CN112589142A

CN112589142A - Integral eccentric reverse-scribing cutter and method

Info

Publication number: CN112589142A
Application number: CN202011611905.4A
Authority: CN
Inventors: 沈晓良; 凌超强; 卫滨
Original assignee: BAODING HEAVY INDUSTRY CO LTD
Current assignee: BAODING HEAVY INDUSTRY CO LTD
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2021-04-02

Abstract

The invention relates to an integral eccentric reverse scribing tool and a method for machining a phi 90 sinking platform plane by replacing the existing reverse scribing machining mode with a reverse scribing tool, wherein the right side of the reverse scribing tool is a tool bar clamping part 1, a BT50 side fixed tool handle is installed, the tool bar is a middle transition section part, the left side is an eccentric tool head part, and the cross section size of the tool head is smaller than phi 52; the cutter head is a cylinder, the upper side part of the cylinder is cut into a blade fixing part which consists of a concave arc wall and a convex arc wall, the blade is fixed on the concave arc wall, and the cutter bar is eccentrically connected with the cutter head. The advantages are that: firstly, the processing efficiency is greatly improved, and the working time of the existing single-hole processing is shortened from 300 seconds to 85 seconds; secondly, the processing quality is fundamentally ensured.

Description

Integral eccentric reverse-scribing cutter and method

Technical Field

The invention relates to an integral eccentric reverse-scribing tool and a method for machining a phi 90 sinking platform plane by replacing the conventional reverse-scribing machining mode with a reverse-scribing tool, belonging to the field of manufacturing of specific machining tools.

Background

The Rotor Center product is one of the key parts of a high-voltage motor designed by 500-strength ABB company in the world, and is mainly used for large generator sets of ships or other equipment. The rotor center is of a sleeve type structure, has the processing characteristics of large appearance and high size precision, the total height reaches 1550mm, the excircle diameter phi 1363mm and the net weight 8.4t, belongs to large shaft sleeve products, needs to be assembled outside a rotor shaft, has high requirements on the size precision, the shape and position precision and the roughness of a matching part, and has great difficulty in machining and detection. According to the traditional processing method, the process flow is complex, the production period is long, and the product quality cannot be guaranteed.

Disclosure of Invention

The design purpose is as follows: the defects in the background technology are avoided, and the integral eccentric reverse-scribing cutter and the method for machining the phi 90 sinking platform plane by replacing the existing reverse-scribing machining mode with the reverse-scribing cutter are designed.

The design scheme is as follows: the center of the rotor of the shaft sleeve type product is of a sleeve type structure, the processing characteristics of large appearance and high dimensional precision are realized, the total height reaches 1550mm, the diameter phi of the outer circle is 1363mm, and the net weight is 8.4t, so that the large-scale shaft sleeve type product belongs to. The product is used as an important part matched with a rotor shaft, the requirements on the dimensional accuracy and the form and position tolerance of a matched part are high, the dimensional accuracy tolerance is less than 0.09mm, the roughness is less than Ra1.6, and the roundness is within 0.03 mm; 120-phi 52 through holes are uniformly distributed on the circumference, the verticality requirement of the matching of the holes and the inner holes is less than 0.08, and the position requirement is less than 0.1.

The product is used as an important component of motor equipment, is assembled on the outer side of the rotor shaft through interference fit, and is combined with the rotor shaft into a whole to operate together, so that the requirement on the dimensional precision of an inner hole matching part is quite high, and the stability and the safety of the motor operation are directly influenced. In addition, 120 PCS-phi 52 through holes are uniformly distributed on the outer circle of the product for mounting a magnetic yoke of a high-voltage motor, and a phi 90 counter bore on the back surface is used as a fixed plane and needs to keep good planeness and verticality, so that the production period can be greatly prolonged if a plurality of through holes and counter bores are processed according to the traditional mode, and the quality cannot be guaranteed. Therefore, the existing through hole and counter bore processing method needs to be improved urgently, and the working procedures become more efficient and convenient on the premise of ensuring the product quality.

1. The inner hole of the project product phi 970H7 is used as a matching gear, the requirement on dimensional tolerance is high, the roundness requirement reaches within 0.03, a scientific and reasonable machining process needs to be formulated in consideration of the influence of cutting stress release on the roundness of the machined inner hole in the phi 52 through hole machining process, the deformation problem generated by side through hole machining is eliminated by a method of decomposing and refining the inner hole part machining process, and the high precision and high quality of the product are ensured.

2. The conventional processing flow of the product is to turn an outer circle and an inner hole firstly and then transfer the outer circle and the inner hole to a boring machine to process a 120 PCS-phi 52 through hole and an end face screw hole on the circumference. The cutting stress generated by processing such a large number of phi 52 through holes is likely to cause the deformation of the product, thereby causing the dimensional tolerance and roundness of the key gear of the inner hole to be out of tolerance. If the processing procedure is changed (firstly, the through hole on the circumference is processed, and then, the excircle and the inner hole are turned), the influence of the punching deformation on the inner hole can be eliminated, but the turning processing efficiency is reduced due to the intermittent cutting, and the surface quality and the position tolerance of the through hole cannot be guaranteed, so the turning, punching procedures and processes need to be refined and optimized.

4. The back of the phi 52 through hole on the circumference needs to be processed with a 120 PCS-phi 90 sink table, and because the counter bore is positioned on the inner wall of the hole, the traditional processing method adopts a counter-scribing mode, and the counter-scribing process is as follows: firstly, an operator controls an anti-scribing cutter bar to extend into a phi 52 through hole; secondly, another operator installs a reverse utility knife and adjusts the cutting diameter of the knife and then locks the knife; the reverse cutting tool reversely feeds and cuts; fourthly, removing the reverse scribing cutter after the counter bore is machined, and enabling the cutter bar to retreat to the safe distance of the hole opening; fifthly, the rest phi 90 counter bores are processed according to the steps. The processing mode not only has complicated steps and increases a large amount of labor intensity for operators, but also is very easy to cause the problem of product quality caused by improper operation and matching, and simultaneously, the production and processing efficiency is quite low. The design and manufacture of a special reverse scribing cutter are considered to change the original processing mode, so that the reverse scribing process is continuous and efficient, and the purposes of improving the product efficiency and reducing the quality problem risk are achieved. The invention designs an integral eccentric reverse-scribing cutter to replace the existing reverse-scribing processing mode to process a phi 90 sinking platform plane, and a reverse-scribing cutting numerical control program is programmed according to the cutter structure and the sinking platform size, so that the non-cutting movement such as cutter feeding, cutter retracting and the like is controlled to be continuous and efficient, and the cutting process is uniform and stable.

5. The key gear processing technology aspect: the dimensional tolerance of the inner hole phi 970H7 of the product matching gear is required to be 0.09mm, the roundness is required to be 0.03mm, the roughness Ra1.6 is less, and the dimensional accuracy requirements of the positions of other inner holes and outer circles are relatively low. The first step is as follows: semi-finish turning and leaving a margin of 1.5mm on a single side, standing and aging to eliminate the influence of cutting stress and prepare for subsequent finish machining; the second step is that: processing parts such as an inner hole and an outer circle with low size requirements to be different in size, such as a phi 1363 (-0.2 to-0.6) outer circle to be processed to be phi 1362.7, and a phi 970H7 inner hole to be phi 969 (a 1mm allowance is reserved); thirdly, transferring to a boring machine to process a phi 52 through hole, a phi 90 sinking table and screw holes at two ends; and fourthly, finally, transferring to the lathe again, and machining the inner hole phi 970H7 after correction. And (3) performing profile modeling finish turning on the phi 970H7 inner hole according to the size requirement, reprocessing after the inner hole is qualified, and finally ensuring the size requirement and the roughness requirement of the phi 970H7 inner hole by a modified abrasive belt grinding and polishing method. And after the phi 970 inner hole is machined, a meter needs to be printed to detect whether the concentricity of the rest inner holes and the excircle and the A reference is qualified or not, and if the concentricity is unqualified, a finish turning is needed to ensure that the concentricity meets the requirement. Although a secondary turning process is added, the influence of punching and cutting stress can be eliminated by increasing few working hours, and the high precision and the high quality of the product are ensured.

6. A special integral reverse scribing tool (see figures 1-2 and a real object figure 3) is designed to replace an original split reverse scribing tool to machine a 120-phi 90 counter bore, and an optimized shank diameter phi 26 and an optimized eccentric tool bit R33 are firstly calculated according to a phi 52 bore diameter and a counter bore face width 19. Secondly, in the aspect of cutter bar material selection, as the cutter bar is stretched in a hanging mode (8 times the diameter: the length/diameter of the cutter bar), GCr15 bearing steel is adopted, an eccentric structure is adopted to reach the maximum sectional area, the integral rigidity of the cutter bar is ensured, then the main deflection angle 0 degree of a traditional reverse scraper is adjusted to be 7 degrees to reduce reverse cutting force (the main deflection angle of a conventional reverse scraper is 0 degree, along with the increase of the cutting diameter, the contact area between a blade and a workpiece is larger, the corresponding cutting resistance is larger, if the main deflection angle is larger, the roughness and the planeness of the surface of a counter bore can be influenced, the main deflection angle 7 degrees is a reasonable main deflection angle obtained after verification, and finally, an arc interpolation program matched with the cutter bar is designed and used according to the size of the counter bore. The integral type reverse utility knife abandons the process of knife dismounting, greatly saves production labor force and improves production efficiency. The procedure designed aiming at the cutter meets continuous and efficient operation, simultaneously, the size of the sinking platform is easier to control, and the quality risk is greatly reduced. The design and development of the special tool and the program have considerable reference and reference value for processing products with similar counter bore requirements.

The technical scheme is as follows: an integral eccentric reverse scribing cutter is characterized in that the right side of the reverse scribing cutter is a cutter bar clamping part, a BT50 side fixed cutter handle is installed, the cutter bar is a middle transition section part, the left side of the reverse scribing cutter is an eccentric cutter head part, and the cross section size of a cutter head is smaller than phi 52; the cutter head is a cylinder, the upper side part of the cylinder is cut into a blade fixing part which consists of a concave arc wall and a convex arc wall, the blade is fixed on the concave arc wall, and the cutter bar is eccentrically connected with the cutter head.

Compared with the background art, the invention has the advantages that firstly, the processing efficiency is greatly improved, and the working time of the existing single-hole processing is shortened from 300 seconds to 85 seconds; secondly, the processing quality is fundamentally ensured.

Drawings

FIG. 1 is a schematic view of an integral eccentric anti-scribe tool.

Fig. 2 is a side view of fig. 1.

Fig. 3 is a photograph of the object of fig. 1 with the blade removed for review reference and deleted if not acceptable.

Fig. 4 is a numerical control program diagram.

Detailed Description

Example 1: reference is made to figures 1-3 of the drawings. An integral eccentric reverse-scribing cutter is characterized in that: the right side of the reverse scribing cutter is provided with a cutter bar clamping part 1, a BT50 side fixed cutter handle is installed, the cutter bar is a middle transition section part 2, the left side of the reverse scribing cutter is provided with an eccentric cutter head part 5, and the cross section size of the cutter head is smaller than phi 52; the cutter head is a cylinder, the upper side part of the cylinder is cut into a blade fixing part 4 consisting of a concave arc wall and a convex arc wall, the blade 3 is fixed on the concave arc wall, and the cutter bar is eccentrically connected with the cutter head. The concave arc wall is milled with a boss for supporting the blade, and the blade 3 is positioned on the boss and fixed with the concave arc wall.

The integral eccentric reverse scribing tool processing method comprises the steps of replacing a phi 52 through hole after being processed with the integral eccentric reverse scribing tool, wherein the right side of the tool is a tool bar clamping part, a BT50 side fixed tool handle is installed, a phi 26 tool bar is a middle transition section part, the left side of the tool bar is an eccentric tool head part, and the cross section size of the tool bit is smaller than phi 52; the first step is as follows: adjusting the center of the cutter head to be consistent with the center of the phi 52 through hole, and then adjusting the angle of the cutter, wherein the blade is in the horizontal direction; the second step is that: feeding, namely feeding the knife along the through hole until the knife head part is completely exposed; thirdly, tool setting, operating an arc interpolation numerical control program, expanding and rotating the cutter bar around a circle while rotating the cutter bar, and reversely feeding and cutting an arc surface by the cutter to form a phi 90 sinking platform; the fourth step: withdrawing the cutter, returning the cutter to the initial position and angle, keeping the center of the cutter head consistent with the center of the through hole and keeping the angle of the blade horizontal; the fifth step: and continuously processing other phi 90 sinking platforms according to the steps.

It is to be understood that: although the above embodiments have described the design idea of the present invention in more detail, these descriptions are only simple descriptions of the design idea of the present invention, and are not limitations of the design idea of the present invention, and any combination, addition, or modification without departing from the design idea of the present invention falls within the scope of the present invention.

Claims

1. An integral eccentric reverse-scribing cutter is characterized in that: the right side of the reverse scribing cutter is provided with a cutter bar clamping part (1) which is provided with a BT50 side fixed cutter handle, the cutter bar is a middle transition section part (2), the left side of the reverse scribing cutter is provided with an eccentric cutter head part (5), and the cross section size of the cutter head is smaller than phi 52; the cutter head is a cylinder, the upper side part of the cylinder is cut into a blade fixing part (4) consisting of a concave arc wall and a convex arc wall, a blade (3) is fixed on the concave arc wall, and the cutter bar is eccentrically connected with the cutter head.

2. The integral eccentric scribing tool according to claim 1, wherein: the concave arc wall is milled with a boss for supporting the blade, and the blade (3) is positioned on the boss and fixed with the concave arc wall.

3. A processing method of an integral eccentric reverse-scribing cutter is characterized in that: after phi 52 through holes are machined, the integral eccentric reverse scribing cutter is used, wherein the right side of the cutter is a cutter bar clamping part, a BT50 side fixed cutter handle is installed, a phi 26 cutter bar is a middle transition section part, the left side of the cutter bar is an eccentric cutter head part, and the cross section size of the cutter head is smaller than phi 52; the first step is as follows: adjusting the center of the cutter head to be consistent with the center of the phi 52 through hole, and then adjusting the angle of the cutter, wherein the blade is in the horizontal direction; the second step is that: feeding, namely feeding the knife along the through hole until the knife head part is completely exposed; thirdly, tool setting, operating an arc interpolation program, expanding and rotating the cutter bar around a circle while rotating the cutter bar, and reversely feeding the cutter to cut an arc surface to form a phi 90 sinking platform; the fourth step: withdrawing the cutter, returning the cutter to the initial position and angle, keeping the center of the cutter head consistent with the center of the through hole and keeping the angle of the blade horizontal; the fifth step: and continuously processing other phi 90 sinking platforms according to the steps.