JP7374148B2 - Hot press molding mold, method for manufacturing hot press molding mold, and manufacturing method for automobile body parts - Google Patents

Description

The present invention relates to a hot press molding die having a refrigerant passage therein, a method for manufacturing the hot press molding die, and a method for manufacturing automobile body parts.

BACKGROUND ART Hot press molding (hot stamping method) is known as a technique for molding body parts of vehicles such as automobiles. This hot stamping method is a method in which a metal plate heated to a high temperature is loaded into a hot press molding device, and the metal plate is press-molded and simultaneously quenched. A conventional hot press molding device that can be used to implement this type of hot stamping method is described in, for example, Patent Document 1.

A conventional hot press molding apparatus such as that disclosed in Patent Document 1 employs a configuration in which a refrigerant is flowed through a refrigerant passage formed in the mold in order to maintain the temperature of the hot press mold at a low temperature. It is being The refrigerant passage is configured using holes drilled in the mold by machining. This hole is formed as shown in FIG. 12, for example.

A hot press molding die 1 shown in FIG. 12 has a molding surface 2 for molding a metal plate material (not shown), and a refrigerant passage 4 consisting of a plurality of holes 3 formed by machining. . The refrigerant passage 4 has a main cooling passage 4a extending along the molding surface 2, and a communication passage 4b extending in a direction opposite to the molding surface 2 from the middle of the main cooling passage 4a. The communication passage 4b is a passage for communicating the main cooling passage 4a with a refrigerant discharge passage (not shown), a refrigerant passage of another adjacent hot press mold, or the like.

The refrigerant flows into the main cooling passage 4a from the left end of the main cooling passage 4a in FIG. 12, and flows from the main cooling passage 4a into the communication passage 4b. At this time, the refrigerant comes to stay in the extension portion 4c of the main cooling passage 4a that extends beyond the communication passage 4b. When the refrigerant stays in the extension part 4c, a "heat pool" is generated in the part shown by the thick line in FIG. 12, that is, in the part 2a of the molding surface 2 adjacent to the extension part 4c.

JP 2018-12113 Publication

When "heat accumulation" occurs in the hot press molding die 1 shown in FIG. 12, heat exchange between the molding surface 2 and the refrigerant becomes insufficient. In FIG. 12, an image of heat exchange is shown by a white arrow. If heat exchange is insufficient, the part 2a of the molding surface 2 that becomes a "heat pool" cannot be sufficiently cooled, and the metal plate material (molded product) that comes into contact with the part 2a of the molding surface 2 cannot be sufficiently cooled during molding. It becomes impossible to cool down.

There are two main reasons why "heat accumulation" occurs due to refrigerant retention inside the hot press molding die 1, as described below.
The first reason is that the refrigerant passage 4 cannot be set for design reasons. That is, it may not be possible to form the holes 3 that will become the refrigerant passages 4 depending on the shape and size of the mold parts or the mold.
The second reason is that the refrigerant passage 4 cannot be set due to machining. That is, depending on the diameter, length, performance, etc. of the drill used to drill the holes 3, the conditions of the intersecting portions of the holes 3, etc., it may not be possible to perform the machining as designed.

An object of the present invention is to provide a hot press molding die, a method for manufacturing the hot press molding die, and a method for manufacturing automobile body parts, which can prevent the formation of "heat accumulation" on the molding surface. The purpose is to

To achieve this object, the hot press molding mold according to the present invention includes at least one mold body formed of a hot press molding mold material, and a mold body formed on the surface of the mold body. , a molding surface for molding a heated metal plate material, a refrigerant passage formed inside the mold body through which a refrigerant flows, and a solid shape made of a material having higher thermal conductivity than the mold material; and a heat transfer body embedded in the mold body, the heat transfer body forming part of a heat transfer path from the molding surface to the refrigerant passage.
The present invention provides a mold for hot press molding, wherein the mold body has a side surface or an end surface in the front and back direction connected to the molding surface, and the heat transfer body is located near the molding surface and has a side surface connected to the molding surface. It may be provided between the refrigerant passage and the side surface or the end surface in the longitudinal direction.
In the hot press mold according to the present invention, one end of the heat transfer body may be exposed to an outer surface of the mold body, and the other end of the heat transfer body may be in contact with a coolant.

In the hot press molding mold of the present invention, the mold body is configured such that a plurality of the mold bodies can be connected to each other, and the refrigerant of the two mold bodies adjacent to each other is The passage passes from the inside of one of the mold bodies to the other of the mold bodies through the inside of a passage forming member provided on the outer surface of these mold bodies so as to extend from one of the mold bodies to the other of the mold bodies. The heat transfer body is configured to extend into the main body, and is a connection portion between two adjacent mold bodies, and the heat transfer body is provided near the molding surface.

In the hot press molding mold of the present invention, a mold component is attached to the mold body so as to protrude from the molding surface, and the refrigerant passage passes through the vicinity of the mold component. The heat transfer body may be formed to extend along the molding surface, and the heat transfer body may be arranged to sandwich the mold component from one direction and the other direction in which the coolant passage extends.

In the hot press molding die of the present invention, the heat transfer body may be formed of a copper material.
The present invention provides the hot press molding mold, wherein the mold body has a hole that opens on the outer surface and extends near the molding surface toward the refrigerant passage along the molding surface, and The heat transfer body may be press-fitted into the hole.
In the hot press mold according to the present invention, the heat transfer body may be constituted by a plurality of columnar bodies individually press-fitted into one of the holes.
In the hot press molding die of the present invention, the heat transfer body may have a threaded hole extending into the heat transfer body from an end surface that is an opening side of the hole.
The present invention provides the hot press molding mold, wherein the mold body has a hole that opens on the outer surface and extends near the molding surface toward the refrigerant passage along the molding surface, and A female thread may be formed in the hole, and the heat transfer body may be screwed into the female thread.

A method for manufacturing a hot press molding mold according to the present invention includes the steps of: forming a mold body using a mold material for hot press molding; forming a molding surface on the mold body; forming a refrigerant passage through which a refrigerant flows inside the mold body; and a step of forming a heat transfer body made of a material having a higher thermal conductivity than the mold material inside the mold body from the molding surface to the refrigerant passage. burying the heat transfer body in the mold body so as to form a part of a heat transfer passage toward the mold body; forming a hole extending toward the refrigerant passage; and driving the heat transfer body, which is formed into a solid shape so that it can be press-fitted into the hole, into the hole from an opening in the outer surface. This is the way to do it.

A method for manufacturing a hot press molding die according to the present invention includes a hot press forming die for forming a hot press molding die by casting, which has a forming surface for forming a heated metal plate material and a refrigerant passage through which a coolant flows. A method for manufacturing a press molding die, the method comprising: inserting a heat transfer body made of a steel pipe whose interior is filled with a metal material having higher thermal conductivity than the die material used for casting from the molding surface into the coolant passage. This is a method of embedding by casting in a position that will become part of the heat transfer path toward the destination.

The method for manufacturing an automobile body part according to the present invention includes the steps of stacking a metal plate material for an automobile body part heated to a predetermined temperature on the hot press molding die, and using the hot press forming die. This method is carried out by forming the metal plate material by a hot stamping method.

According to the hot press molding die according to the present invention, since the heat transfer body substantially functions as a refrigerant, by embedding the heat transfer body in a part where the refrigerant cannot flow, it is possible to flow the refrigerant. Even in areas where this is not possible, heat exchange can be performed with the refrigerant. Therefore, it is possible to provide a hot press molding mold that can prevent a portion where the refrigerant stays in the mold and a "heat accumulation" from occurring on the molding surface.

According to the method for manufacturing a hot press molding die in which the heat transfer body is driven into the die body, the heat transfer body is reliably attached to the die body. Therefore, the heat transfer body can be embedded in the mold body to increase the efficiency of heat exchange, and the heat exchange through the heat transfer body can be performed efficiently, eliminating "heat accumulation". I can do it.

According to the manufacturing method of a hot press molding die in which the heat transfer body is embedded in the mold body by casting, the embedding of the heat transfer body is completed at the time of casting. In comparison, the number of steps for manufacturing a hot press molding die is reduced, and the manufacturing cost of the hot press molding die can be reduced.

According to the method for manufacturing automobile body parts according to the present invention, since the metal plate material for automobile body parts is sufficiently cooled during molding, it is possible to manufacture automobile body parts with high strength.

FIG. 1 is a sectional view of a hot press molding die according to the present invention. FIG. 2 is a flowchart showing a method for manufacturing a hot press molding die according to the present invention. FIG. 3 is a perspective view showing a modification of the heat transfer body. FIG. 4 is a sectional view showing another embodiment of a hot press molding die. FIG. 5 shows another embodiment of the hot press molding die. FIG. 6 is a cross-sectional view for explaining a second embodiment of the method for manufacturing a hot press molding die. FIG. 7 is a flowchart showing a method for manufacturing a hot press molding die according to the second embodiment. FIG. 8 is a perspective view showing a modification of the heat transfer body. FIG. 9 is a perspective view showing a modification of the heat transfer body. FIG. 10 is a side view showing a modification of the heat transfer body. FIG. 11 is a flowchart for explaining the method for manufacturing automobile body parts according to the present invention. FIG. 12 is a sectional view of a conventional hot press molding die.

(First embodiment)
EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of a hot press molding die and a method for manufacturing a hot press molding die according to the present invention will be described in detail with reference to FIGS. 1 to 3.
A hot press molding die 11 shown in FIG. 1 is configured by providing a die body 12 with various functional parts described below. The mold body 12 is formed of a mold material for hot press molding. As this mold material, for example, carbon steel for machine structures, steel for hot press molds, etc. can be used.

A molding surface 13 is formed on the surface of the mold body 12 (the upper surface in FIG. 1). The molding surface 13 molds the heated metal plate W into a molded product by sandwiching it in cooperation with other molds. As the metal plate material W, for example, a metal plate material for automobile body parts can be used.
A coolant passage 14 is formed inside the mold body 12 and near the molding surface 13 . The refrigerant passage 14 is a passage through which a liquid refrigerant (not shown) flows. Note that the refrigerant includes gas as well as liquid. As the liquid coolant, water, a coolant containing a chemical, or the like can be used. Air, nitrogen, or the like can be used as the gaseous refrigerant.

The coolant passage 14 shown in FIG. 1 is a main cooling passage 14a extending from one side 12a of the mold body 12 located on the left side of FIG. and a communication passage 14b extending from the main cooling passage 14a toward the bottom surface 12c on the opposite side to the molding surface 13. The communication passage 14b is a passage for communicating the main cooling passage 14a with a refrigerant discharge passage (not shown) or a refrigerant passage of another adjacent hot press molding die. The main cooling passage 14a and the communication passage 14b are formed by machining using, for example, a drill.
The coolant passages 14 are arranged at predetermined intervals in a direction along the molding surface 13 and perpendicular to the direction in which the main cooling passage 14 extends (a direction perpendicular to the plane of the paper in FIG. 1). It is provided.

The communication path 14b is formed at a position separated from the other side surface 12b of the mold body 12 by a predetermined length. The reason why the communicating path 14b is formed apart from the other side surface 12b in this manner is that if the communicating path 14b is formed close to the other side surface 12b, the rigidity of the mold body 12 will be reduced. In this mold body 12, a heat transfer body 15 is buried near the molding surface 13 and between the communicating path 14b and the other side surface 12b. The heat transfer body 15 is formed by a cylindrical pin 16 (see FIG. 3(A)) made of a material with higher thermal conductivity than the mold material, and is inserted into the pin hole 17 formed in the mold body 12. It is driven in from the outside of 12 and press-fitted.

The pin hole 17 opens on the outer surface (the other side surface 12b) of the mold body 12 and extends inside the mold body 12 near the molding surface 13 toward the coolant passage 14 along the molding surface 13. The tip of the pin hole 17 according to this embodiment opens at a portion where the main cooling passage 14a and the communication passage 14b intersect. Therefore, the heat transfer body 15 extends along the molding surface 13 from the other side surface 12b of the mold body 12 toward the coolant passage 14. The tip of the heat transfer body 15 is in contact with the refrigerant. Although not shown, the pins 16 and pin holes 17 are aligned with all other refrigerant passages 14 provided in the mold body 12 so as to be lined up in a direction perpendicular to the direction in which the main cooling passage 14a extends. are provided at corresponding positions.
The heat transfer body 15 embedded in the mold body 12 in this manner forms part of a heat transfer path 18 extending from the molding surface 13 to the coolant passage 14.

The material forming the heat transfer body 15 according to this embodiment is a copper material. The copper material here includes pure copper and copper alloy. When the heat transfer body 15 is formed of a copper alloy, it is preferable to use tellurium copper or tough pitch copper. Note that the heat transfer body 15 can be formed of gold, silver, aluminum, tungsten, duralumin, beryllium, magnesium, molybdenum, zinc, etc. in addition to copper material.

In order to manufacture the hot press molding die 11 according to this embodiment, as shown in the flowchart of FIG. S1). Next, a molding surface 13 is formed on the mold body 12 (step S2), and a refrigerant passage 14 is formed inside the mold body 12 (step S3). Thereafter, the mold body 12 is subjected to heat treatment (step S4), and the heat transfer body 15 is embedded inside the mold body 12 (step S5).

Step S5 of embedding the heat transfer body 15 in the mold body 12 is performed by step S5A of forming the pin hole 17 and step S5B of driving the heat transfer body 15 into the pin hole 17. The pin hole 17 can be formed from the other side surface 12b of the mold body 12 by, for example, a drill. The heat transfer body 15 has an outer diameter that can be press-fitted into the pin hole 17, and is driven into the pin hole 17 from the opening of the pin hole 17.

As the refrigerant flows through the refrigerant passage 14 of the hot press molding die 11 formed in this way, the heat of the molding surface 13 located near the main cooling passage 14a of the refrigerant passage 14 is transferred to the refrigerant by conduction. Ru. In addition, the heat of the molding surface 13 located near the heat transfer body 15 is transmitted to the portion between the molding surface 13 of the mold body 12 and the heat transfer body 15, as shown by the white arrow in FIG. The heat is transmitted to the heat transfer body 15 by conduction through the heat transfer body 15, and further transferred to the refrigerant via the heat transfer body 15. As a result, the entire area of the molding surface 13 is cooled substantially uniformly.

According to the hot press molding die 11 according to this embodiment, since the heat transfer body 15 substantially functions as a refrigerant, by embedding the heat transfer body 15 in a part where the refrigerant cannot flow, the refrigerant Even in areas where refrigerant cannot flow, heat exchange can be performed with the refrigerant. Therefore, it is possible to provide a hot press molding die that can prevent "heat accumulation" from occurring on the molding surface 13.

Furthermore, according to the method for manufacturing a hot press molding die according to this embodiment, since the heat transfer body 15 is driven into the die body 12, the heat transfer body 15 is reliably attached to the die body 12. Therefore, the heat transfer body 15 can be embedded in the mold body 12 so as to increase the efficiency of heat exchange.

Furthermore, by adopting a configuration in which one end of the heat transfer body 15 is exposed to the other side surface 12b of the mold body 12 as shown in FIG. 1, heat is dissipated from one end of the heat transfer body 15 into the atmosphere, thereby cooling Higher efficiency.

(Modified example of heat transfer body)
The heat transfer body 15 can be formed as shown in FIGS. 3(A) to 3(G).
The heat transfer body 15 shown in FIG. 3(A) is the pin 16 used when adopting the embodiment described above, and is formed in a columnar shape.
The heat transfer body 15 shown in FIG. 3(B) is formed by a conical pin 22. The heat transfer body 15 shown in FIG. The conical pin 22 is driven into the pin hole 17 so that its apex is located inside the pin hole 17.
The heat transfer body 15 shown in FIG. 3(C) is formed by a pin 23 in the shape of a truncated cone. The truncated conical pin 23 is driven into the pin hole 17 so that the thin part is located inside the pin hole 17.
The heat transfer body 15 shown in FIG. 3(D) is formed by a pin 24 having one end formed in the shape of a truncated cone. The pin 24 is driven into the pin hole 17 such that one end of the truncated cone is located inside the pin hole 17.
The heat transfer body 15 shown in FIG. 3(E) is formed by a square columnar pin 26. The heat transfer body 15 shown in FIG.
The heat transfer body 15 shown in FIG. 3(F) is formed into a square pyramid-shaped pin 27.
The heat transfer body 15 shown in FIG. 3(G) is formed by a pin 28 in the shape of a truncated quadrangular pyramid. When using a heat transfer body 15 having a square cross section as shown in FIGS. It is molded using a core (not shown) so that it becomes .

(Second embodiment)
The hot press molding die according to the present invention can be configured as shown in FIG. In FIG. 4, the same or equivalent members as those explained with reference to FIGS. 1 to 3 are given the same reference numerals, and detailed explanations are omitted as appropriate.
A hot press molding die 31 shown in FIG. 4 is constructed by combining a plurality of die bodies 12. The mold body 12 according to this embodiment is configured such that a plurality of mold bodies 12 can be connected to each other. FIG. 4 shows a hot press molding die 31 in which two die bodies 12, 12 are connected. Hereinafter, the mold body 12 located on the left side in FIG. 4 will be referred to as "one mold body 12A" for convenience, and the mold body 12 located on the right side will be referred to as "the other mold body 12B" for convenience.

The structures of these mold bodies 12A and 12B are the same as the mold body 12 shown in FIG. That is, the mold bodies 12A, 12B are formed with a molding surface 13 and a coolant passage 14, and are also provided with a heat transfer body 15. The other mold body 12B is obtained by inverting the one mold body 12A so that one side is located on the opposite side. The one mold body 12A and the other mold body 12B are connected to each other by a connection mechanism (not shown) such that their side surfaces are in close contact with each other.
The heat transfer body 15 is a connecting portion between these mutually adjacent mold bodies 12A and 12B, and is provided near the molding surface 13.

Further, on the bottom surfaces of these mold bodies 12A and 12B, a passage forming member 32 is provided so as to extend from one mold body 12A to the other mold body 12B. A refrigerant passage 33 is formed inside the passage forming member 32 to connect the refrigerant passage 14 of one mold body 12A and the refrigerant passage 14 of the other mold body 12B. One end of this refrigerant passage 33 is connected to the communication passage 14b of one mold body 12A. Further, the other end of this refrigerant passage 33 is connected to the communication passage 14b of the other mold body 12B. Therefore, the refrigerant that has flowed through one refrigerant passage 14 flows into the refrigerant passage 14 of the other mold body 12B via the refrigerant passage 33 of the passage forming member 32.

In the hot press molding die 31 according to this embodiment, the heat near the contact surfaces of the two mutually adjacent die bodies 12A and 12B can be transferred to the coolant by the heat transfer body 15. Therefore, it becomes possible to cool the joints between the mold bodies 12, where it was not possible to form the refrigerant passages 14 in the past.

(Third embodiment)
The hot press molding die according to the present invention can be configured as shown in FIGS. 5(A) and 5(B). In FIGS. 5A and 5B, members that are the same or equivalent to those described with reference to FIGS. 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate. FIG. 5(A) is a side view of the hot press molding die, and FIG. 5(B) is a sectional view taken along the line VV in FIG. 5(A).

The hot press molding die 41 shown in FIGS. 5(A) and 5(B) includes a die component 42 attached to the die body 12 so as to protrude from the molding surface 13. An example of the mold component 42 is a pilot pin. The molding surface 13 is formed in a rectangular shape that is elongated in the left-right direction in FIGS. 5(A) and 5(B). The mold component 42 is located in the center of the molding surface 13 in the left-right direction, and is located at a position biased toward one side of the front-to-back direction perpendicular to the left-right direction (downward in FIG. 5(B)). In the following, one of the front and rear directions where the mold component 42 is located will be referred to as the front.

Since the mold part 42 is disposed biased toward the front of the mold body 12 in this way, the space in front of the mold part 42 of the mold body 12 is narrow, making it impossible to form the refrigerant passage 14. . Therefore, the refrigerant passage 14 is formed at the rear of the mold body 12 than the mold component 42 . The refrigerant passage 14 according to this embodiment is a straight line passing near the rear of the mold part 42 and along the molding surface 13 from one side surface 12a (left side in FIG. 5) to the other side surface 12b of the mold body 12. It is formed to extend.

The heat transfer body 15 according to this embodiment is arranged so as to sandwich the mold component 42 from one side and the other side in the direction in which the refrigerant passage 14 extends (left-right direction). Specifically, the heat transfer body 15 is constituted by a cylindrical pin 16 formed to extend from the front surface 12d of the mold body 12 to the coolant passage 14, and is arranged at a plurality of positions at predetermined intervals in the left-right direction. are provided in each. By arranging the heat transfer body 15 in this manner, heat can be transferred to the refrigerant from substantially the entire area of the molding surface 13. Note that, in addition to the cylindrical pin 16, a heat transfer body 15 having a shape as shown in FIG. 3 can be used.

(Fourth embodiment)
The method for manufacturing a hot press molding die according to the present invention can be carried out as shown in FIGS. 6 and 7. In FIG. 6, the same or equivalent members as those explained with reference to FIGS. 1 to 3 are given the same reference numerals, and detailed explanations are omitted as appropriate.
The mold body 12 of the hot press molding mold 51 shown in FIG. 6 is formed into a predetermined shape by casting. The refrigerant passage 14 according to this embodiment is formed by casting using a core (not shown).

The heat transfer body 15 provided in this hot press molding die 51 is formed of a steel pipe 53 whose interior is filled with a metal material 52 having a higher thermal conductivity than the die material used for casting. Examples of the metal material 52 include gold, silver, pure copper, copper alloy, aluminum, tungsten, duralumin, beryllium, magnesium, molybdenum, and zinc. This heat transfer body 15 is embedded in the mold by casting when the hot press molding mold 51 is cast.

The hot press molding die 51 can be manufactured as shown in the flowchart shown in FIG. In order to manufacture the hot press molding die 51, first, a mold (not shown) for casting is prepared (step P1). In this step, the core for forming the refrigerant passages 14 is assembled into the mold. Next, the heat transfer body 15 is loaded into the mold cavity. At this time, the heat transfer body 15 is placed at a position that becomes a part of the heat transfer path 18 from the molding surface to the coolant passage 14 . Also in this embodiment, the heat transfer body 15 is arranged so as to extend along the molding surface 13.
After the heat transfer body 15 is assembled into the mold in this way, a molten metal (not shown) made of mold material is poured into the cavity and casting is performed (step P3). As the molten metal solidifies within the cavity during casting, the heat transfer body 15 is embedded in a predetermined position by casting.

Therefore, even when the hot press molding die 51 is manufactured by casting as shown in this embodiment, since the heat transfer body 15 mediates the transfer of heat, "heat accumulation" occurs on the molding surface 13. It is possible to prevent this from occurring.
Further, according to the manufacturing method according to this embodiment, that is, the manufacturing method of the hot press molding die 51 in which the heat transfer body 15 is embedded in the mold body 12 by casting, the embedding of the heat transfer body 15 is completed at the time of casting. Therefore, compared to the manufacturing method in which the heat transfer body 15 is driven into the mold body 12, the number of steps for manufacturing the hot press molding mold 51 is reduced, and the manufacturing cost of the hot press molding mold 51 is reduced. can be reduced. Furthermore, according to the manufacturing method according to this embodiment, since the thermal resistance is increased by the steel pipe 53, the difference between the melting point of the metal material 52 in the steel pipe 53 and the melting point of the mold material used for casting is small. Also, the metal material 52 becomes difficult to melt.

(Modified example of heat transfer body)
The heat transfer body used in the above-described embodiment can be formed as shown in FIGS. 8 to 10. In FIGS. 8 to 10, members that are the same or equivalent to those described in FIGS. 1 to 6 are designated by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.
In the heat transfer body 15 shown in FIG. 8, one cylindrical pin 16 is divided in the longitudinal direction into three columnar bodies 15a to 15c. These columnar bodies 15a to 15c are individually driven into one pin hole 17.
By adopting this configuration, the load during driving can be reduced, and the driving work becomes easier.

The heat transfer body 15 shown in FIG. 9(A) is configured by forming a screw hole 16a in the axial center of a cylindrical pin 16. When driving the heat transfer body 15 into the pin hole 17, a bolt 16b is screwed into the screw hole 16a and the bolt 16b is struck with a tool (not shown). When the screw hole 16a is formed in this way, after the heat transfer body 15 is driven into the pin hole 17, the bolt 16b is screwed into the screw hole 16a, and by pulling this bolt 16b, the heat transfer body 15 can be attached to the metal. It can be extracted from the mold body 12. Therefore, it becomes easy to remove the heat transfer body 15 from the mold body 12 during maintenance or the like.

The heat transfer body 15 shown in FIG. 9(B) is obtained by dividing one cylindrical pin 16 in the longitudinal direction into two columnar bodies 15a and 15b. A screw hole 16a is formed in the axial center of these columnar bodies 15a, 15b. The columnar bodies 15a, 15b are individually driven into one pin hole 17. When driving the pillar-like bodies 15a and 15b into the pin hole 17, the bolt 16 is screwed into the screw hole 16b and the bolt 16 is struck with a tool, as shown in FIG. 9(C). Further, when the columnar bodies 15a, 15b are to be removed from the mold body 12 for maintenance or the like, a bolt 16b is screwed into the screw hole 16a and the bolt 16b is pulled.
By adopting this configuration, the load at the time of driving can be reduced, and the operation of extracting the columnar bodies 15a, 15b from the mold body 12 can be easily performed with a small load.
Although FIGS. 8 and 9 show an example in which a screw hole 16a is formed in the heat transfer body 15 consisting of a cylindrical pin 16 or the pin 16 is divided, the configuration shown in FIGS. 8 and 9 is adopted. In this case, the pin 16 is not limited to a cylindrical shape. That is, the heat transfer body 15 may have a shape as shown in FIGS. 3(B) to 3(G).
Good too.

The heat transfer body 15 shown in FIG. 10 is formed by a hexagon socket set screw 61, and has a hexagon socket 62 at one end for engaging a tool (not shown). When using this heat transfer body 15, a female thread (not shown) is formed in the pin hole 17. Note that the screw type heat transfer body 15 can also be constructed by forming male threads on the pins 16, 21 to 24 having shapes as shown in FIGS. 3(A) to 3(D).

By adopting a configuration in which the heat transfer body 15 is attached to the mold body 12 with screws in this way, it becomes possible to remove the heat transfer body 15 from the mold body 12 during maintenance, for example, and maintenance can be easily performed. .

(Fifth embodiment)
In order to manufacture an automobile body part using the hot press molding die shown in the embodiment described above, the process can be carried out as shown in the flowchart of FIG. 11. In addition, in the following, members that are the same as or equivalent to those explained with reference to FIG.

In order to manufacture an automobile body part using the hot press molding die 11 according to the embodiment described above, first, a metal material W for an automobile body part is laid on the molding surface 13 (step P10). Then, the metal material W is sandwiched between the mold body 12 having the molding surface 13 and another mold, and the metal material W is molded by a hot stamping method (step P11).

The hot press molding die 11 according to the embodiment described above does not cause "heat accumulation" on the molding surface 13. Therefore, according to this method for manufacturing automobile body parts, since the metal material W for automobile body parts is sufficiently cooled during molding, it is possible to manufacture automobile body parts with high strength.

DESCRIPTION OF SYMBOLS 1, 51... Hot press mold, 12... Mold body, 12c... Bottom surface, 13... Molding surface, 14... Refrigerant passage, 15... Heat transfer body, 18... Heat transfer path, 17... Pin hole, 42 ...Mold parts, 52...Metal material, 53...Steel pipe, W...Metal plate material.

Claims (13)

at least one mold body formed of a mold material for hot press molding;
a molding surface formed on the surface of the mold body and molding the heated metal plate material;
a refrigerant passage formed inside the mold body, through which a refrigerant flows;
a heat transfer body formed in a solid shape from a material having higher thermal conductivity than the mold material and embedded in the mold body;
A mold for hot press molding, wherein the heat transfer body constitutes a part of a heat transfer path from the molding surface to the coolant passage. The hot press molding mold according to claim 1,
The mold body has a side surface or an end surface in the front-rear direction that connects to the molding surface,
The hot press molding die is characterized in that the heat transfer body is provided near the molding surface and between the refrigerant passage and the side surface or the end surface in the front-rear direction. The hot press molding mold according to claim 1 or 2,
A mold for hot press molding, wherein one end of the heat transfer body is exposed on the outer surface of the mold body, and the other end of the heat transfer body is in contact with a coolant. In the hot press molding mold according to any one of claims 1 to 3 ,
The mold body is configured such that a plurality of mold bodies can be connected to each other,
The refrigerant passages of the two mold bodies adjacent to each other pass through the inside of a passage forming member provided on the outer surface of these mold bodies so as to extend from one mold body to the other mold body. configured to extend from one mold body into the other mold body,
A mold for hot press molding, characterized in that the heat transfer body is provided in the connecting portion of the two mold bodies adjacent to each other and in the vicinity of the molding surface. In the hot press molding mold according to any one of claims 1 to 4,
A mold component is attached to the mold body so as to protrude from the molding surface,
The refrigerant passage is formed to extend along the molding surface passing near the mold component,
A mold for hot press molding, wherein the heat transfer body is arranged to sandwich the mold component from one side and the other side in the direction in which the refrigerant passage extends. In the hot press molding mold according to any one of claims 1 to 5 ,
A mold for hot press molding, wherein the heat transfer body is formed of a copper material. In the hot press molding mold according to any one of claims 1 to 6,
The mold body has a hole that opens on the outer surface and extends near the molding surface toward the refrigerant passage,
A mold for hot press molding, wherein the heat transfer body is press-fitted into the hole. The hot press molding mold according to claim 7,
A mold for hot press molding, wherein the heat transfer body is constituted by a plurality of columnar bodies individually press-fitted into one of the holes. The hot press mold according to claim 7 or 8,
A mold for hot press molding, wherein the heat transfer body has a threaded hole extending into the inside of the heat transfer body from an end surface that is an opening side of the hole. In the hot press molding mold according to any one of claims 1 to 6,
The mold body has a hole that is open to the outer surface and extends near the molding surface toward the refrigerant passage along the molding surface,
a female thread is formed in the hole;
A mold for hot press molding, wherein the heat transfer body is screwed into the female thread. forming a mold body using a mold material for hot press molding;
forming a molding surface on the mold body;
forming a refrigerant passage through which a refrigerant flows inside the mold body;
burying a heat transfer body made of a material having higher thermal conductivity than the mold material inside the mold body so as to constitute a part of a heat transfer passage from the molding surface to the refrigerant passage; has
embedding the heat transfer body in the mold body,
forming a hole that opens on the outer surface of the mold body and extends within the mold body toward the coolant passage;
Manufacturing a mold for hot press molding, characterized in that the step of driving the heat transfer body, which is formed into a solid shape so that it can be press-fitted into the hole, into the hole from an opening in the outer surface. Method. A method for manufacturing a hot press molding mold, which comprises molding by casting a hot press molding mold having a molding surface for molding a heated metal plate material and a refrigerant passage through which a refrigerant flows, the method comprising:
A heat transfer body made of a steel pipe whose interior is filled with a metal material having higher thermal conductivity than the mold material used for the casting is cast in a position that will become part of a heat transfer path from the molding surface to the refrigerant passage. A method of manufacturing a hot press molding die, characterized by embedding the die by embedding the die. Laying a metal plate material for an automobile body part heated to a predetermined temperature on the hot press molding die according to claims 1 to 10 ;
A method for manufacturing an automobile body part, comprising the step of molding the metal plate material by a hot stamping method using the hot press molding die.

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