A gas filtration device for a vacuum pump in front

Abstract

The present invention relates to the technical field of air compressors, and specifically discloses a gas filtering device in front of a vacuum pump, which includes a housing and an air outlet hole opened on the side wall of the housing. Installation disks and motors are respectively fixedly installed on the two side walls of the housing. An installation frame is arranged inside the housing. A part of the main shaft of the motor that penetrates into the housing and the installation frame is fixedly connected with a rotating shaft. Multiple rows of fins are distributed on the side wall of the rotating shaft. The fins are alternately composed of fixed fins and rotating fins with opposite directions. By driving the filter cotton to switch back and forth between two states, the density of the filter cotton increases when it is in the compressed state, improving the filtering accuracy of the filter cotton. When the filter cotton switches to the extended state, the density decreases, reducing the filtering accuracy of the filter cotton, reducing the air resistance suffered by the gas passing through the filter cotton, which is more conducive to subsequent vacuum extraction or vacuum maintenance. At the same time, the ultimate vacuum degree of the container after extraction is also improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air compressors, and specifically to a gas filtration device in front of a vacuum pump. Background Art

[0002] A vacuum pump is a device used to evacuate gases from a closed container to create and maintain a vacuum. They are widely used in scientific research, industry, healthcare, and aviation. When a vacuum pump is operating, solid particles, dust, liquid droplets, and other impurities may enter the vacuum pump, causing wear or damage to the inside of the pump body. Therefore, it is necessary to filter the gas during the process of creating or maintaining a vacuum.

[0003] For example, Chinese Patent No. CN114718875B discloses a gas filtration device in front of a vacuum pump with a function of preventing corrosion of components. In this invention, when the compression impellers on the driving shaft and the driven shaft rotate, gas is drawn through the intake pipe. The gas passes through the fixed ring through the intake pipe and enters the inside of the upper housing and the lower housing. When the rotating ring rotates, the filter member is driven to rotate by the fixed ring. The gas in the fixed ring will pass through the through holes and be filtered by the filter cotton. In this invention, the filter cotton rotates to share the impurities in the gas. While filtering the gas, the rotation of the filter cotton will increase the filtering effect and prevent the filter cotton from getting blocked, reducing the replacement frequency of the filter cotton.

[0004] However, when evacuating a container, due to the different masses of the gases in the container, lighter gases (such as hydrogen) will be drawn out first, simultaneously driving denser particles or dust through the filter cotton at a higher speed (lighter gases have better fluidity, and denser particles are more likely to overcome air resistance and be sucked out). Therefore, filter cotton with a higher filtering precision is required to filter impurities to prevent particles from passing through the filter cotton. As the gas in the container decreases, the pumping efficiency of the vacuum pump will decline, and the remaining gas in the container is heavier, and the density of the remaining particles is also smaller. At this time, it is necessary to reduce the density of the filter cotton to reduce the air resistance and increase the attraction of the vacuum pump to the gas, so as to improve the ultimate vacuum degree of the vacuum pump. However, the existing filtering devices and filter cotton cannot meet the requirements of different stages. Summary of the Invention

[0005] The purpose of the present invention is to provide a gas filtration device in front of a vacuum pump to solve at least one of the technical problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following technical solution: A gas filtration device in front of a vacuum pump, comprising a housing and an air outlet hole opened on the side wall of the housing. Installation discs and motors are fixedly installed on the two side walls of the housing respectively. An installation frame is arranged inside the housing. A rotating shaft is fixedly connected to the part of the main shaft of the motor that penetrates into the housing and the installation frame. Multiple rows of fins are distributed on the side wall of the rotating shaft. The fins are alternately composed of fixed fins and rotating fins with opposite directions. An air inlet pipe capable of communicating with the installation frame is installed on the side wall of the installation disc. A filtering part for filtering gas is arranged in the pipeline between the air inlet pipe and the installation frame. The filtering part includes filter cotton. The filter cotton has two states. State one: the filter cotton is in a compressed state, improving the filtering accuracy and increasing the air resistance. State two: the filter cotton is in an extended state, reducing the filtering accuracy and decreasing the air resistance.

[0007] Preferably, the filtering part includes two fixing rings that can be installed in the pipeline between the air inlet pipe and the installation frame. A corrugated pipe is connected between the two fixing rings. The filter cotton is fixedly installed between the two fixing rings.

[0008] Preferably, two limiting discs are rotatably installed on the inner wall of the housing. Card slots for inserting the fixing rings are opened on the opposite surfaces of the two limiting discs. After the fixing rings are inserted into the card slots, they are in an inscribed state with the limiting discs. A plurality of elastic telescopic rods are also fixedly connected between the two limiting discs. A cylinder fixedly installed on the inner wall of the housing is arranged on the side of one of the limiting discs. The end of the driving shaft of the cylinder abuts against the side wall of the limiting disc and can slide on the side wall of the limiting disc. A sliding ring capable of sliding inside the housing is fixedly connected to one side of the limiting disc.

[0009] Preferably, a reduction motor is fixedly installed on the side wall of the installation disc. A driving gear is fixedly connected to the part of the main shaft of the reduction motor that penetrates into the installation disc. A transmission gear meshing with the driving gear is fixedly installed on the outer wall of the limiting disc. A side channel for the filtering part to slide out is opened on the side wall of the housing, and a door plate is arranged in the side channel.

[0010] A firing part is also arranged inside the housing. When the card slot rotates to communicate with the side channel, the firing part ejects the filtering part from the card slot.

[0011] Preferably, the firing part includes a special-shaped cavity formed in the shell and located on the side of the limit disk. An installation hole is formed in the limit disk, and a firing pin is slidably installed in the installation hole. A compression spring for applying a force to move the firing pin closer to the limit disk is installed between the firing pin and the installation hole. One end of the firing pin extending into the special-shaped cavity is fixedly connected with an elastic pin. A sliding groove for the elastic pin to insert and slide is formed on the inner wall of the special-shaped cavity. The sliding groove is composed of two arc-shaped sliding ways that are farther and farther away from the center of the limit disk in the sliding direction of the elastic pin and a sliding way that coincides with the radius line of the limit disk connected end to end. Each section of the sliding way gradually becomes shallower in the sliding direction of the elastic pin. A sliding groove for the elastic pin to slide along the telescopic direction of the air cylinder is also formed on the inner wall of the shell.

[0012] Preferably, a bottom box is fixedly connected to the bottom of the shell. A top plate is slidably installed in the bottom box. A spring is arranged between the top plate and the inner bottom wall of the bottom box. The sliding ring is tangent to the limit disk.

[0013] Preferably, a laser emitter and a laser receiver that coincide with the diameter line of the sliding ring are fixedly installed in the groove on the inner wall of the installation frame. The laser receiver is electrically connected to the air cylinder. An elastic net is also fixedly installed on the inner wall of the installation frame. An optical blocking strip is fixedly installed at the center of the elastic net.

[0014] Preferably, an elastic buckle is arranged on the side wall of the clamping groove.

[0015] Preferably, the length of the sliding groove is greater than the sliding distance of the elastic pin.

[0016] Preferably, plastic meshes for limiting the filter cotton are fixedly installed in both of the two fixing rings.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. The present invention drives the filter cotton to switch back and forth between two states. When the lighter gas in the container drives the denser particles or dust in the container to pass through the filter cotton at a relatively fast flow rate, the filter cotton is in State 1, the compressed state, so that the internal gaps become smaller and the density increases, improving the filtering accuracy of the filter cotton. As the gas in the container decreases to a certain extent and the pumping efficiency of the air pump drops, the filter cotton is switched to State 2, the stretched state, so that the internal gaps of the filter cotton increase and the density decreases, reducing the filtering accuracy of the filter cotton, reducing the wind resistance suffered by the gas passing through the filter cotton, reducing the extraction resistance of the device to the gas, being more conducive to subsequent vacuum pumping or vacuum maintenance, and at the same time improving the ultimate vacuum degree of the device. When the filter cotton is switched to State 2, the stretched state, while reducing the wind resistance, it increases the attraction of the device to the particles or dust in the container, enabling these tiny particles or dust to be discharged from the container. Moreover, the filter cotton with a lower density, due to its internal natural dust storage cavity, is more conducive to achieving high-precision filtering of such dust, so that the device maintains high-precision filtering of the inhaled gas and improves the filtering effect of the device.

[0019] 2. The present invention can quickly eject the discarded filter part from the shell through the sliding fit of the elastic pin in the chute and the rotation of the limit disk, enabling the filter cotton to be quickly disassembled and replaced after excessive particles or dust accumulate on it, avoiding the blockage of the air flow caused by the long-term use of the filter cotton and preventing the device from idling and jamming.

[0020] 3. After the striker knocks the fixed ring in the limit disk to eject the filter part from the shell, the reduction motor drives the driving gear to drive the transmission gear and the limit disk to reset. At this time, the spring in the bottom box pushes the top plate to drive the filter part in the bottom box to move up into the limit disk, completing the automatic replacement of the filter part and realizing the quick replacement of the filter cotton, solving the pain points of filter cotton replacement at the present stage, reducing the number and duration of device shutdowns for maintenance, and reducing the use cost of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a three-dimensional structural schematic diagram of the present invention;

[0022] Figure 2 is a side sectional view of the present invention;

[0023] Figure 3 is a sectional view of the three-dimensional structure of the present invention;

[0024] Figure 4 is a three-dimensional structural schematic diagram of the internal structure of the present invention;

[0025] Figure 5 is a sectional view of the mounting plate in the present invention;

[0026] Figure 6 is a sectional view of the firing part in the present invention;

[0027] Figure 7 It is an exploded view of the three-dimensional structure of the filter part in the present invention;

[0028] Figure 8 For the present invention Figure 3 A in the enlarged view;

[0029] Figure 9 For the present invention Figure 3 The enlarged view of point B in the figure;

[0030] Figure 10 It is a cross-sectional schematic diagram of the filter part after compression in the present invention;

[0031] Figure 11 It is a cross-sectional schematic diagram of the filter portion after extension in the present invention.

[0032] In the figure: 1. shell; 2. mounting plate; 3. motor; 4. rotating shaft; 5. fin; 6. mounting frame; 7. cylinder; 8. sliding ring; 9. limiting plate; 10. slot; 11. transmission gear; 12. elastic telescopic rod; 13. bellows; 14. fixing ring; 15. filter cotton; 16. striker; 17. elastic pin; 18. compression spring; 19. special-shaped cavity; 20. slide groove; 21. door panel; 22. driving gear; 23. top plate; 24. spring; 25. air inlet pipe; 26. elastic net; 27. laser transmitter; 28. laser receiver; 29. light-blocking strip; 30. sliding groove; 31. reduction motor; 32. bottom box. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] See also Figures 1 to 11, the present invention provides a technical solution: a gas filtration device in front of a vacuum pump, including a housing 1 and an air outlet hole opened on the side wall of the housing 1. Installation disks 2 and motors 3 are fixedly installed on the two side walls of the housing 1 respectively. An installation frame 6 is arranged inside the housing 1. A part of the main shaft of the motor 3 passing through the housing 1 and the installation frame 6 is fixedly connected with a rotating shaft 4. Multiple rows of fins 5 are distributed on the side wall of the rotating shaft 4. The fins 5 are alternately composed of fixed fins and rotating fins with opposite directions. An air inlet pipe 25 capable of communicating with the installation frame 6 is installed on the side wall of the installation disk 2. A filtering part for filtering the gas is arranged in the pipeline between the air inlet pipe 25 and the installation frame 6. The filtering part includes a filter cotton 15. The filter cotton 15 has two states. State one, the filter cotton 15 is in a compressed state, improving the filtering accuracy and increasing the air resistance. State two, the filter cotton 15 is in an extended state, reducing the filtering accuracy and reducing the air resistance.

[0035] When this device is in use, first, the air inlet pipe 25 is hermetically connected to the container that needs to extract or maintain a vacuum. Subsequently, the motor 3 is started to drive the rotating shaft 4 to drive the part of the fins 5 fixedly connected to the rotating shaft 4. The fixed fins and rotating fins arranged alternately generate an attraction force inside the housing 1, and the inhaled gas is filtered through the filtering part. Subsequently, the filtered gas is discharged outside the housing 1 through the air outlet hole opened on the outer wall of the housing 1, completing the extraction of the gas inside the container or maintaining the vacuum state inside the container.

[0036] During the process of vacuum pumping, by driving the filter cotton 15 to switch back and forth between the two states, when the lighter gas inside the container drives the denser particles or dust inside the container to pass through the filter cotton 15 at a faster flow rate, the filter cotton 15 is in state one, the compressed state. Specifically, refer to Figure 10 , at this time, the filter cotton 15 is compressed, making the internal gap smaller and the density larger, improving the filtering accuracy of the filter cotton 15. It can prevent particles with a smaller volume but a larger mass from passing through the filter cotton 15 under the action of high-speed air flow, improving the filtering effect of the inhaled gas. As the gas inside the container decreases to a certain extent and the pumping efficiency of the vacuum pump decreases, at this time, the filter cotton 15 is switched to state two, the extended state. Specifically, refer to Figure 11 , since the filter cotton 15 is stretched, the internal gap of the filter cotton 15 increases and the density decreases, reducing the filtering accuracy of the filter cotton 15, reducing the air resistance suffered by the gas passing through the filter cotton 15, reducing the extraction resistance of the device to the gas, being more conducive to subsequent vacuum pumping or vacuum maintenance, and at the same time improving the ultimate vacuum degree of the device.

[0037] It is worth mentioning that after the gas in the container is reduced to a certain extent, the remaining gas in the container is heavier at this time, and it is mostly composed of particles or dust with small density and volume inside. Since these particles or dust cannot easily break through the air resistance, they move irregularly in the container. When the filter cotton 15 switches to the second state, the extended state, while reducing the wind resistance, it increases the attraction of the device to the particles or dust in the container, enabling these tiny particles or dust to be discharged from the container. Moreover, due to the natural dust storage cavity contained in the filter cotton 15 with a lower density, it is more conducive to achieving high-precision filtration of such dust, thereby enabling the device to maintain high-precision filtration of the inhaled gas and improving the filtration effect of the device.

[0038] Furthermore, the filtering part includes two fixing rings 14 that can be installed in the pipeline between the air inlet pipe 25 and the mounting frame 6. A corrugated pipe 13 is connected between the two fixing rings 14, and the filter cotton 15 is fixedly installed between the two fixing rings 14.

[0039] According to the above-mentioned embodiment, a specific embodiment of the filtering part is provided. For details, refer to Figure 7 , since the filter cotton 15 is arranged in the corrugated pipe 13, when the two fixing rings 14 are pushed to approach or move away from each other, the filter cotton 15 inside the corrugated pipe 13 can be compressed or extended, completing the switching of the filter cotton 15 between the two states as described above. Among them, the corrugated pipe 13 is made of an elastic material and can be compressed or extended axially for adjustment.

[0040] Furthermore, two limiting discs 9 are rotatably installed on the inner wall of the housing 1. Slots 10 for inserting the fixing rings 14 are formed on the opposite surfaces of the two limiting discs 9. After the fixing rings 14 are inserted into the slots 10, they are in an inscribed state with the limiting discs 9. A plurality of elastic telescopic rods 12 are also fixedly connected between the two limiting discs 9. A cylinder 7 fixedly installed on the inner wall of the housing 1 is provided on the side of one of the limiting discs 9. The end of the driving shaft of the cylinder 7 abuts against the side wall of the limiting disc 9 and can slide on the side wall of the limiting disc 9. A sliding ring 8 that can slide in the housing 1 is fixedly connected to one side of the limiting disc 9.

[0041] According to the above embodiments, when the cylinder 7 drives the limiting disks 9 to approach each other, the elastic telescopic rod 12 will be driven to compress. When the cylinder 7 retracts the driving shaft, the elastic telescopic rod 12 can drive the two limiting disks 9 to move away from each other, completing the back-and-forth switching of the filter cotton 15 between the two states as described above. The end of the driving shaft of the cylinder 7 abuts against the side wall of the limiting disk 9 and can slide on the side wall of the limiting disk 9, so that the limiting disk 9 can still maintain contact with the limiting disk 9 and not detach even when eccentrically rotating with the cylinder 7. Since the limiting disk 9 is tangent to the fixing ring 14 inserted into the card slot 10, the fixing ring 14 is more easily taken out of the card slot 10, facilitating the replacement of the filter part in the subsequent process. And because a sliding ring 8 that can slide in the housing 1 is fixedly connected to one side of the limiting disk 9, the limiting disk 9 can still maintain the seal of the air flow channel through the sliding ring 8 during the process of approaching each other, so that the filtered gas will not enter the interior of the housing 1, ensuring the sealing effect of the pipeline.

[0042] Further, a reduction motor 31 is fixedly installed on the side wall of the mounting disk 2. A driving gear 22 is fixedly connected to the part of the main shaft of the reduction motor 31 that penetrates into the mounting disk 2. A transmission gear 11 meshing with the driving gear 22 is fixedly installed on the outer wall of the limiting disk 9. A side channel for the filter part to slide out is provided on the side wall of the housing 1, and a door panel 21 is provided in the side channel;

[0043] A firing part is further provided in the housing 1. When the card slot 10 rotates to communicate with the side channel, the firing part ejects the filter part from the card slot 10.

[0044] According to the above embodiments, when the reduction motor 31 drives the driving gear 22 to drive the limiting disk 9 and the transmission gear 11 to rotate together, specifically referring to Figure 6 , the notch of the card slot 10 is aligned with the door panel 21, that is, when the filter part is in the side channel provided on the side wall of the housing 1 for the filter part to slide out, the firing part ejects the filter part from the card slot 10, so that the removed filter part moves along the side channel and passes through the door panel 21 to reach the outside of the housing 1, completing the disassembly of the waste filter part.

[0045] In this way, through the cooperation of the firing part and the rotation of the limiting disk 9, the filter part and the filter cotton 15 contaminated with too much dirt can be quickly disassembled and discharged from the housing 1, facilitating the replacement of the filter part.

[0046] Further, the firing part includes a special-shaped cavity 19 opened in the housing 1 and located on the side of the limit disk 9. An installation hole is opened in the limit disk 9, and a firing pin 16 is slidably installed in the installation hole. A compression spring 18 that applies a force to move the firing pin 16 closer to the limit disk 9 is installed between the firing pin 16 and the installation hole. One end of the firing pin 16 extending into the special-shaped cavity 19 is fixedly connected with an elastic pin 17. A sliding groove 20 for the elastic pin 17 to insert and slide is opened on the inner wall of the special-shaped cavity 19. The sliding groove 20 is composed of two arc-shaped slides that are farther and farther away from the center of the limit disk 9 in the sliding direction of the elastic pin 17 and a slide that coincides with the radius line of the limit disk 9 connected end to end. And each section of the slide gradually becomes shallower in the sliding direction of the elastic pin 17. A sliding groove 30 for the elastic pin 17 to slide along the telescopic direction of the air cylinder 7 is also opened on the inner wall of the housing 1.

[0047] According to the above embodiment, a specific embodiment of the firing part is provided. Specifically, refer to Figure 6 and Figure 9 , when the reduction motor 31 drives the driving gear 22 to drive the limit disk 9 and the transmission gear 11 to rotate together, it will drive the elastic pin 17 to slide in the outermost arc-shaped slide, and at the same time compress the compression spring 18. When the limit disk 9 rotates counterclockwise by 90 degrees, that is, when the card slot 10 rotates to communicate with the side channel, at this time the elastic pin 17 moves into the slide that coincides with the radius line of the limit disk 9, and under the action of the compression spring 18, it quickly approaches the fixed ring 14 until the firing pin 16 hits the fixed ring 14, and the filtering part is ejected from the card slot 10. Subsequently, the reduction motor 31 drives the driving gear 22 to drive the limit disk 9 and the transmission gear 11 to rotate 90 degrees in the reverse direction to reset, and at the same time drives the elastic pin 17 to slide and reset along the arc-shaped slide close to the fixed ring 14, and the firing pin 16 is pulled back to Figure 6 state, and the compression spring 18 also begins to be gradually compressed to prevent the firing pin 16 from blocking the fixed ring 14 subsequently installed in the card slot 10 or making it unable to be completely stuck in. Finally, a new filtering part (i.e., the fixed ring 14) is reinstalled in the card slot 10, and the quick disassembly and installation of the filtering part in the limit disk 9 can be completed.

[0048] In this way, through the sliding of the elastic pin 17 in the sliding groove 20 in cooperation with the rotation of the limit disk 9, the discarded filtering part can be quickly ejected from the housing 1, so that when too many particles or dust accumulate on the filter cotton 15, it can be quickly disassembled and replaced, avoiding the blockage of the air flow caused by the filter cotton 15 being used for too long and resulting in the device idling and jamming.

[0049] It is worth mentioning that since each section of the slide in the sliding groove 20 gradually becomes shallower in the sliding direction of the elastic pin 17, the elastic pin 17 can only slide unidirectionally in the sliding groove 20, preventing the sliding direction of the elastic pin 17 from changing and causing the firing pin 16 to be unable to eject the discarded filtering part out of the housing 1.

[0050] Furthermore, a bottom box 32 is fixedly connected to the bottom of the housing 1. A top plate 23 is slidably installed in the bottom box 32. A spring 24 is provided between the top plate 23 and the inner bottom wall of the bottom box 32. The sliding ring 8 is tangent to the limiting disc 9.

[0051] According to the above embodiments, when the striker 16 hits the fixed ring 14 in the limiting disc 9 and the filtering part is ejected from the housing 1, the reduction motor 31 drives the driving gear 22 to drive the transmission gear 11 and the limiting disc 9 to reset. At this time, the spring 24 in the bottom box 32 pushes the top plate 23 to drive the filtering part in the bottom box 32 to move up into the limiting disc 9, completing the automatic replacement of the filtering part and realizing the rapid replacement of the filter cotton 15, solving the pain points of replacing the filter cotton 15 at the present stage, reducing the number and duration of the device shutdown for maintenance, and reducing the use cost of the device.

[0052] It is worth mentioning that since the sliding ring 8 is tangent to the limiting disc 9, when the sliding ring 8 slides in the housing 1 following the limiting disc 9, the sliding ring 8 can replace the fixed ring 14 in the limiting disc 9 to limit the lower filtering part, preventing the fixed ring 14 on one side of the lower filtering part from tilting due to the upward limiting force loss and being pushed by the lower top plate 23, which hinders the reset of the limiting disc 9.

[0053] Furthermore, a laser emitter 27 and a laser receiver 28 whose diameter lines coincide with the sliding ring 8 are fixedly installed in the groove on the inner wall of the installation frame 6. The laser receiver 28 is electrically connected to the air cylinder 7. An elastic net 26 is also fixedly installed on the inner wall of the installation frame 6. A light-blocking strip 29 is fixedly installed at the center of the elastic net 26.

[0054] According to the above embodiments, when the filter cotton 15 is in state one, the gas filtered by the filter cotton 15 will enter the installation frame 6 through the sliding ring 8. At this time, the elastic net 26 fixed on the inner wall of the installation frame 6 will expand towards the installation frame 6 under the influence of the air flow. For details, see Figure 8 At this time, the light-blocking strip 29 cannot prevent the laser receiver 28 from receiving the laser signal from the laser emitter 27. As the gas in the container decreases to a certain extent, the gas passing through the filter cotton 15 gradually decreases, causing the expansion degree of the elastic net 26 to decrease, and the light-blocking strip 29 to move towards the laser receiver 28. When the laser receiver 28 cannot receive the laser signal from the laser emitter 27, the air cylinder 7 is driven through the telecommunication connection to switch the filter cotton 15 to state two.

[0055] In this way, the detection of the remaining gas volume in the container can be completed by the cooperation of the laser receiver 28 and the light-blocking strip 29, enabling the device to automatically complete the state switching of the filter cotton 15 when the suction force decreases, meeting the different requirements for gas filtration in different suction stages, and thus improving the filtering effect and vacuum limit of the device.

[0056] Further, the side wall of the card slot 10 is provided with an elastic buckle.

[0057] According to the above embodiments, when the driving gear 11 drives the limiting disc 9 to rotate, the fixing ring 14 in the card slot 10 closely abuts against the lower filtering part and the top plate 23 to provide a supporting force. Specifically, refer to Figure 7 , during the rotation process, the upper fixed filtering part and the lower filtering part will be separated from each other, so that the filtering part in the card slot 10 has slipped out of the card slot 10 before the ejector pin 16 hits the fixing ring 14 and enters the side channel opened on the side wall of the housing 1 for the filtering part to slide out, so that the ejector pin 16 cannot eject the filtering part out of the housing 1, causing an obstruction to the replacement of the filtering part next time.

[0058] Further, the length of the sliding groove 30 is greater than the sliding distance of the elastic pin 17.

[0059] According to the above embodiments, since the air cylinder 7 will push the fixing ring 14 and the elastic pin 17 inside the fixing ring 14 to slide together, in order to prevent the elastic pin 17 from obstructing the sliding of the fixing ring 14, resulting in the inability to normally compress the filter cotton 15, causing the device to jam and reducing the filtering accuracy of the filter cotton 15 at the same time, the present invention sets the length of the sliding groove 30 to be greater than the sliding distance of the elastic pin 17 to meet the sliding requirement of the fixing ring 14.

[0060] Further, plastic meshes for limiting the filter cotton 15 are fixedly installed in both fixing rings 14.

[0061] According to the above embodiments, since the air cylinder 7 compresses the filter cotton 15 when pushing the fixing ring 14 to slide, at this time the filter cotton 15 may expand to both sides. By fixedly installing plastic meshes on both sides of the fixing ring 14 to limit the filter cotton 15, it is avoided that the filter cotton 15 expands to both sides, resulting in insufficient density of the compressed filter cotton 15 and being unable to intercept high-density particulate matters or dust at high speed, resulting in reduced filtering accuracy.

[0062] The standard parts used in this embodiment can be directly purchased from the market, and the non-standard structural components described in the specification and drawings can also be directly processed according to the existing common technical knowledge without any doubt. At the same time, the connection methods of each component adopt the mature conventional means in the existing technology, and the machines, parts and equipment all adopt the conventional models in the existing technology, so no specific description will be made here.

[0063] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A gas filtration device for a vacuum pump in front, comprising a housing and an air outlet formed on the side wall of the housing, characterized in that: On both sides of the housing, an installation disk and a motor are respectively fixedly installed. Inside the housing, there is an installation frame. The part of the main shaft of the motor that penetrates into the housing and the installation frame is fixedly connected with a rotating shaft. Multiple rows of fins are distributed on the side wall of the rotating shaft. The fins are alternately composed of fixed fins and rotating fins with opposite directions. On the side wall of the installation disk, an air inlet pipe that can communicate with the installation frame is installed. A filtering part for filtering gas is arranged in the pipeline between the air inlet pipe and the installation frame. The filtering part includes filter cotton, and the filter cotton has two states. State one: the filter cotton is in a compressed state, improving the filtering accuracy and increasing the air resistance. State two: the filter cotton is in an extended state, reducing the filtering accuracy and decreasing the air resistance. The filtering part includes two fixing rings that can be installed in the pipeline between the air inlet pipe and the installation frame. A corrugated pipe is connected between the two fixing rings, and the filter cotton is fixedly installed between the two fixing rings. Two limiting disks are rotatably installed on the inner wall of the housing. On the opposite surfaces of the two limiting disks, clamping grooves into which the fixing rings can be inserted are opened. And after the fixing rings are inserted into the clamping grooves, they are in an inscribed state with the limiting disks. A plurality of elastic telescopic rods are also fixedly connected between the two limiting disks. On the side of one of the limiting disks, there is a cylinder fixedly installed on the inner wall of the housing. The end of the driving shaft of the cylinder abuts against the side wall of the limiting disk and can slide on the side wall of the limiting disk. One side of the limiting disk is fixedly connected with a sliding ring that can slide inside the housing. A reduction motor is fixedly installed on the side wall of the installation disk. The part of the main shaft of the reduction motor that penetrates into the installation disk is fixedly connected with a driving gear. A transmission gear meshing with the driving gear is fixedly installed on the outer wall of the limiting disk. A side channel through which the filtering part can slide out is opened on the side wall of the housing, and a door plate is arranged in the side channel. There is also a firing part inside the housing. When the clamping groove rotates to communicate with the side channel, the firing part ejects the filtering part from the clamping groove. The firing part includes a special-shaped cavity opened inside the housing and located on the side of the limiting disk. An installation hole is opened in the limiting disk, and a firing pin is slidably installed in the installation hole. A compression spring that applies a force to move the firing pin closer to the limiting disk is installed between the firing pin and the installation hole. One end of the firing pin extending into the special-shaped cavity is fixedly connected with an elastic pin. A sliding groove into which the elastic pin can be inserted and slide is opened on the inner wall of the special-shaped cavity. The sliding groove is composed of two arc-shaped sliding tracks that are getting farther and farther away from the center of the limiting disk in the sliding direction of the elastic pin and a sliding track that coincides with the radius line of the limiting disk connected end to end. And each section of the sliding track gradually becomes shallower in the sliding direction of the elastic pin. A sliding groove through which the elastic pin can slide along the telescopic direction of the cylinder is also opened on the inner wall of the housing.

2. The pre-vacuum pump gas filtration device according to claim 1, wherein: The bottom of the housing is fixedly connected with a bottom box. A top plate is slidably installed inside the bottom box. A spring is arranged between the top plate and the inner bottom wall of the bottom box. The sliding ring is tangent to the limiting disk.

3. The pre-vacuum pump gas filtration device according to claim 2, characterized in that: A laser emitter and a laser receiver that coincide with the diameter line of the sliding ring are fixedly installed in the groove on the inner wall of the installation frame. And the laser receiver is electrically connected with the cylinder. An elastic net is also fixedly installed on the inner wall of the installation frame, and a light-blocking strip is fixedly installed at the center of the elastic net.

4. The pre-vacuum pump gas filtration device according to claim 3, characterized in that: An elastic buckle is arranged on the side wall of the clamping groove.

5. The pre-vacuum pump gas filtration device according to claim 4, characterized in that: The length of the sliding groove is greater than the sliding distance of the elastic pin.

6. The pre-vacuum pump gas filtration device according to claim 5, characterized in that: Plastic meshes for limiting the filter cotton are fixedly installed in both of the two fixing rings.

Images