KR101576645B1 - a method of manufacturing a hot-stamping mold and a hot-stamping mold manufacturing the same method - Google Patents

Abstract

The present invention relates to a hot-stamping mold which forms a heated metal material using a press. According to an embodiment of the present invention, a method of manufacturing a hot-stamping mold comprising an outer core and an inner core inserted into the outer core comprises: a material preparing step of preparing a metal material in a size for forming the outer core and the inner core; a heat treatment step of performing a heat treatment on the metal material to increase hardness of the metal material; a core forming step of forming a cavity unit, whose lower portion is opened in a shape corresponding to a shape to be formed on the outside of the outer core, on the outer core, and forming an insertion unit on the inner core, inserted into the cavity unit and an edge unit protruding from the outside of a lower portion of the insertion unit, wherein a lower surface of the outer core comes into surface contact with an upper surface thereof to be mounted on the upper surface thereof; a welding step of welding around a joining surface while the outer core is mounted on the edge unit to weld the outer core and the inner core; and an outer shape forming step of forming a shape of a product to be shaped on an outer surface of the outer core after the welding step. Therefore, deformation caused by the heat treatment is minimized, and a hot-stamping mold with excellent cooling performance can be manufactured.

Description

A method of manufacturing a hot stamping mold and a hot stamping mold produced by the manufacturing method,

The present invention relates to a hot stamping die for molding a heated metal material by using a press.

Recently, there are many suggestions for minimizing consumption of oil due to high oil prices. In particular, in the case of automobiles that consume a large amount of petroleum, it is a trend to lighten the vehicle in order to cope with high oil prices by improving fuel efficiency.

An example of reducing the weight of a vehicle includes a hot stamping method in which a heated metal material is pressed and molded by a press in order to increase the rigidity of parts of the vehicle and at the same time to lighten the weight.

In this hot stamping molding, a metal material is pressurized in a heated state to form a product, so that the structure becomes dense and a product having high hardness can be molded.

On the other hand, when the hot stamping is performed, since the metal is heated at a temperature of several hundred degrees, the metal mold for molding the product is also heat-transferred to cause thermal deformation, thereby increasing the defect rate of the product.

In order to solve this problem, a "hot stamping molding die" has been disclosed in Korean Registered Patent No. 10-1326824 (published on Nov. 11, 2013).

A conventional hot stamping molding die includes a base plate through which cooling water is supplied and discharged through a nipple mounted on one side; An outer shape block formed in the same shape as the outer shape of the product to form an outer shape of the product during hot stamping molding, at least one of which is mounted on one surface of the base plate, and a mounting space is formed therein; And cooling water introduced through the base plate between the outer block and the outer block is inserted into the mounting space of the outer block, so that cooling water flows into the mounting space of the outer block, And an insert block mounted between the base plate and the outer shape block so as to flow on the outer plate.

In the conventional hot stamping molding die, the cooling water passes through the inside of the die, so that the die is cooled by the cooling water to prevent thermal deformation of the die, thereby minimizing the defect rate of the product.

Meanwhile, in manufacturing a conventional hot stamping mold, heat treatment is performed in a state where the outer shape block and the insert block are welded. Therefore, thermal deformation occurs in the outer shape block and the insert block due to the heat treatment, A space is formed between the outer block and the insert block, and the mold for hot stamping is damaged.

Further, since welding is performed at the lower end portion in a state where the insert block is inserted into the outer shape block, there is a problem that the welded portion is damaged by the pressing force of the press.

In addition, since the passage through which the cooling water passes is performed only by machining, it is difficult to form a complicated flow path and the cooling performance is lowered.

Further, it is difficult to confirm the airtightness of the flow path, which causes a problem that the cooling performance is deteriorated due to uneven distribution of the cooling water.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems as described above, and it is an object of the present invention to minimize the thermal deformation by heat treatment, minimize the defect rate of the product, The present invention provides a method of manufacturing a hot stamping mold and a hot stamping mold capable of minimizing breakage of a welded portion.

A further object of the present invention is to provide a method of manufacturing a hot stamping mold and a hot stamping mold capable of confirming the airtightness of the flow path to prevent deterioration of cooling efficiency due to defective airtightness of the flow path, .

According to another aspect of the present invention, there is provided a method of manufacturing a hot stamping mold including an outer core and an inner core coupled to the outer core, A heat treatment step of heat-treating the metal material so that the hardness of the metal material is increased; a step of forming a groove having a shape corresponding to a shape to be formed on the outer side of the outer core, A core forming step of forming an inner core inserted into the cavity and an outer core protruding outside the lower portion of the insert core and having a bottom surface in contact with the upper surface of the outer core, And welding the periphery of the joint surface in a state where the outer core is seated in the rim portion, Welding step of welding the outer core group, and after the welding step may include an outer shape molded to form the shape of the product to be molded on the outer surface of the outer core.

Wherein the core forming step includes a flow path forming step of forming a flow path through which the cooling water passes on the bottom surface of the cavity, and the airtight groove of the flow path groove is sandwiched between the core forming step and the welding step, And a cohesion confirmation step of confirming the cohesion.

In the flow path forming step, the flow path groove may be primarily machined, and then discharge processing may be performed secondarily.

And forming a hole in the inner core to supply cooling water through the inner core between the material preparing step and the core forming step.

And a welding groove forming step of forming a welding groove for performing welding around the joint surface to perform the welding between the core forming step and the welding step.

And a sealing material processing step of applying a sealing material sealing between the inner core and the outer core between the core forming step and the welding step.

The hot stamping metal mold according to the embodiment of the present invention can be manufactured by the manufacturing method of the hot stamping metal mold according to the embodiment of the present invention described above.

According to the present invention, heat treatment is performed before forming the inner core and the outer core, thereby minimizing the failure of the product due to thermal deformation and the breakage of the inner core and the outer core.

In addition, welding is performed around the outer core and the inner core in the welding step, so that breakage of the welded portion due to the pressing force of the press can be prevented.

Further, the flow grooves through which the cooling water passes can be formed by machining and electric discharge machining, and various types of flow grooves can be formed.

Further, by performing the sealing treatment between the inner core and the outer core in the sealing material processing step, the airtightness of the flow path can be improved.

In addition, it is possible to check the airtightness of the flow path in the coalescing confirmation step, thereby preventing the deterioration of the cooling performance due to the poor airtightness of the flow path.

1 is a flowchart schematically showing a method of manufacturing a hot stamping mold according to an embodiment of the present invention.
2 is a perspective view illustrating a hot stamping mold manufactured by the method of manufacturing a hot stamping mold according to an embodiment of the present invention.
3 is an exploded perspective view illustrating a hot stamping mold according to an exemplary embodiment of the present invention.
4 is a bottom view of an outer core constituting a hot stamping mold manufactured by a method of manufacturing a hot stamping mold according to an embodiment of the present invention.
5 is a cross-sectional view taken along line AA of FIG.
6 is a cross-sectional view taken along the line BB in Fig.
7 is a cross-sectional view illustrating a state in which a sealing material is installed in a hot stamping mold manufactured by the method of manufacturing a hot stamping mold according to an embodiment of the present invention.
FIG. 8 is a cross-sectional view illustrating a configuration of a flow path when a hot stamping mold manufactured by the method of manufacturing a hot stamping mold according to an embodiment of the present invention includes a base plate.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

First, the hot stamping molding refers to a molding in which an upper mold and a lower mold, which are interlocked with each other with a heated base material interposed therebetween, are pressed by a press to produce a product. In the hot stamping mold 100 according to the embodiment of the present invention, One or both of the upper mold and the lower mold may be manufactured.

As shown in FIGS. 2 to 8, the hot stamping mold 100 manufactured by the manufacturing method of the hot stamping mold 100 according to the embodiment of the present invention is located outside And an inner core 130 inserted into the outer core 110 and hermetically sealing the flow grooves 113 are welded to each other.

The outer core 110 and the inner core 130 may be made of a different metal material.

For example, since the outer core 110 directly molded the product, the inner core 130 uses a dense material and the outer core 110 supports the outer core 110, The tissue can be made using less dense materials.

As shown in FIGS. 1 to 8, the manufacturing method of the hot stamping mold 100 according to the embodiment of the present invention may include a material preparing step (S10).

In the material forming step S10, a metal material for forming the outer core 110 and the inner core 130 may be formed to have a size to form the outer core 110 and the inner core 130.

At this time, the metal material may be formed by cutting a large metal material into a block shape, or by casting a metallic material into a block shape to form the outer core 110 and the inner core 130 in advance.

In the material preparing step (S10), the prepared metal material can be ground.

The sanding is carried out in such a manner that each surface is shaved so as to form a uniform plane so as to facilitate the processing of the prepared metal material. The outer core 110 and the inner core 130 may be formed to have a size larger by about 1 mm to 2 mm than the outer core 110 to be formed in consideration of the deformation after the heat treatment.

The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include a touching step S20.

The touching step S20 may perform touching on the metal material provided in the material preparing step S10.

The touching process is carried out by forming a hole (not shown) in the outer core 110 or the inner core 130 so as to form the supply holes 115 and 135 and the discharge holes 117 and 137 for supplying and discharging the cooling water to and from the channel groove 113 to be formed in the outer core 110, Which means machining.

For example, as shown in FIG. 6, when the cooling water is supplied through the outer core 110, the outer surface of the outer core 110 is connected to the flow path groove 113 formed in the outer core 110, The inner core 130 may be formed in advance so as to communicate with the flow path groove 113 so as to supply cooling water to the flow path groove 113 to be formed in the outer core 110 through the inner core 130, It can be formed in advance on the bottom of the frame.

Here, the touching step S20 may be performed after the core forming step S40, which will be described later. However, the touching step S20 may be performed before the shape of the outer core 110 and the inner core 130 is formed, The shape of the outer core 110 and the inner core 130 can be more easily formed because the metal material is partially removed in the touching step S20 so that the touching step S20 is performed in the core forming step S40 ). ≪ / RTI >

The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include a heat treatment step S30.

In the heat treatment step S30, the heat treatment may be performed so that the hardness of the metal material subjected to the touch operation is increased.

Meanwhile, in the heat treatment step S30, the outer core 110 and the inner core 130 are heat-treated by heating the metallic material into a heating furnace. At this time, Depending on the material or size of the metal material to be formed on the substrate 130, it is preferable that the heat treatment is performed at a temperature of about 800 to 1000 degrees.

When the outer core 110 and the inner core 130 are subjected to the heat treatment before the forming, thermal deformation occurs in the outer core 110 and the inner core 130, The airtightness of the flow path to be described below is lowered to prevent the cooling performance from deteriorating.

 The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include a core forming step S40.

In the core forming step S40, the heat treated metal material may be processed to shape the outer core 110 and the inner core 130. [

Meanwhile, the core forming step S40 may form the outer core 110 and the inner core 130 so that the outer core 110 and the inner core 130 are coupled to each other to form a flow path.

In the core forming step S40, except for the outer surface of the outer core 110, that is, the outer surface of the outer core 110, the outer core 110 and the inner core 130 ) Is formed by machining to form a shape.

At this time, in the core forming step S40, the outer core 110 and the inner core 130 are combined to perform finishing within an error range of 0.03 mm to 0.05 mm to ensure airtightness of the flow path.

Meanwhile, in the core forming step S40, the outer core 110 may be formed with a hollow portion 111 having a bottom open so that a part of the inner core 130 can be inserted.

The cavity portion 111 may have a shape corresponding to the outer surface to be formed in the shape of the product to be molded, and may have a uniform thickness with the outer surface to be formed with the inner surface of the cavity portion 111.

In addition, the core forming step S40 may include a flow path forming step S41.

The flow path groove forming step S41 is a step of forming a flow path between the inner core 130 and the outer core 110 in such a manner that the cooling water passes through the inner surface of the cavity core 111 of the outer core 110, (113) can be formed.

On the other hand, the flow grooves 113 are formed by machining such as a lathe, milling, CNC or the like. When there is a portion where the depth of the cavity portion 111 is deep and machining is difficult, The flow grooves 113 can be formed in such a manner that the discharge grooves are formed and the discharge jig is secondarily formed and discharge processing is performed through the discharge jig.

Here, since the electric discharge machining is a known technique, detailed description is omitted.

The channel grooves 113 may be formed along the longitudinal direction so that the cooling water passes through the longitudinal direction of the product to be formed Of the outer core 110 in contact with the outer core 110.

In this way, when the flow path groove 113 is formed in the longitudinal direction, the cooling water can be rapidly circulated and the cooling performance can be improved because the flow path can be easily formed without being complicated in the linear direction unlike the conventional case.

In the core forming step S40, the inner core 130 can be formed.

The inner core 130 is formed with an insertion portion 131 in a shape corresponding to the cavity 111 except for the flow path groove 113 so that the cooling water flowing through the flow path groove 113 does not flow. And a rim 133 protruding outwardly from the lower end of the outer core 110, and the bottom surface of the outer core 110 is in surface contact with the upper surface.

The outer core 110 and the inner core 130 thus formed are inserted into the hollow portion 111 of the outer core 110 of the inner core 130 and inserted into the open lower portion of the flow path groove 113 And the lower end portion of the outer core 110 is coupled with the inner core 130 so as to be in surface contact with the upper surface of the rim portion 133 of the inner core 130. [

The core forming step S40 may include a welding groove forming step S42.

The welding groove forming step S42 is a step of welding the outer circumferential surface of the formed outer core 110 and the inner core 130 to the circumference of the joining surface on which the rim 133 and the outer core 110 are mounted The welding groove 150 can be formed.

At this time, the welding groove 150 may be formed along the circumference of the joint surface in a "C" shape, and the flux may be seated in the welding groove 150 to firmly couple the two.

The manufacturing method of the hot stamping mold 100 according to the embodiment of the present invention may include a sealing material processing step (S50) (see FIG. 7).

The sealing material processing step S50 may process the sealing material 190 to more reliably perform airtightness in the state where the outer core 110 and the inner core 130 are coupled.

The sealing member 190 may be applied to the inner surface of the cavity 111 of the outer core 110 or the outer surface of the insertion portion 131 of the inner core 130 or may be applied to the outer core 110 and the inner core 130 of the first embodiment.

Here, the sealing material 190 may be silicon, urethane, natural rubber, synthetic rubber, synthetic resin, oil, grease, or a metal material having airtightness.

 The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include a step of confirming cohesion (S60).

The cohesion confirmation step S60 is a step of inserting the insertion portion 131 of the inner core 130 into the cavity portion 111 of the outer core 110 and sealing the flow path groove 113 Confidentiality status can be confirmed.

The adhesion confirmation step S60 is a step of coating the outer surface of the insertion portion 131 of the inner core 130 or the inner surface of the cavity portion 111 of the outer core 110 and inserting the insertion portion 131 into the cavity portion 111, it is possible to confirm the airtightness of the flow path in such a manner as to grasp whether or not the flow path groove 113 is exactly caught on the outer surface of the insertion portion 131.

If the portion where the flow path is not airtight is generated in the cohesion checking step S60, the portion may be reprocessed to modify the hot stamping mold 100, or the inner core 130 or the outer core 110, .

As described above, in the cohesion confirmation step (S60), the airtightness of the oil passage can be checked to prevent the deterioration of the cooling performance due to the oil passage failure.

The manufacturing method of the hot stamping mold 100 according to the embodiment of the present invention may include a welding step S70.

In this welding step S70, the insertion portion 131 of the inner core 130 is inserted into the cavity 111 of the outer core 110, and the bottom of the outer core 110 is inserted into the rim of the inner core 130 The outer core 110 and the inner core 130 may be joined to each other in a state of being welded along the side surfaces overlapped with each other while being seated on the upper surface of the inner core 133.

At this time, the welding is performed in the welding groove 150, and the welding groove 150 may be filled with a flux for welding the inner core 130 and the outer core 110.

The pressing force of the press transmitted to the outer core 110 is transmitted to the inner core 130 by welding the edge portion 133 of the inner core 130 contacting with each other and the lower end of the outer core 110 It is possible to prevent cracks from being generated in the welded portion.

Here, when the outer core 110 and the inner core 130 are made of different materials, they can be welded using different kinds of welding methods.

The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include an outer shape molding step S80.

This outline molding step S80 forms the outer surface of the outer core 110 in the shape of the product to be molded.

At this time, the outer surface of the outer core 110 is machined by machining to cut the outer core 110.

When the plurality of hot stamping dies 100 are assembled to form one product in the outline forming step S80, the hot stamping dies 100 are assembled together after the final assembly, In the outer shaping step (S80), the outer shape can be formed by rough roughing the surface to smoothly process.

Here, when the hot stamping mold 100 is not divided into a plurality of hot stamping dies 100, it is natural that the finishing is performed so that the surface is smoothed in the outer shape molding step S80.

If the hot stamping mold 100 is integrally manufactured, it is completed in the outer shape molding step S80. However, when the hot stamping mold 100 is divided into a plurality of pieces, .

The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention may include an assembling step S90.

In the assembly step S90, when the mold is divided into a plurality of hot stamping dies 100 to produce a single product, the plurality of hot stamping dies 100 may be assembled into one unit.

Meanwhile, in the assembling step S90, a plurality of hot stamping dies 100 are assembled before finishing to smooth the surface of the facing surface during assembly, and the finned dies are coupled to the base plate 170 (Refer to FIG. 8, reference numeral 175 denotes a cooling water supply port formed in the base plate 170, and reference numeral 177 denotes a cooling water discharge port formed in the base plate 170. In FIG. 8, A state in which the integrated hot stamping mold 100 is coupled to the base plate 170 is shown).

The assembling step S90 may include an assembling finishing step S91.

The assembling finishing step S91 may perform finishing to smooth the outer surface of the outer core 110 to perform jointing or molding of the molds assembled to the base plate 170.

By performing finishing after assembling as described above, it is possible to produce a product having a seamless and smooth surface, so that the defective rate of products can be minimized.

After the assembling finishing step S91, assembly and measurement of the machining state of all parts of the mold are performed using a three-dimensional measuring machine, and the defective parts are reprocessed or reworked, so that the hot stamping mold 100 The production can be completed.

The method of manufacturing the hot stamping mold 100 according to the embodiment of the present invention is a method of manufacturing the inner core 130 and the outer core 110 before the outer core 110 and the outer core 110 are heat- The inner core 130 and the outer core 110 are manufactured and then subjected to heat treatment to minimize the occurrence of defects in the hot stamping mold 100 due to thermal deformation.

In addition, by performing welding around the outer core 110 and the inner core 130 in the welding step S70, it is possible to prevent the welded portion from being damaged by the pressing force of the press.

Further, the confidential state of the flow path can be confirmed and corrected in advance through the coarse confirmation step (S60).

In addition, the heat treatment may be performed before the outline forming step (S80) to minimize the deformation of the outer shape due to the heat treatment.

In addition, the channel grooves 113 can be formed by various machining and discharging processes at the same time.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And all changes and modifications to the scope of the invention.

100: Hot Stamping Mold with improved cooling performance 110: Outer core
111: cavity portion 113: flow groove
115, 135, 175: Supply ports 117, 137, 177:
130: Inner core 131: Insertion part
133: rim portion 150: welding groove
170: Base plate 190: Sealing material

Claims (7)

A method of manufacturing a hot stamping mold including an outer core and an inner core coupled to the outer core,
A step of preparing a metal material having a size to form the outer core and the inner core,
A heat treatment step of heat-treating the prepared metal material so as to have a high hardness,
And a bottom portion of the outer core is protruded to the outside of the lower portion of the insertion portion, so that the bottom portion of the outer core is inserted into the bottom portion of the outer core, A core forming step of forming a rim portion that is in surface contact with the upper surface and is seated on the inner core,
A welding step of welding the outer core and the inner core by welding around the joint surface in a state where the outer core is seated in the rim portion;
And an outer shape forming step of forming a shape of a product to be molded on an outer surface of the outer core after the welding step,
Wherein the core forming step includes a flow path forming step of forming a flow path through which the cooling water passes on the bottom surface of the cavity,
Further comprising the step of confirming the airtightness of the flow path groove by inserting the insertion portion into the cavity portion between the core forming step and the welding step,
Characterized in that the cohesion checking step confirms cohesion in a state in which the paint is applied to one of the cavity portion and the insert portion and the other portion is sandwiched by the insert portion in the cavity portion Method of manufacturing a stamping mold. delete The method according to claim 1,
The flow channel forming step
Wherein the flow grooves are primarily machined, and then electrical discharge machining is performed secondarily. The method according to claim 1,
Between the material preparing step and the core forming step
And forming a hole in the inner core to supply cooling water through the inner core. ≪ RTI ID = 0.0 > 21. < / RTI > The method according to claim 1,
Between the core forming step and the welding step
And forming a welding groove for performing welding around the joint surface to perform the welding. The method according to claim 1,
Between the core forming step and the welding step
Further comprising a sealing material processing step of applying a sealing material that hermetically seals between the inner core and the outer core. delete

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