JP2014091140A - Method for manufacturing high strength pressed component and press die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a high strength pressed component, capable of improving a fatigue strength by reliably coining a plate end of a sidewall flange without increasing a production cost and constraints in the production facilities, and a press die for use in the manufacturing method.SOLUTION: A method for manufacturing a high strength pressed component is characterized by: sandwiching a steel plate Z1 punched in a deployed shape with bending dies 12, 22 and bending blades 13, 23 having a concave-shaped molding part on the whole, and a bending punch 11 having a convex-shaped forming part; bending the steel plate substantially in a U-shape cross section; and then inserting a plate end Z2S of a sidewall flange in the substantially U-shaped cross section into a recessed groove 14m of a coining blade 14 to perform coining. The bending blades 13, 23 are brought into abutment with the plate end Z2S during the bending, and the bending blades 13, 23 are moved in the direction separating from the coining blade 14 before the coining.

Description

  The present invention relates to a method for manufacturing a high-strength press part of an automobile and a press die. In particular, the present invention relates to a manufacturing method in which bending and coining of high-strength press parts are performed with a single press die, and a press die used in the manufacturing method.

  In general, for high-strength press parts used for automobile chassis parts, it is important to ensure fatigue resistance against repeated loads received from wheels during running. Therefore, for example, for a high-strength press part having a long U-shaped cross section, such as a torsion beam in a torsion beam type rear suspension (see FIG. 1), a steel plate is punched into a developed shape in advance, A manufacturing method is known in which the developed shape steel plate is bent into a substantially U shape, and then the end portion of the side wall flange in the bent product is coined to improve the fatigue resistance (for example, (See Patent Documents 1 and 2).

For example, Patent Document 1 discloses a method of performing bending and coining in separate press dies and separate steps for a torsion beam having a substantially U-shaped cross section with a long object (FIG. 15). , See FIG. That is, as shown in FIG. 15, in the press mold 210, a punched shape is punched between the convex portion 211 </ b> P of the lower die punch 211 and the concave portion 212 </ b> D of the upper die 212 that matches the substantially U shape of the torsion beam. The upper die 212 is lowered in the direction of the arrow P1 and bent while sandwiching the steel plate W1. Then, as shown in FIG. 16, in the press mold 220, after setting the bent product W2 on the upper surface 223P of the punch 223 floated via the cushion pin 222, the upper die 224 is moved in the direction of the arrow P2. The punch 223 is lowered by the lower surface 224D of the upper die 224. And the plate | board edge part W2E1, W2E2 of the side wall flange in the bending processed goods W2
Is inserted into the concave grooves 221M1 and 221M2 of the coining blade 221M for coining.

According to the manufacturing method described in Patent Document 1, a bending press mold 210 and a coining press mold 220 are separately required. Even if it exists, the recessed part 212D of the upper die 212 in the press die 210 for bending is extended downward to increase the amount of biting of the bending blade 212B, thereby preventing warping of the flange tip after bending. Can do. Therefore, when performing the coining process, the plate edge portions W2E1 and W2E2 of the side wall flange at the portion where the stretch flange is formed by the bending process can be reliably inserted and pressed into the concave grooves 221M1 and 221M2 of the coining blade 221M. . Therefore, the tensile residual stress at the end of the side wall flange is increased by bending, and the tensile residual stress is reduced by reliably performing coining at locations where the plate thickness decreases and fatigue strength decreases. Alternatively, the fatigue strength can be improved by changing to the compressive residual stress and increasing the plate thickness (thickening).

  On the other hand, Patent Document 2 discloses a method in which bending and coining are performed in the same press mold and in the same process for an intermediate beam that is also a long object and has a substantially U-shaped cross section ( See FIG. That is, as shown in FIG. 17, the bending process and the coining process are performed in the same process using one molding apparatus 300 including a bending die 312, a bending punch 311, and a coining blade 314. A bending portion 312D having substantially the same shape as the outer shape of the intermediate beam is formed on the lower surface of the bending die 312 in the forming apparatus 300, and a guide portion (bending blade) 312G having a predetermined radius is provided near the opening of the bending portion 312D. Is formed. Further, the bending punch 311 is attached to a cushion pin 313 supported so as to be movable up and down with respect to the lower mold 315. Further, a bending portion 311P having substantially the same shape as the inner shape of the intermediate beam is formed on the upper surface of the bending punch 311. The coining blade 314 is placed on the lower mold 315 and has a through-hole through which the cushion pin 313 is inserted. The cushion pin 313 is urged so as to elastically project the bending punch 311 toward the bending die 312 by cushion means (not shown) of the press facility.

  In the forming apparatus 300, with the upper die 316 and the lower die 315 separated from each other, the steel plate V1 punched into a developed shape is disposed between the bending die 312 and the bending punch 311, and the upper die 316 is moved to the arrow P3. Descend in the direction of. Initially, the steel plate V1 is sandwiched between the bending portion 312D of the bending die 312 and the bending portion 311P of the bending punch 311 and bent so as to be bent in the width direction (left side in FIG. 17). When the upper die 316 is further lowered in the direction of the arrow P4, the plate end V2S of the side wall flange of the bent product V2 comes into contact with the coining blade 314 and is coined (right side in FIG. 17). The coined plate end portion V3C has improved surface roughness, increased plate thickness, and conversion from tensile residual stress to compressive residual stress, thereby improving fatigue strength.

JP 2000-52733 A JP 2001-225111 A

However, the manufacturing methods of Patent Documents 1 and 2 have the following problems.
That is, in the manufacturing method of Patent Document 1, the press mold 210 for bending and the press mold 220 for coining are required separately, so that the manufacturing cost of the press mold increases and at the same time the press mold There were problems that production costs and restrictions on production facilities increased, such as the need for multiple press facilities for attaching the mold.
In the manufacturing method of Patent Document 2, a bending portion 312D having substantially the same shape as the outer shape of the intermediate beam is formed on the lower surface of the bending die 312. A guide portion having a predetermined radius is provided near the opening of the bending portion 312D. Since the (bending blade) 312G is formed, the coining blade 314 must have a structure that does not interfere with the bending portion 312D and the guide portion (bending blade) 312G of the bending die 312. Specifically, the upper end 314T of the coining blade 314 can be formed with a flat surface that only abuts the front end surface of the plate end portion V2S of the side wall flange, but the concave groove 221M1 in the coining blade 221M of Patent Document 1 is used. Like 221M2, the recessed groove into which the plate end portion V2S of the flange is inserted cannot be formed. Therefore, only the leading end surface of the flange plate end V2S is coined (also referred to as “flat coining”) by the flat surface formed on the upper end 314T of the coining blade 314. In such flat coining that crushes only the front end surface, the plate end V2S buckles during coining, or a part of the plate end V2S during the coining process causes a gap between the bending die 312 and the coining blade 314, It flows into the gap between the bending punch 311 and the coining blade 314, and a burr-like protrusion (maklet) is generated at the plate end V2S, or a coining process (“" There is a problem that the shape necessary for the plate end V2S and sufficient compressive residual stress cannot be applied.

  The present invention has been made to solve the above-mentioned problems, and improves the fatigue strength by reliably coining the plate end portion of the side wall flange without increasing the production cost and restrictions on the production equipment. An object of the present invention is to provide a method for producing a high-strength press part capable of achieving the above and a press die used in the production method.

In order to solve the above-described problems, a method for manufacturing a high-strength press part according to the present invention has the following configuration.
(1) A steel sheet punched into a developed shape is sandwiched between a bending die and a bending blade having a concave shaped portion as a whole and a bending punch having a convex shaped portion and bent into a substantially U-shaped cross section. After that, it is a manufacturing method of a high-strength press part for coining by inserting the plate end portion of the side wall flange in the substantially U-shaped cross section into the concave groove of the coining blade,
The bending blade is brought into contact with the plate end during the bending process, and the bending blade is moved away from the coining blade before the coining process.

In the invention of (1), the bending blade is brought into contact with the plate edge during bending, and the bending blade is moved away from the coining blade before coining. It is possible to prevent warping (spring back) of the plate edge by regulating, and before the coining after bending, the bending blade is separated from the coining blade and the plate edge is placed in the groove of the coining blade. It can be surely inserted. That is, the bending edge is pressed against the bending punch by the bending blade by bringing the bending blade into contact with the edge of the plate at the time of bending, for example, warping of the plate edge (spring Back) can be regulated. In addition, since the bending blade is moved in a direction away from the coining blade before coining after bending, the coining blade and the bending blade do not interfere during coining, and the plate edge portion is in the concave groove of the coining blade. It can be inserted securely and coined. Therefore, the bending process and the coining process (particularly, R coining) of the high-strength press part formed into a substantially U-shaped cross section can be reliably performed using one press mold.
Therefore, according to the invention of (1), the fatigue strength of the high-strength press part is improved by reliably coining the plate end portion of the side wall flange without increasing the production cost and the restrictions on the production equipment. be able to.

(2) In the method for producing a high-strength press part described in (1),
After the bending blade is moved and before the coining process, the coining blade is moved in a direction close to the bending punch, and the plate end portion is inserted into the concave groove.

In the invention of (2), since the coining blade is moved in the direction close to the bending punch after the bending blade is moved and before the coining process, the end of the plate is inserted into the groove, so that the bending punch is raised and lowered. Without any problem, coining can be performed after the end of the plate has been securely inserted into the groove. For example, as in the method of Patent Document 2, it is not necessary to attach the bending punch to the cushion pin, raise the bending punch during bending, and lower the bending punch during coining. For this reason, bending punches that process the entire shape range of high-strength press parts can be fixed to, for example, the lower mold, and a coining blade that can be generally limited to a partial range such as a stretch flange forming part is reduced in size. Can be moved. Therefore, the press die structure can be simplified and the die cost can be reduced. Moreover, since it is not necessary to use press equipment provided with a die cushion mechanism, restrictions on production equipment can be further reduced.
Therefore, according to the invention of (2), it is possible to further reduce the restrictions on the production cost and the production equipment, and to reliably coin the flange plate end.

(3) In the method for producing a high-strength press part described in (1) or (2),
At the lower end of the opening of the bending die, the bending blade is provided so as to be movable in a direction crossing the press direction,
After the bending process, the bending die is moved by a predetermined length in a direction away from the bending punch, and then the bending blade is moved in a direction crossing the pressing direction, and then the bending die is again moved to the bending punch. The plate edge portion is coined by moving the plate in the approaching direction.

In the invention of (3), the bending die is provided at the lower end of the opening of the bending die so as to be movable in a direction crossing the press direction, and after bending, the bending die is moved by a predetermined length in a direction away from the bending punch. Since the bending blade is moved in the direction that intersects the press direction, it is possible to move the bending blade while reducing the reaction force of the forming load accompanying the bending process that acts between the bending die and the bending blade. it can. Therefore, the force required to move the bending blade can be reduced and the bending blade moving device can be simplified. After that, the bending die is moved again in the direction close to the bending punch to coin the plate edge, so that both bending and coining can be performed by only two strokes of the same press die. Can do. Here, the predetermined length for moving the bending die can be arbitrarily selected, but it is not necessarily required to be the length for moving from the bottom dead center to the top dead center of the press facility. When the bending die is not moved from the bottom dead center to the top dead center of the press facility, the stroke length for moving the bending die again in the direction close to the bending punch can be reduced, which contributes to shortening of the cycle time.
As a result, it is possible to reduce the mold cost required for manufacturing the press mold and improve the press productivity.
Therefore, according to the invention of (3), restrictions on the production cost and production equipment can be further reduced, and the plate end portion of the flange can be reliably coined.

(4) In the method for producing a high-strength press part described in (1) or (2),
The bending die includes a nest having a concave shaped portion that abuts on the convex portion in the substantially U-shaped cross section,
After the bending process, the bending die and the bending blade are moved by a predetermined length in a direction away from the bending punch, and then only the insert is moved in a direction close to the bending punch, and then the bending die. In addition, the edge of the plate is coined by moving the bending blade again in the direction approaching the bending punch.

In the invention of (4), the bending die is provided with a nest having a concave shaped portion that comes into contact with the convex portion in the substantially U-shaped cross section, and the bending die and the bending blade are bent and punched after the bending process. After moving a predetermined length in the separating direction, only the insert is moved in the direction close to the bending punch, so the reaction force of the forming load accompanying the bending process acting on the insert is reduced, and the insert Can be moved. Therefore, the force required to move the nest can be reduced, and the nest moving device can be simplified. After that, the bending die and the bending blade are moved again in the direction close to the bending punch to coin the plate end, so that both the bending and coining processes can be performed with only two strokes of the same press die. It can be performed. Here, the distance for moving the bending die and the bending blade in the direction close to the bending punch again is the distance for moving the bending die and the bending blade away from the bending punch after the bending process. It is the length obtained by subtracting the distance to move in the direction closer to. Therefore, when the bending die and the bending blade are moved again in the direction close to the bending punch, the insert is moved to a position close to the bending punch in advance. The plate edge is coined by pressing the convex part in the U-shaped cross section. Accordingly, interference between the bending blade and the coining blade can be avoided when coining the end portion of the plate. In addition, according to this method, the stroke length which moves a bending die and a bending blade again in the direction which adjoins a bending punch can be reduced, and it can contribute to shortening of cycle time.
As a result, it is possible to reduce the mold cost required for manufacturing the press mold and improve the press productivity.
Therefore, according to the invention of (4), it is possible to further reduce the restrictions on the production cost and the production equipment, and to reliably coin the flange plate end.

In order to solve the above-described problems, a press die used in the method for manufacturing a high-strength press part according to the present invention has the following configuration.
(5) Bending dies and bending blades having a concavely shaped molded part as a whole and sandwiching a steel sheet punched into a developed shape and bending it into a substantially U-shaped cross section; a bending punch having a convex shaped part; A press die used in a method of manufacturing a high-strength press part comprising a coining blade having a concave groove for coining by inserting a plate end of a side wall flange in the substantially U-shaped cross section,
The bending blade can be brought into contact with the plate end during the bending process, and the bending blade can be moved away from the plate end before the coining process.

In the invention of (5), the bending blade can be brought into contact with the plate end during bending, and the bending blade can be moved away from the plate end before coining. The bending blade can be controlled to prevent warping of the plate edge (spring back), and the bending blade is separated from the coining blade before coining after the bending process, so that it is in the concave groove of the coining blade. A board edge part can be inserted reliably. That is, the bending edge is pressed against the bending punch by the bending blade by bringing the bending blade into contact with the edge of the plate at the time of bending, for example, warping of the plate edge (spring Back) can be regulated. In addition, since the bending blade is moved in a direction away from the coining blade before coining after bending, the coining blade and the bending blade do not interfere during coining, and the plate edge portion is in the concave groove of the coining blade. It can be surely inserted. Therefore, the bending process and the coining process (particularly, R coining) of the high-strength press part formed into a substantially U-shaped cross section can be reliably performed using one press mold.
Therefore, according to the invention of (5), the fatigue strength of the high-strength press parts can be improved by reliably coining the plate end of the flange without increasing the production cost and the restrictions on the production equipment. Can do.

(6) In a press die used in the method for producing a high-strength press part described in (5),
The coining blade is moved in a direction close to the bending punch after the bending process, so that the plate end can be inserted into the concave groove.

In the invention of (6), the coining blade moves in the direction close to the bending punch after bending, and the end of the plate can be inserted into the groove, so that the bending punch can be reliably moved up and down. Coining can be performed after inserting the plate end of the side wall flange into the groove. For example, like the press die of Patent Document 2, the bending punch may be attached to the cushion pin, the bending punch may be raised during the bending process, and the bending punch may not be lowered during the coining process. For this reason, bending punches that process the entire shape range of high-strength press parts can be fixed to, for example, the lower mold, and a coining blade that can be generally limited to a partial range such as a stretch flange forming part is reduced in size. Can be moved. Therefore, the press die structure can be simplified and the die cost can be reduced. Moreover, since it is not necessary to use press equipment provided with a die cushion mechanism, restrictions on production equipment can be further reduced. In addition, when a coining blade moves to the direction close | similar to a bending punch after a bending process, it is preferable that the upper surface of a coining blade and the lower surface of a bending punch closely_contact | adhere. This is because the crack at the end of the plate due to coining can be reduced.
Therefore, according to the invention of (6), it is possible to further reduce the restrictions on the production cost and production equipment, and to reliably coin the flange plate end.

(7) In a press die used in the method for producing a high-strength press part described in (5) or (6),
The lower end of the opening of the bending die is provided with the bending blade movably in a direction crossing the press direction.

In the invention of (7), since the bending blade is provided at the lower end of the opening of the bending die so as to be movable in the direction intersecting the pressing direction, the slide ram of the press equipment is raised by a predetermined length, and the bending die and the bending blade are provided. The bending blade can be easily moved by reducing the reaction force of the molding load that accompanies the bending process between the two. Therefore, the force required to move the bending blade can be reduced and the bending blade moving device can be simplified. After that, if the slide ram of the press facility is lowered again and the end portion of the plate is coined, both bending and coining can be performed only by two strokes of the same press die. As a result, it is possible to reduce the mold cost required for manufacturing the press mold and improve the press productivity.
Therefore, according to the invention of (7), the plate cost of the flange can be reliably coined by further reducing the production cost and restrictions on the production equipment.

(8) In a press die used in the method for producing a high-strength press part described in (5) or (6),
The bending die includes a nest having a concave shaped portion that abuts on a convex portion in the substantially U-shaped cross section, and only the nest is movable in a direction close to the bending punch. And

In the invention of (8), the bending die is provided with a nest having a concave shaped part that abuts on the convex part in the substantially U-shaped cross section, and only the nest is moved in a direction close to the bending punch. Since the slide ram of the press facility is raised by a predetermined length to reduce the reaction force of the forming load accompanying the bending process that acts on the insert, only the insert can be moved easily. Therefore, the force required to move the nest can be reduced, and the nest moving device can be simplified. After that, if the slide ram of the press facility is lowered again and the end portion of the plate is coined, both bending and coining can be performed only by two strokes of the same press die. As a result, it is possible to reduce the mold cost required for manufacturing the press mold and improve the press productivity.
Therefore, according to the invention of (8), it is possible to further reduce the restrictions on the production cost and production equipment, and to reliably coin the plate end of the flange.

  According to the present invention, a method for manufacturing a high-strength press part capable of improving fatigue strength by reliably coining the plate end portion of the flange without increasing production cost and production facility restrictions, and A press die used in the manufacturing method can be provided.

It is a perspective view of the high strength press component manufactured by the manufacturing method concerning this embodiment. It is AA sectional drawing in the high intensity | strength press part shown in FIG. FIG. 3 is a detailed view of part C shown in FIG. 2. It is typical sectional drawing of the press die in the middle of a bending process about the 1st Example which concerns on this embodiment. It is a typical sectional view of a press metallic mold at the time of completion of bending processing about the 1st example. FIG. 6 is a schematic cross-sectional view of the press die when the bending die is raised after the bending process is completed and the bending blade is moved in the first embodiment. It is a typical sectional view of a press metallic mold when a coining blade is moved in the direction which adjoins a bending punch after a bending blade movement about the 1st example. It is a typical sectional view of a press metallic mold at the time of completion of coining about the 1st example. It is typical sectional drawing of the press die in the middle of a bending process about the 2nd Example which concerns on this embodiment. It is a typical sectional view of a press metallic mold at the time of completion of bending processing about the 2nd example. It is a typical sectional view of a press die when a bending die is raised and bending blade is moved after the bending process is completed in the second embodiment. About the 2nd Example, it is a typical sectional view of a press metallic mold when an insert is moved in the direction which adjoins a bending punch after a bending blade movement. It is a typical sectional view of a press metallic mold when a coining blade is moved in the direction which adjoins a bending punch after nest movement about the 2nd example. It is a typical sectional view of a press metallic mold at the time of completion of coining about the 2nd example. It is a typical sectional view of a press metallic mold at the time of completion of bending about a conventional bending method in high strength press parts. It is typical sectional drawing of the press die at the time of completion of coining about the conventional coining processing method in a high intensity | strength press part. It is each typical sectional drawing of the press die at the time of completion of a bending process and a coining process about the same metal mold | die processing method of the conventional bending process and coining process in a high intensity | strength press part.

  Next, a manufacturing method of a high-strength press part which is an embodiment according to the present invention and a press die used in the manufacturing method will be described in detail with reference to the drawings. First, after briefly explaining the structure of the high-strength press part according to the present embodiment, the high-strength press part is used by using the press dies of the first and second examples according to the present embodiment. The manufacturing method and the operation of the press mold will be described in detail.

<Structure of high strength pressed parts>
First, the structure of a high-strength press part according to the present embodiment will be briefly described with an example of a torsion beam used for a torsion beam type rear suspension of an automobile. FIG. 1 is a perspective view of a high-strength press part manufactured by the manufacturing method according to the present embodiment. FIG. 2 is a cross-sectional view taken along line AA in the high-strength press part shown in FIG. FIG. 3 is a detailed view of the part C shown in FIG.

  As shown in FIGS. 1 and 2, a torsion beam 10, which is a high-strength press part, includes a convex portion 1 that bulges toward the rear of the vehicle, and side wall flange portions 2 and 3 that are bent forward from the convex portion 1 to the vehicle. Is a long press part that forms a substantially U-shaped cross section as a whole. Here, the arrow X indicates the vehicle width direction, the arrow Y indicates the vehicle vertical direction, and the arrow Z indicates the vehicle longitudinal direction. The vicinity of both ends in the vehicle width direction of the convex portion 1 is curved so as to incline toward the rear of the vehicle. Further, bifurcated tongue pieces 4 and 5 are formed at both ends of the side wall flange portions 2 and 3 in the vehicle width direction. The tongue pieces 4 and 5 are joined to a trailing arm extending in the vehicle front-rear direction. The front end of the trailing arm is connected to the vehicle body so as to be swingable. The torsion beam 10 joined to the trailing arm is transmitted with vibrations and torsional moments from the road surface via coil springs, shock absorbers and the like that suspend the axle. In FIG. 1, the trailing arm, the axle, the coil spring, and the like are not shown because they are complicated.

  As the material of the torsion beam 10, for example, a high-tensile steel plate having a plate thickness of about 6 mm and a tensile strength of about 600 MPa is punched into a developed shape and used. Further, the steel sheet punched into a developed shape is bent into a substantially U-shaped cross section by a press die. When the steel plate is bent into a substantially U-shaped cross section, when the convex portion 1 is curved, the end portions of the side wall flange portions 2 and 3 are stretched and flange-formed (range of B1, B2, B3, and B4). There is. In the plate end portions 21 and 31 forming the distal end side of the side wall flange portions 2 and 3 which are stretch flange forming, the plate thickness after bending is reduced from the original material plate thickness, and the tensile internal stress is accumulated. Therefore, the fatigue strength tends to decrease.

  Therefore, as shown in FIG. 3, as shown in FIG. 3, by performing the coining process after bending the plate end portions 21 and 31 at the locations (in the range of B1, B2, B3, and B4) where the stretch flange molding is performed. In addition, the plate thicknesses of the plate end portions 21 and 31 are increased (increased) from the material plate thickness, and burrs and the like due to punching processing remaining on the front end surfaces of the plate end portions 21 and 31 are removed to form R or chamfers at both ends of the front end. And the tip is formed on a smooth flat surface. In FIG. 3, the cross-sections of the coined plate end portions 21 and 31 are enlarged, but the raw steel plate Z1 is indicated by a two-dot chain line, and the plate end portions 21 and 31 after coining are indicated by a solid line. . The side surfaces 21a, 21e, 31a, 31e in the vehicle vertical direction at the plate end portions 21, 31 are expanded by about 5 to 10% from the material side surfaces. The front end surfaces 21c and 31c in the plate end portions 21 and 31 are crushed by about 20 to 30% of the material plate thickness. Further, R or chamfering of about 0.4 to 2 mm is formed at both corners 21b, 21d, 31b, 31d at the plate end portions 21, 31.

<First embodiment>
Next, with respect to the first example according to the present embodiment, a manufacturing method for performing bending and coining of a high-strength press part with the same press mold will be described in detail. In addition, the operation of the press die will be described in detail. FIG. 4 shows a schematic cross-sectional view of a press die in the middle of bending for the first example according to the present embodiment. FIG. 5 shows a schematic cross-sectional view of a press die at the time of completion of the bending process in the first embodiment. FIG. 6 shows a schematic cross-sectional view of the press die when the bending die is raised and the bending blade is moved after the bending process is completed in the first embodiment. FIG. 7 is a schematic cross-sectional view of the press die when the coining blade is moved in the direction close to the bending punch after the bending blade is moved in the first embodiment. FIG. 8 shows a schematic cross-sectional view of the press die when the coining process is completed in the first embodiment.

  As shown in FIG. 4, the press die 100 according to the first embodiment includes a bending punch 11, a bending die 12, a bending blade 13, a coining blade 14, a bending blade moving device 15, and a coining blade moving device. 16, a coining table 17, a lower mold body 18, and an upper mold body 19. FIG. 4 illustrates a state during the bending process in which the upper die main body 19 is lowered in the direction of the arrow Q1.

The lower mold main body 18 and the upper mold main body 19 are mold bases having U-grooves to be attached to a press facility and provided with vertical guide portions.
The bending punch 11 is fixed to the upper end of the lower mold body 18. However, the lower end 11b of the bending punch 11 is formed at a height that does not interfere with the coining blade 14 at the time of coining, at least in the range where coining is performed.
A convex shaped portion 11 a is formed on the upper surface of the bending punch 11. The convex shaped portion 11 a has substantially the same shape as the plate inner shape of the convex portion 1 and the side wall flange portions 2 and 3 in the torsion beam 10. A steel plate (material) Z1 punched into a developed shape is placed on the convex shaped portion 11a.

The bending die 12 is fixed to the lower end of the upper die body 19.
A concave shaped part 12 a is formed on the lower surface of the bending die 12. A bending blade 13 is provided at the opening lower end 12b of the bending die 12 so as to be movable in a direction crossing the pressing direction. The opening lower end 12b of the bending die 12 is a lower end formed in the horizontal direction adjacent to the concave shaped portion 12a. The bending blade 13 is formed with a molding portion 13a that comes into contact with the plate end portion Z2S. A predetermined angle R is formed at the lower end of the molding portion 13a. In addition, the shape of the forming portion 12a of the bending die 12 and the shape of the forming portion 13a of the bending blade 13 are substantially the same as the plate outer shape of the convex portion 1 and the side wall flange portions 2 and 3 in the torsion beam 10. The molding part 12a of the bending die 12 and the molding part 13a of the bending blade 13 form a concave molding part that is continuous as a whole.

  The bending blade 13 has a predetermined height, and an upper end 13e and a lower end 13b are formed in parallel. The bending blade 13 can move outward in the horizontal direction, with the upper end 13 e of the bending blade 13 being in sliding contact with the opening lower end 12 b of the bending die 12. A bending blade moving device 15 is connected to the outer side end 13 c of the bending blade 13. The bending blade moving device 15 is a simple driving device using an air cylinder or the like as a driving source.

  The coining blade 14 is a substantially rectangular block body. The upper end 14t of the coining blade 14 is formed with a concave groove 14m into which a plate end Z2S to be coined is inserted. R or chamfering is formed at both lower corners of the concave groove 14m. The coining blade 14 is divided in the vertical direction at the center of the lower end of the concave groove 14m. The lower end of the coining blade 14 is fitted to a rectangular coining table 17.

  The coining table 17 is placed on the upper end of the lower mold body 18. A coining blade moving device 16 is disposed at the upper end of the lower mold body 18 adjacent to the coining table 17. The coining blade moving device 16 is a simple driving device that moves a spacer block having a parallel upper end 16b and a lower end 16c in a horizontal direction by a driving source such as an air cylinder. An inclined surface 16 a is formed on the side of the spacer block adjacent to the coining table 17. The inclined surface 16a serves as a guide surface that moves the coining table 17 up and down.

  First, as shown in FIG. 4, when the upper die body 19 is lowered in the direction of the arrow Q <b> 1, the steel plate (material) Z <b> 1 placed on the forming portion 11 a of the bending punch 11 is bent with the forming portion 12 a of the bending die 12. It is bent downward by the forming part 13 a of the blade 13 and is bent along the forming part 11 a of the bending punch 11.

  Further, as shown in FIG. 5, when the upper die body 19 is lowered in the direction of the arrow Q2, the steel plate (material) Z1 is formed with the forming portion 11a of the bending punch 11, the bending die 12, and the forming portion 12a of the bending blade 13. 13b, the bent product Z2 is frozen (plastically deformed) and the bending process is completed. At this time, the lower end 13b of the bending blade 13 descends below the plate end Z2S of the bent product Z2 and comes close to the upper end 14t of the coining blade 14, but there is no interference. The plate end Z2S of the bent product Z2 is in contact with the forming portion 13a of the bending blade 13, and warpage (spring back) to the outside of the plate is restricted.

  Next, as shown in FIG. 6, the upper die body 19 is raised by a predetermined length in the direction of the arrow Q3. When the upper die main body 19 is raised by a predetermined length, a gap is generated on the contact surface between the bending die 12 and the forming portions 12a and 13a of the bending blade 13 and the bent product Z2. Therefore, the reaction force of the forming load accompanying the bending process that acts on the bending die 12 and the bending blade 13 is reduced. As a result, the sliding contact resistance between the opening lower end 12b of the bending die 12 and the upper end 13e of the bending blade 13 is also reduced. Therefore, after the upper die body 19 has been raised by a predetermined length in the direction of the arrow Q3, the bending blade 13 is moved in the direction of the arrow Q4 by the bending blade moving device 15. The bending blade 13 is separated to a position where it does not interfere with the coining blade 14 and the coining table 17 during coining. Here, the predetermined length by which the upper die body 19 rises in the direction of the arrow Q3 is such that the reaction force of the molding load accompanying the bending process acting between the bending die 12 and the bending blade 13 can be made substantially zero. Length is preferred. The predetermined length depends on the material, plate thickness, cross-sectional shape, etc. of the high-strength press part, but is about 10 mm, for example.

  Next, as shown in FIG. 7, the spacer block of the coining blade moving device 16 is moved in the direction of the arrow Q5. The lower end 17a of the coining table 17 is pushed up by the inclined surface 16a and the upper end 16b of the spacer block, and the coining blade 14 fitted to the coining table 17 is moved in the direction close to the bending punch 11 (direction of arrow Q6). When the upper end 14t of the coining blade 14 comes into contact with the lower end 11b of the bending punch 11, the plate end Z2S of the bent product Z2 is inserted into the concave groove 14m of the coining blade 14. When the plate end Z2S of the bent product Z2 is inserted into the concave groove 14m of the coining blade 14, the bent product Z2 slightly rises, and a gap is formed between the molded part 11a of the bending punch 11. The In the bent product Z2, a gap is also formed between the bending die 12 and the forming portion 12a of the bending die 12. At this time, a gap is also formed between the forming portion 13a of the bending blade 13 and the side wall 17b of the coining table 17 so as not to interfere.

Next, as shown in FIG. 8, the upper mold body 19 is lowered again in the direction of the arrow Q7. When the upper die body 19 is lowered again, the bent product Z2 is sandwiched between the molded portion 12a of the bending die 12 and the molded portion 11a of the bending punch 11, and at the same time, the plate end Z2S of the bent product Z2 is It is pressed into the concave groove 14 m of the coining blade 14. As a result, the plate end Z2S of the bent product Z2 is coined. That is, as shown in FIG. 3, the plate end Z2S of the bent product Z2 has a plate thickness increased (increased) than the material plate thickness, and burrs or the like due to punching remaining on the front end surface of the plate end Z2S are generated. By removing, R or chamfering is formed at both corners of the tip, and the tip is formed on a smooth flat surface.
As described above, according to the first embodiment, a single press mold 100 is used to perform bending and coining of a high-strength press product while the upper die body 19 is moved up and down twice. be able to.

<Second embodiment>
Next, regarding the second example according to the present embodiment, a manufacturing method for performing bending and coining of a high-strength press part with the same press mold will be described in detail. In addition, the operation of the press die will be described in detail. FIG. 9 shows a schematic cross-sectional view of a press die in the middle of bending for the second example according to the present embodiment. FIG. 10 shows a schematic cross-sectional view of the press die at the time of completion of the bending process in the second embodiment. FIG. 11 shows a schematic cross-sectional view of the press die when the bending die is raised and the bending blade is moved after the bending process is completed in the second embodiment. FIG. 12 shows a schematic cross-sectional view of the press die when the insert is moved in the direction close to the bending punch after the bending blade is moved in the second embodiment. FIG. 13 shows a schematic cross-sectional view of the press die when the coining blade is moved in the direction close to the bending punch after the nested movement in the second embodiment. FIG. 14 shows a schematic cross-sectional view of a press die at the time of completion of coining in the second embodiment.

As shown in FIG. 9, the press die 101 of the second embodiment includes a bending punch 11, a bending die 22, an insert 221, a bending blade 23, an insert moving device 24, and a coining blade 14. The coining blade moving device 16, the coining table 17, the lower mold body 18, and the upper mold body 19 are provided. FIG. 9 illustrates a state during the bending process in which the upper die body 19 is lowered in the arrow Q1 direction.
The press die 101 of the second embodiment is different from the press die 100 of the first embodiment only in the bending die 22, the insert 221, the bending blade 23, and the insert moving device 24. Yes, others are common. Therefore, the bending punch 11, the coining blade 14, the coining blade moving device 16, the coining table 17, the lower mold body 18, and the upper mold body 19 common to the press mold 100 of the first embodiment are as follows. The same reference numerals as those of the press die 100 of the first embodiment are attached, and the description thereof is omitted in principle. The differences will be described in detail below.

  As shown in FIG. 9, the bending die 22 is fixed to the lower end of the upper die body 19. A concave shaped portion 22 a (not shown) is formed on the lower surface of the bending die 22. However, the bending die 22 is provided with a nest 221 that abuts on a convex portion in a substantially U-shaped cross section of the torsion beam 10 at least in a coining process range (B1, B2, B3, and B4 ranges). A concave shaped part 221 a is formed on the lower surface of the insert 221.

  Bending blades 23 are disposed on the left and right sides of the insert 221. An upper end 23 c of the bending blade 23 is fixed to the upper mold body 19. The bending blade 23 is formed with a molding portion 23a that comes into contact with the plate end portion Z2S. A sliding contact portion 23e is formed above the forming portion 23a of the bending blade 23 so as to be in sliding contact with the side end 221b of the insert 221. A predetermined angle R is formed at the lower end of the forming portion 23 a of the bending blade 23. The lower end 23b of the bending blade 23 is formed in the horizontal direction. Further, the shape of the forming portion 221 a of the insert 221 and the shape of the forming portion 23 a of the bending blade 23 are substantially the same as the plate outer shape of the convex portion 1 and the side wall flange portions 2 and 3 in the torsion beam 10. The molding part 22 a of the bending die 22, the molding part 221 a of the insert 221, and the molding part 23 a of the bending blade 23 form a continuous concave molding part.

  The insert 221 is movable in a direction close to the bending punch 11. A telescoping device 24 is disposed adjacent to the bending blade 23 at the lower end of the upper body 19. The telescoping device 24 is a simple drive device that moves a spacer block having parallel upper and lower ends 24c and 24b back and forth in the horizontal direction by a drive source such as an air cylinder. An inclined surface 24 a is formed on the side of the spacer block adjacent to the bending blade 23. The inclined surface 24a serves as a guide surface for raising and lowering the insert 221. The bending blade 23 is formed with a through hole 23f in order to secure a passage through which the spacer block moves back and forth.

  First, as shown in FIG. 9, when the upper die body 19 is lowered in the direction of the arrow Q1, the steel plate (material) Z1 placed on the forming portion 11a of the bending punch 11 is formed with the forming portion 22a of the bending die 22; The molded portion 221 a of the insert 221 and the molded portion 23 a of the bending blade 23 are bent downward and are bent along the molded portion 11 a of the bending punch 11.

  Further, as shown in FIG. 10, when the upper die main body 19 is lowered in the direction of the arrow Q <b> 2, the steel plate (material) Z <b> 1 is formed by the forming part 11 a of the bending punch 11, the bending die 22, the insert 221, and the bending blade 23. The bent product Z2 is sandwiched between the molding portions 22a, 221a, and 23a, and the bent product Z2 is frozen in shape (plastically deformed) to complete the bending process. At this time, the lower end 23b of the bending blade 23 descends below the plate end Z2S of the bent product Z2 and comes close to the upper end 14t of the coining blade 14, but there is no interference. The plate end Z2S of the bent product Z2 is in contact with the forming portion 23a of the bending blade 23, and warpage (spring back) to the outside of the plate is restricted.

  Next, as shown in FIG. 11, the upper die body 19 is raised by a predetermined length in the direction of the arrow Q8. When the upper die body 19 is raised by a predetermined length in the direction of the arrow Q8, the bending blade 23 is separated to a position where the lower end 23b of the bending blade 23 does not interfere with the upper end 14t of the coining blade 14 during coining. Here, the predetermined length by which the upper die body 19 rises in the direction of the arrow Q8 is a position where the lower end 23b of the bending blade 23 is separated from the plate end Z2S of the bent product Z2 from the lowered position when the bending is completed. The distance traveled to is preferred. The predetermined length is, for example, about 90 to 100 mm, although it depends on the material, plate thickness, cross-sectional shape, etc. of the high-strength press part. When the upper die body 19 is raised by a predetermined length, a gap is generated on the contact surface between the bending die 22, the insert 221, and the molding portions 22a, 221a, 23a of the bending blade 23 and the bent product Z2. Further, the bent product Z <b> 2 slightly rises, and a gap is also formed between the bent portion 11 and the molded portion 11 a. Therefore, the reaction force of the molding load accompanying the bending process which acts on the bending die 22, the insert 221 and the bending blade 23 decreases. As a result, the sliding contact resistance between the side end 221b of the insert 221 and the sliding contact portion 23e of the bending blade 23 is also reduced.

  Therefore, after the upper die body 19 has been raised by a predetermined length in the direction of the arrow Q8, as shown in FIG. 12, the spacer block of the nesting moving device 24 is moved in the direction of the arrow Q9, and the nesting 221 is moved to the arrow. Lower in the direction of Q10. The insert 221 moves to a position close to the bending punch 11.

  Next, as shown in FIG. 13, the spacer block of the coining blade moving device 16 is moved in the direction of the arrow Q11. The lower end 17a of the coining table 17 is pushed up by the inclined surface 16a and the upper end 16b of the spacer block, and the coining blade 14 fitted to the coining table 17 is moved in the direction close to the bending punch 11 (direction of arrow Q12). When the upper end 14t of the coining blade 14 comes into contact with the lower end 11b of the bending punch 11, the plate end Z2S of the bent product Z2 is inserted into the concave groove 14m of the coining blade 14. At this time, a gap is formed between the lower end 23b of the bending blade 23 and the upper end 14t of the coining blade 14 so as not to interfere during coining.

Next, as shown in FIG. 14, the upper die body 19 is lowered again in the direction of the arrow Q13. When the upper die body 19 is lowered again, the bent product Z2 is sandwiched between the molded portion 221a of the insert 221 and the molded portion 11a of the bending punch 11, and at the same time, the plate end Z2S of the bent product Z2 is It is pressed into the concave groove 14 m of the coining blade 14. As a result, the plate end Z2S of the bent product Z2 is coined. That is, as shown in FIG. 3, the plate end Z2S of the bent product Z2 has a plate thickness increased (increased) than the material plate thickness, and burrs or the like due to punching remaining on the front end surface of the plate end Z2S are generated. By removing, R or chamfering is formed at both corners of the tip, and the tip is formed on a smooth flat surface.
As described above, according to the second embodiment, a single press mold 101 is used to perform bending and coining of a high-strength press product while the upper die body 19 is moved up and down twice. be able to.

<Effect>
As described above in detail, according to the method for manufacturing a high-strength press product according to the present embodiment (first example, second example), the bending blades 13 and 23 are placed at the plate end portions during bending. Since the bending blades 13 and 23 are moved in a direction away from the coining blade 14 before coining, the plate edge Z2S is regulated by the bending blades 13 and 23 during the bending process. Warpage (spring back) can be prevented, and before the coining after bending, the bending blades 13 and 23 are separated from the coining blade 14, and the plate end Z2S is formed in the concave groove 14m of the coining blade 14. It can be surely inserted. That is, when the bending blades 13 and 23 are brought into contact with the plate end portion Z2S at the time of bending, the bent plate end portion Z2S is pressed against the bending punch 11 by the bending blades 13 and 23. Also, the warp (spring back) of the plate end Z2S can be restricted. Further, since the bending blades 13 and 23 are moved away from the coining blade 14 before the coining after the bending, the coining blade 14 and the bending blade 13, even if the bending dies 12 and 22 are lowered during the coining. 23 does not interfere, and the plate end Z2S can be reliably inserted into the concave groove 14m of the coining blade 14 for coining. Therefore, the bending process and the coining process (particularly, R coining) in the high-strength press part formed into a substantially U-shaped cross section can be reliably performed using the single press mold 100 or 101. .

Further, according to the present embodiment (first example, second example), the coining blade 14 is moved in the direction close to the bending punch 11 after the movement of the bending blades 13 and 23 and before coining. Thus, since the plate end portion Z2S is inserted into the concave groove 14m, the plate end portion Z2S can be reliably inserted into the concave groove 14m without raising and lowering the bending punch 11, and then coining can be performed. For example, as in the method of Patent Document 2 shown in FIG. 17, the bending punch 311 may be attached to the cushion pin 313, and the bending punch 311 may be raised during the bending process and the bending punch 311 may not be lowered during the coining process. Therefore, the bending punch 11 for processing the entire range of the shape of the high-strength press part can be fixed to, for example, the lower die body 18, and generally a partial range (B1, B2, B3, The coining blade 14 that can be limited to the range (B4) can be reduced in size and moved. Therefore, the press die structure can be simplified and the die cost can be reduced. Moreover, since it is not necessary to use press equipment provided with a die cushion mechanism, restrictions on production equipment can be further reduced.

Further, according to the present embodiment (first example), the opening lower end 12b of the bending die 12 is provided with the bending blade 13 so as to be movable in a direction intersecting the pressing direction, and the bending die 12 is attached after the bending process. Since the bending blade 13 is moved in a direction crossing the press direction after being raised by a predetermined length, the reaction force of the forming load accompanying the bending process acting between the bending die 12 and the bending blade 13 is reduced. The bending blade 13 can be moved. Therefore, the force required to move the bending blade 13 can be reduced, and the bending blade moving device 15 can be simplified. Moreover, since the bending die 12 is lowered again and the plate end Z2S is coined, both bending and coining can be performed only by two strokes of the same press die 100. Here, it is not always necessary to raise the bending die 12 to the top dead center. When the bending die 12 is not raised to the top dead center, the stroke length at the time of lowering again can be reduced, which can contribute to shortening the cycle time.
As a result, the die cost required for manufacturing the press die 100 can be reduced, and the press productivity can be improved. The predetermined length is preferably such a length that the reaction force of the forming load accompanying the bending process acting between the bending die 12 and the bending blade 13 can be made substantially zero. The predetermined length depends on the material, plate thickness, cross-sectional shape, etc. of the high-strength press part, but is about 10 mm, for example.

Moreover, according to this embodiment (2nd Example), the bending die 22 is equipped with the nest | insert 221 which has the concave shape formation part 221a contact | abutted to the convex-shaped part 1 in a substantially U-shaped cross section, and is bent. After the processing, the bending die 22 and the bending blade 23 are raised by a predetermined length, and then only the insert 221 is moved in the direction close to the bending punch 11, so that the reaction of the forming load accompanying the bending processing acting on the insert 221 is reduced. The insert 221 can be moved with the force reduced. Therefore, the force required to move the insert 221 can be reduced, and the insert moving device 24 can be simplified. After that, the bending die 22 and the bending blade 23 are lowered again and the plate end Z2S is coined, so that both the bending and coining can be performed only by two strokes of the same press die 101. Can do. Here, the length for lowering the bending die 22 and the bending blade 23 again is such that after the bending process, only the insert 221 is brought close to the bending punch 11 from a predetermined length for raising the bending die 22 and the bending blade 23. This is the length obtained by subtracting the length to be moved. Therefore, when the bending die 22 and the bending blade 23 are lowered again, the insert 221 is moved to a position close to the bending punch 11 in advance, so that the molding part 221a of the insert 221 is substantially U of the bent product Z2. The plate end Z2S of the bent product Z2 is coined by pressing the convex portion in the letter-shaped cross section. Therefore, interference between the bending blade 23 and the coining blade 14 can be avoided when coining the plate end Z2S. In addition, according to this method, the stroke length which lowers the bending die 22 and the bending blade 23 again can be reduced, and it can contribute to shortening of cycle time.
As a result, it is possible to reduce the mold cost required for manufacturing the press mold and improve the press productivity. The predetermined length is preferably a distance by which the lower end 23b of the bending blade 23 moves from a lowered position when the bending process is completed to a position where it is separated from the plate end Z2S of the bent product Z2. The predetermined length is, for example, about 90 to 100 mm, although it depends on the material, plate thickness, cross-sectional shape, etc. of the high-strength press part.

  Moreover, according to the press die used for the manufacturing method of the high-strength press part which concerns on other embodiment (1st Example, 2nd Example), the bending blades 13 and 23 are board edge part Z2S at the time of a bending process. Since the bending blades 13 and 23 can be moved away from the plate end Z2S before coining, the bending edge 13 and 23 regulates the plate end Z2S during the bending process. The warping (spring back) of the portion Z2S can be prevented, and the bending blades 13 and 23 are separated from the coining blade 14 before the coining processing after the bending processing, and the end of the plate ends in the concave groove 14m of the coining blade 14. Part Z2S can be inserted reliably. That is, when the bending blades 13 and 23 are brought into contact with the plate end portion Z2S at the time of bending, the bent plate end portion Z2S is pressed against the bending punch 11 by the bending blades 13 and 23. Also, the warp (spring back) of the plate end Z2S can be restricted. Further, since the bending blades 13 and 23 are moved away from the coining blade 14 before the coining after the bending, the coining blade 14 and the bending blade 13, even if the bending dies 12 and 22 are lowered during the coining. 23 does not interfere, and the plate end Z2S can be reliably inserted into the concave groove 14m of the coining blade 14 for coining. Therefore, it is possible to reliably perform the bending process in the high-strength press part 10 formed into a substantially U-shaped cross section and the coining process (particularly, R coining) of the plate end portions 21 and 31 by using one press mold. it can.

  Moreover, according to other embodiment (1st Example, 2nd Example), the coining blade 14 moves to the direction close | similar to the bending punch 11 after a bending process, and plate edge is in the concave groove 14m. Since the portion Z2S can be inserted, the plate end portion Z2S of the side wall flange can be securely inserted into the concave groove 14m without raising and lowering the bending punch 11, and then coining can be performed. For example, as in the press die of Patent Document 2 shown in FIG. 17, the bending punch 311 is attached to the cushion pin 313, the bending punch 311 is raised during the bending process, and the bending punch 311 is not lowered during the coining process. Good. Therefore, the bending punch 11 for processing the entire range of the shape of the high-strength press part can be fixed to, for example, the lower die body 18, and generally a partial range (B1, B2, B3, The coining blade 14 that can be limited to the range (B4) can be reduced in size and moved. Therefore, the press die structure can be simplified and the die cost can be reduced. Moreover, since it is not necessary to use press equipment provided with a die cushion mechanism, restrictions on production equipment can be further reduced. In addition, when the coining blade 14 moves in a direction close to the bending punch 11 after bending, it is preferable that the upper end 14t of the coining blade 14 and the lower end 11b of the bending punch 11 are in close contact with each other. This is because the crack of the plate end Z2S due to coining can be reduced.

  According to another embodiment (first example), the lower end 12b of the bending die 12 is provided with the bending blade 13 so as to be movable in a direction intersecting the pressing direction, so that the upper die body 19 is provided in a predetermined manner. The bending blade 13 can be easily moved by increasing the length and reducing the reaction force of the molding load accompanying the bending process that acts between the bending die 12 and the bending blade 13. Therefore, the force required to move the bending blade 13 can be reduced, and the bending blade moving device 15 can be simplified. Then, if the upper die body 19 is lowered again and the plate end Z2S is coined, both bending and coining can be performed only by two strokes of the same press die 100. As a result, the die cost required for manufacturing the press die 100 can be reduced, and the press productivity can be improved.

  Moreover, according to other embodiment (2nd Example), the bending die 22 is equipped with the nest | insert 221 which has the concave shape formation part 221a contact | abutted to the convex-shaped part 1 in a substantially U-shaped cross section, Since only the insert 221 can be moved in the direction close to the bending punch 11, the bending die 22 and the bending blade 23 are raised by a predetermined length, and the reaction force of the forming load accompanying the bending process that acts on the insert 221. If the number is reduced, only the insert 221 can be easily moved. Therefore, the force required to move the insert 221 can be reduced, and the insert moving device 24 can be simplified. After that, if the bending die 22 and the bending blade 23 are lowered again and the plate end Z2S is coined, both the bending and coining can be performed only by two strokes of the same press die 101. Can do. As a result, it is possible to reduce the die cost required for manufacturing the press die 101 and improve the press productivity.

The embodiment described above can be changed without changing the gist of the present invention.
(1) For example, in the said 1st Example and 2nd Example, the coining blade moving apparatus 16 is provided, and the coining blade 14 is made into the bending punch 11 after the movement of the bending blades 13 and 23 and before coining processing. A method is adopted in which the plate end Z2S is inserted into the concave groove 14m by moving in the approaching direction. However, it is not limited to this.
For example, by raising and lowering the bending punch 11 with a hydraulic cylinder or the like, the bending punch 11 is separated from the coining blade 14 before bending, and the coining blade 14 and the bending punch 11 are brought into contact before coining after bending. Thus, the plate end Z2S may be inserted into the concave groove 14m of the coining blade 14 before coining. In this case, the coining blade moving device 16 becomes unnecessary.
(2) For example, in the first embodiment and the second embodiment, the bending dies 12, 22, and the bending blades 13, 23 are disposed in the upper die body 19, and the bending punch 11 and the coining blade 14 are moved downward. The bending die 12, 22 and the bending blades 13, 23 are disposed in the lower mold body 18, and the bending punch 11 and the coining blade 14 are disposed in the upper mold body 19. It may be arranged. In any case, the bending dies 12 and 22, the bending blades 13 and 23, the bending punch 11 and the coining blade 14 can be brought close to and separated from each other, so that bending and coining can be performed with a single press die.

  INDUSTRIAL APPLICABILITY The present invention can be used particularly for a method for producing a high-strength press part of an automobile and a press die used for the method.

DESCRIPTION OF SYMBOLS 1 Convex part 2, 3 Side wall flange part 21, 31 Board edge part 10 Torsion beam (high-strength press part)
Z1 steel plate (material)
Z2 bending product Z2S bending product plate end 11 bending punch 11a bending punch forming part 12, 22 bending die 12a, 22a bending die forming part 221 insert 221a nested forming part 13, 23 bending blade 13a, 23a Molding part of bending blade 14 Coining blade 14m Concave groove of coining blade 15 Bending blade moving device 16 Coining blade moving device 17 Coining table 18 Lower mold body 19 Upper mold body 100, 101 Press mold

Claims (8)

After the steel sheet punched into a developed shape is sandwiched between a bending die and a bending blade having a concave shaped portion as a whole, and a bending punch having a convex shaped portion, and bent into a substantially U-shaped cross section, A method of manufacturing a high-strength press part that performs coining by inserting a plate end portion of a side wall flange in the substantially U-shaped cross section into a concave groove of a coining blade,
A manufacturing method of a high-strength press part, wherein the bending blade is brought into contact with the plate end during the bending process, and the bending blade is moved away from the coining blade before the coining process. In the manufacturing method of the high intensity | strength press part described in Claim 1,
A high-strength press part that moves the coining blade in a direction close to the bending punch after the movement of the bending blade and before the coining processing, and inserts the plate end into the concave groove. Manufacturing method. In the manufacturing method of the high intensity | strength press part described in Claim 1 or Claim 2,
At the lower end of the opening of the bending die, the bending blade is provided so as to be movable in a direction crossing the press direction,
After the bending process, the bending die is moved by a predetermined length in a direction away from the bending punch, and then the bending blade is moved in a direction crossing the pressing direction, and then the bending die is again moved to the bending punch. A manufacturing method of a high-strength press part, wherein the plate end portion is coined by being moved in a direction of approaching. In the manufacturing method of the high intensity | strength press part described in Claim 1 or Claim 2,
The bending die includes a nest having a concave shaped portion that abuts on the convex portion in the substantially U-shaped cross section,
After the bending process, the bending die and the bending blade are moved by a predetermined length in a direction away from the bending punch, and then only the insert is moved in a direction close to the bending punch, and then the bending die. And a method of manufacturing a high-strength press part, wherein the edge of the plate is coined by moving the bending blade again in the direction approaching the bending punch. Bending dies and bending blades having a concave-shaped forming part as a whole, sandwiching a steel sheet punched into a developed shape and bending it into a substantially U-shaped cross section, a bending punch having a convex-shaped forming part, A press die for use in a method of manufacturing a high-strength press part comprising a coining blade having a concave groove for coining by inserting a plate end of a side wall flange in a letter-shaped cross section,
The press die, wherein the bending blade can be brought into contact with the plate end during the bending process, and the bending blade can be moved away from the plate end before the coining. In the press die used for the manufacturing method of the high intensity | strength press part described in Claim 5,
The press die, wherein the coining blade moves in a direction close to the bending punch after the bending process so that the plate end portion can be inserted into the concave groove. In the press die used for the manufacturing method of the high intensity | strength press part described in Claim 5 or Claim 6,
The press die, wherein the bending die is provided at the lower end of the opening of the bending die so as to be movable in a direction crossing the pressing direction. In the press die used for the manufacturing method of the high intensity | strength press part described in Claim 5 or Claim 6,
The bending die includes a nest having a concave shaped portion that abuts on a convex portion in the substantially U-shaped cross section, and only the nest is movable in a direction close to the bending punch. A featured press mold.

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