Unlock instant, AI-driven research and patent intelligence for your innovation.

Screw vacuum pump and design method for rotor profile thereof

A technology of screw vacuum pump and rotor profile, which is applied to parts, pumps, and pump components of pumping devices for elastic fluids, can solve the problem of uneven distribution of spacing, achieve improved overall performance, and uniform distribution of gaps between rotors. The effect of reducing leakage

Pending Publication Date: 2020-11-13
中科九微科技有限公司
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect of the uneven distribution of the spacing between the two screws of the screw vacuum pump in the prior art, thereby providing a design method of the screw vacuum pump and its rotor profile

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Screw vacuum pump and design method for rotor profile thereof
  • Screw vacuum pump and design method for rotor profile thereof
  • Screw vacuum pump and design method for rotor profile thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] This embodiment provides a method for designing the rotor profile of a screw vacuum pump, such as figure 1 , figure 2 As shown, on the basis of the existing profile of the rotor end surface, the arc shape of the dedendum arc line 6 and the point meshing epicycloid 2 is kept unchanged, and the dedendum arc line 6 and the point meshing epicycloid 2 are The intersection point is determined as A 1 .

[0054] Then include the following steps:

[0055] The first step is to reduce the radius of the existing addendum arc line 3 to r 2 -δ 2 , the δ 2 is the arc clearance of the tip of the tooth determined according to the working conditions.

[0056] The second step is to determine the intersection of the new addendum arc line 3 and the point meshing epicycloid 2 as A` 2 .

[0057] The third step is to turn the intermediate curve formed by the existing short epicycloid 4 and hypocycloid 5 towards the direction of the addendum arc line 3 as a whole by δ 1 angle, the δ ...

Embodiment 2

[0062] This embodiment provides a screw vacuum pump, such as Figure 3-6 During the rotation and meshing process of the screws shown, the meshing with a gap can be realized between the two screws, which avoids the influence of machining errors and the thermal deformation effect of the rotor during operation.

[0063] The screw vacuum pump provided in this embodiment includes: two screws 1 with the same end profile and opposite rotation directions. The end profile of the screw 1 is designed using the method described in Example 1, and the end profile is connected sequentially. The point meshing epicycloid 2, the addendum arc line 3, the short epicycloid 4, the hypocycloid 5 and the dedendum arc line 6;

[0064] The radius of the dedendum arc is r 1 , the radius of the addendum arc is r 2 -δ 2 , the pitch radius r of the two screws 1 p for:

[0065] The equation of the short epicycloid 4 is:

[0066]

[0067] Among them, the variable χ satisfies the following relation...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a screw vacuum pump and a design method for a rotor profile thereof, and belongs to the technical field of positive displacement dual-screw rotary compressors. The screw vacuumpump comprises two screw rods which are the same in end face profile and are reverse in rotation direction; the end face profiles of the screw rods consist of point engaging epicycloids, addendum arcs, short amplitude epicycloids, hypocycloids and dedendum arcs which are connected in sequence; the radiuses of the dedendum arcs are r<1>; the radiuses of the addendum arcs are r<2>-delta<2>; and thepitch radiuses of the two screw rods are r, i.e., r= (r<1>+ r<2>) / 2. The screw rod vacuum pump provided by the invention has a novel rotor profile, and the rotor profile is enabled to generate ascrew rod rotor structure according to a required gap via reasonable curve adjustment on the basis of rotor engagement, so that reasonable gap design can be performed in a profile design stage, and the rotor gap is allocated more uniformly. Thus, the leakage among the screw rod vacuum rotors is reduced, and the overall performance of the vacuum pump is enhanced.

Description

technical field [0001] The invention relates to the technical field of volumetric twin-screw rotary compressors, in particular to a design method of a screw vacuum pump and its rotor profile. Background technique [0002] With the development of the pharmaceutical and semiconductor industries, more and more scenarios with low pollution and high vacuum requirements are emerging in industrial production. The screw vacuum pump is the main pump type of large and medium-sized dry pumps for obtaining dry, low-pollution high-vacuum environments and compressing clean gases. The screw vacuum pump is an air pumping device that uses a pair of screws to perform synchronous high-speed reverse rotation in the pump casing to generate suction and exhaust. The core components of the screw vacuum pump are two rotors that mesh with each other. According to the structure of the rotor, the selection of the rotor profile generally conforms to the meshing theorem, that is, the seamless meshing be...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): F04C29/00F04C18/16F04C25/02G06F30/17
CPCF04C18/082F04C29/00F04C18/16F04C25/02F04C2250/20
Inventor 李丹童何志龙王国梁
Owner 中科九微科技有限公司