Radial forming equipment for thin-walled cylindrical part and forming process of radial forming equipment

Abstract

The radial forming equipment for the thin-wall cylindrical part comprises a plane table top, and a plurality of sliding rails pointing to the center of the plane table top are arranged on the plane table top; the number of the flexible mechanisms is the same as that of the sliding rails, the flexible mechanisms are arranged in a one-to-one mode, the flexible mechanisms are provided with embedding structures capable of being embedded with the sliding rails to slide, and each flexible mechanism can be stressed to slide on the corresponding sliding rail through the embedding structures; the flexible mechanism comprises a shell, and a plurality of telescopic clamping needles which are arranged in parallel and can achieve locking and positioning are outwards arranged on the shell in the same direction. On the basis of the concept of flexible design and manufacturing, through the technological steps of blank making, appearance machining, profiling, forming and the like, the machining mode is remodeled, the flexible manufacturing mode of the soft-to-soft mode is designed, related structures and technologies of the mold are reduced, a flexible tool is used for flat replacement, and the manufacturing cost is reduced. And meanwhile, the effect that the same set of tool can be adopted for products of multiple models and varieties is achieved.

Description

Technical Field

[0001] The invention relates to the field of parts forming, in particular to radial forming equipment for thin-walled cylindrical parts and a forming process thereof. Background Art

[0002] Thin-walled cylindrical parts are generally based on the stamping process after sheet metal rolling and welding. The rolling process is completed through the processes of sheet metal raw material - cutting - rolling - welding into a cylinder - stamping and forming - the subsequent process. Due to the influence of the welding process, the welding area shrinks, the cross-section is severely deformed, and it is egg-shaped. The gap requirements for subsequent multi-part butt welding cannot be guaranteed. This type of part is severely deformed after welding, so special control of radial size and shape is required. Generally, the stamping process is used to achieve radial size and shape control.

[0003] The characteristics of the current stamping forming process determine the need for mold tooling. Traditional radial forming of rotating bodies or irregular cylindrical parts often adopts expansion process or spinning process. The materials of both male and female molds are mold steel. The process method is "hard-on-hard". The mold design and manufacturing costs are high, the cycle is long, and it is difficult to use multiple models together; even if hydraulic forming can achieve "hard-on-soft", which can reduce part of the mold manufacturing cost, such molds often need to go through cumbersome processes such as mold design, mold manufacturing, mold assembly, mold debugging, mold trial, and small batch production to confirm whether they are qualified. In addition, traditional expansion molds generally require dozens of parts to be processed and opened through the pressing action of the wedge module in the mold; it takes more than one month to process and manufacture a set of molds until they are assembled; the mold debugging cycle is long, and various quality problems often occur during the proofing process. The mold needs to be disassembled and repaired or even partially redesigned; the design cost, material cost, and labor cost are high; it is impossible to change the mold and use it together. The material of this type of mold is steel mold, and the structural size is fixed, which makes it difficult to change the mold and use it together.

[0004] That is, it still faces the problems of long cycle, high cost and difficulty in sharing and compatibility of multiple models. In view of this, the inventor conducted in-depth research on the above defects in the prior art, and thus the present case was created. Summary of the invention

[0005] The first object of the present invention is to develop a radial forming device suitable for thin-walled cylindrical parts with simple structure and reasonable design; The second object of the present invention is to provide a radial forming process for thin-walled cylindrical parts which has a simple process, low cost, is reusable and can be shared by multiple types.

[0006] To achieve the first purpose of the present invention, the present invention discloses a radial forming device for thin-walled cylindrical parts, a workbench, the workbench comprising a plane table top, the plane table top is provided with a plurality of sliding tracks pointing to the center of the plane table top; there are also flexible mechanisms which are the same in number as the sliding tracks and are arranged one by one, the flexible mechanisms are provided with an interlocking structure which can be engaged and slid with the sliding tracks, and each flexible mechanism can slide under force on the corresponding sliding track through the interlocking structure; a limiting groove is provided at the end of each sliding track close to the center, which is used to limit the final position of the flexible mechanism sliding toward the center; the flexible mechanism comprises a shell, the shell is provided with a plurality of parallel telescopic clamping needles which can realize locking and positioning in the same direction outwardly, the plurality of clamping needles are arranged in the form of multiple rows and columns, and the plurality of clamping needles face the middle of the plane table top.

[0007] Furthermore, the flat table top is provided with four sliding tracks, and four flexible mechanisms are provided on each sliding track.

[0008] Furthermore, each of the flexible mechanisms is provided with a clamping device that can be clamped on a flat table surface, so that the flexible mechanism can be clamped on the workbench.

[0009] Furthermore, the clamping device is provided with a positioning block behind each flexible mechanism. The positioning block is designed to have a hollow window in the center, and corresponding screw holes are provided on both sides of the sliding track. Two bolts / screws pass through the hollow window and are locked in the screw holes to fix the positioning block, thereby realizing the clamping effect on the flexible mechanism.

[0010] Furthermore, the sliding track is designed as a concave slide groove with a trapezoidal cross-section that is narrow at the top and wide at the bottom; a fitting structure is provided at the bottom of the flexible mechanism, and the fitting structure is designed as a protruding slide bar with a cross-section that matches the shape of the concave slide groove; the protruding slide bar is fitted into the concave slide groove to achieve fitting sliding of the flexible mechanism and the sliding track.

[0011] A forming process for a radial forming device for thin-walled cylindrical parts, specifically comprising: Step 1: Making a blank, making a prototype blank according to the final outer shape of the cylindrical part to be made, and the prototype blank is made of reusable materials or 3D printing; Step 2: Processing the shape, designing the part sheet according to the cylindrical part to be manufactured, and manufacturing the part sheet with the corresponding shape; curling the part sheet into shape, and welding at the seam to obtain the primary blank; Step 3: Profiling: slide all the flexible mechanisms of the workbench outward along the slide track to open the middle space of the flat table, place the processed prototype blank in the middle space of the flat table, and translate several profiling mechanisms to the middle space until the flexible mechanism is limited by the limit groove, and the clamping needles in multiple rows and columns are close to the outer contour of the prototype blank, and all the clamping needles are locked and positioned to achieve profiling; at this time, move the flexible mechanism outward along the slide track to take out the prototype blank; Step 4: Molding. Place the primary blank obtained in step 2 in the center of the workbench, translate / slide all flexible mechanisms toward the center until they are limited by the limiting grooves, and fix the flexible mechanisms; punch / extrude the primary blank so that the primary blank finally fits all the clamping needles to achieve outer contour profiling and realize the final molding of the cylindrical part; remove the flexible mechanism and take off the final cylindrical part.

[0012] Furthermore, in the step of processing the shape, the processing of the part sheet is calculated based on the material thickness and parameters of the profile used, and the processed part sheet is allowed to form the final cylindrical part style after pressure deformation in the subsequent stamping process.

[0013] Furthermore, the final cylindrical part is a rotating cylindrical part or an irregular cylindrical part.

[0014] Furthermore, the reusable material used in the prototype blank is a material with a low melting point, easy to recycle and having a certain strength after solidification, specifically a mixture of one or more of tin-bismuth alloy, bismuth-nickel alloy, tin-silver alloy, polyethylene or wax.

[0015] Furthermore, the process is suitable for manufacturing cylindrical parts with a thickness in the range of 0.5 mm to 1.5 mm and a molding pressure in the range of 10 MPA to 20 MPA.

[0016] Furthermore, in the step 4, rubber is placed in the primary blank, and the rubber is squeezed by a press to achieve extrusion in the primary blank and to form a cylindrical part.

[0017] Furthermore, in the step 4, a variable and adjustable hydraulic medium is used to perform hydraulic stamping into the primary blank to achieve the forming of the cylindrical part.

[0018] This patent is based on the concept of flexible design and manufacturing, and reshapes the processing method.

[0019] Process reshaping: In order to reduce costs, mold-related modules are reduced, and in terms of efficiency, flexible manufacturing links are used instead; Equipment reshaping: The mold design, manufacturing, assembly and debugging links are cancelled and replaced with flexible tooling, and at the same time, multiple models and varieties of products can use the same set of tooling.

[0020] It also has the following advantages: 1. Since the prototype is only used for profiling and does not need to withstand the high pressure of stamping, the hardness requirement of the prototype material is low, allowing the use of low-melting-point repeatable materials, especially for materials with low hardness such as wax. This greatly expands the selection range of prototype materials and reduces the production and manufacturing costs of the overall process. In particular, even if rework or correction is required, the repetitive production cost of these materials is low and the process is extremely simple, which greatly reduces the production cycle and production cost.

[0021] 2. Adopting the flexible manufacturing concept, the male and female molds of the mold are redesigned, and the rigid female mold is replaced by a multi-point telescopic mold, and the original rigid male mold is replaced by rubber. In this way, the design and manufacturing of the original mold are cancelled, the process is replaced, and rapid manufacturing and flexible manufacturing are realized, while meeting the mold change and common mold requirements of multiple types of products.

[0022] 3. The production methods of prototype blanks can be diversified, and can also be combined with 3D printing or the inner core + outer layer 3D printing mode. As 3D printing technology matures, the printed style has a good possibility of random trimming, which further makes the patented process particularly simple, and the styles used are diversified and the molding is convenient; the product model can also be directly digitally imported into the equipment, and the clamping needle in the profiling equipment (flexible structure) can automatically generate the required surface size according to the instructions. It can play a better role, further reduce costs and improve efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The detailed description given as non-limiting examples better explains what the invention consists of and how it can be implemented, and furthermore, refers to the accompanying drawings, in which: Figure 1 , 2 This is a schematic diagram of the use of the workbench in the embodiment of the present invention. Figure 1 , two ; Figure 3 , 4 is a schematic diagram of a flexible mechanism in an embodiment of the present invention Figure 1 , two ; Figure 5 It is a simple schematic diagram of a workbench in an embodiment of the present invention; Figure 6 , 7 8 is a schematic diagram of a prototype blank, a part sheet, and a primary blank in an embodiment of the present invention; Fig. 9 , 10 , 11, 12, 14, and 15 are schematic diagrams of process steps in an embodiment of the present invention; Fig.13 , 16It is a schematic diagram of the rubber block and the cylindrical parts in the embodiment of the present invention.

[0024] Description of labels: Workbench 1; flat table 2; sliding track 3; limiting groove 31; screw hole 32; flexible mechanism 4; interlocking structure 41; shell 42; clamping needle 43; clamping device 44; positioning block 5; hollow window 51; prototype blank 6; Part sheet 7; primary blank 8; rubber block 81; cylindrical part 9. DETAILED DESCRIPTION

[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] like Figure 1-16 As shown, a radial forming device for thin-walled cylindrical parts is provided with a workbench 1, and the workbench 1 includes a flat table top 2. In the present embodiment, the flat table top 2 is provided with four sliding tracks 3 pointing to the center of the flat table top 2; there are also four flexible mechanisms 4 arranged one by one with the sliding tracks 3, and the flexible mechanisms 4 are provided with an interlocking structure 41 that can be engaged and slid with the sliding tracks 3, and each flexible mechanism 4 can slide on the corresponding sliding track 3 under force through the interlocking structure 41; each sliding track 3 is provided with a limiting groove 31 at the end close to the center, which is used to limit the final position of the flexible mechanism 4 sliding toward the center; the flexible mechanism 4 includes a shell 42, and the shell 42 is provided with a plurality of parallel telescopic clamping needles 43 that can realize locking and positioning outward in the same direction, and the plurality of clamping needles 43 are arranged in the form of multiple rows and columns. In the present embodiment, the clamping needles of the flexible mechanism are arranged in a 10×10 manner, and the plurality of clamping needles 43 face the middle of the flat table top 2.

[0027] In this embodiment, the flexible mechanism 4 can be a flexible module product of Haiding Zhirou Technology (Suzhou) Co., Ltd. or a flexible fixture product of Matrix Company of Germany. This type of fixture is a relatively mature product on the market before the application of this patent. This type of product was sold on the market in the form of a fixture based on the clamping function before the application of this patent, and it has no effect on the stamping process. However, our research has found that its clamping force can reach 600 bar, which is completely suitable for the manufacture of cylindrical parts 9 with a thickness of 0.5mm-1.5mm and a molding pressure of 10MPA-20MPA. The clamping needle 43 of this type of product has the function of positioning and locking, which can just use this function for the profiling step of this patent, and further use this type of fixture product as a radial molding die for thin-walled cylindrical parts.

[0028] Each of the flexible mechanisms 4 is provided with a clamping device 44 that can be clamped on the flat table 2, and the flexible mechanism 4 is clamped on the workbench 1 under force. In this embodiment, the clamping device 44 is a positioning block 5 provided behind each flexible mechanism 4, and the positioning block 5 is designed to have a hollow window 51 at the center, and corresponding screw holes 32 are provided on both sides of the corresponding sliding track 3. Two bolts / screws / screws pass through the hollow window 51 and are locked in the screw holes 32 to fix the positioning block 5 and realize the clamping effect on the flexible mechanism 4.

[0029] In this embodiment, the sliding track 3 is designed as a concave sliding groove with a trapezoidal cross-section that is narrow at the top and wide at the bottom; a mating structure 41 is provided at the bottom of the flexible mechanism 4, and the mating structure 41 is designed as a protruding sliding bar with a cross-section matching the shape of the concave sliding groove; the protruding sliding bar is mated with the concave sliding groove to realize the mating sliding of the flexible mechanism 4 and the sliding track 3.

[0030] The above-mentioned forming process for the radial forming equipment of thin-walled cylindrical parts, wherein the final cylindrical part 9 is a rotating cylindrical part 9 or an irregular cylindrical part, is specifically: Step 1: Make the blank, such as Figure 6 As shown, a prototype blank 6 is manufactured according to the required external shape of the final cylindrical part 9, and the prototype blank 6 is manufactured using reusable materials or 3D printing; Step 2: Processing shape, such as Figure 7 , 8 As shown, the part sheet 7 is designed according to the cylindrical part 9 to be manufactured, and the part sheet 7 with the corresponding shape is manufactured, generally by ordinary lathe or CNC lathe; the part sheet 7 is curled into shape, and welded at the seam to obtain the primary blank 8; Step 3: Profiling, such as Fig. 9 As shown, all the flexible mechanisms 4 of the workbench 1 are slid outward along the slide track 3 to open the middle space of the flat table top 2, as shown in FIG. Fig.10 As shown, the processed prototype blank 6 is placed in the middle space position of the flat table 2, and several flexible mechanisms 4 are translated to the middle space position until the flexible mechanism 4 is limited by the limiting groove 31, and the multiple rows and columns of clamping needles 43 are respectively close to the outer contour of the prototype blank 6 to achieve profiling, and all the clamping needles 43 are locked and positioned; at this time, the flexible mechanism 4 is moved outward along the sliding track 3, and the prototype blank 6 is taken out, as shown in FIG. Fig.11 As shown, the clamping needle 43 still maintains the style after profiling positioning; Step 4: Forming, such as Fig.12 As shown, the primary blank 8 obtained in step 2 is placed in the center of the workbench 1, all the flexible mechanisms 4 are translated / slid toward the center until they are limited by the limiting groove 31, and the positioning block 5 is locked to fix the flexible mechanism 4, and the flexible mechanism 4 is fixed at a position against the limiting groove 31; Figure 13-14 As shown, stamping / extrusion is performed inside the primary blank 8 so that the primary blank 8 finally fits all the clamping needles 43 to achieve outer contour profiling. In this embodiment, rubber, such as nitrile rubber, is placed inside the primary blank 8, and the rubber is squeezed by a press machine. The elastic extrusion deformation of the rubber is utilized to achieve the extrusion effect inside the primary blank 8, thereby achieving the molding of the cylindrical part 9, as shown in FIG. Fig.14 Loosen the positioning block 5, remove the flexible mechanism 4, remove the final cylindrical part 9, as Fig.16 .

[0031] In the step of processing the shape in step 2, the processing of the part sheet 7 is calculated according to the material thickness and parameters of the profile used, that is, the processed part sheet 7 allows the final cylindrical part 9 style to be formed after pressure deformation in the subsequent stamping process, for example Figure 7 As shown, the part sheet 7 is in the shape of a fan, that is, the primary blank 8 is made from the fan, and at this time the primary blank 8 is in the shape of a truncated cone, such as Figure 8 As shown, the prototype blank 6 is subsequently punched to form a final rotating cylindrical part 9 having a cross section similar to a top hat shape, as shown in FIG. Fig.16 ; The style of the initial part sheet 7 is calculated from the final shape, which can be calculated based on its material thickness and various performance parameters, and will not be repeated here.

[0032] In the step 4, if Fig.13 The figure shows a designed rubber block 81, which is designed as a stack of gradually decreasing cylinders. The rubber block 81 is placed in a truncated cone-shaped primary blank 8. Since the rubber block 81 is more compatible with the truncated cone shape, it is easier for the rubber block 81 to generate a more uniform pressure on the outer shell of the primary blank 8 during the deformation process. In other embodiments, rubber blocks 81 of different shapes can also be designed according to the shape of the primary blank 8 to ensure that the wall of the primary blank 8 is subjected to uniform force when the rubber is stamped.

[0033] The reusable material used in the prototype blank 6 is a material with a low melting point, which is easy to recycle and has a certain strength after solidification, specifically a mixture of one or more of tin-bismuth alloy, bismuth-nickel alloy, tin-silver alloy, polyethylene or wax. Since the prototype blank 6 of this patent is only used for positioning the clamping needle 43 of the flexible mechanism 4, the positioning pressure is extremely small, so the requirements for the material hardness and strength of the prototype blank 6 are also very small. Based on this, it is very meaningful to use reusable materials, especially materials with a low melting point and a certain strength. This type of material is often very easy to recycle, and it is also easy to re-mold the prototype blank 6 into a new style. Therefore, the process cost can be greatly reduced and the process can be simplified in this step.

[0034] In other embodiments, variable and adjustable hydraulic medium may be used to perform hydraulic stamping in the primary blank 8 to achieve the forming of the cylindrical part 9 .

[0035] In some other embodiments, the combination of the flexible mechanism 4 and the sliding track 3 can also be designed to be other quantities, such as five sets, six sets, etc., mainly based on the fact that in actual applications, the arrangement numbers of the clamping needles 43 of the flexible mechanism 4 are different, and the final cylindrical parts 9 that need to be processed are also different. Technicians can match the appropriate number of flexible mechanisms 4 according to the actual product.

[0036] Due to the design of this patent, multi-needle and multi-point pressure molding is adopted, and the flexible mechanism 4 is a multi-point telescopic structure, so it is particularly suitable for use in product conditions where there are no strict requirements and demands on the appearance of the cylindrical part 9, and multi-needle and multi-point pressure molding is more suitable for cylindrical parts 9 with a radial tendency to smoothly transition, and is not suitable for parts products with drastic changes in radial local characteristics; and the appearance of the product obtained by this process will have local embossing, and in various embodiments, subsequent grinding or coating processes can be further performed, which will not be described separately here. Since there are no very detailed appearance requirements for the cylindrical parts 9 with a radial tendency to smoothly transition, it is allowed that when designing this process, each flexible mechanism 4 will not interfere at the critical point.

[0037] This patent is particularly suitable for the field of small batches. If some small batch products require a series of processes and equipment such as molds, the cost will be very high, and the average price of a single product will also be very high. However, the use of our patent allows small batch production of various types of cylindrical parts with simple processes and low costs.

[0038] The above embodiments and illustrations do not limit the product form and style of the present invention. Any appropriate changes and modifications made by ordinary technicians in the relevant technical field should be deemed to be within the patent scope of the present invention.

Claims

1. A radial forming device for thin-walled cylindrical parts, characterized in that: A workbench, which includes a flat table top, on which a plurality of sliding tracks pointing to the center of the flat table top are arranged; there are also flexible mechanisms, which are the same in number as the sliding tracks and are arranged one by one, and the flexible mechanisms are provided with an interlocking structure that can be engaged and slid with the sliding tracks, and each flexible mechanism can slide on the corresponding sliding track under force through the interlocking structure; a limiting groove is provided at the end of each sliding track close to the center, which is used to limit the final position of the flexible mechanism sliding toward the center; the flexible mechanism includes a shell, and the shell is provided with a plurality of parallel telescopic clamping needles that can achieve locking and positioning in the same direction outward, and the plurality of clamping needles are arranged in the form of multiple rows and columns, and the plurality of clamping needles face the middle of the flat table top.

2. A radial forming device for thin-walled cylindrical parts as claimed in claim 1, characterized in that: The flat table top is provided with four sliding tracks, and four flexible mechanisms are provided on each sliding track.

3. A radial forming device for thin-walled cylindrical parts as claimed in claim 1, characterized in that: Each of the flexible mechanisms is provided with a clamping device which can be clamped on a flat table surface, so that the flexible mechanism can be clamped on the workbench.

4. A radial forming device for thin-walled cylindrical parts as claimed in claim 3, characterized in that: The clamping device is a positioning block provided behind each flexible mechanism. The positioning block is designed to have a hollow window in the center. Corresponding screw holes are provided on both sides of the sliding track. Two bolts / screws pass through the hollow window and are locked in the screw holes to fix the positioning block, thereby realizing the clamping effect on the flexible mechanism.

5. A radial forming device for thin-walled cylindrical parts as claimed in claim 1, characterized in that: The sliding track is designed as a concave slide groove with a trapezoidal cross-section that is narrow at the top and wide at the bottom; a fitting structure is arranged at the bottom of the flexible mechanism, and the fitting structure is designed as a protruding slide bar with a cross-section that matches the shape of the concave slide groove; the protruding slide bar is fitted into the concave slide groove to achieve fitting sliding of the flexible mechanism and the sliding track.

6. A forming process for a radial forming device for thin-walled cylindrical parts, characterized in that: Step 1: Making a blank, making a prototype blank according to the final outer shape of the cylindrical part to be made, and the prototype blank is made of reusable materials or 3D printing; Step 2: Processing the shape, designing the part sheet according to the cylindrical part to be manufactured, and manufacturing the part sheet with the corresponding shape; curling the part sheet into shape, and welding at the seam to obtain the primary blank; Step 3: Profiling: slide all the flexible mechanisms of the workbench outward along the slide track to open the middle space of the flat table, place the processed prototype blank in the middle space of the flat table, and translate several profiling mechanisms to the middle space until the flexible mechanism is limited by the limit groove, and the clamping needles in multiple rows and columns are close to the outer contour of the prototype blank, and all the clamping needles are locked and positioned to achieve profiling; at this time, move the flexible mechanism outward along the slide track to take out the prototype blank; Step 4: Molding. Place the primary blank obtained in step 2 in the center of the workbench, translate / slide all flexible mechanisms toward the center until they are limited by the limiting grooves, and fix the flexible mechanisms; punch / extrude the primary blank so that the primary blank finally fits all the clamping needles to achieve outer contour profiling and realize the final molding of the cylindrical part; remove the flexible mechanism and take off the final cylindrical part.

7. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: In the step of processing the shape, the processing of the part sheet is calculated based on the material thickness and parameters of the profile used, and the processed part sheet is allowed to form the final cylindrical part style after pressure deformation in the subsequent stamping process.

8. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: The final cylindrical part is a rotating cylindrical part or an irregular cylindrical part.

9. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: The reusable material used in the prototype blank is a material with a low melting point, easy to recycle and having a certain strength after solidification, specifically a mixture of one or more of tin-bismuth alloy, bismuth-nickel alloy, tin-silver alloy, polyethylene or wax.

10. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: It is suitable for manufacturing cylindrical parts with a thickness of 0.5mm-1.5mm and a molding pressure of 10MPA-20MPA.

11. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: In the step 4, rubber is placed in the primary blank, and the rubber is squeezed by a press to achieve extrusion in the primary blank and to form the cylindrical part.

12. A forming process for a radial forming device for thin-walled cylindrical parts as claimed in claim 6, characterized in that: In the step 4, a variable and adjustable hydraulic medium is used to perform hydraulic stamping in the primary blank to achieve the forming of the cylindrical part.

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