Roots blower impeller contour molded line

Abstract

The utility model provides a Roots blower impeller contour molded line, and mainly relates to the field of Roots blowers. A Roots blower impeller contour molded line comprises an impeller, at least two blades are evenly arranged on the impeller in the circumferential direction, the roots of every two adjacent blades are connected through an inwards-concave section, the end of each blade is an outwards-convex section, a connecting section is arranged between the inwards-concave section and the outwards-convex section, the outer edge of each inwards-concave section is an arc line, and the outer edge of each outwards-convex section is an arc line. The outer edges of the connecting section and the outer convex section are a plurality of line segments which are connected with each other, and the connecting points of the adjacent line segments are located on a standard molded line. The machining method has the beneficial effects that the manufacturing cost can be greatly reduced, the tool abrasion is greatly reduced, and the machining size consistency is better.

Description

Technical Field

[0001] The invention mainly relates to the field of Roots blowers, in particular to an impeller profile line of a Roots blower. Background Art

[0002] The contour line of the impeller of the Roots blower occupies a very important position in the composition of the Roots blower. It is responsible for maintaining a very small gap between the impeller and the blade and between the impeller and the housing when the blower is running, and enables the blower to achieve the ideal air supply efficiency and the ideal inlet and outlet air pressure difference. The existing impeller contour line consists of: 1. The concave arc line close to the center of the impeller; 2. The convex arc line away from the center of the impeller; 3. The convex continuous curve connecting the concave arc and the convex arc. The impeller profile formed by the impeller profile of this structure can meet various basic requirements of the blower. However, it brings great difficulties to efficient and high-precision processing and manufacturing. The current common impeller surface processing method is to use a CNC bidirectional curve planer to plan out the impeller surface line by line along the impeller axis according to the impeller profile trajectory. It takes tens of thousands or even tens of thousands of tool round trips to complete the processing of the contour surface, and it often takes two such processes to finally complete the impeller surface processing process. The continuous processing time is usually more than ten, dozens or even hundreds of hours. For a long time, impeller profile processing has always been the longest and most difficult process to control in the manufacturing process of Roots blowers, which has directly resulted in high manufacturing costs and unstable and unsatisfactory manufacturing quality of Roots blowers. Summary of the invention

[0003] In order to solve the deficiencies of the prior art, the present invention provides a Roots blower impeller profile line, which greatly reduces the manufacturing cost, greatly reduces tool wear, and has better processing size consistency.

[0004] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0005] A Roots blower impeller contour profile, comprising an impeller, wherein at least two blades are evenly arranged in a circumference on the impeller, the roots of two adjacent blades are connected by a concave section, each blade end is a convex section, a connecting section is between the concave section and the convex section, the outer edge of the concave section is an arc, the outer edges of the connecting section and the convex section are a plurality of line segments connected to each other, and the connecting points of adjacent line segments are on a standard profile.

[0006] The impeller has 2-3 blades.

[0007] The lengths of the outer edge segments of the connecting segment and the outer convex segment are equal or similar.

[0008] The number of outer edge line segments of the connecting segment and the outer convex segment is between 50 and 2000.

[0009] The length of the connecting line segment between the connecting segment and the outer edge of the convex segment is 0.5-20 mm.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] The present invention provides a novel impeller profile of a Roots blower, which also plays the role of maintaining a stable gap between the impellers and between the impeller and the casing when the blower is running, and enables the blower to achieve an ideal air supply efficiency and maintain an ideal inlet and outlet wind pressure difference.

[0012] The new Roots blower impeller profile line brings great convenience to processing and manufacturing. By selecting the appropriate tool, using the method of CNC linkage, and adjusting the impeller angle and the position of the tool at the same time, each slender plane on the new impeller profile surface can be easily processed in the normal direction, and a small plane can be processed at a time, changing from the original line-by-line processing to plane-by-plane processing, which can improve the processing efficiency by 20 to 25 times. Not only does it greatly reduce the manufacturing cost, but also because the number of tool travels is greatly reduced after completing a profile processing, the tool wear will also be greatly reduced during the completion of a profile processing cycle. At the same time, from the beginning of processing to the completion of an impeller profile processing cycle, the processing size consistency will be better, and the impeller profile processing accuracy will be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attached Figure 1 It is a schematic diagram of the main viewing state structure of the present invention;

[0014] Attached Figure 2 It is a schematic diagram of the stereoscopic viewing angle structure of the present invention;

[0015] Attached Figure 3 It is a partial enlarged structural schematic diagram of part A of the present invention;

[0016] Attached Figure 4 It is a schematic diagram of the partially enlarged structure of part B of the present invention.

[0017] The numbers shown in the accompanying drawings are: 1, impeller; 11, concave section; 12, connecting section; 13, convex section. DETAILED DESCRIPTION

[0018] The present invention will be further described with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the application.

[0019] like Figure 1-4As shown, the impeller profile of a Roots blower of the present invention comprises an impeller 1, on which at least two blades are evenly arranged in a circumference. Taking a commonly used Roots blower as an example, the impeller usually has two or three blades. The roots of two adjacent blades are connected by an inner concave section 11. The inner concave section 11 is an arc surface, and a boring machine can be directly used to process the inner arc surface during processing, with high processing efficiency.

[0020] Each blade end is a convex section 13, which is an outward convex arc in the prior art. The concave section 11 and the convex section 13 are connected by a connecting section 12, which is a transition curve connecting the concave section 11 to the convex section 13 in the prior art. The connecting section 12 and the convex section 13 are continuous curved surfaces formed by reciprocating tens of thousands or even hundreds of thousands of times using a planer. In this embodiment, only the outer edge of the concave section 11 is designed as an arc, and the outer edges of the connecting section 12 and the convex section 13 are several line segments connected to each other. The lengths of the outer edge line segments of the connecting section 12 and the convex section 13 are equal or similar, and the connecting points of adjacent line segments are on the standard profile line, such as Figure 4 As shown, the dotted part is the standard profile, and the junction of two adjacent line segments just coincides with the standard profile. Specifically, the connecting segment 12 and the convex segment 13 are connected by a number of straight lines of equal or similar lengths, and each intersection point coincides with the continuous curve or convex arc line at the location (i.e., the standard profile that can ensure the operation of the impeller), so that the original convex continuous curve (convex segment 13) and convex arc line (connecting segment 12) become broken lines close to the original contour line. A number of slender planes are formed on the impeller surface corresponding to the contour profile, and each slender plane cuts the arc surface at the corresponding position and intersects in sequence. The edges and corners formed by the intersection coincide with the original arc surface at that location, forming a new contour profile.

[0021] More specifically, according to the size of the impeller, the number of outer edge line segments of the connecting section 12 and the convex section 13 is between 50 and 2000, so that the number of outer edge line segments of the impeller can be adjusted according to the different impeller size requirements to ensure its accuracy. Compared with the traditional profile line structure, the present invention can greatly save processing steps and improve the processing efficiency by 20 to 25 times. Not only does it greatly reduce the manufacturing cost, but also because the number of tool movements is greatly reduced after completing one profile processing, the tool wear will also be greatly reduced within the cycle of completing one profile processing, reducing the loss of the tool. At the same time, according to different accuracy requirements and different impeller sizes, the length of the outer edge connecting line segment of the connecting section 12 and the convex section 13 is 0.5-20mm, so as to adapt to the processing requirements of impellers of different sizes.

[0022] A method for processing the contour line of a Roots blower impeller is used to process the contour line of the Roots blower impeller designed by the present invention. The overall processing requires two devices, one of which is a boring machine, which is used to bore the arc surface of the concave section 11 of the impeller so that the arc surface can be quickly processed. The other device is a special milling machine with a servo rotation function on the operating table. The impeller is fixed on the operating table with servo linkage, and the angle of each surface to be processed is adjusted by servo drive. Then, the servo displacement of the milling cutter of the milling machine contacts the surface to be processed and the milling of the plane where the multiple line segments on the connecting section 12 and the convex section 13 are located is completed. Compared with the existing planer processing method, this processing method has higher equipment accuracy and simpler processing procedures. Only simple boring processing and milling surface processing are required to replace the existing planer processing of thousands of round trips, which can improve the processing efficiency by 20 to 25 times and greatly save the processing cost of the Roots blower impeller. At the same time, this method also reduces the loss of the tool, which also saves processing costs.

Claims

1. A Roots blower impeller profile, comprising an impeller (1), wherein at least two blades are evenly arranged on the impeller (1) in a circumferential manner, characterized in that: Two adjacent blade roots are connected by an inner concave section (11), each blade end is an outer convex section (13), a connecting section (12) is between the inner concave section (11) and the outer convex section (13), the outer edge of the inner concave section (11) is an arc, the outer edges of the connecting section (12) and the outer convex section (13) are a plurality of line segments connected to each other, and the connection points of adjacent line segments are on a standard profile line.

2. The impeller profile of a Roots blower according to claim 1, characterized in that: The impeller (1) has 2-3 blades.

3. The impeller profile of a Roots blower according to claim 1, characterized in that: The lengths of the outer edge segments of the connecting segment (12) and the outer convex segment (13) are equal or similar.

4. The impeller profile of a Roots blower according to claim 1, characterized in that: The number of outer edge line segments of the connecting section (12) and the outer convex section (13) is between 50 and 2000.

5. The impeller profile of a Roots blower according to claim 1, characterized in that: The length of the outer edge connecting line segment between the connecting segment (12) and the outer convex segment (13) is 0.5-20 mm.

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