CN113926917B - A drawing and trimming composite mold for automobile front floor and its processing method - Google Patents

Abstract

The invention discloses a drawing and trimming composite mold for automobile front floor and a processing method thereof, which includes a drawing die and a drawing punch arranged up and down, and a blanking ring is provided in the drawing punch; The drawing die and the drawing punch are respectively provided with corresponding trimming die and trimming punch for trimming the four corners of the sheet. The trimming punch is located at In the edge holder ring, a through hole is provided on the edge holder ring for the top of the trimming punch to pass through. By integrating the trimming mold into the drawing mold, the processing steps are reduced and the structural defects of the front floor trimming and flanging composite mold itself are solved. The parts are less likely to produce chips and burrs, have high quality and robustness, and have low mold processing and debugging requirements. , the mold mass production status in the later period was stable, and the quality of parts was effectively guaranteed. Compared with the three-process front floor process, the development of a set of stamping molds is reduced and the manufacturing cost of a set of molds is saved.

Description

A drawing and trimming composite mold for automobile front floor and its processing method

Technical field

The invention relates to the technical field of automobile manufacturing, and specifically refers to a drawing and trimming composite mold for automobile front floor and its processing method.

Background technique

In recent years, as the Chinese automobile market has entered negative growth, the survival of the fittest among automobile manufacturers has accelerated. In order to seize the initiative in the increasingly severe competitive environment, major automobile manufacturers have continued to innovate in the development stage of new models and promoted new processes and new technologies in production. application, thereby reducing new model investment and single vehicle production costs. At present, automobile panel parts are mainly produced using the stamping forming process. Stamping usually requires two processes or a combination of multiple processes to complete the production of parts. In the production cost of automotive stamping parts, the cost of mold development and the cost of press machine use account for a relatively high ratio to the total cost of parts. Therefore, reducing the number of parts molding processes and reducing mold development costs and press usage costs is one of the important ways for automobile manufacturers to reduce vehicle costs. As one of the interior covering parts of the car, the front floor has its own characteristics: first, the overall shape of the part is shallow, so the amount of material inflow during the molding process is small; second: as an interior covering part of the car, the appearance quality is required relatively low. Due to the small inflow of front floor material and relatively low quality requirements, the front floor parts can be compounded in the mold structure process on the basis of meeting the quality requirements to reduce vehicle production costs. In order to reduce the number of front floor stamping mold processes, domestic engineers have conducted in-depth research on the stamping process and mold structure design of the front floor. Dong Liguang et al. designed a trimming and flanging composite mold based on the OP20 process of trimming and flanging, which satisfies the two-step stamping process plan for the front floor (Dong Liguang, Gao Yuan, Gu Xiaoyu, etc.). Automobile front floor trimming and flanging composite mold Design[J]. Mold Industry 2013, 02-0033-03). However, its composite mold structure only stays at the trimming and flanging composite mold in the OP20 process. Due to its structural defects, the parts are prone to chips and burrs during trimming, and the quality is poor. At the same time, this composite mold Molds have extremely high requirements for mold processing and debugging. The mass production of molds in the later stage is extremely unstable, and it is difficult to effectively guarantee the quality of parts.

Contents of the invention

The purpose of the present invention is to solve the above deficiencies in the background technology and provide a composite drawing and trimming mold for automobile front floor that combines the drawing and trimming processes to ensure stable trimming quality and a processing method thereof.

In order to achieve this goal, the composite mold for drawing and trimming of the automobile front floor designed by the present invention includes a drawing die and a drawing punch arranged up and down, and a blanking ring is provided in the drawing punch; its characteristics The method is: the drawing die and the drawing punch are respectively provided with trimming die and trimming convex molds corresponding to each other and used for trimming the four corners of the sheet material, and the trimming die The edge punch is located in the edge holder ring, and the edge holder ring is provided with a through hole for the top of the trimming punch to pass through.

Further, the drawing die is provided with one trimming die corresponding to the trimming positions at the four corners of the sheet material; the drawing punch is located at the four corners of the sheet material. One of the trimming punches is respectively provided at the trimming corresponding position of each corner.

Further, the blank holder includes a central blank holder located in the middle of the drawing punch for compressing the middle surface of the sheet material and a central blank holder located outside the drawing punch for compressing the sheet. The outer edge ring of the outer surface of the sheet material, the trimming punch is arranged between the middle edge ring and the outer edge ring.

Further, a mold blade is provided below the outer edge holder for pushing the outer edge holder and the drawing die, and avoiding the die edge of the drawing die from the drawing punch. Oral contact push structure.

Further, the pushing structure includes four pushing cylinders respectively disposed below the four corners of the outer edge holder, and the piston rods of the thrust cylinders are connected to the bottom of the outer edge holder.

Further, the drawing die and the drawing punch are respectively provided with guide structures that cooperate with each other and are used to accurately match the trimming die with the trimming punch.

Further, the guide structure includes four guide sleeves fixed in the drawing die and located at four corners of the drawing die and four guide sleeves fixed in the drawing punch and located at the drawing die. The guide pillars at the four corners of the punch.

The processing method of the drawing and trimming composite mold based on the above-mentioned automobile front floor is: placing the sheet, the drawing die moves down, the drawing die and the edge holder cooperate to press the middle surface of the sheet, the drawing die and The drawing punch cooperates with the drawing operation of the sheet. The drawing die continues to move downward. The drawing die and the edge holder cooperate to press the outer surface of the sheet. The trimming die and the trimming punch cooperate with the sheet. Trim the edges at the four corners, move the drawing die upward, and take out the sheet.

Further, the trimming die and the trimming punch cooperate to trim the four corners of the sheet. The trimming punch uses a trimming knife with a beveled top surface. The edge concave mold adopts a trimming sleeve with an axis hole that matches the trimming knife, and the top part of the trimming knife is bladed into the sheet material and enters the trimming sleeve.

Furthermore, the height of the trimming blade into the sheet material is 0.8mm-1.2mm.

The beneficial effects of the present invention are: by integrating the trimming mold on the drawing mold, the processing steps are reduced, the structural defects of the front floor trimming and flanging composite mold itself are solved, the parts are less likely to produce chips and burrs, and the quality is high and robust. , the requirements for mold processing and debugging are low, the mass production of molds in the later stage is stable, and the quality of parts is effectively guaranteed. Compared with the three-step front floor process, the development of a set of stamping molds is reduced and the manufacturing cost of a set of molds is saved.

Description of drawings

Figure 1 is a vertical cross-sectional view of the sheet material processed by the drawing and trimming composite mold of the automobile front floor in the present invention;

Figure 2 is an enlarged view of i1 in Figure 1;

Figure 3 is an enlarged view of i2 in Figure 1;

Figure 4 is a layout diagram of the stamping process of sheet metal in the present invention;

Figure 5 is an enlarged view of point a in Figure 4;

Figure 6 is a dimensional view of the four corners trimmed in the present invention;

Figure 7 is a cross-sectional view of A-A in Figure 6;

Among them, 1 - drawing die, 2 - drawing punch, 3 - blanking ring (3.1 - middle blanking ring, 3.2 - outer blanking ring), 4 - sheet material, 5 - trimming die, 6 - Trimming punch, 7 - push cylinder, 8 - guide sleeve, 9 - guide column, 10 - sheet material line, 11 - parting line, 12 - four corner trimming line, 13 - flanging contour line, 14 - intersection Knife point, 15 - drawing and trimming line.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The drawing and trimming composite mold shown in Figures 1-7 includes a drawing die 1 and a drawing punch 2 arranged up and down. The drawing punch 2 is provided with a blank holder 3; the drawing die 1 and The drawing punch 2 is respectively provided with corresponding trimming die 5 and trimming punch 6 for trimming the four corners of the sheet 4. The trimming punch 6 is located in the edge ring 3 Inside, the edge holder ring 3 is provided with a through hole for the top of the trimming punch 6 to pass through. The blank holder ring 3 includes a middle blank holder ring 3.1 located in the middle of the drawing punch 2 for compressing the middle surface of the sheet material 4 and an outer side located outside the drawing punch 2 for compressing the outer surface of the sheet material 4. The edge holder ring 3.2 and the trimming punch 6 are arranged between the middle edge holder ring 3.1 and the outer edge holder ring 3.2. A push structure is provided below the outer blank holder 3.2, which includes four push cylinders 7 respectively disposed below the four corners of the outer blank holder 3.2. The piston rods of the push cylinders 7 are connected to the piston rods of the outer blank holder 3.2. bottom.

The drawing die 1 and the drawing punch 2 are respectively provided with guide structures that cooperate with each other and are used to accurately match the trimming die 5 and the trimming punch 6, which include guide structures fixed in the drawing die 1 and located at There are four guide sleeves 8 at the four corners of the drawing die 1 and guide posts 9 fixed in the drawing punch 2 and located at the four corners of the drawing punch 2 .

Stamping process design:

In order to ensure the strength of the mold, the details of the trimming contour process dimensions are shown in Figure 6, which must meet the following design: Based on the tangent point of the flanging radius R of the flanging contour line 13 of the part and the four-corner trimming line 12, extend the length b inward , b size is 25mm, the purpose is to ensure the local strength of the press ring 3 during the four-corner trimming process.

Based on the tangent point between the flanging radius R of the part's flanging contour line 13 and the four-corner trimming line 12, extend the length c outward, and the outer end point of c is toward the intersection point of the drawing trimming knife and the four-corner trimming knife. The outer extension length d, the length of d is 2mm, the purpose is to ensure sufficient trimming connection between the drawing process and the trimming process.

The width direction dimension e of the four-corner trimming line 12, e is 5mm. The purpose is to take into account that there is single-sided trimming here and ensure the structural stability of the lateral force on the trimming insert.

Considering the processability of the trimming die 5 and the pressing ring 3, the rounding angle R is required, and the R size is at least 5 mm.

Treatment of the local parting line: In order to ensure the strength of the local blanking ring 3, the distance f between the four-corner trimming line 12 and the parting line 11 of the drawing die is 30 mm.

"Punching tongue (that is, the trimming waste is attached to the sheet 4, the same below)" The amount of trimming blade input is g, and the size of g is 1 mm.

"Punch tongue" trimming avoidance amount h, the size of h is 1mm.

Mold working process: The working process of the drawing and trimming composite mold combines the working processes of the drawing mold and the trimming mold. That is, when the drawing process is about to be completed, the partial trimming process is carried out. When the concave mold is drawn to the bottom, the drawing process and the trimming process are completed at the same time. The main working process of the mold is as follows:

When the drawing die 1 is 40mm away from the forming bottom, the drawing die 1 engages with the middle blank holder 3.1, the drawing die 1 continues to move downward, and the sheet 4 begins to be drawn and formed; the drawing die 1 is away from the stroke When the bottom is 1 mm, the trimming punch 6 begins to contact the sheet 4. At this time, the outer edge ring 3.2 acts as a pressing force relative to the trimming work. As the drawing die 1 continues to move downward, the trimming punch 6 punches. Enter the trimming die 5 and start trimming the four corners of the sheet 4. When the drawing die 1 moves to the bottom of the stroke, the drawing and trimming processes are completed.

By integrating the trimming mold on the drawing mold, the present invention reduces the processing steps and solves the structural defects of the front floor trimming and flanging composite mold itself. The parts are less likely to produce chips and burrs, and have high quality and robustness, and are easy to process and debug the mold. The requirements are low, the mold mass production status is stable in the later stage, and the quality of parts is effectively guaranteed. Compared with the three-step front floor process, the development of a set of stamping molds is reduced and the manufacturing cost of a set of molds is saved.

The above descriptions are only preferred embodiments of the present invention and do not impose any formal restrictions on the structure of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims (8)

1. A composite mold for drawing and trimming of automobile front floor, including a drawing die (1) and a drawing punch (2) arranged up and down, and a blanking ring is provided in the drawing punch (2) (3); It is characterized in that: the drawing die (1) and the drawing punch (2) are respectively provided with corresponding tools for trimming the four corners of the sheet material (4). The trimming die (5) and the trimming punch (6) are operated. The trimming punch (6) is located in the edge holder ring (3). There is a supply hole on the edge holder ring (3). A through hole passes through the top of the trimming punch (6); the drawing die (1) is provided with one of the trimming holes at the corresponding positions of the four corners of the sheet material (4). Trimming die (5); the drawing punch (2) is provided with one trimming punch (6) at positions corresponding to the trimming of the four corners of the sheet material (4); The blank holder (3) includes a central blank holder (3.1) located in the middle of the drawing punch (2) for compressing the central surface of the sheet material (4) and a central blank holder (3.1) located in the drawing punch (2). On the outside of the mold (2), there is an outer edge ring (3.2) used to compress the outer surface of the sheet material (4), and the trimming punch (6) is arranged between the middle edge ring (3.1) and between the outer edge rings (3.2); the trimming punch (6) adopts a trimming knife with a beveled top surface, and the trimming concave mold (5) adopts a trimming knife that matches the trimming knife. Trimming sleeve for shaft hole. 2. The composite mold for drawing and trimming the automobile front floor as claimed in claim 1, characterized in that: there are disposed under the outer edge holder (3.2) for pushing the outer edge holder (3.2) and the The drawing die (1) and the pushing structure prevent the mold edge of the drawing die (1) from contacting the die edge of the drawing punch (2). 3. The composite mold for drawing and trimming the automobile front floor as claimed in claim 2, characterized in that: the pushing structure includes four respectively disposed below the four corners of the outer edge ring (3.2). A push cylinder (7), the piston rod of the push cylinder (7) is connected to the bottom of the outer edge holder (3.2). 4. The composite mold for drawing and trimming of automobile front floor according to claim 1, characterized in that: the drawing concave mold (1) and the drawing convex mold (2) are respectively provided with mutually matching, A guide structure used to accurately match the trimming concave mold (5) and the trimming punch (6). 5. The composite mold for drawing and trimming of automobile front floor as claimed in claim 4, characterized in that: the guide structure includes a guide structure fixed in the drawing die (1) and located in the drawing die (1). Four guide sleeves (8) at the four corners of 1) and guide posts (9) fixed in the drawing punch (2) and located at the four corners of the drawing punch (2) . 6. A processing method based on the drawing and trimming composite mold of the automobile front floor according to any one of the above claims 1-5, characterized in that it includes: placing the sheet (4), drawing the concave mold ( 1) Move down, the drawing die (1) cooperates with the middle blank holder (3.1) to compress the middle surface of the sheet (4), and the drawing die (1) cooperates with the drawing punch (2) to align the plate The material (4) is drawn, the drawing die (1) continues to move downward, the drawing die (1) cooperates with the outer edge ring (3.2) to compress the outer surface of the sheet (4), and the trimming die (5) Cooperate with the trimming punch (6) to trim the four corners of the sheet (4), move the drawing die (1) upward, and take out the sheet (4). 7. The processing method of the drawing and trimming composite mold for the automobile front floor as claimed in claim 6, characterized in that: the trimming concave mold (5) and the trimming convex mold (6) cooperate with the sheet material (4 The method for trimming operations at the four corners of Match the trimming sleeve of the shaft hole, and the top part of the trimming knife is inserted into the sheet material (4) and enters the trimming sleeve. 8. The processing method of the drawing and trimming composite mold for the automobile front floor as claimed in claim 7, characterized in that: the height of the trimming blade into the sheet material (4) is 0.8mm-1.2mm.