阅读说明：本技术 一种小尺寸叶轮及其五轴铣削加工方法 (Small-size impeller and five-axis milling method thereof ) 是由 刘永峰 陈立景 张庆伟 于 2020-04-30 设计创作，主要内容包括：本发明涉及一种小尺寸叶轮及其五轴铣削加工方法,叶轮包括主轴、设置在主轴顶部的齿轮、套设在主轴外部的套筒以及多个沿周向均匀布设在套筒侧面的叶片,相邻两叶片之间设有加强筋,主轴、齿轮及套筒同轴设置,主轴、齿轮、套筒、叶片及加强筋一体成型；利用五轴数控机床加工叶轮,分为毛坯预处理、建模、规划刀路、粗加工、半精加工、精加工等步骤。与现有技术相比,本发明能实现叶轮局部的高精度铣削加工,可适用于各种不同参数的叶轮加工,具有加工效率高、精度高、成品质量好等特点。(The invention relates to a small-size impeller and a five-axis milling method thereof, wherein the impeller comprises a main shaft, a gear arranged at the top of the main shaft, a sleeve sleeved outside the main shaft and a plurality of blades uniformly distributed on the side surface of the sleeve along the circumferential direction, reinforcing ribs are arranged between every two adjacent blades, the main shaft, the gear and the sleeve are coaxially arranged, and the main shaft, the gear, the sleeve, the blades and the reinforcing ribs are integrally formed; the impeller is machined by a five-axis numerical control machine tool, and the machining method comprises the steps of blank pretreatment, modeling, tool path planning, rough machining, semi-finish machining, finish machining and the like. Compared with the prior art, the invention can realize the high-precision milling of the local part of the impeller, is suitable for the processing of impellers with various parameters, and has the characteristics of high processing efficiency, high precision, good finished product quality and the like.)

1. The utility model provides a small-size impeller, its characterized in that, this impeller includes main shaft (1), set up gear (2) at main shaft (1) top, cover and establish sleeve (3) outside main shaft (1) and a plurality of evenly lay blade (4) in sleeve (3) side along circumference, be equipped with strengthening rib (5) between two adjacent blade (4), main shaft (1), gear (2) and sleeve (3) coaxial setting, main shaft (1), gear (2), sleeve (3), blade (4) and strengthening rib (5) integrated into one piece.

2. The small-sized impeller as claimed in claim 1, wherein the main shaft (1) is provided with a main shaft through hole (6) at the center thereof along the axial direction.

3. A small size impeller in accordance with claim 1, characterized in that the outer diameter of said gear wheel (2) is the same as the outer diameter of the main shaft (1).

4. The small-size impeller as claimed in claim 3, wherein a plurality of tooth grooves (7) are uniformly arranged on the outer side surface of the top of the main shaft (1) along the circumferential direction.

5. A small-sized impeller according to claim 4, characterized in that the thickness of the reinforcing ribs (5) is smaller than the height of the blades (4).

6. A small size impeller according to claim 5, characterized in that the bottom surface of the reinforcing rib (5) is flush with the bottom surface of the blade (4), and the top surface of the reinforcing rib (5) and two adjacent blades (4) define a groove (8).

7. A small size impeller in accordance with claim 6, characterized in that the inner end of the reinforcing rib (5) is connected to the sleeve (3) and the outer end is located between two adjacent vanes (4), and the length between the inner end and the outer end of the reinforcing rib (5) is 1/5-1/3 of the length of the vane (4).

8. A five-axis milling machining method for a small-sized impeller according to claim 6 or 7, characterized by comprising the steps of:

1) processing the blank into a convex round bar according to the shape and size parameters of the impeller to be processed;

2) modeling an impeller to obtain an impeller model;

3) roughly machining the blade (4) in a cavity milling mode;

4) performing semi-finishing on the reinforcing ribs (5) in a cavity milling mode;

5) performing semi-finishing on the blade (4) in a variable profile milling mode;

6) adopting a variable profile milling mode to finish the blade (4);

7) the outer end face of the reinforcing rib (5) is subjected to finish machining in a zone profile milling mode;

8) performing semi-finishing on the side surface of the groove (8) by adopting a deep processing five-axis milling mode;

9) performing semi-finishing on the bottom surface of the groove (8) in a variable profile milling mode;

10) performing finish machining on the side surface of the groove (8) in a deep machining five-axis milling mode;

11) finish machining is carried out on the bottom surface of the groove (8) in a variable profile milling mode;

12) roughly machining a tooth groove (7) of the gear (2) in a cavity milling mode;

13) and (3) performing finish machining on the tooth bottom surface of the gear (2) by adopting a plane profile milling mode, and performing finish machining on the tooth groove (7) of the gear (2) by adopting a depth profile machining mode.

9. The five-axis milling machining method for the small-sized impeller according to claim 8,

in the step 4), a milling cutter with the diameter of 4mm and the lower radius of 0.5 is adopted;

in the step 5), a milling cutter with the diameter of 3mm and the lower radius of 1.5mm is adopted;

in the step 6), a milling cutter with the diameter of 3mm and the lower radius of 1.5mm is adopted;

in the step 7), a milling cutter with the diameter of 3mm and the lower radius of 1.5 is adopted;

in the step 8), a milling cutter with the diameter of 2mm and the lower radius of 1mm is adopted;

in the step 9), a milling cutter with the diameter of 2mm and the lower radius of 1mm is adopted;

in the step 10), a milling cutter with the diameter of 1mm and the lower radius of 0.5mm is adopted;

in the step 11), a milling cutter with the diameter of 1mm and the lower radius of 0.5mm is adopted.

10. The five-axis milling machining method for the small-sized impeller according to claim 8,

in the step 3), the machining allowance of rough machining is 0.5 mm;

in the step 4), the machining allowance of the semi-finishing is 0.2 mm;

in the step 5), the machining allowance of the semi-finishing is 0.2 mm;

in the step 6), the machining allowance of finish machining is 0 mm;

in the step 7), the machining allowance of finish machining is 0 mm;

in the step 8), the machining allowance of the semi-finishing is 0.1 mm;

in the step 9), the machining allowance of the semi-finishing is 0.1 mm;

in the step 10), the machining allowance of finish machining is 0 mm;

in the step 11), the machining allowance of finish machining is 0 mm;

in the step 12), the machining allowance of rough machining is 0.1 mm;

in step 13), the finishing allowance is 0 mm.

Technical Field

The invention belongs to the technical field of impeller machining, and relates to a small-size impeller and a five-axis milling method thereof.

Background

With the continuous pursuit of high power, high output and high reliability, impulse turbines are continuously developed and innovated, and the part structures and the processing methods thereof are continuously changed. From rivet welding to integral casting and forging, and from pure manual grinding to numerical control machining, in the future, the impulse turbine is developed towards a direction of high water head and large capacity while the working efficiency is improved, but the machining method of the curved surface of the blade meets some bottlenecks in the perfecting process.

At present, the application of small-size impeller is more and more common, and how to design the structure of small-size impeller to satisfy the demand of practical application occasion is the problem that needs to be solved. In addition, the small-size impeller is often complex in structure and poor in openness, so that the machining process is complex and the manufacturing is very difficult.

Aiming at the structural characteristics and technical requirements of small-size impellers, four manufacturing methods are mainly adopted for the impellers at home and abroad at present: the method comprises the steps of block casting relief grinding, welding processing, riveting processing and integral numerical control processing. Although the integral numerical control machining has the greatest machining difficulty, the product quality is most easily guaranteed, and material defects possibly formed by block casting and relief grinding, stress and welding defects caused in welding machining and structural defects caused by riveting machining are avoided.

In the numerical control machining process of domestic small-size impeller products, due to the fact that no special equipment is available, three-axis equipment is generally adopted for machining. But limited to equipment considerations, few enterprises have processing capabilities. The method for machining the impact impeller by the five-axis equipment is very necessary to be developed by combining the current situation that the five-axis equipment is more in China.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, provide a small-size impeller and a five-axis milling method thereof, and solve the problems of high processing cost, low efficiency and poor gear quality in impeller processing in the prior art.

The purpose of the invention can be realized by the following technical scheme:

the utility model provides a small-size impeller, this impeller includes the main shaft, set up at the gear at main shaft top, the cover establish the outside sleeve of main shaft and a plurality of evenly lay the blade in the sleeve side along circumference, be equipped with the strengthening rib between two adjacent blades, main shaft, gear and the coaxial setting of sleeve, main shaft, gear, sleeve, blade and strengthening rib integrated into one piece. When the impeller is used, the impeller is sleeved on an impeller mounting shaft in the water turbine through the main shaft, and the motor drives the gear on the impeller to rotate through the intermediate gear, so that the impeller is driven to rotate. The reinforcing ribs are used for increasing the strength of the blade. All parts of the impeller are formed by milling in an integrated forming mode.

Furthermore, a main shaft through hole is formed in the center of the main shaft along the axial direction. The main shaft through hole is matched with an impeller mounting shaft in the water turbine.

Further, the outer diameter of the gear is the same as that of the main shaft.

Furthermore, a plurality of tooth grooves are uniformly formed in the outer side face of the top of the spindle along the circumferential direction to form a gear. The top end of the main shaft is directly processed into the gear, so that the problems of complex structure and welding defects caused by using another gear and fixing the other gear on the top end of the main shaft in a welding mode are avoided.

Further, the thickness of the reinforcing rib is smaller than the height of the blade.

Furthermore, the bottom surfaces of the reinforcing ribs are flush with the bottom surfaces of the blades, and a groove is formed between the top surface of each reinforcing rib and each two adjacent blades.

Further, the inner end of each reinforcing rib is connected with the sleeve, the outer end of each reinforcing rib is located between two adjacent blades, and the length between the inner end and the outer end of each reinforcing rib is 1/5-1/3 of the length of each blade.

A five-axis milling method for a small-size impeller comprises the following steps:

1) processing the blank into a convex round bar according to the shape and size parameters of the impeller to be processed;

2) modeling an impeller to obtain an impeller model;

3) roughly machining the blade in a cavity milling mode;

4) performing semi-finishing on the reinforcing ribs in a cavity milling mode;

5) performing semi-finishing on the blade by adopting a variable profile milling mode;

6) adopting a variable profile milling mode to finish the blade;

7) performing finish machining on the outer end face of the reinforcing rib in a zone profile milling mode;

8) performing semi-finishing on the side surface of the groove by adopting a deep processing five-axis milling mode;

9) performing semi-finishing on the bottom surface of the groove in a variable profile milling mode;

10) performing finish machining on the side surface of the groove by adopting a deep machining five-axis milling mode;

11) performing finish machining on the bottom surface of the groove in a variable profile milling mode;

12) roughly machining a gear tooth groove by adopting a cavity milling mode;

13) and performing finish machining on the bottom surface of the gear by adopting a plane profile milling mode, and performing finish machining on the tooth groove of the gear by adopting a depth profile machining mode.

Further, in the step 4), a milling cutter with the diameter of 4mm and the lower radius of 0.5 is adopted;

in the step 5), a milling cutter with the diameter of 3mm and the lower radius of 1.5mm is adopted;

in the step 6), a milling cutter with the diameter of 3mm and the lower radius of 1.5mm is adopted;

in the step 7), a milling cutter with the diameter of 3mm and the lower radius of 1.5 is adopted;

in the step 8), a milling cutter with the diameter of 2mm and the lower radius of 1mm is adopted;

in the step 9), a milling cutter with the diameter of 2mm and the lower radius of 1mm is adopted;

in the step 10), a milling cutter with the diameter of 1mm and the lower radius of 0.5mm is adopted;

in the step 11), a milling cutter with the diameter of 1mm and the lower radius of 0.5mm is adopted.

Further, in the step 3), the machining allowance of rough machining is 0.5 mm;

in the step 4), the machining allowance of the semi-finishing is 0.2 mm;

in the step 5), the machining allowance of the semi-finishing is 0.2 mm;

in the step 6), the machining allowance of finish machining is 0 mm;

in the step 7), the machining allowance of finish machining is 0 mm;

in the step 8), the machining allowance of the semi-finishing is 0.1 mm;

in the step 9), the machining allowance of the semi-finishing is 0.1 mm;

in the step 10), the machining allowance of finish machining is 0 mm;

in the step 11), the machining allowance of finish machining is 0 mm;

in the step 12), the machining allowance of rough machining is 0.1 mm;

in step 13), the finishing allowance is 0 mm.

Further, in the step 8), a deep processing five-axis milling mode is adopted, a specified point is made above a processing surface to determine the orientation of a cutter shaft, the feed speed is 900mm/min, and the rotating speed of a main shaft is 3000 r/min.

And 9) adopting a variable contour milling mode to make a specified point above the machined surface to determine the orientation of the cutter shaft, wherein the feeding speed is 600mm/min, and the rotating speed of the main shaft is 3000 r/min.

And step 10), adopting a deep processing five-axis milling mode to make a specified point above a processing surface to determine the orientation of a cutter shaft, wherein the feed speed is 900mm/min, and the rotating speed of a main shaft is 6000 r/min.

And 11), adopting a variable contour milling mode to make a specified point above the machined surface to determine the orientation of a cutter shaft, wherein the feed speed is 600mm/min, and the rotating speed of a main shaft is 6000 r/min.

In the invention, modeling and processing path planning can be carried out based on UG NX11.0 software.

The working principle of the processing method is as follows:

1. and carrying out three-dimensional modeling on the impeller part through UG software, and generating a two-dimensional engineering drawing.

2. The three-dimensional model and the engineering drawing carry out numerical control machining analysis on the impeller part, and a set of simple and convenient machining process which is reasonable, meets the actual machining requirement and meets the machining precision is designed through analysis.

3. And selecting a proper cutter, a reasonable processing mode and a correct processing cutter path through UG software, and performing numerical control processing simulation on the impeller part.

4. And analyzing the simulation result, optimizing the simulation result to form an efficient processing mode, and then generating the G code.

Compared with the prior art, the invention has the following characteristics:

1) the structure of the small-size impeller is designed, and the problems of complex structure, stress defect and the like caused by the splicing mode of a plurality of parts are avoided by the integrated forming mode.

2) The impeller is machined by the five-axis numerical control machine tool, the steps of blank pretreatment, modeling, tool path planning, rough machining, semi-finish machining, finish machining and the like are included, local high-precision milling of the impeller can be achieved, the impeller machining method is applicable to machining of impellers with various parameters, and the impeller machining method has the advantages of being high in machining efficiency, high in precision, good in finished product quality and the like.

3) The invention realizes the high-precision milling processing of the small-size impeller, can realize the impeller processing without a formed milling cutter and a special machine tool compared with a hobbing method and a powder metallurgy method in the prior art, has the characteristics of high processing efficiency, high precision and the like, and widens the processing method of the impeller.

4) The processing technology has wide application range, can process the parts which can not be processed by a general five-axis numerical control machine tool or can be processed at one time, and can process various complex impeller free curved surfaces.

5) The method has the advantages of high quality, more flexible processing technology, flexible matching of the processed impeller parts by using various cutters, capability of completing complex cutter path tracks and great improvement on the surface production processing quality.

6) The processing technology of the invention has the advantages of high efficiency, no need of multiple debugging and clamping for the workpiece in the complex angle for re-positioning, time saving, greatly reduced error, saved expensive cost for installing a tool clamp and the like for positioning the workpiece in place and greatly improved processing efficiency.

Drawings

FIG. 1 is a schematic structural view of an impeller in the embodiment;

FIG. 2 is a schematic structural diagram of a convex round bar material in the embodiment;

FIG. 3 is a schematic diagram of a blade processing tool path in the embodiment;

FIG. 4 is a schematic diagram of a groove side processing tool path in the embodiment;

FIG. 5 is a schematic view of a cutting path for machining the bottom surface of the groove in the embodiment;

the notation in the figure is:

the gear comprises a main shaft 1, a gear 2, a sleeve 3, blades 4, reinforcing ribs 5, a main shaft through hole 6, a tooth groove 7 and a groove 8.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.