JP2020001061A - Creation method of raw material for press molding and creation device therefor - Google Patents

Abstract

To provide a creation method of a raw material for press molding which has plate thickness distribution.SOLUTION: A creation method of a raw material for press molding in which areas having different plate thicknesses in a longer direction are distributed comprises a tensile bending process in which a plate to be pulled out is pushed to one side in a plate thickness direction by a tool which is provided over the full width of a belt-like plate on at least one surface side of the plate, thereby forming an area in which a plate thickness of the plate is decreased. Further, a creation method of a raw material for press molding in which areas having different plate thicknesses in a width direction are distributed comprises a bending and ironing process in which a plate to be pulled out is pushed to one side in a plate thickness direction while being pinched and is bent and ironed by a tool which is so provided on a part within a width of a belt-like plate as to be opposite to both surface sides of the plate, thereby forming an area in which a plate thickness of the plate is decreased.SELECTED DRAWING: Figure 3B

Description

  The present invention relates to a method for creating a material for press forming having a thickness distribution in which the thickness differs in each region.

  Press-formed products are used for a wide variety of products, and are used not only for simple housings and panels, but also as structural members. For example, a press-formed product is also used for a vehicle body (a pillar, a chassis, and the like) of an automobile. Such a press-formed product is required to satisfy contradictory characteristics (light weight, strength, rigidity, etc.) at a high level.

  For this reason, materials having different plate thicknesses are used depending on parts (regions). Specifically, a tailored blank steel plate obtained by welding a plurality of steel plates having different thicknesses, and a tailored rolled blank steel plate whose longitudinal thickness is changed by rolling are used.

JP 2015-15073 A

Iron and Steel 66th Year (1980) Issue 5 P110-116

  However, a tailored blank steel plate is expensive, and the material properties change between a welded portion and a non-welded portion. In order to manufacture a tailor rolled blank steel sheet, a rolling device capable of applying a large pressing force is required.

  In addition, Non-Patent Document 1 describes a rolled deformed cross-section plate, but the target is a copper (alloy) plate used in electronic devices and the like. Patent Document 1 proposes a method in which a sheet material is bent and stretched and bent back by a plurality of rolls to obtain a preformed material having a desired shape. However, this method is not a method of creating a plate-shaped material in the first place, but merely reduces the thickness of the central portion of the preform.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a new creation method and the like for obtaining a press forming material having a thickness distribution.

  The inventor of the present invention has made intensive studies to solve this problem, and as a result, unlike conventional rolling and the like, the thickness of a sheet material has been changed in a specific direction by performing plastic working such as tension bending or bending and ironing ( In other words, a press forming material having a plate thickness distribution was successfully obtained with a relatively small processing force. By developing these results, the present invention described below has been completed.

《Creation method》
(1) A first aspect of the present invention is a tool disposed on at least one side of a strip-shaped plate material over the entire width of the plate material, and the drawn-out plate material is pushed into one of the thickness direction to bend the plate material. This method is a method for producing a press-forming material including a tensile bending step of forming a region where the plate thickness of the plate material is reduced, and in which regions having different plate thicknesses in the longitudinal direction are distributed.

(2) A second aspect of the present invention is a tool disposed on a part of the width of a strip-shaped plate in opposition to both sides of the plate. This is a method for producing a press-forming material including a bending and ironing step of forming a region where the thickness of the plate material is reduced by pushing and bending and ironing the plate material, and regions where the thicknesses are different in the width direction are distributed. .

(3) In the method for producing a material for press molding of the present invention (hereinafter simply referred to as a “creation method”), plastic deformation (reduction in sheet thickness) is performed by utilizing bending deformation. According to the method, it is possible to obtain a plate-shaped material in which the plate thickness changes in the longitudinal direction or the width direction (that is, has a plate thickness distribution) with a smaller working force than in the case of simply rolling or ironing.

  Further, in the case of the creation method of the present invention, the thickness reduction amount, the thickness reduction region, and the like can be widely adjusted by changing the form, movement amount (push amount, etc.), arrangement, and the like of the tool, and the form flexibility of the material that can be created. Is also big.

  In addition, by using a press-forming material (hereinafter simply referred to as “material”) having a thickness distribution according to desired characteristics, for example, a press-formed product (eg, automobile Body member).

《Creation equipment》
The present invention can also be understood as a creation device for performing the creation method described above. For example, in the case of creating a material having a thickness distribution in the longitudinal direction, the creation device of the present invention is disposed on at least one surface side of a strip-shaped plate material, and at least a cross-sectional shape of a tip side slidingly contacting the plate material is the same. It is preferred to have a uniform tool over the entire width.

  In the case of creating a material having a thickness distribution in the width direction, the creation device of the present invention includes a tool disposed on at least a part of the width of the band-shaped plate in opposition to both sides of the plate. It is suitable to be provided.

  The creation device may be grasped as a tool (die or the like) alone or as a configuration (system) including the tool. In the latter case, the creation device of the present invention may further include, for example, a pull-out unit that pulls out a strip-shaped plate material, and a pushing unit that pushes the tool in a plate thickness direction.

  The drawing means moves the plate material to which tension has been applied to one side (downstream side). The tension must be at least generated before and after the tool. The pulling-out means can be constituted by, for example, a bead or the like that slidably holds the plate material behind and a winding device that winds the plate material forward.

  The pushing means is realized by a hydraulic, electric or other actuator. When there are a plurality of tools, the pushing means may push a plurality of tools whose height (projection amount) has been adjusted at once, or may push each tool individually. The amount of pushing of the tool or the like by the pushing means or retreat is controlled by the control device according to the thickness distribution to be created.

《Other》
(1) The present invention may be a method of creating a material having a thickness distribution in both the longitudinal direction and the width direction by performing the tensile bending step and the bending and ironing step at least once. Each of those steps may be processed continuously or batch-processed. In the case of continuous treatment, a tool for performing the tension bending process and a tool for performing the bending and ironing process may be arranged in parallel. The order of each step or the order of each tool arrangement is appropriately selected.

(2) The longitudinal direction referred to in this specification is a direction in which the plate material extends. Unless otherwise specified, the longitudinal direction is the direction in which the sheet is pulled out (simply referred to as “pulling direction”) or the direction in which a tensile force is applied (simply referred to as “tension direction”). The width direction is a direction orthogonal to the longitudinal direction, and is a short direction of the plate material. The thickness direction is a direction orthogonal to the longitudinal direction and the width direction.

  For convenience of description, the longitudinal direction is appropriately defined as the X (axis) direction, the width direction is defined as the Y (axial) direction, and the plate thickness direction is defined as the Z (axial) direction. At this time, unless otherwise specified, the direction in which the plate material is pulled out (the direction from the rear side to the forward side or the direction from the upstream side to the downstream side) is defined as the positive direction of the X axis.

(3) Unless otherwise specified, “x to y” in this specification includes the lower limit x and the upper limit y. A range such as “ab” can be newly set as a new lower limit or upper limit using various numerical values or an arbitrary numerical value included in the numerical range described in this specification.

It is an example of a form of a material whose thickness is distributed in the longitudinal direction. It is a schematic diagram which shows the creation process of the material. It is a perspective view which shows an example of the creation apparatus (tool) of the raw material. It is an example of a form of a material whose thickness is distributed in the width direction. It is a schematic diagram which shows the creation process of the material. It is a perspective view which shows an example of the creation apparatus (tool) of the raw material. It is sectional drawing which shows the form regarding the width direction of the front-end | tip surface of each tool. It is an example of a form of a material whose thickness is distributed in a longitudinal direction and a width direction. It is a schematic diagram which shows the creation process of the material. It is explanatory drawing of the creation example of the raw material which distributed the thickness in the longitudinal direction. FIG. 4 is a schematic diagram showing an analysis model when a material having a thickness distribution in the width direction is created. It is a schematic diagram of the analysis example which shows a creation process. 9 is a graph showing an example of the analysis result.

  One or more components arbitrarily selected from the present specification can be added to the components of the present invention described above. The contents described in this specification appropriately apply not only to the creation method or the creation apparatus but also to the material obtained by the creation method, and may be a method-related component or a component related to an object. Which embodiment is best depends on the target, required performance, and the like.

《Plate material》
The plate material may be any of iron, aluminum, magnesium, titanium and the like. A typical example of the plate material is a steel plate. In particular, the present invention is suitable for creating a material from a high-tensile steel sheet. In addition, “-system” means that the material is a pure metal or an alloy.

  The plate material before creation is usually a flat plate having a constant plate thickness. Although there are various sizes, the thickness is usually about 0.5 to 4 mm, and more preferably about 0.8 to 3 mm.

《Creation method》
(1) The thickness of the region subjected to the tensile bending process is smaller than that before the construction. By selectively performing the tensile bending process in the longitudinal direction, a material having a varied thickness in the longitudinal direction (that is, a thickness distribution) can be obtained.

(2) The thickness of the region where the bending and ironing process has been performed is also smaller than before the construction. By selectively performing the bending and ironing process in the width direction, a material having a changed thickness in the width direction (cross section) can be obtained.

(3) In any case, the distribution of the regions having different plate thicknesses is appropriately adjusted according to the required specifications of the material. When the thickness distribution is provided in both the longitudinal direction and the width direction, each of the above-described steps may be performed at least once. There is no limitation on the order between the steps. The application of the thickness distribution may be performed only once in each step, or may be performed in a plurality of steps (that is, in multiple stages).

《Creation tools / Creation equipment》
(1) A tool that performs tensile bending of a plate material (simply referred to as a “tensile bending tool”) has, for example, a tip portion that slides on the plate material has a uniform cross-sectional shape over the entire width of the plate material. The cross-sectional shape is, for example, a circle, an ellipse, a trapezoid, or the like. In any case, the portion that comes into contact with the plate material (the so-called “shoulder”) may have a smooth curved surface (for example, a round chamfer).

(2) A pair of tools for bending and ironing a plate (hereinafter simply referred to as “bending and ironing tools”) are provided on both sides at least partially within the width of the plate. Various cross-sectional shapes can be considered for the bending and ironing tool, similarly to the tension bending tool. One of the bending and ironing tools (the side on which the plate material is pressed to bend and deform) preferably has a smooth curved surface with a shoulder in contact with the plate material. The other of the bending and ironing tools only has to press the plate between the other and perform the ironing, and the contact portion with the plate may be a smooth curved surface or a flat surface in the longitudinal direction.

  A bending assist tool may be provided adjacent to the longitudinal direction side of the bending and ironing tool in order to cause reliable bending deformation of the plate material. Further, in order to secure a desired plate thickness, a plurality of bending and ironing tools may be provided. Further, an auxiliary tool may be provided in order to form a transition region that gently connects the small thickness region and the large thickness region. For example, when creating a sheet thickness distribution in the width direction, an auxiliary tool that changes the sheet thickness in an inclined manner (extremely) while bending the sheet material may be provided.

  Further, a shaping tool for securing a desired plate thickness may be provided in a region where the plate thickness is not reduced or the plate thickness is reduced (ironed) very slightly. It is sufficient that at least one pair of such auxiliary tools and shaping tools is provided on both sides of the plate material. The arrangement position, the number of arrangements, and the arrangement order of each tool are appropriately adjusted according to a desired thickness distribution.

  The tip surface (contact surface with the plate material) of the bending and ironing tool, the auxiliary tool, or the shaping tool may be flat or inclined in the width direction. With the inclined surface, the thickness in the width direction can be changed in an inclined manner, and a sudden change in the thickness can be mitigated.

  When the step of applying the thickness distribution in the longitudinal direction (tensile bending step) and the step of applying the thickness distribution in the width direction (bending and ironing step) are performed by a single drawing of the sheet material, the above-described tension bending tool and bending and ironing tool are used. It is good to arrange in parallel in the longitudinal direction. The order of the arrangement of these tools does not matter. In addition, at least a part of each tool may have a roll shape on the tip side of the tool that comes into contact with the plate material.

《Lateral thickness distribution》
1A to 1C (together, these are simply referred to as "FIG. 1") are shown in FIGS. For example, as shown in FIG. 1A, a material P1 having a plate thickness changed in the longitudinal direction from a band-shaped plate material P0 (not shown) having a uniform initial plate thickness is formed by an upper mold U and a lower mold shown in FIGS. 1B and 1C. L can be created.

  The upper die U includes tools U0 to U4 arranged in order from the rear (upstream) side in the drawing direction of the plate material P0, and a housing Uc for holding the tools. The lower die L includes tools L0 to L4 arranged in order from the rear side in the pulling-out direction of the plate material P0, and a housing Lc holding the tools. Each of the tools U0 to U4 and each of the tools L0 to L4 are arranged to face each other in the up-down direction. In this specification, for convenience of description, the upper and lower relations are defined based on the description of each drawing. It does not limit the vertical relationship of the actual creation device.

  When creating the regions r11 and r15 in which the plate thickness is reduced, the tools over the entire width of the plate P0 are arranged as shown in FIG. 1B, and the plate P0 is subjected to tensile bending deformation. For example, the tools U1 and U3 are pushed down, and the upper surface of the tool L2 is substantially flush with the upper surfaces of the tools L0 and L4 (the lower surface of the plate P0). The other tools are separated from the plate P0. The plate material P0 that has come into contact with these tools is subjected to tensile bending to form regions r11 and r15 having a reduced thickness in the longitudinal direction.

  The region r13 in which the plate thickness is not reduced (substantially remains the initial plate thickness) is, for example, to separate the upper mold U and the lower mold L from the plate P0 as a whole or to separate the tools U1, U3 from the plate P0. Formed. In addition, the region r13 may be formed such that an interval between each of the tools U1 to U3 and each of the tools L1 to L3 is an initial plate thickness.

  The regions r12 and r14 of the material P1 are transition regions formed during the movement of each mold or each tool. The regions r12 and r14 make the change in the plate thickness in the longitudinal direction gentle.

《Thickness distribution in the width direction》
2A to 2C (together, these are simply referred to as “FIG. 2”) are shown in FIGS. 2A to 2C showing an example of creating a material having a thickness distribution in the width direction of the plate material by a bending and ironing process. For example, as shown in FIG. 2A, a raw material P2 having a thickness changed in the width direction can be created using an upper mold U and a lower mold L from a band-shaped plate material P0 (not shown) having a uniform initial plate thickness.

  As shown in FIG. 2B, the upper mold U includes tools U0, tools U11, U12, U13, tools U21, U22, U23, tools U31, 32, 33, and tools U1 arranged in order from the rear side in the drawing direction of the plate material P0. U4 and a housing (not shown) for holding the U4.

  As shown in FIG. 2B, the lower mold L has tools L0, L11, L12, L13, L21, L22, L23, L31, 32, 33, L31, L32, and L33 arranged in this order from the rear side in the drawing direction of the plate material P0. L4 and a housing (not shown) for holding the L4. The respective tools constituting the upper mold U and the lower mold L are arranged to face each other in the vertical direction. In addition, each tool can independently adjust the vertical position.

  In the case of creating the regions r21 and r25 in which the plate thickness is reduced, the tools U11, U21, U31 and the tools L11, L21, L31 (bending ironing tools) arranged in the longitudinal direction on both ends of the plate material P0 are shown in FIG. 2B. And the plate material P0 is pulled out so that the plate material P0 passes between them. At this time, the pair of tools U11 and L11, the pair of tools U21 and L21, and the pair of tools U31 and L31 are respectively displaced vertically. Further, the gap between each pair of tools may be gradually narrowed, for example, from the rear toward the front (pull-out direction). The sheet material P0 to be pulled out is bent and squeezed when passing between the tools. Thereby, plastic deformation is caused in the end region r21 (r25) of the plate material P0 with a relatively small force, and the plate thickness can be reduced.

  The region r23 where the initial plate thickness of the plate P0 is substantially maintained is such that the tools U13, U23, U33 and the tools L13, L23, L33 (shaping tools) arranged in the central longitudinal direction of the plate P0 so that bending and ironing do not occur. Are arranged as shown in the cross section C in FIG. 2B, and the plate material P0 is passed between them. Each pair of tools arranged in the vertical direction may be separated from the plate material P0, or at least the gap between the pair of tools (the gap between the tool U23 and the tool L23 in FIG. 2B) may be set as the initial thickness.

  The regions r22 and r24 of the material P2 are transition regions between regions r21 and r25 in which the plate thickness is reduced in the longitudinal direction and regions r23 in which the plate thickness is not reduced, and the change in the plate thickness in the width direction is moderated. I have. In this case, the tools U12, U22, U32 and the tools L12, L22, L32 (auxiliary tools) arranged in the longitudinal direction are shown in the cross section B in FIG. 2B, as in the case of creating the above-described regions r21, r25. And the plate material P0 is passed between them. Also at this time, each pair of adjacent tools is slightly shifted in the vertical direction. Also, the gap between each pair of tools may be gradually narrowed, for example, from the rear toward the front (pull-out direction). As a result, when the plate material P0 to be pulled out passes between the tools, it is bent and slanted in the width direction while being bent. Thus, with a relatively small force, the region r22 (r24) of the plate P0 is also plastically deformed, so that the plate thickness can be changed. Since the region r22 (r24) is a transition region in which the plate thickness changes in an inclined manner, each of the tools U12, U22, U32, L12, L22, and L32 has, for example, a vertical position of the tip end surface in the width direction. It is changing (inclined) (see FIG. 2C).

  FIG. 2B shows a case where each region of the material P2 is created with a plurality of groups of tools divided in the width direction. FIG. 2C shows a continuous tool in the width direction capable of creating the material P2 of the same form. The tool U1 shown in FIG. 2C is obtained by integrating the tools U11, U12, and U13 shown in FIG. 2B. Similarly, the tool U2 is obtained by integrating the tools U21, U22, and U23, and the tool U3 is obtained by integrating the tools U31, U32, and U33.

  The tool L1 is an integrated tool of the tools L11, L12, and L13 shown in FIG. 2B, the tool L2 is an integrated tool of the tools L21, L22, and L23, and the tool L3 is an integrated tool of the tools L31, L32, and L33.

  The tools U0 to U4 are set in the housing Uc to form the upper mold U, and the tools L0 to L4 are set to the housing Lc to form the lower mold L. The upper mold U and the lower mold L are vertically arranged to form a set K.

  The tip surfaces of tools U11, U12, U13, tools U21, U22, U23 or tools U31, U32, U33 shown in FIG. 2B can take various forms in the width direction. For example, as shown in FIG. 2D, a cross section (cross section E or F in FIG. 2B) of each tool in the width direction may be a flat surface or an inclined surface.

《Thickness distribution in the longitudinal and width directions》
If the above-described tensile bending step and bending ironing step are performed continuously (as one step), a material having a thickness distribution in both the longitudinal direction and the width direction of the plate material can be efficiently created. An example is shown in FIGS. 3A and 3B (these are simply referred to as “FIG. 3”). 1 and FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  When the plate material P0 is pulled out between the tools as shown in FIG. 3, as shown in FIG. 3A, regions r11 and 15 where the plate thickness is reduced in the longitudinal direction and regions r21 and 25 where the plate thickness is reduced in the width direction. The raw material P3 having regions r12, 14 in the longitudinal direction in which the plate thickness transitions, regions r22, 24 in the width direction, and a region r13 (r23) in which the plate thickness remains almost initial can be obtained in one step. Note that, of course, the vertical position of each tool (or mold) is not constant during the process, but moves up and down according to each area to be processed (that is, in conjunction with the drawing position (length) of the plate material). As a result, each region where the tensile bending process or the bending and ironing process is performed or the reverse process is not performed is formed, and a press-forming material having a desired form having a different plate thickness in each region is obtained.

  It was confirmed as follows that a material having a reduced thickness was obtained by tensile bending or bending and ironing. The present invention will be described in more detail with reference to specific examples.

《Lateral thickness reduction》
(1) Tool An upper mold U and a lower mold L shown in FIG. 4 were prepared to reduce the thickness of the sheet material in the longitudinal direction by tensile bending. The upper mold U has convex portions U1, U2, U3 corresponding to a tool. The lower surface positions of these convex portions were the same. The radius of curvature (simply referred to as “shoulder R”) of the shoulder (cross section) of each projection is also shown in FIG. The rear (upstream) side is defined as the left side and the forward (downstream) side is defined as the right side in the drawing direction (the same applies to the lower mold L).

  The lower mold L has tools L1 to L5. The upper surface position of each tool and the shoulder R of each tool are also shown in FIG. Each upper surface position is the amount of displacement (the upper direction is the positive direction) from the lower surface position (upper surface / reference surface) of the test piece T (plate material).

(2) Creation A test piece T (700 mm × 100 mm × t2.3 mm) made of a mild steel plate (JIS SPCC) was sandwiched between the upper mold U and the lower mold L described above. The test piece T was pulled out while a predetermined pressure was applied between both molds. At this time, each bending portion of the test piece T is in a state where a tensile force generated by bending / unbending on the entrance side (rear side, upstream side) is applied.

  When the test piece T was created at an applied pressure of 65 kN, the thickness of the test piece T was reduced from 2.27 mm (measured value of the drawn portion) to 1.52 mm.

  Similar processing was performed in multiple steps. FIG. 4 also shows the pressing force, the number of times (the number of repetitions of processing), and the plate thickness after processing. It has been found that the plate thickness can be significantly reduced even with a small pressing force by using multiple tensile bending steps. For example, when processing was performed six times, the plate thickness was reduced to で with a pressing force of about ５ in rolling.

《Thickness reduction in width direction》
(1) Tool An upper model U and a lower model L shown in FIG. 5A were set as an analysis model for reducing the thickness of the sheet material in the width direction by bending and ironing. The upper mold U is composed of tools U11 to U13, U2, U31 to 33, and the lower mold L is composed of tools L1, L2, L3. Here, the case where the thickness of the end portion of the plate material is reduced is mainly analyzed. For this reason, the focus was mainly on the tools U11, U2, and U31 and the tools L1, L2, and L3 that form a pair with them. The test piece T was the above-mentioned mild steel plate (initial plate thickness: t0 = 2.3 mm).

The vertical position of each tool is indicated by a Z coordinate value with the lower surface position of the test piece T (plate material) (upper surface / reference surface of the holding portion L0) being 0. Z _U33 = Z _U13 = 2.3 means that it is the same as the plate thickness (2.3 mm) of the test piece T, and there is no decrease in the plate thickness at the center (the initial plate thickness remains). . DZ _U32 = 0.5 * DZ _U31 , DZ _U12 = 0.5 * DZ _U11 indicate that the vertical displacements (DZ) of the tools U32 and U12 in the transition area are respectively the vertical displacements of the tools U31 and U11 at the ends ( DZ) (0.5 times).

D _U2 = 2.8 means that the lower end face of the tool U2 is 2.8 mm above the reference plane (Z _U2 = 2.8). D _L2 = 0.5 means that the upper end face of the tool L2 is 0.5 mm below the reference plane (Z _L2 = −0.5). And the gap of the tool U31 and tool _{L3 (DC3 = | Z U31 -Z} L3 |) clearance tool U11 and tool _{L1 (DC1 = | | Z U11} -Z L1) and by each ironing of the specimen T (C1 = T0-DC1, C3 = t0-DC3). Here, C3 = 0.87.

Note that D3 = 1.05 means that the upper end face of the tool L3 is 1.05 mm below the reference plane (Z _L3 = −1.05). Therefore, the lower end face of the tool U31 is located 0.38 mm below the reference plane ( _ZU31 = 0.38).

(2) Analysis The simulation was performed by variously changing the ironing amount (C1) and the position of the upper end surface of the tool L1 (distance from the reference plane: D1 = | Z _L1 |). One example is shown in FIG. 5B.

When C1 = 0.6 and D1 = 2.4 (Z _L1 = −2.4, Z _U11 = −0.7) (upper side in FIG. 5B), the test piece T is placed between the tool U11 and the tool L1. , While being bent, receives the first-stage ironing (ironing amount C1). Thereafter, the test piece T bends and passes between the tool U2 and the tool L2, and receives the second-stage ironing (ironing amount C3) while being bent between the tool U31 and the tool L3. At this time, the strain (calculated value) applied to the plate was small, and it was confirmed that the plate did not clog between the tools and smoothly plastically deformed (reduced thickness).

  FIG. 5C shows a change in the thickness of the test piece T in the width direction after the processing. It was confirmed that the plate thickness at the end was substantially equal to the plate thickness (t0-C3 = 2.3-0.87 = 1.43 mm) after subtracting the second-stage ironing amount (C3).

On the other hand, when C1 = 0.6 and D1 = 0 ( _ZL1 = 0, _ZU11 = 1.7) (lower side in FIG. 5B), the test piece T is bent between the tool U11 and the tool L1. Receive the first ironing without any. Thereafter, the test piece T passes between the tool U2 and the tool L2, is guided between the tool U31 and the tool L3, and receives the second-stage ironing. At this time, the strain (calculated value) applied to the plate becomes extremely large, the plate becomes clogged between the tools, and the plate buckles. Therefore, in this case, it is impossible to smoothly reduce the thickness.

  From the above, it was confirmed that according to the creation method of the present invention, it is possible to smoothly reduce the plate thickness with a relatively small processing force by the tensile bending or the bending and ironing.

P plate material U upper mold (tool)
L lower mold (tool)
r region

Claims (7)

A tool disposed on at least one side of the band-shaped plate over the entire width of the plate is used to push the plate to be pulled out in one of the thickness directions and to bend the plate to bend the plate, thereby reducing the thickness of the plate. Comprising a tensile bending process to form a reduced area,
A method for producing a material for press molding in which regions having different thicknesses in the longitudinal direction are distributed. By using a tool disposed on a part of the width of the band-shaped plate in opposition to both sides of the plate, the plate to be pulled out is pressed into one of the plate thickness directions while being pressed, and the plate is bent and ironed. Including a bending and ironing step for forming a region where the thickness of the plate material is reduced,
A method for producing a press-forming material in which regions having different thicknesses in the width direction are distributed.   Creation of a press-forming material in which regions having different thicknesses in the longitudinal direction and the width direction are distributed by performing at least one time each of the tension bending step described in claim 1 and the bending ironing step described in claim 2. Method. At least one surface side of the band-shaped plate is provided, a tool having a uniform cross-sectional shape at least on a tip side slidingly contacting the plate over the entire width of the plate,
An apparatus for producing a material for press molding used in the method for producing according to claim 1. At least a part of the width of the band-shaped plate is provided with a tool disposed opposite to both sides of the plate,
An apparatus for producing a material for press molding used in the method for producing according to claim 2.   An apparatus for creating a blank for press forming, comprising at least one set of the tool according to claim 4 and the tool according to claim 5. A pull-out means for pulling out a strip-shaped plate;
Pushing means for pushing the tool in the thickness direction,
The creation device according to any one of claims 4 to 6, further comprising: