Composite drawing die
By using a composite drawing die to achieve pre-forming and drawing on a single die, the problem of material flow difficulties in deep products is solved, achieving efficient forming and quality assurance.
Patent Information
- Application Number
- CN202520188587.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-07
- Publication Date
- 2026-01-02
- Estimated Expiration
- 2035-02-07
AI Technical Summary
Existing technologies, when used for products with large forming depths, result in a small cavity width-to-height ratio, making material flow difficult. This leads to excessive sheet thinning or cracking, and requires multiple sets of molds and multiple stamping processes.
By employing a composite drawing die, two stamping actions, pre-forming and drawing, are achieved on a single die. The relative position adjustment between the blank holder and the punch, along with the cooperation of a nitrogen spring, optimizes material flow and prevents excessive thinning and cracking.
It enables the smooth forming of deep products on a single mold, reducing mold investment costs, improving production efficiency, and ensuring product quality and mechanical strength.
Smart Images
Figure CN223748336U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to sheet metal stamping forming technical field, specifically a kind of composite draw die for the drawing product forming of cavity width-height ratio small, and top easy thinning cracking. BACKGROUND
[0002] For the product of more complex shape, stamping process mainly includes drawing, trimming, punching, flanging, shaping and other processes. But some product forming depth is large, when taking one drawing process, cavity width-height ratio is small, material flow is difficult, which will cause product top thinning rate to be out of tolerance, even cracking defect appears. For the product of larger depth and unable to draw forming once, traditional scheme is to take multiple drawing process, or preforming and drawing combined process, need to invest multiple sets of die, after multiple stamping processes, qualified product can be produced. SUMMARY
[0003] To overcome the deficiencies of prior art, the application aims to provide a kind of composite draw die, can realize preforming and drawing two stamping forming actions simultaneously on a set of die, to solve the problem of sheet metal thinning out of tolerance or cracking caused by the product of large forming depth due to unsmooth flow.
[0004] To realize the above-mentioned application purposes, the guide pillar of the composite draw die of the utility model is installed on the lower die seat, the guide sleeve is installed on the upper die seat, the concave die is installed and fixed on the upper die seat through the first bolt and the positioning pin, the convex die is installed on the lower die seat through the second bolt and the positioning pin one, the nitrogen spring is installed on the lower die seat through the third bolt, and acts on the lower surface of the blank holder ring, the blank holder ring is sleeved on the convex die, the limiting bolt is installed on the lower die seat and passes through the lower die seat, and the blank holder ring is fixed through the limiting bolt.
[0005] Further, the upper surface of the initial position of the blank holder ring is lower than the upper surface of the convex die by a height difference h; the inner cavity of the blank holder ring is in sliding fit with the convex die.
[0006] Further, the guide pillars are uniformly distributed and installed at four corners of the lower die seat; the guide sleeves are uniformly distributed and installed at four corners of the upper die seat; the guide pillars and the guide sleeves are in sliding fit.
[0007] Further, the first bolts and the positioning pins are uniformly distributed and installed at four corners of the upper die seat and the concave die.
[0008] Further, the positioning block is installed on one side of the upper part of the blank holder ring, and protrudes from the upper surface of the blank holder ring.
[0009] Further, the limiting bolts are uniformly distributed and installed at four corners of the blank holder ring and the lower die seat.
[0010] Further, the second bolt and the positioning pin are four groups, and are evenly arranged on the lower die seat and the male die.
[0011] Further, the nitrogen gas springs are evenly arranged at four corners of the lower die seat.
[0012] To solve the problem of sheet thinning and cracking, the initial position of the blank holder is lowered, and the upper surface of the blank holder is lower than the upper surface of the male die by a certain distance. The sheet is positioned on the male die by the positioning block, the female die is driven downward by the upper die seat, the female die starts to contact the sheet, and the sheet around the female die and the male die flows freely to the middle to be formed. In this process, the sheet around is not compressed and flows freely to the female die, and the sheet is not thinned in the contact area with the male die, and this process is preforming. The upper die seat continues to move downward, the sheet contacts the blank holder, the blank holder is compressed together with the female die under the action of the nitrogen gas spring, and the sheet is compressed in the contact area with the blank holder; the upper die seat continues to move downward, and the sheet continues to deform under the combined action of the female die, the male die, and the friction force of the contact area between the sheet and the blank holder, until the female die surface and the male die surface are completely attached to the upper and lower surfaces of the sheet, and the drawing process is completed.
[0013] The CAE simulation and repeated analysis can minimize the thinning of the contact area between the sheet and the top of the male die, and ensure that the sheet does not wrinkle during preforming, so that the height difference between the upper surface of the blank holder and the upper surface of the male die is reasonable. Because part of the sheet has flowed into the female die cavity after preforming, the blank holder force of the drawing process can be re-adjusted by the CAE analysis result, and different types of nitrogen gas springs are replaced, so that the sheet flows smoothly during the drawing process.
[0014] Compared with the prior art, the initial relative position of the blank holder and the male die can be adjusted to ensure the flow of the material during preforming, and the resistance of the material flow during the drawing process is optimized, so that the local area thickness of the sheet is not thinned, the local strength of the stamping product is avoided, the mechanical strength and use performance of the stamping part can be effectively ensured, the structure is simple, the mold investment cost can be effectively reduced, the production efficiency is improved, the product quality is ensured, and the drawing forming product with small cavity width-height ratio and easy thinning and cracking at the top is suitable. BRIEF DESCRIPTION OF DRAWINGS
[0015] In order to make the content of the utility model more easily and clearly understood, the utility model will be further described in detail below according to specific embodiments and in combination with the drawings, wherein:
[0016] Figure 1 It is a structural diagram of the utility model.
[0017] Figure 2 It is Figure 1 a mold closed state diagram.
[0018] In the diagram: 1. Lower mold base; 2. Guide pillar; 3. Limiting bolt; 4. Pressure ring; 5. Guide sleeve; 6. Upper mold base; 7. First bolt; 8. Locating pin; 9. Punch; 10. Die; 11. Sheet metal; 12. Locating block; 13. Second bolt; 14. Locating pin one; 15. Nitrogen spring; 16. Third bolt. Detailed Implementation
[0019] To make the utility model's objectives, technical solutions, and advantages clearer, the following detailed description, in conjunction with embodiments, further illustrates the utility model. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of protection of the utility model.
[0020] like Figure 1 , Figure 2 As shown, the guide pillars 2 of the composite drawing die of this utility model are installed on the lower die base 1, and the guide sleeves 5 are installed on the upper die base 6. The guide pillars 2 are evenly distributed at the four corners of the lower die base 1, and the guide sleeves 5 are evenly distributed at the four corners of the upper die base 6. The guide pillars 2 and guide sleeves 5 are in sliding fit. The die cavity 10 is fixed to the upper die base 6 by the first bolt 7 and the positioning pin 8. The first bolt 7 and the positioning pin 8 are evenly distributed at the four corners of the upper die base 6 and the die cavity 10. The punch 9 is installed on the lower die base 1 by the second bolt 13 and the positioning pin 14. The second bolt 13 and the positioning pin 14 are in four sets and are evenly distributed on the lower die base 1 and the punch 9. The nitrogen spring 15 is installed on the lower die base 1 by the third bolt 16 and acts on the lower surface of the blank holder 4. Nitrogen springs 15 are evenly distributed and installed at the four corners of the lower die base 1; the pressure ring 4 is sleeved on the punch 9, and the limiting bolt 3 passes through the lower die base 1 and is installed on the lower die base 1. The pressure ring 4 is fixed by the limiting bolt 3. The limiting bolt 3 is evenly distributed and installed at the four corners of the pressure ring 4 and the lower die base 1. The height difference h between the upper surface of the initial position of the pressure ring 4 and the upper surface of the punch 9 is lower than that of the punch 9. That is, the height difference h between the upper surface of the initial position of the pressure ring 4 and the upper surface of the punch 9 is 20-22mm. The inner cavity of the pressure ring 4 slides with the punch 9; the positioning block 12 is installed on the pressure ring 4. The positioning block 12 is installed on the upper part of the pressure ring 4 and located on one side of the sheet metal 11. The sheet metal 11 is positioned on the punch 9 by the positioning block 12 and protrudes from the upper surface of the pressure ring 4.
[0021] The sheet metal 11 is positioned on the male die 9 by the positioning block 12, the upper die seat 6 drives the female die 10 to move downwards, the female die 10 starts to contact the sheet metal 11, and the sheet metal 11 flows freely to the middle under the action of the female die 10 and the male die 9. In this process, the sheet metal 11 is not compressed around, and flows freely to the female die 10, and the area of the sheet metal 11 contacting the male die 9 is basically not thinned, and this process is preforming. The upper die seat 6 continues to move downwards, the sheet metal 11 contacts the blank holder 4, the blank holder 4 is compressed with the female die 10 to compress the area of the sheet metal 11 contacting the blank holder 4 under the action of the nitrogen spring 15. The upper die seat 6 continues to move downwards, and the sheet metal 11 continues to deform under the combined action of the female die 10, the male die 9 and the friction force of the area of the sheet metal 11 contacting the blank holder 4, until the lower surface of the female die 10 and the upper surface of the male die 9 are completely attached to the upper and lower surfaces of the sheet metal 11, and the drawing process is completed.
[0022] The reasonable height difference h between the upper surface of the initial position of the blank holder 4 and the upper surface of the male die 9 is obtained through computer CAE simulation analysis, and at the same time, it can be ensured that there is no wrinkling phenomenon in the preforming process of the sheet metal 11, and the minimum top thinning amount. The blank holder force required for the sheet metal 11 after preforming and then drawing can be determined through simulation analysis, so as to select a suitable nitrogen spring 15, ensure that the friction force of the sheet metal 11 flowing in the female die 10 and the blank holder 4 is moderate, smoothly complete the drawing action of the sheet metal 11, and finally ensure that the product thinning is not out of tolerance.
[0023] The basic principle, main features and advantages of the utility model are shown and described above. It should be understood by those skilled in the art that the utility model is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principle of the utility model, and various changes and improvements can be made without departing from the spirit and scope of the utility model, and these changes and improvements all fall within the scope of the utility model claimed. The protection scope of the utility model is defined by the appended claims and their equivalents.
Claims
1. A composite draw die characterized by: The guide pillar (2) is installed on the lower die seat (1), the guide sleeve (5) is installed on the upper die seat (6), the concave die (10) is installed and fixed on the upper die seat (6) through the first bolt (7) and the positioning pin (8), the convex die (9) is installed on the lower die seat (1) through the second bolt (13) and the positioning pin (14), the nitrogen spring (15) is installed on the lower die seat (1) through the third bolt (16) and acts on the lower surface of the blank holder (4), the blank holder (4) is sleeved on the convex die (9), the limiting bolt (3) is installed on the lower die seat (1) through the lower die seat (1), and the blank holder (4) is fixed through the limiting bolt (3); the positioning block (12) is installed on the blank holder (4) and located on one side of the sheet metal (11), and the sheet metal (11) is positioned on the convex die (9) through the positioning block (12).
2. A composite drawing die according to claim 1, wherein: The height difference of the upper surface of the initial position of the blank holder (4) is lower than that of the upper surface of the convex die (9) by h; the inner cavity of the blank holder (4) is in sliding fit with the convex die (9).
3. A composite drawing die according to claim 1, wherein: The guide pillars (2) are uniformly installed at the four corners of the lower die seat (1); the guide sleeves (5) are uniformly installed at the four corners of the upper die seat (6); the guide pillars (2) are in sliding fit with the guide sleeves (5).
4. A composite drawing die according to claim 1, wherein: The first bolts (7) and the positioning pins (8) are uniformly installed at the four corners of the upper die seat (6) and the concave die (10).
5. A composite drawing die according to claim 1 wherein: The positioning block (12) is installed on one side of the upper part of the blank holder (4) and protrudes from the upper surface of the blank holder (4).
6. A composite drawing die according to claim 1 wherein: The limiting bolts (3) are uniformly installed at the four corners of the blank holder (4) and the lower die seat (1).
7. A composite drawing die according to claim 1 wherein: The second bolts (13) and the positioning pins (14) are four groups and are uniformly installed on the lower die seat (1) and the convex die (9).
8. A composite drawing die according to claim 1 wherein: The nitrogen springs (15) are uniformly installed at the four corners of the lower die seat (1).