JP7155578B2 - Processing device and method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drawing processing apparatus and method.

Draw forming is known as one of press working. A press machine is used in draw forming. A typical stamping apparatus includes a punch and a die as a mold. The punch or die is pressed against the workpiece, which is a plate material, when drawing is started, thereby giving the blank a concave-convex shape corresponding to the punch and die.

However, when the punch or die is pressed against the blank, the blank may wrinkle. The presence or absence of wrinkles is an important factor for processing quality. Therefore, in order to prevent wrinkling, a punch is pressed against the blank while the blank is held by a die and a wrinkle holding plate (blank holder).

Therefore, in order to reduce wrinkles, for example, Patent Document 1 provides a mechanism for controlling the wrinkle pressing force applied from the blank holder to the workpiece to an optimum value.

JP 2009-195956 A

On the other hand, in electric vehicles, for example, body parts such as floor panels may have to be uneven in shape so as not to interfere with components such as batteries. Therefore, the shape of the body parts becomes complicated. Also, depending on the size of the component parts, the depth of drawing of the body parts may have to be formed deeper.

However, when forming a complicated concave-convex shape or deep drawing with a conventional press working apparatus, even if a blank holder is used, it may not be possible to sufficiently suppress wrinkles. Therefore, the shape of the body part to be molded may have to be changed.

In order to solve the above problems, the present invention provides a processing apparatus configured as follows.

First, the invention according to claim 1 of the present application is a processing apparatus for deep drawing a blank. The processing apparatus has an upper structure and a lower structure that face each other in the vertical direction, and an elevating mechanism that brings at least one of the upper structure and the lower structure closer to the other. Either the upper structure or the lower structure has a die. Either the upper structure or the lower structure has a punch and a blank holder. When the punch and the blank holder are viewed in the vertical direction, the blank holder surrounds the entire circumference of the punch. The blank holder is configured to sandwich the blank positioned between the upper structure and the lower structure. The blank holder includes a first blank holder portion surrounding the entire circumference of the punch and a second blank holder portion arranged to fill a region between the first blank holder portion and the punch. have. The punch has a first draw forming portion that forms a first draw shape in the blank. The second blank holder part has a second draw forming part for forming a second draw shape in the blank. The die has a recess that cooperates with the second draw forming portion to form the second draw shape.

Next, the invention according to claim 2 is characterized in that the die has a depression that forms the first drawing shape in cooperation with the first drawing forming part of the punch. 1. The processing apparatus according to 1.

Further, the invention according to claim 3 is characterized in that the second blank holder part surrounds the entire circumference of the punch when viewed in the vertical direction. is a processing device.

Further, the invention according to claim 4 is the processing apparatus according to any one of claims 1 to 3, wherein the second blank holder part has a non-drawing shape.

In the invention according to claim 5, the die, the punch, the first blank holder part, and the second blank holder part are arranged such that the distance between the die and the first blank holder part is D1. , where D2 is the distance between the die and the second blank holder portion, and D3 is the distance between the die and the punch, D1 to D3 have a relationship of D1<D2<D3. , the processing apparatus according to any one of claims 1 to 4. When the upper structure and the lower structure are brought close to each other in the processing apparatus, first, the first blank holder section holds the blank together with the die, and then the second blank holder section holds the blank together with the die. Sandwich and finally the punch is configured to sandwich the blank with the die.

Finally, in the invention according to claim 6, the punch is fixed to a base, the first blank holder part is supported by the base via a first cushion, and the second blank holder part is supported by the base. is supported by the base through a second cushion, the first cushion is extendable and retractable between the extended position and the retracted position, and the second cushion is extended 6. A processing device according to claim 5, characterized in that it is telescopic between a position and a contracted position.

Moreover, in order to solve the above problems, the present invention provides the following press working method.

The invention according to claim 7 is a processing method. The above processing method includes a die, a punch arranged in the center when viewed from the die, a first blank holder portion surrounding the punch when viewed from the die, and a blank holder portion which surrounds the punch when viewed from the die. a second blank holder part positioned between the punch and the first blank holder part, wherein the punch, the first blank holder part and the second blank holder are positioned with respect to the die; a method of drawing a blank disposed between said die and said punch, said first blank holder part and said second blank holder part by bringing the parts closer together. The processing method includes a step 1 of sandwiching and holding the blank between the die and the first blank holder, and following step 1, sandwiching the blank between the die and the second blank holder. It is characterized by comprising a step 2 of forming a second drawing shape and a step 3 of pressing the punch against the blank to form the first drawing shape following the step 2.

According to the invention of claim 1 of the present application, it is possible to provide a processing apparatus capable of producing products having complex concave-convex shapes and deep drawing, such as body parts for electric vehicles, with extremely few wrinkles. As a result, the quality of the product with the aperture is significantly higher than before.

In addition, according to the seventh aspect of the present invention, it is possible to provide a processing method for producing products having complex concave-convex shapes and deep drawing, such as body parts for electric vehicles, with extremely few wrinkles. As a result, the quality of the product with the aperture is significantly higher than before.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view which shows schematic structure of the processing apparatus which concerns on embodiment of this invention. 2 is a top plan view of the lower structure shown in FIG. 1; FIG. It is a longitudinal cross-sectional view of a processing apparatus showing a state in which a blank is sandwiched between a first blank holder and dies. FIG. 4 is a plan view of the blank and the lower structure showing the drawing shape formed in the blank in a state where the blank is sandwiched between the first and second blank holders and the dies; FIG. 4 is a vertical cross-sectional view of the processing apparatus showing a state in which a blank is sandwiched between first and second blank holders and dies; FIG. 4 is a plan view of the blank and the lower structure showing the drawing shape formed on the blank while the blank is sandwiched between the punch, the first and second blank holders, and the die. FIG. 4 is a vertical cross-sectional view of the processing apparatus showing a state in which a blank is sandwiched between a punch, first and second blank holders, and dies; It is a top view of the lower structure in the processing apparatus of a comparative example. It is a longitudinal cross-sectional view of the processing apparatus of a comparative example. FIG. 10 is a plan view of a blank processed by a processing apparatus of a comparative example;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, a drawing apparatus 100 according to an embodiment of the present invention generally has an upper structure 10 and a lower structure 12 arranged below the upper structure 10 . The superstructure 10 has a die 14 . Substructure 12 has punch 16 and blank holder 18 .

As shown in FIG. 2, the punch 16 has a first draw forming portion 20 having a draw shape in the upper end region facing the die 14 . In an embodiment, the first drawformer 20 has a deep drawform 22 in the form of a high plateau indicated by high density halftone dots in FIG. 2 and a low plateau in the form of medium to high density halftone dots in FIG. It has a shallow drawing shape 24 . The deep draw profile 22 has a flat profile portion 26 and an inclined portion 28 that tapers outward from the flat profile portion 26 . The shallow draw profile 24 is located outside the deep draw profile 22 and has a flat profile portion 30 and an inclined portion 32 that tapers outwardly from the flat profile portion 30 .

As shown in FIGS. 1 and 2, the blank holder 18 includes a first blank holder portion (outer blank holder portion) 34 arranged to surround the punch 16 when viewed from above (the die 14); It has a second blank holder part (inner blank holder part) 38 that fills the area 36 between the punch 16 and the first blank holder part 34 when viewed from above (the die 14). In the embodiment, the second blank holder part 38 surrounds the punch 16 all around, but it does not have to surround the punch 16 all around.

As shown in FIG. 2 , the first blank holder part 34 has a flat surface (blank holding surface) 40 in a region facing the die 14 . The second blank holder part 38 has a second draw forming part 42 having a draw shape. In an embodiment, the second draw-former 42 has a generally C-shape when viewed from above (the die 14), and has a low-plateau-shaped draw-shape 44 indicated by medium and low-density halftone dots in FIG. have The aperture shape 44 has a flat shape portion 46 and an inclined portion 48 that gradually lowers outward from the flat shape portion 46 . In an embodiment, the second iris forming portion 42 of the second blank holder portion 38 is positioned to block the opening of the generally C-shaped plateau and has a flat, non-iris shape indicated by low density halftone dots in FIG. (blank clamping surface) 50;

As shown, the second draw shape 44 of the second blank holder portion 38 may be provided with one or more steps 52,54.

Returning to FIG. 1, both the punch 16 and the blank holder 18 (the first blank holder portion 34 and the second blank holder portion 38) are supported by the base 60. As shown in FIG. The base 60 is fixed to the floor 62 or the like of the building. The punch 16 is fixed to the base 60 . The first blank holder portion 34 is supported by the base 60 via a first cushion 64 . The second blank holder portion 38 is supported by the base 60 via a second cushion 66 . Pneumatic or hydraulic cylinders or springs can be used for the first cushion 64 and the second cushion 66 .

As shown in FIG. 1, on the lower surface of the die 14, recesses (recesses 68) having shapes corresponding to the projections (the deep drawing shape 22 and the shallow drawing shape 24) of the first drawing forming portion 20 of the punch 16, A concave portion (depression 70) corresponding to the convex portion (diaphragm shape 44) of the second drawing forming portion 42 in the second blank holder portion 38 and a flat surface 72 surrounding the circumference of these depressions 68 and 70 are formed. there is The projections (deep drawing shape 22, shallow drawing shape 24, drawing shape 44) of the punch 16 and the second blank holder part 38 and the recesses (recesses 68, 70) of the die 14 are, as will be described later, these projections and projections. When a blank having a predetermined thickness is sandwiched between the recesses, the lower surface and the upper surface of the blank are provided with corresponding convex and concave shapes, respectively.

The height of the first blank holder part 34, the second blank holder part 38 and the punch 16, in other words the first blank holder part 34, the second blank holder part 38 and the punch 16 facing the die 14 The minimum distances D1, D2, D3 between the portions 74, 76, 78 and their corresponding die portions 80, 82, 84 are such that the first blank holder portion 34 and the second blank holder portion 38 are not loaded. It is determined so as to satisfy the relationship D1<D2<D3 when the first cushion 64 and the second cushion 66 are not stretched (when the first cushion 64 and the second cushion 66 are stretched). Thereby, when the die 14 descends, the first blank holder part 34 is first positioned with respect to the die 14, then the second blank holder part 38 is positioned with respect to the die, and finally the punch 16 is positioned with respect to the die 14. positioned relative to

The die 14 is held by a die holder (not shown). The die holder is connected to a pneumatic or hydraulic lifting device 86 . Therefore, the die 14 is configured to move between the raised position shown in FIG. 1 and the lowered position shown in FIG.

The operation of the drawing apparatus 100 having the above configuration will be described. Prior to processing, the die 14 of the upper structure 10 is in the raised position shown in FIG. 1 and the first cushion 64 and the second cushion 66 of the lower structure 12 are in an extended condition. In this state, blank 88 is placed between upper structure 10 and lower structure 12 .

From this state, the elevating device 86 is driven to lower the die 14 . In this process, as shown in FIG. 3, the lowest flat surface 72 (die portion 80) of the die 14 first hits the flat surface 40 of the first blank holder portion 34 (die facing portion 74). As a result, the outer periphery of the blank 88 is held between the die 14 and the first blank holder portion 34 .

When the die 14 is further lowered from this state, the first cushion 64 contracts as the die 14 descends, and the blank holding force (sandwiching force) between the die 14 and the first blank holder portion 34 increases. go.

As the die 14 is further lowered, the draw shape 44 of the second blank holder portion 38 hits the blank 88 . At this point, the non-drawn shape 50 of the second blank holder portion 38 has not yet contacted the blank 88 .

When the die 14 is further lowered from this state, the drawn shape 44 of the second blank holder portion 38 is pressed against the blank 88, and the second drawn shape 44' (see FIG. will be given to During the descent of the die 14, force is transmitted from the blank 88 to the second blank holder portion 38, causing the second cushion 66 to shrink. At this time, the blank portion around the blank portion to be processed (deformed) by the second blank holder portion 38 is firmly held by the die 14 and the first blank holder portion 34 . Therefore, during the application of the second drawing shape 44' to the blank 88, no wrinkling or deformation occurs in the peripheral blank portion.

After that, as shown in FIG. 5, when the drawing shape 44 of the second blank holder part 38 is completely accommodated in the corresponding recess 70 of the die 14, the non-drawing shape 50 of the second blank holder part 38 becomes the blank. It hits the corresponding portion of die 14 via 88 .

After that, when the die 14 descends further, the first cushion 64 and the second cushion 66 contract according to the descent of the die 14, and the blank holding force (sandwiching force) by the die 14 and the blank holder 18 increases.

As the die 14 is further lowered, the deep draw shape 22 and the shallow draw shape 24 of the punch 16 are sequentially pressed against the blank 88, and the first draw shapes 22', 24' corresponding to the deep draw shape 22 and the shallow draw shape 24 are formed. (see FIG. 6) is applied to the blank 88. As shown in FIG. At this time, as shown in FIG. 7, the blank portion around the blank portion to be processed (deformed) by the punch 16 is firmly held by the die 14 and the second blank holder portion 38 . Therefore, during the application of the first drawing shape 22', 24' to the blank 88, no wrinkles or deformations occur in the peripherally located blank portions.

Thus, according to the drawing apparatus according to the embodiment, it is possible to give a blank a deep drawing shape, a shallow drawing shape, and a drawing shape with an intermediate depth therebetween. In addition, it is of course possible to completely surround a deep drawn shape with a shallower drawn shape. It is also possible to arrange a part of the deep drawing shape on the outer edge. Therefore, complex shapes can be imparted to the blank without wrinkling.

For comparison, numerical analysis was performed on the occurrence of "wrinkles" during drawing using a blank holder consisting of one blank holder portion. As shown in FIG. 8, the lower structure of the drawing apparatus used for the analysis consisted of a punch 16 and a blank holder 18 surrounding it (one blank holder portion). The drawing applied to the blank includes a deep drawing shape, a shallow drawing shape, and a medium drawing shape having an intermediate depth, and as shown in FIG. given shape. As a result of the analysis, as shown in FIG. 10, it was confirmed that wrinkles were generated in the intermediate drawing shape and the shallow drawing shape, and in particular, more wrinkles were generated in the shallow drawing shape.

In the above-described embodiment, the drawing apparatus 100 has the lower structure 12 and the upper structure 10, the lower structure 12 includes the punch 16 and the blank holder 18, and the upper structure 10 includes the die 14. Also included within the scope of the invention is a configuration in which the includes the die and the superstructure includes the punch and blank holder.

Further, in the above-described embodiment, the drawing shape 44 of the second blank holder portion 38 is substantially C-shaped, and the drawing shape 44 and a part of the punch 16 are surrounded. The drawing shape 44 may surround the punch 16 all around.

Furthermore, in the above-described embodiment, the dimples 68 having shapes corresponding to the deep drawing shape 22 and the shallow drawing shape 24 of the punch 16 are formed in the die 14. A cavity may be provided and the corresponding die portion may be machined only by pressing the deep draw feature 22, ie without sandwiching the die.

100: Drawing device 10: Upper structure 12: Lower structure 14: Die 16: Punch 18: Blank holder 20: First drawing forming part 22: Deep drawing shape 24: Shallow drawing shape 22', 24': First Aperture shape 26: Flat shape portion 28: Inclined portion 30: Flat shape portion 32: Inclined portion 34: First blank holder portion 36: Region 38: Second blank holder portion 40: Flat surface (blank clamping surface)
42: Second drawn portion 44: Drawn shape 44′: Second drawn shape 46: Flat shape portion 48: Inclined portion 50: Non-drawn shape 52, 54: Stepped portion 60: Base 62: Floor 64: First cushion 66: Second cushion 68: Indentation 70: Indentation 72: Flat surfaces 74, 76, 78: Die facing portions 80, 82, 84: Die portion 86: Elevating device 88: Blanks D1, D2, D3: distance

Claims (7)

In the processing equipment for deep drawing blanks,
The processing device has an upper structure and a lower structure that face each other in the vertical direction, and an elevating mechanism that brings at least one of the upper structure and the lower structure closer to the other,
either the upper structure or the lower structure has a die;
Either the upper structure or the lower structure has a punch and a blank holder,
The punch and the blank holder are such that the blank holder surrounds the entire periphery of the punch when viewed from the vertical direction,
The blank holder is configured to sandwich the blank arranged between the upper structure and the lower structure,
The blank holder includes a first blank holder part surrounding the entire circumference of the punch and a second blank holder part arranged to fill an area between the first blank holder part and the punch. have
The punch has a first draw forming portion that forms a first draw shape in the blank,
The second blank holder part has a second drawing forming part for forming a second drawing shape in the blank,
the die has a depression that cooperates with the second drawing forming portion to form the second drawing shape;
The processing apparatus according to claim 1, wherein the second drawing forming portion has a C-shaped drawing shape when viewed from the vertical direction. 2. The processing apparatus according to claim 1, wherein said die has a depression that cooperates with said first drawing forming portion of said punch to form said first drawing shape. 3. The processing apparatus according to claim 1, wherein the second blank holder surrounds the punch when viewed in the vertical direction. 1 to 4, wherein the second aperture forming portion has a flat non-aperture shape arranged so as to block the opening of the C-shaped aperture when viewed from the vertical direction. 4. The processing apparatus according to any one of 3. The die and the punch, the first blank holder part, and the second blank holder part are
the distance between the die and the first blank holder is D1;
the distance between the die and the second blank holder is D2;
Assuming that the distance between the die and the punch is D3,
The D1 to D3 have a relationship of D1<D2<D3,
When the upper structure and the lower structure are brought closer together, first the first blank holder part clamps the blank together with the die, then the second blank holder part clamps the blank together with the die, and finally the blank holder part clamps the blank together with the die. The processing apparatus according to any one of claims 1 to 4, wherein a punch is configured to sandwich the blank together with the die. The punch is fixed to a base,
The first blank holder part is supported by the base via a first cushion,
The second blank holder part is supported by the base via a second cushion,
the first cushion is stretchable between an extended position and a retracted position;
6. The processing apparatus according to claim 5, wherein said second cushion is telescopic between an extended position and a contracted position. dice;
A punch arranged centrally when viewed from the die, a first blank holder portion surrounding the punch when viewed from the die, and the punch and the first blank holder when viewed from the die and a second blank holder portion positioned between the
The die and the punch, the first blank holder part and the second blank are separated by bringing the punch, the first blank holder part and the second blank holder part closer to the die. A method for drawing a blank placed between holder parts, comprising:
a step 1 of sandwiching and holding the blank between the die and the first blank holder;
A step 2 of forming a second drawn shape by sandwiching the blank between the die and the second blank holder, following the step 1;
Following step 2, step 3 of pressing the punch against the blank to form a first drawing shape,
A processing method, wherein the second drawn shape has a C-shaped drawn shape when viewed from the die .

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