CN213176033U - Vacuum pump assembly and vacuum pump - Google Patents
Vacuum pump assembly and vacuum pump Download PDFInfo
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- CN213176033U CN213176033U CN202021321357.7U CN202021321357U CN213176033U CN 213176033 U CN213176033 U CN 213176033U CN 202021321357 U CN202021321357 U CN 202021321357U CN 213176033 U CN213176033 U CN 213176033U
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- 238000007789 sealing Methods 0.000 claims description 14
- 229910000990 Ni alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 2
- 238000005086 pumping Methods 0.000 abstract description 8
- 238000000034 method Methods 0.000 abstract description 7
- 230000008569 process Effects 0.000 abstract description 4
- 230000000740 bleeding effect Effects 0.000 abstract 1
- 239000013598 vector Substances 0.000 description 11
- 238000003754 machining Methods 0.000 description 10
- 238000005266 casting Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000007689 inspection Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000004576 sand Substances 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 239000010687 lubricating oil Substances 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 238000013178 mathematical model Methods 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- 229910001141 Ductile iron Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000014509 gene expression Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- OFNHPGDEEMZPFG-UHFFFAOYSA-N phosphanylidynenickel Chemical compound [P].[Ni] OFNHPGDEEMZPFG-UHFFFAOYSA-N 0.000 description 2
- 238000013519 translation Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 239000004811 fluoropolymer Substances 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
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Abstract
The utility model discloses a vacuum pump assembly and vacuum pump. The vacuum pump assembly comprises a shaft (3), a rotor (2) and a stator (1), wherein the inner teeth of the rotor (2) are meshed with the outer gear of the shaft (3), a first air inlet (11), a first air outlet (12), a second air inlet (13) and a second air outlet (14) are formed in the bottom of the inner cavity of the stator (1), and the rotor (2) is not in contact with the side wall of the inner cavity of the stator (3). The utility model discloses a vacuum pump assembly simple structure, simple to operate, work efficiency is high, and the operation is stable, can provide faster pumping speed in the scope pressure of broad, and the start-up speed is fast, can realize not oily clear process of bleeding.
Description
Technical Field
The utility model relates to a vacuum pump subassembly, vacuum pump especially relate to a vacuum pump subassembly, vacuum pump with interior shaft gear drive rotor.
Background
The precision vacuum pump is a necessary vacuum source device in the semi-conductor industry, and is also an indispensable basic product which directly influences the performance and quality of vacuum complete equipment, the precision vacuum pump mainly drives the rapid development of the semi-conductor industry, the chemical industry and the thin film industry, particularly, the semi-conductor industry completely uses a dry vacuum pump to replace an oil-sealed mechanical pump, and the dry pump manufacture becomes a new economic growth point in the vacuum manufacturing field.
Dry vacuum pumps generally include roots, nus, screw and scroll types. Roots or nots pumps are commonly used in multi-stage vacuum pumps and comprise a plurality of stators, each stator being associated with a pair of rotors inside it, typically multi-stage positive displacement pumps, the directions of rotation of each pair of rotors being opposite to each other. Prior art 1: CN209604238U discloses a dry vacuum pump in each pumping chamber of which a shaft supports a respective rotor component, the rotor having a roots-type profile within each pumping chamber. The dry vacuum pump is generally manufactured by ductile cast iron in the prior art due to the requirements of structural strength and machinability, but the high-temperature corrosive gas used in the semiconductor industry causes the corrosion of the ductile cast iron, which affects the service life of the dry vacuum pump. This prior art 1 enhances the corrosion resistance of the dry vacuum pump by coating the shaft, the rotor, or the stator with a coating layer including high phosphorus nickel and nickel phosphorus and a fluoropolymer, but increases the production difficulty and the structural complexity of the dry vacuum pump because each pumping chamber thereof needs to be provided with two shafts and rotors having opposite rotation directions, and there is still a possibility of tile burning due to friction between the rotors and the stator, and in practical use thereof, there may still be a need for an additional lubricating liquid providing device for providing lubrication.
Currently, there is also a pump structure with a triangular rotor, prior art 2: CN109595152A discloses a triangular rotor pump, in which a rotor rotates in a cylinder and the cylinder is divided into 3 different working chambers by the rotor, each of which completes a different working cycle. Although each pumping chamber only needs to be provided with a shaft and a device, the complexity of the structure is reduced, the cylinder body is contacted with 3 vertexes of the rotor, friction still exists in the working chamber, and the outlet and the inlet of the working cycle are positioned on the side surface of the pumping chamber, so that the size of a pump body is large, and the installation of a vacuum pump is not facilitated.
Therefore, how to make the vacuum pump have a simpler structure, thereby improving the convenience of production, installation and maintenance, and improving the working efficiency and the operation stability of the vacuum pump is a problem to be solved in the field.
Disclosure of Invention
In order to solve the problem that exists among the prior art, the utility model discloses a vacuum pump assembly, its technical scheme as follows:
a vacuum pump assembly comprising a shaft, a rotor, a stator, the shaft having an external gear rotating about an axial axis of the shaft; said rotor having an approximately triangular outer profile and having a hollowed out portion with internal teeth therein, said internal teeth of said rotor intermesh with said external gear of said shaft, said shaft rotationally driving said rotor; the stator is provided with a side wall and a bottom, the side wall encloses an inner cavity with an approximate 8-shaped outline, the upper half part of the 8-shaped outline is a first area of the inner cavity, and the lower half part of the 8-shaped outline is a second area of the inner cavity; the rotor is arranged in the inner cavity and is attached to the bottom of the stator to rotate; the upper half part of the inner cavity is provided with a first air inlet and a first air outlet, the lower half part of the inner cavity is provided with a second air inlet and a second air outlet, and the first air inlet, the first air outlet, the second air inlet and the second air outlet are all arranged at the bottom of the stator; the rotor is not in contact with the side wall of the inner cavity of the stator, and the distance between the top point of the rotor and the side wall of the inner cavity is 0.1-1 mm.
Preferably: the shaft (3), the rotor (2) and the stator (1) are made of high-nickel alloy materials.
Preferably: the opening shapes of the first air inlet (11)/the second air inlet (13) are approximately triangular, and two adjacent sides of the triangle are respectively parallel to the side of the rotor (2) facing the first area/the second area and the side wall of the first area/the second area at the end moment of the first air suction stroke/the second air suction stroke.
Preferably: the opening shapes of the first air outlet (12)/the second air outlet (14) are approximately triangular, and two adjacent sides of the triangle are respectively parallel to the side edge of the rotor facing the first area/the second area and the side wall of the first area/the second area at the starting moment of the first exhaust stroke/the second exhaust stroke.
The utility model also discloses a vacuum pump, which comprises the vacuum pump component; the vacuum pump assembly is installed inside casing (4) of vacuum pump, keeping away from of stator (1) the one end of bottom of stator (1) is located the first top surface of casing (4), casing (4) are in first top surface is open type opening open-ended tip is seted up and is used for holding seal groove (5) of sealing washer, a sealing flange (6) fixed mounting be in first top surface to with seal groove (5) cooperation is used for sealing the opening.
Preferably: the sealing flange is characterized in that a plurality of first convex arms (7) with through holes are arranged on the outer wall of the first top surface of the shell (4), a plurality of second convex arms (8) with through holes are correspondingly arranged on the side surface of the sealing flange (6), and bolts are used for penetrating through the corresponding through holes in the first convex arms (7) and the second convex arms, so that the sealing flange (6) is fixed on the shell (4).
Has the advantages that: the utility model discloses a vacuum pump subassembly, vacuum pump simple structure, simple to operate, work efficiency is high, and the operation is stable, easy maintenance when meetting the problem has saved the required time of a large amount of dismouting pumps simultaneously when the maintenance. The utility model has simple and stable operation, can provide fast pumping speed within a range of pressure intensity by driving the shaft and the rotor to run in an internal gear transmission mode, has fast starting speed and can work immediately; the rotor and the inner cavity of the pump stator are not in contact, a gap of 0.1-1mm exists between the rotor and the inner cavity of the pump stator, the pump cavity is sealed by the gap, and the rotor can run at high speed without using lubricating oil because no friction exists in the cavity, so that the oil-free and clean air suction process can be realized.
Drawings
Fig. 1 is a schematic diagram of the vacuum pump assembly and the vacuum pump of the present invention.
Fig. 2 is a schematic view of the shaft and rotor engagement of the present invention.
Fig. 3 is a schematic diagram of the operation of the first air inlet for air suction.
Fig. 4 is a schematic diagram of the operation of exhausting air from the first air outlet.
Fig. 5 is a schematic diagram of the operation of the second air inlet for air suction.
FIG. 6 is a schematic diagram of the second air outlet for exhausting air.
Detailed Description
Fig. 1 shows a vacuum pump assembly comprising a shaft 3, a rotor 2, a stator 1, said shaft 3 having an external gear, said rotor having an approximately triangular outer profile and having a hollow-out portion with internal teeth therein, as shown in fig. 2, the internal teeth of the rotor 2 and the external gear of the shaft 3 are intermeshed at position a in the figure. The stator 1 has a side wall and a bottom which together enclose an inner cavity, the inner surface of the side wall having an approximately 8-shaped contour.
The upper half part of the 8-shaped contour is a first area of the inner cavity, and the lower half part of the 8-shaped contour is a second area of the inner cavity.
The outline geometric molded line design process of the rotor 2 and the stator 1 is as follows:
1. establishing a plane coordinate system of the molded lines of the rotor 2 and the stator 1;
2. determining the rotor 2 line type;
3. solving a conjugate section (stator) mathematical model by using coordinate transformation;
4. the mathematical model of the rotor 2 and the stator 1 can be obtained by the equation of the simultaneous conjugate section mathematical model.
The specific method comprises the following steps:
the design relation of the rotor and the stator meets the coordinate transformation principle which is as follows
Rg＝xgig+ygjg+zgkg；Rf＝xfif+yfjf+zfkf；
Wherein, R isgExpression for any vector in a moving coordinate system Sg, i.e. Rg＝(xg，yg，jg)，RfThe expression in the system of static coordinates Sf representing this vector, i.e. Rf＝(xf，yf，jf) Wherein x isg，yg，zg，xf，yf， zfAre respectively a vector RgAnd RfVector parameter of ig，jg，kg，if，jf，kfRespectively, are expressions of coordinate systems Sg and Sf. No matter which coordinate system is used for description, the vector will not change, so: rg＝Rf，
xgig+ygjg+zgkg＝xfif+yfjf+zfkf
Performing inner product operation on the left side and the right side of the above formula respectively at the vectors if, jf and kf to obtain:
xg(igif)+yg(jgif)+zg(kgif)＝xf(ifif)+yf(jfif)+zf(kfif)
xg(igjf)+yg(jgjf)+zg(kgjf)＝xf(ifjf)+yf(jfjf)+zf(kfjf) (1)
xg(igkf)+yg(jgkf)+zg(kgkf)＝xf(ifkf)+yf(jfkf)+zf(kfkf)
where if, jf, kf are three unit vectors perpendicular to each other, so
igif＝jfjf＝kfkf＝1
Ifjf＝ifkf＝kfif＝0
Substituting the above formula into formula (1) to obtain
xf＝xg(igif)+yg(jgif)+zg(kgif)
yf＝xg(igjf)+yg(jgjf)+zg(kgjf)
Zf＝xg(igkf)+yg(jgkf)+zg(kgkf)
The above formula is expressed as a matrix
The above formula can be written as:
Rf＝LfgRg
wherein
The elements of this matrix must satisfy the following six conditions:
three unit vector length condition
a11 2+a12 2+a13 2＝1
a21 2+a22 2+a23 2＝1
a31 2+a32 2+a33 2＝1
And three unit vector orthogonality condition
a11a21+a11a22+a13a23＝0
a11a31+a12a32+a13a33＝0
a21a31+d22a32+a23a33＝0
By changing the above formula to a homogeneous coordinate system, a 4x4 order matrix Mfg can be obtained as follows
If the two coordinate systems are not coincident in situ, the vector Rg in the moving coordinate system can be represented as Rf in the static coordinate system, and the relationship is:
Rf＝Rg+R0
wherein R is0The position vector of the origin of the static coordinate system is expressed as: [ x ] of0，y0，z0，1]By the same procedure, the formula can be changed to Rf＝MfgRgWherein M isfgComprises the following steps:
the above formula includes two actions of translation and rotation, and the sequence is translation first and then rotation.
According to the coordinate transformation principle, the relationship between the rotor and the stator can be determined.
The rotor 2 is arranged in the inner cavity and is attached to the bottom of the stator 1 to rotate under the driving of a shaft 3. As shown in fig. 3 and 4, a first air inlet 11 and a first air outlet 12 are disposed in the upper half of the inner cavity, i.e., the first region. As shown in fig. 5 and 6, a second air inlet 13 and a second air outlet 14 are disposed in a second half portion, i.e., a second area, of the inner cavity. The first air inlet 11, the first air outlet 12, the second air inlet 13 and the second air outlet 14 are all arranged at the bottom of the inner cavity of the stator 1. Because the air inlet and the air outlet are both arranged at the bottom of the inner cavity, the space occupied by the vacuum pump assembly in the radial direction of the shaft can be reduced, and the vacuum pump assembly can adapt to more working occasions.
The rotor 2 is not in contact with the side wall of the inner cavity of the stator 1, and the distance between the top point of the rotor 2 and the side wall of the inner cavity is 0.1-1 mm. The pump cavity is sealed by a gap, and the rotor can run at high speed without using lubricating oil due to no friction in the cavity, so that an oil-free and clean air suction process can be realized, an additional lubricating oil supply mechanism is not required, and the pumping medium is not polluted.
In the vacuum pump assembly, the shaft 3, the rotor 2 and the stator 1 are made of high-nickel alloy materials.
Referring to fig. 3 and 5, the opening shape of the first air inlet 11/the second air inlet 13 of the vacuum pump assembly is approximately triangular, and two adjacent sides of the triangle are parallel to the side of the rotor facing the first area/the second area and the side wall of the first area/the second area at the end of the first air suction stroke and the second air suction stroke respectively.
Referring to fig. 4 and 6, the opening shape of the first air outlet 12/the second air outlet 14 of the vacuum pump assembly is approximately triangular, and two adjacent sides of the triangle are parallel to the side of the rotor facing the first area/the second area and the side wall of the first area/the second area at the beginning of the first exhaust stroke and the second exhaust stroke respectively.
The utility model discloses an air inlet, gas outlet shape can increase and breathe in/the displacement, improve the work efficiency who breathes in and exhaust stroke.
The utility model discloses a vacuum pump subassembly's concrete working process does:
the shaft rotates clockwise to drive the rotor to rotate clockwise correspondingly, as shown in fig. 3, the upper half part of the inner cavity forms negative pressure through the rotation of the rotor, so that the vacuum pump assembly performs air suction on a working environment connected with the vacuum pump assembly through the first air inlet 11 of the first area of the upper half part.
When the rotor is operated to close the first air inlet 11 in the first area of the upper half by using its own structural features, air is stopped to enter the next working state, i.e. the air exhaust state, and the first air exhaust port 12 is connected to the atmosphere to exhaust air out of the pump body, as shown in fig. 4.
The rotor continues to run and its structural features cause it to enter the second inlet position in the second region of the lower half of the cavity, opening the second inlet 13 and drawing gas into the cavity from the working environment to which it is connected, as shown in figure 5.
The rotor operates to close the second inlet port in the second region of the lower half of the internal chamber and then opens the second outlet port 14 in the second region of the lower half of the internal chamber and the compressed gas exits the pump body, as shown in figure 6.
Thus, the rotor 2 is driven by the rotation of the shaft 3 to continuously perform air suction and exhaust work, and the air suction and exhaust work is performed twice every time the rotor rotates one circle.
The specific production method of the vacuum pump assembly comprises the following steps:
1. casting: obtaining blanks of the shaft 3, the rotor 2 and the stator 1 by casting, firstly making a sand cavity and a sand core by using a sand mould, selecting the position of a sprue gate, controlling the temperature and the casting speed of cast molten iron, and keeping the machining allowance of a cast blank machining surface to be 4-5 mm; performing aging stress relief treatment after the blank is formed, performing defect inspection on the casting, such as shrinkage porosity, air holes, sand holes, slag inclusion, cracks and corrosion repair, and performing the next step after the inspection is qualified;
2. rough machining: machining the machined surface of the component by rough machining until the machining allowance is 2 mm;
3. and (3) a checking step: carrying out 3D coordinate inspection on the rough machined part after finishing roughing, carrying out internal inspection by using an endoscope, and carrying out internal sand eye and casting defect inspection by using ultrasonic flaw detection;
4. semi-processing: semi-finishing the machined surface of the casting until the machining allowance is 0.2 mm;
5. and (3) finishing: the method comprises the following steps of performing finish machining on a part in a grinding mode, controlling circular runout of a main shaft to be 0.012mm in the machining process, controlling surface finish to reach 0.8, ensuring verticality of a plurality of units on the main shaft and the main shaft to be 0.02, after finishing machining, performing precision detection on the main shaft by adopting three coordinates, wherein the size, form and position tolerance and roughness meet requirements, a runout detection value needs to be kept within 0.012mm, and the surface finish reaches 1.6 Ra;
6. the shaft 3 is fixedly connected with the external gear by a key and a key groove;
7. the rotor 2 is fixedly connected with the inner gear, and can be in a key-key groove connection mode;
8. the stator 1 is fixed on an operation table, and the installed rotor and the shaft are respectively installed in corresponding positions in a stator cavity in a hoisting mode.
The above-mentioned embodiments are preferred examples of the present invention, and should not be construed as limiting the present invention, and any modifications, equivalent replacements, improvements, etc. within the principle scope of the present embodiment should be included in the protection scope of the present invention.
Claims (6)
1. A vacuum pump assembly comprising a shaft (3), a rotor (2), a stator (1), characterized in that:
said shaft (3) having an external gear, rotating about the axial axis of said shaft (3);
the rotor (2) has an approximately triangular outer contour and has a cutout with internal teeth inside, the internal teeth of the rotor (2) intermesh with the external teeth of the shaft (3), the shaft (3) rotationally drives the rotor (2);
the stator (1) is provided with a side wall and a bottom, the side wall encloses an inner cavity with an approximate 8-shaped outline, the upper half part of the 8-shaped outline is a first area of the inner cavity, and the lower half part of the 8-shaped outline is a second area of the inner cavity;
the rotor (2) is arranged in the inner cavity and is attached to the bottom of the stator (1) to rotate;
the upper half part of the inner cavity is provided with a first air inlet (11) and a first air outlet (12), the lower half part of the inner cavity is provided with a second air inlet (13) and a second air outlet (14), and the first air inlet (11), the first air outlet (12), the second air inlet (13) and the second air outlet (14) are all arranged at the bottom of the stator (1);
the rotor (2) is not in contact with the side wall of the inner cavity of the stator (1), and the distance between the top point of the rotor (2) and the side wall of the inner cavity is 0.1-1 mm.
2. A vacuum pump assembly as claimed in claim 1, wherein: the shaft (3), the rotor (2) and the stator (1) are made of high-nickel alloy materials.
3. A vacuum pump assembly as claimed in claim 1, wherein: the opening shapes of the first air inlet (11)/the second air inlet (13) are approximately triangular, and two adjacent sides of the triangle are respectively parallel to the side of the rotor (2) facing the first area/the second area and the side wall of the first area/the second area at the end moment of the first air suction stroke/the second air suction stroke.
4. A vacuum pump assembly as claimed in claim 1, wherein: the opening shapes of the first air outlet (12)/the second air outlet (14) are approximately triangular, and two adjacent sides of the triangle are respectively parallel to the side edge of the rotor facing the first area/the second area and the side wall of the first area/the second area at the starting moment of the first exhaust stroke/the second exhaust stroke.
5. A vacuum pump, characterized by: the vacuum pump assembly comprises the vacuum pump assembly as claimed in any one of claims 1 to 4, the vacuum pump assembly is installed inside a casing (4) of the vacuum pump, one end of the side wall of the stator (1), which is far away from the bottom of the stator (1), is located on a first top surface of the casing (4), the casing (4) is an open opening on the first top surface, a sealing groove (5) for accommodating a sealing ring is formed at the end of the opening, and a sealing flange (6) is fixedly installed on the first top surface and is matched with the sealing groove (5) for sealing the opening.
6. A vacuum pump according to claim 5, wherein: the sealing flange is characterized in that a plurality of first convex arms (7) with through holes are arranged on the outer wall of the first top surface of the shell (4), a plurality of second convex arms (8) with through holes are correspondingly arranged on the side surface of the sealing flange (6), and bolts are used for penetrating through the corresponding through holes in the first convex arms (7) and the second convex arms, so that the sealing flange (6) is fixed on the shell (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021321357.7U CN213176033U (en) | 2020-07-08 | 2020-07-08 | Vacuum pump assembly and vacuum pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021321357.7U CN213176033U (en) | 2020-07-08 | 2020-07-08 | Vacuum pump assembly and vacuum pump |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213176033U true CN213176033U (en) | 2021-05-11 |
Family
ID=75791753
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021321357.7U Active CN213176033U (en) | 2020-07-08 | 2020-07-08 | Vacuum pump assembly and vacuum pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213176033U (en) |
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2020
- 2020-07-08 CN CN202021321357.7U patent/CN213176033U/en active Active
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