Methods for forming plate-shaped parts, drawing die assemblies and plate-shaped parts

Abstract

This application relates to the field of parts processing technology, and proposes a method for forming plate-shaped parts, a drawing die assembly, and a plate-shaped part. The plate-shaped part forming method includes: drawing a flat sheet using a first drawing die to obtain a first plate surface, a second plate surface, and a third plate surface connected in sequence. The first and second plate surfaces are staggered, and the connection position between the second and third plate surfaces forms a first rounded corner with a radius greater than 20t1, where t1 is the thickness of the flat sheet; and then drawing the third plate surface in reverse using a second drawing die to obtain a fourth plate surface. A storage bag is formed on the fourth plate surface, and the connection position between the second and fourth plate surfaces forms a second rounded corner with a radius smaller than that of the first rounded corner. The above-mentioned plate-shaped part forming method, through these two processes, avoids stamping marks from entering the visible area of ​​the product, thus solving the problem of stamping marks appearing in the visible area of ​​the plate part.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of part processing, in particular to a plate-shaped part forming method, a drawing die assembly and a plate-shaped part. BACKGROUND

[0002] Nowadays, the appearance aesthetic requirements of automobiles are getting higher and higher, and the requirements for the plate parts of the body-in-white are also getting more and more demanding, so the appearance quality requirements (especially the visible area) of the plate parts in the stamping forming process are also getting higher and higher.

[0003] At present, the plate parts are usually produced by directly drawing flat plate material and then forming by trimming. Due to the modeling requirements of the plate parts, this stamping process cannot meet the appearance requirements of the plate parts, and the visible area of the plate parts will appear stamping marks during the forming process, which need to be polished manually to eliminate the stamping marks. However, the effect after manual polishing is not ideal, and after the plate parts are painted, visible defects in appearance will still appear. SUMMARY

[0004] Therefore, the embodiments of the present application provide a plate-shaped part forming method, a drawing die assembly and a plate-shaped part to solve the problem that the visible area of the plate part will appear stamping marks.

[0005] The first aspect of the present application provides a plate-shaped part forming method, comprising:

[0006] The flat plate material is drawn and formed by using a first drawing die to obtain a first plate surface, a second plate surface and a third plate surface connected in sequence, the first plate surface and the third plate surface are arranged in a staggered manner, the connection position of the second plate surface and the third plate surface forms a first fillet, and the radius of the first fillet is greater than 20t1, wherein t1 is the thickness of the flat plate material;

[0007] The third plate surface is reversely drawn and formed by using a second drawing die to obtain a fourth plate surface, a material storage bag is formed on the fourth plate surface, the connection position of the second plate surface and the fourth plate surface forms a second fillet, and the radius of the second fillet is smaller than the radius of the first fillet.

[0008] The plate-shaped part forming method provided by the embodiments of the present application has the beneficial effects that: when the flat plate material is drawn and formed by using the first drawing die, the radius of the first fillet is greater than 20 times the thickness of the flat plate material, which can reduce the contact stress during stamping, thereby reducing the stamping marks; when the third plate surface is reversely drawn and formed by using the second drawing die, the material storage bag is formed on the fourth plate surface, and when the first fillet becomes the second fillet, the excess material can flow into the material storage bag. Through the above two processes, the stamping marks are avoided from flowing into the visible area of the product, and the problem that the visible area of the plate part will appear stamping marks is solved.

[0009] In some embodiments, the radius of the first fillet is 12-30 mm.

[0010] In some embodiments, the fourth panel includes a first panel segment and a second panel segment, a connecting position of the second panel and the first panel segment forms the second fillet, the storage package is on the second panel segment, and a distance between the storage package and the first panel segment is 3-12 mm.

[0011] In some embodiments, the width of the storage package is 3-12 mm; and / or, the height of the storage package is 3-12 mm.

[0012] In some embodiments, the draft angle of the storage package is 3°-12°.

[0013] In some embodiments, the storage package protrudes towards a direction of reverse draw forming.

[0014] A second aspect of the present application provides a draw die assembly applied to the panel part forming method as described in the first aspect. The draw die assembly includes a first draw die and a second draw die. The first draw die includes a first female die, a first male die and a first pressure piece. The first male die and the first pressure piece are both below the first female die. The first female die and the first pressure piece cooperate to press the edge of the flat plate material. The first female die and the first male die cooperate to form a first panel, a second panel, a third panel and a first fillet. The second draw die includes a second female die, a second male die, a second pressure piece and a third pressure piece. The second male die, the second pressure piece and the third pressure piece are all below the second female die, and the second male die is between the second pressure piece and the third pressure piece. The second pressure piece and the second female die cooperate to press the first panel and the second panel. The third pressure piece and the second female die cooperate to press part of the third panel. The second male die and the second female die cooperate to draw another part of the third panel to obtain a second fillet and a fourth panel provided with a storage package.

[0015] The draw die assembly adopts any one or more embodiments of the panel part forming method described above, and thus has the beneficial effects of the above embodiments, which will not be repeated here.

[0016] In some embodiments, the pressure force of the second pressure piece is greater than the pressure force of the third pressure piece.

[0017] In some embodiments, the draw die assembly further comprises a first nitrogen spring connected with the first blank holder to provide a blanking force to the first blank holder; and / or, the draw die assembly further comprises a second nitrogen spring connected with the second blank holder to provide a blanking force to the second blank holder; and / or, the draw die assembly further comprises a third nitrogen spring connected with the third blank holder to provide a blanking force to the third blank holder.

[0018] A third aspect of the present application provides a plate-shaped part made by the plate-shaped part forming method according to the first aspect.

[0019] The plate-shaped part adopts any one or more embodiments of the plate-shaped part forming method described above, and thus has the beneficial effects of the embodiments described above, which will not be repeated here.

[0020] The above description is only a summary of the technical solutions of the present application. In order to enable the technical means of the present application to be more clearly understood, and to be implemented according to the content of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application will be described. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or conventional technical description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without any creative labor.

[0022] Figure 1 is a structural schematic diagram of an existing plate-shaped part;

[0023] Figure 2 is Figure 1 is a structural schematic diagram of the plate-shaped part stamping forming;

[0024] Figure 3 is a flowchart of the plate-shaped part forming method provided by some embodiments of the present application;

[0025] Figure 4 is a structural schematic diagram of the plate-shaped part stamping forming provided by some embodiments of the present application;

[0026] Figure 5 is a structural schematic diagram of the first draw die before closing provided by some embodiments of the present application;

[0027] Figure 6 is a structural schematic diagram of the first draw die after closing provided by some embodiments of the present application;

[0028] Figure 7 is a structure schematic diagram of a second drawing die before closing provided by some embodiments of the present application;

[0029] Figure 8 is a structure schematic diagram of a second drawing die after closing provided by some embodiments of the present application.

[0030] The meaning of the mark in the figure is:

[0031] 10, first plate surface;

[0032] 20, second plate surface;

[0033] 30, third plate surface;

[0034] 40, first round corner;

[0035] 50, second round corner;

[0036] 60, first drawing die; 61, first die; 62, first punch; 63, first pressure piece; 64, first nitrogen spring;

[0037] 70, second drawing die; 71, second die; 711, concave part; 72, second punch; 721, convex part; 73, second pressure piece; 74, third pressure piece; 75, second nitrogen spring; 76, third nitrogen spring;

[0038] 80, flat plate material;

[0039] 90, fourth plate surface; 91, first plate segment; 92, second plate segment; 921, storage bag;

[0040] 200, plate-shaped part; 201, visible plate surface; 202, fixed plate surface; 203, round corner. DETAILED DESCRIPTION

[0041] The embodiments of the technical solutions of the present application will be described in detail below in combination with the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments of the present application, and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0043] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly specified and limited.

[0044] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0045] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after it.

[0046] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0047] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0048] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing", etc. should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanical connection, or it can be electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0049] At present, in the process of designing a drawing die, a flat blank is directly drawn and then cut and formed to produce a plate-shaped part. Due to the modeling requirements of the plate-shaped part, this stamping process cannot meet the appearance requirements of the plate-shaped part, and stamping marks will appear in the visible area during the forming process.

[0050] Please refer to Figure 1 , the plate-shaped part 200 is a C-pillar inner panel of a rear door window frame of a vehicle, the plate-shaped part 200 includes a visible panel surface 201 and a fixed panel surface 202, the visible panel surface 201 is not covered by other parts or ornaments, and stamping defects can be observed, and the fixed panel surface 202 is used to fix the plate-shaped part 200 on the vehicle body and cannot be cancelled or changed.

[0051] When the plate-shaped part 200 is stamped and formed, please refer to Figure 2 , ABCD is the cross section of the plate-shaped part 200, ABC is the cross section of the visible panel surface 201, CD is the cross section of the fixed panel surface 202, and ABCDE is the cross section of the process modeling, and the DE section is cut off to obtain the plate-shaped part 200, wherein the thickness of the plate-shaped part 200 is t, and the radius of the round corner 203 is R. Influenced by product modeling, t is usually less than 1 mm, and R is usually less than 8 mm, for example, R is 8 mm, t is 1 mm, and the radius R (8 mm) of the round corner 203 is much smaller than 20t (20 mm). During the stamping and forming process, a hardening line is generated at the round corner 203 (the smaller the radius R of the round corner 203, the more obvious the hardening line), and as the stamping proceeds, the material flows along the direction of D→C→B, and the hardening line generated by the round corner 203 gradually flows to the BC section of the visible panel surface 201, forming a stamping mark; the stamping mark is not easy to eliminate in the post-processing process, affecting the appearance quality of the product.

[0052] To solve the above problems, an embodiment of the first aspect of the present application provides a plate-shaped part forming method. Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 7 , the plate-shaped part forming method comprises:

[0053] S1, using a first drawing die 60 to draw and form a flat blank 80 to obtain a first panel surface 10, a second panel surface 20 and a third panel surface 30 connected in sequence, the first panel surface 10 and the third panel surface 30 are arranged in a staggered manner, and the connection position of the second panel surface 20 and the third panel surface 30 forms a first round corner 40, and the radius R1 of the first round corner 40 is greater than 20t1, wherein t1 is the thickness of the flat blank 80.

[0054] Optionally, the flat blank 80 is a metal plate.

[0055] The first panel 10, the second panel 20, and the third panel 30 are connected in sequence. It can be understood that the second panel 20 is connected between the first panel 10 and the third panel 30.

[0056] The first panel 10 and the third panel 30 are staggered, which can be understood as the first panel 10 and the third panel 30 not being on the same plane. Optionally, the first panel 10 and the third panel 30 are arranged in parallel or substantially parallel, and the second panel 20 is arranged at an angle.

[0057] The radius R1 of the first fillet 40 is greater than 20t1, that is, the radius R1 of the first fillet 40 is greater than 20 times the thickness of the flat plate 80. It can be understood that when t1 is 1mm, the radius of the first fillet 40 is greater than 20mm; when t1 is 0.8mm, the radius of the first fillet 40 is greater than 16mm; when t1 is 0.6mm, the radius of the first fillet 40 is greater than 12mm.

[0058] Among them, the first plate surface 10 corresponds to Figure 4 In section AB, the second plate surface 20 corresponds to Figure 4 In section BC, the third panel 30 corresponds to Figure 4 In segment IH, the first fillet radius is 40 degrees. Figure 4 The CI segment in the middle.

[0059] S2. The third plate surface 30 is reverse drawn using the second drawing die 70 to obtain the fourth plate surface 90, and a storage bag 921 is formed on the fourth plate surface 90. The connection position between the second plate surface 20 and the fourth plate surface 90 forms a second rounded corner 50, and the radius of the second rounded corner 50 is smaller than the radius of the first rounded corner 40.

[0060] The second drawing die 70 performs reverse drawing on the third plate surface 30. That is, the first drawing die 60 and the second drawing die 70 draw in opposite directions at the position of the third plate surface 30. For example, the first drawing die 60 draws the flat plate 80 downward to form the third plate surface 30, and the second drawing die 70 draws the third plate surface 30 upward to form the fourth plate surface 90.

[0061] During reverse drawing, the storage bag 921 allows excess material to enter, preventing stamping marks from flowing into the visible area of ​​the product and avoiding wrinkles in the CJD section.

[0062] It should be noted that the second fillet radius of 50 is the fillet radius that the product is ultimately intended to achieve.

[0063] The fourth panel corresponds to 90 degrees. Figure 4 In the JDEFGH segment, the second fillet radius is 50 degrees. Figure 4 The CJ segment in the middle. Plate-shaped parts correspond to... Figure 4In the ABCJD segment, after the second drawing die 70 finishes drawing, DEFGH is cut off at point D to obtain a plate-shaped part; where ABC segment is the visible plate surface of the plate-shaped part, and JD segment is the fixed plate surface of the plate-shaped part.

[0064] Among them, the length of the CJDEFGH segment is greater than or equal to the length of the CIH segment.

[0065] The beneficial effects of the plate-shaped part forming method provided in this application embodiment are as follows: When the first drawing die 60 is used to draw the flat sheet 80, since the radius of the first fillet 40 is greater than 20 times the thickness of the flat sheet 80, the contact stress during stamping can be reduced, thereby reducing stamping marks; when the second drawing die 70 is used to reverse draw the third sheet 30, since a storage bag 921 is formed on the fourth sheet 90, when the first fillet 40 becomes the second fillet 50, excess material can flow into the storage bag 921. Through the above two processes, stamping marks are prevented from flowing into the visible area of ​​the product, solving the problem of stamping marks appearing in the visible area of ​​the plate-shaped part.

[0066] In some embodiments, the radius R1 of the first fillet 40 is 12-30 mm.

[0067] Since the radius R1 of the first fillet 40 is greater than 20t1, when the radius R1 of the first fillet 40 is 12mm, t1 is less than 0.6mm; when the radius R1 of the first fillet 40 is 18mm, t1 is less than 0.9mm; when the radius R1 of the first fillet 40 is 24mm, t1 is less than 1.2mm; and when the radius R1 of the first fillet 40 is 30mm, t1 is less than 1.5mm.

[0068] The appropriate radius R1 of the first fillet 40 can be selected according to the thickness t1 of the flat material 80 to reduce the contact stress during stamping, thereby reducing stamping marks.

[0069] In some embodiments, the fourth plate surface 90 includes a first plate segment 91 and a second plate segment 92. The connection position between the second plate surface 20 and the first plate segment 91 forms a second rounded corner 50. The storage bag 921 is located on the second plate segment 92, and the distance between the storage bag 921 and the first plate segment 91 is 3-12mm.

[0070] The distance between the storage bag 921 and the first plate segment 91 is 3-12mm, that is, the distance between D and E is 3-12mm; it can be understood that the distance between the storage bag 921 and the first plate segment 91 can be 3mm, 5mm, 8mm, 10mm, 12mm, etc.

[0071] Among them, the first segment 91 corresponds to Figure 4 Middle JD segment, second board segment 92 corresponds Figure 5 to Figure 8After the DEFGH section, i.e. the second drawing die 70, is completed, the second plate section 92 is cut off to obtain the plate-shaped part.

[0072] Based on the above scheme, the distance between the storage bag 921 and the first plate segment 91 is designed to be 3-12mm. That is, the distance between the storage bag 921 and the first plate segment 91 is moderate, which not only facilitates the flow of material at CJD to the storage bag 921, but also facilitates the cutting off of the second plate segment 92 at D.

[0073] In some embodiments, the width of the storage bag 921 is 3-12mm and the height of the storage bag 921 is 3-12mm.

[0074] The width of the storage bag 921 can be considered as the horizontal distance from F to G, and the height of the storage bag 921 can be considered as the vertical distance from F to E.

[0075] Optionally, the width of the storage bag 921 can be 3mm, 5mm, 8mm, 10mm, 12mm, etc.; the height of the storage bag 921 can be 3mm, 5mm, 8mm, 10mm, 12mm, etc.

[0076] The width and height of the storage bag 921 can be the same or different.

[0077] In other embodiments, when the width of the storage bag 921 is 3-12mm, the height of the storage bag 921 can be greater than 12mm or less than 3mm; or, when the height of the storage bag 921 is 3-12mm, the width of the storage bag 921 can be greater than 12mm or less than 3mm; or, the width of the storage bag 921 can be greater than 12mm or less than 3mm, and the height of the storage bag 921 can be greater than 12mm or less than 3mm.

[0078] In some embodiments, the draft angle of the storage bag 921 is 3°-12°.

[0079] Among them, the draft angle refers to the inclination angle of the side wall of the storage bag 921. For example, the inclination angle of the EF segment is the draft angle.

[0080] It is understandable that the draft angle of the storage bag 921 can be 3°, 5°, 8°, 10° or 12°, etc.

[0081] Optionally, the draft angles of the two side walls of the storage bag 921 may be the same or different.

[0082] Based on the above scheme, the draft angle of the storage bag 921 is designed to be 3°-12°, which is beneficial for demolding.

[0083] In some embodiments, the storage bag 921 protrudes in the direction of reverse drawing. That is, the protruding direction of the storage bag 921 is the same as the drawing direction of the second drawing die 70 on the third plate surface 30.

[0084] The second aspect of this application provides a drawing die assembly for use in a plate-shaped part forming method as described in the first aspect.

[0085] Please refer to Figure 5 The drawing die assembly includes a first drawing die 60 and a second drawing die 70. The first drawing die 60 includes a first die 61, a first punch 62, and a first blank holder 63. The first punch 62 and the first blank holder 63 are both located below the first die 61. The first die 61 and the first blank holder 63 cooperate to press the edge of the flat sheet 80. The first die 61 and the first punch 62 cooperate to form the first sheet surface 10, the second sheet surface 20, the third sheet surface 30, and the first fillet 40. The second drawing die 70 includes a second die 71, a second punch 72, and a second blank holder 73. The second punch 72, the second pressing member 73, and the third pressing member 74 are all located below the second die 71, and the second punch 72 is located between the second pressing member 73 and the third pressing member 74. The second pressing member 73 and the second die 71 cooperate to press the first plate surface 10 and the second plate surface 20. The third pressing member 74 and the second die 71 cooperate to press a portion of the third plate surface 30. The second punch 72 and the second die 71 cooperate to draw another portion of the third plate surface 30 to obtain the second rounded corner 50 and the fourth plate surface 90 with a storage bag 921.

[0086] Among them, the first pressing component 63 is a pressing ring.

[0087] Optionally, the drawing die assembly further includes a first nitrogen spring 64, which is connected to the first pressure member 63 to provide a pressure force to the first pressure member 63. The first nitrogen spring 64 is located below the first pressure member 63 and provides an upward pressure force to the first pressure member 63. It is understood that the first nitrogen spring 64 may be fixedly connected to the first pressure member 63 or detachably connected to it.

[0088] The drawing die assembly also includes a second nitrogen spring 75, which is connected to the second pressure member 73 to provide a pressure force to the second pressure member 73. The second nitrogen spring 75 is located below the second pressure member 73 and provides an upward pressure force to the second pressure member 73. It is understood that the second nitrogen spring 75 can be fixedly connected to the second pressure member 73 or detachably connected to it.

[0089] The drawing die assembly also includes a third nitrogen spring 76, which is connected to the third pressure member 74 to provide pressure force to the third pressure member 74. The third nitrogen spring 76 is located below the third pressure member 74 and provides an upward pressure force to the third pressure member 74. It is understood that the third nitrogen spring 76 can be fixedly connected to the third pressure member 74 or detachably connected to it.

[0090] It is understandable that the pressing force provided by the first nitrogen spring 64, the second nitrogen spring 75, and the third nitrogen spring 76 is controllable, that is, the pressing force can be provided by the first nitrogen spring 64, the second nitrogen spring 75, and the third nitrogen spring 76 according to actual needs.

[0091] Nitrogen springs are elastic components that use high-pressure nitrogen gas as the working medium. They offer advantages such as small size, high elastic force, long stroke, smooth operation, long service life, a gentle elastic force curve, and no need for pre-tensioning. Therefore, nitrogen springs can simplify mold design and manufacturing, facilitate mold installation and adjustment, extend mold life, and ensure stable product quality.

[0092] Of course, at least one of the first nitrogen spring 64, the second nitrogen spring 75 and the third nitrogen spring 76 can be replaced by a metal spring, a rubber elastic element, a hydraulic support rod, etc.

[0093] Optionally, the second die 71 is provided with a recess 711 and the second punch 72 is provided with a protrusion 721. When the second die 71 and the second punch 72 are closed, the upper recess 711 and the protrusion 721 cooperate to form a storage bag 921 on the fourth plate surface 90.

[0094] The working process of the drawing die assembly is as follows:

[0095] (1) Drawing and forming by the first drawing die 60: The cross-section of the first drawing die 60 is as follows Figure 6 and Figure 7 As shown; the first die 61 moves downward with the slide block on the press and abuts against the first pressing member 63; the first nitrogen spring 64 provides pressing force to the first pressing member 63, the first pressing member 63 and the first die 61 cooperate to press the edge of the flat plate 80, and the flat plate 80 moves downward together with the first die 61; as the first die 61 and the first punch 62 move to close, the flat plate 80 is drawn to obtain the first plate surface 10 (AB section), the second plate surface 20 (BC section), the third plate surface 30 (IH section) and the first rounded corner 40 (CI section), completing the first process of drawing.

[0096] The radius R1 of the first fillet 40 obtained by the first drawing die 60 is greater than 20t1, which greatly reduces the contact stress between the first die 61 and the flat material 80, effectively eliminating the stamping marks generated during contact, making the stamping marks almost invisible to the naked eye.

[0097] (2) Drawing and forming using the second drawing die 70: The cross-section of the second drawing die 70 is as follows: Figure 8 and ​ As shown; the second die 71 moves downward with the slide on the press and abuts against the second pressing member 73 and the third pressing member 74; wherein, the second pressing member 73 cooperates with the second die 71 to press the first plate surface 10 and the second plate surface 20 (i.e., the ABC segment) to prevent material from flowing from the first plate surface 10 and the second plate surface 20; the third pressing member 74 cooperates with the second die 71 to press a portion of the third plate surface 30 to prevent wrinkling of the pressed portion of the third plate surface 30; then, the second pressing member 73, the third pressing member 74 and the second die 71 move downward together, and the protrusion 721 of the second punch 72 preferentially contacts the third plate surface 30, thereby pulling the material to flow along the C→H direction; to prevent wrinkling of the final forming surface CJDE segment, while excess material flows into the storage bag 921.

[0098] The clamping force at the second clamping member 73 is greater than that at the third clamping member 74. Optionally, the clamping force at the second clamping member 73 is the plate locking force, meaning that the material on the visible plate surface (segment ABC) does not flow due to locking, thus preventing stamping scratches from sliding into the visible plate surface; the clamping force at the third clamping member 74 is lower than the plate locking force, providing feasibility for material flow from H→I and avoiding cracking problems when the plate-shaped part is formed from CIH to CJDEFGH.

[0099] After the second drawing die 70 is completed, the second fillet 50 and fixed flange required by the product are obtained, and the risks of stamping marks flowing into the visible area and wrinkling of the flange surface are effectively avoided.

[0100] This application reduces contact stress by changing the size of the stamping contact radius and changes the material flow direction by setting a storage bag, thereby improving the appearance quality of sheet-like parts. This application does not modify the product's shape, redefine the product's visible area, or add additional product requirements; it also reduces post-processing, improves product manufacturing quality and efficiency, and lowers production costs.

[0101] The third aspect of this application discloses a plate-shaped part manufactured by the plate-shaped part forming method described in the first aspect. The plate-shaped part can be the inner C-pillar panel of a rear door window frame of an automobile, the outer panel of a water channel, etc.

[0102] The plate-shaped part adopts any one or more embodiments of the above-described plate-shaped part forming method, and therefore has the beneficial effects of the above-described embodiments, which will not be described in detail here.

[0103] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method of forming a sheet-like part, characterized by, The method comprises: adopting a first drawing die to draw the flat plate material to form a first plate surface, a second plate surface and a third plate surface in sequence, the first plate surface and the third plate surface are arranged in staggered manner, a first round corner is formed at the connecting position of the second plate surface and the third plate surface, and the radius of the first round corner is greater than 20t1, wherein t1 is the thickness of the flat plate material; adopting a second drawing die to draw the third plate surface in reverse to form a fourth plate surface, a storage bag is formed on the fourth plate surface, a second round corner is formed at the connecting position of the second plate surface and the fourth plate surface, and the radius of the second round corner is smaller than the radius of the first round corner.

2. The sheet part forming method according to Claim 1, wherein The radius of the first round corner is 12-30mm.

3. The sheet part forming method according to Claim 1, wherein The fourth plate surface comprises a first plate segment and a second plate segment, the connecting position of the second plate surface and the first plate segment forms the second round corner, the storage bag is located on the second plate segment, and the distance between the storage bag and the first plate segment is 3-12mm.

4. The sheet part forming method according to Claim 1, wherein The width of the storage bag is 3-12mm; and / or, the height of the storage bag is 3-12mm.

5. The sheet part forming method according to Claim 1, wherein The draft angle of the storage bag is 3°-12°.

6. The sheet part forming method according to any one of claims 1 to 5, characterized by, The storage bag protrudes towards the direction of reverse drawing.

7. A draw die assembly characterized by, The drawing die assembly is applied to the plate-shaped part forming method in any one of claims 1-6, the drawing die assembly comprises a first drawing die and a second drawing die, the first drawing die comprises a first die, a first punch and a first pressure piece, the first punch and the first pressure piece are both below the first die, the first die and the first pressure piece cooperate to press the edge of the flat plate material, and the first die and the first punch cooperate to form a first plate surface, a second plate surface, a third plate surface and a first round corner; the second drawing die comprises a second die, a second punch, a second pressure piece and a third pressure piece, the second punch, the second pressure piece and the third pressure piece are all below the second die, the second punch is between the second pressure piece and the third pressure piece, the second pressure piece and the second die cooperate to press the first plate surface and the second plate surface, the third pressure piece and the second die cooperate to press part of the third plate surface, and the second punch and the second die cooperate to draw another part of the third plate surface to form a second round corner and a fourth plate surface provided with a storage bag.

8. The draw die assembly of claim 7 wherein, The pressure force of the second pressure piece is greater than the pressure force of the third pressure piece.

9. The draw die assembly of claim 7 wherein, The drawing die assembly further comprises a first nitrogen gas spring connected with the first pressure piece to provide pressure force to the first pressure piece; and / or, the drawing die assembly further comprises a second nitrogen gas spring connected with the second pressure piece to provide pressure force to the second pressure piece; and / or, the drawing die assembly further comprises a third nitrogen gas spring connected with the third pressure piece to provide pressure force to the third pressure piece.

10. A sheet-like part, characterized by The plate-shaped part is made by the plate-shaped part forming method in any one of claims 1-6.

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