V-shaped groove. The input end of the purge device 142 is connected to the external air source by connecting the external air source inlet pipe 143 on the muffler shell 1, and its output end is connected to the shaft hole 141. The purge device 142 transports the connected external air source airflow to the V-shaped grooves of each shaft hole through the purge pipeline, and purges in time when the shaft hole 141 is found to be blocked to ensure the silencing effect of the muffler component.

[0034] After the sonic airflow flows through the first sound absorbing part 14, part of the noise is reflected and eliminated by the V-shaped groove of the turbulent groove, while part of the sonic airflow that is not eliminated comes to the cavity formed by the interval between the first sound absorbing part 14 and the second sound absorbing part 15. As the continuous sonic airflow gathers at this position, the pressure in the cavity also increases. Obviously, when the high-pressure gas surges at high speed in the cavity, it will continue to generate noise due to friction with the surrounding cavity walls. In order to solve the problem of noise source overflow caused by the failure of the first sound absorbing part 14 to completely eliminate noise, at the same time, the performance requirement of connecting the airflow channel in the silencer shell 1 to output it to the outside is also taken into consideration. In the present invention, the second sound absorbing part 15 pressed against the exhaust port 12 is configured as a fitting made of sound absorbing material. When the sound wave airflow collides and squeezes the second sound absorbing part 15, most of the noise sound waves will be absorbed by the sound absorbing material, and a small part of the noise sound waves will be squeezed into the airflow ramp 151 that runs through the second sound absorbing part 15 along with the surging airflow, and continue to consume energy after two turns and collisions in the ramp 151, and finally reach the exhaust port 102.

[0035] Specifically, the internal airflow ramp of the second sound absorbing portion 105 is in an 'S' shape, such as Figure 8As shown, its linear composition includes a first channel 1513, a second channel 1512 and a third channel 1511 which are parallel to each other from bottom to top. From the perspective of spatial position, the first channel 1513 and the third channel 1511 at the upper and lower positions are of equal length and are arranged in a staggered manner front to back. The second channel 1512 located in the middle position is shorter than the first channel, and its two ends are connected to the first channel 1513 and the third channel 1511 respectively through angle bends, and the inner angle a2 of the angle bend is not greater than 120°. Through experimental simulation data analysis, it is concluded that when the inner angle a2 of the angle bend is close to 120°, the sound wave airflow can be made to dissipate energy through secondary impact in the airflow ramp 151 of the second sound absorbing part 15 to weaken the noise sound wave, and the sound wave airflow can also pass through the airflow channel more evenly. And the wall surface of the airflow ramp 151 is made of sound-absorbing material, which can absorb noise waves to the greatest extent and achieve the best noise reduction effect.

[0036] The above is only a preferred specific implementation method of the utility model, but the design concept of the utility model is not limited to this. Any technician familiar with the technical field who uses this concept to make non-substantial changes to the utility model within the technical scope disclosed by the utility model shall be deemed to infringe the protection scope of the utility model.

Claims

1. A screw vacuum pump muffler, comprising a muffler shell with a muffler mechanism embedded therein, one end of the muffler shell being connected to an air inlet and the other end being connected to an exhaust port, characterized in that: The muffler mechanism comprises a flow-relief portion close to the air inlet, a first sound-absorbing portion in the middle, and a second sound-absorbing portion close to the air outlet, wherein the first sound-absorbing portion is spaced a predetermined distance from the second sound-absorbing portion; An axial hole is arranged through the first sound absorbing part, and a turbulent flow groove is arranged around the inner wall of the axial hole; The second sound absorbing part is made of sound absorbing material and is axially connected to the exhaust port through an air flow ramp that penetrates inside.

2. A screw vacuum pump muffler according to claim 1, characterized in that: The diversion part comprises a radial ring fixed in the muffler shell, an axial tube is inserted into the radial ring, a diversion plate is sealed at one end of the axial tube close to the air inlet, and the other end of the axial tube is close to the diversion assembly.

3. A screw vacuum pump muffler according to claim 2, characterized in that: The diversion plate is provided with a plurality of diversion holes with different apertures.

4. A screw vacuum pump muffler according to claim 2, characterized in that: The drainage assembly comprises a conical drainage plug, a plug support, and an elastic member connecting the drainage plug and the plug support.

5. A screw vacuum pump muffler according to claim 4, characterized in that: The plug support comprises a supporting plate and a connecting rod, and the connecting rod is bolted to the supporting plate by penetrating mounting holes on the supporting plate and the radial ring.

6. A screw vacuum pump muffler according to claim 4, characterized in that: The drainage plug is clearance-matched with the end of the shaft tube in the direction close to the end of the shaft tube, and its cone height is not less than 45 mm and the cone angle is not greater than 65°.

7. The screw vacuum pump muffler according to claim 1, characterized in that: The turbulence groove is a V-shaped groove, and the reflection inclination angle of the V-shaped groove is not greater than 60°.

8. The screw vacuum pump muffler according to claim 1, characterized in that: It also includes a purge device, the input end of which is connected to an external air source, and the output end of which is connected to the inner wall of the shaft hole.

9. The screw vacuum pump muffler according to claim 1, characterized in that: The airflow ramp comprises a first channel, a second channel and a third channel which are parallel to each other from bottom to top, and two ends of the second channel are respectively connected to the first channel and the third channel through angle bends; The first channel and the third channel are equal in length and are arranged alternately.

10. A screw vacuum pump muffler according to claim 9, characterized in that: The inner angle of the corner bend is not greater than 120°.

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