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CN117052664A - Multistage Roots vacuum pump unit - Google Patents

Multistage Roots vacuum pump unit Download PDF

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Publication number
CN117052664A
CN117052664A CN202311017627.3A CN202311017627A CN117052664A CN 117052664 A CN117052664 A CN 117052664A CN 202311017627 A CN202311017627 A CN 202311017627A CN 117052664 A CN117052664 A CN 117052664A
Authority
CN
China
Prior art keywords
stage
rotor
roots
lobe
pump
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311017627.3A
Other languages
Chinese (zh)
Inventor
雷震霖
孔祥玲
王云
杨帆
李鹏明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sky Development Co ltd Chinese Academy Of Sciences
Zhongkeyi Nantong Semiconductor Equipment Co ltd
Original Assignee
Sky Development Co ltd Chinese Academy Of Sciences
Zhongkeyi Nantong Semiconductor Equipment Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sky Development Co ltd Chinese Academy Of Sciences, Zhongkeyi Nantong Semiconductor Equipment Co ltd filed Critical Sky Development Co ltd Chinese Academy Of Sciences
Priority to CN202311017627.3A priority Critical patent/CN117052664A/en
Publication of CN117052664A publication Critical patent/CN117052664A/en
Pending legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
    • F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/126—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with radially from the rotor body extending elements, not necessarily co-operating with corresponding recesses in the other rotor, e.g. lobes, Roots type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
    • F04C23/02—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C25/00—Adaptations of pumps for special use of pumps for elastic fluids
    • F04C25/02—Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2240/00—Components
    • F04C2240/20—Rotors

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)

Abstract

The invention discloses a multistage Roots vacuum pump unit, which comprises a pump shell and a motor component for driving the vacuum pump unit to work, wherein an upper pump cavity and a lower pump cavity are respectively arranged at the upper end and the lower end of the inside of the pump shell, a multi-lobe Roots rotor component is arranged in the upper pump cavity and the lower pump cavity of the pump shell, and the motor component is arranged at one end of the pump shell and used for driving the multi-lobe Roots rotor component to work. The invention has simple structure and reasonable design, arranges the rotor and the shaft into an integrated structure, saves the use of connecting pieces, can effectively improve the assembly efficiency and the precision, has the arrangement form of multi-blade seven-stage rotors, can reduce the volume of a vacuum pump, improves the air extraction efficiency and reduces the energy consumption, and has stable and reliable operation, and the hemispherical structure can effectively cope with the conditions of dust and the like in the process environment.

Description

Multistage Roots vacuum pump unit
Technical Field
The invention relates to the technical field of dry vacuum pumps, in particular to a multistage Roots vacuum pump unit.
Background
The multi-stage dry vacuum pump has an increasingly wide range of applications, including roots + claw, all roots and all claw. Among them, the all roots vacuum pump is increasingly used in the semiconductor industry due to its advantages of low energy consumption, high pumping speed, etc.
The prior art has the following defects:
the Roots rotor structure and its combination determine the critical vacuum performance such as pumping speed, limit, etc. The existing common combination form is a Roots+claw type or congruent leaf Roots type, and the combination form often has the problems of high energy consumption, unsmooth exhaust and the like. Therefore, a rotor shaft structure of a vacuum pump in a brand new combination form and a multi-stage Roots dry vacuum pump are required to be designed.
Disclosure of Invention
The invention aims to provide a multistage Roots vacuum pump unit, which aims to solve the problems in the background technology.
In order to achieve the above purpose, the present invention provides the following technical solutions: the utility model provides a multistage roots vacuum pump unit, includes pump case and is used for driving the motor assembly of vacuum pump unit work, the inside upper and lower end of pump case is provided with pump chamber and lower pump chamber respectively, the pump case is provided with lobe rotor subassembly in upper pump chamber and lower pump chamber inside, motor assembly sets up the one end at the pump case and is used for driving the work of lobe rotor subassembly.
As a further improvement of the present invention, the multi-lobe Roots rotor assembly includes:
the driving rotor shaft is arranged inside the lower pump cavity;
the driven rotor shaft is arranged in the upper pump cavity, bearings are arranged at two ends of the driving rotor shaft and the driven rotor shaft, and the bearings are arranged on the pump shell;
and the multi-blade Roots rotor is arranged on the driving rotor shaft and the driven rotor shaft.
As a further improvement of the present invention, the multi-lobe Roots rotor includes a three-stage two-lobe Roots rotor, a two-stage four-lobe Roots rotor, and a two-stage five-lobe Roots rotor.
As a further improvement of the invention, the driving rotor shaft and the driven rotor shaft are integrated with the multi-lobe roots rotor.
As a further improvement of the invention, the arc surfaces of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor are provided with hemispherical structures, and the hemispherical structures are arranged on She Fengxiao arcs of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor.
As a further development of the invention, the multi-lobe roots rotors on the driving rotor shaft and the driven rotor shaft are identical and conjugate to each other.
As a further improvement of the invention, the upper end face of the pump shell is provided with an air inlet at the upper end of the upper pump cavity, and the lower end face of the pump shell is provided with an air outlet at the upper end of the lower pump cavity.
As a further improvement of the invention, the upper pump cavity and the lower pump cavity have the same structure, relatively independent space structures are arranged in the upper pump cavity and the lower pump cavity, and air flow channels are arranged between the cavities of all stages.
As a further improvement of the invention, the outer circle radius of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor is sequentially reduced along with the increase of the number of lobes, and the thickness dimension is sequentially reduced along with the increase of the number of stages.
As a further improvement of the invention, the inner dimensions of each stage of the upper pump cavity and the lower pump cavity are matched with the dimensions of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor.
Compared with the prior art, the invention has the beneficial effects that:
the multi-lobe Roots rotor comprises three-stage two-lobe Roots rotors, two-stage four-lobe Roots rotors and two-stage five-lobe Roots rotors, the outer circle radius of the three-stage two-lobe Roots rotors, the two-stage four-lobe Roots rotors and the two-stage five-lobe Roots rotors is sequentially reduced along with the increase of the number of lobes, the thickness dimension is sequentially reduced along with the increase of the number of stages, and the number of connecting pieces is saved and the assembly efficiency is effectively improved through the integral processing of the rotor and the shaft;
the multi-lobe rotor on the driving rotor shaft and the multi-lobe rotor on the driven rotor shaft are the same and conjugate, the driving rotor shaft, the driven rotor shaft and the multi-lobe rotor are integrated, and the number of connecting pieces is saved and the assembly efficiency is effectively improved through the integrated processing of the rotors and the shafts;
according to the invention, the arc surfaces of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor are respectively provided with a hemispherical structure, and the hemispherical structures are respectively arranged on She Fengxiao arcs of the three-stage two-lobe Roots rotor, the two-stage four-lobe Roots rotor and the two-stage five-lobe Roots rotor, so that dust particles generated in the process can be removed, the method is suitable for use occasions with dust particles in the process, and the method has good comprehensive performance and advantages.
Drawings
FIG. 1 is a schematic diagram of the overall structure of the present invention;
FIG. 2 is a schematic view of the air inlet and air outlet of the present invention;
FIG. 3 is a schematic view of the installation of the multi-lobe Roots rotor of the present invention;
FIG. 4 is an enlarged schematic view of a three-stage two-lobe Roots rotor according to the present invention.
In the figure: 1. a pump housing; 101. an upper pump chamber; 102. a lower pump chamber; 103. an air inlet; 104. an air outlet; 2. a motor assembly; 3. a multi-lobe Roots rotor assembly; 31. a driving rotor shaft; 32. a driven rotor shaft; 33. a bearing; 34. a multi-lobe Roots rotor; 341. three-stage two-lobe Roots rotor; 342. two-stage four-lobe Roots rotor; 343. two-stage five-lobe Roots rotor.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
It will be understood that when an element is referred to as being "mounted," "connected," or "disposed" on another element, it can be directly on the other element or be indirectly on the other element. It is to be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have the orientation specific to the specification, be constructed and operated in the specific orientation, and thus should not be construed as limiting the present invention.
As a further refinement of the present invention, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature.
Examples
Referring to fig. 1-4, the present invention provides a technical solution: the utility model provides a multistage roots vacuum pump unit, includes pump case 1 and is used for driving the motor assembly 2 of vacuum pump unit work, and the inside upper and lower end of pump case 1 is provided with pump chamber 101 and lower pump chamber 102 respectively, and pump case 1 is provided with lobe rotor subassembly 3 in upper pump chamber 101 and lower pump chamber 102 inside, and motor assembly 2 sets up the one end at pump case 1 and is used for driving the work of lobe rotor subassembly 3.
The multi-lobe rotor assembly 3 comprises a driving rotor shaft 31, a driven rotor shaft 32 and a multi-lobe rotor 34, wherein the driving rotor shaft 31 is arranged in the lower pump cavity 102, the driven rotor shaft 32 is arranged in the upper pump cavity 101, bearings 33 are arranged at two ends of the driving rotor shaft 31 and the driven rotor shaft 32, the bearings 33 are arranged on the pump shell 1, and the multi-lobe rotor 34 is arranged on the driving rotor shaft 31 and the driven rotor shaft 32.
The multi-lobe Roots rotor 34 includes a three-stage two-lobe Roots rotor 341, a two-stage four-lobe Roots rotor 342, and a two-stage five-lobe Roots rotor 343.
The driving rotor shaft 31, the driven rotor shaft 32 and the multi-lobe Roots rotor 34 are integrated, the motor assembly 2 comprises a motor shell and a motor, the motor shell is arranged on one side of the pump shell 1, the motor is arranged in the motor shell and is connected with the driving rotor shaft 31, and the driving rotor shaft 31 and the driven rotor shaft 32 are connected through gear transmission.
The arc surfaces of the three-stage two-lobe Roots rotor 341, the two-stage four-lobe Roots rotor 342 and the two-stage five-lobe Roots rotor 343 are provided with hemispherical structures, and the hemispherical structures are arranged on the She Fengxiao arcs of the three-stage two-lobe Roots rotor 341, the two-stage four-lobe Roots rotor 342 and the two-stage five-lobe Roots rotor 343.
The multi-lobe roots rotors 34 on the driving rotor shaft 31 and the driven rotor shaft 32 are identical and conjugate to each other.
An air inlet 103 is formed in the upper end face of the pump shell 1 at the upper end of the upper pump cavity 101, and an air outlet 104 is formed in the lower end face of the pump shell 1 at the upper end of the lower pump cavity 102.
The upper pump cavity 101 and the lower pump cavity 102 have the same structure, relatively independent space structures are arranged in the upper pump cavity 101 and the lower pump cavity 102, and air flow channels are arranged between all levels of cavities.
The outer circle radius of the three-stage two-lobe Roots rotor 341, the two-stage four-lobe Roots rotor 342 and the two-stage five-lobe Roots rotor 343 is sequentially reduced along with the increase of the number of lobes, and the thickness dimension is sequentially reduced along with the increase of the number of stages.
The inner dimensions of each stage of the upper pump chamber 101 and the lower pump chamber 102 are matched with the dimensions of the three-stage two-lobe Roots rotor 341, the two-stage four-lobe Roots rotor 342 and the two-stage five-lobe Roots rotor 343.
In the invention, the driving rotor shaft 31, the driven rotor shaft 32 and the multi-lobe Roots rotor 34 are integrally processed, the strength of a pump shaft structure is improved, the number of connecting pieces is saved, the assembly efficiency is improved, a 7-stage Roots rotor structure is adopted on the rotor shaft, the multi-lobe Roots rotor 34 comprises three-stage two-lobe Roots rotors 341, two-stage four-lobe Roots rotors 342 and two-stage five-lobe Roots rotors 343, and in addition, the combination of different lobe numbers is adopted, so that the energy consumption can be reduced, the air extraction efficiency is improved, the rotor surface is designed into a hemispherical structure, the arc surface of each stage Roots rotor is provided with a hemispherical structure, and the hemispherical structure is arranged on She Fengxiao arcs of each stage of rotor. Dust particles inhaled in the running process can be effectively removed, and the process applicability is stronger.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (10)

1. The utility model provides a multistage roots vacuum pump unit, includes pump case (1) and is used for driving motor assembly (2) of vacuum pump unit work, its characterized in that: the novel multi-blade Roots rotor pump is characterized in that an upper pump cavity (101) and a lower pump cavity (102) are respectively arranged at the upper end and the lower end of the inside of the pump shell (1), the pump shell (1) is internally provided with a multi-blade Roots rotor assembly (3) in the upper pump cavity (101) and the lower pump cavity (102), and the motor assembly (2) is arranged at one end of the pump shell (1) and used for driving the multi-blade Roots rotor assembly (3) to work.
2. A multi-stage roots vacuum pump set according to claim 1, wherein: the multi-lobe Roots rotor assembly (3) comprises:
a driving rotor shaft (31), the driving rotor shaft (31) being arranged inside the lower pump chamber (102);
the driven rotor shaft (32), the driven rotor shaft (32) is arranged in the upper pump cavity (101), bearings (33) are arranged at two ends of the driving rotor shaft (31) and the driven rotor shaft (32), and the bearings (33) are arranged on the pump shell (1);
a multi-lobe rotor (34), the multi-lobe rotor (34) being disposed on a driving rotor shaft (31) and a driven rotor shaft (32).
3. A multi-stage roots vacuum pump set according to claim 2, wherein: the multi-lobe Roots rotor (34) comprises a three-stage two-lobe Roots rotor (341), a two-stage four-lobe Roots rotor (342) and a two-stage five-lobe Roots rotor (343).
4. A multi-stage roots vacuum pump set according to claim 2, wherein: the driving rotor shaft (31), the driven rotor shaft (32) and the multi-blade Roots rotor (34) are integrated.
5. A multi-stage roots vacuum pump set according to claim 3, wherein: the arc surfaces of the three-stage two-lobe Roots rotor (341), the two-stage four-lobe Roots rotor (342) and the two-stage five-lobe Roots rotor (343) are respectively provided with a hemispherical structure, and the hemispherical structures are respectively arranged on She Fengxiao arcs of the three-stage two-lobe Roots rotor (341), the two-stage four-lobe Roots rotor (342) and the two-stage five-lobe Roots rotor (343).
6. A multi-stage roots vacuum pump set according to claim 2, wherein: the multi-lobe Roots rotors (34) on the driving rotor shaft (31) and the driven rotor shaft (32) are identical and conjugate to each other.
7. A multi-stage roots vacuum pump set according to claim 1, wherein: an air inlet (103) is formed in the upper end face of the pump shell (1) at the upper end of the upper pump cavity (101), and an air outlet (104) is formed in the lower end face of the pump shell (1) at the upper end of the lower pump cavity (102).
8. A multi-stage roots vacuum pump set according to claim 1, wherein: the upper pump cavity (101) and the lower pump cavity (102) are identical in structure, relatively independent space structures are arranged in the upper pump cavity (101) and the lower pump cavity (102), and air flow channels are arranged between all levels of cavities.
9. A multi-stage roots vacuum pump set according to claim 3, wherein: the outer circle radius of the three-stage two-lobe Roots rotor (341), the two-stage four-lobe Roots rotor (342) and the two-stage five-lobe Roots rotor (343) is sequentially reduced along with the increase of the number of lobes, and the thickness dimension is sequentially reduced along with the increase of the number of stages.
10. A multi-stage roots vacuum pump set according to claim 3, wherein: the upper pump cavity (101) and the lower pump cavity (102) are respectively matched with the three-stage two-lobe Roots rotor (341), the two-stage four-lobe Roots rotor (342) and the two-stage five-lobe Roots rotor (343) in size.
CN202311017627.3A 2023-08-14 2023-08-14 Multistage Roots vacuum pump unit Pending CN117052664A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311017627.3A CN117052664A (en) 2023-08-14 2023-08-14 Multistage Roots vacuum pump unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311017627.3A CN117052664A (en) 2023-08-14 2023-08-14 Multistage Roots vacuum pump unit

Publications (1)

Publication Number Publication Date
CN117052664A true CN117052664A (en) 2023-11-14

Family

ID=88660214

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311017627.3A Pending CN117052664A (en) 2023-08-14 2023-08-14 Multistage Roots vacuum pump unit

Country Status (1)

Country Link
CN (1) CN117052664A (en)

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