阅读说明：本技术 电动汽车电池盒上盖板的成型工艺 (Forming process of upper cover plate of battery box of electric automobile ) 是由 方煜定 于 2020-05-14 设计创作，主要内容包括：本发明公开了一种电动汽车电池盒上盖板的成型工艺,板料从成型模具总成进入后,在成型模具总成内进行四次成型工序,分别为一次拉伸成型、二次修边冲孔成型、三次修边冲孔成型和整形成型。因此,通过多次成型后,可以有效消除现有技术中出现的常见问题,尤其是扭曲和开裂的问题得到最佳的解决,在成型过程中,降低主应变和副应变的差值,可以保证产品不开裂不起皱的前提下,减少扭曲,保证产品尺寸达到要求。(The invention discloses a forming process of an upper cover plate of a battery box of an electric automobile. Therefore, after multiple times of forming, common problems in the prior art can be effectively eliminated, particularly the problems of distortion and cracking are solved optimally, in the forming process, the difference value of main strain and auxiliary strain is reduced, the distortion is reduced on the premise that the product is not cracked and not wrinkled, and the size of the product is ensured to meet the requirements.)

1. The forming process of the upper cover plate of the battery box of the electric automobile is characterized in that: after the sheet material enters from the forming die assembly, four forming processes are carried out in the forming die assembly, and a pair of forming dies is arranged in each forming process, an upper die component of each pair of forming dies is connected to an upper die fixing plate of the forming die assembly, and a lower die component of each pair of forming dies is connected to a lower die fixing plate of the forming die assembly; the four molding processes sequentially comprise:

1) carrying out stretch forming through a first forming die to obtain a one-step forming semi-finished product, and forming a main plane (1-1), a flange peripheral ring (1-2), a middle rib (1-3), a supporting rib () and a groove (1-7) of the product from a blank plate; the upper die assembly presses and molds the middle rib (1-3) of the product before die assembly, and then molds the main plane (1-1), the flange periphery (1-2), the support rib (1-4) and the groove (1-7) of the product after die assembly;

2) carrying out primary trimming, punching and forming through a second forming die to obtain a secondary forming semi-finished product, punching a large mounting hole (1-5) on a groove (1-7) on the reinforcing bar (1-4) at the moment, and trimming the outline of the product;

3) carrying out secondary trimming, punching and forming through a third-time forming die to obtain a third-time formed semi-finished product, punching small mounting holes (1-6) on the periphery of the flange at the moment, and trimming the outline of the product again;

4) and shaping and forming through a fourth forming die to obtain a finished product, wherein in the step, the rebound phenomenon of the three-time formed semi-finished product after trimming and punching is shaped to enable the product to be trimmed to be flat.

2. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 1, wherein: the upper die assembly of the first-time forming die comprises an upper die box (2), an upper die plate (5) and a middle rib forming plate (4); the upper end of the upper mold box (2) is fixedly connected to the upper mold fixing plate, and the upper mold box (2) is of a box-type structure; the upper template (5) is connected in the upper template box (2), and the upper template (5) is provided with a containing hole (7) for containing the middle rib forming plate (4); a boss (6) is arranged on the bottom plane of the upper mold box (2), the upper end of the middle rib forming plate (4) is fixedly connected to the boss (6), and the middle rib forming plate (4) is positioned in the accommodating hole (7) of the upper mold plate (5); the lower end face of the middle rib forming plate (4) is a forming face of the middle rib (1-3), the lower end face of the upper template (5) is a forming face of a product main plane (1-1), a supporting rib (1-4) and a groove (1-7), the lower end face of the middle rib forming plate (4) protrudes out of the lower end face of the upper template (5), and the lower end face of the upper template (5) protrudes out of a box body end face of the upper template box (2).

3. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 2, wherein: the joint of the middle rib forming plate (4) and the boss (6) of the upper die box (2) is provided with three positioning structures which are respectively positioned in the middle and at two ends of the middle rib forming plate (4); the middle rib forming plate (4) and the boss (6) at each positioning structure are respectively provided with a semi-positioning groove, the middle rib forming plate (4) and the boss (6) are installed to form a complete positioning groove (10), and the positioning structures are clamped in the positioning grooves (10) through the positioning strips; the positioning strips in the middle part traverse the thickness of the middle rib forming plate (4), and the length directions of the positioning strips at the two ends are consistent with the length direction of the middle rib forming plate (4) and are positioned on the central line.

4. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 2, wherein: lugs (8) are arranged at the joint of the middle rib forming plate (4) and the upper die box (2), and a plurality of lugs (8) are arranged on two sides of the middle rib forming plate (4); correspondingly, the lug boss (6) is also provided with an extension table (9) matched with the lug (8).

5. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 1, wherein: in each pair of forming die, a limiting device is arranged between the upper die box (2) and the lower die frame in the lower die assembly, the limiting device comprises at least four limiting parts (11) distributed on the periphery of the lower die frame, the lower end of each limiting part (11) is connected with the lower die frame, and the upper end of each limiting part is positioned in the upper die box (2).

6. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 5, wherein: the number of the limiting pieces (11) is eight, two limiting pieces (11) are arranged on each side of the periphery of the lower die frame, and eight vacant grooves for vacant limiting pieces (11) are correspondingly formed in the lower end of the ground die box (2).

7. The forming process of the upper cover plate of the battery box of the electric automobile as claimed in claim 6, wherein: the limiting piece (11) comprises an L-shaped horizontal block (11-1) and a vertical block (11-2) which are connected into a whole, wherein the horizontal block (11-1) is fixedly connected to the lower die frame, and the vertical block (11-2) is accommodated in the accommodating groove of the upper die box (2); the side surface of the vertical block (11-2) facing the interior of the mold comprises a lower inclined surface (11-7), an upper inclined surface (11-3), a lower plane (11-6), a middle cambered surface (11-5) and an upper plane (11-4); the upper plane (11-4) is connected with the lower plane (11-6) up and down through the middle arc surface (11-5), the upper inclined surface (11-3) is connected with the lower inclined surface (11-7) up and down, the side edge formed by the upper inclined surface (11-3) and the lower inclined surface (11-7) is connected with the side edge formed by the upper plane (11-4), the middle arc surface (11-5) and the lower plane (11-6), and the other side edge formed by the upper plane (11-4), the middle arc surface (11-5) and the lower plane (11-6) is connected with the side edge formed by the other group of upper inclined surface (11-3) and the lower inclined surface (11-7).

Technical Field

The invention relates to the technical field of forming processes, in particular to a forming process of an upper cover plate of a battery box of an electric automobile.

Background

At present, as people's environmental awareness is getting stronger, more and more people select the electric automobile of new forms of energy as the instrument of riding instead of walk, and the battery case is as the important part among the electric automobile, and it is the load-bearing body of group battery, and it must have sufficient intensity to fix the group battery, and must possess effects such as dustproof, pleasing to the eye moreover. Generally, the battery box comprises an upper cover plate, as shown in figure 1, which comprises a rectangular main plane 1-1, wherein the periphery of the main plane 1-1 is a flange periphery 1-2 extending upwards the main plane, a plurality of small mounting holes 1-6 are arranged along the flange periphery 1-2, a middle rib 1-3 extending to two opposite sides of the main plane and protruding downwards the main plane is arranged in the middle of the main plane 1-1, the middle rib 1-3 is used as a boundary, a plurality of supporting ribs 1-4 perpendicular to the middle rib 1-3 and protruding upwards the main plane are respectively arranged on the main planes at two sides of the main plane, a concave groove 1-7 is further arranged on each part of the supporting ribs 1-4, and a large mounting hole 1-5 is arranged on each groove 1-7. The flange sealing structure has the advantages that the sealing requirement is required while the size is required to be accurate and the strength is high, so that the size requirement of a formed product is high, the sealing requirement after the flange is assembled cannot be leaked, and the flange sealing structure belongs to one of important parts for safety protection of electric appliances of electric vehicles. Because of the safety problem of automobile electricity, the requirement on the product is high, the thinning rate cannot exceed the standard during the molding process, the product cannot be cracked in dark, the surface cannot be wrinkled, and the flatness also meets the tolerance of the product. However, the product itself is large in size, and the overall length and width thickness reaches 1341mm × 1320mm × 21mm, so that the length and width of the product is large in size, and the height is relatively small. Furthermore, only the product with the thickness of 21mm needs to be internally provided with reinforcing ribs, so that the depth of the reinforcing ribs in the molded product is shallow, and the material thickness of the whole product is only 0.7 mm. Therefore, the forming difficulty of the upper cover plate of the battery box of the electric automobile is very high, basically, the product has no strength, and the internal stress distribution is unbalanced after forming. The reason for this imbalance is mainly that the primary strain (strain value in the direction of maximum elongation of the plane of the sheet) and the secondary strain (strain value in the direction perpendicular to the direction of maximum elongation of the plane of the sheet) are not balanced between the peripheral flange and the middle plane of the product, and the numerical difference is large, especially the secondary strain. In the prior art, the processing technology of the thin-wall large-plane part generally adopts the scheme that the part is formed and directly stretched through a forming die in one step, so that the product is extremely twisted, the twisting value is large and reaches more than +/-50 mm, and the dimensional requirement cannot be met at all.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a forming process of an upper cover plate of a battery box of an electric automobile, which can avoid the distortion and deformation of a formed product caused by a large difference value of primary and secondary strains during forming.

In order to solve the technical problem, the forming process of the upper cover plate of the battery box of the electric automobile provided by the invention has the advantages that after a plate enters from a forming die assembly, four forming processes are carried out in the forming die assembly, and a forming die is arranged in each forming process, an upper die component of each forming die is connected to an upper die fixing plate of the forming die assembly, and a lower die component of each forming die is connected to a lower die fixing plate of the forming die assembly; the four molding processes sequentially comprise:

1) carrying out stretch forming through a first forming die to obtain a one-step forming semi-finished product, and forming a main plane, a flange peripheral ring, an intermediate rib, a supporting rib and a groove of the product from a blank plate; the upper die assembly presses and molds the middle rib of the product before die assembly, and then molds the main plane, the flange periphery, the supporting ribs and the groove of the product after die assembly;

2) carrying out primary trimming, punching and forming through a second secondary forming die to obtain a secondary forming semi-finished product, punching a large mounting hole on the groove on the reinforcing bar, and trimming the outline of the product;

3) carrying out secondary trimming, punching and forming through a third-time forming die to obtain a third-time formed semi-finished product, punching a small mounting hole on the periphery of the flange at the moment, and trimming the outline of the product again;

4) and shaping and forming through a fourth forming die to obtain a finished product, wherein in the step, the rebound phenomenon of the three-time formed semi-finished product after trimming and punching is shaped to enable the product to be trimmed to be flat.

The upper die assembly of the first-time forming die comprises an upper die box, an upper die plate and a middle rib forming plate; the upper end of the upper mold box is fixedly connected to the upper mold fixing plate, and the upper mold box is of a box-type structure; the upper template is connected in the upper template box and is provided with a containing hole for containing the middle rib forming plate; the bottom plane of the upper mold box is provided with a boss, the upper end of the middle rib forming plate is fixedly connected to the boss, and the middle rib forming plate is positioned in the accommodating hole of the upper mold plate; the lower end face of the middle rib forming plate is a forming face of the middle rib, the lower end face of the upper template is a forming face of a main product plane, the supporting ribs and the grooves, the lower end face of the middle rib forming plate protrudes out of the lower end face of the upper template, and the lower end face of the upper template protrudes out of the box body end face of the upper template box.

The connecting part of the middle rib forming plate and the boss of the upper die box is provided with three positioning structures which are respectively positioned in the middle and at two ends of the middle rib forming plate; the middle rib forming plate and the boss at each positioning structure are respectively provided with a semi-positioning groove, the middle rib forming plate and the boss form a complete positioning groove after being installed, and the positioning structure is clamped in the positioning groove through the positioning strip; the positioning strips at the middle part cross the thickness of the middle rib forming plate, and the length directions of the positioning strips at the two ends are consistent with the length direction of the middle rib forming plate and are positioned on the central line.

Lugs are arranged at the joint of the middle rib forming plate and the upper die box, and are respectively arranged at two sides of the middle rib forming plate; correspondingly, the lug boss is also provided with an extension table matched with the lug.

In each pair of forming dies, a limiting device is arranged between the upper die box and the lower die frame in the lower die assembly, the limiting device comprises at least four limiting parts distributed on the periphery of the lower die frame, the lower end of each limiting part is connected with the lower die frame, and the upper end of each limiting part is positioned in the upper die box.

The number of the limiting parts is eight, two limiting parts are arranged on each side of the periphery of the lower die frame, and eight vacant limiting part vacant grooves are correspondingly formed in the lower end of the overground die box.

The limiting piece comprises an L-shaped horizontal block and a vertical block which are connected into a whole, wherein the horizontal block is fixedly connected to the lower die frame, and the vertical block is accommodated in the accommodating groove of the upper die box; the side surface of the vertical block facing the interior of the mold comprises a lower inclined surface, an upper inclined surface, a lower plane, a middle cambered surface and an upper plane; the upper plane and the lower plane are connected up and down through the middle cambered surface, the upper inclined surface and the lower inclined surface are connected up and down, the side edge formed by the upper inclined surface and the lower inclined surface is connected with the side edge formed by the upper plane, the middle cambered surface and the lower plane, and the other side edge formed by the upper plane, the middle cambered surface and the lower plane is connected with the side edge formed by the other group of upper inclined surface and the lower inclined surface.

After the forming process is adopted, compared with the prior art, the forming process has the following advantages:

1) after multiple forming, common problems in the prior art can be effectively eliminated, particularly the problems of distortion and cracking are optimally solved, and in the forming process, the difference value of main strain and auxiliary strain is reduced, so that the distortion is reduced on the premise that the product is not cracked and not wrinkled, and the size of the product is ensured to meet the requirements;

2) in the one-step forming die, the whole die cavity is of a sinking box type structure, so that the difference value of main and auxiliary strain is reduced to the minimum, and the distortion of a product is further reduced; the upper die and the lower die both adopt movable structures, the upper die component presses and forms the middle rib of the product before die assembly, and then forms other characteristics of the product after die assembly, thereby realizing the stretching process of the product;

3) the middle rib forming plate is connected with the upper die box, and a boss in the upper die box is utilized, so that the structure is simple, the processing is convenient, and the production cost is low; meanwhile, the connecting structure of the lug of the middle rib forming plate and the extension table of the boss ensures that the middle rib forming plate is stable outside the upper mold box, also fully utilizes the limited space in the mold, and has simple structure and convenient processing;

4) the positioning structure arranged between the middle rib forming plate and the upper mold box adopts a transverse and vertical staggered positioning mode, so that the position relation between the middle rib forming plate and the upper mold box is more accurate, and the size precision of a formed product is ensured.

Drawings

Fig. 1 is a schematic view of the structure of the components of the upper cover plate of the battery box of the electric vehicle related to the present invention.

Fig. 2 is a schematic structural diagram of a one-step forming die involved in the forming process of the upper cover plate of the battery box of the electric vehicle.

Fig. 3 is a schematic view of a partial explosion structure of an upper mold in the one-time forming mold of the present invention.

Fig. 4 is a schematic structural view of the intermediate rib forming plate and the upper mold box in fig. 3.

Fig. 5 is a schematic front view of the upper mold assembly in the one-step molding mold according to the present invention.

Fig. 6 is a schematic structural diagram of a limiting element according to the present invention.

Wherein: 1. an upper cover plate of a battery box of the electric automobile; 1-1, main plane; 1-2, flange circumference; 1-3 parts of middle ribs, 1-4 parts of branch ribs; 1-5, large mounting holes; 1-6, small mounting holes; 1-7, a groove; 2. putting the mold box; 3. a lower die; 4. forming a plate by using the middle ribs; 5. mounting a template; 6. a boss; 7. a housing hole; 8. a lug; 9. an extension stage; 10. positioning a groove; 11. a limiting member; 11-1, horizontal block; 11-2, vertical blocks; 11-3, an upper inclined plane; 11-4, upper plane; 11-5, a middle cambered surface; 11-6, lower plane; 11-7 and a lower inclined plane.

Detailed Description

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

As can be seen from the schematic structural diagrams of the dies in the forming process of the upper cover plate of the battery box of the electric vehicle shown in fig. 1 to 6, in the forming process of the upper cover plate of the battery box of the electric vehicle, after a plate enters from a forming die assembly, four forming processes are performed in the forming die assembly, and a forming die is arranged in each forming process, an upper die assembly of each forming die is connected to an upper die fixing plate of the forming die assembly, and a lower die assembly of each forming die is connected to a lower die fixing plate of the forming die assembly; the four molding processes sequentially comprise:

1) performing stretch forming through a first forming die to obtain a one-step forming semi-finished product, and forming a main plane 1-1, a flange periphery 1-2, an intermediate rib 1-3, a supporting rib and a groove 1-7 of the product from a blank plate; the upper die assembly presses and molds the middle rib 1-3 of the product before closing the die, and then molds the main plane 1-1, the flange periphery 1-2, the support rib 1-4 and the groove 1-7 of the product after closing the die;

2) carrying out primary trimming, punching and forming through a second forming die to obtain a secondary forming semi-finished product, punching large mounting holes 1-5 on grooves 1-7 on the reinforcing bar strips 1-4 at the moment, and trimming the outline of the product;

3) carrying out secondary trimming, punching and forming through a third-time forming die to obtain a third-time formed semi-finished product, punching small mounting holes 1-6 on the periphery of the flange at the moment, and trimming the outline of the product again;

4) and shaping and forming through a fourth forming die to obtain a finished product, wherein in the step, the rebound phenomenon of the three-time formed semi-finished product after trimming and punching is shaped to enable the product to be trimmed to be flat.

The upper die assembly of the first-time forming die comprises an upper die box 2, an upper die plate 5 and a middle rib forming plate 4; the upper end of the upper mold box 2 is fixedly connected to the upper mold fixing plate, and the upper mold box 2 is of a box-type structure; the upper die plate 5 is connected in the upper die box 2, and the upper die plate 5 is provided with a containing hole 7 for containing the middle rib forming plate 4; a boss 6 is arranged on the bottom plane of the upper mold box 2, the upper end of the middle rib forming plate 4 is fixedly connected to the boss 6, and the middle rib forming plate 4 is positioned in a containing hole 7 of the upper mold plate 5; the lower end face of the middle rib forming plate 4 is a forming face of a middle rib 1-3, the lower end face of the upper die plate 5 is a forming face of a main product plane 1-1, a supporting rib 1-4 and a groove 1-7, the lower end face of the middle rib forming plate 4 protrudes out of the lower end face of the upper die plate 5, and the lower end face of the upper die plate 5 protrudes out of the end face of the upper die box 2.

The joint of the middle rib forming plate 4 and the boss 6 of the upper die box 2 is provided with three positioning structures which are respectively positioned in the middle and at two ends of the middle rib forming plate 4; the middle rib forming plate 4 and the boss 6 at each positioning structure are respectively provided with a semi-positioning groove, the middle rib forming plate 4 and the boss 6 are installed to form a complete positioning groove 10, and the positioning structure is clamped in the positioning groove 10 through the positioning strip; the positioning strips in the middle cross the thickness of the middle rib forming plate 4, and the length directions of the positioning strips at two ends are consistent with the length direction of the middle rib forming plate 4 and are positioned on the central line.

Lugs 8 are arranged at the joint of the middle rib forming plate 4 and the upper die box 2, and a plurality of lugs 8 are arranged on two sides of the middle rib forming plate 4; correspondingly, the extension 9 matching the lug 8 is also arranged on the boss 6.

In each pair of forming dies, a limiting device is arranged between the upper die box 2 and the lower die frame in the lower die assembly, the limiting device comprises at least four limiting parts 11 distributed on the periphery of the lower die frame, the lower end of each limiting part 11 is connected with the lower die frame, and the upper end of each limiting part is positioned in the upper die box 2.

The number of the limiting pieces 11 is eight, two limiting pieces 11 are arranged on each side of the periphery of the lower die frame, and eight vacant limiting piece 11 vacant grooves are correspondingly formed in the lower end of the ground die box 2.

The limiting piece 11 comprises an L-shaped horizontal block 11-1 and a vertical block 11-2 which are connected into a whole, wherein the horizontal block 11-1 is fixedly connected to the lower die frame, and the vertical block 11-2 is accommodated in the accommodating groove of the upper die box 2; the side surface of the vertical block 11-2 facing the interior of the mold comprises a lower inclined surface 11-7, an upper inclined surface 11-3, a lower plane 11-6, a middle cambered surface 11-5 and an upper plane 11-4; the upper plane 11-4 is connected with the lower plane 11-6 up and down through the middle arc surface 11-5, the upper inclined surface 11-3 is connected with the lower inclined surface 11-7 up and down, the side edge formed by the upper inclined surface 11-3 and the lower inclined surface 11-7 is connected with the side edge formed by the upper plane 11-4, the middle arc surface 11-5 and the lower plane 11-6, and the other side edge formed by the upper plane 11-4, the middle arc surface 11-5 and the lower plane 11-6 is connected with the side edge formed by the other group of the upper inclined surface 11-3 and the lower inclined surface 11-7.

The above description is only a preferred embodiment of the present invention, and it should not be understood that the scope of the present invention is limited thereby, and it should be understood by those skilled in the art that various other modifications and equivalent arrangements can be made by applying the technical solutions and concepts of the present invention within the scope of the present invention as defined in the appended claims.