Vacuum pump suitable for vacuum environment

Abstract

The utility model provides a vacuum pump suitable for a vacuum environment, and belongs to the technical field of machinery. The problem of how to reduce the working noise of the vacuum pump is solved. The vacuum pump suitable for the vacuum environment comprises a pump body and a cooler, the vacuum pump suitable for the vacuum environment further comprises a silencer and a cooling box internally provided with a cavity, the cooler is connected to the interior of the cavity of the cooling box, the pump body is connected to the cooling box and communicated with the cavity of the cooling box, and the silencer is arranged in the cooling box. The cooling box is provided with an air return pipe connected with the pump body and the cooler, a silencing channel is arranged in a cavity of the cooling box in a continuous bending mode, one end of the silencing channel is communicated with the cooler, and the air inlet end of the silencer is connected with the cooling box and communicated with the other end of the silencing channel. The vacuum pump suitable for the vacuum environment can reduce working noise.

Description

TECHNICAL FIELD

[0001] The utility model belongs to mechanical technical field relates to a kind of vacuum pump suitable for vacuum environment. BACKGROUND

[0002] Vacuum pump is the device or equipment that is obtained by using mechanical, physical, chemical or physical-chemical method to pump the container to be pumped, and the common vacuum pump in prior art includes dry screw vacuum pump, water ring pump, reciprocating pump, slide valve pump, rotary vane pump, Roots pump and diffusion pump etc..Among them, Roots pump, also known as Roots vacuum pump, is a variable-volume vacuum pump with two counter-rotating lobed rotors inside the pump, and the rotors and the inner wall of the pump casing have small gaps without contact.

[0003] The conventional Roots vacuum pump structure in prior art is as follows: the Roots pump disclosed in Chinese patent (grant announcement number: CN209370073U) includes a pump shell, a cavity is arranged in the pump shell, the pump shell has an inlet and an outlet, the inlet and the outlet are both communicated with the cavity, a driving rotor and a driven rotor are arranged in the cavity and are in meshing relationship, the driving rotor includes four driving blades, the driven rotor includes four driven blades, the driving blades are twisted towards one side from front end to rear end and form a twist angle one, the driven blades are twisted towards the other side from front end to rear end and form a twist angle two, the twist angle one is the same as the twist angle two, and the driving blades and the driven blades are both provided with sealing parts capable of abutting against the cavity wall of the cavity. However, in actual use, the gas temperature near the outlet of the cavity is high, and the gas temperature near the inlet of the cavity is low, so that the gas pressure at different positions in the cavity is inconsistent, which affects the air tightness in the cavity of the pump, and also causes noise during operation.

[0004] For this situation, the prior art uses corresponding technical means, such as the air-cooled high-pressure-difference Roots pump disclosed in Chinese patent (grant announcement number: CN214007505U), which includes a pump shell, the top of the pump shell has an air inlet, the bottom of the pump shell has an air outlet, and the two sides of the pump shell are also provided with return cooling air inlets. The Roots pump further includes a cooler and a return air pipe, the air outlet of the pump shell is communicated with the inlet of the cooler, and the outlet of the cooler is communicated with the return cooling air inlet through the return air pipe. That is, the cooler is used to cool the gas discharged through the air outlet, and the gas is re-input into the pump body through the return cooling air inlets on both sides of the pump body to cool the rotors, balance the air pressure inside the pump body, reduce the pressure difference in the pump shell, and ensure pressure balance while reducing working noise.

[0005] However, according to the drawings of the specification of CN214007505U Figure 1It can be seen that the exhaust pipe structure of the cooling device is actually a three-outlet structure, and most of the cold gas is directly discharged to the outside through the exhaust pipe, although the rotation of the rotor can make part of the gas reflow through the return pipe, but the actual amount is only a very small part compared to the gas discharged to the outside, so the effect of cooling the pump shell is limited, and the gas discharged to the outside through the exhaust pipe will maintain a high flow rate due to the subsequent gas pressure, and the rapidly flowing gas will produce a loud noise at the exhaust port of the exhaust pipe, resulting in noise phenomenon still exists. SUMMARY

[0006] The utility model aims at the above -mentioned problem existing in prior art, proposes a vacuum pump suitable for vacuum environment, the technical problem that the utility model wants to solve is: how to reduce the working noise of vacuum pump.

[0007] The utility model discloses a vacuum pump suitable for vacuum environment, including pump body and cooler, its characterized in that, this vacuum pump suitable for vacuum environment still includes silencer and the cooling box that has the cavity in the inside, the cooler is connected in the cavity of cooling box, the pump body is connected on cooling box and is communicated the cavity of cooling box, be equipped with the return pipe of connecting pump body and the cooler on cooling box, the cavity of cooling box has the continuous bending arrangement and one end is communicated silencer passage of the cooler, the other end of silencer inlet and cooling box is connected and is communicated silencer passage.

[0008] It needs to be realized that the vacuum pump suitable for vacuum environment is in a vacuum working environment, and the heat generated inside cannot be effectively discharged. To solve this problem, the vacuum pump suitable for vacuum environment of the application is provided. The high-temperature gas is input into the cavity of the cooling box from the pump body. The gas entering the cavity is divided into two parts. One part of the gas is input into the cooler through the cavity. The cooler can adopt the existing technology, and the part of the gas is cooled by the cooler and then returns to the pump body through the return pipe to cool the pump body. On this basis, the other part of the gas is directly discharged outward through the cooling box to ensure the normal operation of the vacuum pump. In this process, the gas directly discharged outward has a faster flow rate, so noise will be generated when the gas is discharged outside and at the gas outlet of the cooling box. To solve this problem, the application first sets a sound-attenuating channel in the cooling box. The part of the gas directly discharged outward flows outward through the sound-attenuating channel. Because the sound-attenuating channel is continuously curved, the flow rate of the part of the gas is slowed down under the continuous impact. Then the gas with reduced speed enters the sound-attenuating device through the sound-attenuating channel and is discharged outward. The sound-attenuating device can adopt the existing technology to prevent noise from being generated when the gas is discharged. In addition, the use of the sound-attenuating channel and the sound-attenuating device can slow down the flow rate of the gas discharged outward through the sound-attenuating device as much as possible, so that more gas can enter the cooler through the cavity of the cooling box for cooling and then be input into the pump body through the return pipe from the cooler. Thus, the amount of cold gas provided for the pump body is more sufficient, and the cooling effect of the pump body is ensured to reduce the pressure difference in the pump and reduce the working noise.

[0009] In the vacuum pump suitable for vacuum environment, the cooling box is in a cylindrical shape, the pump body is connected to the middle part of the outer wall of the cooling box, the cooler is connected to one end of the inside of the cooling box, and a plurality of sound-attenuating baffles are arranged in an axially staggered and spaced manner on the inside wall of the other end of the cooling box. The sound-attenuating channel is formed between the sound-attenuating baffles. Specifically, the sound-attenuating channel is formed by the sound-attenuating baffles arranged in a staggered manner and the inner wall of the cavity of the cooling box. The sound-attenuating channel and the cooler are respectively arranged at the two ends of the cooling box. The pump body takes in gas in the middle of the cooling box and discharges gas at the two ends of the cooling box, thereby achieving the flow splitting of the gas.

[0010] In the vacuum pump suitable for vacuum environment, the vacuum pump suitable for vacuum environment further comprises a check valve, and the gas outlet end of the sound-attenuating device is connected to the valve inlet of the check valve. The existence of the check valve stabilizes the pressure of the part of the gas discharged from the sound-attenuating channel and the sound-attenuating device. In the entire gas discharge process, the gas pressure output through the sound-attenuating device needs to be raised to the opening threshold of the check valve before it can be opened and discharged. This helps to increase the amount of gas input into the cooler. The arrangement of the check valve can also prevent the reverse flow of external air through the sound-attenuating device and the cooling box.

[0011] In the vacuum pump suitable for vacuum environment, the check valve comprises a valve body and a piston valve weight, the piston valve weight is slidingly connected in the valve body and blocks the valve inlet of the valve body. Specifically, the check valve is blocked by the piston valve weight slidingly connected in the valve body, and in the specific working process, when the gas pressure in the muffler reaches a certain value (i.e. the opening threshold of the check valve), the piston valve weight pushed by the gas moves to expose the valve inlet, at this time the gas in the muffler enters the valve body and is discharged outward through the valve outlet, and in this process the gas pressure in the muffler continuously decreases, at this time the piston valve weight can slide to reset to block the valve inlet, thereby achieving the purpose of automatic control of exhaust, and it is worth mentioning that through this setting, the gas pressure in the cooling box cavity also increases, and when the check valve has not been opened, the gas entering the cooling box cavity from the valve body can only enter the cooler for cooling and re-enter the valve body through the cooler pipe, thereby ensuring that the pump body can provide more sufficient cooling gas to reduce the noise generated by the pump body during operation.

[0012] In the vacuum pump suitable for vacuum environment, the check valve further comprises a valve cover fixed on the valve body, the valve cover has a damping pipe extending into the valve body, the piston valve weight comprises a sealing head, a cover plate and a piston rod axially connected and fixed between the sealing head and the cover plate along the damping pipe, the cover plate covers the valve inlet of the valve body, and the sealing head is slidingly connected in the damping pipe and forms a damping cavity in the damping pipe between the sealing head and the valve cover. Specifically, the control of the piston valve weight is realized by the cooperation of the sealing head and the damping pipe, when the cover plate is pushed upward, the air in the damping cavity is compressed by the extrusion of the sealing head, at this time the air pressure in the damping cavity increases and exerts a force on the sealing head to move and reset, when the gas pressure in the muffler is reduced to less than the gas pressure in the damping cavity, the sealing head can move and reset to block the valve inlet, otherwise the valve inlet is opened.

[0013] In the vacuum pump suitable for vacuum environment, a rubber pad is circumferentially fixed on the surface of the cover plate, and the rubber pad abuts against the inner wall of the valve body around the valve inlet. In this way, the sealing property of the valve inlet is ensured.

[0014] In the vacuum pump suitable for vacuum environment, the water-cooled negative pressure motor is drivingly connected with the pump body. The water-cooled negative pressure motor is adopted instead of the air-cooled motor to avoid the situation that the gas cannot be cooled due to low density in the vacuum environment.

[0015] Compared with the prior art, the vacuum pump suitable for vacuum environment has the following advantages:

[0016] 1. The gas discharged from the pump body is diverted through the cavity in the cooling box, so that part of the gas is cooled by the cooler and then flows back into the pump body through the return pipe to cool the pump body. At the same time, through the setting of the silencer channel and the silencer, the noise generated by the direct exhaust part of the air is reduced while the flow rate of this part of the gas is blocked, ensuring that more gas can be cooled and returned through the cooler, ensuring that the noise during the operation of the positive air pump is lower.

[0017] 2. By setting the check valve, the flow rate of the direct exhaust gas is further reduced, so that the pressure in the cooling box cavity is self-adjusted and distributed, and the external air is effectively prevented from flowing back into the cooling box through the muffler due to the pressure difference.

[0018] 3. Use cold negative pressure motor instead of air-cooled motor to avoid the situation where cooling cannot be achieved due to low gas density in vacuum environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a simplified structural diagram of a vacuum pump suitable for a vacuum environment.

[0020] Figure 2 It is a cross-sectional view of a check valve.

[0021] Figure 3 This is a schematic diagram of cold gas return of a vacuum pump suitable for a vacuum environment.

[0022] In the figure, 1. Pump body; 2. Cooler; 3. Muffler; 4. Cooling box; 41. Return air pipe; 42. Muffler channel; 43. Muffler baffle; 5. Check valve; 51. Valve body; 52. Piston valve code; 521. Sealing head; 522. Cover plate; 5221. Rubber pad; 523. Piston rod; 53. Valve cover; 531. Damping tube; 5311. Damping chamber; 6. Water-cooled negative pressure motor. DETAILED DESCRIPTION

[0023] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0024] like Figure 1 and Figure 2As shown, the vacuum pump suitable for vacuum environment includes a pump body 1 with an air inlet one, an air outlet one and a back air outlet one, a water-cooled negative pressure motor 6 in driving connection with the pump body 1, a cooling box 4 with a cavity inside and air inlets two, air outlets two and back air outlets two respectively formed on the outer wall thereof, a cooler 2 with an air inlet three and an air outlet three, and a back air pipe 41, wherein the cooling box 4 is in a long tube shape, the air inlet two is formed in the middle of the outer wall of the cooling box 4, the air outlet two and the back air outlet are respectively arranged close to the two ends thereof, the pump body 1 is connected and fixed on the cooling box 4 and makes the air outlet one and the air inlet one communicated, the air inlet three of the cooler 2 and the cavity of the cooling box 4 are communicated, one end of the back air pipe 41 is connected through the back air outlet two and the air outlet two of the cooler 2, and the other end is connected with the back air outlet one. When in operation, the pump body 1 inputs the gas into the cavity of the cooling box 4, and under the action of subsequent air pressure, the gas is continuously cooled and cooled by the cooler 2 to become cold gas, and then flows back to the pump body 1 through the back air pipe 41 to cool the rotor of the pump body 1.

[0025] A plurality of sound-absorbing baffles 43 are fixed in the cavity of the cooling box 4 and are spaced apart along the axial direction of the cooling box 4 between the air inlet two and the air outlet two, and the sound-absorbing baffles 43 and the inner wall of the cavity form a sound-absorbing channel 42 which is continuously curved, one end of the sound-absorbing channel 42 is communicated with the air inlet two through the cavity, the other end is communicated with the air outlet two, and as a further preferred solution, a plurality of air-permeable holes are formed on each sound-absorbing baffle 43 and extend through the two side surfaces thereof.

[0026] In combination Figure 2 , the vacuum pump suitable for vacuum environment includes a muffler 3 and a check valve 5, the muffler 3 is fixed on the cooling box 4 and the air inlet end is communicated with the air outlet two, and the check valve 5 is fixed on the muffler 3 and the valve inlet is communicated with the air outlet end of the muffler 3. It is worth mentioning that the cooler 2 and the muffler 3 can be used in the prior art, and the structure thereof will not be described in detail herein, the check valve 5 includes a valve body 51, a valve cover 53 fixed on the valve body 51 through screws, and a piston valve rod 52 slidably connected in the valve body 51, wherein the valve cover 53 is integrally formed with a damping pipe 531 extending into the interior of the valve body 51 and the port of which is opposite to the valve inlet, the piston valve rod 52 includes a disc-shaped cover plate 522 which blocks the valve, a sealing head 521 slidably connected in the damping pipe 531, and a piston rod 523 formed between the sealing head 521 and the cover plate 522, wherein the sealing head 521 is slidably connected in the damping pipe 531 and forms a damping cavity 5311 together with the inner wall of the valve cover 53 and the inner peripheral wall of the damping pipe 531, and a rubber pad 5221 in the form of a ring is fixed on the cover plate 522 and abuts against the inner wall of the valve body 51.

[0027] In combination with the foregoing scheme, when the vacuum pump suitable for a vacuum environment is in operation, the gas in the cooling box 4 is divided into two parts, one part of which is cooled and returned, as described above, and the other part of which is discharged outwardly via the muffler 3 and the check valve 5. Specifically, the part of the gas is first introduced into the muffling channel 42 in the cavity of the cooling box 4 to stabilize the pressure, so that the flow rate of the gas is preliminarily slowed down, and then is output through the second gas outlet into the muffler 3 to be further damped and reduced in noise, and then the pressure is continuously accumulated to open the cover plate 522, and then is discharged outwardly through the valve outlet after entering the valve body 51 of the check valve 5 via the valve inlet.

[0028] In the above process, the muffling channel 42, the muffler 3, and the check valve 5 can more or less control the flow of the gas discharged to the outside, so as to ensure that the flow rate of the gas is more gentle, avoid the generation of noise, and also increase the air pressure in the cavity applied to the cooler 2, so as to ensure that more sufficient gas can pass through the cooler 2 to be cooled and then flow back to the pump body 1 through the return gas pipe 41 to cool the pump body 1.

[0029] The specific embodiments described herein are merely illustrative of the spirit of the present application. Those skilled in the art to which the present application belongs can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, without deviating from the spirit of the present application or exceeding the scope defined by the appended claims.

[0030] Although the terms such as the pump body 1, the cooler 2, the muffler 3, the cooling box 4, the return gas pipe 41, the muffling channel 42, the muffling partition 43, the check valve 5, the valve body 51, the piston valve code 52, the sealing head 521, the cover plate 522, the rubber pad 5221, the piston rod 523, the valve cover 53, the damping pipe 531, the damping cavity 5311, and the water-cooled negative pressure motor 6 are used more frequently herein, the possibility of using other terms is not excluded. The use of these terms is only for the convenience of describing and explaining the essence of the present application; any kind of additional limitation by interpreting them is contrary to the spirit of the present application.

Claims

1. A vacuum pump suitable for use in a vacuum environment comprising a pump body (1) and a cooler (2), characterised in that, The vacuum pump suitable for vacuum environment further comprises a muffler (3) and a cooling box (4) with a cavity, the cooler (2) is connected in the cavity of the cooling box (4), the pump body (1) is connected to the cooling box (4) and communicates with the cavity of the cooling box (4), the cooling box (4) is provided with a return gas pipe (41) connecting the pump body (1) and the cooler (2), the cavity of the cooling box (4) has a continuously curved muffling channel (42) which communicates with one end of the cooler (2), and the other end of the muffling channel (42) is connected with the cooling box (4) and the muffler (3).

2. The vacuum pump suitable for a vacuum environment according to claim 1, characterized in that: The cooling box (4) is cylindrical, the pump body (1) is connected to the middle of the outer wall of the cooling box (4), the cooler (2) is connected to one end of the inside of the cooling box (4), and a plurality of sound insulation baffles (43) are arranged axially and spaced on the inner wall of the other end of the cooling box (4), and the muffling channel (42) is formed between the sound insulation baffles (43).

3. Vacuum pump suitable for use in a vacuum environment according to claim 1 or 2, characterized in that, The vacuum pump suitable for vacuum environment further comprises a check valve (5), and the valve inlet of the check valve (5) is connected with the gas outlet end of the muffler (3).

4. The vacuum pump suitable for use in a vacuum environment according to claim 3, characterized in that, The check valve (5) comprises a valve body (51) and a piston valve code (52), the piston valve code (52) is slidably connected in the valve body (51) and blocks the valve inlet of the valve body (51).

5. Vacuum pump suitable for use in a vacuum environment according to claim 4, characterized in that, The check valve (5) further comprises a valve cover (53) fixed on the valve body (51), the valve cover (53) has a damping pipe (531) extending into the valve body (51), the piston valve code (52) comprises a sealing head (521), a cover plate (522) and a piston rod (523) axially connected between the sealing head (521) and the cover plate (522) along the damping pipe (531), the cover plate (522) covers the valve inlet of the valve body (51), the sealing head (521) is slidably connected in the damping pipe (531) and forms a damping cavity (5311) in the damping pipe (531) between the sealing head (521) and the valve cover (53).

6. Vacuum pump suitable for use in a vacuum environment according to claim 5, characterized in that, The cover plate (522) is circumferentially fixed with a rubber pad (5221) on the plate surface, and the rubber pad (5221) abuts tightly around the inner wall of the valve inlet of the valve body (51).

7. A vacuum pump suitable for use in a vacuum environment according to claim 1 or 2, characterized in that, The vacuum pump suitable for vacuum environment further comprises a water-cooled negative pressure motor (6), and the water-cooled negative pressure motor (6) is drivingly connected with the pump body (1).

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