A dry vacuum pump silencing device and a dry vacuum pump unit having the same

Abstract

The present invention relates to the technical field of vacuum pump noise reduction, and particularly relates to a dry vacuum pump noise reduction device and a dry vacuum pump unit having the same. The dry vacuum pump noise reduction device includes: a noise reduction housing with a noise reduction cavity provided inside; a hollow inner core installed in the noise reduction cavity, at least one layer of support partition is connected to the outer wall of the hollow inner core, an air passage gap is reserved between the support partition and the inner wall of the noise reduction cavity, and air holes are penetrated through the side wall of the hollow inner core; a check member installed on one side of the noise reduction cavity close to the air inlet of the noise reduction housing, and the outer wall of the check member is adapted to be in close contact with the air inlet. When in use, the dry vacuum pump noise reduction device is installed at the exhaust port of the dry vacuum pump, and the air flow enters the noise reduction housing. The air flow repeatedly passes through the support partition and the air holes, continuously enters and exits the hollow inner core and collides, so that the original sound energy of the air flow is greatly attenuated and the audio frequency is changed, and the noise in each frequency band generated during the operation of the vacuum pump can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum pump noise reduction, and particularly relates to a dry vacuum pump noise reduction device and a dry vacuum pump unit having the same. Background Art

[0002] A vacuum pump is a device that uses mechanical, physical, chemical, physicochemical and other methods to evacuate a container to obtain and maintain a vacuum, so as to meet the usage requirements of vacuum evaporation, vacuum concentration, vacuum rewetting, vacuum impregnation, vacuum drying, vacuum smelting, etc. There are many types of vacuum pumps, such as liquid ring vacuum pumps, oil sealed pumps, dry vacuum pumps, water jet vacuum pumps, etc. Since the dry vacuum pump has no working fluid in the working volume, it not only enhances the reliability of the pump, but is also more durable, less polluting, and has higher overall performance. During the vacuum pumping process of the dry vacuum pump, when the pumping reaches the ultimate pressure of the device, non-mechanical movement noise will be generated, causing noise pollution in the working environment.

[0003] In the prior art, the dry vacuum pump is provided with an inner tube and an outer tube which are sleeved inside and outside, and sound-absorbing cotton is arranged between the inner tube and the outer tube to reduce the noise generated by the dry vacuum pump during operation. However, due to the loose texture of the sound-absorbing cotton, it can only eliminate high-frequency noise, and its ability to reduce medium and low-frequency noise is weak, resulting in the dry vacuum pump still emitting relatively high noise during operation, affecting the normal work of the staff in the environment. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the noise reduction ability of the dry vacuum pump in the prior art is limited, so as to provide a dry vacuum pump noise reduction device and a dry vacuum pump unit having the same.

[0005] To solve the above technical problem, the present invention provides a dry vacuum pump noise reduction device, including:

[0006] A noise reduction housing, inside which a noise reduction cavity is provided;

[0007] A hollow inner core, installed in the noise reduction cavity, at least one layer of support partition is connected to the outer wall of the hollow inner core, a gas passing gap is reserved between the support partition and the inner wall of the noise reduction cavity, and gas passing holes are provided through the side wall of the hollow inner core;

[0008] A check member, installed on the side of the noise reduction cavity close to the air inlet of the noise reduction housing, the outer wall of the check member is adapted to fit and abut against the air inlet, the check member has a first state in which it abuts against the air inlet under its own gravity to block the air inlet, and a second state in which it separates from the air inlet under the action of air flow to allow gas to enter the noise reduction cavity.

[0009] Optionally, the outer edge of the support partition is fitted with the inner wall of the noise reduction cavity, and auxiliary air holes are provided through the support partition.

[0010] Optionally, an elastic member is installed between the hollow inner core and the air outlet end of the muffler cavity. The elastic member is in a compressed state to apply a biasing force to the hollow inner core in a direction away from the air outlet end.

[0011] Optionally, a conical section is provided at the air inlet end of the muffler cavity, and the check member is installed in the conical section.

[0012] Optionally, the check member is spherical, conical or frustum-shaped.

[0013] Optionally, the muffler housing includes a housing body and an end cover. The end cover is detachably installed at the air outlet end of the housing body, and an air outlet is provided on the end cover.

[0014] Optionally, a sealing assembly is installed between the housing body and the end cover.

[0015] Optionally, an installation groove is provided on the side wall of the end cover, and at least part of the sealing assembly is installed in the installation groove.

[0016] Optionally, the plurality of air passing holes have various pore diameters.

[0017] The present invention also provides a dry vacuum pump unit having the dry vacuum pump muffling device described in the present invention.

[0018] The technical solution of the present invention has the following advantages:

[0019] 1. The dry vacuum pump muffling device provided by the present invention includes: a muffler housing having a muffler cavity provided therein; a hollow inner core installed in the muffler cavity, with at least one layer of support partition connected to the outer wall of the hollow inner core, a gas passing gap reserved between the support partition and the inner wall of the muffler cavity, and air passing holes penetrating through the side wall of the hollow inner core; a check member installed on the side of the muffler cavity close to the air inlet of the muffler housing, the outer wall of the check member being adapted to fit and abut against the air inlet, the check member having a first state in which it abuts against the air inlet under its own gravity to block the air inlet, and a second state in which it separates from the air inlet under the action of air flow to allow gas to enter the muffler cavity.

[0020] When in use, the noise reduction device of the dry vacuum pump is installed at the exhaust port of the dry vacuum pump, ensuring that the air inlet of the noise reduction housing is arranged downward, so that the check member fits and seals with the air inlet under its own gravity, blocking the air inlet. When the dry vacuum pump is working, it causes the air flow to vibrate and generate noise. The air flow discharged by the vacuum pump passes through the air inlet of the noise reduction housing, and the air flow impacts the check member that abuts and seals with the air inlet, causing the check member to separate from the air inlet, and the air flow enters the noise reduction housing. The air flow repeatedly passes through the support partition and the air passing holes, continuously entering and colliding in the hollow inner core, and multiple reflections, counterflows, and dispersions occur between different air flows, greatly attenuating the original sound energy of the air flow and changing the audio frequency, and finally achieving the purpose of noise reduction, and being able to reduce the noise in each frequency band generated when the vacuum pump works.

[0021] 2. For the noise reduction device of the dry vacuum pump provided by the present invention, the outer edge of the support partition is fitted with the inner wall of the noise reduction cavity, and auxiliary air holes are penetrated through the support partition. The support partition fits with the inner wall of the noise reduction cavity to maintain the posture of the hollow inner core inside the noise reduction housing. When the air flow passes through the support partition, it passes through the auxiliary air holes and the air passing gaps, and is divided into multiple strands, increasing the probability of expansion between the air flows and improving the noise reduction effect.

[0022] 3. For the noise reduction device of the dry vacuum pump provided by the present invention, an elastic member is installed between the hollow inner core and the air outlet end of the noise reduction cavity, and the elastic member is in a compressed state to apply a biasing force in the direction away from the air outlet end to the hollow inner core. By setting the elastic member, the hollow inner core is pressed tightly in the noise reduction cavity. When the kinetic energy of the air flow entering the noise reduction cavity is too large, causing the hollow inner core to move, the elastic member can slow down the movement amplitude of the hollow inner core, preventing the hollow inner core from colliding with the inner wall of the noise reduction cavity and generating additional noise, and improving the stability of the noise reduction device during operation.

[0023] 4. For the noise reduction device of the dry vacuum pump provided by the present invention, the air inlet end of the noise reduction cavity is provided with a tapered section, and the check member is installed in the tapered section. By setting the air inlet end of the noise reduction cavity as a tapered section, after the check member is not impacted by the air flow, it can automatically slide into the tapered section under its own gravity, blocking and sealing the air inlet of the noise reduction cavity, effectively preventing the gas from flowing back to the vacuum pump, and realizing the protection of the vacuum pump equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1This is a schematic structural diagram of the noise elimination device for a dry vacuum pump provided in the embodiment of the present invention.

[0026] Figure 2 This is an exploded view of the noise elimination device for a dry vacuum pump provided in the embodiment of the present invention.

[0027] Figure 3 This is a schematic internal structure diagram of the noise elimination device for a dry vacuum pump provided in the embodiment of the present invention.

[0028] Figure 4 This is a schematic structural diagram of the shell body provided in the embodiment of the present invention.

[0029] Figure 5 This is a schematic structural diagram of the end cover provided in the embodiment of the present invention.

[0030] Figure 6 This is a schematic structural diagram of the hollow inner core provided in the embodiment of the present invention.

[0031] Explanation of reference numerals: 1. Shell body; 2. Check valve; 3. Hollow inner core; 4. Elastic member; 5. End cover; 6. O-ring; 7. Retaining ring for hole; 8. Support partition; 9. Noise elimination cavity; 10. Air inlet; 11. Air outlet. Detailed implementation manners

[0032] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed 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, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0035] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] Embodiment 1

[0037] As Figures 1 to 6 shown, a noise reduction device for a dry vacuum pump provided in this embodiment is installed at the exhaust end of the dry vacuum pump during use for noise reduction of the vacuum pump. The noise reduction device includes a noise reduction housing and a hollow inner core 3 and a check valve 2 installed inside the noise reduction housing.

[0038] A noise reduction cavity 9 is provided inside the noise reduction housing. The hollow inner core 3 is installed in the noise reduction cavity 9. At least one layer of support partition 8 is connected to the outer wall of the hollow inner core 3. A gas passing gap is reserved between the support partition 8 and the inner wall of the noise reduction cavity 9. Through holes are provided through the side wall of the hollow inner core 3. In order to make the air flow power from different holes different, multiple through holes have various pore diameters, which can increase the reflection and counter-flushing ability of the air flow in the inner cavity of the hollow inner core 3, make the air flow more dispersed, and enhance the noise reduction effect.

[0039] The check valve 2 is installed inside the noise reduction cavity 9 on the side close to the air inlet 10 of the noise reduction housing. The outer wall of the check valve 2 is adapted to fit and abut against the air inlet 10. The check valve 2 has a first state in which it abuts against the air inlet 10 under its own gravity to block the air inlet 10, and a second state in which it separates from the air inlet 10 under the action of air flow to allow gas to enter the noise reduction cavity 9. Specifically, a conical section is provided at the air inlet end of the noise reduction cavity 9, and the air inlet 10 is provided at the end with a smaller opening size of the conical section. The check valve 2 is installed inside the conical section. The check valve 2 is spherical or conical or pyramidal or frustum-shaped or prismatic. In this embodiment, the air inlet end of the noise reduction cavity 9 is a conical section, and the check valve 2 is spherical. When the noise reduction device of the dry vacuum pump is working, the air inlet 10 of the noise reduction cavity 9 is arranged downward, so that the check valve 2 fits against the inner wall of the conical section under its own gravity to block the air inlet 10.

[0040] The outer edge of the support partition plate 8 is fitted with the inner wall of the sound-absorbing cavity 9. Auxiliary air holes are penetrated through the support partition plate 8. A compression spring serving as the elastic member 4 is installed between the hollow inner core 3 and the air outlet end of the sound-absorbing cavity 9. The elastic member 4 is in a compressed state to apply a biasing force to the hollow inner core 3 in a direction away from the air outlet end. The sound-absorbing housing includes a housing body 1 and an end cover 5. The end cover 5 is detachably installed at the air outlet end of the housing body 1. An air outlet 11 is provided on the end cover 5. A sealing assembly is installed between the housing body 1 and the end cover 5. An installation groove is provided on the side wall of the end cover 5, and at least part of the sealing assembly is installed in the installation groove. Specifically, the sealing assembly includes an O-ring 6 and a hole retaining ring 7. The end cover 5 is welded by a vacuum joint and a circular plate. The end cover 5 is installed inside the housing body 1. The outer side wall of the end cover 5 is slidably matched with the inner side wall of the housing body 1. An installation groove is provided on the outer side wall of the end cover 5 for installing the O-ring 6, and a convex platform is machined on the inner side for limiting the compression spring. A clamping groove is provided on the inner side wall at the air outlet end of the housing body 1, and the hole retaining ring 7 is installed in the clamping groove. One end of the compression spring presses the hollow inner core 3 inside the sound-absorbing housing, and the other end presses the end cover 5 on the hole retaining ring 7.

[0041] A conical air inlet 10 is provided at the lower end of the sound-absorbing housing, and a groove for the hole retaining ring 7 is provided at the upper end. The hollow inner core 3 is a hollow tube with small holes. Three support partition plates 8 are welded and fixed on its outer side wall. The three support partition plates 8 are arranged in parallel and along the axial direction of the hollow inner core 3. The upper and lower ends of the hollow inner core 3 are closed. The outer diameters of the upper and lower support partition plates 8 are the same as the inner diameter of the sound-absorbing housing, and auxiliary air holes are provided on the support partition plates 8. The outer diameter of the middle support partition plate 8 is smaller than the inner diameter of the sound-absorbing housing, and no holes are provided on the middle support partition plate 8. A convex platform is left at the upper end of the hollow inner core 3 for limiting the compression spring. When the dry vacuum pump unit works, the gas flushes open the sealing ball serving as the check member 2, and the air flow is first dispersed into the sound-absorbing cavity 9 of the conical section. The air flow weakened by reflection and counter-flushing in the chamber of the first conical section enters the second sound-absorbing cavity 9 through the auxiliary air holes on the lower support partition plate 8 of the hollow inner core 3. The air flow is reflected, counter-flushed and dispersed in the second sound-absorbing cavity 9. Part of it enters the third sound-absorbing cavity 9 through the air passing gap between the middle support partition plate 8 and the inner wall of the sound-absorbing cavity 9, and the other part enters the inside of the hollow inner core 3 through the air passing holes and then enters the third sound-absorbing cavity 9 through the upper air passing holes. The air flows in different directions converge in the third sound-absorbing cavity 9 and are reflected and counter-flushed again. Finally, the air flow weakened multiple times enters the fourth sound-absorbing cavity 9 through the auxiliary air holes of the upper support partition plate 8, is further weakened and then discharged. Through multiple processes such as dispersion, weakening, and small hole diffusion, the original sound energy of the air flow is greatly attenuated and the sound frequency is changed, and finally the purpose of noise reduction is achieved. When the dry pump unit stops running, the sealing ball falls by its own weight and forms a seal with the conical surface, effectively preventing gas from flowing back and realizing equipment protection.

[0042] The muffler device provided in this embodiment has a check valve function: the sealing ball serving as the check member 2 is vertically arranged and cooperates with the conical air inlet 10, so that the air flow can push open the sealing ball and enter the muffler cavity 9 during operation, and when the operation stops, the sealing ball drops by its own weight to block the air inlet 10 to prevent gas backflow. It has excellent noise reduction function: when the air flow enters the interior of the muffler housing and flows through multiple groups of variable-diameter holes and the diffusion chambers of the hollow inner core 3, the air flow circulation length and sound energy consumption can be greatly increased, achieving excellent noise reduction function. The air inlet and outlet 11 adopts a standard vacuum connector and is connected to the equipment by a clamp, which is simple and convenient to install. There are few internal components, and the integral hollow inner core 3 is adopted. The hollow inner core 3 is divided into three layers, dividing the inner cavity of the muffler device into four muffler cavities 9. The hollow inner core 3 is provided with through holes of different diameters. By increasing the air flow circulation length and multiple air flow diffusions, the sound energy can be consumed to the greatest extent and the air flow audio frequency can be changed, realizing a more effective noise reduction function in a smaller device volume. The hollow inner core 3 is tightly pressed by a compression spring in both directions, and the outside is limited by a shaft retaining ring, eliminating redundant fixing methods and fixing components, reducing the product volume while ensuring the reliability of the components, improving the assembly efficiency and reducing the assembly difficulty. During assembly, the air inlet 10 of the muffler housing is placed downward on the workbench, the sealing ball and the hollow inner core 3 are placed in, the compression spring is installed above the hollow inner core 3, the O-ring 6 is installed in the installation groove of the end cover 5, the O-ring 6 and the end cover 5 assembly are pressed into the shell body 1 to compress the compression spring to make way for the retaining ring groove, and finally the hole retaining ring 7 is installed into the groove of the muffler housing, the end cover 5 is released, and the end cover 5 returns to its position and tightly presses the hole retaining ring 7 under the action of the compression spring. The assembly can be completed without redundant processes and special assembly tools, greatly reducing the overall product volume, improving the production efficiency, and being able to reduce the production cost.

[0043] As an alternative implementation, an internal thread is provided on the end cover 5, and an external thread is provided on the shell body 1. The end cover 5 is threadedly connected to the shell body 1. An installation groove is provided on the inner side wall of the end cover 5, the sealing member is an O-ring, and the O-ring is completely installed in the installation groove to seal the end cover 5 and the shell body 1.

[0044] Embodiment 2

[0045] This embodiment provides a dry vacuum pump unit, which has the dry vacuum pump muffler device described in Embodiment 1. The dry vacuum pump muffler device is installed at the exhaust end of the dry vacuum pump body. When the dry vacuum pump unit is working, the dry vacuum pump body enters the muffler device and then discharges, which can greatly reduce the frequency of the air flow and reduce the noise generated by the dry vacuum pump during operation.

[0046] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A dry vacuum pump silencing device, characterized in that, Comprising: A silencing housing, inside which a silencing cavity (9) is provided. The silencing housing includes a housing body (1) and an end cover (5). The end cover (5) is detachably installed at the air outlet end of the housing body (1), and an air outlet (11) is provided on the end cover (5); A hollow inner core (3), installed in the silencing cavity (9). At least one layer of support partition (8) is connected to the outer wall of the hollow inner core (3). A gas passage gap is reserved between the support partition (8) and the inner wall of the silencing cavity (9). Through holes are formed through the side wall of the hollow inner core (3). The outer edge of the support partition (8) is fitted with the inner wall of the silencing cavity (9). Auxiliary air holes are formed through the support partition (8). An elastic member (4) is installed between the hollow inner core (3) and the air outlet end of the silencing cavity (9). The elastic member (4) is in a compressed state to apply a biasing force to the hollow inner core (3) in a direction away from the air outlet end; A check member (2), installed on one side of the silencing cavity (9) close to the air inlet (10) of the silencing housing. A tapered section is provided at the air inlet end of the silencing cavity (9). The check member (2) is installed in the tapered section. The outer wall of the check member (2) is adapted to be in close contact with the air inlet (10). The check member (2) has a first state in which it abuts against the air inlet (10) under its own gravity to block the air inlet (10), and a second state in which it separates from the air inlet (10) under the action of air flow to allow gas to enter the silencing cavity (9).

2. The dry vacuum pump silencing device according to claim 1, characterized in that, The check member (2) is spherical or conical or frustum-shaped.

3. The dry vacuum pump silencing device according to claim 1, characterized in that, A sealing assembly is installed between the housing body (1) and the end cover (5).

4. The dry vacuum pump silencing device according to claim 3, characterized in that, An installation groove is provided on the side wall of the end cover (5), and at least part of the sealing assembly is installed in the installation groove.

5. The dry vacuum pump silencing device according to claim 1, characterized in that, The plurality of through holes have various pore diameters.

6. A dry vacuum pump unit, characterized in that, A dry vacuum pump silencing device according to any one of claims 1 to 5.

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