CN108443157B - Double-cavity sliding vane vacuum pump cylinder body and molded line design method thereof - Google Patents
Double-cavity sliding vane vacuum pump cylinder body and molded line design method thereof Download PDFInfo
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- CN108443157B CN108443157B CN201810560564.9A CN201810560564A CN108443157B CN 108443157 B CN108443157 B CN 108443157B CN 201810560564 A CN201810560564 A CN 201810560564A CN 108443157 B CN108443157 B CN 108443157B
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- 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
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
-
- 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
- F04C18/30—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
- F04C18/34—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members
- F04C18/344—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member
-
- 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
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
-
- 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
- F04C2250/00—Geometry
- F04C2250/30—Geometry of the stator
- F04C2250/301—Geometry of the stator compression chamber profile defined by a mathematical expression or by parameters
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Geometry (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Computational Mathematics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Pure & Applied Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Rotary Pumps (AREA)
Abstract
The invention discloses a cylinder body of a double-cavity sliding vane vacuum pump and a molded line design method thereof, wherein a cylinder body molded line is formed by adopting a sine spiral line, a first suction section curve and a second suction section curve, a first discharge section curve and a second discharge section curve are respectively symmetrical around the center of an original point, the component curves are completely and smoothly connected and have continuous second derivatives, the central angle corresponding to the first suction section curve is alpha, the central angle corresponding to the first discharge section curve is beta, alpha < beta and alpha+beta=180 degrees; two identical asymmetrical working chambers are formed between the cylinder body and the rotor: the first working cavity and the second working cavity reduce the exhaust volume and effectively increase the internal volume ratio; the cylinder body of the dual-cavity sliding vane vacuum pump ensures that the top end of the sliding vane does not generate rigid impact and flexible impact in the sliding process of keeping contact with the inner wall of the cylinder body, and the internal volume ratio of the sliding vane vacuum pump can be increased by changing the size of the central angle corresponding to the curve, so that the sliding vane vacuum pump has larger ultimate vacuum degree.
Description
Technical Field
The invention relates to a sliding vane vacuum pump, in particular to a cylinder body suitable for a double-cavity sliding vane vacuum pump and a molded line design method thereof.
Background
The sliding vane vacuum pump is a positive displacement fluid machine, and when rotating, the top end of the sliding vane is kept in contact with the inner wall of the cylinder body by centrifugal force, the rotor drives the sliding vane to slide along the inner wall of the cylinder body, and a closed working cavity is formed among the upper end cover, the lower end cover, the sliding vane, the rotor and the cylinder body, so that the suction, compression and discharge of gas are realized. The device has the advantages of high pumping speed, small volume and capability of pumping out a certain amount of condensable gas, and is widely applied to industries such as machinery, electronics, chemical industry, automobiles and the like. Common sliding vane vacuum pumps include single-chamber, double-chamber and three-chamber sliding vane vacuum pumps, and the design of cylinder body molded lines is particularly important for obtaining better working performance. Related researches have proposed multiple function molded lines, trigonometric function molded lines, multi-section combined curves and the like, but each working cavity of the corresponding cylinder body is of a symmetrical structure, the exhaust volume is larger, the internal volume ratio is small, and the compression efficiency is low.
Disclosure of Invention
In order to increase the internal volume ratio of the sliding vane vacuum pump and enrich the types of molded lines of the cylinder body, the invention provides a double-cavity sliding vane vacuum pump cylinder body and a molded line design method thereof. The sine spiral line is adopted to construct a cylinder body molded line, the ratio of the central angles corresponding to the suction section curve and the discharge section curve is changed, and the purposes of forming two same asymmetric working cavities between the cylinder body and the rotor, reducing the exhaust volume and increasing the internal volume ratio are achieved. All curves on the cylinder body molded line meet the condition that the second derivative is continuous, and the top end of the sliding vane is ensured not to generate rigid impact and flexible impact in sliding which keeps contact with the inner wall of the cylinder body.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
the utility model provides a two-chamber gleitbretter vacuum pump cylinder body, the molded lines in the cylinder body 1 distributes according to clockwise and does in proper order: the first suction section curve AB, the first discharge section curve BC, the second suction section curve CD and the second discharge section curve DA form a completely smooth connection and the second derivative is continuous; the point A and the point C are the lowest points which can be reached by the sliding vane and are positioned on the radius R taking the origin O as the circle center and the radius as the bottom circle radius 3 Is a circle; the point B and the point D are the highest points which can be reached by the sliding vane and are positioned on the radius R with the origin O as the center of a circle and the radius R as the radius of a top circle 1 Is a circle; the central angle AOB corresponding to the first suction section curve AB is alpha, and the central angle BOC corresponding to the first discharge section curve BC is beta, alpha<Beta and alpha+beta=180°; the first suction segment curve AB and the second suction segment curve CD are centrosymmetric about the origin O,the first exhaust section curve BC and the second exhaust section curve DA are centrally symmetrical around an origin O; two identical asymmetrical working chambers are formed between the cylinder body (1) and the rotor (2): a first working chamber (101) and a second working chamber (102).
The equation of the first suction section curve AB of the double-cavity sliding vane vacuum pump cylinder body is as follows:
the equation for the first exhaust section curve BC is:
while the curvature of the first suction section curve AB satisfies k AB >0，
Wherein: and t is a parameter.
The molded line design method of the double-cavity sliding vane vacuum pump cylinder body comprises the following steps:
1) Taking the origin O as the center of a circle and respectively taking the radius as the radius R of the top circle 1 And bottom radius R 3 Is a circle;
2) Let the magnitude of the central angle +.AOB corresponding to the first suction section curve AB of the cylinder body be alpha, and the magnitude of the central angle +.BOC corresponding to the first discharge section curve BC be beta, alpha < beta and alpha+beta=180°;
3) A sine spiral line is adopted to smoothly connect the top circle and the bottom circle, and a curve equation is solved;
4) Checking whether the curvature of the first suction section curve AB is constantly greater than zero, if the curvature of the first suction section curve AB does not meet the condition, returning to the second step, increasing the size alpha of the central angle AOB, and reducing the size beta of the central angle BOC until the curvature of the first suction section curve AB meets the condition;
5) And simultaneously rotating the first suction section curve AB and the first discharge section curve BC clockwise around the original point O by 180 degrees to obtain a second suction section curve CD and a second discharge section curve DA, thereby forming a complete cylinder body molded line.
The beneficial effects of the invention are as follows:
(1) The asymmetric working cavity structure improves the internal volume ratio of the sliding vane vacuum pump, so that the vacuum pump has larger ultimate vacuum degree;
(2) The internal volume ratio of the sliding vane vacuum pump can be adjusted by changing the corresponding central angle of the curve;
(3) The cylinder body composition curve satisfies the continuous second derivative, and ensures that the top end of the sliding vane does not generate rigid impact and flexible impact in sliding which keeps contact with the inner wall of the cylinder body;
(4) Enriches the cylinder body type line type of the double-cavity sliding vane vacuum pump.
Drawings
FIG. 1 is a cylinder type diagram of a dual-chamber slide vacuum pump.
Fig. 2 is a cylinder pattern diagram corresponding to different central angles of the curves.
Fig. 3 is a diagram of an asymmetrical working chamber.
Fig. 4 is a diagram showing the end of the suction process of the working chamber and the start of the compression process.
Fig. 5 is a diagram showing the end of the working chamber compression process and the start of the exhaust process.
In the figure:
R 1 -top circle radius; r is R 3 -base circle radius; alpha-central angle AOB; beta-central angle BOC; 1-a cylinder; 101-a first working chamber; 102-a second working chamber; 2-a rotor; 3-air suction port; 4-an exhaust port; 5-a first slide; 6-a second sliding sheet; s is S in -maximum inspiratory volume; s is S out -maximum exhaust volume; omega-rotational angular velocity.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 1, the molded lines in the cylinder 1 are distributed in a clockwise direction in turn: a first suction section curve AB, a first discharge section curve BC, a second suction section curve CD and a second discharge section curve DA, which form a completely smooth connection and a second orderThe derivative is continuous; the point A and the point C are the lowest points which can be reached by the sliding vane and are positioned on the radius R taking the origin O as the circle center and the radius as the bottom circle radius 3 Is a circle; the point B and the point D are the highest points which can be reached by the sliding vane and are positioned on the radius R with the origin O as the center of a circle and the radius R as the radius of a top circle 1 Is a circle; the central angle AOB corresponding to the first suction section curve AB is alpha, and the central angle BOC corresponding to the first discharge section curve BC is beta, alpha<Beta and alpha+beta=180°; the first suction section curve AB and the second suction section curve CD are centrally symmetrical around an origin O, and the first discharge section curve BC and the second discharge section curve DA are centrally symmetrical around the origin O; the equation for the first suction segment curve AB is:
the equation for the first exhaust section curve BC is:
wherein: and t is a parameter.
As shown in fig. 2, the magnitude α of the central angle AOB and the magnitude α1 of the central angle α0boc can be adjusted under the above conditions, when the difference between the magnitude α of the central angle AOB and the magnitude β of the central angle BOC is too large, the curvature of the curve of the first suction section curve AB near the point a is smaller than zero, the curve has an inward convex section, causing the contact and the falling of the sliding vane with the inner wall of the cylinder body, and the sliding vane is severely worn with the cylinder body at the position, so the magnitude α of the central angle AOB and the magnitude β of the central angle BOC are reasonably valued, thereby ensuring the curvature k of the first suction section curve AB AB >0，
The larger the difference value between the magnitude alpha of the central angle AOB and the magnitude beta of the central angle BOC is, the steeper the first suction section curve AB is, the flatter the first discharge section curve BC is, and the larger the internal volume ratio of the sliding vane vacuum pump is; the smaller the difference, the flatter the first suction section curve AB, the steeper the first discharge section curve BC, the smaller the internal volume ratio of the vane-cell vacuum pump, and when α=β, as shown by the broken line in the figure, the first suction section curve AB and the first discharge section curve BC are symmetrical with respect to the longitudinal axis.
As shown in fig. 3, two identical asymmetrical working chambers are formed between the cylinder 1 and the rotor 2: neither the first working chamber 101 nor the second working chamber 102 is symmetrical about the longitudinal axis.
As shown in fig. 4, when the rotor 2 is at the current position, the first slide 5 is positioned at the tail end of the air suction port 3, the air suction process of the working chamber is ended, the compression process is started, and the maximum air suction volume S shown as a shaded part is formed among the cylinder 1, the rotor 2, the first slide 5 and the second slide 6 in 。
As shown in fig. 5, when the rotor 2 is rotated clockwise to the current position, the second vane 6 is positioned at the initial end of the exhaust port 4, the compression process of the working chamber is ended, the exhaust process is started, and the maximum exhaust volume S shown as a hatched portion is formed among the cylinder 1, the rotor 2, the first vane 5 and the second vane 6 out The method comprises the steps of carrying out a first treatment on the surface of the The broken line in the figure shows the common cylinder profile with symmetrical working cavities, and the maximum exhaust volume in the asymmetrical working cavities is obviously smaller than that of the symmetrical working cavities under the same exhaust port position, so the volume ratio S in the cylinder body of the proposed double-cavity sliding vane vacuum pump in /S out The internal volume ratio is improved by more than 25 percent.
While the foregoing description of the embodiments of the present invention has been presented in conjunction with the drawings, it should be understood that it is not intended to limit the scope of the invention, but rather, it is intended to cover all modifications or variations within the scope of the invention as defined by the claims of the present invention.
Claims (2)
1. A dual-chamber sliding vane vacuum pump cylinder is characterized in that: the molded lines in the cylinder body (1) are distributed in a clockwise direction in turn: the first suction section curve AB, the first discharge section curve BC, the second suction section curve CD and the second discharge section curve DA form a completely smooth connection and the second derivative is continuous; point A and Point CIs the lowest point that the sliding vane can reach and is positioned at the radius R taking the origin O as the center and the radius as the bottom circle radius 3 Is a circle; the point B and the point D are the highest points which can be reached by the sliding vane and are positioned on the radius R with the origin O as the center of a circle and the radius R as the radius of a top circle 1 Is a circle; the central angle AOB corresponding to the first suction section curve AB is alpha, and the central angle BOC corresponding to the first discharge section curve BC is beta, alpha<Beta and alpha+beta=180°; the first suction section curve AB and the second suction section curve CD are centrally symmetrical around an origin O, and the first discharge section curve BC and the second discharge section curve DA are centrally symmetrical around the origin O; two identical asymmetrical working chambers are formed between the cylinder body (1) and the rotor (2): a first working chamber (101) and a second working chamber (102);
the equation of the first suction section curve AB of the cylinder body of the double-cavity sliding vane vacuum pump is as follows:
the equation for the first exhaust section curve BC is:
while the curvature of the first suction section curve AB satisfies k AB >0，
Wherein: and t is a parameter.
2. A method for designing a molded line of a cylinder of a double-cavity sliding vane vacuum pump as claimed in claim 1, characterized by comprising the steps of: the method comprises the following steps:
1) Taking the origin O as the center of a circle and respectively taking the radius as the radius R of the top circle 1 And bottom radius R 3 Is a circle;
2) Let the magnitude of the central angle +.AOB corresponding to the first suction section curve AB of the cylinder body be alpha, and the magnitude of the central angle +.BOC corresponding to the first discharge section curve BC be beta, alpha < beta and alpha+beta=180°;
3) Adopting a sine spiral to smoothly connect a top circle and a bottom circle, and solving a curve equation;
4) Checking whether the curvature of the first suction section curve AB is constantly greater than zero, if the curvature of the first suction section curve AB does not meet the condition, returning to the second step, increasing the size alpha of the central angle AOB, and reducing the size beta of the central angle BOC until the curvature of the first suction section curve AB meets the condition;
5) And simultaneously rotating the first suction section curve AB and the first discharge section curve BC clockwise around the original point O by 180 degrees to obtain a second suction section curve CD and a second discharge section curve DA, thereby forming a complete cylinder body molded line.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810560564.9A CN108443157B (en) | 2018-05-25 | 2018-05-25 | Double-cavity sliding vane vacuum pump cylinder body and molded line design method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810560564.9A CN108443157B (en) | 2018-05-25 | 2018-05-25 | Double-cavity sliding vane vacuum pump cylinder body and molded line design method thereof |
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| CN108443157A CN108443157A (en) | 2018-08-24 |
| CN108443157B true CN108443157B (en) | 2023-10-20 |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2623912Y (en) * | 2003-04-03 | 2004-07-07 | 西安交通大学 | Spiralism type compressing apparatus for novel cylinder molded lines |
| CN2771522Y (en) * | 2005-03-24 | 2006-04-12 | 陆春晖 | Two-acting sliding-vane compressor cylindr inner cavity molded line |
| CN101975164A (en) * | 2010-10-25 | 2011-02-16 | 重庆大学 | Rotary vane compressor |
| CN102182682A (en) * | 2011-05-31 | 2011-09-14 | 重庆大学 | Rotary vane compressor |
| CN202545248U (en) * | 2011-12-06 | 2012-11-21 | 侯敏 | Double-cylinder rotary compressor |
| CN204436788U (en) * | 2015-01-21 | 2015-07-01 | 广东美芝制冷设备有限公司 | Rotary compressor |
| CN105782021A (en) * | 2016-04-01 | 2016-07-20 | 西安交通大学 | Sliding sheet type overpressure recovery equipment |
| CN208380864U (en) * | 2018-05-25 | 2019-01-15 | 中国石油大学(华东) | A kind of two-chamber sliding vane vacuum pump cylinder body |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8936451B2 (en) * | 2011-11-15 | 2015-01-20 | Gast Manufacturing, Inc., A Unit Of Idex Corporation | Rotary vane pumps with asymmetrical chamber cavities |
| US9708924B2 (en) * | 2013-01-18 | 2017-07-18 | Kuwait University | Combined pump and energy recovery turbine |
-
2018
- 2018-05-25 CN CN201810560564.9A patent/CN108443157B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2623912Y (en) * | 2003-04-03 | 2004-07-07 | 西安交通大学 | Spiralism type compressing apparatus for novel cylinder molded lines |
| CN2771522Y (en) * | 2005-03-24 | 2006-04-12 | 陆春晖 | Two-acting sliding-vane compressor cylindr inner cavity molded line |
| CN101975164A (en) * | 2010-10-25 | 2011-02-16 | 重庆大学 | Rotary vane compressor |
| CN102182682A (en) * | 2011-05-31 | 2011-09-14 | 重庆大学 | Rotary vane compressor |
| CN202545248U (en) * | 2011-12-06 | 2012-11-21 | 侯敏 | Double-cylinder rotary compressor |
| CN204436788U (en) * | 2015-01-21 | 2015-07-01 | 广东美芝制冷设备有限公司 | Rotary compressor |
| CN105782021A (en) * | 2016-04-01 | 2016-07-20 | 西安交通大学 | Sliding sheet type overpressure recovery equipment |
| CN208380864U (en) * | 2018-05-25 | 2019-01-15 | 中国石油大学(华东) | A kind of two-chamber sliding vane vacuum pump cylinder body |
Non-Patent Citations (2)
| Title |
|---|
| 双工作腔滑片压缩机结构分析;马国远,郁永章;压缩机技术(第05期);第3-8页 * |
| 旋叶式压缩机的气缸型线研究;郭蓓,赵远扬,李连生,束鹏程;西安交通大学学报(第03期);第256-259页 * |
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