JP2009050863A - Die for forming material having thickness difference - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the quality of press formed goods composed of materials having thickness difference by simplifying the constitution and also surely holding the material having thickness difference which has portions where are different in thickness. <P>SOLUTION: This press forming apparatus 50 is provided with a die part 56 on which the material 54 having thickness difference to be press-formed and a holder part 60 which is provided adjacently to the die part 56 and with which the material 54 having thickness difference can be held to the die part 56 and a plurality of variable holders 72 faced to the material 54 having thickness difference is provided on an upper die 62 which comprises the die part 56. These variable holders 72 are respectively brought into contact with the thin plate portion 54a, the thick plate portion 54b and the joining portion 54c where the thin plate portion 54a and the thick plate portion 54b are joined and they are held between the die part 56 and itself. When the press forming of the material 54 having thickness difference is performed with the die part 56, the shift along the longitudinal direction of the material 54 having thickness difference is restrained with the holder part 60. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a die for forming a differential thickness material for press-molding differential thickness plates having partially different plate thicknesses.

  2. Description of the Related Art Conventionally, there has been known a press forming apparatus that presses a steel plate into a desired shape by loading a thin plate such as a steel plate into a mold in press working and applying pressure to the thin plate through a press machine or the like. ing.

  As shown in FIG. 13, the press molding apparatus 1 includes an upper mold 6 via a pad pressure adjusting means 5 having a plurality of elastic bodies 4 capable of adjusting pressure on a slide side holder 3 constituting a press machine 2. And a lower die 8 on which a steel plate or the like is placed on the bolster side holder 7 in the press machine 2 is provided. The upper mold 6 is provided with a pressure transmission body 10 having a rod 9, and the pressure transmission body 10 is disposed between the elastic body 4 and a pad 11 facing the lower mold 8 (for example, Patent Document 1). reference).

  And the pressure of the some elastic body 4 which comprises the pad pressure adjustment means 5 is each set, and the said elastic body 4 is each with respect to the steel plate used as a workpiece | work by driving the pressure transmission body 10 according to the said pressure. It is held in contact with the desired part.

JP-A-8-90096

  By the way, in the prior art which concerns on patent document 1, since the pad pressure adjustment means 5 is provided between the press machine 2 including the slide side holder 3 and the upper mold | type 6, in order to provide this pad pressure adjustment means 5 There is a problem in that the structure of the upper mold 6 becomes complicated and the mold cost increases accordingly.

  In addition, there is a desire to perform press molding of differential thickness materials having different plate thicknesses using such a press molding apparatus 1, and in that case, in order to securely hold the differential thickness material, the differential thickness It is necessary to adjust the pressure in accordance with the part holding the material, and there are problems that the adjustment work is complicated and the work efficiency is lowered.

  The present invention has been made in consideration of the above-mentioned problems, and while simplifying the configuration, the entire differential thickness material having parts with different plate thicknesses is reliably and easily maintained, and the quality of the press-formed product is improved. An object of the present invention is to provide a die for forming a differential thickness material that can be achieved.

In order to achieve the above object, the present invention provides a method for forming a differential thickness material used in a press molding apparatus for forming a workpiece by applying pressure to a differential thickness plate having a partially changed thickness. In the mold,
A first mold that is displaced along the axial direction under the drive action of the drive unit in the press molding apparatus;
A second mold disposed at a position facing the first mold;
A holding mechanism that faces the differential thickness material and is capable of holding the differential thickness material with respect to either the first mold or the second mold,
With
The holding mechanism is provided along the longitudinal direction of the differential thickness material, and holds a constant plate thickness portion in the differential thickness material; and
It has a 2nd holding part which adjoins the said 1st holding | maintenance part and hold | maintains the board thickness change part from which the said board thickness changes in the said difference thickness material.

  According to the present invention, a holding mechanism for holding a differential thickness material to be press-molded is provided, and the holding mechanism is capable of holding a constant plate thickness portion of the differential thickness material, and the first holding portion. And a second holding part that holds the plate thickness changing part of the differential thickness material. Then, press molding can be performed by the first and second molds in a state where the constant plate thickness portion of the differential thickness material is held by the first holding portion and the constant plate thickness portion is held by the second holding portion. Therefore, the plate thickness changing portion of the differential thickness material can be reliably held by the second holding portion constituting the holding mechanism. Therefore, when performing the press molding of the differential thickness material, it is combined with the first holding portion. The differential thickness material can be reliably and easily held in a wider range.

  As a result, the amount of movement along the longitudinal direction of the differential thickness material during press molding can be suitably suppressed with a simple configuration such as providing a holding mechanism having first and second holding portions. Load concentration on the material can be prevented, and the quality of the press-formed product made of the differential thickness material can be improved.

  In addition, the first and second holding portions include the holding body that can freely contact the differential thickness material, and an urging unit that urges the holding body toward the differential thickness material side. The body is suitably pressed against the differential thickness material under the urging action of the urging means, and the differential thickness material is securely held via the holding body.

  Further, the holding body of the second holding portion is formed with an end surface that contacts the differential thickness material corresponding to the thickness change portion of the differential thickness material, so that the end surface of the holding body is the plate thickness of the differential thickness material. It is possible to hold the change part in a suitable surface contact. Therefore, the plate thickness changing portion of the differential thickness material can be reliably and firmly held by the second holding portion having the holding body.

  Furthermore, the holding body of the second holding portion is configured such that the width dimension along the longitudinal direction of the differential thickness material is set to be smaller than the width dimension of the holding body in the first holding portion. A plurality of second holding portions can be provided according to the plate thickness change state of the thickness change portion. As a result, the plate thickness changing portion having a large shape change can be more reliably held by the second holding portion. In addition, by setting the holding body of the first holding part to be larger than the width dimension of the holding body in the second holding part, the number of first and second holding parts constituting the holding mechanism can be reduced. Accordingly, it is possible to reduce the number of parts and improve the assembly workability.

  According to the present invention, the following effects can be obtained.

  That is, the holding mechanism for holding the differential thickness material includes a first holding portion capable of holding a constant plate thickness portion of the differential thickness material, and a plate thickness changing portion of the differential thickness material adjacent to the first holding portion. Since the plate thickness changing portion can be reliably held by the second holding portion of the holding mechanism at the time of press molding by configuring it with the possible second holding portion, the difference thickness is combined with the first holding portion. The material can be reliably and easily held in a wider range. As a result, with a simple configuration such as providing a holding mechanism composed of the first and second holding portions, the amount of movement along the longitudinal direction of the differential thickness material during press molding is suitably suppressed and applied to the differential thickness material. Therefore, it is possible to improve the quality of the press-formed product made of the differential thickness material.

  A preferred embodiment of a die for forming a differential thickness material according to the present invention will be described and described in detail below with reference to the accompanying drawings.

  In FIG. 1, reference numeral 50 indicates a press molding apparatus using the differential thickness material molding die according to the first embodiment of the present invention.

  As shown in FIGS. 1 to 3, the press molding apparatus 50 includes a body 52, a mold part 56 that is held on a part of the body 52 and placed on a differential thickness material 54 that is press-molded. A drive unit 58 for driving the mold part 56 along the axial direction (arrows A1 and A2 directions), and the differential thickness material 54 with respect to the mold part 56 when the differential thickness material 54 is press-molded. And a holder portion (holding mechanism) 60 that can be held.

  First, the differential thickness material 54 that is press-formed by the press-forming apparatus 50 described above will be briefly described. The differential thickness material 54 is joined to the thin plate portion 54a having a thin plate thickness (constant thickness portion) 54a provided on one end side along the longitudinal direction (arrow B direction) and the differential thickness material 54a. A thick plate portion (constant plate thickness portion) 54b provided on the other end side of 54 and formed thicker than the thin plate portion 54a, and the thin plate portion 54a and the thick plate portion 54b are laser welded or the like. And a joint part (plate thickness changing part) 54c joined together.

  The thin plate portion 54a and the thick plate portion 54b are each formed with a constant plate thickness, and the joining portion 54c is joined so that one surface of the thin plate portion 54a and one surface of the thick plate portion 54b are flush with each other. The other surface of the thick plate portion 54b and the other surface of the thin plate portion 54a that are stepped are joined in an inclined manner so as to be inclined from the thick plate portion 54b side toward the thin plate portion 54a side.

  Further, since the joining portion 54c is formed by laser welding or the like, the vicinity of the boundary portion with the thick plate portion 54b may have a convex shape slightly raised with respect to the surface of the thick plate portion 54b (FIG. 4A). And FIG. 4B).

  The press molding apparatus 50 for press-molding such a differential thickness material 54 has a body 52 comprising a base 64 for holding an upper mold (second mold) 62 constituting a mold part 56, and the upper mold 62 and a lower mold (first mold) 66 which is provided below the upper mold 62 and is displaced toward the upper mold 62 side (in the direction of the arrow A1) under the driving action of the drive unit 58. A mold part 56 is formed.

  In the upper mold 62, the differential thickness material 54 is press-formed, and a cavity 68 corresponding to a predetermined shape (for example, a body panel) is formed to be recessed.

  On the other hand, the lower die 66 is disposed so as to face the cavity 68 formed in the upper die 62 and has a cross-sectional shape corresponding to the cavity 68. Then, the lower die 66 is displaced toward the upper die 62 side (in the direction of arrow A1) under the driving action of the drive unit 58, and a part thereof is inserted into the cavity 68 of the upper die 62.

  Further, on the lower end surface of the upper mold 62 facing the lower mold 66, concave portions 70 that are recessed in the same direction as the cavity 68 are formed on both sides of the upper mold 62 with the cavity 68 interposed therebetween (see FIG. 2). . The recess 70 extends toward both side surfaces of the upper mold 62 with a predetermined width, and is provided at a substantially central portion along the longitudinal direction (arrow B direction) of the upper mold 62, and its bottom wall surface is substantially flat. It is formed in a shape. A plurality of variable holders 72 that are displaceable in the axial direction toward the lower mold 66 and the differential thickness member 54 are provided inside the recess 70.

  Further, the lower end surface of the upper mold 62 faces the thick plate portion 54b of the differential thickness material 54, and faces the first contact portion 74 that contacts the thick plate portion 54b, and the thin plate portion 54a of the differential thickness material 54, A second abutting portion 76 that abuts against the thin plate portion 54 a, and the first abutting portion 74 and the second abutting portion 76 are disposed so as to sandwich the recess 70.

  The first contact part 74 is provided on one end side along the longitudinal direction of the upper mold 62, the second contact part 76 is provided on the other end part side of the upper mold 62, and the recess 70 is provided therebetween. It has been. The first and second contact portions 74 and 76 are each formed in a substantially planar shape, and the first contact portion 74 is on the lower mold 66 side with respect to the second contact portion 76 (in the direction of arrow A2). And projecting by a predetermined height toward the surface. Thereby, when the differential thickness material 54 contacts the first and second contact portions 74 and 76, the first contact portion 74 contacts the thick plate portion 54b, and the second contact portion 76 corresponds to the thin plate portion 54a. And the concave portion 70 is disposed in the vicinity of the joint portion 54c between the thin plate portion 54a and the thick plate portion 54b. Specifically, the recess 70 is formed so as to face a part of the thin plate portion 54a and the thick plate portion 54b with the joint portion 54c as the center.

  4A and 4B, a plurality of (for example, five) variable holders 72 are arranged in parallel with the recess 70 along the longitudinal direction (arrow B direction) of the upper mold 62. A base portion 78 fixed to the bottom wall surface, a variable block (holding body) 80 that can be held by contacting the surface of the differential thickness material 54, and provided between the base portion 78 and the variable block 80; And a spring (biasing means) 82 that urges the variable block 80 toward the differential thickness member 54 (in the direction of arrow A2). In other words, the variable holder 72 is arranged in parallel with the upper mold 62 so as to follow the longitudinal direction (arrow B direction) of the differential thickness material 54.

  Here, a case where five variable holders 72 are provided for each of the recesses 70 will be described, and the variable holder 72 disposed closest to the first contact portion 74 (in the direction of arrow B1) is the first variable. The case where the second to fifth variable holders 72b to 72e are arranged in order from the first variable holder 72a toward the second contact portion 76 side (arrow B2 direction) will be described.

  In this case, the first and second variable holders (first holding portions) 72a and 72b are arranged to face the thick plate portion 54b, and the fourth and fifth variable holders (first holding portions) 72d and 72e are The third variable holder (second holding portion) 72c disposed at the center faces the joint portion 54c that is a boundary portion between the thin plate portion 54a and the thick plate portion 54b. Are arranged as follows.

  The first and second variable holders 72a and 72b are arranged adjacent to each other. Similarly, the third to fifth variable holders 72c to 72e are arranged adjacent to each other, and the second variable holder 72b and the third variable holder 72b are connected to each other. The variable holder 72c is disposed at a predetermined interval, and a space 84 is provided therebetween.

  The space 84 is provided so as to avoid a boundary portion between the joining portion 54 c and the thick plate portion 54 b in the differential thickness material 54. It should be noted that the first to fifth variable holders 72a to 72e are adjacent to each other without providing the space 84 without assuming a case where the joint 54c and the thick plate 54b are formed in a convex shape. You may arrange in.

  The base portion 78, the variable block 80, and the spring 82 constituting the first to fifth variable holders 72a to 72e described above are arranged on a straight line along the displacement direction (arrow A1 direction) of the lower mold 66, and are on a straight line. The disposed base portion 78 and the variable block 80 are formed with substantially the same width dimension.

  The width of the variable block 80 is such that the first and second variable holders 72a and 72b, the fourth and fifth variable holders 72d are arranged so as to be able to contact the thin plate portion 54a and the thick plate portion 54b of the differential thickness material 54. 72e is set to be large, and the third variable holder 72c is set small to be able to come into contact with the joint portion 54c between the thick plate portion 54b and the thin plate portion 54a.

  Specifically, the first and fifth variable holders 72a and 72e farthest from the joint 54c are set to have the largest width dimension, and the second and fourth variable holders adjacent to the first and fifth variable holders 72a and 72e are set. The width dimensions of the holders 72b and 72d are set slightly smaller than the width dimensions of the first and fifth variable holders 72a and 72e.

  In other words, in the differential thickness material 54 composed of the thin plate portion 54a and the thick plate portion 54b, the width dimension of the variable block 80 that holds the thin plate portion 54a and the thick plate portion 54b with a small change in plate thickness is set large. The width dimension of the variable block 80 that holds the joint 54c and the vicinity of the portion where the change in the plate thickness is large is set small. As a result, the end face of the variable block 80 can be more reliably brought into surface contact with the surface of the differential thickness material 54, so that the differential thickness material 54 can be held with respect to the holder portion 60. .

  The variable blocks 80 of the first and second variable holders 72a and 72b and the fourth and fifth variable holders 72d and 72e have a flat bottom surface facing the differential thickness material 54 corresponding to the thick plate portion 54b and the thin plate portion 54a. In the lower surface of the variable block 80 that is formed in the shape of the third variable holder 72c, an inclined surface (end surface) 80a that is inclined at a predetermined angle according to the joint 54c is formed. That is, the inclined surface 80a is formed substantially in parallel with the contact portion 54c that comes into contact, and when the variable block 80 of the third variable holder 72c comes into contact with the joint portion 54c, the joint portion 54c is interposed via the inclined surface 80a. Can be brought into surface contact.

  In addition, the lower surface of the variable block 80 is not limited to the case where the inclined surface 80a inclined at a predetermined angle is formed, and the shape according to the surface shape of the joint portion 54c with which the lower surface of the variable block 80 abuts. What is necessary is just to be formed.

  The spring 82 is formed of, for example, a gas spring having a predetermined elastic force when gas is press-fitted therein, and the variable block 80 is moved toward the thickness difference material 54 (in the direction of arrow A2) under the urging action of the elastic force. It is pushed and displaced.

  The driving unit 58 includes a press machine 86 to which a pressurizing force is applied hydraulically upward (in the direction of the arrow A1) under energization, and a plate 88 provided on the upper surface of the press machine 86. A lower die 66 is attached to a substantially central portion of 88 and extends toward the upper die 62 (in the direction of arrow A1). Then, when the press machine 86 is operated, the press machine 86 displaces the lower mold 66 to the upper mold 62 side (arrow A1 direction) in a state where a predetermined pressing force is urged through the plate 88.

  The holder portion 60 is provided so as to face the upper die 62 with respect to the plate 88 constituting the driving portion 58, and is provided so as to be displaceable toward the upper die 62 side (arrow A1 direction). The holder portion 60 is provided between a pair of holding blocks 90 that hold the differential thickness material 54 disposed between the upper die 62 and the lower die 66, and between the plate 88 and the holding block 90. And a cylinder 92 that urges the holding block 90 toward the upper mold 62 side.

  The holding block 90 is composed of a plurality of (for example, two) block bodies having a predetermined width, and is held in contact with one surface of the differential thickness material 54 formed in the same plane on the upper surface facing the upper mold 62. It has a possible contact surface 90a.

  The press molding apparatus 50 using the differential thickness material molding die according to the first embodiment of the present invention is basically configured as described above, and next, its operation and effects. Will be described.

  First, as shown in FIGS. 1 and 2, the differential thickness material 54 serving as a workpiece is disposed between the upper mold 62 and the lower mold 66 so as to face the cavity 68. As shown in FIG. 1, the holder portion 60 disposed on the plate 88 is urged toward the differential thickness material 54 side (in the direction of the arrow A <b> 1) by the cylinder 92, and the holding block 90 is moved to the differential thickness material 54. The thin plate portion 54a, the thick plate portion 54b, and the joining portion 54c are configured so as to be pressed toward the differential thickness material 54 side. As a result, the differential thickness material 54 is held in contact with the lower end surface of the upper mold 62 by the holder portion 60.

  At this time, the thick plate portion 54 b is held in contact with the first contact portion 74 of the upper mold 62, and the thin plate portion 54 a is held in contact with the second contact portion 76. On the other hand, the thin plate portion 54a and a part of the thick plate portion 54b and the joint portion 54c between the thin plate portion 54a and the thick plate portion 54b are respectively held by the first to fifth variable holders 72a to 72e constituting the variable holder 72. ing.

  Next, by actuating the hydraulic pressure on the press machine 86 constituting the drive unit 58, the lower die 66 connected to the press machine 86 via the plate 88 is integrally moved upward (arrow A1) along the axial direction. Direction). Then, the lower die 66 abuts across the thin plate portion 54a, the thick plate portion 54b, and the joining portion 54c of the differential thickness material 54, and the press machine 86 pressurizes upward, whereby the upper end portion of the lower die 66 is contacted. The differential thickness material 54 is pushed into the cavity 68, and the thin plate portion 54 a, the thick plate portion 54 b and the joint portion 54 c are plastically deformed and flow into the cavity 68.

  In this case, when the differential thickness material 54 is pushed into the cavity 68, a tensile force is generated in the differential thickness material 54 in the longitudinal direction (arrow B1, B2 direction). Since the joining portion 54c is held on the lower die 66 side by the inclined surface 80a of the third variable holder 72c constituting the variable holder 72 provided in the upper die 62, the differential thickness material 54 when press molding is performed. The movement along the longitudinal direction (arrow B direction) is suppressed (see FIG. 4B).

  That is, the third variable holder 72c capable of holding the joint 54c of the differential thickness material 54 holds the joint 54c with a pressing force that presses the joint 54c toward the lower mold 66 (in the direction of arrow A2), and the joint 54c. The difference thickness material 54 including the first difference thickness material 54 is brought into contact with the holder portion 60, and in the longitudinal direction (arrow B direction) of the difference thickness material 54 by the inclined surface 80a of the variable block 80 constituting the third variable holder 72c. The movement along is regulated.

  Then, when the press machine 86 is further displaced upward and displaced to a preset displacement end position, the upper end portion of the lower die 66 is pushed into the inside from the lower surface of the differential thickness material 54 that is plastically deformed, and The thin plate portion 54a of the differential thickness material 54 is press-formed into a desired shape by the cavity 68 and the lower mold 66 (see FIG. 3).

  Further, in this case, as described above, when the thin plate portion 54a of the differential thickness material 54 is further pushed into the cavity 68, the differential thickness material 54 is pulled toward the cavity 68 side at both ends thereof. The variable block 80 of the third variable holder 72c is pushed down slightly against the elastic force of the spring 82 by the joint 54c of the differential thickness material 54, and a part of the joint 54c is attached to the third variable holder 72c. Locked to the variable block 80 of the adjacent fourth variable holder 72d. That is, further movement along the longitudinal direction (arrow B direction) of the differential thickness member 54 is suppressed by the third and fourth variable holders 72c and 72d.

  Finally, the displacement direction of the press machine 86 constituting the drive unit 58 is switched, and the lower die 66 is displaced in the direction away from the upper die 62 (arrow A2 direction) via the plate 88, and then the cylinder 92 is attached. The holder 60 holding the differential thickness material 54 under the urging action is displaced in a direction away from the upper mold 62. As a result, a press-molded product obtained by press-forming the thin plate portion 54a, the thick plate portion 54b, and the joining portion 54c, which are the central portion of the differential thickness material 54, is taken out (see FIG. 5).

  Here, the case where press molding is performed using a differential thickness material molding die in which the variable holder 72 is not provided in the holding block 90 of the holder portion 60 will be briefly described with reference to FIGS. 6A and 6B. The holding block 90b constituting the holder portion 60a is provided with a first recess 94a at a position corresponding to the joining portion 54c of the differential thickness material 54, and a second lower end surface of the upper mold 62a facing the first recess 94a. Two recesses 94b are provided. That is, the first and second recesses 94a and 94b are provided so as to avoid the joint portion 54c in the differential thickness material 54, and the width dimension thereof is set larger than the width dimension of the joint portion 54c.

  Then, the thin plate portion 54a and the thick plate portion 54b of the differential thickness material 54 are held by the holder portion 60a through the holding block 90b, and press molding is performed by the mold portion 56a including the upper die 62a (see FIG. 6B).

  At this time, since the joining portion 54c is accommodated in the first and second recesses 94a and 94b of the holding block 90b and the upper die 62a, the joining portion 54c does not come into contact with the holding block 90b and the upper die 62a. 54c becomes a non-holding state (refer FIG. 6B). Therefore, when the differential thickness material 54 is pulled along the longitudinal direction (arrow B direction) at the time of press forming, the joint portion 54c moves together with the thin plate portion 54a or the thick plate portion 54b, and the joint portion 54c becomes the first portion. The second concave portions 94a and 94b are in contact with the side surfaces and locked. Thereby, the movement amount along the longitudinal direction (arrow B direction) of the differential thickness material 54 including the joint portion 54c cannot be controlled, and the joint portion 54c becomes the first and second concave portions 94a and 94b. Since the load is applied intensively in the contacted state, there is a concern that a crack or the like may occur in the differential thickness material 54 accordingly.

  On the other hand, in the present embodiment, as shown in FIGS. 4A and 4B, the holder portion 60 that holds the differential thickness material 54 to be press-molded is provided, and the concave portion 70 that constitutes the upper die 62 is provided. A plurality of variable holders 72 are provided so as to face the differential thickness material 54. When the differential thickness material 54 having the thin plate portion 54a and the thick plate portion 54b having different plate thicknesses is press-formed, the thin plate portion 54a and the thick plate portion 54b are held by the holding block 90, and the thin plate portion 54a and A part of the thick plate portion 54b and a joint portion 54c between the thin plate portion 54a and the thick plate portion 54b are respectively held by a plurality of first to fifth variable holders 72a to 72e.

  Thereby, since the joining part 54c where the plate thickness changes and the vicinity thereof can be reliably held by the plurality of variable holders 72a to 72e constituting the holder part 60, the differential thickness material 54 is press-molded. In this case, the differential thickness material 54 can be reliably held in a wider range.

  As a result, the amount of movement along the longitudinal direction (arrow B direction) of the differential thickness material 54 during press molding can be suppressed, and concentration of load on the joint 54c of the differential thickness material 54 can be prevented. Therefore, it is possible to prevent the occurrence of cracks or the like in the joint portion 54c. Therefore, the quality of the press-formed product made of the above-described differential thickness material 54 can be improved, and the yield can be improved.

  In addition, the plurality of variable holders 72a to 72e are set to have a width dimension according to the portion of the differential thickness member 54 with which the variable block 80 abuts, and the portion of the differential thickness member 54 where the plate thickness change is large (joint portion 54c). And in the vicinity of the joint portion 54c), the width dimension is reduced and held locally, and the width dimension is increased in a wide range at a portion where the plate thickness change is small (thin plate portion 54a and thick plate portion 54b). Are held together. As a result, the quantity of the variable holders 72 provided in the holding block 90 constituting the holder portion 60 is minimized, and the cost is reduced, and the number of assembling steps for the holding block 90 and the elasticity of the spring 82 are adjusted. Man-hours for work can be reduced.

  Further, the variable block 80 of the third variable holder 72c that holds the bonding portion 54c is provided with an inclined surface 80a facing the bonding portion 54c, so that the bonding portion is inclined from the thick plate portion 54b toward the thin plate portion 54a. The inclined surface 80a can be reliably brought into surface contact with the surface of 54c and held.

  Furthermore, since the variable holder 72 constituting the upper die 62 is disposed inside the recess 70, conventional press molding in which pad pressure adjusting means is provided between the press machine 86 and the upper die 62. Compared with the apparatus, the height dimension of the press molding apparatus 50 including the die for forming the differential thickness material can be suppressed.

  Next, referring to FIG. 7A and FIG. 7B for the case where the differential thickness material 100 rolled by the rolling device having a rolling roller or the like is press molded by the press molding device 50 using the above-described differential thickness material molding die. While explaining. Note that the same components as those in the press forming apparatus 50 according to the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  The differential thickness material 100 includes, for example, a thin portion (plate thickness constant portion) 100a in which a plate material having a constant thickness is rolled by a rolling roller of a rolling device (not shown) to form a thin plate thickness, and both end portions of the thin portion 100a. The outer peripheral diameter of the rolling roll is formed at the boundary portion between the thick portion (plate thickness constant portion) 100b and the thin portion 100a and the thick portion 100b. And a joint portion (plate thickness changing portion) 100c formed in an arc shape in cross section.

  The joint portion 100c connects the surface of the thin portion 100a and the surface of the thick portion 100b in an arc shape in cross section, and the thickness of the joint portion 100c is from the thin portion 100a side (arrow B2 direction) to the thick portion 100b. It gradually increases toward the side (arrow B1 direction).

  In the press molding apparatus that performs the press molding of the differential thickness material 100, the upper mold 62 constituting the differential thickness material molding die includes a first variable holder among the plurality of variable holders 104a to 104e provided in the recess 70. (First holding portion) 104 a is disposed so as to be able to contact the thick portion 100 b of the differential thickness material 100, and the fourth and fifth variable holders (first holding portions) 104 d and 104 e are thin walls of the differential thickness material 100. The second and third variable holders (second holding portions) 104b and 104c are disposed so as to be in contact with the joint portion 100c formed in an arc shape.

  In this case, the width dimension of the variable block (holding body) 106 constituting the variable holder 104 is the first and fifth variable positions arranged so as to be able to contact the thin portion 100a and the thick portion 100b of the differential thickness material 100. The holders 104a and 104e are set larger than the second to fourth variable holders 104b to 104d, and the first, fourth and fifth variable holders 104a, 104d and 104e are lower surfaces facing the differential thickness material 100. Is formed in a flat shape corresponding to the thick portion 100b and the thin portion 100a, and the lower surface of the variable block 106 constituting the second and third variable holders 104b and 104c is predetermined according to the arc-shaped joint portion 100c. Inclined surfaces (end surfaces) 106a and 106b that are inclined at an angle are formed.

  The second to fourth variable holders 104b to 104d are arranged adjacent to each other, the first variable holder 104a and the second variable holder 104b are arranged at a predetermined interval, and a space 110 is provided therebetween. The space 110 is provided at a position facing the boundary portion between the joint portion 100c and the thick portion 100b in the differential thickness material 100.

  When press molding is performed by the press molding apparatus including the holder unit 102 described above, the differential thickness material 100 disposed between the upper mold 62 and the lower mold 66 is held by the holding block 108 of the holder unit 102. In addition, the joint portion 100c and the vicinity thereof in the differential thickness material 100 are pressed by the first to fifth variable holders 104a to 104e provided in the holding block 108, so that the differential thickness material 100 becomes the upper die. 62. In this case, the variable block 106 of the second and third variable holders 104b and 104c abuts on the joint portion 100c of the differential thickness member 100, and the inclined surfaces 106a and 106b of the variable block 106 abut against the arcuate surface. Touch.

  In addition, press molding is performed by the first to fifth variable holders 104a to 104e to press the differential thickness material 100 toward the holder portion 102 (in the direction of arrow A2) with a predetermined pressure. Thereby, the thin portion 100a and the joint portion 100c are pressed toward the holder portion 102, the surface of the thin portion 100a facing the holder portion 102 abuts the holding block 108 of the holder portion 102, and the The joining portion 54c comes into contact with the holding block 108 while being plastically deformed along the surface of the holding block 108 formed in a flat shape.

  Then, the differential thickness material 100 previously held by the holder portion 102 is pressed against the lower die 66 under the driving action of the drive portion 58, and the thin portion of the differential thickness material 100 is pressed by the lower die 66. 100a is pushed into the cavity 68, and the thin portion 100a is plastically deformed.

  Here, when press molding is performed using a differential thickness material molding die in which the variable holder 104 is not provided in the upper die 62, as shown in FIGS. 8A and 8B, the first die of the upper die 62b is used. The contact part 74a is extended to a position facing the joint part 100c of the differential thickness member 100, and the second contact part 76a of the upper mold 62b is formed to face the thin part 100a. And the thin part 100a and the thick part 100b of the difference thickness material 100 are hold | maintained by the upper mold | type 62b and the holder part 102, and press molding is performed by the metal mold | die part 56b containing the upper mold | type 62b.

  At this time, since the joining portion 100c is opposed to the second contact portion 74a capable of holding the thick portion 100b having a large plate thickness, the joining thickness is gradually reduced with respect to the thick portion 100b. The portion 100c is not held, and the joint portion 100c is not held with respect to the holding block 108a (see FIG. 8B).

  Therefore, when the differential thickness material 100 is pulled along the longitudinal direction (arrow B direction) during press molding, the joint portion 100c moves together with the thin portion 100a or the thick portion 100b, and the joint portion 100c becomes the first portion. The boundary surface between the contact portion 74a and the second contact portion 76a comes into contact with and is locked. Thereby, the amount of movement along the longitudinal direction of the differential thickness member 100 including the joint portion 100c cannot be controlled, and a load is applied intensively in a state where the joint portion 100c is in contact with the boundary surface. Therefore, there is a concern that a crack or the like may occur in the differential thickness material 100.

  In addition, when the thickness difference material 100 is pressed by the upper mold 62b and the holder portion 102, the joint portion 100c does not abut against the holding block 108a, so that the deformation of the joint portion 100c is controlled. It becomes difficult to do so, and the quality of the press-formed product made of the differential thickness material 100 becomes unstable (see FIG. 8B).

  On the other hand, in the present embodiment, when press molding is performed by the press molding apparatus 50, the joint portion 100c of the differential thickness material 100 is inclined by the second and third variable holders 104b and 104c constituting the holder portion 102. Since the surfaces 106a and 106b are respectively held on the holder portion 102 side, the movement of the differential thickness material 100 along the longitudinal direction (arrow B direction) is suppressed.

  As a result, the amount of movement along the longitudinal direction (arrow B direction) of the differential thickness material 100 during press molding can be suppressed including the joint portion 100c, and the load concentration on the joint portion 100c of the differential thickness material 100 can be suppressed. Therefore, the occurrence of cracks or the like in the vicinity of the joint portion 100c can be prevented.

  In addition, when the differential thickness material 100 is pressed, the joint portion 100c is reliably pressed toward the holder portion 102 by the second and third variable holders 104b and 104c. It can be deformed to the part 102 side, and the amount of deformation can be suitably controlled. As a result, it is possible to stabilize the quality of the press-formed product made of the differential thickness material 100.

  Next, FIG. 9 to FIG. 12 show a press molding apparatus 150 using the differential thickness material molding die according to the second embodiment. The same components as those of the press molding apparatus 50 using the differential thickness molding die according to the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted. .

  In the press molding apparatus 150 according to the second embodiment, the differential thickness material 152 includes a thin plate portion 152a disposed at a substantially central portion, and a thick plate portion 152b joined to both end portions of the thin plate portion 152a. The difference thickness material 152 molding die according to the first embodiment in that a plurality of variable holders 72 are provided on the holding block 156 that constitutes the holder portion 154 via the recesses 70. Is different from the press molding apparatus 50 in which is used.

  The holding block 156 constituting the press molding apparatus 150 is composed of a plurality of (for example, two) block bodies having a predetermined width, and the upper surface facing the upper mold 158 contacts the thick plate portion 152b of the differential thickness material 152. Provided between the first contact portion 160 that contacts, the second contact portion 162 that contacts the thin plate portion 152a of the differential thickness material 152, and the first and second contact portions 160 and 162, a plurality of variable A recess 70 in which the holder 72 is disposed is formed.

  The first and second contact portions 160 and 162 are each formed in a substantially planar shape, and the second contact portion 162 is on the upper mold 158 side (arrow A1 direction) with respect to the first contact portion 160. It protrudes by a predetermined height toward it.

  The recess 70 opens toward the upper mold 158 side and is formed to be recessed by a predetermined depth with respect to the upper surface of the holding block 156. Specifically, the recess 70 is recessed with respect to the end surfaces of the first and second contact portions 160 and 162, and the depth with respect to the second contact portion 162 is deeper than the depth with respect to the first contact portion 160. Become.

  Moreover, the recessed part 70 is extended by the predetermined width toward the 1st and 2nd contact part 160,162 side (arrow C direction), and the bottom wall surface is formed in substantially planar shape. A plurality of variable holders 72 that can be displaced along the axial direction toward the upper mold 158 and the differential thickness member 152 are provided inside the recess 70. The variable holder 72 is arranged in parallel to the holding block 156 so as to be along the longitudinal direction (arrow C direction) of the differential thickness material 152. Note that the configuration of the variable holder 72 is the same as the configuration in the first embodiment described above, and a detailed description thereof will be omitted.

  That is, when the holding block 156 contacts the differential thickness material 152, the first contact portion 160 contacts the thick plate portion 152b, the second contact portion 162 contacts the thin plate portion 152a, and the thin plate portion 152a. And the thick plate portion 152b are arranged so that the concave portion 70 faces in the vicinity of the joint portion 152c. Specifically, the recess 70 is formed so as to face a part of the thin plate portion 152a and the thick plate portion 152b with the joint portion 152c as the center.

  In the press molding apparatus 150 having such a configuration, first, as shown in FIG. 12, the differential thickness material 152 serving as a workpiece is disposed between the upper mold 158 and the lower mold 66 so as to face the cavity 68. 9, the holder portion 154 disposed on the plate 88 is urged toward the differential thickness member 152 side (in the direction of the arrow A1) by the cylinder 92, and the holding block 156 and the variable holder 72 are The thin plate portion 152a, the thick plate portion 152b, and the joining portion 152c constituting the differential thickness material 152 are brought into contact with each other and pressed toward the differential thickness material 152 side. As a result, the differential thickness material 152 is held in contact with the end surface of the upper mold 158 by the holder portion 154.

  Next, by supplying hydraulic pressure to the press machine 86 constituting the drive unit 58, the lower die 66 connected to the press machine 86 via the plate 88 is integrally moved upward (arrow A1) along the axial direction. Direction). Then, the lower die 66 abuts against the thin plate portion 152a of the differential thickness material 152, and the press machine 86 is pressurized upward, so that the upper end portion of the lower die 66 causes the thin plate portion 152a of the differential thickness material 152 to move. The thin plate portion 152a is plastically deformed and flows into the cavity 68 by being pushed into the cavity 68 side.

  In this case, when the thin plate portion 152 a of the differential thickness material 152 is pushed into the cavity 68, a tensile force is generated in the differential thickness material 152 toward the cavity 68, which is the central portion thereof. Since the joining portion 152c in 152 is held on the upper mold 158 side by the inclined surface 88a of the third variable holder 72c constituting the holder portion 154, the longitudinal direction (arrows) of the differential thickness material 152 when the press molding is performed Movement along the (C direction) is suppressed (see FIG. 11B).

  That is, the third variable holder 72c capable of holding the joint portion 152c of the differential thickness material 152 holds the joint portion 152c with a pressing force that presses the joint portion 152c toward the upper mold 158 side (arrow A1 direction). The difference thickness material 152 including the first difference thickness material 152 is brought into contact with the upper mold 158, and in the longitudinal direction (arrow C direction) of the difference thickness material 152 by the inclined surface 80a of the variable block 80 constituting the third variable holder 72c. The amount of movement along is suppressed.

  Then, the press machine 86 is further displaced upward to a preset displacement end position, whereby the upper end portion of the lower die 66 is pushed into the inside from the lower surface of the differential thickness material 152 that is plastically deformed, and The thin plate portion 152a of the differential thickness material 152 is press-molded into a desired shape by the cavity 68 and the lower mold 66 (see FIG. 10).

  Further, in this case, as described above, when the thin plate portion 152a of the differential thickness material 152 is further pushed into the cavity 68, both end portions of the differential thickness material 152 are pulled toward the cavity 68, respectively. The variable block 80 of the third variable holder 72c is slightly pushed up against the elastic force of the spring 82 by the joint portion 152c of the differential thickness material 152, and a part of the joint portion 152c is attached to the third variable holder 72c. Locked to the variable block 80 of the adjacent fourth variable holder 72d. That is, further movement along the longitudinal direction (arrow C direction) of the differential thickness material 152 is suppressed by the third and fourth variable holders 72c and 72d.

  Finally, the displacement direction of the press machine 86 constituting the drive unit 58 is switched, and the lower die 66 is displaced in the direction away from the upper die 158 (arrow A2 direction) via the plate 88, and then the cylinder 92 is attached. The holder portion 154 holding the differential thickness material 152 under the urging action is displaced in a direction away from the upper mold 158. As a result, a press-formed product obtained by press-forming the thin plate portion 152a that is the central portion of the differential thickness material 152 is taken out.

  The differential-thickness material molding die according to the present invention is not limited to the above-described embodiment, and can of course have various configurations without departing from the gist of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall external perspective view of a press molding apparatus using a differential thickness material molding die according to a first embodiment of the present invention. It is a whole block diagram of the press molding apparatus shown in FIG. FIG. 3 is an overall configuration diagram illustrating a state where a drive unit is displaced upward in the press molding apparatus of FIG. 2 and a differential thickness material is press molded. 4 shows the vicinity of the holder part in the press molding apparatus of FIG. 1, and FIG. 4A is an enlarged sectional view showing a state before the differential thickness material along the line IVA-IVA of FIG. 2 is held by the holder part. 4B is an enlarged cross-sectional view showing a state in which the differential thickness material along the line IVB-IVB in FIG. 3 is held by the holder portion. It is a whole external perspective view which shows the state by which the thickness difference material was press-molded with the press molding apparatus of FIG. FIG. 6A is an enlarged cross-sectional view showing a comparative example in which a variable holder is not provided in the holder portion constituting the press molding apparatus, FIG. 6A shows a state before the differential thickness material is held by the holder portion, and FIG. The expanded sectional view which shows the state by which the said difference thickness material was hold | maintained by the holder part is shown. FIG. 7 shows the vicinity of the holder portion when the press forming is performed using the difference thickness material that is rolled by a rolling device and partially has a different thickness, and FIG. 7A shows the difference thickness material held by the holder portion. FIG. 7B is an enlarged cross-sectional view showing a state in which the differential thickness material is held by the holder portion. FIG. 8A is an enlarged cross-sectional view showing a comparative example in which a variable holder is not provided in the holder portion constituting the press molding apparatus, FIG. 8A shows a state before the differential thickness material is held by the holder portion, and FIG. The expanded sectional view which shows the state by which the said difference thickness material was hold | maintained by the holder part is shown. It is a whole block diagram of the press molding apparatus in which the metal mold | die for differential thickness material shaping | molding which concerns on 2nd Embodiment of this invention was used. FIG. 2 is an overall configuration diagram illustrating a state in which a differential thickness material is formed by a drive unit being displaced upward in the press molding apparatus of FIG. 1. 11 shows the vicinity of the holder part in the press molding apparatus of FIG. 1, FIG. 11A is an enlarged sectional view showing a state before the differential thickness material is held by the holder part, and FIG. 11B shows the differential thickness. It is an expanded sectional view showing the state where material was held by the holder part. It is a whole block diagram which shows the shaping | molding preparation state by which the thickness difference material is arrange | positioned between the upper mold | type and lower mold | type which comprise a metal mold | die part in the press molding apparatus of FIG. It is a whole sectional view of a press molding device concerning a prior art.

Explanation of symbols

50, 150: Press molding apparatus 54, 100, 152 ... Differential thickness materials 54a, 152a ... Thin plate portions 54b, 152b ... Thick plate portions 54c, 100c, 152c ... Joint portions 56 ... Mold portions 60, 60a, 102, 154 ... Holder part 62, 62a, 158 ... Upper mold 64 ... Base 66 ... Lower mold 68 ... Cavity 70 ... Recess 72, 72a-72e, 104, 104a-104e ... Variable holder 74, 74a, 160 ... First contact part 76 , 76a, 162 ... second contact portion 80, 106 ... variable block 90, 108, 156 ... holding block

Claims (4)

By applying pressure to the differential thickness plate where the plate thickness has partially changed, in the differential thickness material molding die used in the press molding apparatus for molding the workpiece,
A first mold that is displaced along the axial direction under the drive action of the drive unit in the press molding apparatus;
A second mold disposed at a position facing the first mold;
A holding mechanism that faces the differential thickness material and is capable of holding the differential thickness material with respect to either the first mold or the second mold,
With
The holding mechanism is provided along the longitudinal direction of the differential thickness material, and holds a constant plate thickness portion in the differential thickness material; and
A differential-thickness material molding die having a second thickness-holding portion adjacent to the first holding portion and holding the thickness-change portion where the thickness changes in the differential-thickness material. In the mold for forming a differential thickness material according to claim 1,
The first and second holding portions include a holding body that can contact the differential thickness material,
Biasing means for biasing the holding body toward the differential thickness material side;
A die for forming a differential thickness material, comprising: The mold for forming a differential thickness material according to claim 2,
The holding body of the second holding portion is formed with a die for forming a differential thickness material, wherein an end surface in contact with the differential thickness material is formed corresponding to a shape of the plate thickness changing portion of the differential thickness material. The differential thickness material molding die according to claim 2 or 3,
The holding body of the second holding unit is set to have a width dimension along a longitudinal direction of the differential thickness material that is set smaller than a width dimension of the holding body in the first holding unit. Mold for molding.

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