JP2013202619A - Hot press molding apparatus and hot press molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot press molding apparatus which allows molding in a short cycle time without enlarging whole equipment.SOLUTION: In a hot press molding apparatus 10, a blank 40 is arranged between a fixed die 11 as a lower die and a movable die 12 as an upper die so as to be heated so that its temperature becomes higher than that in the fixed die and the movable die, and the movable die 12 is lowered for clamping, so that a press-molded product is produced. In the fixed die 11, a recess 22 is formed, and in the movable die 12, a projection 32 entering the recess 22 is formed. During press-molding, an end corner part of the projection 32 abuts on a part where the blank 40 bends first. The projection 32 has a body molding part 33 and a movable body 34 provided separately from the body molding part 33 so as to be movable in a clamping direction. The movable body 34 moves in a clamping direction so as to project to the recess 22 side from the body molding part 33, and the end corner part serves as the movable body 34.

Description

  The present invention relates to a hot press molding apparatus and a hot press molding method.

  A hot press that heats a blank made of hardenable steel, and puts the heated blank into a cooled mold and clamps it to form a desired shape while quenching and quenching. Molding is known. By using a galvanized steel material as a blank, it is possible to manufacture a hot press molded product having excellent corrosion resistance.

  However, if the galvanized steel material is clamped in a state where it is heated to about 900 ° C., there is a problem in that intergranular cracking occurs due to the molten zinc entering the crystal grain boundaries. In order to solve this problem, a quenching facility for rapidly cooling to 800 ° C. or less is provided between a heating facility for heating a galvanized steel material to about 900 ° C. and a hot press facility for quenching and clamping while quenching. A technique has been proposed (see, for example, Patent Document 1). Due to the presence of the rapid cooling facility, it is possible to eliminate molten zinc, and it is possible to suppress intergranular cracking during mold clamping.

JP 2007-182608 A

  However, in the above-described conventional technique, it is necessary to provide a quenching facility between the heating facility and the hot press facility, which causes a problem that the cycle time becomes long and the production efficiency decreases, and the size of the entire facility is increased. There is a problem.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a hot press molding apparatus and a hot press molding method capable of molding in a short cycle time without causing an increase in the size of the entire facility. .

In order to achieve the above object, the invention of claim 1 includes an upper mold and a lower mold that are relatively close to and away from each other, a concave molding portion formed on one of the upper mold and the lower mold, and an upper mold or a lower mold. A convex shaped part that is formed on the other side of the concave shaped part and enters the concave shaped part,
A hot press in which a heated blank is placed between the upper mold and the lower mold, which is lower in temperature than the blank, and is clamped by the upper mold and the lower mold, thereby performing press molding and quenching. A molding device,
During the press molding, the blank is configured to be bent first at the tip corner of the convex molding part,
The convex molding part includes a main body molding part and a movable molding part that is provided separately from the main body molding part and is movable in the clamping direction.
The movable molding portion is disposed at a position protruding from the main body molding portion toward the concave molding portion when the upper die and the lower die are separated from each other, and in the clamped state, the main body molding portion. Are arranged in an integrated position,
The tip corner is the movable molding part.

  According to this configuration, by placing the blank in the mold and performing press molding, the blank is deformed by being sandwiched between the convex molding portion and the concave molding portion, and the blank is deformed into the convex and concave molding portions. A combined bent portion is formed. Here, when performing the above press molding, the latter of the main body molding portion and the movable molding portion constituting the convex molding portion is brought into contact with the first bending portion in the blank first. Is possible. Thus, the temperature of the contact portion can be lowered before mold clamping by previously contacting the movable forming portion which is the tip corner portion of the convex forming portion with respect to the first bent portion.

  For example, by using a galvanized steel sheet or the like as a blank, it is possible to produce a press-formed product having excellent corrosion resistance. However, when the plated steel material is clamped in an extremely heated state (for example, about 900 ° C.). When the steel sheet bends at a high temperature, the molten plating (zinc particles in the case of a galvanized steel sheet) enters the crystal grain boundaries of the steel sheet and may cause grain boundary cracking. Certainly, it is possible to avoid such inconvenience by performing press molding after waiting until the entire blank is cooled to some extent, but such countermeasures hinder cycle time reduction and reduce production efficiency. Can be reduced. In addition, in consideration of manufacturing efficiency, provision of a quenching facility can contribute to shortening the cycle time, but this may cause a problem that the size of the entire facility is increased.

  In this regard, in the first aspect of the invention, the movable molded portion is brought into contact with the blank in advance of the main body molded portion at the first bent portion where the grain boundary crack is likely to occur. It becomes possible to cool partially. That is, the partial cooling period can be incorporated in the transition period when the mold is closed. Thereby, it is possible to avoid the occurrence of intergranular cracks in the blank without providing a separate quenching facility, and it is possible to suppress an increase in the size of the entire facility and the cycle time for manufacturing.

  According to a second aspect of the present invention, in the first aspect of the invention, the convex molding portion is provided in the upper mold so as to protrude downward, and in a state where the upper mold and the lower mold are separated from each other, The movable molding part is arranged at the protruding position by its own weight.

  According to this configuration, in a state where the upper mold and the lower mold are opened, the movable molding portion stands by with its own weight protruding downward. Thus, by providing the movable molding part on the upper mold and moving it using the weight of the movable molding part itself, an actuator for driving the movable molding part is not required, and the effect of claim 1 can be achieved with a simple configuration. It can be demonstrated.

  A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the movable molding portion includes a flow path for circulating a cooling medium.

  According to this configuration, by allowing the cooling medium to flow through the flow path of the movable molding portion, when the movable molding portion abuts against the blank, it is possible to efficiently cool the contact portion and its peripheral portion. Become. Accordingly, it is possible to shorten the period required for cooling the first bent portion in the blank and contribute to shortening the cycle time.

Invention of Claim 4 is the hot press molding method using the hot press molding apparatus of any one of Claim 1 thru | or 3, Comprising:
A heated blank is placed between the upper mold and the lower mold at a temperature lower than that of the blank,
In the arrangement state, the movable molding part is brought into contact with the blank before the main body molding part,
From the abutting state, the blank molding is performed by press molding and quenching in a state where the main body molding portion and the movable molding portion are integrated by clamping the upper die and the lower die. .

  According to this molding method, using the hot press molding apparatus according to any one of claims 1 to 3, it is possible to avoid occurrence of intergranular cracks in the blank without providing a quenching facility separately, It is possible to suppress an increase in the overall equipment size and the cycle time for manufacturing. As a result, the molding cost can be reduced.

  According to the present invention, hot press molding can be performed in a short cycle time without increasing the size of the entire facility.

Schematic which shows the mode of the hot press molding in 1st Embodiment. Schematic which shows the mode of the hot press molding in 1st Embodiment. Schematic which shows the specific example of the main body shaping | molding part and movable body in 1st Embodiment. Schematic which shows 2nd Embodiment.

<First Embodiment>
The main configuration of the press molding die apparatus and the flow of hot press molding in the first embodiment will be described below with reference to FIGS. 1 and 2.

  In the present embodiment, the mold apparatus is embodied as a hot press molding apparatus 10 having a fixed mold 11 and a movable mold 12, and the hot press molding apparatus 10 manufactures a press-processed product having corrosion resistance. Assumed.

  1A is a schematic view showing a mold open state in which the fixed mold 11 and the movable mold 12 are separated from each other, and FIG. 1B is a mold open state in which the fixed mold 11 and the movable mold 12 are separated. FIG. 1C is a schematic view showing a state in which the blank 40 is installed. FIG. 1C is a schematic view showing a state in which the movable die 12 is lowered and the movable body 34 constituting a part thereof is in contact with the blank 40. FIG. (D) is a schematic diagram showing a state in which the blank 40 is bent due to continued lowering of the movable mold 12, and FIG. 2 (e) is a schematic diagram showing a state where the die is closed and a press-work product is completed. FIG. 2 (f) is a schematic view showing a state in which the press-opened product is taken out after returning to the mold open state.

  As shown in FIG. 1A, a hot press molding apparatus 10 includes a fixed mold 11 as a lower mold fixed to a bolster (pedestal), and a fixed mold 11 positioned above the fixed mold 11. The movable mold 12 is provided so as to be movable (movable up and down) on the side closer to 11 and on the side farther away. When these two molds 11 and 12 are switched from the mold open state to the mold closed state, that is, the mold is clamped, a press-work product is manufactured.

  The fixed mold 11 is formed with a recess 22 that is recessed downward from the upper surface 21 thereof. The recess 22 has a groove shape extending in a direction orthogonal to the direction of combination of the molds (specifically, a direction orthogonal to the cross section of FIG. 1A), and the wall 24 that rises upward from the bottom 23. Corner portions 25 and 26 are formed at the boundary portion of the wall portion 24 and the boundary portion (upward opening portion) of the wall portion 24 and the upper surface 21.

  A convex portion 32 having a shape corresponding to the concave portion 22 is formed on the movable mold 12. The convex portion 32 protrudes downward from the lower surface 31 of the movable mold 12 and is accommodated in the concave portion 22 when the hot press molding apparatus 10 is in the mold closed state.

  Both ends of the convex part 32, specifically, the part facing the corner part 25 of the fixed mold 11 in the mold closed state, is formed separately from the main body molding part 33 constituting the base part of the convex part 32. It is comprised by the movable body 34 as a movable shaping | molding part.

  The movable body 34 is assembled to the main body molding portion 33 so as to be slidable (can be raised and lowered) in the same direction as the moving direction of the movable mold 12. It descends to its lower limit by its own weight and waits at that lower limit. On the other hand, when an upward external force is applied to the movable body 34, the movable body 34 moves upward to form a convex portion 32 integrated with the main body molding portion 33. The movable body 34 is formed of the same material as that of the main body molding portion 33 and is devised so that a step or the like does not occur at a boundary portion with the main body molding portion 33 in the process of heating / cooling.

  In the present embodiment, in order to support the lowering of the movable body 34 due to its own weight, the spring member 35 as a biasing means that biases the movable body 34 downward is formed between the main body molding portion 33 and the movable body 34. Is intervening.

  In the present embodiment, a plurality of flow paths 28 and 38 through which the cooling medium flows are formed in the molds 11 and 12 in order to perform quenching by hot pressing. These flow paths 28 and 38 are connected to a cooling device (not shown) provided in the hot press molding device 10, and the cooling medium cooled by the cooling device is circulated in the molds 11 and 12. Thus, it is possible to cool the peripheral portions of the flow paths 28 and 38. Since a plurality of the flow paths 28 and 38 are disposed along the opposing surfaces (press surfaces) provided in the molds 11 and 12 in the molds 11 and 12, the blank 40 is provided. Suitable for rapid cooling. Here, the flow path 39 connected to the cooling device is also formed in the movable body 34 provided in the movable mold 12, and the temperature of the movable body 34 is sufficiently lowered.

  Next, the flow of hot press molding will be described. When performing hot press molding, a hot press molding apparatus in the order of FIG. 1 (a) → FIG. 1 (b) → FIG. 1 (c) → FIG. 2 (d) → FIG. 2 (e) → FIG. 10 will operate. In FIG. 1B and FIG. 1C, the blank 40 is depicted as being in surface contact with the upper surface 21 of the fixed mold 11, but actually the blank 40 is the upper surface of the fixed mold 11. It is supported by a plurality of protrusions (not shown) provided at 21 in point contact. That is, the protrusion (not shown) includes a spring member, and is a movable type configured to be able to protrude and retract with respect to the upper surface 21 of the fixed mold 11.

  First, as shown in FIG. 1A, the movable mold 12 is moved upward to switch to the mold open state. In this state, the movable body 34 is at a position spaced downward from the main body molding portion 33. In the mold open state, the blank 40 is disposed on the upper surface 21 of the fixed mold 11 as shown in FIG. Here, in the present embodiment, a galvanized steel sheet is used as the blank 40, and the blank 40 is heated to about 900 ° C. by a separately provided heating facility, and the upper surface 21 of the fixed mold 11 in the heated state. Is to be arranged. At this time, the blank 40 is about 800 ° C. by natural cooling.

  After the arrangement of the blank 40 is completed, the movable mold 12 starts to descend as shown in FIG. When the movable mold 12 is lowered to a predetermined position, the tip portion of the movable body 34 constituting the convex portion 32 first comes into contact with the blank 40. Thereby, the part which contact | abutted with the movable body 34 in the blank 40 will be cooled ahead of time before mold clamping is performed. Even if the movable mold 12 is further lowered, the cooling at the contact portion between the movable body 34 and the blank 40 is continued until the main body molding portion 33 and the movable body 34 are integrated. During operation, it is ensured as a rapid cooling period of the contact portion. By securing this period, the temperature of the portion in contact with the movable body 34 is 700 ° C. or lower at which no grain boundary cracking occurs, and 650 ° C. or higher at which quenching has not yet occurred. Further, since the spring member 35 is biased downward, it has a function of reliably pressing the movable body 34 against the blank 40.

  In FIGS. 1 and 2, the temperature decrease of the blank 40 due to the preceding contact with the movable body 34 is schematically represented by the density of dot hatching. Specifically, the portion where the dot hatching density is low indicates a state where the temperature is lower than that of the high portion.

  When the movable body 34 reaches the upper limit position by continuing the lowering of the movable mold 12, the outer surfaces of the main body molding portion 33 and the movable body 34 are in an integrated state in which a continuous surface is formed. Thereafter, the descent of the movable mold 12 is further continued, so that the blank 40, specifically, the portion where the movable body 34 of the convex portion 32 is in contact starts to bend (see FIG. 2D).

  As shown in FIG. 2 (d) → FIG. 2 (e), after the movable mold 12 is lowered to the lower limit position and the mold clamping is completed, the blank 40 is bent in accordance with the molds 11 and 12. A part is formed. By maintaining this state for a short period of time, the entire blank 40 is rapidly cooled to 650 ° C. or lower and quenched.

  Thereafter, as shown in FIG. 2 (f), the movable mold 12 is raised, and the blank 40 that has become a press-processed product is removed from the hot press molding apparatus 10. At this time, as the movable mold 12 is raised, the movable body 34 is lowered again to the lower position by its own weight and the urging force of the spring member 35 and waits at the lower position.

  Here, based on FIG. 3, the specific structure for implement | achieving raising / lowering of the movable body 34 is illustrated. FIG. 3 is a schematic view showing a combined structure of the main body molding portion 33 and the movable body 34 in the convex portion 32, and FIG. 3 (a) shows a state where the movable body 34 stands by at the lower limit position, and FIG. ) Shows a state in which the movable body 34 is pushed up to the upper limit position.

  An accommodation recess 51 for accommodating the movable body 34 is formed at the tip corner of the main body molding portion 33. A return portion 53 is formed on a side surface 52 of the housing recess 51 facing the movable body 34 so as to protrude from the lower end position toward the movable body 34. The return portion 53 includes an extending portion 53a that extends toward the movable body 34 and a standing portion 53b that rises upward from the extending portion 53a.

  The standing portion 53b is formed to be parallel to the side surface 52, and is opposed to the side surface 52 with a predetermined interval. An arm portion 61 is formed in a portion of the movable body 34 facing the side surface 52, and this arm portion 61 is inserted into the return portion 53 (a space sandwiched between the upright portion 53b and the side surface 52). Yes. Thus, the movable body 34 is restricted from falling off, and the sliding direction is defined to be the same direction (vertical direction) as the moving direction of the movable mold 12.

  The length dimension (vertical dimension) of the arm part 61 is set longer than the length dimension (vertical dimension) of the standing part 53b. As shown in FIG. 3 (a), the position where the tip of the arm portion 61 abuts on the extending portion 53a is the lower limit position of the movable body 34. As shown in FIG. 3 (b), the movable body A position where the upper surface of 34 abuts on the ceiling 54 of the housing recess 51 from below is the upper limit position of the movable body 34.

  As shown in FIG. 3B, when the movable body 34 is housed in the housing recess 51, the upper surface and the side surface of the movable body 34 are in contact with the ceiling portion 54 and the side surface 52 of the housing recess 51. As a result, the reaction force generated when the blank 40 is pushed by the corner portion 62 or the like of the movable body 34 is transmitted from the movable body 34 to the main body molding portion 33, and the load concentrates on the attachment portion or the like of the movable body 34. Is avoiding.

  In particular, in the accommodated state, the tip portion of the arm portion 61 and the standing portion 53b are in a wrapped state, and deformation of the arm portion 61 and the standing portion 53b is also suppressed. In addition, when forming the state in which the upper surface and the side surface of the movable body 34 are in contact with the housing recess 51, the spring member 35 can be housed in the compressed state of the spring member 35 so that the spring member 35 does not get in the way. A seat 58 is formed in the main body molding portion 33.

  As described above, according to the first embodiment described in detail, the following excellent effects can be expected.

  When the blank 40 is placed in the molds 11 and 12 and hot press molding is performed, the blank 40 is deformed by being sandwiched between the convex portion 32 and the concave portion 22, and is aligned with the convex portion 32 and the concave portion 22. A bent portion will be formed. Here, when the hot press molding is performed, the latter of the main body molding portion 33 and the movable body 34 constituting the convex portion 32 is preceded by a portion of the blank 40 that can be bent first in the press molding process. Can be brought into contact with each other. As described above, by previously bringing the movable body 34 into contact with a portion that can be bent first, the temperature of the portion can be lowered before clamping.

  As already described, in the present embodiment, it is assumed that a press-formed product having excellent corrosion resistance is manufactured by using a galvanized steel sheet as the blank 40. When the galvanized steel sheet is heated to about 900 ° C. and then clamped in a state where the temperature is not lower than 700 ° C., the molten zinc particles enter the crystal grain boundaries of the steel sheet when the steel sheet bends at a high temperature. Intergranular cracking can occur.

  Although it is possible to avoid the molten zinc particles from entering the crystal grain boundaries of the steel sheet by performing the press forming after waiting until the entire blank 40 is cooled to some extent, such measures can reduce the cycle time. This may hinder manufacturing efficiency. In addition, the provision of a rapid cooling facility can contribute to shortening the cycle time, but this may cause another problem of increasing the size of the entire facility.

  In this respect, in the present embodiment, the movable body 34 is brought into contact with the blank 40 prior to the main body molding portion 33 for the bent portion where the grain boundary crack is likely to occur, and the contact portion and the contact portion. The area around is partially cooled. That is, the partial cooling period can be incorporated in the transition period when the mold is closed. Accordingly, it is possible to prevent the occurrence of intergranular cracking in the blank 40 and to suppress an increase in the size of the entire equipment and the cycle time required for manufacturing due to the crack.

  Further, when the hot press molding apparatus 10 is in the mold open state, the movable body 34 stands by at its lower limit position within its own movement range due to its own weight. Moreover, the spring member 35 is only provided as the support. As a result, an actuator for lowering the movable body 34 is not required, and the hot press molding apparatus 10 can be suitably prevented from becoming complicated.

  The movable body 34 is formed with a flow path 28 through which the cooling medium flows. According to such a configuration, when the movable body 34 abuts on the blank 40, it is possible to rapidly cool the abutting portion and its peripheral portion efficiently. Thereby, it is possible to shorten the period required for cooling the portion of the blank 40 that bends first, thereby contributing to the reduction of the cycle time.

  A large reaction force is applied to the corner 62 when the mold 34 is clamped. Since the movable body 34 is in contact with the main body molding portion 33 from below and from the side at the time of the pressing, the reaction force is propagated to the main body molding portion 33 and dispersed, whereby the main body molding portion 33 and The movable body 34 is not deformed or damaged.

<Second Embodiment>
In the first embodiment, a guide function for raising and lowering the movable body 34 is given to the return portion 53 provided in the main body molding portion 33 and the arm portion 61 provided in the movable body 34. In this embodiment, the configuration for providing the guide function is different from that of the first embodiment. Hereinafter, a configuration for providing the guide function of the movable body 34A will be described with reference to FIG. FIG. 4 is a schematic view showing a combined structure of the main body molding portion 33A and the movable body 34A. The various configurations other than the guide portion are basically the same as those in the first embodiment, and thus the description thereof is omitted.

  A rail member 55A is provided in the housing recess 51A formed in the main body molding portion 33A. The rail member 55A is made of the same material as that of the main body molding portion 33, and is fixed to the side surface 52A of the housing recess 51A.

  On the other hand, a housing groove 65A capable of housing the rail member 55A is formed in a portion of the movable body 34 facing the side surface 52A. The housing groove 65A is open to the side surface 52A and upward, while the lower side is closed. Further, since the rail member 55A is accommodated in the accommodation groove 65A, the contact between the rail member 55A and the blank 40 is avoided.

  A groove 56A extending in the same direction as the moving direction (vertical direction) of the movable mold 12A is formed in the rail member 55A, and a slider 66A that engages with the groove 56A is fixed to the accommodation groove 65A of the movable body 34A. ing. In other words, the moving direction of the slider 66A is regulated by the groove portion 56A so as to be the vertical direction. The slider 66A is also made of the same material as that of the rail member 55A, and the engagement is prevented from becoming stronger or weaker due to contraction / expansion due to heat.

  A stopper 57A that prevents the slider 66A from further descending is formed at the lower end of the rail member 55A. As shown in FIG. 4A, the position where the slider 66A contacts the stopper 57A is the movable body. It is the lower limit position of 34A.

  On the other hand, the upper end of the rail member 55A does not have a stopper corresponding to the upward movement of the slider 66A, and the upper surface of the movable body 34A is the same as that of the housing recess 51A as in the first embodiment. By abutting on the ceiling portion 54A from below, further upward movement is prevented (see FIG. 4B).

  In the present embodiment, it is possible to more efficiently use the weight of the movable body 34A by adopting a configuration dedicated to the movement of the movable body 34A such as the rail member 55A and the slider 66A. Thus, since the smooth movement of the movable body 34A is ensured, the spring member 35 having the support function in the first embodiment is omitted.

<Other embodiments>
In addition to the embodiments described above, for example, the following may be implemented. Each of the following embodiments may be applied individually to the configuration in each of the above embodiments, or may be applied in combination with each other.

  (1) In each of the above embodiments, the “upper mold” is the movable mold 12 and the “lower mold” is the fixed mold 11, but it is arbitrary which one is the fixed mold / movable mold. is there. That is, the “upper mold” may be a fixed mold and the “lower mold” may be a movable mold.

  (2) In the above embodiment, the movable mold 12 as the “upper mold” is provided with the convex part 32 as the “convex molded part”, and the fixed mold 11 as the “lower mold” is used as the “concave molded part”. The concave portion 22 is provided, but the relationship between the convex portion and the concave portion may be reversed. That is, it is possible to provide a configuration in which a convex portion is provided on the lower mold, and the movable body 34 constituting the convex portion is urged upward (upper limit position) by a spring member or the like as urging means.

  (3) In each of the above embodiments, in order to return the movable body 34 as the “movable molding portion” from the upper limit position to the lower limit position, the weight of the movable body 34 is mainly used. If it is possible to return, it is not always necessary to use its own weight. For example, magnetic force may be used, or a driving device such as an actuator for moving the movable body 34 may be used.

  DESCRIPTION OF SYMBOLS 10 ... Hot press molding apparatus, 11 ... Fixed mold as lower mold, 12 ... Movable mold as upper mold, 22 ... Concave part as concave molding part, 32 ... Convex part as convex molding part, 33 ... Main body Molding part, 34 ... movable body as movable molding part, 38 ... flow path, 40 ... blank.

Claims (4)

An upper mold and a lower mold that are relatively close to and away from each other, a concave molding portion formed on one of the upper mold and the lower mold, and a convex shape that is formed on the other of the upper mold and the lower mold and enters the concave molding section. A molding part,
A hot press in which a heated blank is placed between the upper mold and the lower mold, which is lower in temperature than the blank, and is clamped between the upper mold and the lower mold, thereby performing press molding and quenching. A molding device,
During the press molding, the blank is configured to be bent first at the tip corner of the convex molding part,
The convex molding part includes a main body molding part and a movable molding part that is provided separately from the main body molding part and is movable in the clamping direction.
The movable molding portion is disposed at a position protruding from the main body molding portion toward the concave molding portion when the upper die and the lower die are separated from each other, and in the clamped state, the main body molding portion. Are arranged in an integrated position,
The hot press molding apparatus characterized in that the tip corner is the movable molding part.   The convex molding part is provided in the upper mold so as to protrude downward, and when the upper mold and the lower mold are separated from each other, the movable molding part is arranged at the protruding position by its own weight. The hot press molding apparatus according to claim 1.   The hot press molding apparatus according to claim 1, wherein the movable molding unit includes a flow path for circulating a cooling medium. A hot press molding method using the hot press molding apparatus according to any one of claims 1 to 3,
A heated blank is placed between the upper mold and the lower mold at a temperature lower than that of the blank,
In the arrangement state, the movable molding part is brought into contact with the blank before the main body molding part,
From the abutting state, the blank molding is performed by press molding and quenching in a state where the main body molding portion and the movable molding portion are integrated by clamping the upper die and the lower die. Hot press molding method.

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