Machining method of thin-wall cylinder with composite angle characteristic

Abstract

The invention relates to a machining method for a thin-wall cylinder with a composite angle characteristic, belongs to the technical field of machining, and solves the problem that a small-size cylinder with an inner cavity with the composite angle characteristic is difficult to machine in the prior art. The invention discloses a machining method for a thin-wall cylinder with composite angle characteristics. The machining method comprises the steps that the cylinder is fixed to a machine tool rotary table (A axis) through an inner cavity machining clamping tool and is positioned and aligned; the machine tool turntable is fixed on the machine tool worktable (B shaft); the required composite angle is fitted by rotating the A shaft and the B shaft, and the long-arm right-angle milling head is matched to realize the processing of the composite angle characteristic of the inner cavity of the barrel. According to the machining method, the non-linkage five-axis machine tool can be used in cooperation with the special tool and the milling head, machining of the small-size barrel with the inner cavity having the composite angle characteristic is achieved, the requirement for machining equipment is lowered, operation is relatively easy, the machining precision is controllable, the machining cost is greatly reduced, and the machining method is suitable for large-scale production and large-scale popularization.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, and in particular to a processing method for a thin-walled cylinder with compound angle characteristics. Background Art

[0002] At present, various flight products and weapon products in the fields of aerospace, weapons and equipment have put forward higher requirements for mobility, long endurance and lightweight. Additive molding of large and complex thin-walled parts is widely used. Its characteristics are small inner cavity space, complex structure, thin wall, weak rigidity and easy deformation. These characteristics make it difficult to locate and clamp in the process of parts processing and manufacturing, low processing efficiency, long cycle, deep cavity and small space of parts are difficult to process, high processing cost and high equipment requirements.

[0003] At present, more and more complex thin-walled parts are formed by additive manufacturing. Compared with traditional casting and machining solutions, the machining removal amount is small, and non-matching surfaces are directly additively molded. However, the inner cavity structure is relatively complex and the inner cavity depth of the part is deep, which makes it difficult to process some features of the inner cavity of the part.

[0004] At present, five-axis linkage machine tools are mostly used at home and abroad to process deep cavities and small space compound angle features. However, the above processing method has high requirements on equipment, uncontrollable processing costs and high requirements on the operating level of operators. It is not suitable for large-scale production or the processing cost is unacceptable.

[0005] Therefore, how to achieve low-cost, efficient and precise processing of thin-walled cylindrical parts, deep cavities, and small space compound angle features has become an urgent problem to be solved. Summary of the invention

[0006] In view of the above analysis, an embodiment of the present invention aims to provide a processing method for a thin-walled cylinder with compound angle features, so as to solve at least one of the problems that the thin-walled cylinder with compound angle features is difficult to position and clamp during the processing and manufacturing process, the processing efficiency is low, the cycle is long, and the deep cavity and small space features of the parts are difficult to process.

[0007] The present invention discloses a method for processing a thin-walled cylinder with a compound angle feature, wherein the cylinder is fixed on a machine tool turntable and positioned and aligned by using an inner cavity processing clamping tool, wherein the rotating axis of the machine tool turntable is an A axis;

[0008] The machine tool turntable is fixed on the machine tool workbench, and the machine tool workbench rotation axis is the B axis;

[0009] At the same time, the A-axis and B-axis are adjusted to fit the required compound angle, and the long-arm right-angle milling head is used to realize the processing of compound angle features of the cylinder cavity;

[0010] The special milling head is a long-arm right-angle milling head;

[0011] The inner cavity processing clamping tool consists of a circular base, a screw, an annular upper plugging plate and a fastening nut; a circular boss 405 and a core shaft hole 403 are arranged at the center of the circular base, and a positioning pin 401 is arranged at the edge of the circular boss 405; the circular base annular platform is evenly distributed with connecting screw holes 402; and a reference groove 404 is arranged at the edge of the circular base.

[0012] Specifically, the effective length of the long-arm right-angle milling head arbor is ≥620 mm, the arbor diameter is ≤90 mm, and the right-angle milling head arbor forms a fixed angle of 90° with the milling head.

[0013] Specifically, the inner diameter of the cylinder is ≥140 mm.

[0014] Specifically, the inner diameter of the annular upper blocking disk is larger than the diameter of the long-arm right-angle milling head and the diameter of the tool rod.

[0015] The method specifically comprises the following steps:

[0016] S1: Designing an additive blank according to the structure of the cylinder, and preparing the additive blank by 3D printing process;

[0017] S2: Rough machining the additive blank to obtain a semi-finished cylinder;

[0018] S3: Fix the semi-finished cylinder with the external surface processing clamping tool, and finely process the external surface features of the semi-finished cylinder;

[0019] S4: Use the inner cavity processing clamping tool to fix the rough-machined blank, and cooperate with the special milling head to fine-machine the inner cavity feature 203 of the semi-finished cylinder to obtain the finished cylinder.

[0020] Specifically, the design principle of the additive blank in step S1 is: no allowance is set for non-matching assembly surfaces, an allowance of ≥ 2 mm is set for the shape, end face and both end stoppers, inner cavity platform, sinker, and hole, and no allowance is set in the inner cavity skin weight reduction area.

[0021] Specifically, the specific operation of step S2 is: the fitter aligns according to the reserved process boss for additive manufacturing and draws a rough machining reference line; aligns according to the drawn reference line and rough-machines the end faces at both ends of the cylinder and the inner stoppers at both ends.

[0022] Specifically, in step S3, a small cutting amount processing method is adopted when processing the outer surface of the cylinder.

[0023] Specifically, the specific operation of step S4 is to use the inner cavity processing clamping tool to fix the cylinder on the machine tool turntable and position it, and the machine tool turntable axis is the A axis; the machine tool turntable is fixed on the machine tool worktable, and the machine tool worktable axis is the B axis; at the same time, the A axis and the B axis are adjusted to fit the required composite angle, and the long-arm right-angle milling head is used to make the right-angle milling head and the processed inner cavity feature 203 in a vertical relationship, thereby fine-machining the composite angle feature of the inner cavity of the cylinder.

[0024] Specifically, the method can be implemented using a non-linked five-axis machine tool or a horizontal machining center.

[0025] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0026] 1. The processing of compound angle features of the inner cavity of small-sized cylinders has been realized. At present, for the compound angle features of the inner cavity of large-sized cylinders or special-shaped parts, five-axis milling heads or five-axis linkage machine tools with right-angle milling heads are generally used for processing. On the one hand, the equipment requirements are relatively high, the processing cost is high, and the requirements for operators are relatively strict; on the other hand, due to the large size of five-axis milling heads and ordinary milling heads and the short length of the tool rod, it is difficult to realize the processing of compound angle features of the inner cavity of small-sized cylinders.

[0027] The present invention uses a special inner cavity processing clamping tool to fix the cylinder on the machine tool turntable (A axis) and position and align it. The turntable is fixed on the machine tool worktable (B axis). At the same time, the A axis and the B axis are adjusted to fit the required compound angle. In conjunction with a long-arm right-angle milling head, the compound angle characteristics of the inner cavity of the cylinder can be processed. Since the radial dimensions of the milling head and the tool rod of the special long-arm right-angle milling head are small, and the axial dimensions of the tool rod are large, in conjunction with the inner cavity clamping tool annular upper blocking disk (entering the inner cavity of the cylinder from the annular inner ring), the inner cavity compound angle characteristics of small-sized and deep cavities can be processed. In addition, since only a non-linked five-axis machine tool / horizontal machining center can meet the processing needs, the processing cost and the requirements for operators are also significantly reduced. (For some inner cavity features with special angles, processing can also be achieved on a four-axis machine tool or machining center. The special angle refers to the angle that can be fitted by rotating the A axis or the B axis alone.)

[0028] 2. The inner cavity processing clamping tool disclosed in the present invention is not easy to damage the cylinder, especially the thin-walled cylinder. The inner cavity processing clamping tool disclosed in the present invention adopts the method of applying pressure from the end faces on both sides and positioning the cylinder by excessive tightening. Compared with the traditional clamping device that applies pressure from the outside of the cylinder to fix, it is not easy to damage the cylinder or cause the cylinder to deform. And through the design of positioning pins, core shaft holes, reference grooves, etc., the cylinder (especially the rotating body) is effectively prevented from sliding, rotating, eccentricity, etc. during the clamping process, which effectively improves the processing accuracy and yield rate.

[0029] 3. Under the premise of ensuring structural accuracy, the material consumption is reduced, and the processing content and processing cycle are reduced. The present invention adopts an additive manufacturing method (generally referring to 3D printing technology) for a thin-walled cylindrical blank with compound angle characteristics. The non-processing area of ​​the inner cavity adopts direct additive molding without leaving any allowance, reducing the processing content and processing cycle, and using a reserved process boss for rapid alignment of the rough machining benchmark. By designing effective positioning and benchmark transfer of tooling, the difficulty of clamping and alignment is reduced, the overall rigidity of the workpiece is improved, and the surface accuracy and wall thickness index requirements are guaranteed.

[0030] 4. Low equipment / tooling requirements, simple process flow, suitable for large-scale production. The customized tooling and milling head involved in the present invention have simple structure and are easy to process, so that they can be used to implement the processing method disclosed in the present invention; considering that the difficulty of transformation / assembly on the original machine tool is low and good processing effect can be achieved, it has considerable economic benefits and is suitable for large-scale production and large-scale promotion.

[0031] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0033] Figure 1 This is a schematic diagram of the structure of the barrel additive blank in Example 1;

[0034] Figure 2 It is a schematic diagram and a cross-sectional view of the cylinder structure in Example 1;

[0035] Figure 3 This is a schematic diagram of the clamping tooling and assembly for external surface processing;

[0036] Figure 4 This is a schematic diagram of the clamping tooling and assembly for inner cavity processing;

[0037] Figure 5 This is a front view of the long-arm right-angle milling head in Example 1;

[0038] Figure 6 This is a schematic diagram of the cooperation between the inner cavity processing clamping tool and the long-arm right-angle milling head in Example 1.

[0039] Reference numerals:

[0040] 101-front end reference boss; 102-rear end reference boss; 201-positioning groove; 202-ring rib; 203-inner cavity feature; 204-docking port; 205-rear end stop; 206-front end stop; 401-positioning pin; 402-connecting screw hole; 403-core shaft hole; 404-reference groove; 405-circular boss. DETAILED DESCRIPTION

[0041] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0042] The present invention discloses a method for processing a thin-walled cylinder with a compound angle feature, wherein the cylinder is fixed on a machine tool turntable and positioned and aligned by using an inner cavity processing clamping tool, wherein the rotating axis of the machine tool turntable is an A axis;

[0043] The machine tool turntable is fixed on the machine tool workbench, and the machine tool workbench rotation axis is the B axis;

[0044] At the same time, the A-axis and B-axis are adjusted to fit the required compound angle, and the long-arm right-angle milling head is used to realize the processing of compound angle features of the cylinder cavity;

[0045] The special milling head is a long-arm right-angle milling head.

[0046] The present invention uses a special inner cavity processing clamping tool to accurately and firmly position the cylinder on the machine tool turntable (A-axis) of the horizontal machining center and position and align it. The turntable is fixed on the machine tool workbench (B-axis), and the A-axis and B-axis are adjusted to fit the required compound angle. In conjunction with the long-arm right-angle milling head, the compound angle characteristics of the inner cavity of the cylinder can be processed; and because the radial dimensions of the milling head and the tool rod of the special long-arm right-angle milling head are small and the axial dimension of the tool rod is large, the compound angle characteristics of the inner cavity of small-sized and deep cavities can be processed.

[0047] Specifically, during processing, a special long-arm right-angle milling head is installed on the machine tool spindle and follows the machine tool spindle to move in the X\Y\Z directions. The right-angle milling head tool is installed at 90° (0° installation means the right-angle milling head tool is perpendicular to the B-axis of the machine tool worktable). At the same time, the A-axis and B-axis are adjusted so that the characteristic processing plane of the inner cavity platform (ie, the fitting angle) is perpendicular to the tool, and then the operation can be performed according to conventional milling processing specifications.

[0048] Specifically, the inner cavity processing clamping tool is composed of a circular base, a screw rod, an annular upper blocking disk and a fastening nut. The circular base and the annular upper blocking disk cooperate with the screw rod and the fastening nut to achieve the fixation of the cylinder through tight fit.

[0049] Furthermore, a circular boss and a core shaft hole are arranged at the center of the circular base, and a positioning pin is arranged at the edge of the circular boss; connecting screw holes are evenly distributed on the annular platform of the circular base; and a reference groove is arranged at the edge of the circular base.

[0050] The outer diameter of the circular boss matches the inner diameter of the barrel port (specifically matches the inner diameter of the front end port and / or the rear end port of the barrel, and can be flexibly selected according to the required processing direction). The function of the boss is to prevent the barrel from being eccentric and sliding; the core shaft hole and the fixing screw hole (matching the fastening bolts) are used to connect with the A-axis turntable of the machine tool to ensure that they are coaxial and firmly connected with the A-axis turntable, so that the tooling and the barrel can rotate 360° following the A-axis turntable of the machine tool; the locating pin is used to fix and position the barrel to prevent the barrel from rotating during the milling process, resulting in reduced processing accuracy or defective products; the reference groove is used to fix and position with the machine tool.

[0051] The inner diameter of the annular upper blocking plate should be larger than the diameter of the long-arm right-angle milling head arbor and the diameter of the milling head. Under the premise of ensuring the clamping effect, the inner diameter of the annular upper blocking plate should be as large as possible so that the milling head can extend into the cylinder to process the inner cavity features.

[0052] Specifically, the special milling head is a long-arm right-angle milling head with a longer tool bar and a smaller milling head diameter and tool bar diameter (such as Figure 5 As shown in the figure, the above design is conducive to the milling head entering the narrow and elongated inner cavity space to realize the processing of complex features. It is worth emphasizing that based on the material strength of the tool bar and the strength of the required processing material, the length of the tool bar should not be too long, so as to avoid the tool bar breaking due to shear force during the processing process, which may cause danger. In actual operation, for cylindrical parts with significantly longer inner cavity depths, the complex internal features can be processed from the front and rear ports respectively, which can significantly reduce the depth that the milling head needs to penetrate into the cylindrical part.

[0053] Specifically, the length of the long-arm right-angle milling head arbor is ≥620mm, the arbor diameter is ≤90mm, and the arbor of the right-angle milling head forms a fixed angle of 90° with the milling head. The milling head and arbor of the specially made long-arm right-angle milling head have smaller radial dimensions and a larger axial dimension, which can realize the processing of composite angle features of small-sized and deep cavities; the arbor of the right-angle milling head forms a fixed angle of 90° with the milling head to ensure the accuracy of processing. In actual implementation, the length of the arbor should not be infinitely extended and the diameter should not be too small, so as to avoid insufficient mechanical strength of the arbor, resulting in breakage during processing.

[0054] Specifically, the inner cavity diameter of the cylinder is ≥140mm. The method can realize fast and accurate processing of the inner cavity composite angle feature of the inner cavity diameter of the cylinder ≥140mm. The diameter of the cylinder is determined according to the size of the special milling head. If the diameter of the cylinder is too small, it is not conducive to the rotation, movement and cutting of the milling head in the inner cavity, and it is difficult to realize the processing of composite features.

[0055] The processing method specifically comprises the following steps:

[0056] S1: Designing an additive blank according to the structure of the cylinder, and preparing the additive blank by 3D printing process;

[0057] S2: Rough machining the additive blank to obtain a semi-finished cylinder;

[0058] S3: Fix the semi-finished cylinder with the external surface processing clamping tool, and finely process the external surface features of the semi-finished cylinder;

[0059] S4: Use the inner cavity processing clamping tool to fix the rough-machined blank, and cooperate with the special milling head to fine-machine the inner cavity features of the semi-finished cylinder to obtain the finished cylinder.

[0060] Specifically, the use of 3D printing technology to prepare the additive blank in step S1 helps to reduce processing content and processing cycle, and can also save materials.

[0061] Specifically, the design principle of the additive blank in step S1 is: no allowance is set on non-matching assembly surfaces to reduce the later processing content and processing cycle, and the allowance is set ≥ 2mm for the shape, end face and both end stoppers, inner cavity platform, sinker, and hole, so that the processing area has allowance processing during fine processing, thereby ensuring the assembly accuracy of the product; in addition, since the processing allowance of the additive blank is relatively small, the milling processing amount in actual production is reduced, avoiding mechanical fatigue or excessive wear of the cutter head, and is also beneficial to improving the processing accuracy.

[0062] Preferably, the designed barrel additive blank has no margin in the inner cavity, and the outer surface, the inner stop side wall, and the inner cavity composite features all have a margin of 2.5mm, and the end faces at both ends have a margin of 6mm (one of the barrel additive blank design examples is as follows Figure 1 shown).

[0063] Specifically, the specific operation of step S2 is: the fitter aligns according to the reserved process boss for additive manufacturing, and draws rough machining horizontal and symmetric reference lines; and draws rough machining end surface lines according to non-machined surfaces such as inner cavity ring ribs.

[0064] Preferably, in step S2, the cylinder (additive blank) is roughly milled on both end faces and the stoppers on both ends according to the reference line marked by the fitter, with a single-side allowance of 1 mm. The size of the stopper is required to be consistent with the outer size of the circular boss of the clamping tool for external surface processing to ensure a small clearance between the part and the clamping tool. After processing is completed, lines are engraved on the end faces and sides as a reference for external surface processing.

[0065] Specifically, the exterior surface processing clamping tooling is composed of upper and lower blocking plates and a pull rod. The specific structure and assembly effect are as follows: Figure 3As shown in the figure, the inner sides of the upper and lower plugging plates are provided with circular bosses, and the center of the circular bosses is provided with a core shaft hole. The outer side of the circular bosses matches the inner diameter of the semi-finished cylinder port and is used to position the semi-finished cylinder; the lower plugging plate is fastened to the T-slot of the machine tool workbench by bolts and T-blocks.

[0066] Specifically, in step S3, a small cutting amount processing method is used when processing the outer surface of the cylinder. Since the cutting depth and width are small, the corresponding cutting force will also be reduced, which helps to reduce the deformation of the workpiece during processing, and is particularly suitable for processing parts with poor rigidity, such as the thin-walled cylinder described in the present invention. In addition, the small cutting amount processing method is conducive to maintaining a small tool and workpiece deformation, reducing residual stress, and helping to improve processing accuracy.

[0067] Specifically, in step S3, the semi-finished cylinder is first fixed by using the external surface processing clamping tool, the wall thickness is measured, and the program zero point is fine-tuned according to the wall thickness; then the external surface features of the cylinder are fine-machined.

[0068] Preferably, in step S3, the cylinder (additive blank) is fixed by using an external surface machining clamping tool, the reference line is aligned, and a trial cutting of the circumferential holes is performed using a five-axis (non-linked) machining center. The program machining zero point is adjusted according to the trial cutting results to ensure uniform cutting of the holes; a small diameter round nose milling cutter is used to machine the external surface, and a small cutting amount is used to prevent excessive cutting force from causing excessive surface accuracy.

[0069] Specifically, the specific operation of step S4 is to first fix the turntable (A-axis) on the machine tool workbench (B-axis) through keyways and bolts, and then use the turntable A-axis center spindle and the inner cavity clamping tool to accurately position through fine milling of the spindle hole, and fix the inner cavity processing clamping tool to the machine tool A-axis through the circumferential fixing screw holes (matching the fastening bolts) and position and align, and then fix the workpiece to the inner cavity clamping tool through the workpiece inner stop, positioning groove and screw bolts, and at the same time adjust the A-axis (45° in the embodiment) and the B-axis (3° in the embodiment) to cooperate with the long-arm right-angle milling head, so that the right-angle milling head tool is perpendicular to the processed inner cavity features, and then the plane, cone, hole and other complex angle features of the cylinder inner cavity are finely processed; after the right-angle milling head tool is perpendicular to the processed inner cavity features, the subsequent specific processing process can be carried out with reference to the conventional milling processing process specifications.

[0070] Example 1

[0071] The test part blank selected by the present invention is formed by titanium alloy additive manufacturing. The cylinder body is a body of revolution with an outer diameter of 306 mm, a height of 605 mm, and a thinnest wall thickness of 2 mm. There are four circular holes, sinks, holes, platforms and other composite angle features evenly distributed around the cylinder body. The angle between the feature and the end face is 3°, and the four features are evenly distributed at 45°. The center of the circular hole is about 252 mm from the end face. The schematic diagram of the part is as follows: Figure 2shown.

[0072] The best embodiment of the present invention will be described in further detail below in conjunction with the accompanying drawings.

[0073] (1) According to the structure of the cylinder, the processing area and the distribution of the processing allowance, the cylinder additive blank (such as Figure 1 shown).

[0074] The processing allowance is reasonably distributed according to the technical requirements. Non-matching assembly surfaces are directly additively molded without setting any allowance. The allowance for the processing surfaces such as the outer shape, end face, stoppers at both ends, inner cavity platform, sinker, holes, etc. is 2mm. No allowance is set in the weight reduction area of ​​the inner cavity skin to reduce the processing cycle as much as possible.

[0075] (2) The fitter aligns the cylinder according to the reserved process bosses and draws the horizontal and symmetrical reference lines of the cylinder.

[0076] There are 4 circular holes distributed on the outer shape of the cylinder. In order to quickly determine the angular reference of the cylinder, process bosses with a height of 5mm and a width of 5mm are reserved on the front and rear ends of the combined additive blank. The horizontal and symmetrical reference lines of the cylinder are aligned and marked according to the process bosses. The end face lines at both ends are determined and marked according to the non-machined feature annular rib surface inside the cylinder along the axial direction, thereby determining the rough machining reference.

[0077] (3) Use the external surface processing clamping tool to clamp and locate the rough milling shape, measure the wall thickness, and fine-tune the program zero point according to the wall thickness to ensure the wall thickness meets the technical requirements.

[0078] When machining the outer surface of the cylinder, the outer surface machining clamping tooling is used for positioning and alignment. When machining the outer surface, firstly, the contours of the circular holes around the cylinder are trial-cut to ensure uniform removal. At the same time, a small-diameter round nose milling cutter with a small cutting depth is used to machine the outer surface. The wall thickness is measured multiple times during the machining process, and the machining zero point is fine-tuned according to the wall thickness data to ensure uniform wall thickness around the cylinder. After determining the final machining zero point, the outer surface, holes, two end faces, stoppers and other features are fine-machined.

[0079] The exterior surface is processed by clamping tooling for positioning and alignment, and a five-axis machining center is used to finely process the butt end face, butt inner stop, and butt circulation hole of the combined cylinder under one clamping condition to ensure machining accuracy.

[0080] (4) The cylinder body is positioned and aligned using the inner cavity machining clamping tooling, and the horizontal machining center cooperates with the right-angle milling head to fine-process the inner cavity sink, platform, hole and other composite angle features (such as Figure 6 shown).

[0081] There are four evenly distributed circular holes, countersunk tables, holes, platforms and other composite angle features around the cylinder, among which the angle between the feature and the end face is 3°, and the four features are evenly distributed at 45°. First, the inner cavity processing clamping tool and the semi-finished cylinder are accurately positioned and clamped through the stoppers and positioning grooves at both ends, and then the tool and the semi-finished cylinder are positioned and connected with the A-axis of the horizontal machining center turntable through the mandrel and screws, so that it can also rotate 360° with the turntable. Secondly, the right-angle milling head is installed 90° laterally on the machine tool spindle, and the inner cavity processed features are in a 90° vertical relationship with the right-angle milling head by rotating the B-axis of the horizontal machining center worktable (3°) and the A-axis of the turntable (45°). After the right-angle milling head tool is in a vertical relationship with the processed inner cavity features, the subsequent specific processing process can be carried out in accordance with the conventional milling process specifications, thereby realizing the rapid and precise processing of deep cavity composite angle features.

[0082] The present invention provides a processing and manufacturing method for a thin-walled cylinder with compound angle characteristics. First, an additive manufacturing method is used to realize the forming of a cylinder blank, thereby reducing the processing area and processing allowance of the cylinder; then, the outer surface processing clamping tool is used for clamping and positioning, so as to realize the processing of the outer surface, stopper, hole and other features of the cylinder; finally, the inner cavity processing clamping tool is used for positioning and clamping, and a horizontal machining center cooperates with a right-angle milling head to fine-process the composite angle sink and hole features inside the cylinder, thereby realizing the rapid and accurate processing and manufacturing of a complex, deep cavity, composite angle feature thin-walled cylinder.

[0083] This intellectual achievement has solved many problems in actual production, especially the processing of thin-walled cylindrical parts with compound angle inner cavity features can be realized without the use of five-axis linkage machine tools, which greatly reduces the processing cost, has significant economic benefits, and has strong application prospects.

[0084] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for processing a thin-walled cylinder with compound angle characteristics, characterized in that: The cylinder is fixed on the machine tool turntable and positioned and aligned by using an inner cavity processing clamping tool, and the machine tool turntable axis is the A axis; The machine tool turntable is fixed on the machine tool workbench, and the machine tool workbench rotating axis is the B axis; At the same time, the A-axis and B-axis are adjusted to fit the required compound angle, and the long-arm right-angle milling head is used to realize the processing of compound angle features of the cylinder cavity; The special milling head is a long-arm right-angle milling head; The inner cavity processing clamping tool consists of a circular base, a screw, an annular upper blocking plate and a fastening nut; a circular boss (405) and a core shaft hole (403) are arranged at the center of the circular base, and a positioning pin (401) is arranged at the edge of the circular boss (405); the circular base annular platform is evenly distributed with connecting screw holes (402); and a reference groove (404) is arranged at the edge of the circular base.

2. The processing method according to claim 1, characterized in that: The effective length of the long-arm right-angle milling head arbor is ≥620mm, the arbor diameter is ≤90mm, and the right-angle milling head arbor forms a fixed angle of 90° with the milling head.

3. The processing method according to claim 1, characterized in that: The inner cavity diameter of the cylinder is ≥140 mm.

4. The processing method according to claim 1, characterized in that: The inner diameter of the annular upper blocking disk is larger than the diameter of the long-arm right-angle milling head and the diameter of the tool rod.

5. The processing method according to any one of claims 1 to 4, characterized in that: The specific steps include: S1: Designing an additive blank according to the structure of the cylinder, and preparing the additive blank by 3D printing process; S2: Rough machining the additive blank to obtain a semi-finished cylinder; S3: Fix the semi-finished cylinder with the external surface processing clamping tool, and finely process the external surface features of the semi-finished cylinder; S4: Use the inner cavity processing clamping tool to fix the rough-machined blank, and cooperate with the special milling head to fine-machine the inner cavity features (203) of the semi-finished cylinder to obtain the finished cylinder.

6. The processing method according to claim 5, characterized in that: The design principle of the additive blank in step S1 is: no allowance is set for non-matching assembly surfaces, an allowance of ≥ 2mm is set for the outer shape, end face and both end stoppers, inner cavity platform, sinker, and hole, and no allowance is set for the inner cavity skin weight reduction area.

7. The processing method according to claim 5, characterized in that: The specific operation of step S2 is: the fitter aligns according to the reserved process boss for additive manufacturing and draws a rough machining reference line; aligns according to the drawn reference line and rough-machines the end faces at both ends of the cylinder and the inner stoppers at both ends.

8. The processing method according to claim 5, characterized in that: In step S3, a small cutting amount processing method is adopted when processing the outer surface of the cylinder.

9. The processing method according to claim 5, characterized in that: The specific operation of step S4 is to use the inner cavity processing clamping tool to fix the cylinder on the machine tool turntable and position it, and the machine tool turntable axis is the A axis; the machine tool turntable is fixed on the machine tool workbench, and the machine tool workbench axis is the B axis; at the same time, the A axis and the B axis are adjusted to fit the required composite angle, and the long-arm right-angle milling head is used to make the right-angle milling head and the processed inner cavity feature (203) in a vertical relationship, thereby fine-machining the composite angle feature of the inner cavity of the cylinder.

10. The processing method according to any one of claims 1 to 9, characterized in that: The method can be implemented by using a non-coordinated five-axis machine tool or a horizontal machining center.

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