Gap adjusting device of screw vacuum pump and screw vacuum pump

Abstract

The invention provides a screw vacuum pump gap adjusting device and a screw vacuum pump. The screw vacuum pump comprises a pump cavity and a screw rotor, the pump cavity is provided with a first end cover located on the air inlet side and a second end cover located on the air outlet side, and the screw rotor is rotatably arranged in the pump cavity and comprises a rotor shaft and a rotor element arranged on the rotor shaft; the gap adjusting device comprises a gap adjusting plate, a driving assembly, a detection assembly and a controller. The gap adjusting plate is movably arranged on the side, facing the rotor element, of the second end cover, and a gap is formed between the gap adjusting plate and the end face of the rotor element. The driving assembly can drive the gap adjusting plate to reciprocate in the axial direction of the rotor element. The detection assembly can detect working state information of the screw vacuum pump; the controller can control the driving assembly to work according to the working state information. According to the clearance adjusting device, the problem of thermal deformation of the screw rotor can be solved through clearance control, and the performance and stability of the screw vacuum pump are guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of dry screw pumps, and in particular to a screw vacuum pump gap adjustment device and a screw vacuum pump. Background Art

[0002] In a screw vacuum pump, there is a certain gap between the paired screws and between the screw and the pump body. These gaps will cause gas reflux under the action of pressure difference, and gas reflux will significantly affect the key performance indicators of the vacuum pump, including pumping efficiency, pumping rate and ultimate pressure.

[0003] However, the high-speed rotation of the screw compresses the gas, causing the temperature to rise, which in turn causes thermal deformation of the rotor. This thermal deformation will reduce the gaps between the rotors and between the rotor and the pump chamber. In extreme cases, too small a gap may cause mechanical contact or jamming, which in turn affects the normal operation of the vacuum pump.

[0004] Therefore, reasonable control of the gap size can effectively solve the problem of thermal deformation, which is crucial to ensuring the performance and stability of the screw vacuum pump. Summary of the invention

[0005] The embodiments of the present application at least provide a screw vacuum pump gap adjustment device and a screw vacuum pump, which can solve the thermal deformation problem of the screw rotor through gap control and ensure the performance and stability of the screw vacuum pump.

[0006] In a first aspect, an embodiment of the present application provides a gap adjustment device for a screw vacuum pump, wherein the screw vacuum pump comprises a pump chamber and a screw rotor, wherein the pump chamber has a first end cover located at an air inlet side thereof and a second end cover located at an air outlet side thereof, wherein the screw rotor is rotatably disposed in the pump chamber, wherein the screw rotor comprises a rotor shaft and a rotor element disposed on the rotor shaft, wherein the device comprises a gap adjustment plate, a drive assembly, a detection assembly, and a controller;

[0007] The gap adjustment plate is movably arranged on a side of the second end cover facing the rotor element, and a gap is provided between the gap adjustment plate and an end surface of the rotor element;

[0008] The driving assembly is configured to drive the gap adjustment plate to reciprocate along the axial direction of the rotor element;

[0009] The detection component is configured to detect the working status information of the screw vacuum pump;

[0010] The controller is configured to control the driving assembly to operate according to the operating state information so that the gap between the gap adjustment plate and the end surface of the rotor element is maintained within a preset range.

[0011] In an optional embodiment, the inner wall of the second end cover is provided with a sink groove, and the gap adjustment plate is movably disposed in the sink groove.

[0012] In an optional embodiment, the gap adjustment plate is slidably fitted with the side wall of the sink.

[0013] In an optional embodiment, the drive assembly is located between the gap adjustment plate and the second end cover.

[0014] In an optional embodiment, the driving assembly includes a push rod, a turbine and a worm, one end of the push rod is vertically connected to the gap adjustment plate, and the other end of the push rod is threadedly connected to the inner hole of the turbine, and the transmission pair composed of the turbine and the worm is installed on the bottom wall of the trough, and the rotational motion of the worm is converted into reciprocating motion of the push rod through the turbine, and the push rod drives the gap adjustment plate to move.

[0015] In an optional embodiment, the detection component includes a pressure sensor, and the pressure sensor is used to detect the exhaust pressure of the screw vacuum pump, so that the controller controls the drive component to operate when the exhaust pressure reaches a preset value.

[0016] In an optional embodiment, the pressure sensor is disposed at the exhaust port of the second end cover.

[0017] In an optional embodiment, the detection component includes a temperature sensor, which is used to detect the exhaust end rotor temperature of the screw vacuum pump, so that the controller controls the drive component to operate when the exhaust end rotor temperature reaches a preset value.

[0018] In an optional embodiment, the temperature sensor is arranged at the shaft seal of the screw rotor.

[0019] In a second aspect, an embodiment of the present application further provides a screw vacuum pump, comprising the screw vacuum pump gap adjustment device described in any embodiment of the first aspect.

[0020] The above technical solution of the present application has the following beneficial technical effects:

[0021] The gap adjustment device of the screw vacuum pump in the embodiment of the present application includes a gap adjustment plate, a drive component, a detection component and a controller. The controller can control the drive component based on the detection information to make the gap adjustment plate reciprocate along the axial direction of the rotor element, thereby adjusting the gap size between the gap adjustment plate and the end face of the rotor element, and then solving the thermal deformation problem of the screw rotor through gap control to ensure the performance and stability of the screw vacuum pump.

[0022] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. The drawings herein are incorporated into the specification and constitute a part of the specification. These drawings illustrate embodiments consistent with the present application and are used together with the specification to illustrate the technical solutions of the present application. It should be understood that the following drawings only illustrate certain embodiments of the present application and should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can also be obtained based on these drawings without creative work.

[0024] Figure 1 A structural diagram of a screw vacuum pump provided in an embodiment of the present application is shown;

[0025] Figure 2 The figure shows an assembly diagram of the second end cover and the screw rotor provided in the embodiment of the present application;

[0026] Figure 3 The figure shows an assembly diagram of a drive assembly provided in an embodiment of the present application;

[0027] Figure 4 A schematic diagram of the assembly of the drive assembly provided in the embodiment of the present application from another perspective is shown;

[0028] Figure 5 A schematic diagram of assembling the ejector rod and the gap adjustment plate provided in an embodiment of the present application is shown;

[0029] Figure 6 The schematic diagram of the assembly of the turbine and the second end cover provided in the embodiment of the present application is shown;

[0030] Figure 7 A schematic diagram showing a gap adjustment plate provided in an embodiment of the present application before movement is shown;

[0031] Figure 8 A schematic diagram showing the gap adjustment plate provided in an embodiment of the present application after movement is shown;

[0032] In the figure: 1, pump chamber; 2, first end cover; 3, second end cover; 31, sink; 32, bearing; 33, shaft seal; 4, screw rotor; 41, rotor shaft; 42, rotor element; 100, gap adjustment plate; 200, drive assembly; 201, push rod; 202, turbine; 203, worm; 204, turbine bracket; 300, detection assembly; 301, pressure sensor; 302, temperature sensor; 400, controller. DETAILED DESCRIPTION

[0033] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0034] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0035] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0036] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0037] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0038] refer to Figure 1, the embodiment of the present application provides a screw vacuum pump, the screw vacuum pump includes a pump chamber 1 and a screw rotor 4, the pump chamber 1 has a first end cover 2 located on its air inlet side and a second end cover 3 located on its air outlet side, the screw rotor 4 is rotatably arranged in the pump chamber 1, and the screw rotor 4 includes a rotor shaft 41 and a rotor element 42 arranged on the rotor shaft 41. During use, the screw rotor 4 can rotate under the drive of an external motor. During the rotation of the screw rotor 4, the external gas enters the pump chamber 1 through the air inlet of the first end cover 2 and gradually moves toward the second end cover 3 along the axial direction. As the gas approaches the second end cover 3, the gas is gradually compressed to the required pressure level in the space between the screw teeth. When the gas is compressed to a sufficiently high pressure, the exhaust port of the second end cover 3 is opened, and the gas is discharged from the exhaust port to the outside of the pump. It should be noted that the temperature of the gas will rise during the compression process, which may cause thermal deformation of the screw rotor 4, resulting in a smaller gap between the rotor and the rotor, and between the rotor and the pump chamber 1, and even affecting the normal operation of the vacuum pump.

[0039] refer to Figures 1 to 6 The embodiment of the present application also provides a screw vacuum pump gap adjustment device, which can control the gap size between the second end cover 3 and the end face of the rotor element 42, thereby managing the thermal deformation problem of the screw rotor 4 through gap control to ensure the performance and stability of the screw vacuum pump.

[0040] Specifically, the adaptive end face clearance adjustment device includes a clearance adjustment plate 100, a drive assembly 200, a detection assembly 300 and a controller 400. The clearance adjustment plate 100 is movably arranged on the side of the second end cover 3 facing the rotor element 42, and there is a gap between the clearance adjustment plate 100 and the end face of the rotor element 42. The drive assembly 200 is configured to be able to drive the clearance adjustment plate 100 to reciprocate along the axial direction of the rotor element 42. The detection assembly 300 is configured to be able to detect the working state information of the screw vacuum pump (the information is used to reflect whether the screw rotor 4 is thermally deformed, such as the exhaust pressure and exhaust end rotor temperature of the screw vacuum pump). The controller 400 is configured to be able to control the operation of the drive assembly 200 according to the working state information (when the screw rotor 4 is thermally deformed) so that the clearance between the clearance adjustment plate 100 and the end face of the rotor element 42 is maintained within a preset range.

[0041] In the above scheme, the gap adjustment plate 100 is located between the second end cover 3 and the end face of the rotor element 42, and a gap for gas reflux can be formed between the gap adjustment plate 100 and the end face of the rotor element 42. In addition, since the gap adjustment plate 100 can move along the axial direction of the rotor element 42 under the action of the drive assembly 200, the gap size between the gap adjustment plate 100 and the end face of the rotor element 42 is adjustable. Therefore, when the rotor element 42 undergoes thermal deformation, resulting in a decrease in the gap between its end face and the gap adjustment plate 100, the gap adjustment plate 100 can be moved to keep the gap between the gap adjustment plate 100 and the end face of the rotor element 42 within a preset range, thereby ensuring that the vacuum pump can operate normally. In addition, the drive assembly 200 can be controlled by the controller 400 based on the detection information, so that the gap adjustment plate 100 can be automatically controlled, which is conducive to improving the performance, reliability and adaptability of the system, while reducing the need for manual intervention and resource consumption.

[0042] In addition, since the second end cover 3 is the area with the highest temperature during the gas compression process, the thermal expansion has the most significant effect on the gap. Therefore, setting the gap adjustment plate 100 on the second end cover 3 can directly deal with the gap change caused by thermal deformation and ensure stable operation of the system.

[0043] It should be noted that in the present application, the gap between the gap adjustment plate 100 and the end surface of the rotor element 42 is controlled within a range, and is not constant. When the gap is adjusted according to temperature or pressure, it is also based on the temperature or pressure reaching a certain range, rather than adjusting as soon as it rises. The specific temperature range or pressure range can be set according to specific parameters such as the operating parameters of the vacuum pump, the design value of the vacuum degree of the vacuum pump, the material of the vacuum pump rotor and stator, and is not specifically limited here.

[0044] Optionally, the gap adjustment plate 100, the drive assembly 200, the detection assembly 300 and the controller 400 are all arranged on the second end cover 3. This arrangement can realize the centralized arrangement of the gap adjustment plate 100, the drive assembly 200, the detection assembly 300 and the controller 400, which can reduce the complexity of pipes, cables and other connectors and reduce the possibility of system failure. Moreover, the second end cover 3 is usually designed as a structure that is easy to disassemble and access, which is convenient for technicians to operate. All key components are concentrated on the second end cover 3, which can reduce the area that maintenance personnel need to check and improve work efficiency.

[0045] For example, the gap adjustment plate 100, the drive assembly 200 and the detection assembly 300 are all arranged inside the second end cover 3, and the controller 400 is arranged outside the second end cover 3. Since the second end cover 3 is the area with the highest temperature during the gas compression process, the influence of thermal expansion on the gap is most significant. Therefore, the detection assembly 300 is arranged inside the second end cover 3, which can more accurately monitor the exhaust pressure, temperature and other parameters, and respond to changes quickly. The controller 400 is arranged outside the second end cover 3, so that the controller 400 works in a relatively stable environment, which can avoid performance degradation or damage caused by excessive temperature, and improve reliability and life.

[0046] Optionally, refer to Figures 1 to 4 The gap adjustment plate 100 is movably arranged in the sink 31 of the inner wall of the second end cover 3. In this way, the gap adjustment plate 100 can be installed by utilizing the space of the inner wall of the second end cover 3, reducing the dependence on external connectors (such as bolts, brackets, etc.), while avoiding additional external expansion, which is conducive to reducing the overall volume of the device. In addition, since the dependence on external connectors is reduced, the gap adjustment plate 100 is easy to disassemble and assemble without complicated tools or steps.

[0047] Optionally, the gap adjustment plate 100 is slidably matched with the side wall of the sink 31. In this way, the sink 31 can be used to guide the gap adjustment plate 100, so that the gap adjustment plate 100 moves more stably and reliably.

[0048] Optionally, a through hole is provided in the gap adjustment plate 100 , and the through hole is used for the rotor shaft 41 to pass through so as to be rotationally connected with the bearing 32 of the second end cover 3 .

[0049] Optionally, refer to Figure 1 A shaft seal 33 is provided between the gap adjustment plate 100 and the bearing 32 of the second end cover 3 and the rotor shaft 41 to achieve gas sealing.

[0050] Optionally, refer to Figure 4 The driving assembly 200 is located between the gap adjustment plate 100 and the second end cover 3. This arrangement can significantly shorten the transmission path, improve the response speed and control accuracy.

[0051] Optionally, refer to Figure 3 and Figure 4The driving assembly 200 includes a mandrel 201, a turbine 202 and a worm 203. One end of the mandrel 201 is vertically connected to the gap adjustment plate 100, and the other end of the mandrel 201 is threadedly connected to the inner hole of the turbine 202. The transmission pair composed of the turbine 202 and the worm 203 is installed on the bottom wall of the sink 31. The rotational movement of the worm 203 is converted into the reciprocating movement of the mandrel 201 through the turbine 202, and the mandrel 201 drives the gap adjustment plate 100 to move. In specific use, the worm 203 can rotate circumferentially under the action of the motor, and the worm 203 can drive the turbine 202 to rotate circumferentially when the worm 203 rotates circumferentially. When the turbine 202 rotates circumferentially, it can drive the mandrel 201 to reciprocate axially. When the mandrel 201 reciprocates axially, it can drive the gap adjustment plate 100 to approach or move away from the end face of the rotor element 42, so as to achieve the adjustable gap size between the gap adjustment plate 100 and the end face of the rotor element 42.

[0052] Optionally, refer to Figure 6 The turbine bracket 204 is disposed at one end of the turbine 202 facing the second end cover 3. The turbine bracket 204 is connected to the inner wall of the second end cover 3 and forms a plane rotation pair, which can make the turbine 202 rotate circumferentially on the plane of the inner wall of the second end cover 3. For example, the turbine bracket 204 can be a sleeve, which is sleeved outside the rotating shaft of the inner wall of the second end cover 3 and can rotate circumferentially relative to the rotating shaft, so that the turbine 202 can be rotatably disposed on the inner wall of the second end cover 3.

[0053] Optionally, the detection component 300 includes a pressure sensor 301, and the pressure sensor 301 is used to detect the exhaust pressure of the screw vacuum pump. The exhaust pressure of the screw vacuum pump can reflect whether the screw rotor 4 has undergone thermal deformation. Specifically, after the screw rotor 4 has undergone thermal deformation, the gap between the rotor element 42 and the pump chamber 1 is reduced, and the gas is further compressed. Therefore, it is possible to determine that the screw rotor 4 has undergone thermal deformation based on the change in gas pressure. In a specific setting, the pressure sensor 301 can be connected to the controller 400 with an electrical signal, and the pressure sensor 301 can send detection information to the controller 400, so that the controller 400 controls the drive component 200 to operate when the exhaust pressure reaches a preset value. When the drive component 200 is operating, the drive gap adjustment plate 100 moves along the axial direction of the rotor element 42 in a direction away from the end face of the rotor element 42, such as Figure 7 and Figure 8 shown.

[0054] Optionally, the pressure sensor 301 is disposed at the exhaust port of the second end cover 3. The exhaust port of the second end cover 3 is the final outlet of the gas compression process. By monitoring the exhaust pressure at the exhaust port of the second end cover 3, the gap change between the rotor and the pump chamber 1 can be predicted, and the gap size can be adjusted in time to prevent jamming or wear. In addition, since the pressure change at the exhaust port of the second end cover 3 is the most significant and stable, arranging the pressure sensor 301 there helps to improve the detection accuracy.

[0055] Optionally, the detection component 300 includes a temperature sensor 302, and the temperature sensor 302 is used to detect the exhaust end rotor temperature of the screw vacuum pump (i.e., the temperature of the screw rotor 4 close to the exhaust side). The exhaust end rotor temperature of the screw vacuum pump can reflect whether the screw rotor 4 has undergone thermal deformation. Specifically, after the screw rotor 4 has undergone thermal deformation, the gap between the rotor element 42 and the pump chamber 1 is reduced, and the gas is further compressed. Therefore, it is possible to determine whether the screw rotor 4 has undergone thermal deformation based on the change in the exhaust end rotor temperature. In a specific setting, the temperature sensor 302 can be connected to the controller 400 by an electrical signal, and the temperature sensor 302 can send detection information to the controller 400, so that the controller 400 controls the drive component 200 to operate when the exhaust end rotor temperature reaches a preset value. When the drive component 200 is operating, the drive gap adjustment plate 100 moves along the axial direction of the rotor element 42 in a direction away from the end face of the rotor element 42, such as Figure 7 and Figure 8 shown.

[0056] Optionally, the temperature sensor 302 is disposed at the shaft seal 33 of the screw rotor 4. The temperature at the shaft seal 33 can directly reflect the degree of thermal expansion of the rotor element 42. By monitoring the temperature of the shaft seal 33, the change in the gap between the rotor and the pump chamber 1 can be predicted, and the gap size can be adjusted in time to prevent jamming or wear. In addition, since the shaft seal 33 is usually designed as a structure that is easy to disassemble and inspect, arranging the temperature sensor 302 here can facilitate the installation and maintenance of the temperature sensor 302.

[0057] The gap adjustment device of the screw vacuum pump of the embodiment of the present application includes a gap adjustment plate 100, a drive assembly 200, a detection assembly 300 and a controller 400. The controller 400 can control the drive assembly 200 based on the detection information to make the gap adjustment plate 100 reciprocate along the axial direction of the rotor element 42, thereby adjusting the gap size between the gap adjustment plate 100 and the end face of the rotor element 42, and then solving the thermal deformation problem of the screw rotor 4 through gap control, thereby ensuring the performance and stability of the screw vacuum pump.

[0058] One or more embodiments of this specification are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this specification should be included in the scope of protection of this application.

[0059] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A screw vacuum pump clearance adjustment device, the screw vacuum pump comprising a pump chamber and a screw rotor, the pump chamber having a first end cover located at its air inlet side and a second end cover located at its air outlet side, the screw rotor being rotatably arranged in the pump chamber, the screw rotor comprising a rotor shaft and a rotor element arranged on the rotor shaft, characterized in that: The device comprises a gap adjustment plate, a driving assembly, a detection assembly and a controller; The gap adjustment plate is movably arranged on a side of the second end cover facing the rotor element, and a gap is provided between the gap adjustment plate and an end surface of the rotor element; The driving assembly is configured to drive the gap adjustment plate to reciprocate along the axial direction of the rotor element; The detection component is configured to detect the working status information of the screw vacuum pump; The controller is configured to control the driving assembly to operate according to the operating state information so that the gap between the gap adjustment plate and the end surface of the rotor element is maintained within a preset range.

2. The screw vacuum pump gap adjustment device according to claim 1, characterized in that: The inner wall of the second end cover is provided with a sinking groove, and the gap adjustment plate is movably arranged in the sinking groove.

3. The screw vacuum pump gap adjustment device according to claim 2, characterized in that: The gap adjustment plate is slidably matched with the side wall of the sink.

4. The screw vacuum pump gap adjustment device according to claim 2, characterized in that: The drive assembly is located between the gap adjustment plate and the second end cover.

5. The screw vacuum pump gap adjustment device according to claim 4, characterized in that: The driving assembly includes a push rod, a turbine and a worm. One end of the push rod is vertically connected to the gap adjustment plate, and the other end of the push rod is threadedly connected to the inner hole of the turbine. The transmission pair composed of the turbine and the worm is installed on the bottom wall of the trough. The rotational motion of the worm is converted into reciprocating motion of the push rod through the turbine, and the push rod drives the gap adjustment plate to move.

6. The screw vacuum pump gap adjustment device according to claim 1, characterized in that: The detection component includes a pressure sensor, and the pressure sensor is used to detect the exhaust pressure of the screw vacuum pump, so that the controller controls the drive component to work when the exhaust pressure reaches a preset value.

7. The screw vacuum pump gap adjustment device according to claim 6, characterized in that: The pressure sensor is arranged at the exhaust port of the second end cover.

8. The screw vacuum pump gap adjustment device according to claim 1, characterized in that: The detection component includes a temperature sensor, and the temperature sensor is used to detect the exhaust end rotor temperature of the screw vacuum pump, so that the controller controls the drive component to work when the exhaust end rotor temperature reaches a preset value.

9. The screw vacuum pump gap adjustment device according to claim 8, characterized in that: The temperature sensor is arranged at the shaft seal of the screw rotor.

10. A screw vacuum pump, characterized in that: The invention comprises a screw vacuum pump gap adjustment device as described in any one of claims 1 to 9.

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