A stamping die for an automobile fuel tank shell part
By using a combination of drawing dies, blank holders, and nitrogen springs in the stamping dies for automotive fuel tank shell parts, the problems of wrinkles and uneven wall thickness in cylindrical and curved automotive fuel tank shell parts during processing are solved, achieving high-precision forming and simplified dies.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- DONGGUAN XUSHENG MOULD PROD CO LTD
- Filing Date
- 2025-08-04
- Publication Date
- 2026-07-07
AI Technical Summary
Existing technologies are prone to problems such as wrinkles, uneven wall thickness, and bottom cracking when processing automotive fuel tank shell parts with a certain depth in the middle and curved edges around the perimeter, and the molds are highly complex.
The system employs a combination structure of upper and lower dies, including a drawing die, a blank holder, a forming insert, and a nitrogen spring. By controlling the flow of the strip and the blank holder force, it achieves stable drawing and forming, reduces subsequent processes, and lowers the complexity of the mold.
It effectively avoids problems such as wrinkles and uneven wall thickness, improves processing accuracy and surface quality, simplifies mold structure, and reduces processing difficulty.
Smart Images
Figure CN224463545U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of stamping die technology, and in particular to a stamping die for an automotive fuel tank shell part. Background Technology
[0002] A car fuel tank is a container on a vehicle used to store fuel (such as gasoline or diesel) to supply fuel to the engine. The fuel tank is fitted with a shell component; some fuel tank shell components have a cylindrical structure with a certain depth in the middle and curved edges (e.g.,...). Figure 1 As shown, this type of part requires multiple stamping processes during processing, such as drawing, forming, and shaping. The drawing process transforms a flat blank into an open, hollow shape, or further modifies the shape and size of an open, hollow part. The forming process involves plastic deformation of the blank without breaking it, resulting in a specific shape and size. The shaping process further adjusts the precision and corrects the shape of the initially formed stamped part, ensuring it meets more accurate shape and size requirements and eliminating defects such as springback and deformation that may occur during stamping. In the drawing process, because these parts are thin and have a deep cylindrical structure, the blank is subjected to tangential compressive stress at the edges. If the material flows freely, it is prone to instability and wrinkling. Furthermore, if the speed and amount of the blank flowing into the die are not controlled during drawing, problems such as uneven wall thickness and bottom cracking may occur. Additionally, because these parts have curved edges and a complex structure, they require more subsequent stamping processes, increasing the complexity of the mold.
[0003] Therefore, it is necessary to provide a stamping die for automotive fuel tank shell parts with a cylindrical structure having a certain depth in the middle and curved edges around the perimeter. Utility Model Content
[0004] The technical problem to be solved by this utility model is to provide a stamping die for automotive fuel tank shell parts, which can be used for automotive fuel tank shell parts with a certain depth in the middle and curved surface structure around the edges.
[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0006] A stamping die for an automotive fuel tank housing part includes an upper die and a lower die. The upper die includes an upper die base on which a drawing die is fixed. The lower die includes a lower die base on which a drawing punch is provided that matches the drawing die. A pressure ring that can move up and down is provided around the outer periphery of the drawing punch. Several first nitrogen springs are provided below the pressure ring. The first nitrogen springs are mounted on the lower die base, and the piston rods of the first nitrogen springs are pressed against the bottom of the pressure ring. Several first forming inserts are fixed around the outer periphery of the drawing punch at the top of the pressure ring. The upper surface of each first forming insert is provided with a first forming surface that matches the periphery of the drawing die.
[0007] Furthermore, the two side walls of the pressure ring are provided with a first vertical positioning groove, and a first guide leg that matches the first vertical positioning groove is vertically fixed on the lower mold base. The outer side wall of the first guide leg is provided with a self-lubricating sliding plate for contacting the inner side wall of the first vertical positioning groove.
[0008] Furthermore, the upper die base is also provided with a forming die, which is located at the rear station of the drawing die, and a second forming insert is provided at one end of the forming die on the upper die base; a forming punch matching the forming die is provided on the lower die base, and a material support plate that can move up and down is provided at the bottom of the forming punch. The material support plate is fixedly connected to the bottom of the forming punch, and several second nitrogen springs are provided below the material support plate. The second nitrogen springs are installed on the lower die base, and the piston rod of the second nitrogen springs is pressed against the bottom of the material support plate. A third forming insert is fixed at one end of the forming punch on the lower die base, and the upper surface of the third forming insert is provided with a second forming curved surface that matches the lower surface of the second forming insert.
[0009] Furthermore, the two side walls of the material support plate are provided with second vertical positioning grooves, and the lower mold base is vertically fixed with second guide legs that match the second vertical positioning grooves. The outer side wall of the second guide legs is provided with a self-lubricating sliding plate for contacting the inner side wall of the second vertical positioning groove.
[0010] Furthermore, a forming die is fixed on the upper die base, which is located at the rear station of the forming die, and a fourth forming insert is provided at one end of the forming die on the upper die base; a forming punch that matches the forming die is fixed on the lower die base, and a fifth forming insert is fixed at one end of the forming punch on the lower die base, and the upper surface of the fifth forming insert is provided with a third forming surface that matches the lower surface of the fourth forming insert.
[0011] Furthermore, the upper mold base has a third guide leg fixed vertically on both sides; the lower mold base has guide openings on both sides that match the third guide leg, a guide leg seat is fixed at the top of the guide opening, a guide groove is vertically opened on the guide leg seat that communicates with the guide opening, and a self-lubricating sliding plate is provided on the inner side wall of the guide groove for contacting the outer side wall of the third guide leg.
[0012] Furthermore, multiple guide rulers are provided on both sides of the material strip on the lower die base, and the multiple guide rulers are spaced apart along the conveying direction of the material strip.
[0013] Compared with the prior art, this utility model achieves at least the following beneficial effects:
[0014] 1. In the drawing process, when the upper and lower dies close, the upper die holder moves downward with the drawing die. The drawing die first presses the strip onto the upper surface of the first forming insert. The first forming insert and the blank holder, due to the elastic force of the first spring, can also apply appropriate blank holder force to the edge of the strip, keeping the strip in a stable position. As the upper die holder continues to move downward, the drawing punch begins to draw the strip. During the drawing process, wrinkles caused by excessive flow of the strip can be avoided. Furthermore, by adjusting the blank holder force of the first forming insert and the blank holder, the speed and amount of the strip flowing into the drawing die can be controlled, avoiding problems such as uneven wall thickness and bottom cracking of the parts. When the upper and lower dies open, the upper die holder moves upward with the drawing die. The first forming insert and the blank holder, under the elastic force of the first nitrogen spring, push upward to unload the drawn parts from the working surface of the die.
[0015] 2. By arranging multiple first forming inserts around the drawing punch, these inserts can serve as supplementary structures to the drawing punch, simultaneously forming the curved surfaces and other structures around the edges of the part during the drawing process. This reduces subsequent processes and lowers the complexity of the die. The insert design makes it easy to adjust, modify, or replace the first forming inserts in specific areas without affecting other parts. Compared to an integral drawing punch, the combined structure of multiple first forming inserts and the drawing punch has a relatively simple shape and structure for each first forming insert, making it easier to perform machining, electrical discharge machining, and other processes, thereby improving machining accuracy and surface quality. Attached Figure Description
[0016] Figure 1 This is a structural schematic diagram of a prior art automotive fuel tank shell component;
[0017] Figure 2 This is a schematic diagram of the structure of an embodiment of this application;
[0018] Figure 3 This is a schematic diagram of the upper mold base according to an embodiment of this application;
[0019] Figure 4 This is a schematic diagram of the structure of the lower mold base according to an embodiment of this application;
[0020] Figure 5 This is a schematic diagram of the pressure ring and material support plate in an embodiment of this application.
[0021] The numbers in the diagram are as follows: 1. Upper die holder; 2. Lower die holder; 3. Drawing die; 4. Drawing punch; 5. Blank holder ring; 51. First vertical positioning groove; 6. First nitrogen spring; 7. First forming insert; 71. First forming surface; 8. First guide leg; 9. Forming die; 10. Second forming insert; 20. Forming punch; 30. Material support plate; 301. Second vertical positioning groove; 40. Second nitrogen spring; 50. Third forming insert; 501. Second forming surface; 60. Second guide leg; 70. Shaping die; 80. Fourth forming insert; 90. Shaping punch; 100. Fifth forming insert; 1001. Third forming surface; 200. Third guide leg; 300. Guide opening; 400. Guide leg seat; 500. Guide ruler; 600. Self-lubricating slide plate; 700. Material strip; 800. Automobile fuel tank shell part. Detailed Implementation
[0022] The present invention will now be described in detail with reference to exemplary embodiments shown in the accompanying drawings. However, it should be understood that the present application may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided herein to make the disclosure of this application more complete and to fully convey the concept of the present application to those skilled in the art.
[0023] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "several" or "more than" means two or more, unless otherwise explicitly specified. In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. In this application, unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or it can include contact between the first and second features through another feature between them. Moreover, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0024] like Figures 2-5 As shown in the figure, the stamping die for an automotive fuel tank housing part provided in this application embodiment includes an upper die and a lower die, which is designed for... Figure 1 The shown is used in automotive fuel tank housing part 800, which has a cylindrical structure with a certain depth and curved edges on all four sides.
[0025] The upper die includes an upper die base 1, on which a drawing die 3 is fixed; the lower die includes a lower die base 2, on which a drawing punch 4 that matches the drawing die 3 is provided. A pressure ring 5 that can move up and down is provided around the outer periphery of the drawing punch 4. Several first nitrogen springs 6 are provided below the pressure ring 5. The first nitrogen springs 6 are installed on the lower die base 2, and the piston rod of the first nitrogen spring 6 is pressed against the bottom of the pressure ring 5. Several first forming inserts 7 are fixed around the outer periphery of the drawing punch 4 at the top of the pressure ring 5. The upper surface of each first forming insert 7 is provided with a first forming surface 71 that matches the periphery of the drawing die 3.
[0026] Before the upper and lower dies close, the first forming insert 7 and the blank holder 5 are pushed upwards by the elastic force of the first nitrogen spring 6. When the upper and lower dies close, the upper die holder 1 moves downwards with the drawing die 3. The drawing die 3 first presses the strip 700 onto the upper surface of the first forming insert 7, while the first forming insert 7 and the blank holder 5 can also apply appropriate blank holder force to the strip 700 due to the elastic force of the first spring, keeping the strip 700 in a stable position. As the upper die holder 1 continues to move downwards, the drawing punch 4 begins to press the strip 700... During the drawing process, wrinkles can be prevented from forming due to excessive flow of the strip 700. By adjusting the blanking force of the first forming insert 7 and the blanking ring 5, the speed and amount of the strip flowing into the drawing die 3 can be controlled, avoiding problems such as uneven wall thickness and bottom cracking of the parts. When the upper and lower dies open, the upper die holder 1 moves the drawing die 3 upward with it. The first forming insert 7 and the blanking ring 5 are pushed upward under the elastic force of the first nitrogen spring 6 to unload the drawn parts from the working surface of the die, preventing the parts from getting stuck in the die. It should be noted that by arranging multiple first forming inserts 7 around the drawing punch 4, these inserts can serve as supplementary structures to the drawing punch 4. During the drawing process, they simultaneously complete the forming of the curved surfaces and other structures around the edges of the stamped parts, reducing subsequent processes and lowering the complexity of the mold. The first forming inserts 7 can be made of wear-resistant hard alloy material, capable of withstanding local high stress (such as at corners), reducing wear on the main body of the drawing punch 4. Moreover, the insert design makes it easy to adjust, modify, or replace the first forming inserts 7 in corresponding parts without affecting other parts, facilitating maintenance or adjustment. Furthermore, the combined structure of multiple first forming inserts 7 and the drawing punch 4 is easier to process and manufacture than the integral drawing punch 4. The shape and structure of each first forming insert 7 are relatively simple, making it easier to perform machining, electrical discharge machining, and other processes, thereby improving machining accuracy and surface quality.
[0027] In this embodiment, the pressure ring 5 has first vertical positioning grooves 51 on both side walls, and a first guide leg 8 that matches the first vertical positioning groove 51 is vertically fixed on the lower mold base 2. The outer side wall of the first guide leg 8 has a self-lubricating sliding plate 600 for contacting the inner side wall of the first vertical positioning groove 51. The first vertical positioning groove 51 of the pressure ring 5 cooperates with the self-lubricating sliding plate 600 of the first guide leg 8 to achieve precision guidance.
[0028] In this embodiment, the upper die base 1 is also provided with a forming die 9, which is located at the rear station of the drawing die 3, and a second forming insert 10 is provided at one end of the forming die 9 on the upper die base 1; a forming punch 20 matching the forming die 9 is provided on the lower die base 2, and a material support plate 30 that can move up and down is provided at the bottom of the forming punch 20. The material support plate 30 is fixedly connected to the bottom of the forming punch 20, and a plurality of second nitrogen springs 40 are provided below the material support plate 30. The second nitrogen springs 40 are installed on the lower die base 2, and the piston rod of the second nitrogen springs 40 is pressed against the bottom of the material support plate 30. A third forming insert 50 is fixed at one end of the forming punch 20 on the lower die base 2, and a second forming curved surface 501 matching the lower surface of the second forming insert 10 is provided on the upper surface of the third forming insert 50.
[0029] Similarly, before the upper and lower molds close, the support plate 30 is pushed upwards by the elastic force of the second nitrogen spring 40. When the upper and lower molds close, the upper mold base 1 moves downwards with the forming die 9. The forming die 9 first presses the part onto the upper surface of the forming punch 20. Due to the elastic force of the second nitrogen spring 40, the forming punch 20 and the support plate 30 can also apply appropriate blank holder force to the part, keeping the part in a stable position. As the upper mold base 1 continues to move downwards, the second forming insert and the third forming insert 50 cooperate to further form the part. In this embodiment, the curved surface structure on the left side of the part is formed, and the part can be prevented from shifting during the forming process, ensuring the machining accuracy of the part. The combination design of the second forming insert and the forming punch 20, and the combination design of the third forming insert 50 and the forming die 9, make maintenance or adjustment easier, and make processing and manufacturing easier.
[0030] The material support plate 30 has second vertical positioning grooves 301 on both side walls. A second guide leg 60, matching the second vertical positioning groove 301, is vertically fixed on the lower mold base 2. The outer side wall of the second guide leg 60 has a self-lubricating sliding plate 600 for contacting the inner side wall of the second vertical positioning groove 301. The second vertical positioning groove 301 of the material support plate 30 cooperates with the self-lubricating sliding plate 600 of the second guide leg 60 to achieve precision guidance.
[0031] In this embodiment, a forming die 70 is also fixed on the upper die base 1. The forming die 70 is located at the rear station of the forming die 9, and a fourth forming insert 80 is provided at one end of the forming die 70 on the upper die base 1. A forming punch 90 matching the forming die 70 is fixed on the lower die base 2, and a fifth forming insert 100 is fixed at one end of the forming punch 90 on the lower die base 2. The upper surface of the fifth forming insert 100 is provided with a third forming curved surface 1001 matching the lower surface of the fourth forming insert 80. When the upper and lower dies are closed, the forming punch 90 and the forming die 70 cooperate to further trim and refine the pre-processed parts, thereby improving the dimensional accuracy and surface quality of the parts and reducing the springback of the parts. The fourth forming insert and the fifth forming insert 100 cooperate to perform further forming processing on the parts. In this embodiment, the curved surface structure on the right side of the parts is formed.
[0032] In this embodiment, third guide legs 200 are vertically fixed on both sides of the upper mold base 1; guide openings 300 matching the third guide legs 200 are vertically provided on both sides of the lower mold base 2. A guide leg seat 400 is fixed to the top of the guide opening 300. A guide groove communicating with the guide opening 300 is vertically opened on the guide leg seat 400. A self-lubricating sliding plate 600 for contacting the outer side wall of the third guide leg 200 is provided on the inner side wall of the guide groove. The third guide leg 200 is inserted into the guide leg seat 400, which can ensure that the upper and lower molds are strictly aligned when the molds are closed, avoid the punch and die from skewed collision, and prevent the mold from shaking during high-speed stamping.
[0033] In this embodiment, multiple guide rulers 500 are provided on both sides of the material strip 700 on the lower die base 2, and the multiple guide rulers 500 are spaced apart along the conveying direction of the material strip 700. The guide rulers 500 are provided on both sides of the material strip 700 to provide precise guidance for the feeding of the material strip 700 in the die, ensuring that the material strip 700 moves accurately in a predetermined direction, so that the stamping process at each station can be carried out accurately, and ensuring the dimensional accuracy and positional accuracy of the stamped parts.
[0034] It should be understood that all the above embodiments are exemplary and not restrictive. Any modifications, equivalent changes and alterations made by those skilled in the art to the specific embodiments described above under the concept of this utility model shall still fall within the scope of the technical solution of this utility model.
Claims
1. A stamping die for an automotive fuel tank shell part, comprising an upper die and a lower die, characterized in that: The upper die includes an upper die base, on which a drawing die is fixed; The lower die includes a lower die base, on which a drawing punch is provided that matches the drawing die. A pressure ring that can move up and down is provided around the outer periphery of the drawing punch. Several first nitrogen springs are provided below the pressure ring. The first nitrogen springs are mounted on the lower die base, and the piston rods of the first nitrogen springs are abutted against the bottom of the pressure ring. Several first forming inserts are fixed around the top of the pressure ring on the outer periphery of the drawing punch. The upper surface of each first forming insert is provided with a first forming curved surface that matches the periphery of the drawing die.
2. The stamping die for the automotive fuel tank shell part according to claim 1, characterized in that: The pressure ring has a first vertical positioning groove on both sides of its sidewalls. The lower mold base has a first guide leg that matches the first vertical positioning groove. The outer sidewall of the first guide leg has a self-lubricating sliding plate for contacting the inner sidewall of the first vertical positioning groove.
3. The stamping die for the automotive fuel tank shell part according to claim 1, characterized in that: The upper die base is also provided with a forming die, which is located at the rear station of the drawing die. A second forming insert is provided at one end of the forming die on the upper die base. A forming punch matching the forming die is provided on the lower die base. A material support plate that can move up and down is provided at the bottom of the forming punch. The material support plate is fixedly connected to the bottom of the forming punch. Several second nitrogen springs are provided below the material support plate. The second nitrogen springs are installed on the lower die base, and the piston rods of the second nitrogen springs are pressed against the bottom of the material support plate. A third forming insert is fixed at one end of the forming punch on the lower die base. The upper surface of the third forming insert is provided with a second forming curved surface that matches the lower surface of the second forming insert.
4. The stamping die for the automotive fuel tank shell part according to claim 3, characterized in that: The material support plate has a second vertical positioning groove on both sides. The lower mold base has a second guide leg that matches the second vertical positioning groove. The outer side wall of the second guide leg has a self-lubricating sliding plate for contacting the inner side wall of the second vertical positioning groove.
5. The stamping die for the automotive fuel tank shell part according to claim 3, characterized in that: The upper mold base is also fixed with a forming die, which is located at the rear station of the forming die, and a fourth forming insert is provided at one end of the forming die on the upper mold base; a forming punch that matches the forming die is fixed on the lower mold base, and a fifth forming insert is fixed at one end of the forming punch on the lower mold base, and the upper surface of the fifth forming insert is provided with a third forming surface that matches the lower surface of the fourth forming insert.
6. The stamping die for the automotive fuel tank shell part according to claim 1, characterized in that: The upper mold base has a third guide leg fixed vertically on both sides; the lower mold base has guide openings on both sides that match the third guide leg, a guide leg seat is fixed at the top of the guide opening, a guide groove is vertically opened on the guide leg seat that communicates with the guide opening, and a self-lubricating slide plate is provided on the inner side wall of the guide groove for contacting the outer side wall of the third guide leg.
7. The stamping die for the automotive fuel tank shell part according to claim 1, characterized in that: The lower die base is provided with multiple guide rulers on both sides of the material strip, and the multiple guide rulers are spaced apart along the conveying direction of the material strip.