Variable frequency energy-saving screw vacuum pump

Abstract

This invention discloses a variable frequency energy-saving screw vacuum pump, relating to the field of screw vacuum pump technology. It includes an energy-saving device, a pumping chamber, an air inlet, an exhaust port, and a drive component. The drive component drives the male and female screws within the pumping chamber to rotate. The pumping chamber compresses and discharges air, gradually evacuating the working space into a vacuum. It can work in conjunction with a frequency converter. During the operation of the screw vacuum pump, the compression ratio and bypass channel opening can be dynamically adjusted according to the changing pumping requirements at different process stages, allowing it to operate within a more ideal working range. During the vacuum pump start-up and shutdown transition phase, the bypass channel is opened and the compression ratio is reduced to minimize wasted work. During the pumping phase, the bypass channel is closed, and a lower compression ratio reduces energy loss, thus achieving energy savings. During the stable operation phase, the compression ratio is increased to ensure pumping efficiency, thereby achieving adaptive matching for different operating conditions.

Description

Technical Field

[0001] This invention relates to the field of screw vacuum pump technology, specifically a variable frequency energy-saving screw vacuum pump. Background Technology

[0002] Screw vacuum pumps, as a common type of dry vacuum equipment, are a type of variable displacement pump widely used in semiconductor manufacturing, chemical industry and other fields to extract gases and establish a stable vacuum environment. They have advantages such as no oil pollution, stable operation and strong adaptability, and can meet the process requirements with high cleanliness requirements.

[0003] Most existing screw vacuum pumps are driven by fixed-speed motors. However, in practical applications, the requirements for vacuum level and pumping rate often vary greatly at different process stages. The traditional fixed-speed operation mode cannot flexibly adjust the speed according to the actual working conditions, which can easily lead to energy waste. Summary of the Invention

[0004] The purpose of this invention is to provide a variable frequency energy-saving screw vacuum pump to solve the problem of energy waste in existing vacuum pumps.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a chamber is included, within which a pumping chamber is provided. One end of the pumping chamber has an air inlet, and the other end has an exhaust outlet. An energy-saving device is installed on the outside of the pumping chamber. A drive unit is installed on one side of the chamber and is connected to a control system. The drive unit includes a motor connected to a frequency converter. The energy-saving device reduces the load and prevents the motor from overheating during the initial vacuum pumping phase, and ensures pumping efficiency during the stable operating phase.

[0006] The energy-saving device includes a variable compression ratio assembly. A bypass channel is provided on the pumping chamber, with one end of the bypass channel located at the air inlet and the other end at the air outlet. A bypass assembly is slidably installed inside the bypass channel. During the vacuum pump start-up and shutdown phase, the bypass channel is opened, allowing air to be drawn directly from the air inlet to the air outlet. The variable compression ratio assembly moves to a small compression ratio. During the pumping phase, the bypass channel is gradually closed, and the variable compression ratio assembly remains at a small compression ratio to prevent over-compression and reduce unnecessary consumption. Then, the compression ratio is slowly increased to ensure pumping efficiency, allowing the vacuum pump to gradually reach a high vacuum environment. During the stable operation phase, the variable compression ratio assembly is at a large compression ratio to maintain the vacuum level. Energy saving is achieved by adjusting the speed through a frequency converter.

[0007] The variable compression ratio assembly includes a sliding sleeve that slides outside the pumping chamber. A trigger element is mounted on one side of the pumping chamber, with one end of the trigger element attached to the sliding sleeve. The trigger element is connected to the exhaust port via a pipe, and a damping box is mounted on one side of the trigger element. The trigger element senses the pressure at the intake port, thereby causing the sliding sleeve to slide outside the pumping chamber. By changing the exhaust timing, the compression ratio is altered, and the damping box reduces the oscillations during the sliding sleeve's movement.

[0008] The bypass assembly includes a centrifugal element that rotates within the chamber. An adjustment channel is provided on the bypass passage, and a plunger is slidably installed within the adjustment channel. An adjustment piston is mounted on one side of the plunger. The bypass passage is opened and closed by the centrifugal element according to its rotational speed. The adjustment piston senses the pressure difference between the inlet and outlet. When a blockage occurs inside the vacuum pump, causing an extremely large pressure difference, the bypass passage is quickly opened to release pressure and prevent damage to the vacuum pump.

[0009] The sliding sleeve includes a main body that slides outside the pumping chamber. The main body has a first outlet groove and a second outlet groove. One side of the first outlet groove communicates with the pumping chamber, and the other side communicates with the exhaust port. One side of the second outlet groove communicates with a bypass channel, and the other side communicates with the pumping chamber. When the vacuum pump starts, the main body is located away from the motor. At this time, the distance between the first outlet groove and the inlet is closest, reducing the gas compression time and allowing the airflow to exit the exhaust port more quickly, thus reducing the compression ratio and energy consumption. When the vacuum pump is operating stably, the main body gradually moves closer to the motor, gradually extending the airflow compression time and allowing the airflow to exit the exhaust port more slowly, increasing the compression ratio and ensuring operational efficiency.

[0010] The triggering element includes a trigger housing, which is installed on the outside of the pumping chamber. A movable plate is slidably mounted inside the trigger housing. An air intake pipe is installed between the trigger housing and the movable plate, communicating with the air inlet. An extension plate is mounted on one side of the movable plate, and a connecting plate is mounted on one side of the extension plate. The connecting plate is mounted on the sliding sleeve body. A first elastic element is mounted on the other side of the movable plate, with one end of the first elastic element mounted on the trigger housing. The first elastic element includes a first spring. When the vacuum pump starts, the air inlet pressure is high, pushing the movable plate away from the motor. The movable plate then moves the extension plate away from the motor, the extension plate moves the connecting plate away from the motor, and the connecting plate moves the sliding sleeve body away from the motor. When the vacuum pump pumps air, the air inlet pressure gradually decreases. The first spring stretches, causing the movable plate to move closer to the motor. The movable plate then moves the extension plate closer to the motor, the extension plate moves the connecting plate closer to the motor, and the connecting plate moves the sliding sleeve body closer to the motor.

[0011] The damping box includes a damping shell, which is installed on the outside of the pumping chamber. A damping tube and a one-way tube are installed inside the damping shell. One end of the damping tube and the one-way tube is installed on the trigger shell. A second elastic element is installed inside the one-way tube. A ball plug is installed on one side of the second elastic element. The ball plug slides inside the one-way tube. An outlet is provided on the one-way tube. The second elastic element includes a second spring. The space between the moving plate and the damping housing is filled with damping oil. When the moving plate moves away from the motor, it squeezes the damping oil to flow towards the damping housing. The damping oil pushes the ball plug to move away from the first spring. At this time, the second spring is compressed until the damping oil flows out from the outlet. Because the outlet is large, the damping on the moving plate is small, allowing the moving plate to move quickly away from the motor. At this time, the sliding sleeve body moves quickly to a position with a small compression ratio. When the moving plate moves towards the motor, the damping oil in the damping housing is drawn into the trigger housing. The ball plug blocks the one-way tube, and the damping oil can only flow out from the damping tube. Because the damping tube is small, the damping on the moving plate is large, reducing the oscillation when the sliding sleeve body moves.

[0012] The centrifugal element includes a drive rod that rotates within the chamber. A support ring is mounted on the drive rod, and a rotating rod is rotatably mounted on the support ring. A centrifugal ball is mounted on one side of the rotating rod. A connecting rod is rotatably mounted on the rotating rod, and a linkage ring is rotatably mounted on one side of the connecting rod. A sliding ring is slidably mounted on the drive rod, and the linkage ring rotates on the sliding ring. A connecting plate is rotatably mounted on one side of the sliding ring, and one side of the connecting plate rotates on the plunger. When the female rotor rotates, it drives the drive belt to rotate, which in turn drives the drive rod to rotate. The drive rod drives the support ring to rotate, which in turn drives the rotating rod to rotate. The rotating rod drives the connecting rod to rotate on the sliding ring. When the speed of the female rotor increases, the centrifugal ball causes the rotating rod to swing away from the drive rod. The rotating rod then causes the connecting rod to swing away from the drive rod. The drive rod causes the sliding ring to slide closer to the support ring on the drive rod. The sliding ring then drives the connecting plate to rotate, and the connecting plate causes the plunger cylinder to slide away from the drive rod within the adjustment channel.

[0013] The plunger includes a plunger cylinder that slides within an adjustment channel. A first through groove is provided on the plunger cylinder. A connecting plate rotates on the plunger cylinder. A third elastic element is installed at one end of the plunger cylinder, and one end of the third elastic element is installed on the adjustment channel. An inner cylinder is slidably installed inside the plunger cylinder. A fourth elastic element is installed at one end of the inner cylinder, and one end of the fourth elastic element is installed inside the plunger cylinder. A second through groove is provided on the inner cylinder. The fourth elastic element includes a fourth spring. When the vacuum pump is not started, the second through groove is located within the bypass channel, allowing gas at the inlet to directly enter the exhaust port from the bypass channel, reducing the pressure during startup. As the rotational speed of the female rotor gradually increases, the plunger cylinder moves away from the drive rod, gradually blocking the bypass channel until the first through groove is located within the bypass channel. At this point, the inner cylinder blocks the first through groove, allowing gas to enter the exhaust port through the compression chamber, ensuring efficient pumping.

[0014] The regulating piston includes a piston housing installed within an regulating channel. A first connecting pipe and a second connecting pipe are mounted on the piston housing. The first connecting pipe connects to the air inlet, and the second connecting pipe connects to the exhaust port. A piston plate is slidably mounted inside the piston housing. A piston rod is mounted on one side of the piston plate, and a push plate is mounted on one side of the piston rod. When the vacuum pump starts, the pressure difference between the air inlet and exhaust port is small, and the piston plate is in its initial position. When the vacuum pump pumps air, because the pressure at the exhaust port is greater than the pressure at the air inlet, the piston plate moves towards the first connecting pipe. The piston plate drives the piston rod to move towards the inner cylinder, and the piston rod drives the push plate to move towards the inner cylinder until the push plate abuts against the inner cylinder. When a blockage occurs inside the vacuum pump, the pressure difference between the air inlet and exhaust port becomes extremely large. The piston plate continues to move towards the inner cylinder, and the piston plate drives the push plate to continue moving towards the inner cylinder. The push plate presses the inner cylinder, causing it to slide within the plunger cylinder until the second through groove aligns with the first through groove, allowing gas to pass through the bypass channel for pressure relief, preventing damage to the vacuum pump.

[0015] The pumping chamber includes a compression chamber with an outlet. A female rotor and a male rotor are rotatably mounted inside the compression chamber. The female rotor is mounted on a drive unit and connected to a transmission rod via a transmission belt. A first gear is mounted at one end of the female rotor, and a second gear is mounted at one end of the male rotor. The first and second gears mesh. When the vacuum pump starts, the motor drives the female rotor to rotate, which in turn drives the first gear, which in turn drives the second gear, which in turn drives the male rotor. The meshing rotation of the female and male rotors gradually compresses the gas entering through the inlet.

[0016] One side of the first air outlet groove is connected to the air outlet, and the other side of the second air outlet groove is connected to the compression chamber.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention employs an energy-saving device that can work in conjunction with a frequency converter. During the operation of the screw vacuum pump, the compression ratio and bypass channel opening can be dynamically adjusted according to the changes in pumping demand at different process stages, allowing it to operate within a more ideal working range. During the vacuum pump start-up and shutdown transition phase, the bypass channel is opened and the compression ratio is reduced to minimize wasted work. During the pumping phase, the bypass channel is closed, and a lower compression ratio reduces energy loss, thereby achieving energy saving. During the stable operation phase, the compression ratio is increased to ensure pumping efficiency, thus achieving adaptive matching for different operating conditions. Attached Figure Description

[0018] Figure 1 This is a perspective view of the screw vacuum pump of the present invention; Figure 2 This is a schematic diagram of the internal structure of the screw vacuum pump of the present invention; Figure 3 This is a schematic diagram of the internal structure of the variable compression component of the present invention; Figure 4 This is a perspective view of the bypass component of the present invention; Figure 5 This is a perspective view of the sliding sleeve body of the present invention; Figure 6 This is a cross-sectional view of the trigger element and damping box of the present invention; Figure 7 for Figure 4 A magnified view of a portion of region A in the middle; Figure 8 This is an exploded view of the plunger of the present invention; Figure 9 This is a cross-sectional view of the adjusting piston of the present invention; Figure 10 This is a schematic diagram of the interior of the pumping chamber of the present invention.

[0019] In the diagram: 1. Energy-saving device; 11. Variable compression ratio assembly; 111. Sliding sleeve; 1111. Sliding sleeve body; 1112. First air outlet groove; 1113. Second air outlet groove; 112. Trigger element; 1121. Trigger housing; 1122. Moving plate; 1123. Extension plate; 1124. First elastic element; 113. Damping box; 1131. Damping housing; 1132. One-way tube; 1133. Damping tube; 1134. Ball plug; 1135. Second elastic element; 1136. Outlet; 12. Bypass assembly; 121. Centrifugal element; 1211. Transmission rod; 1212. Support ring; 1213. Rotating rod; 1214. 1215. Connecting rod; 1216. Sliding ring; 1217. Linking ring; 1218. Connecting plate; 122. Plunger; 1221. Plunger cylinder; 1222. First through groove; 1223. Inner cylinder; 1224. Second through groove; 1225. Fourth elastic element; 123. Adjusting piston; 1231. Piston shell; 1232. First connecting pipe; 1233. Second connecting pipe; 1234. Piston plate; 1235. Piston rod; 13. Bypass channel; 2. Pumping chamber; 21. Compression chamber; 22. Female rotor; 23. Male rotor; 24. First gear; 25. Second gear; 26. Air outlet; 3. Air inlet; 4. Exhaust port; 5. Driving component. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example: Figures 1-10 As shown, the present invention provides a technical solution including a chamber, a pumping chamber 2 is provided inside the chamber, an air inlet 3 is provided at one end of the pumping chamber 2, an exhaust port 4 is provided at the other end of the pumping chamber 2, an energy-saving device 1 is installed on the outside of the pumping chamber 2, and a drive component 5 is installed on one side of the chamber. The drive component 5 is connected to a control system. The drive component 5 includes a motor, which is connected to a frequency converter. The energy-saving device 1 reduces the load and prevents the motor from overheating during the initial stage of vacuum pumping, and ensures pumping efficiency during the stable operation stage.

[0022] The energy-saving device 1 includes a variable compression ratio assembly 11. A bypass channel 13 is provided on the pumping chamber 2. One end of the bypass channel 13 is located at the air inlet 3, and the other end is located at the exhaust port 4. A bypass assembly 12 is slidably installed inside the bypass channel 13. During the vacuum pump start-up and shutdown phase, the bypass channel 13 is opened, allowing air to be drawn directly from the air inlet 3 to the exhaust port 4. The variable compression ratio assembly 11 moves to a small compression ratio. During the pumping phase, the bypass channel 13 is gradually closed, and the variable compression ratio assembly 11 remains at a small compression ratio to prevent over-compression and reduce unnecessary consumption. Then, the compression ratio is slowly increased to ensure pumping efficiency, allowing the vacuum pump to gradually reach a high vacuum environment. During the stable operation phase, the variable compression ratio assembly 11 is at a large compression ratio to maintain the vacuum level. Energy saving is achieved by adjusting the speed through a frequency converter.

[0023] The variable compression ratio assembly 11 includes a sliding sleeve 111 that slides outside the pumping chamber 2. A trigger element 112 is mounted on one side of the pumping chamber 2, with one end of the trigger element 112 mounted on the sliding sleeve 111. The trigger element 112 is connected to the exhaust port 4 via a pipe, and a damping box 113 is mounted on one side of the trigger element 112. The trigger element 112 senses the pressure at the intake port 3, thereby causing the sliding sleeve 111 to slide outside the pumping chamber 2. By changing the exhaust time, the compression ratio is changed, and the damping box 113 reduces the oscillation of the sliding sleeve 111 during movement.

[0024] The bypass assembly 12 includes a centrifugal element 121 that rotates within the chamber. An adjustment channel is provided on the bypass channel 13, and a plunger 122 is slidably mounted within the adjustment channel. An adjustment piston 123 is mounted on one side of the plunger 122. The bypass channel 13 is opened and closed by the centrifugal element 121 according to its rotational speed. The pressure difference between the inlet 3 and the outlet 4 is sensed by the adjustment piston 123. When a blockage occurs inside the vacuum pump, causing a very large pressure difference, the bypass channel 13 is quickly opened to release pressure and prevent damage to the vacuum pump.

[0025] The sliding sleeve 111 includes a sliding sleeve body 1111, which slides outside the pumping chamber 2. The sliding sleeve body 1111 is provided with a first outlet groove 1112 and a second outlet groove 1113. One side of the first outlet groove 1112 communicates with the outlet 26, and the other side communicates with the exhaust port 4. One side of the second outlet groove 1113 communicates with the bypass channel 13, and the other side communicates with the compression chamber 21. When the vacuum pump starts, the sliding sleeve body 1111 is located away from the motor. At this time, the first outlet groove 1112 is closest to the inlet 3, reducing the gas compression time and allowing the airflow to exit from the exhaust port 4 more quickly, thus reducing the compression ratio and energy consumption. When the vacuum pump is working stably, the sliding sleeve body 1111 gradually moves closer to the motor, gradually extending the airflow compression time, allowing the airflow to exit from the exhaust port 4 more slowly, increasing the compression ratio and ensuring working efficiency.

[0026] The trigger element 112 includes a trigger housing 1121, which is installed on the outside of the pumping chamber 2. A movable plate 1122 is slidably installed inside the trigger housing 1121. An air intake pipe is installed between the trigger housing 1121 and the movable plate 1122, and the air intake pipe is connected to the air inlet 3. An extension plate 1123 is installed on one side of the movable plate 1122, and a connecting plate is installed on one side of the extension plate 1123. The connecting plate is installed on the sliding sleeve body 1111. A first elastic member 1124 is installed on the other side of the movable plate 1122, and one end of the first elastic member 1124 is installed on the trigger housing 1121. The first elastic element 1124 includes a first spring. When the vacuum pump starts, the pressure at the air inlet 3 is relatively high, which pushes the moving plate 1122 to move away from the motor. The moving plate 1122 drives the extension plate 1123 to move away from the motor. The extension plate 1123 drives the connecting plate to move away from the motor. The connecting plate drives the sliding sleeve body 1111 to move away from the motor. When the vacuum pump pumps air, the pressure at the air inlet 3 gradually decreases. The first spring stretches and drives the moving plate 1122 to move closer to the motor. The moving plate 1122 drives the extension plate 1123 to move closer to the motor. The extension plate 1123 drives the connecting plate to move closer to the motor. The connecting plate drives the sliding sleeve body 1111 to move closer to the motor.

[0027] The damping box 113 includes a damping housing 1131, which is installed on the outside of the pumping chamber 2. A damping tube 1133 and a one-way tube 1132 are installed inside the damping housing 1131. One end of the damping tube 1133 and the one-way tube 1132 is installed on the trigger housing 1121. A second elastic element 1135 is installed inside the one-way tube 1132. A ball plug 1134 is installed on one side of the second elastic element 1135. The ball plug 1134 slides inside the one-way tube 1132. An outlet 1136 is provided on the one-way tube 1132. The second elastic element 1135 includes a second spring. Damping oil fills the space between the moving plate 1122 and the damping housing 1131. When the moving plate 1122 moves away from the motor, it compresses the damping oil, causing it to flow towards the damping housing 1131. The damping oil pushes the ball plug 1134 away from the first spring, compressing the second spring until the damping oil flows out from the outlet 1136. Because the outlet 1136 is relatively large, the damping experienced by the moving plate 1122 is small, causing the moving plate 1122 to move more smoothly. The moving plate 1122 can quickly move to a position away from the motor. At this time, the sliding sleeve body 1111 quickly moves to a position with a small compression ratio. When the moving plate 1122 moves towards the motor, the damping oil in the damping housing 1131 is drawn into the trigger housing 1121. The ball plug 1134 blocks the one-way tube 1132, and the damping oil can only flow out from the damping tube 1133. Since the damping tube 1133 is small, the moving plate 1122 experiences greater damping, which reduces the oscillation when the sliding sleeve body 1111 moves.

[0028] The centrifugal element 121 includes a transmission rod 1211 that rotates within the chamber. A support ring 1212 is mounted on the transmission rod 1211. A rotating rod 1213 is rotatably mounted on the support ring 1212. A centrifugal ball is mounted on one side of the rotating rod 1213. A connecting rod 1214 is rotatably mounted on the rotating rod 1213. A linkage ring 1216 is rotatably mounted on one side of the connecting rod 1214. A sliding ring 1215 is slidably mounted on the transmission rod 1211. The linkage ring 1216 rotates on the sliding ring 1215. A connecting plate 1217 is rotatably mounted on one side of the sliding ring 1215. One side of the connecting plate 1217 rotates on the plunger 122. When the female rotor 22 rotates, it drives the transmission belt to rotate, which in turn drives the transmission rod 1211 to rotate. The transmission rod 1211 drives the support ring 1212 to rotate, which in turn drives the rotating rod 1213 to rotate. The rotating rod 1213 drives the connecting rod 1214 to rotate, and the connecting rod 1214 drives the connecting ring 1216 to rotate on the sliding ring 1215. When the speed of the female rotor 22 increases, the centrifugal ball drives the rotating rod 1213 to swing away from the transmission rod 1211. The rotating rod 1213 drives the connecting rod 1214 to swing away from the transmission rod 1211. The transmission rod 1211 drives the sliding ring 1215 to slide closer to the support ring 1212 on the transmission rod 1211. The sliding ring 1215 drives the connecting plate 1217 to rotate, and the connecting plate 1217 drives the plunger cylinder 1221 to slide away from the transmission rod 1211 within the adjustment channel.

[0029] The plunger 122 includes a plunger cylinder 1221, which slides within an adjustment channel. A first through groove 1222 is provided on the plunger cylinder 1221. A connecting plate 1217 rotates on the plunger cylinder 1221. A third elastic element is installed at one end of the plunger cylinder 1221, and one end of the third elastic element is installed on the adjustment channel. An inner cylinder 1223 is slidably installed inside the plunger cylinder 1221. A fourth elastic element 1225 is installed at one end of the inner cylinder 1223, and one end of the fourth elastic element 1225 is installed inside the plunger cylinder 1221. A second through groove 1224 is provided on the inner cylinder 1223. The fourth elastic element 1225 includes a fourth spring. When the vacuum pump is not started, the second through groove 1224 is located in the bypass channel 13, which facilitates the gas at the inlet 3 to directly enter the exhaust port 4 from the bypass channel 13, reducing the pressure during startup. When the speed of the female rotor 22 gradually increases, the plunger cylinder 1221 moves away from the transmission rod 1211 and gradually blocks the bypass channel 13 until the first through groove 1222 is located in the bypass channel 13. At this time, the inner cylinder 1223 blocks the first through groove 1222, allowing the gas to enter the exhaust port 4 through the compression chamber 21, ensuring the efficiency of pumping.

[0030] The adjusting piston 123 includes a piston housing 1231, which is installed in the adjusting channel. A first connecting pipe 1232 and a second connecting pipe 1233 are installed on the piston housing 1231. The first connecting pipe 1232 is connected to the air inlet 3, and the second connecting pipe 1233 is connected to the exhaust port 4. A piston plate 1234 is slidably installed inside the piston housing 1231. A piston rod 1235 is installed on one side of the piston plate 1234, and a push plate is installed on one side of the piston rod 1235. When the vacuum pump starts, the pressure difference between the inlet 3 and the outlet 4 is small, and the piston plate 1234 is in its initial position. When the vacuum pump pumps air, because the pressure at the outlet 4 is greater than the pressure at the inlet 3, the piston plate 1234 moves towards the first connecting pipe 1232. The piston plate 1234 drives the piston rod 1235 to move towards the inner cylinder 1223. The piston rod 1235 drives the push plate to move towards the inner cylinder 1223 until the push plate abuts against the inner cylinder 1223. When the vacuum pump is blocked, the pressure difference between the inlet 3 and the outlet 4 becomes extremely large. The piston plate 1234 continues to move towards the inner cylinder 1223. The piston plate 1234 drives the push plate to continue moving towards the inner cylinder 1223. The push plate presses the inner cylinder 1223 to slide inside the plunger cylinder 1221 until the second through groove 1224 is aligned with the first through groove 1222, allowing gas to pass through the bypass channel 13 to release pressure and prevent damage to the vacuum pump.

[0031] The pumping chamber 2 includes a compression chamber 21 with an outlet 26. A female rotor 22 and a male rotor 23 are rotatably mounted inside the compression chamber 21. The female rotor 22 is mounted on the drive unit 5 and connected to the transmission rod 1211 via a transmission belt. A first gear 24 is mounted at one end of the female rotor 22, and a second gear 25 is mounted at one end of the male rotor 23. The first gear 24 and the second gear 25 mesh. When the vacuum pump starts, the motor drives the female rotor 22 to rotate, which in turn drives the first gear 24 to rotate, which in turn drives the second gear 25 to rotate, and the second gear 25 drives the male rotor 23 to rotate. The meshing rotation of the female rotor 22 and the male rotor 23 gradually compresses the gas entering through the inlet 3.

[0032] Working principle of the invention: When the vacuum pump starts, the motor drives the female rotor 22 to rotate, which in turn drives the first gear 24 to rotate. The first gear 24 then drives the second gear 25 to rotate, and the second gear 25 drives the male rotor 23 to rotate. The female rotor 22 and the male rotor 23 mesh and rotate, gradually compressing the gas entering through the inlet 3. The second through slot 1224 is located within the bypass channel 13, allowing the gas at the inlet 3 to directly enter the exhaust port 4 through the bypass channel 13, reducing the pressure during startup. Due to the high pressure at the inlet 3, the moving plate 1122 is pushed to move away from the motor. 2. The extension plate 1123 is moved away from the motor. The extension plate 1123 moves the connecting plate away from the motor. The connecting plate moves the sliding sleeve body 1111 away from the motor. The moving plate 1122 squeezes the damping oil to flow towards the damping housing 1131. The damping oil pushes the ball plug 1134 away from the first spring. At this time, the second spring is compressed until the damping oil flows out from the outlet 1136. Since the outlet 1136 is large, the damping of the moving plate 1122 is small, so the moving plate 1122 can move quickly to a position away from the motor.

[0033] When the vacuum pump is pumping air, the rotation speed of the female rotor 22 increases, which drives the transmission belt to rotate. The transmission belt drives the transmission rod 1211 to rotate, which in turn increases the rotation speed of the transmission rod 1211. At this time, the centrifugal ball drives the rotating rod 1213 to swing away from the transmission rod 1211. The rotating rod 1213 drives the connecting rod 1214 to swing away from the transmission rod 1211. The transmission rod 1211 drives the sliding ring 1215 to slide on the transmission rod 1211 towards the support ring 1212. The sliding ring 1215 drives the connecting plate 1217 to rotate. The connecting plate 1217 drives the plunger cylinder 1221 to slide away from the transmission rod 1211 in the adjustment channel. The plunger cylinder 1221 moves away from the transmission rod 1211 and gradually blocks the bypass channel 13 until the first through groove 1222 is located in the bypass channel 13. At this time, the inner cylinder 1223 blocks the first through groove 1222, allowing the gas to enter the exhaust port 4 through the compression chamber 21, ensuring the pumping efficiency.

[0034] As the bypass channel 13 gradually closes, the pressure at the air inlet 3 gradually decreases. The first spring stretches and drives the moving plate 1122 to move closer to the motor. The moving plate 1122 drives the extension plate 1123 to move closer to the motor. The extension plate 1123 drives the connecting plate to move closer to the motor. The connecting plate drives the sliding sleeve body 1111 to move closer to the motor. The damping oil in the damping housing 1131 is drawn into the trigger housing 1121. The ball plug 1134 blocks the one-way pipe 1132, and the damping oil can only flow out from the damping pipe 1133. Since the damping pipe 1133 is small, the moving plate 1122 experiences greater damping, which reduces the oscillation when the sliding sleeve body 1111 moves. At the same time, the distance between the first air outlet groove 1112 of the sliding sleeve body 1111 and the air inlet 3 is relatively close, which reduces the gas compression time and allows the airflow to be discharged from the exhaust port 4 more quickly, reducing the compression ratio and reducing energy consumption.

[0035] When the vacuum pump is working stably, as the pressure at the inlet 3 gradually decreases, the sliding sleeve body 1111 gradually moves closer to the motor, and the time for the airflow to enter the exhaust port 4 gradually increases, thus extending the airflow compression time and allowing the airflow to be discharged from the exhaust port 4 more slowly, increasing the compression ratio and ensuring working efficiency. At this time, the energy consumption is adjusted by changing the motor speed through the frequency converter.

[0036] When the vacuum pump becomes blocked, the pressure difference between the inlet 3 and the outlet 4 becomes extremely large. The piston plate 1234 continues to move towards the inner cylinder 1223. The piston plate 1234 drives the push plate to continue moving towards the inner cylinder 1223. The push plate overcomes the elastic force of the fourth spring and pushes the inner cylinder 1223 to slide towards the transmission rod 1211 inside the plunger cylinder 1221 until the second through groove 1224 is aligned with the first through groove 1222. This allows the gas to pass through the bypass channel 13 and the second through groove 1224 into the outlet 4 to release pressure and prevent damage to the vacuum pump.

[0037] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A variable frequency energy saving screw vacuum pump, characterized by: Includes a chamber, in which a pumping chamber (2) is provided, an air inlet (3) is provided at one end of the pumping chamber (2), an exhaust port (4) is provided at the other end of the pumping chamber (2), an energy-saving device (1) is installed on the outside of the pumping chamber (2), a drive unit (5) is installed on one side of the chamber, and the drive unit (5) is connected to the control system. The energy-saving device (1) includes a variable compression ratio component (11), and a bypass channel (13) is provided on the pumping chamber (2). One end of the bypass channel (13) is located at the air inlet (3), and the other end of the bypass channel (13) is located at the exhaust port (4). A bypass component (12) is slidably installed in the bypass channel (13). The variable compression ratio assembly (11) includes a sliding sleeve (111) that slides on the outside of the pumping chamber (2). A trigger element (112) is installed on one side of the pumping chamber (2). One end of the trigger element (112) is installed on the sliding sleeve (111). The trigger element (112) is connected to the exhaust port (4) through a pipe. A damping box (113) is installed on one side of the trigger element (112).

2. The frequency conversion energy saving screw vacuum pump according to claim 1, characterized in that: The bypass assembly (12) includes a centrifugal element (121) that rotates within the chamber. An adjustment channel is provided on the bypass channel (13), and a plunger (122) is slidably installed in the adjustment channel. An adjustment piston (123) is installed on one side of the plunger (122).

3. The variable frequency energy-saving screw vacuum pump according to claim 2, characterized in that: The sliding sleeve (111) includes a sliding sleeve body (1111), which slides on the outside of the pumping chamber (2). The sliding sleeve body (1111) is provided with a first air outlet groove (1112) and a second air outlet groove (1113). One side of the first air outlet groove (1112) is connected to the pumping chamber (2), and the other side of the first air outlet groove (1112) is connected to the exhaust port (4). One side of the second air outlet groove (1113) is connected to the bypass channel (13), and the other side of the second air outlet groove (1113) is connected to the pumping chamber (2).

4. The variable frequency energy-saving screw vacuum pump according to claim 3, characterized in that: The trigger element (112) includes a trigger housing (1121), which is installed on the outside of the pumping chamber (2). A movable plate (1122) is slidably installed inside the trigger housing (1121). An air intake pipe is installed between the trigger housing (1121) and the movable plate (1122), and the air intake pipe is connected to the air inlet (3). An extension plate (1123) is installed on one side of the movable plate (1122), and a connecting plate is installed on one side of the extension plate (1123). The connecting plate is installed on the sliding sleeve body (1111), and a first elastic element (1124) is installed on the other side of the movable plate (1122). One end of the first elastic element (1124) is installed on the trigger housing (1121).

5. The variable frequency energy-saving screw vacuum pump according to claim 4, characterized in that: The damping box (113) includes a damping shell (1131), which is installed on the outside of the pumping chamber (2). A damping tube (1133) and a one-way tube (1132) are installed inside the damping shell (1131). One end of the damping tube (1133) and the one-way tube (1132) is installed on the trigger shell (1121). A second elastic element (1135) is installed inside the one-way tube (1132). A ball plug (1134) is installed on one side of the second elastic element (1135). The ball plug (1134) slides inside the one-way tube (1132). An outlet (1136) is provided on the one-way tube (1132).

6. The variable frequency energy-saving screw vacuum pump according to claim 3, characterized in that: The centrifugal element (121) includes a transmission rod (1211) that rotates within the chamber. A support ring (1212) is mounted on the transmission rod (1211). A rotating rod (1213) is rotatably mounted on the support ring (1212). A centrifugal ball is mounted on one side of the rotating rod (1213). A connecting rod (1214) is rotatably mounted on the rotating rod (1213). A linkage ring (1216) is rotatably mounted on one side of the connecting rod (1214). A sliding ring (1215) is slidably mounted on the transmission rod (1211). The linkage ring (1216) rotates on the sliding ring (1215). A connecting plate (1217) is rotatably mounted on one side of the sliding ring (1215). One side of the connecting plate (1217) rotates on the plunger (122).

7. The variable frequency energy-saving screw vacuum pump according to claim 6, characterized in that: The plunger (122) includes a plunger cylinder (1221), which slides within an adjustment channel. A first through groove (1222) is provided on the plunger cylinder (1221). The connecting plate (1217) rotates on the plunger cylinder (1221). A third elastic element is installed at one end of the plunger cylinder (1221), and one end of the third elastic element is installed on the adjustment channel. An inner cylinder (1223) is slidably installed inside the plunger cylinder (1221). A fourth elastic element (1225) is installed at one end of the inner cylinder (1223), and one end of the fourth elastic element (1225) is installed inside the plunger cylinder (1221). A second through groove (1224) is provided on the inner cylinder (1223).

8. The variable frequency energy-saving screw vacuum pump according to claim 7, characterized in that: The adjusting piston (123) includes a piston housing (1231), which is installed in the adjusting channel. A first connecting pipe (1232) and a second connecting pipe (1233) are installed on the piston housing (1231). The first connecting pipe (1232) is connected to the air inlet (3), and the second connecting pipe (1233) is connected to the exhaust port (4). A piston plate (1234) is slidably installed inside the piston housing (1231). A piston rod (1235) is installed on one side of the piston plate (1234), and a push plate is installed on one side of the piston rod (1235).

9. A variable frequency energy-saving screw vacuum pump according to claim 6, characterized in that: The pumping chamber (2) includes a compression chamber (21), and an air outlet (26) is provided on the compression chamber (21). A female rotor (22) and a male rotor (23) are rotatably installed in the compression chamber (21). The female rotor (22) is installed on the drive component (5). The female rotor (22) is connected to the transmission rod (1211) by a transmission belt. A first gear (24) is installed at one end of the female rotor (22), and a second gear (25) is installed at one end of the male rotor (23). The first gear (24) and the second gear (25) mesh.

10. A variable frequency energy-saving screw vacuum pump according to claim 9, characterized in that: One side of the first air outlet groove (1112) is connected to the air outlet (26), and the other side of the second air outlet groove (1113) is connected to the compression chamber (21).

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