A cold stamping forming process method of M-shaped parts

Abstract

The application discloses a cold stamping forming process method of an M-shaped part and relates to the technical field of automobile part sheet metal stamping. The method first forms the main surface shape of the middle region of the part by pressing the two side material sheets of the material sheet after uncoiling and blanking through the outer side pressing plate, then shapes the side wall of the M-shaped part to stamp the shape features of the side wall of the part, and finally punches some holes on the part and refines the product boundary. In order to ensure the quality of the part, according to the depth and opening angle of the side wall of the part, the shape of the side wall of the formed part of part products needs to be shaped twice sometimes. Compared with the drawing process scheme, the material utilization rate can be increased by about 15% under the condition that the quality of the part meets the requirements, thereby greatly reducing the production cost of the part; compared with the traditional forming scheme, the problem that the traditional forming scheme is prone to wrinkling is solved under the premise of keeping a high material utilization rate, and the quality of the part is improved.

Description

Technical Field

[0001] This invention relates to the field of sheet metal stamping technology for automotive parts, specifically a cold stamping forming process for M-shaped parts. Background Technology

[0002] M-shaped parts refer to sheet metal parts with an M-shaped cross-section on the body of an automobile. They are commonly used in body reinforcement components, such as beams and gear shift / handbrake mounting plates. These parts are characterized by high strength, a complex shape on the main surface, difficulty in forming, the absence of flanges on the side walls, and difficulty in controlling springback during stamping. During cold stamping, they frequently exhibit quality defects such as cracking, wrinkling, twisting, and severe springback.

[0003] For the manufacturing of M-shaped parts, domestic enterprises currently mainly use two stamping forming methods: single-piece drawing and intermediate blanking with both sides forming. The main disadvantage of single-piece drawing is that the drawing process requires a large additional area, resulting in more stamping waste, low sheet metal utilization, and high production costs. However, because this method can form the entire shape of the part in one go during drawing, the part quality is relatively high. The main disadvantage of the traditional intermediate blanking with both sides forming process is that wrinkling is prone to occur when forming the middle shape of the part due to the lack of blanking material. At the same time, during the flanging and shaping of the sides, the parting line contour is not smooth, often resulting in wrinkling and uneven corner rounding. However, because this method requires less additional waste, the sheet metal utilization rate is high and the part production cost is low.

[0004] In summary, both traditional stamping processes for M-type parts suffer from the problem of not being able to simultaneously achieve both part quality and production cost. Summary of the Invention

[0005] The purpose of this invention is to provide a cold stamping forming process for M-shaped parts to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a cold stamping forming process for M-shaped parts, comprising the following steps:

[0007] S1. Uncoiling and blanking;

[0008] S2. The outer pressure plate presses down on both sides of the uncoiled and unloaded material sheet to form the main surface shape of the middle area of ​​the part for the first time.

[0009] S3. The sidewalls of the part undergo a second positive shaping process to make the shape of the sidewalls of the part approximate the shape of the final product;

[0010] S4. Perform a third side shaping on the sidewall of the part to stamp out the characteristic shape of the sidewall of the part;

[0011] S5. Punch out the holes on the part and finish the product boundary. The part stamping is now complete.

[0012] Preferably, depending on the depth of the sidewall and the opening angle of the part, two shaping processes are required when forming the sidewall shape of the part.

[0013] Preferably, all shape features of the part need to be formed through a first positive shaping, a second positive shaping, and a third side shaping.

[0014] Preferably, external pressure plates should be installed on both sides during the first positive shaping.

[0015] Preferably, during the first positive shaping, an external pressure plate is used to press the two sides of the material sheet to form the main surface shape of the middle area of ​​the part.

[0016] Preferably, during the first positive shaping, the convex rounded corners on both sides of the part are formed by the outer pressure plate.

[0017] Preferably, the angle between the sidewall and the stamping direction during the second positive forming is between 35° and 45°.

[0018] Preferably, during the third lateral shaping, the angle of the shaping wedge is between 55° and 70°.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] The stamping forming process of this invention overcomes the shortcomings of traditional drawing processes, such as large process supplementation area, high production waste, low material utilization, and high unit production cost, while ensuring part quality. Compared with the drawing process, this process can improve part material utilization by more than 15%. Compared with the traditional intermediate blanking and side-forming scheme, it solves the wrinkling problem of parts in the traditional forming scheme, ensuring part quality. Through the invented process technology, both low cost and high quality requirements of M-type sheet metal part stamping production can be achieved, improving the competitiveness of enterprise production. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the shape of the M-type part to which the process technology solution of the present invention is applicable;

[0022] Figure 2 for Figure 1 Cross-sectional view of the structure at point AA of the inner product;

[0023] Figure 3 Schematic diagram of the process scheme of this invention;

[0024] Figure 4 This is a schematic diagram of the first forming process of the present invention;

[0025] Figure 5This is a schematic diagram of the second forming process of the present invention;

[0026] Figure 6 This is a schematic diagram of the third forming process of the present invention;

[0027] Figure 7 This is a schematic diagram of the precision edge punching process of the present invention.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1—Side fine trimming;

[0030] 2—Side punch;

[0031] 3—Positive punch;

[0032] 4—Sheet material;

[0033] 5—Positive punch;

[0034] 6—Product shape after the first molding;

[0035] 7—Shape after the second molding;

[0036] 8—Shape after the third molding;

[0037] 9—Side trimming;

[0038] 10—First forming die;

[0039] 11—First forming of the outer pressure plate;

[0040] 12—First forming punch;

[0041] 13—Sheet material before the first forming;

[0042] 14—Second forming punch;

[0043] 15—Second forming die;

[0044] 16—Second forming pressure plate;

[0045] 17—Sheet material before the second forming;

[0046] 18—Third forming punch;

[0047] 19—Third forming die;

[0048] 20—Third forming pressure plate;

[0049] 21—Sheet material before the second forming;

[0050] 22—Side trimming;

[0051] 23—Side punch;

[0052] 24—Punching hole. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0054] This invention provides a technical solution: a cold stamping forming process for M-shaped parts, comprising the following steps:

[0055] S1. Uncoiling and unloading; this process achieves separation and unloading.

[0056] S2. The outer pressure plate presses down on both sides of the uncoiled and unloaded material sheet, forming the main surface shape of the middle area of ​​the part for the first time, punching out the unfolded material sheet shape 13 before part forming. This process is the first forming of the part, forming the main surface shape of the middle area of ​​the part, such as... Figure 4 As shown. During this forming process, the outer pressure plates 11 on both sides of the upper die first contact the sheet material 13 on the die cavity 10 under the action of the slide block on the press, forming the convex rounded corners on both sides of the part, while pressing the sheet material. Then, the upper die continues to move downward, and the forming punch 12 in the middle contacts the sheet material 13, and together with the die cavity 10, forms the shape of the middle area of ​​the part. At this time, the shape of the middle area of ​​the M-shaped part is formed.

[0057] S3. The sidewalls of the part undergo a second positive shaping process to bring their shape closer to the final product shape. This process is the second forming of the part—positive flanging shaping—forming the transition shape of the sidewalls on both sides of the part, such as... Figure 5 As shown. During this forming process, the upper pressure plate 16, driven by the slide block on the press, first contacts the sheet 17 on the punch 14, pressing down the shape of the middle area of ​​the part to prevent the part from shifting during flanging. Then, the upper die continues to descend, and the flanging forming dies 15 on both sides contact the sheet 13, and together with the punch 14, form the transition shape of the side walls of the part, preparing for the final forming in the next process.

[0058] S4. Perform a third side-shaping process on the sidewalls of the part to stamp out the characteristic shape of the sidewalls. This process is the third forming of the part—side-shaping—forming the final shape of the two sidewalls of the part, such as... Figure 6As shown. During this forming process, the upper pressure plate 20, driven by the slide block on the press, first contacts the sheet 21 on the punch 18, pressing down the shape of the middle area of ​​the part to prevent the part from shifting during side forming. Then, the upper die continues to descend, and the flange forming dies 19 on both sides contact the sheet 21, and together with the punch 18, form the final shape of the side walls of the part. At this point, the entire shape of the M-shaped part is formed.

[0059] S5. Punching out holes on the part and finishing the product boundary. This process involves edge trimming and punching, punching out side holes 23 and front holes 24 on the part, and finishing the edge 22 of the part's partial boundary. Figure 7 As shown. The stamping of the part is now complete.

[0060] In this embodiment, depending on the depth of the sidewall and the opening angle, two shaping processes are required when forming the sidewall shape of the part to avoid wrinkling defects in the middle area of ​​the part.

[0061] In this embodiment, during the first positive shaping, external pressure plates are set on both sides. During the first positive shaping, the external pressure plates are used to press the material sheet on both sides to form the main surface shape of the middle area of ​​the part. The upper mold part is pressed by external pressure plates on both sides first, and then the upper mold punch moves down to form the shape features of the middle area of ​​the part, thereby ensuring the quality of the middle area of ​​the part.

[0062] In this embodiment, during the first positive shaping, the convex rounded corners on both sides of the part are formed by the outer pressure plate. In order to avoid wrinkling of the convex rounded corners on both sides of the part during the subsequent flanging shaping, a portion of the convex rounded corners are also formed by the outer pressure plate of the upper mold during this shaping.

[0063] In this embodiment, the angle between the sidewall and the stamping direction during the second forward forming is between 35° and 45°, and the angle of the forming wedge during the third side forming is between 55° and 70°. Since the shape of the part differs significantly from the final product shape after the first forming, if the flanging and forming are completed in one go, the forming amount is large, the flanging process is uncontrollable, and wrinkling is likely. Therefore, an intermediate forming process is added. First, the sidewall of the part formed in the first forming is flanged and formed to an angle of 35° to 45° with the stamping direction, and then this angled surface is side-formed to the product shape using a wedge at 55° to 70°. These two forming processes shape the sidewall of the part, reducing the forming amount per process and effectively controlling the springback of the sidewall, thus ensuring the quality of the part.

[0064] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative and not exhaustive. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A cold stamping forming process for an M-shaped part, characterized in that: Includes the following steps: S1. Uncoiling and blanking; S2. First positive shaping: The outer pressure plates on both sides of the upper mold first contact the material sheet on the die under the action of the slide block on the press, forming the convex rounded corners on both sides of the part, while pressing the two sides of the material sheet. Then, the upper mold continues to move down, and the forming punch in the middle contacts the material sheet, and together with the die, forms the main surface shape of the middle area of ​​the part. S3. Perform a second positive shaping on the sidewalls of the part to make the shape of the sidewalls of the part close to the shape of the final product; S4. Perform a third side shaping on the side wall of the part to stamp out the characteristic shape of the side wall of the part. At this point, the entire shape of the M-shaped part is formed. S5. Punch out the holes on the part and finish the product boundary of the part. The part stamping is completed. During the first shaping process, the rounded corners on both sides of the part are formed by the outer pressure plate to prevent wrinkling of the rounded corners on both sides of the part during the subsequent flanging and shaping. During the second positive shaping, the angle between the sidewall and the stamping direction is between 35° and 45°.

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