阅读说明：本技术 提升机盖内板材料利用率的拉延工艺 (Drawing process for material utilization rate of inner plate of lifter cover ) 是由 康春华 尹永铎 况亚 于 2021-09-30 设计创作，主要内容包括：本发明提供了提升机盖内板材料利用率的拉延工艺,属于汽车零件制造工艺领域,包括浮动上模,作为凹模,相对凸模上下运动,对坯料进行冲压,对小行程压边圈施力,以使得制件预压定位；浮动上模包括上模型腔和浮动压料器,浮动压料器设在上模型腔一侧的下端,浮动压料器的上短语上模型腔之间设有弹簧件；小行程压边圈,设在坯料靠近风窗侧,用于控制材料流速,小行程压边圈在浮动压料器的预压力作用下对坯料进行预压定位；常规行程压边圈,包在小行程压边圈的外圈,控制拉延过程中材料流速。本发明既保证制件品质,又大幅度的提升材料利用率；在品质保障的前提下,汽车制作成本大幅度降低。(The invention provides a drawing process for the utilization rate of a material of an inner plate of a cover of an elevator, belonging to the field of automobile part manufacturing processes, comprising a floating upper die which is used as a female die, moves up and down relative to a male die, punches a blank, and applies force to a small-stroke blank holder so as to prepress and position a workpiece; the floating upper die comprises an upper die cavity and a floating material pressing device, the floating material pressing device is arranged at the lower end of one side of the upper die cavity, and a spring part is arranged between the upper phase of the floating material pressing device and the upper die cavity; the small-stroke blank holder is arranged on the side, close to the air window, of the blank and used for controlling the flow rate of the material, and the small-stroke blank holder performs prepressing positioning on the blank under the action of prepressing force of the floating material pressing device; and the conventional stroke blank holder is wrapped on the outer ring of the small stroke blank holder to control the material flow rate in the drawing process. The invention not only ensures the quality of the finished piece, but also greatly improves the utilization rate of materials; on the premise of quality guarantee, the manufacturing cost of the automobile is greatly reduced.)

1. Drawing process of lifter cover inner plate material utilization ratio, its characterized in that: the floating upper die is used as a female die, moves up and down relative to a male die, punches a blank, and applies force to a small-stroke blank holder so as to prepress and position a workpiece;

the floating upper die comprises an upper die cavity and a floating material pressing device, the floating material pressing device is arranged at the lower end of one side of the upper die cavity, and a spring part is arranged between the upper phase of the floating material pressing device and the upper die cavity;

the small-stroke blank holder is arranged on the side, close to the air window, of the blank and used for controlling the flow rate of the material, and the small-stroke blank holder performs prepressing positioning on the blank under the action of prepressing force of the floating material pressing device;

the conventional stroke blank holder is arranged on the outer ring of the blank and wrapped on the outer ring of the small stroke blank holder, the material flow rate in the drawing process is controlled, and the blank is positioned continuously downwards after the small stroke blank holder positions the blank.

2. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 1, wherein the drawing process comprises the following steps: the elastic piece is a nitrogen cylinder or a nitrogen spring.

3. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 1, wherein the drawing process comprises the following steps: the working area of the floating upper die is from the top leg of the male die to the boundary of the blank; the inner starting edge of the small-stroke blank holder is a finished piece boundary, the outer end edge of the small-stroke blank holder is larger than a blank boundary, and the small-stroke blank holder is arranged on the inner side of the conventional stroke blank holder;

according to the conventional stroke blank holder, the starting edge on the inner side is a finished piece boundary, and the finishing edge on the outer side is larger than a blank boundary.

4. The drawing process of the utilization rate of the plate material in the elevator cover as claimed in any one of claims 1 to 3, wherein: the upper floating die is widened to cover the blank of the workpiece towards the side of the wind window, the widened area is the supplement width H, a small-stroke blank holder is installed in the reserved space, and the height of the upper end face of the small-stroke blank holder is larger than that of the upper end face of the conventional stroke blank holder.

5. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 4, wherein the drawing process comprises the following steps: the complementary width H is 20-50 mm.

6. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 5, wherein the drawing process comprises the following steps: the complementary width H is 23-28 mm.

7. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 1, wherein the drawing process comprises the following steps: the supplement height h is the height from the highest point to the blank holder after the finished piece is formed, the supplement height h1 is set after the floating upper die and the small-stroke blank holder are arranged, and h1 is between 2/3 and 3/4 of h.

8. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 7, wherein the drawing process comprises the following steps: with the determination of the value of h1, after the part is drawn, the fillet of the concave die is reduced from Ra to Rb, and the angle of the drawing angle alpha is reduced.

9. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 8, wherein the drawing process comprises the following steps: rb is 6-10 mm.

10. The drawing process for the utilization rate of the plate material in the elevator cover as claimed in claim 8, wherein the drawing process comprises the following steps: the lower extreme of little stroke blank holder is equipped with and is equipped with the first mound pad of spacing to it, the lower extreme of conventional stroke blank holder is equipped with and is equipped with the second mound pad of spacing to it, the upper end of first mound pad is higher than the upper end of second mound pad, the difference in height of two kinds is h ', h' is 1/4 to 1/3 of supplementary height h.

Technical Field

The invention belongs to the field of automobile part manufacturing processes, and relates to a drawing process for improving the utilization rate of a plate material in a machine cover.

Background

The development of the domestic automobile industry is leap forward in the year, and the manufacturing cost of each automobile enterprise from a single product to an assembly is more and more refined. The stamping parts are used as important components of the body-in-white, so that the cost of the stamping parts is effectively reduced, and the effect of reducing the manufacturing cost of the whole vehicle is very obvious.

The cover inner panel is located the inboard of cover, forms holistic sheet metal construction with the cover, plays the effect of support and enhancement to the intensity of cover, receives the in-process of striking at the cover simultaneously, can bear the impact, predetermines the deformation direction, can play the effect of protection to cover and automobile body.

For the conventional inner cover plate, the difficulty of drawing and forming is mainly concentrated at two positions a and b shown in fig. 1: because the hinge mounting surface is limited, the position a is an area where a plurality of arc surfaces intersect, two sharp points are easy to crack, and the material thinning and increasing are controlled by increasing the material flow; because the molding restriction, the b position is fillet structure, sunken state, and the shaping process produces the fold easily and leads to the lid inner panel unqualified and the lid inside and outside board assembly of borduring to produce the wave defect, and the solution is for the control material flows, avoids unnecessary material to flow in.

The conventional process means adopts a closed drawing design, increases the supplement of two corners of the air window, controls the material flow, solves the defects of a and b in the figure 1, the supplement of the drawing process needs enough space, the blank must be ensured to be 5-10mm outside a drawing rib after being drawn, the qualification rate of the product is ensured, the blank holder modeling must be smooth, the supplement height h of the air window cannot be reduced (figure 3), the serious abrasion of the blank holder caused by the fold and the forming of a finished piece when an upper die and the blank holder are closed is avoided, and meanwhile, the utilization rate of the plate of the scheme is usually 45-53 percent by considering different factors of the product modeling.

Disclosure of Invention

The invention aims to provide a drawing process for improving the utilization rate of a plate material in a machine cover, which not only ensures the quality of a workpiece, but also greatly improves the utilization rate of the material; on the premise of quality guarantee, the manufacturing cost of the automobile is greatly reduced.

In order to solve the technical problems, the invention adopts the technical scheme that: the drawing process for improving the utilization rate of the plate material in the machine cover comprises a floating upper die which is used as a female die and moves up and down relative to a male die to stamp a blank and apply force to a small-stroke blank holder so as to prepress and position a workpiece;

the floating upper die comprises an upper die cavity and a floating material pressing device, the floating material pressing device is arranged at the lower end of one side of the upper die cavity, and a spring part is arranged between the upper phase of the floating material pressing device and the upper die cavity;

the small-stroke blank holder is arranged on the side, close to the air window, of the blank and used for controlling the flow rate of the material, and the small-stroke blank holder performs prepressing positioning on the blank under the action of prepressing force of the floating material pressing device;

the conventional stroke blank holder is arranged on the outer ring of the blank and wrapped on the outer ring of the small stroke blank holder, the material flow rate in the drawing process is controlled, and the blank is positioned continuously downwards after the small stroke blank holder positions the blank.

Further, the elastic piece is a nitrogen cylinder or a nitrogen spring.

Further, the working area of the floating upper die is from the top leg of the male die to the boundary of the blank; the inner starting edge of the small-stroke blank holder is a finished piece boundary, the outer end edge of the small-stroke blank holder is larger than a blank boundary, and the small-stroke blank holder is arranged on the inner side of the conventional stroke blank holder;

according to the conventional stroke blank holder, the starting edge on the inner side is a finished piece boundary, and the finishing edge on the outer side is larger than a blank boundary.

Furthermore, the floating upper die is widened to cover the blank of the workpiece towards the side of the air window, the widened area is the supplement width H, a small-stroke blank holder is installed in the reserved space, and the height of the upper end face of the small-stroke blank holder is larger than that of the upper end face of the conventional stroke blank holder.

Further, the complementary width H is 20-50 mm.

Further, the complementary width H is 23-28 mm.

Further, the supplement height h is the height from the highest point to the blank holder after the finished piece is formed, after the floating upper die and the small-stroke blank holder are arranged, the supplement height h1 is set, and h1 is between 2/3 and 3/4 of h.

Further, with the determination of the value of h1, after the part is drawn, the fillet of the concave die is reduced from Ra to Rb, and the angle of the drawing angle alpha is reduced.

Further, Rb is 6-10 mm.

Furthermore, the lower end of the small-stroke blank holder is provided with a first dead pad for limiting the small-stroke blank holder, the lower end of the conventional stroke blank holder is provided with a second dead pad for limiting the conventional stroke blank holder, the upper end of the first dead pad is higher than the upper end of the second dead pad, and the height difference between the first dead pad and the second dead pad is h ', h' is 1/4 to 1/3 of the supplement height h.

Compared with the prior art, the invention has the following advantages and positive effects.

1. The floating upper die is arranged, the specification of a blank to be formed is reduced by reducing the supplement width of the air window side and the drawing depth of the air window side, the utilization rate of the material can be greatly improved, the utilization rate can be improved to 65-70 percent by the mode, and the cost is obviously reduced for the manufacture of a whole vehicle;

2. the drawing depth H, the drawing angle alpha and the air window supplement width H of the workpiece directly affect the quality and the material utilization rate of the workpiece, and the three parameters are reduced, so that the utilization rate is improved on the premise of ensuring the strength;

3. the application designs new mould structure, and the cooperation is accomplished technological parameter's settlement and completion, reduces wind window side and draws and to prolong supplementary draft angle a, and mould intensity increases on floating, and supplementary width H value contracts, guarantees that the blank holder is smooth and reduce drawing depth H value, and effective control velocity of flow, blank holder irregularity can lead to drawing die closing in-process, and the blank takes place more sharp change, leads to the blank holder to corrugate and causes serious wear and the unable assurance of finished piece quality to the mould.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a prior art configuration of the present invention;

FIG. 2 is a schematic structural diagram of a part applied in a drawing process for improving the utilization rate of a plate material in a cover of a machine;

FIG. 3 is a cross-sectional view A-A of FIG. 2 of the present invention;

FIG. 4 is an enlarged view of a portion of FIG. 2 of the present invention;

FIG. 5 is a top layout view of a die for a drawing process utilizing board material in a lifter cover according to the present invention;

FIG. 6 is a schematic view of a part after the drawing process of the present invention for improving the utilization rate of the plate material in the cover is applied;

fig. 7 is a sectional view of a die structure adopted by a drawing process for improving the utilization rate of plate materials in a machine cover.

Reference numerals:

1-floating the upper die; 2. an elastic member; 3. a floating swager; 4. a small-stroke blank holder; 5. a conventional stroke blank holder; 6. A first dead-mound pad; 7. a second dead-pier cushion; 8. and (4) a male die.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The following detailed description of specific embodiments of the invention refers to the accompanying drawings.

Body-in-white: refers to a vehicle body structure and panel welded assembly, and includes a front wing panel, a door, a hood, and a trunk lid, but does not include an unpainted vehicle body of accessories and trim parts. The coated white car body is provided with an inner decoration, an outer decoration (comprising an instrument board, a seat, windshield glass, a carpet, an inner decoration guard plate and the like), an electronic and electrical system (a sound system, a wire harness, a switch and the like), a chassis system (comprising a brake system, a suspension system and the like) and a power assembly system (comprising an engine, a gearbox and the like) to form the whole car.

Drawing, also called drawing, stretching, calendering, etc., refers to a mechanical processing technique for punching a flat blank with a certain shape obtained after blanking into various open hollow parts or reducing the diameter of the open hollow blank to increase the height by using a die. The product can be made into cylindrical, stepped, conical, spherical, box-shaped and other irregular thin-wall parts by deep drawing. The method can be matched with other stamping forming processes such as flanging, bulging, flaring and necking, and can also be used for manufacturing parts with extremely complex shapes. Therefore, in the production process of industrial departments such as automobiles, airplanes, tractors, electrical appliances, instruments, electronics and the like, the drawing process occupies a very important position, and the thickness of the blank drawn by the inner plate of the automobile is generally between 0.6 and 0.8 mm.

Blank holder: in the deep drawing process, in order to prevent the mouth edge part of the workpiece from buckling and wrinkling, the ring-shaped pressing device is arranged at the edge part between the female male die and the male die, the control of variable blank holder force is realized by utilizing a mechanical structure, and compared with the control of variable blank holder force realized by utilizing digital equipment, the cost is greatly reduced, and the ring-shaped pressing device is compact in structure and high in practicability.

And (3) drawing beads: the convex rib structure is generally arranged on the blank holder, and corresponding rib grooves, namely concave ribs, are formed on the surface of the female die. The convex rib can be arranged on the surface of the female die, the concave rib is arranged on the blank holder, and the effect of the draw bead is as follows 1, the control capability of the material pressing surface on the material flow is enhanced; 2. the feeding resistance is increased, so that the blank bears enough tensile stress, the rigidity of a deep-drawing part is improved, and the surface defects caused by resilience are reduced; 3. the adjusting range of the edge pressing force is expanded, the edge pressing force and the drawing bead supplement each other, and the edge pressing force can be reduced by adjusting the resistance of the drawing bead to achieve the same purpose; the constraining force of the draw bead is too small, so that the draw bead is easy to wrinkle; the drawing rib has overlarge restraint force and is easy to crack.

The molded surfaces of the side pressing rims of the air windows are almost smooth, the side pressing rims of the air windows are the positions with the maximum drawing depth, the drawing depth (h value in figure 3) of the side pressing rims of the air windows is usually 70-85 mm, and if the drawing depth of the position is regulated, the molded surfaces of the side pressing rims are not smooth, and the upper die and the side pressing rims are closed too heavily; if the h value is larger, in order to ensure that the forming is not cracked, the drawing angle (alpha value in figure 3) at the position needs to be 35-45 degrees to ensure that the blank is enlarged, the requirement that the drawn blank is 5-10mm away from the draw bead can be met, and the quality of a finished piece is ensured.

As shown in fig. 1-7, the invention relates to a drawing process for the utilization rate of a plate material in a lifter cover, which comprises a floating upper die 1 which is used as a female die and moves up and down relative to a male die 8 to stamp a blank and apply force to a small-stroke blank holder 4 so as to prepress and position a workpiece;

the floating upper die 1 comprises an upper die cavity and a floating material pressing device 3, the floating material pressing device 3 is arranged at the lower end of one side of the upper die cavity, a spring part is arranged between the upper die cavity and the floating material pressing device 3, and preferably, the elastic part 2 is a nitrogen cylinder or a nitrogen spring.

The small-stroke blank holder 4 is arranged on the side, close to the air window, of the blank and is used for controlling the flow rate of the material, and the small-stroke blank holder 4 performs prepressing positioning on the blank under the action of prepressing force of the floating material pressing device 3; and the conventional stroke blank holder 5 is arranged on the outer ring of the blank and wrapped on the outer ring of the small stroke blank holder 4, the material flow rate in the drawing process is controlled, and the blank is positioned continuously downwards after the small stroke blank holder 4 positions the blank downwards.

Preferably, the working area of the floating upper die 1 is from the top leg of the male die 8 to the boundary of the blank; the inner starting edge of the small-stroke blank holder 4 is a workpiece boundary, the outer end edge is larger than a blank boundary, and the small-stroke blank holder 4 is arranged on the inner side of the conventional stroke blank holder 5;

and in the conventional stroke blank holder 5, the starting edge of the inner side is a finished piece boundary, and the finishing edge of the outer side is larger than a blank boundary.

Preferably, the floating upper die 1 is widened to cover the blank of the workpiece towards the wind window side, the widened area is the supplement width H, the small-stroke blank holder 4 is installed in the reserved space, and the height of the upper end face of the small-stroke blank holder 4 is larger than that of the upper end face of the conventional stroke blank holder 5.

Preferably, the complementary width H is 20-50 mm; more preferably, the complementary width H is 23-28 mm; more preferably, the complementary width H is 25mm, the smaller the size of the floating upper die, the better.

Preferably, the supplement height h is the height from the highest point to the blank holder after the finished piece is formed, after the floating upper die 1 and the small-stroke blank holder 4 are arranged, the supplement height h1 is set, and h1 is within 2/3-3/4 of h, so that the size of the blank can be reduced, preferably, after the finished piece is drawn and extended, the fillet of the female die is reduced from Ra to Rb, the angle of the die drawing angle alpha is reduced, and the qualification rate of the position a in fig. 1 is improved. Preferably, Rb is 6-10mm, preferably 8mm, and after the numerical value is reduced, the quality and the utilization rate of the finished product are further improved.

Preferably, the lower end of the small-stroke blank holder 4 is provided with a first dead pad 6 for limiting the small-stroke blank holder, the lower end of the conventional stroke blank holder 5 is provided with a second dead pad 7 for limiting the small-stroke blank holder, the upper end of the first dead pad 6 is higher than the upper end of the second dead pad 7, the height difference between the two types of dead pads is h ', h' is 1/4-1/3 for supplementing the height h, and the prepressing force and the stability of the workpiece in the drawing process are guaranteed.

In actual working process, the cover inner panel is the draw mode of opening in this application, because the draw of opening does not have sufficient control power to the material flow, so need go up the mould structure split of tradition and go up a mould that floats, go up mould cavity and unsteady swager promptly, carry out the pre-compaction through unsteady swager to little stroke blank holder, little stroke blank holder carries out the pressfitting with the material of this side in advance, the velocity of flow and the flow direction of control material, both satisfy the required material of finished piece forming process, it is surplus and produce the defect to control the material inflow again, move the mould and need consider to arrange nitrogen cylinder, the intensity of foundry goods, the air window side complementary width H that the mould corresponds that floats is preferred 25mm, guarantee the foundry goods productivity of mould.

The working process of the die is as follows:

(1) when the mold is in an open state, the small-stroke blank holder and the conventional-stroke blank holder are synchronously supported through the lower air cushion ejector rod of the machine tool, and the profiles of the small-stroke blank holder and the conventional-stroke blank holder are smooth when the small-stroke blank holder and the conventional-stroke blank holder are completely supported due to stroke difference;

(2) the floating upper die moves downwards, the floating material pressing device is contacted with the small-stroke blank holder firstly, the floating material pressing device compresses firstly due to the small force of the nitrogen cylinder, after the upper die cavity is contacted with the blank holder completely, the upper die cavity and the two blank holders are controlled by adjusting the pads, and the floating upper die integrally (the upper die cavity + the floating material pressing device) and the blank holders (the conventional stroke blank holder + the small-stroke blank holder) synchronously carry out the drawing forming process downwards.

(3) After the small-stroke blank holder contacts the first dead pad on the male die, the small-stroke blank holder has no stroke, the upper die cavity continues to move downwards, and the upper floating material pressing device continues to compress and does not move downwards.

(4) And (4) continuing the last stroke of the upper die cavity and the conventional stroke blank holder, and drawing to the bottom until the upper die cavity and the conventional stroke blank holder are in contact limit with a second dead pad.

The drawing work of the whole inner plate of the machine cover is completed in the steps, the formed blank is taken out after the mould is opened, the next blank is put in, and the process is repeated.

The process can improve the material utilization rate to 65-70%, and greatly reduce the acceptance rate, such as: the cost of raw materials is 20 yuan, 3-7 blocks can be saved after lifting, the cost is reduced to 13-17, the difference cost of 5 burrs is very large for batch production, the vehicle model input yield is large because of considering the cost of a die and the like, the vehicle mass production is generally 50 tens of thousands of vehicles, and the cost is in conflict in the batch process.

The cost is reduced on the premise of ensuring the quality, the safety coefficient of a plurality of enterprises is set to be higher, but along with the fierce competition, the cost control becomes a competition key factor on the premise of ensuring the quality, the unit cost is reduced on the premise of volume production, the contribution degree to the overall cost control is high, the cost of the part is reduced by 1/7 or even 1/3 through the improvement of the process, and the breakthrough is further realized.

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.