CN103586342B - Drawing die - Google Patents

Abstract

A drawing die includes an upper die and a lower die. The upper mold has a forming surface for forming the part. The lower mold includes a lower mold base, a mold core fixed on the lower mold base and a blank holder that can slide relative to the mold core. The core has a core surface corresponding to the molding surface. The lower mold has an installation through hole that runs through the surface of the mold core and a lower movable block that can slide along the installation through hole. The blank holder is located in the first, second and third positions in turn during the processing of the parts. When the blank holder is at the first position, the blank is clamped between the blank holder and the upper die, and is in contact with the lower movable block; when the blank holder moves from the first position to the second position, the lower movable block The block touches the blank, and the blank is pre-drawn; when the blank holder moves from the second position to the third position, the lower movable block moves downward, and the blank is formally drawn by the mold face. The lower movable block has the function of supporting the blank, which can prevent the wrinkling and insufficient rigidity defects caused by the blank's own weight when stamping large parts.

Description

Drawing die

technical field

The invention relates to the field of special tools for stamping technology, in particular to a drawing die.

Background technique

Existing drawing dies include upper die, lower die and blank holder. The upper mold and the lower mold respectively include an upper mold core and a lower mold core. The upper mold core is used to surround the lower mold core to form a cavity consistent with the part to be drawn. The blank holder is usually located on the lower film and is used to fix the blank used for drawing. When stamping and forming, the upper mold moves toward the lower mold, and clamps the edge of the blank between the upper mold and the blank holder; then, the upper mold continues to move downward, and together with the lower film, the rest of the blank Press it into the cavity formed between the upper film core and the lower mold core, and draw the blank into the parts to be processed.

During the drawing and forming process of the blank, quality defects such as wrinkles often occur due to insufficient rigidity and other reasons. Common large-scale cladding parts, such as some parts in the roof, hood, side panels, rear doors, etc. of the car, such as the top cover, due to their simple geometry and small curvature, the blank is large at the beginning of stretching. The area is attached to the surface of the mold core, which increases the tensile resistance of the blank, resulting in insufficient stretching and insufficient rigidity; and for some other parts, such as the back door, due to the mold core shape of the drawing mold The cavity is large, and the supporting surface of the blank on the blank holder is small, so that the middle part of the blank is easy to sag under the action of its own weight, resulting in a large storage of the blank before stretching, resulting in insufficient stretching and insufficient rigidity. Insufficient stiffness will not only affect the appearance, but also reduce the structural strength of the part.

Contents of the invention

In view of this, the present invention provides a drawing die that can avoid the problem of insufficient rigidity of parts after stretching.

The invention provides a drawing die, which includes an upper die, a lower die and a blank holder; the upper die has a molding surface for forming parts, and the lower die includes a lower die base and a mold fixed to the lower die base. A mold core, the mold core has a mold core surface corresponding to the molding surface, the blank holder moves up and down relative to the mold core during the drawing forming process, and the blank of the part is sandwiched between the Between the blank holder and the upper die, and through the change of the relative position between the blank holder, the molding surface and the mold core surface, the molding surface and the mold core Drawing is performed facing the blank; the lower mold is provided with an installation through hole that penetrates the mold core surface and a lower movable block that can move in the installation through hole; the lower movable block is always in the drawing process. Contact with the billet and pre-draw the billet during one of the stages in the draw forming process.

As a further improvement of the present invention, the blank holder is sequentially located at the first position, the second position and the third position during the working process of the drawing die; when the blank holder is located at the first position, The blank is sandwiched between the blank holder and the upper die, and is in contact with the lower movable block; when the blank holder moves from the first position to the second position, The lower movable block presses against the blank to pre-draw the blank; when the blank holder moves from the second position to the third position, the lower movable block moves downward, and the The core surface and the forming surface are formally drawn from the blank.

As a further improvement of the present invention, the upper mold includes an upper mold base and an upper movable block, the upper mold base is provided with an accommodation through hole penetrating through the molding surface, and the upper movable block is accommodated in the accommodation through hole. hole and can move in the accommodating through hole, the upper movable block is away from the blank when the blank holder is at the first position, and when the blank holder moves from the first position to the second During the movement of the second position, it gradually approaches the blank, and when the blank holder moves from the second position to the third position, it presses against the blank first, and then moves upward relative to the upper die seat.

As a further improvement of the present invention, the initial pressure of the upper movable block is greater than the supporting force of the lower movable block, and during the process of moving the blank holder from the second position to the third position, the The upper movable block first presses the lower movable block to move downward, and then moves upward relative to the upper die seat.

As a further improvement of the present invention, the drawing die further includes: a first nitrogen gas spring connected to the lower movable block, a second nitrogen gas spring connected to the upper movable block, and a nitrogen gas spring connected to the blank holder putter.

As a further improvement of the present invention, between the lower movable block and the first nitrogen gas spring, between the upper movable block and the second nitrogen gas spring, and between the blank holder and the lower mold seat There is a bottom pad between them.

As a further improvement of the present invention, between the blank holder and the mold core, between the blank holder and the upper mold seat, between the lower movable block and the hole wall of the installation through hole, And a guiding wear-resistant plate is provided between the upper movable block and the hole wall of the receiving through hole.

As a further improvement of the present invention, the blank holder includes a support profile for carrying the blank and a mounting table surface recessed downward relative to the support profile, and a balance pad is provided between the mounting table and the upper mold.

The present invention also provides a method for processing parts by using the above-mentioned drawing die, which includes: moving the upper die upward, opening the drawing die; moving the blank holder and the lower movable block upward, and making the top surface of the lower movable block It is flush with the supporting surface of the blank holder; place the blank on the supporting surface of the blank holder and the lower movable block; move the upper die down, and sandwich the blank between the blank holder and the upper die; The edge ring and the upper mold move down, and the blank is pre-stretched by the lower movable block; the blank holder and the upper mold continue to move down, and the lower movable block moves down relative to the mold core, and the mold core surface and the forming surface are used to The billet is formally drawn.

As a further improvement of the present invention, the upper mold includes an upper mold base and an upper movable block, the upper mold base is provided with an accommodation through hole penetrating through the molding surface, and the upper movable block is accommodated in the accommodation through hole. hole and can move in the receiving through hole, the method of processing parts also includes: making the upper movable block move down relative to the upper mold base; moving the upper movable block and the upper mold base together, clamping the blank Between the blank holder and the upper die base; make the upper movable block and the upper die base continue to move down until the upper movable block is in contact with the blank; make the upper movable block and the upper die base move further down together, and make the upper movable block Push down the movable block and move down relative to the mold core; make the upper movable block and the upper die base move down further, use the upper movable block to push the billet, and make the upper movable block move up relative to the upper die base.

The beneficial effects of the present invention are:

The drawing die of the present invention adds a lower movable block to the lower die base, so that the billet is pre-stretched through the lower movable block, which can prevent the billet from adhering to the mold surface in a large area, and increase the tensile resistance of the billet. This leads to insufficient stretching, which ensures the rigidity of the blank during the drawing process. In addition, the lower movable block supports the billet, which can effectively prevent the center of the billet from sinking too much into the mold cavity due to the weight of the billet during stamping of large parts, which increases the probability of wrinkling and insufficient rigidity when the cover is formed.

The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the following preferred embodiments are specifically cited below, and are described in detail as follows in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a schematic partial sectional view of a drawing die in a preferred embodiment of the present invention.

Fig. 2 is a schematic partial cross-sectional view of the drawing die in Fig. 1 in a mold-opening state.

Fig. 3 is a schematic partial cross-sectional view of the drawing die in Fig. 1 in a closed state.

FIG. 4 is a schematic partial cross-sectional view of the drawing die in FIG. 1 in a pre-drawing state.

FIG. 5 is a schematic partial cross-sectional view of the drawing die in FIG. 1 in a drawing state.

Fig. 6 is a schematic partial cross-sectional view of the drawing die in Fig. 1 at the end of drawing.

Fig. 7 is a schematic partial cross-sectional view of a drawing die of another embodiment of the present invention at the end of drawing.

detailed description

In order to further explain the technical means and effects adopted by the present invention to achieve the intended invention purpose, the specific implementation, structure, features and effects of the present invention will be described in detail below in conjunction with the accompanying drawings and preferred embodiments.

Please refer to FIG. 1 , an embodiment of the present invention provides a drawing die for drawing a blank 2 into a desired processed part. The drawing die includes a machine platform 1 , an upper die 3 , a lower die 5 and a blank holder 7 . The blank holder 7 is used to fix the blank 2 . The machine table 1 is used to control the movement of the upper die 3 and the lower die 5, so that the upper die 3 and the lower film 5 are combined to draw the blank 2 into the parts to be processed.

Please refer to FIG. 2 , the machine platform 1 includes an upper machine platform 11 , a lower machine platform 13 and a driving member 15 . The upper machine platform 11 and the lower machine platform 13 are arranged oppositely, and the upper machine platform 11 and the lower machine platform 13 are respectively connected with power components (not shown) such as electric motors, and the upper machine platform 11 and the lower machine platform 13 are driven by power components such as electric motors Move upward or downward along the vertical direction in Figure 2 to approach or move away from each other. The upper platform 11 includes a mounting surface 111 facing the lower platform 13 . The upper mold 3 is fixed on the installation surface 111 and can move upwards or downwards with the upper platform 11 ; the lower platform 13 includes an installation surface 131 facing the upper platform 11 . The lower film 5 is fixed on the installation surface 131 and can move up or down with the lower machine platform 13 . The driver 15 includes a push rod 151 , a first nitrogen spring 153 and a second nitrogen spring 155 . Among them, the push rod 151 is fixed on the lower machine platform 13, and its upper end is connected with the blank holder 7, and the lower end of the push rod 151 can be connected with power components such as air cylinders or hydraulic cylinders, and the push rod 151 is driven by power components such as air cylinders or hydraulic cylinders. The blank holder 7 moves upward or downward along the vertical direction in FIG. 2 . The second nitrogen gas spring 155 is fixed on the upper machine platform 11 , and the first nitrogen gas spring 153 is fixed on the lower machine platform 13 . Moreover, a first spacer 154 is provided between the second nitrogen gas spring 155 and the upper machine platform 11 , and between the first nitrogen gas spring 153 and the lower machine platform 13 . It should be noted that, in the embodiment of the present invention, the driving member 15 is not limited to a push rod and a nitrogen gas spring, it can also be other driving elements, for example, a nitrogen gas spring is used to replace the push rod of this embodiment, and a stepping Motor or air cylinder replace the nitrogen gas spring of present embodiment.

The upper mold 3 includes an upper mold base 31 and an upper movable block 33 . The upper mold base 31 is fixed on the installation surface 111 of the upper machine platform 11 . The upper mold base 31 includes a mold surface 311 away from the installation surface 111 , a receiving through hole 313 for accommodating the upper movable block 33 , and two protruding guide blocks 315 located on both sides of the mold surface 311 . The mold surface 311 includes a molding surface 3111 and a blanking surface 3113 respectively located on two sides of the molding surface 3111 , and two ends of the molding surface 3111 are respectively connected to the corresponding blanking surfaces 3113 . The blank holder profile 3113 is a plane parallel to the installation surface 111 of the upper machine 11 , and it is used to fix the blank 2 together with the blank holder 7 . The shape of the molding surface 3111 is the same as that of the corresponding part of the part to be processed. The receiving through hole 313 runs through the molding surface 3111 and the upper mold base 31 , and extends to the installation surface 111 of the upper machine table 11 . The mounting surface 111 has a second spacer 336 extending in the receiving through hole 313 along the direction perpendicular to the mounting surface 111; parallel. The first spacer 154 between the second nitrogen gas spring 155 and the upper machine platform 11 is arranged in a direction parallel to the installation surface 111 at the opening of the receiving through hole 313 close to the installation surface 111 for supporting the second spacer 336 . A guiding wear-resistant plate 3131 is provided in the receiving through hole 313 for guiding the movement of the upper movable block 33 . The upper movable block 33 includes a fixed end 331 fixed to the second nitrogen gas spring 155 and a contact end 333 for contacting the blank 2 . The upper movable block 33 can move along the guide wear plate 3131 in the receiving through hole 313 under the action of the second nitrogen gas spring 155 . The fixed end 331 of the upper movable block 33 is also fixed with a bottom cushion block 335 . When the upper movable block 33 moves upwards to the bottom under the action of the second nitrogen gas spring 155 , the bottom cushion block 335 can abut against the second cushion block 336 to limit the movement stroke of the second nitrogen gas spring 155 . In addition, in this embodiment, a stop block 317 protrudes above the opening of the lower end of the inner wall of the accommodating through hole 313 , and a protrusion that can stop at the stop block 317 is protruded on the peripheral surface of the fixed end 331 of the upper movable block 33 . edge 334 to prevent the upper movable block 33 from slipping out of the receiving through hole 313 through a sliding transition in the receiving through hole 313 .

The lower mold 5 includes a lower mold base 51 , a lower movable block 53 and a mold core 55 . The lower mold base 51 is fixed on the installation surface 131 of the lower machine table 13 , and the lower mold base 51 is provided with a through hole 511 for the push rod 151 to freely pass through. A bottom pad 513 for abutting against the blank holder 7 is also fixed on the lower mold base 51 . When the blank holder 7 moves down to the bottom under the action of the push rod 151 , the bottom cushion block 513 can abut against the bottom of the blank holder 7 to limit the movement stroke of the push rod 151 . Die core 55 is fixed on the lower mold base 51. The end surface of the mold core 55 away from the mounting surface 131 is provided with a mold core surface 551 having the same shape as the corresponding part of the part to be processed. The mold core 55 is provided with an installation through hole 553 that runs through the mold core surface 551 and the lower mold base 51 and extends to the installation surface 131 of the lower machine platform 13 . A guide wear plate 5531 is provided in the installation through hole 553 for guiding the movement of the lower movable block 53 . The lower movable block 53 is installed in the installation through hole 553 , and it includes a fixed end 531 fixed to the first nitrogen gas spring 153 and a contact end 533 for pressing the blank 2 . The lower movable block 53 can move along the guide wear-resistant plate 5531 in the installation through hole 553 under the action of the first nitrogen gas spring 153 . In addition, the fixed end 531 of the lower movable block 53 is also fixed with a bottom cushion block 535 . The first spacer 154 between the first nitrogen spring 153 and the lower machine platform 13 is arranged on the opening of the installation through hole 553 near the installation through hole 553 along the direction parallel to the installation surface 131, and the first spacer 154 also A second spacer 536 is fixedly provided. The bottom cushion block 535 can abut against the second cushion block 536 when the lower movable block 53 moves downward to the bottom, so as to limit the movement stroke of the first nitrogen gas spring 153 .

The blank holder 7 includes a bottom plate 71 and a main body 73 protruding upward from an edge of the bottom plate 71 close to the core 55 . The blank holder 7 defines a through hole 75 penetrating through the bottom plate 71 and the main body 73 . The blank holder 7 is sheathed on the mold core 55 through the through hole 75 , and the bottom plate 71 of the blank holder 7 is fixed on the push rod 151 . A guide wear-resistant plate 77 is provided between the inner wall of the through hole 75 and the outer peripheral surface of the mold core 55. Under the action of the push rod 151, the blank holder 7 slides up and down along the guide wear-resistant plate 77 relative to the mold core 55 .

The end surface of the main body 73 of the blank holder 7 away from the bottom plate 71 is a stepped end surface, and the stepped end surface includes a supporting profile 731 corresponding to the blanking profile 3113 of the upper mold base 31 and a mounting platform that is recessed downward relative to the supporting profile 731 733. Beads (not shown) facing the mold core 55 can be provided on the supporting surface 731 to control the speed at which the blank 2 flows into the mold core surface 551 during the drawing process. A balance pad 735 is fixed on the installation table 733, and the balance pad 735 is used to control the gap between the upper die base 31 and the blank holder 7, so as to control the speed at which the blank 2 flows into the mold core surface 551 during the drawing process. The outer peripheral surface of the main body 73 is fixed with a guiding wear-resistant plate 737 to guide the movement between the blank holder 7 and the protruding guide block 315 of the upper die base 31 .

Please refer to Fig. 2 to Fig. 6, and use the drawing die of the present invention to draw the blank 2 into the parts to be processed. The specific steps are as follows:

The first step is to open the mold and place the blank 2; specifically: use the motor to drive the upper platform 11 to move away from the lower platform 13 (upward movement), and the upper mold base 31 moves upward together with the upper platform 11. Under the action of the second nitrogen gas spring 155 , the upper movable block 33 moves along the guide wear-resistant plate 3131 in the receiving through hole 313 in a direction away from the upper machine platform 11 to the maximum stroke of the second nitrogen gas spring 155 . Under the action of the push rod 151, the blank holder 7 moves to the maximum stroke of the push rod 151 along the guide wear plate 77 away from the lower machine platform 13 (the blank holder 7 is at the first position at this time). Under the action of the first nitrogen gas spring 153, the lower movable block 53 moves to the maximum stroke of the first nitrogen gas spring 153 along the guide wear-resistant plate 5531 in the installation through hole 553 to the maximum stroke of the first nitrogen gas spring 153. The end face of the contact end 533 of 53 is flush with the support profile 731 of the blank holder 7 . The blank 2 is placed flat on the support profile 731 and the end surface of the contact end 533 . Adjust the first nitrogen gas spring 153 and the second nitrogen gas spring 155 so that the initial pressure of the upper movable block 33 is greater than the supporting force of the lower movable block 53 .

The second step is mold clamping; specifically: drive the upper machine platform 11 to move toward the direction close to the lower machine platform 13 (downward motion) with a motor. The upper mold base 31 and the upper movable block 33 move downward together with the upper machine table 11 until the blank holder surface 3113 of the upper mold base 31 is in contact with the blank 2, and the blank 2 is pressed to the support profile 731 of the blank holder 7 Between the blanking surface 3113 of the upper die base 31. At this time, the upper mold base 31 is in contact with the balance block 735 of the blank holder 7 . The inner wall surface of the protruding guide block 315 of the upper die 3 is sheathed outside the main body 73 of the blank holder 7 , and can move up and down along the guide wear plate 737 of the blank holder 7 . The upper movable block 33 keeps a certain distance from the blank 2, and the distance is determined according to the pre-tensioning stiffness of the blank 2. The contact end 533 of the lower movable block 53 abuts against the blank 2 , and the lower movable block 53 is kept stationary under the support of the first nitrogen gas spring 153 .

The third step is to carry out pre-drawing; specifically: the lower movable block 53 remains still under the support of the first nitrogen spring 153; Support the profile 731 to press the blank 2 tightly; the upper mold base 31 and the upper movable block 33 continue to move downward together with the upper machine platform 11, and the blank holder 7 also moves downward together with the upper machine platform 11 to make the lower movable The block 53 moves upward relative to the blank 2 ; during this process, the blank 2 is stretched under the support of the contact end 533 of the lower movable block 53 . When the upper movable block 33 moves down to contact with the blank 2 (at this time, the blank holder 7 is in the second position), the pre-drawing is completed and the normal drawing state is entered. In this process, the contact area between the blank 2 and the contact end 533 of the lower movable block 53 can be kept at a suitable rigidity by adjusting the moving speed of the upper machine table 11, and by adjusting the pressing force between the lower movable block 53 and the blank 2 Size, can effectively control cracking and wrinkling.

The fourth step is to carry out drawing forming; specifically: in the first stage of drawing forming, the upper mold base 31 , the upper movable block 33 and the blank holder 7 continue to move downward together with the upper machine table 11 . The upper movable block 33 pushes down the movable block 53 under the action of the upper die base 31, so that the lower movable block 53 moves downward due to being pressed, while the upper movable block 33 is pressed but is still relative to the upper die base 31. Until the end pad 535 is against the second pad 536, at this moment, the first nitrogen gas spring 153 is in the position with the smallest stroke and no longer moves downward, the end surface of the contact end 533 of the lower movable block 53 and the surface of the mold core surface 551 The highest point is even, and the blank 2 enters the second stage of drawing forming, and begins to carry out normal drawing forming.

In the second stage of drawing forming, the upper die base 31, upper movable block 33 and blank holder 7 continue to move downward together with the upper machine platform 11, and the upper movable block 33 moves upward relative to the upper die base 31 due to pressure. Until the bottom spacer 335 is against the second spacer 336, the bottom plate 71 of the blank holder 7 is against the bottom spacer 513 (the blank holder 7 is at the third position at this moment), at this moment, the push rod 151 and the second nitrogen gas The springs 155 are all at the minimum stroke.

In the normal drawing process, the blank 2 is formed under the action of the mold core surface 551, the forming surface 3111 of the upper mold base 31, the contact end 333 of the upper movable block 33 and the contact end 533 of the lower movable block 53 at a predetermined The speed flows into the cavity formed by the molding surface 3111 and the mold core surface 551 to form a part blank.

The fifth step is to open the mold and take out the blank of the processed part; specifically, the upper machine table 11 is driven upward by a motor, and the upper mold base 31 and the upper movable block 33 move upward together with the upper machine table 11. The upper movable block 33 resets to the maximum stroke of the second nitrogen gas spring 155 under the action of the second nitrogen gas spring 155; the blank holder 7 resets to the maximum stroke of the push rod 151 under the action of the push rod 151; the lower movable block 53 Under the action of the first nitrogen gas spring 153, it returns to the maximum stroke of the first nitrogen gas spring 153, and the part blank that has been drawn and formed is pushed out to complete a drawing process.

It can be seen from the above description that the drawing die of the present invention adds a lower movable block 53 to the lower die base 51, so that the blank 2 is pre-stretched through the lower movable block 53 until it reaches the pre-designed rigidity, and the upper die The upper movable block 33 of 3 only participates in the drawing, which ensures the rigidity of the blank 2 in the drawing process. Moreover, the lower movable block 53 has a supporting effect on the blank 2, which can effectively prevent the center of the blank 2 from being too recessed into the cavity due to the weight of the blank 2 when stamping large parts, and can also prevent the blank from adhering to the mold in a large area. The surface of the kernel increases the probability of wrinkling, cracking and insufficient rigidity when the cover is formed. In addition, the upper movable block 33 in the present invention acts as a jacking material, which can prevent parts from being stuck in the upper die 3 after stamping.

Please refer to FIG. 7 , in another embodiment of the present invention, the upper mold 3 includes an upper mold base 31 without an upper movable block 33 . The upper mold base 31 is provided with a third nitrogen gas spring 351 on one of the protruding guide blocks 315 . It can be understood that in the present invention, the third nitrogen gas spring 351 can be replaced by power elements such as servo motors and cylinders. The die core 55 of the lower die 5 and the main body 73 of the blank holder 7 are provided with a mounting hole 573 that runs through the die core 55 and the blank holder 7 transversely, and the mounting hole 573 communicates with the vertical mounting through hole 553 of the lower die 5 , and the centerline of the installation hole 573 is perpendicular to the centerline of the installation through hole 553 . The lower movable block 53 includes a main body 91 transversely penetrating through the installation hole 573 and an abutting body 93 slidably installed in the installation through hole 553 , and the abutting body 93 is vertically extended from the main body 91 . The main body 91 can move up and down in the installation hole 573 driven by the first nitrogen gas spring 153 . The upper part of the first end of the body 91 exposed outside the installation hole 573 is fixedly connected with the third nitrogen gas spring 351 , and the body 91 can be driven to move upward or downward by operating the third nitrogen gas spring 351 and the first nitrogen gas spring 153 . A mounting boss 911 protrudes from the upper portion of the second end of the body 91 exposed outside the mounting hole 573 . The mounting boss 911 is provided with a balance gasket 913 which can be abutted against the upper mold base 31 . Bottom pads 517 are respectively provided at the lower parts of the first end and the second end of the body 91 .

The concrete steps of utilizing the drawing die processing part of the embodiment shown in Fig. 7 are as follows:

The first step is to open the mold and place the blank (not shown in the figure); specifically: use the motor to drive the upper machine table to drive the upper mold base 31 to move upward; at the same time, use the first nitrogen spring 153, the third nitrogen spring 351 and the push rod 151 The driving body 91 and the blank holder 7 passing through the body 91 move upward perpendicular to the installation hole 573 until the top surface of the abutting body 93 is flush with the supporting surface 731 of the blank holder 7 and exceeds the mold core 55. The highest point of the bead profile 551 (at this time, the blank holder 7 is in the first position); At this time, the protruding guide block 315 of the upper mold base 31 provided with the third nitrogen gas spring 351 is away from the elastic washer 913; and the first nitrogen gas spring 153 and the third nitrogen gas spring 351 are at the maximum stroke.

The second step is to close the mold; specifically: use the motor to drive the upper machine table to drive the upper mold base 31 to move downward until the blank holder surface 3113 of the upper mold base 31 is in contact with the blank, and press the blank to the edge of the blank holder ring 7 between the supporting profile 731 and the crimping profile 3113 of the upper mold base 31 . At this time, the upper mold base 31 is in contact with the balance pad 735 of the blank holder 7 and the balance pad 913 of the lower movable block 53; the third nitrogen gas spring 351 is compressed.

The third step is to carry out pre-drawing; specifically: the upper die base 31 and the blank holder 7 continue to move downward, while the lower movable block 53 remains still under the support of the first nitrogen gas spring 153, so that the lower movable block 53 moves upward relative to the blank 2, so that the blank 2 is stretched under the support of the abutting body 93 of the lower movable block 53, until the upper die base 31 and the blank holder 7 move to the stroke designed for pre-stretching ( At this time, the blank holder 7 is in the second position), at this time, the pre-drawing is finished and the normal drawing forming state is entered.

The fourth step is to carry out drawing forming; specifically: the upper mold base 31 and the blank holder 7 continue to move downward together with the upper machine table 11, when the forming surface 3111 and the blank above the abutting body 93 of the lower movable block 53 After contact, push the lower movable block 53 to move downward until the end surface of the abutting body 93 of the lower movable block 53 is flush with the highest point of the mold core surface 551, and the blank holder 7 and the body 91 are respectively connected to the bottom cushion block 513. Offset with 517 (at this moment, blank holder ring 7 is in the third position). During this process, the blank 2 flows into the molding surface 3111 and the mold core at a predetermined speed under the joint action of the mold core surface 551, the molding surface 3111 of the upper mold base 31 and the abutting body 93 of the lower movable block 53. The part blank is formed in the cavity formed by the surface 551.

The fifth step is to open the mold and take out the blank of the processed part; specifically, the motor drives the upper machine platform 11 to move upward, and the upper mold base 31 moves upward together with the upper machine platform 11 . The blank holder 7 is reset to the first position of the blank holder 7 under the action of the push rod 151; the lower movable block 53 is reset to the first nitrogen spring 153 and the third nitrogen spring 351 under the action of the first nitrogen spring 153 and the third nitrogen spring 351. At the maximum stroke of the third nitrogen gas spring 351, the part blank that has been drawn and formed is pushed out to complete a drawing process.

It should be noted that, in this embodiment, the first nitrogen gas spring 153 can be replaced by driving parts such as driving motors and cylinders. Among them, the lower movable block 53 can adopt the same structure as the embodiment shown in Figs. Embodiment same structure. In the embodiment shown in Fig. 7, the lower movable block 53 can also play the role of pre-stretching the blank 2 and supporting and lifting the blank 2, thereby avoiding the insufficient rigidity of the blank 2 during drawing forming question.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, may use the technical content disclosed above to make some changes or modify them into equivalent embodiments with equivalent changes, but as long as they do not depart from the technical solution of the present invention, the Technical Essence Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solution of the present invention.

Claims (10)

1. a kind of drawing die, including upper mould (3), lower mould (5) and blank holder (7)；

, with the shaping type face (3111) for forming part, the lower mould (5) is including die shoe (51) and admittedly for the upper mould (3) Due to the die (55) of the die shoe (51), the die (55) is with the die corresponding with the shaping type face (3111) Type face (551), it is characterised in that：The blank holder (7) moves up and down during drawing and moulding relative to the die (55), The blank (2) of part is located between the blank holder (7) and the upper mould (2), and by the blank holder (7) with it is described The change of relative position between shaping type face (3111) and the die type face (551), using the shaping type face (3111) and The die type face (551) carries out drawing to blank (2)；

The lower mould (5) be provided with through die type face (551) installation through-hole (553) and can be in the installation through-hole (553) The lower movable block (53) of interior movement；The lower movable block (53) contacts with blank (2) always during drawing and moulding, and One of them stage during drawing and moulding carries out pre- drawing to blank (2).

2. drawing die as claimed in claim 1, it is characterised in that：Work of the blank holder (7) in the drawing die During be sequentially located at first position, the second place and the 3rd position；When the blank holder (7) is positioned at the first position, Blank (2) is located between the blank holder (7) and the upper mould (3), and is contacted with the lower movable block (53)；When described During blank holder (7) is moved from the first position to the second place, the lower movable block (53) supports blank, right Blank carries out pre- drawing；During the blank holder (7) is moved from the second place to the 3rd position, it is described under Movable block (53) is moved downward, and the die type face (551) and the shaping type face (3111) are formally drawn blank (2) Prolong.

3. drawing die as claimed in claim 2, it is characterised in that：The upper mould (3) is including upper bolster (31) and upper activity Block (33), the upper bolster (31) is provided with the receiving opening (313) through the shaping type face (3111), the upper movable block (33) it is contained in the receiving opening (313) and can moves in the receiving opening (313), the upper movable block (33) exists The blank holder (7) positioned at the first position when away from blank (2), in the blank holder (7) from the first position to institute State during the second place is moved and move closer to blank (2), in the blank holder (7) from the second place to the described 3rd Then and relatively described upper bolster (31) is moved upwards position first compresses blank (2) during moving,.

4. drawing die as claimed in claim 3, it is characterised in that：The initial pressure of the upper movable block (33) is more than described The support force of lower movable block (53), during the blank holder (7) is moved from the second place to the 3rd position, Then and relatively described upper bolster (31) is transported upwards lower movable block (53) described in the upper movable block (33) elder generation top pressure is moved downward, It is dynamic.

5. drawing die as claimed in claim 3, it is characterised in that：The drawing die also includes：With the lower movable block (53) the second nitrogen spring (155), the Yi Jiyu that connected the first nitrogen spring (153) is connected with the upper movable block (33) The connected push rod (151) of the blank holder (7).

6. drawing die as claimed in claim 5, it is characterised in that：The lower movable block (53) and first nitrogen spring (153) between, between the upper movable block (33) and second nitrogen spring (155) and the blank holder (7) with it is described Cushion block (535,335,513) on earth are provided between die shoe (51).

7. drawing die as claimed in claim 3, it is characterised in that：Between the blank holder (7) and the die (55), institute State between blank holder (7) and the upper bolster (31), the hole wall of the lower movable block (53) and the installation through-hole (553) it Between and the upper movable block (33) and the hole wall of the receiving opening (313) between be provided with guiding wearing plate (77,737, 5531、3131)。

8. drawing die as claimed in claim 1, it is characterised in that：The blank holder (7) is included for carrying blank (2) Support type face (731) and installation table top (733) from relative support type face (731) to lower recess, installation table top (733) with Balance cushion block (735) is provided between the upper mould (3).

9. the method that the drawing die described in a kind of utilization claim 1 processes part, it is characterised in that it includes：

Move on mould (3) in order, drawing die is opened；

Making and moved on blank holder (7) and lower movable block (53), and make the top surface of lower movable block (53) and the support type face of blank holder (7) (731) it is concordant；

Blank (2) is positioned on the support type face (731) and lower movable block (53) of blank holder (7)；

Mould (3) is moved down in order, and blank (2) is located between blank holder (7) and upper mould (3)；

Make blank holder (7) and upper mould (3) move down, blank (2) is pre-stretched using lower movable block (53)；

Make blank holder (7) and upper mould (3) continue to move down, and make the relative die (55) of lower movable block (53) move down, using die type Face (551) and shaping type face (3111) carry out formal drawing to blank (2).

10. the method for processing part as claimed in claim 9, it is characterised in that：The upper mould (3) including upper bolster (31) and Upper movable block (33), the upper bolster (31) is provided with the receiving opening (313) through the shaping type face (3111), the upper work Motion block (33) is contained in the receiving opening (313) and can move in the receiving opening (313), the processing part Method also includes：

Movable block (33) is moved down relative to upper bolster (31) in order；

Movable block (33) is moved down together with upper bolster (31) in order, by blank (2) be located in blank holder (7) and upper bolster (31) it Between；

Movable block (33) continues to move down together with upper bolster (31) in order, until upper movable block (33) is contacted with blank (2)；

Movable block (33) is further moved down together with upper bolster (31) in order, and makes movable block (53) under upper movable block (33) top pressure Move down with respect to die (55)；

Movable block (33) is further moved down together with upper bolster (31) in order, and using upper movable block (33) blank (2) is supported, and Move on the relative upper bolster (31) of movable block (33) in order.