Composite incremental forming tool head for hole forming and outward flanging of pipe fitting and / or sheet metal part and implementation method of composite incremental forming tool head for hole forming and outward flanging of pipe fitting and / or sheet metal part

Abstract

The invention provides a composite incremental forming tool head for hole making and outward flanging of pipe fittings and / or sheet metal parts and an implementation method, the tool head comprises a milling cutter, a forming fillet, a clamping area and an arc transition area, the milling cutter is used for hole making of sheet materials and pipe materials, the forming fillet is used for forward incremental forming of local materials so as to achieve outward flanging of holes, and the clamping area is used for clamping the clamping area. The clamping area is used for clamping of a clamp, and the two ends of the arc transition area are smoothly connected with the forming fillet and the clamping area correspondingly. Compared with the prior art, innovation is achieved on a machining tool head, rapid outward turning of holes with different diameters is achieved through an incremental forming method, the hole turning coefficient is greatly increased, and the method has important practical value for achieving flanging quality improvement and flexible manufacturing of pipe fittings and sheet metal parts; hole forming and flanging are integrated, the machining method is simple and easy to implement, a mold is not needed, a tool head does not need to be replaced, and great advantages are achieved in the aspects of manufacturing cost and period.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flanging tools for pipe and sheet metal parts, in particular to a composite incremental forming tool head for hole making and outward flanging of pipe and / or sheet metal parts and an implementation method. BACKGROUND

[0002] In the fields of automobiles, aerospace, biomedicine, etc., many key parts have outward flanging features that are prone to cracking in ordinary stamping, such as exhaust, fuel piping components in automobiles and aerospace, and many medical devices. How to achieve the best outward flanging forming effect at the lowest cost is a difficult problem in technical design.

[0003] Chinese patent application CN118437855A proposes a pipe flanging and expanding device, which flanges and expands the pipe to form a pipe with an outward flanging feature. Chinese patent CN117463854A proposes a forming method for pipe with flanging on both sides, which uses the principle of hydraulic forming, and after the bulging is completed, the top of the bulging area is cut off according to the size, and the flanging forming of the part is completed. Chinese patent CN220992560U proposes a titanium alloy sheet flanging die for aircraft, which can be used to stamp in the stamping direction using a traditional die to process a titanium alloy sheet flanging part that meets the requirements. However, the above methods can complete the flanging forming of pipe and sheet, but the die design is complex and the manufacturing cost is high. In order to realize flexible flanging forming of sheet and reduce cost, Cao et al. proposed a new flanging tool head based on sheet features and an implementation method in the literature "Experimental investigations on the forming mechanism of a new incremental stretch-flanging strategy with a featured tool" (Int J Adv Manuf Technol (2017) 92: 2953 -2964). The tool head includes a tool arm, a pressure ring, a parabolic forming surface, a straight wall forming surface, and a milling cutter at the end of the tool head. First, the sheet is fixed on the tooling, and a pad is placed under the sheet. A milling cutter is used to process the required circular hole, and then two forming surfaces are used to realize inward flanging of the sheet. The tool head and method can avoid the phenomenon of severe thinning in traditional incremental forming flanging process, and can realize inward flanging of the sheet without a die, but the tool head and method cannot realize outward flanging of the sheet and pipe, and the tool head needs to be customized according to the features. SUMMARY

[0004] The present application aims at overcoming the defects in the stamping forming and the traditional incremental forming, and provides a compound incremental forming tool head for hole forming and outward flanging of a pipe and / or sheet metal and an implementation method.

[0005] The present application aims at overcoming the defects in the stamping forming and the traditional incremental forming, and provides a compound incremental forming tool head for hole forming and outward flanging of a pipe and / or sheet metal and an implementation method. The first object of the present application is to provide a compound incremental forming tool head for hole forming and outward flanging of a pipe and / or sheet metal, comprising a milling cutter, a forming fillet, a clamping area and an arc transition area; the milling cutter is used for hole forming of a pipe and a sheet metal; the forming fillet is used for positive incremental forming of local material to realize outward flanging of a hole; the clamping area is used for clamping of a clamp; the milling cutter, the forming fillet, the arc transition area and the clamping area are sequentially connected.

[0006] Further, the arc transition area is smoothly connected with the forming fillet and the clamping area at two ends respectively.

[0007] Further, the milling cutter is a flat-end milling cutter, which has high machining efficiency and good rigidity, and the length range of the cutting edge is 20-30 mm and the radius range of the milling cutter is 10-15 mm.

[0008] Further, the forming fillet is used for outward flanging of a hole, and the radius range of the fillet is 0.5-10 mm.

[0009] Further, the clamping area is used for clamping of a clamp, and the length range is 100-150 mm and the radius range is 7.5-10 mm.

[0010] Further, the material of the compound incremental forming tool head is high-temperature alloy or hard alloy.

[0011] The second object of the present application is to provide an implementation method of compound incremental forming for hole forming and outward flanging of a pipe and / or sheet metal, which adopts the compound incremental forming tool head, and the method comprises the following steps. S1. According to the material properties and hole forming and flanging forming parameters of the pipe and / or sheet metal to be formed, the radius and length of the milling cutter and the forming fillet are determined. S2. According to the flanging height of the outward flanging area to be formed, the length of the vertical rod of the clamping area is determined. S3. According to the shape of the local area to be formed, the hole forming track and the outward flanging track of the compound incremental forming tool head are designed. S4. The milling cutter of the compound incremental forming tool head is made to perform hole forming along the hole forming track, and the compound incremental forming tool head needs to be rotated. S5, when the forming fillet shoulder of the compound incremental forming tool head is flush with the hole edge, the forming fillet is made to move along the outward flanging trajectory of the forming, the positive incremental forming of the pipe and / or sheet metal part is carried out, and the compound incremental forming tool head does not need to rotate; S6, the pipe and / or sheet metal part is formed into the required part shape through the accumulation of local deformation in the incremental forming process.

[0012] Further, in step S3, the hole making trajectory is a contour trajectory or a layer cutting trajectory.

[0013] Further, in step S3, the outward flanging trajectory is a spiral layer cutting trajectory.

[0014] Further, before step S4, the following steps are performed: The pipe and / or sheet metal part is fixed on the tooling, the end is clamped, and the pipe is provided with a cylindrical pad at both ends.

[0015] Further, the pipe is a round pipe.

[0016] Further, the sheet metal part is a sheet.

[0017] Further, the method comprises the following steps: S1, the radius and length of the milling cutter and the forming fillet are determined according to the material properties of the required formed pipe and / or sheet metal part and the hole making and flanging forming parameters; S2, the length of the vertical rod of the clamping area is determined according to the flanging height of the required outward flanging area; S3, the hole making trajectory and the outward flanging trajectory of the compound incremental forming tool head are designed according to the shape of the local area to be formed, the hole making trajectory is a contour trajectory or a layer cutting trajectory, and the outward flanging trajectory is a spiral layer cutting trajectory; S4, the sheet (sheet metal part) or the round pipe provided with a cylindrical pad at both ends is fixed on the tooling, and the end needs to be clamped; S5, the milling cutter of the compound incremental forming tool head is made to make holes along the hole making trajectory, and the compound incremental forming tool head needs to rotate; S6, when the forming fillet shoulder of the compound incremental forming tool head is flush with the hole edge, the forming fillet is made to move along the spiral outward flanging trajectory of the forming, the positive incremental forming of the pipe and / or sheet metal part is carried out, and the compound incremental forming tool head does not need to rotate; S7, the pipe and / or sheet metal part is formed into the required part shape through the accumulation of local deformation in the incremental forming process.

[0018] The application provides a compound incremental forming tool head for hole forming and outward flanging of pipe fittings and / or sheet metal fittings and an implementation method.

[0019] Compared with the prior art, the application has the following beneficial effects: 1) The compound incremental forming tool head for hole forming and outward flanging of pipe fittings and / or sheet metal fittings and the implementation method have the following advantages: compared with traditional stamping forming, the method realizes the integration of hole forming and flanging of holes with different diameters, is simple and easy to implement, does not need a die, and does not need to replace the tool head, and has great advantages in manufacturing cost and period.

[0020] 2) The compound incremental forming tool head for hole forming and outward flanging of pipe fittings and / or sheet metal fittings and the implementation method have the following advantages: compared with traditional incremental forming, the method pushes the material in the fillet to apply compressive stress, greatly improves the flanging coefficient, and effectively improves the hole flanging quality.

[0021] 3) The compound incremental forming tool head for hole forming and outward flanging of pipe fittings and / or sheet metal fittings and the implementation method have the following advantages: the method realizes innovation on the tool head, realizes the rapid outward flanging of holes with different diameters by using the incremental forming method, and has important practical value for flexible flanging manufacturing of various holes of pipe fittings and sheet metal fittings. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a schematic view of the cross-sectional structure of the tool head of the application; Figure 2 FIG. 2 is a schematic view of the hole forming process of the tool head of the application; Figure 3 FIG. 3 is a schematic view of the incremental forming and flanging process of the application on a round pipe fitting; Figure 4 Fig. 7 is a schematic view of a finished round tube product after forming according to the present application; Figure 5 Fig. 8 is a schematic view of a progressive forming and flanging process on a sheet metal part according to the present application; Reference signs: 1. milling cutter, 2. formed fillet, 3. clamping area, 4. arc transition area, 5. round tube, 6. tooling, 7. spacer, 8. sheet metal part. DETAILED DESCRIPTION

[0023] The present application will be described in detail below with reference to the drawings and specific embodiments. In the technical solution, components not explicitly described, material names, connection structures, control implementation methods, algorithms, and other features are considered as common technical features disclosed in the prior art.

[0024] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing", and other terms should be understood broadly, for example, can be fixed connection, or detachable connection, or integrated; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through an intermediate medium; can be internal communication of two elements or interaction between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0025] It should be noted that in the present application, relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, implementation method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, implementation method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, implementation method, article or device including the element.

[0026] The content of the present application will be further described in detail below in combination with specific embodiments and drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

[0027] EMBODIMENT Taking the round tube 5 and the sheet metal part 8 as an example, as shown in Fig. 8, the round tube 5 is placed on the sheet metal part 8, and the round tube 5 is gradually formed and flanged on the sheet metal part 8 by the tooling 6. Figure 1As shown, the embodiment provides a combined incremental forming tool head for hole forming and outward flanging of pipe and sheet metal parts, which comprises a milling cutter 1, a forming fillet 2, a clamping area 3 and an arc transition area 4.

[0028] The milling cutter 1 is one of the core parts to complete the hole forming and outward flanging combined incremental forming. According to the aluminum alloy pipe to be formed, the diameter is 60mm and the thickness is 1mm. The hole diameter to be processed is 30mm. The milling cutter is determined to be a flat-end milling cutter with a length of 25mm and a radius of 10mm. The flat-end milling cutter has high processing efficiency and good rigidity, which ensures that the tool head can realize hole forming in the forming area.

[0029] The forming fillet 2 is another core part to complete the hole forming and outward flanging combined incremental forming. The forming fillet is used for incremental forming flanging of the hole. The small fillet radius is 0.5mm and the large fillet radius is 5mm. The length between the end of the milling cutter 1 and the forming fillet is 5mm, and the length between the forming fillet and the arc transition area 4 is 15mm. The large fillet is close to the arc transition area 4, and the small fillet is close to the milling cutter 1. The large fillet and the small fillet are connected to ensure that the tool head can use the fillet to push the material and apply pressure stress to form the required shape of the part (the pipe 5 and the sheet metal part 8), greatly improve the flanging coefficient, and effectively improve the hole flanging quality.

[0030] The clamping area 3 is used to clamp the tool head, with a length of 100mm and a radius of 10mm, which ensures that the forming area of the tool head can be processed to the required forming position. At the same time, the length of the rod part cannot be too long, otherwise it will increase the moment and elastic deformation of the tool head, and in severe cases it will break the tool head.

[0031] The tool head must have sufficient rigidity and be made of advanced die materials such as high-temperature alloy or hard alloy, etc.

[0032] The embodiment further provides a method for processing a pipe 5 (metal pipe) and a sheet metal part 8 which requires hole forming and outward flanging combined incremental forming. The following pipe 5 and sheet metal part 8 incremental forming is an independent process, which includes the following steps: S1, according to the material properties and forming parameters of the pipe 5 and the sheet metal part 8 to be formed, determine the type of milling cutter 1, the length of the milling cutter 1, the radius of the milling cutter 1, the radius of the forming fillet 2, the length between the forming fillet 2 and the end of the milling cutter 1, the length between the forming fillet 2 and the arc transition area 4, the vertical rod length of the clamping area 3, and the material of the tool head; S2, according to the hole diameter of 30mm and the outward flanging height of 10mm in the outward flanging area, use UG software to design the hole forming trajectory and outward flanging trajectory of the tool head. The hole forming trajectory is a contour trajectory, and the outward flanging trajectory is a spiral layer cutting trajectory. After the trajectory is generated, machine tool simulation is performed to complete preliminary inspection of the trajectory. After export, NcViewer is used for re-inspection to ensure that the trajectory is correct, and then imported into the numerical control machine (CNC). S3, after the tool head and the running track (hole-making track and outward flanging track) are designed, the tool head is installed on the machine tool spindle through the clamping area 3, and the aluminum alloy sheet metal part 8 or the aluminum alloy pipe part 5 with the cylindrical pad 7 at both ends is fixed on the tool 6. According to the radius of the pipe part 5 being 30 mm, the radius of the cylindrical pad 7 is determined to be 28 mm and the length is 20 mm. The tool 6 is used to clamp both ends to prevent the forming effect from being unsatisfactory and the forming precision from being poor due to the movement of the part to be formed during the machining process; S4, the CNC machine tool is manually operated for centering, then the tool head is lifted, the machining program is introduced and the machine tool is started, the hole-making track is run, the tool head rotates, the milling cutter 1 is used for hole-making, and when the tool head is about to contact the pipe part 5 and the sheet metal part 8, the tool head rotation speed percentage is adjusted to 20%. After the first circle is completed, the rotation speed is adjusted to 100% to continue hole-making. The hole-making process is as shown in Figure 2 , Figure 2 The hole-making process of the sheet metal part 8 is the same. S5, after the hole-making is completed, the tool head stops rotating, the machine tool is manually operated to align the shoulder of the forming fillet 2 of the tool head with the edge of the hole, the machine tool is started, the outward flanging track is run, and the forming fillet 2 is positively formed. When the first circle is formed, the CNC machine tool feed speed percentage is adjusted to 50%, and after the first circle is formed, it is adjusted to 100% to complete the subsequent forming. When the flanging height is about 5 mm, the feed speed is adjusted to 30% to avoid flanging cracking. The progressive forming processes of the pipe part 5 and the sheet metal part 8 are as shown in Figure 3 、 Figure 5 , S6, after the local deformation is accumulated by the progressive forming, the pipe part 5 and the sheet metal part 8 are formed into the required part shape. After the forming is completed, the tool head is lifted, and the parts (the finished pipe part 5 and the finished sheet metal part 8 after the forming are completed) are taken down. The finished pipe part 5 after the forming is completed is as shown in Figure 4 , and the finished sheet metal part 8 after the forming is completed is the same.

[0033] The above description of the embodiments is for the convenience of the ordinary skilled person in the art to understand and use the invention. Those skilled in the art can easily make various modifications to these embodiments, and the general principles and methods described herein can be applied to other embodiments without creative labor. Therefore, the present application is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present application should be within the scope of protection of the present application.

Claims

1. A compound incremental forming tool head for tube and / or sheet metal hole formation and outward flanging, characterized in that Milling cutter (1), forming fillet (2), clamping area (3) and arc transition area (4) are included. The milling cutter (1) is used for pipe and plate material hole forming. The forming fillet (2) is used for local material positive progressive forming to realize hole outward flanging. The clamping area (3) is used for clamp clamping. The milling cutter (1), forming fillet (2), arc transition area (4) and clamping area (3) are sequentially connected.

2. The compound incremental forming tool head for hole making and outward flanging of tubular and / or sheet metal parts according to claim 1, characterized in that, The arc transition area (4) is smoothly connected with the forming fillet (2) and the clamping area (3) at both ends.

3. The compound incremental forming tool head for hole making and outward flanging of tubular and / or sheet metal parts according to claim 1, characterized in that, The milling cutter (1) is a flat end milling cutter, the length of the cutting edge is 20-30mm, and the milling cutter radius is 10-15mm.

4. The compound incremental forming tool head for hole making and outward flanging of tubular and / or sheet metal parts according to claim 1, characterized in that, The forming fillet (2) has a fillet radius of 0.5-10mm.

5. The compound incremental forming tool head for hole making and outward flanging of tubulars and / or sheet metal parts of claim 1, wherein, The clamping area (3) has a length of 100-150mm and a radius of 7.5-10mm.

6. The compound incremental forming tool head for hole making and outward flanging of tubulars and / or sheet metal parts of claim 1, wherein, The material of the composite progressive forming tool head is high-temperature alloy or hard alloy.

7. A method for performing combined hole flanging and hole forming of a tube and / or sheet metal part using the combined incremental forming tool head according to any one of claims 1 to 6, characterized in that The method comprises the following steps: S1, according to the material properties and hole forming, flanging forming parameters of the required formed pipe and / or sheet metal parts, the radius and length of the milling cutter (1) and the forming fillet (2) are determined; S2, according to the flanging height of the required outward flanging area, the length of the vertical rod of the clamping area (3) is determined; S3, according to the shape of the required local area, the hole forming track and outward flanging track of the composite progressive forming tool head are designed; S4, the milling cutter (1) of the composite progressive forming tool head moves along the hole forming track to form holes, and the composite progressive forming tool head needs to rotate; S5, when the shoulder of the forming fillet (2) of the composite progressive forming tool head is flush with the hole edge, the forming fillet (2) moves along the formed outward flanging track to perform positive progressive forming of the pipe and / or sheet metal parts, and the composite progressive forming tool head does not need to rotate; S6, through the local deformation accumulation in the progressive forming process, the pipe and / or sheet metal parts are formed into the required part shape.

8. A method of implementing tube and / or sheet metal hole flanging and combined incremental forming according to claim 7, characterized in that, In step S3, the hole forming track is a contour track or a layer cutting track.

9. The method of implementing tube and / or sheet metal hole flanging and combined incremental forming according to claim 7, characterized in that, In step S3, the outward flanging track is a spiral layer cutting track.

10. The method of implementing tube and / or sheet metal hole flanging and combined incremental forming according to claim 7, characterized in that, Before step S4, the following steps are performed: The pipe and / or sheet metal parts are fixed on the tool, the end is clamped, and the pipe is provided with a cylindrical pad at both ends.

Images