JP2010179317A - Hot press forming method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot press forming method and apparatus by which only region, where high strengthening is required, can be quenched in formed products having various shapes. <P>SOLUTION: The hot press forming apparatus 10, with which a workpiece W is quenched by cooling while press-forming the same after performing the heating control of the workpiece W in accordance with the required strength in respective regions of the formed parts, is provided with: electrodes 31 for heating the workpiece W to quenchable temperature or above; air blow nozzles 32 for jetting the air to optional places of the workpiece W during heating with the electrodes 31; and partition plates 33 for limiting the jetting region of the air to be jetted to the workpiece W from the air blow nozzles 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hot press molding method and apparatus for performing quenching while press molding after heating a molding material.

  In recent years, in the automobile field, for the purpose of reducing carbon dioxide emissions through improving fuel efficiency and improving safety performance, the strength of automobile structural members has been increased (high tenacity). The use ratio of high strength steel plates is increasing for steel plates that are representative materials. However, as the strength of the member (material) increases, the formability such as elongation of the material deteriorates, so cracks and wrinkles occur during molding, dimensional accuracy defects occur, or post-cut processing There were problems such as becoming difficult. Further, with the increase in strength, the welding quality at the time of joining the members (for example, a decrease in plate alignment accuracy, poor contact with the electrodes, a decrease in the life of the electrodes, etc.) and productivity are also deteriorated. In addition, since the material strength variation increases as the strength of the material increases, it is difficult to stabilize the pressability and weldability.

  As a method for solving such a problem, a process called a die quench method can be cited. In this die quench method, a die is heated to a predetermined temperature (for example, a temperature at which an austenite phase is formed) to lower the strength (that is, to facilitate molding), and then is a lower temperature (for example, room temperature) than the material. By molding with, a quenching heat treatment (quenching) utilizing the temperature difference between the two is performed at the same time as imparting the shape to ensure the strength after molding. By this method, the problem of cracks and wrinkles during molding and the problem of poor dimensional accuracy are solved. However, this method increases the strength of the entire material, and cannot solve the problems of post-drawing workability and weldability.

  For this reason, various techniques for partially quenching the material during press molding have been proposed. In these technologies, a predetermined temperature distribution is formed on the material by heating means and cooling means so that the strength of each part of the molded product can be arbitrarily set during hot pressing, and quenching is performed while press forming. Like to do. For example, in the technique described in Patent Document 1, a predetermined temperature distribution is formed on the material by masking the material or removing heat from contact with the conveying device. Moreover, in the technique described in Patent Document 2, a predetermined temperature distribution is formed on the material by disposing a heating electrode in a portion requiring quenching. In this manner, partial hardening can be performed by press forming after a predetermined temperature distribution is formed on the material.

JP 2006-212690 A JP 2008-87001 A

  However, as in the technique described in Patent Document 1 described above, in contact heat removal with a masking or conveying device, it is necessary to create a dedicated product for each molded product or for each cooling part. There was a problem that it was difficult to deal with. Further, in a complicated shape such as having a step, there is a problem that a predetermined temperature distribution cannot be formed on the material because the masking and the conveying device cannot be brought into contact with each other.

  Further, in the technique described in Patent Document 2 described above, since the heating region expands outside the region sandwiched between the electrodes, it is difficult to form a predetermined temperature distribution on the material, and high strength is achieved. In practice, it is very difficult to quench only the necessary parts. And this problem becomes remarkable with a complicated shape.

  Accordingly, the present invention has been made to solve the above-described problems, and a hot press molding method capable of quenching only a portion where high strength is required for molded products having various shapes. And providing an apparatus.

  The invention made in order to solve the above problems is a hot press molding method in which the molding material is subjected to heating control according to the required strength of each part of the molded product, and then quenched by cooling while being press molded. Of the molding material so that the heating temperature is locally lower than the quenching temperature by injecting the coolant to any part of the molding material being heated by the heating step. And a heating control step for performing heating control.

  In this hot press molding method, in the heating step, the molding material is heated to a temperature at which quenching is possible. And in a heating control process, a refrigerant | coolant is injected to the arbitrary locations of the shaping | molding raw material currently heated by a heating process. Thereby, the state where the temperature of the portion where the refrigerant is injected is kept lower than the quenchable temperature. As a result, it is possible to heat only the portion of the molding material that requires strength to a temperature that can be quenched. That is, a predetermined temperature distribution can be appropriately formed on the molding material. The molding material thus controlled by heating is press-molded with a low-temperature (room temperature) mold. At this time, a portion of the molding material that has been heated to a temperature higher than or equal to the quenching temperature is rapidly cooled, and a molded product in which only this portion is quenched is completed.

  In this hot press molding method, the non-quenched region can be easily and accurately formed simply by adjusting the injection position of the refrigerant. In addition, this method uses a non-contact method instead of removing heat by bringing a masking or conveying device into contact, so even if the shape is complicated, such as having a step, a predetermined temperature distribution can be formed on the molding material. it can. For these reasons, according to this hot press molding method, it is possible to cope with molded products of various shapes.

  As described above, according to this hot press molding method, a desired temperature distribution can be flexibly formed in the molding material in accordance with the shape of the molded product. Quenching can be performed only on the necessary parts.

In the hot press molding method according to the present invention, in the heating control step, the heating temperature of the molding material may be made lower than the local quenching temperature by limiting the injection region of the refrigerant.
Alternatively, in the heating control step, the heating temperature of the molding material may be locally lower than the quenchable temperature by inclining the coolant injection angle toward the outer side of the quenching portion with respect to the molding material. .

  In this way, by limiting the refrigerant injection region or inclining the refrigerant injection angle, the cooling region (non-quenched region) can be formed with high accuracy by refrigerant injection. That is, a desired temperature distribution can be accurately formed on the molding material in accordance with the required strength of the molded product.

  The invention made in order to solve the above-mentioned problem is a molding material in a hot press molding apparatus in which the molding material is subjected to heating control according to the required strength of each part of the molded product and then quenched by cooling while being press-molded. A heating means for heating the material to a temperature at which quenching can be performed or higher, a refrigerant injection means for injecting a refrigerant to an arbitrary portion of the molding material being heated by the heating means, and a refrigerant injected from the refrigerant injection means to the molding material Limiting means for limiting the injection region.

  In this hot press molding apparatus, the molding material is heated to a temperature higher than the quenching capability by the heating means. During the heating of the molding material, the refrigerant is injected into the molding material by the refrigerant injection means. At this time, the injection region of the refrigerant injected from the refrigerant injection unit is limited by the limiting unit. Thereby, a refrigerant | coolant can be accurately injected with respect to the arbitrary locations of a shaping | molding raw material. And the state where the temperature of the part into which the refrigerant | coolant was injected is lower than the quenching possible temperature is maintained. As a result, it is possible to heat only the portion of the molding material that requires strength to a temperature that can be quenched. That is, a predetermined temperature distribution can be appropriately formed on the molding material. Thereafter, the molding material heated in this manner is press-molded with a mold having a temperature lower than that of the material, thereby completing a molded product.

  In addition, this hot press molding apparatus is a non-contact method in which the temperature of the molding material is controlled by injecting a refrigerant instead of removing heat by contacting a masking or conveying device. Even with the shape, a predetermined temperature distribution can be formed on the molding material. Therefore, according to this hot press molding apparatus, it is possible to press-mold the molded products having various shapes while quenching only the portions that require high strength.

  In the hot press molding apparatus according to the present invention, the restricting means includes a partition plate that partitions the refrigerant injection region and the refrigerant non-injection region in the molding material, or refrigerant suction that sucks the refrigerant flowing in the refrigerant non-injection region in the molding material. Means may be used.

  By adopting such a configuration, it is possible to realize a limiting unit that limits the injection region of the refrigerant injected from the refrigerant injection unit with a simple configuration. That is, since the injection region of the refrigerant can be accurately set with a very simple configuration, only the portion of the molding material that requires strength can be heated to a temperature higher than the quenching temperature.

  And in the hot press molding apparatus which concerns on this invention, it is desirable that the said limitation means is integrally provided in the said refrigerant | coolant injection means.

  As described above, since the limiting unit is integrated with the refrigerant injection unit, it is not necessary to separately arrange the refrigerant injection unit and the limiting unit, so that it takes time to form a predetermined temperature distribution on the molding material. It can be shortened. As a result, productivity can be improved.

  Further, in the hot press molding apparatus according to the present invention, the limiting means controls the injection direction of the refrigerant injection means so as to incline the injection angle of the refrigerant with respect to the molding material toward the outer side of the quenched portion of the molding material. Control means may be used.

  In this way, by controlling the injection direction of the refrigerant injection means by the control means so that the injection angle of the refrigerant with respect to the molding material is inclined in the outer direction of the quenching portion of the molding material, any part (non- The refrigerant can be injected only into the quenching region). Therefore, only a portion (quenching region) where strength is required in the molding material can be heated to a temperature that can be quenched or higher.

  According to the hot press molding method and the molding apparatus according to the present invention, as described above, the molded products having various shapes including the complex shape are quenched only to the portions that require high strength during press molding. be able to.

It is a front view which shows schematic structure of the shaping | molding apparatus which concerns on embodiment. It is an enlarged view near a work heating mechanism part. It is a top view which shows schematic structure of a workpiece | work heating part. It is a figure which shows schematic structure of the air blow nozzle with which a workpiece | work heating part is equipped. It is a figure which shows schematic structure of an air blow nozzle provided with a suction nozzle. It is a figure which shows schematic structure of an air blow nozzle provided with a nozzle injection angle variable unit. It is a figure which shows a mode that predetermined | prescribed temperature distribution is formed (heating control) on a workpiece | work. It is a perspective view which shows the press-molded molded product. It is sectional drawing which shows the press-molded molded article. It is a figure which shows the hardness in each part of the press-molded molded article. It is a perspective view which shows the cross-sectional hat-shaped molded product curved in the longitudinal direction. It is a figure which shows the arrangement position of each air blow nozzle at the time of shape | molding the molded article shown in FIG. It is a perspective view which shows the cross-sectional hat-shaped molded product curved in the longitudinal direction. It is a figure which shows the arrangement position of each air blow nozzle at the time of shape | molding the molded article shown in FIG. It is a figure which shows schematic structure of the modification of a shaping | molding apparatus. It is a figure which shows the arrangement position of the air blow nozzle in the case of performing post-cutting.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. Then, the shaping | molding apparatus which concerns on this Embodiment is demonstrated, referring FIGS. 1-4. Drawing 1 is a front view showing a schematic structure of a forming device concerning an embodiment. FIG. 2 is an enlarged view of the vicinity of the workpiece heating mechanism. FIG. 3 is a plan view showing a schematic configuration of the workpiece heating unit. FIG. 4 is a diagram illustrating a schematic configuration of an air blow nozzle provided in the workpiece heating unit.

  As shown in FIG. 1, in the molding apparatus 10 according to the present embodiment, a press working unit 11 that press-molds a work W, and a desired temperature distribution is formed on the work W before press molding by the press working unit 11. And a work heating unit 30 for the purpose. The work W is a flat steel plate.

  The press working part 11 includes an upper mold 12 provided so as to be movable up and down, and a lower mold 13 fixedly arranged so as to face the upper mold 12. The upper mold 12 is provided with a protruding portion 12a protruding downward, and the lower mold 13 is formed with a concave portion 13a formed in a concave shape corresponding to the protruding portion 12a. Then, by combining the protrusion 12a of the upper mold 12 and the recess 13a of the lower mold 13, the workpiece W is formed into a cross-sectional hat shape (a shape in which flanges projecting outward at both ends of the U-shaped cross section are integrally formed). It is configured as follows.

  In this press working part 11, the upper die 12 is attached to the upper die plate 16 via a spring 14 and a spring guide 15, and this upper die plate 16 is attached to the upper die holder 17. On the other hand, the lower mold 13 is attached to the lower mold holder 18. An outer guide 19 fixed to the lower mold holder 18 is incorporated in an outer guide bush 20 provided in the upper mold holder 17. An inner guide 21 fixed to the upper mold plate 16 is incorporated in an inner guide bush 22 provided in the upper mold 12 and an inner guide bush 23 provided in the lower mold 13. Accordingly, the positioning accuracy of the upper mold 12 and the lower mold 13 is ensured in the press working portion 11.

  A drive mechanism (not shown) is connected to the upper mold holder 17 so as to move the upper mold holder 17 in the vertical direction. Thus, since the upper mold 12 is attached to the upper mold holder 17 via the spring guide 15 and the upper mold plate 16, the upper mold 12 is moved when the upper mold holder 17 is moved in the vertical direction by the drive mechanism. It is designed to move up and down. As the upper mold 12 moves up and down, the upper mold 12 and the lower mold 13 come into contact with and separate from each other, and the workpiece W is pressed.

The workpiece heating unit 30 includes electrodes 31 that are disposed at both ends of the workpiece W in the longitudinal direction and electrically heat the workpiece W, and an air blow nozzle 32 that locally cools the workpiece W.
As shown in FIGS. 2 and 3, the electrodes 31 are arranged at both ends of the workpiece W so as to be separated from each other, and are connected to a power source (not shown). The electrodes 31 are brought into contact with the workpiece 1 and energized, whereby the workpiece W can be heated to a temperature higher than the quenching temperature by Joule heat generated between the electrodes 31. Each electrode 31 is connected to an electrode moving mechanism (not shown) for moving the electrode 31, and the electrode 31 is arranged at a predetermined position when the workpiece W is heated by this electrode moving mechanism. In addition, when the workpiece W is pressed, it can be retracted from between the upper die 12 and the lower die 13.

  Also, as shown in FIG. 3, a plurality of air blow nozzles 32 are arranged at substantially equal intervals (approximately 20 to 40 mm intervals) on both sides in the short direction of the workpiece W (corresponding to portions that become flange portions after press molding). ing. In the present embodiment, the air blow nozzles 32 are arranged in a straight line. Note that the number and arrangement of the air blow nozzles 32 are determined by the shape of the press-formed product and the location where quenching is performed. As shown in FIG. 4, the air blow nozzle 32 is integrally provided with a partition plate 33 that restricts an injection region of air that is a refrigerant. This makes it possible to accurately set the refrigerant injection region with a very simple configuration and eliminates the need to separately arrange the nozzle 32 and the partition plate 33, thereby forming a predetermined temperature distribution on the workpiece W. The time required to do so can be shortened.

  Here, in order to limit the air injection region of the air blow nozzle 32, a suction nozzle 34 may be provided instead of the partition plate 33 as shown in FIG. By providing such a suction nozzle 34, the air jet region that is about to flow out of the suction nozzle 34 is sucked by the suction nozzle 34, whereby the air injection region can be limited to a certain range, and the workpiece W can be accurately applied. A quenching region R1 and a non-quenching region R2 can be formed.

  Alternatively, as shown in FIG. 6, a nozzle injection angle variable unit 35 that varies the air injection angle of the air blow nozzle 32 may be provided. By providing such a nozzle injection angle variable unit 35 and inclining the injection angle of air injected from the air blow nozzle 32 toward the outside of the quenching region R1 of the workpiece W, the air injection region is limited to a certain range. Thus, the hardened region R1 and the non-hardened region R2 can be accurately formed on the workpiece W. Note that the air injection angle is inclined in a direction inclined with respect to the workpiece W, not in a direction orthogonal to the workpiece W.

  Each air blow nozzle 32 is connected to a nozzle moving mechanism (not shown) for moving the air blow nozzle 32. When the work W is cooled (heating control) by this nozzle moving mechanism, the air blow nozzle 32 is moved. While being able to arrange | position in arbitrary positions, when press-working the workpiece | work W, it can retract | save from between the upper mold | type 12 and the lower mold | type 13. Thereby, a cooling area | region (non-hardening area | region) can be arbitrarily set with the injection air from the air blow nozzle 32. FIG.

  The operation of the various mechanisms described above is controlled by a control unit (not shown) that controls the molding apparatus 10 in an integrated manner. The control unit also controls the energization time to the electrode 31, the injection time of the air blow nozzle 32, and the like.

  Next, a hot press forming method using the above-described forming apparatus 10 will be described with reference to FIGS. 1 and 7 to 9. FIG. 7 is a diagram illustrating a state in which a predetermined temperature distribution is formed (heating control) on the workpiece. FIG. 8 is a perspective view showing a press-molded product. FIG. 9 is a cross-sectional view showing a press-formed molded product.

  First, a substantially flat workpiece W is set at a predetermined position of the forming apparatus 10, and electrodes 31 are arranged on both sides of the workpiece W in the longitudinal direction. Along with the arrangement of the electrodes 31, the air blow nozzles 32 are also arranged at predetermined positions. The arrangement of the electrode 31 and the air blow nozzle 32 is performed by operation control of each mechanism by the control unit of the molding apparatus 10. In addition, the data regarding the arrangement positions of the electrode 31 and the air blow nozzle 32 are stored in advance in the control unit of the molding apparatus 10 based on the size and shape of the workpiece W, the shape of the molded product, and the like, depending on the workpiece to be molded. The electrode 31 and the air blow nozzle 32 are automatically arranged at predetermined positions.

  Here, in this embodiment, the substantially flat workpiece W is formed into a hat shape in the cross section shown in FIG. 8 (a shape in which flanges projecting outward at both ends of the U-shaped cross section are integrally formed), and the flanges on both sides are formed. Hot press molding is performed to prevent quenching. For this reason, since it is necessary to cool the part (both ends in the short direction of the work W) that become flanges after press molding (so as not to be heated), as shown in FIG. The air blow nozzles 32 are linearly arranged at substantially equal intervals.

  Then, the electrodes 31 are energized under the control of the control unit of the forming apparatus 10, and the workpiece W is heated to a temperature higher than the quenching temperature by Joule heat generated between the electrodes 31. At this time, air is ejected from each air blow nozzle 32 to cool both ends of the work W in the short direction. Here, since each air blow nozzle 32 is integrally provided with a partition plate 33 that restricts the air injection region, it is possible to accurately partition the air injection region and the air non-injection region in the workpiece W. it can. Although there is a gap of about 20 to 40 mm between the adjacent air blow nozzles 32, this portion is a change-over area, so that it does not exceed the quenchable temperature. As a result, since a desired temperature distribution can be formed on the workpiece W, the workpiece W is quenched between the electrodes 31 as shown in FIG. (Hatched portion) and a non-quenched region R2 (non-hatched portion) that is maintained (cooled) at a temperature lower than the AC1 point are formed with high accuracy.

  When the quenching region R1 and the non-quenching region R2 are thus formed on the workpiece W, the electrode 31 and each air blow nozzle 32 are controlled by the control unit of the molding apparatus 10 so that the upper mold 12 and the lower mold 13 are controlled. Evacuated from between. And the upper mold | type 12 descend | falls and the protrusion part 12a of the upper mold | type 12 and the recessed part 13a of the lower mold | type 13 are combined. Thereby, the workpiece | work W is press-molded by the cross-sectional hat shape. At this time, in the quenching region R <b> 1 of the workpiece W, the upper mold 12 and the lower mold 13 are rapidly deprived of heat and rapidly cooled. Thereby, quenching is performed on the quenching region R1 of the workpiece W. Thereafter, the molded workpiece W is taken out from the molding apparatus 10. As shown in FIGS. 8 and 9, the molded product 40 thus manufactured includes a flange portion 41 and is formed in a cross-sectional hat shape. In the molded product 40, as shown in FIG. 8, the head portion 42 and the side portion 43 are quenched (hatched portion), and the flange portion 41 is not quenched.

  Here, since the hardness in each part of the molded article 40 having a hat-shaped cross section created as described above was measured, the measurement result is shown in FIG. FIG. 10 is a diagram showing the hardness of each part of a press-molded molded product. Note that the measurement positions (1) to (19) shown in FIG. 10 correspond to the numbers (1) to (19) shown in FIG.

  As is clear from FIG. 10, the measurement positions (8) to (12) corresponding to the head portion 42 of the molded product 40 and the measurement positions (4) to (7) and (13) to (13) corresponding to the side portion 43. In 16), as a result of quenching, the hardness is high and high tensile. On the other hand, at the measurement positions (1) to (3) and (17) to (19) corresponding to the flange portion 41 of the molded product 40, the hardness is low and not high-tensile as a result of not being quenched. As described above, according to the molding apparatus 10, only the necessary portions (the head portion 42 and the side portion 43) of the molded product 40 can be quenched to increase the tensile strength.

  Thereafter, the two molded products 40 are welded by, for example, spot welding or the like, with the flange portions 41 being overlapped with each other. Further, post-cutting processing is performed on the joined flange portion 41 as necessary. As a result, an automotive structural component having a hollow closed cross section and a flange portion extending outward from the closed cross section is completed. And since the flange part 41 is not hardened, favorable welding quality is ensured and it is excellent also in the post-drawing workability.

  And in the shaping | molding apparatus 10 which concerns on this Embodiment, since each air blow nozzle 32 can be arrange | positioned in arbitrary positions, the non-hardening area | region which is not heated to the quenchable temperature in a workpiece | work is formed arbitrarily arbitrarily. Can do. Accordingly, for example, even in the case of the molded products 45 and 46 having a hat-shaped cross section curved in the longitudinal direction as shown in FIG. 11 and FIG. 13, only the portion that needs to be high-tensified (hatched portion: quenching region R1). Quenching can be performed. In this case, as shown in FIGS. 12 and 14, the air blow nozzles 32 may be arranged so as to draw a predetermined curvature. The molded product 45 is molded from a substantially rectangular workpiece W as shown in FIG. 12, and the molded product 46 is molded from a generally arcuate workpiece Wa as shown in FIG.

  Further, since the molding apparatus 10 is a non-contact method in which the temperature of the workpiece is controlled (cooled) by injecting air, instead of removing heat by bringing a masking or conveying device into contact, it seems that the workpiece has a step. Even if it is a simple shape, by adjusting the arrangement height of the air blow nozzle 32, it is possible to easily and accurately form a desired temperature distribution on the workpiece. Therefore, even in such a case, it is possible to accurately quench only the portion that needs to be high-tensified.

  As described above in detail, according to the molding apparatus 10 according to the present embodiment, the workpiece W is heated by the electrode 31 to a temperature higher than or equal to the quenchable temperature and is ejected from the air blow nozzle 32 before press molding. The temperature of the both ends in the short direction of the workpiece W (the portion corresponding to the flange portion 41) is maintained in a state lower than the quenchable temperature by the air. Thereby, only the part (part corresponding to the head part 42 and the side part 43) by which intensity | strength is requested | required among the workpiece | work W can be heated more than the quenchable temperature. That is, a predetermined temperature distribution can be appropriately formed on the workpiece W. Then, the workpiece W controlled in this manner is press-molded by the upper mold 12 and the lower mold 13 at room temperature, and the portion of the workpiece W heated to a temperature that can be hardened or higher (the head 42 and the side). Part 43) is quenched. Thereby, it is possible to form the molded product 40 having a hat-shaped cross section in which only the head portion 42 and the side portion 43 that require strength are quenched.

  And, in the molding apparatus 10 according to the present embodiment, since it is a non-contact method that controls (cools) the temperature of the workpiece by injecting air rather than contacting the masking or conveying device to remove heat, Even if the workpiece has a complicated shape such as, a predetermined temperature distribution can be accurately formed on the workpiece. Moreover, an air injection area | region (non-hardening area | region R2) can be arbitrarily set only by changing the arrangement position of the air blow nozzle 32. FIG. Therefore, it is possible to form molded products having various shapes while quenching only in a portion where high strength is required.

  It should be noted that the above-described embodiment is merely an example and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, the case where the pressing is performed in the shape of a cross-sectional hat is illustrated, but the present invention can also be applied to pressing or drawing with other shapes. Further, in the above-described embodiment, the case where the present invention is applied to the molding of automobile structural parts has been exemplified. However, the present invention is not limited to automobile structural parts, and is widely applied to steel plate products that require separate production of strength. can do.

  Furthermore, in the above-described embodiment, the heating control of the workpiece is performed only by air injection, but the heating control of the workpiece can also be performed using this in combination with heat removal by a cooling pad or the like.

In the above-described embodiment, the workpiece W is heated between the upper mold 12 and the lower mold 13. However, the present invention is not limited to this, and the workpiece W is separated from the upper mold 12 and the lower mold 13 as shown in FIG. It is also possible to heat the workpiece W at the position and transport the heated workpiece W between the upper die 12 and the lower die 13 to perform press molding.
Furthermore, in the above-described embodiment, the case where both ends in the longitudinal direction of the workpiece W are cooled is exemplified as the heating control of the workpiece W. However, the present invention is not limited to this. For example, as shown in FIG. An air blow nozzle 32 can be arranged at a place to be performed, and this portion can be cooled. Thereby, post-cutting can be performed with high accuracy. In addition, arrangement | positioning of the air blow nozzle 32 as shown in FIG. 16 and arrangement | positioning of the air blow nozzle 32 in above-mentioned embodiment can also be combined arbitrarily.

DESCRIPTION OF SYMBOLS 10 Molding apparatus 11 Press work part 12 Upper mold | type 12a Protrusion part 13 Lower mold | type 13a Concave part 30 Work heating part 31 Electrode 32 Air blow nozzle 33 Partition plate 34 Suction nozzle 35 Nozzle injection angle variable unit 40 Molded product 41 Flange part 42 Head 43 side Part R1 Quenching area R2 Non-quenching area W Workpiece

Claims (8)

In the hot press molding method in which quenching is performed by cooling while performing press molding after heating the molding material according to the required strength of each part of the molded product,
A heating process for heating the molding material to a temperature higher than the quenching temperature;
A heating control step of performing heating control of the molding material so as to lower the heating temperature locally than the quenchable temperature by injecting a refrigerant to any part of the molding material being heated by the heating step;
A hot press molding method comprising: In the hot press molding method according to claim 1,
In the heating control step, the hot press molding method is characterized in that the heating temperature of the molding material is locally lower than the quenchable temperature by limiting the injection region of the refrigerant. In the hot press molding method according to claim 1,
The heating control step is characterized in that the heating temperature of the molding material is locally lower than the quenchable temperature by inclining the injection angle of the refrigerant with respect to the molding material in the outer direction of the quenching portion. Hot press molding method. In a hot press molding apparatus that performs quenching by cooling while performing press molding after heating control of the molding material according to the required strength of each part of the molded product,
Heating means for heating the molding material to a temperature higher than the quenching temperature;
Refrigerant injection means for injecting a refrigerant to any part of the molding material being heated by the heating means;
Limiting means for limiting the injection region of the refrigerant injected from the refrigerant injection means to the molding material;
A hot press molding apparatus characterized by comprising: In the hot press molding apparatus according to claim 4,
The hot press molding apparatus according to claim 1, wherein the limiting means is a partition plate that partitions a refrigerant injection region and a refrigerant non-injection region in the molding material. In the hot press molding apparatus according to claim 4,
The hot press molding apparatus according to claim 1, wherein the limiting means is a refrigerant suction means for sucking a refrigerant flowing in a refrigerant non-injection region of the molding material. In the hot press molding apparatus according to claim 5 or 6,
The hot press molding apparatus according to claim 1, wherein the limiting means is provided integrally with the refrigerant injection means. In the hot press molding apparatus according to claim 4,
The hot press characterized in that the limiting means is a control means for controlling the injection direction of the refrigerant injection means so as to incline the injection angle of the refrigerant with respect to the molding material in the outward direction of the quenched portion of the molding material. Molding equipment.

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