KR101403294B1

KR101403294B1 - Hot stamping appratus with a pressure part and hot stamping method using the same

Info

Publication number: KR101403294B1
Application number: KR1020140022170A
Authority: KR
Inventors: 이수용
Original assignee: 우신정공 주식회사
Priority date: 2014-02-25
Filing date: 2014-02-25
Publication date: 2014-06-03
Also published as: WO2015130078A1

Abstract

The present invention relates to a hot stamping forming apparatus having a pressing unit and a forming method using the same, and an object of the present invention is to provide a pressing unit for pressing and supporting a work between a row pad and a lower plate of a lower die, And a pressing part capable of supporting and pressurizing the material by the pressing part to the upper mold and the lower mold to increase the heat conduction efficiency, and a molding method using the same.
The present invention relates to a hot stamping process for molding a material into a molding by a lower mold which is driven by a press machine and has a cooling line therein and a lower mold provided on the lower plate to correspond to the upper mold, An apparatus comprising:
The lower die includes a row pad contacting a workpiece to form a workpiece and having a cooling line therein, a first row die on which the row pad is seated and supported, and a second row die fixed to the lower plate so as to be positioned below the first row die. And a pressing portion which is installed to be positioned between the first row die and the second row die and presses the one side of the row pad in the supporting and upward direction, So that the cooling efficiency can be increased.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hot stamping apparatus having a pressing part and a molding method using the hot stamping apparatus,

The present invention relates to a hot stamping molding apparatus having a pressing portion and a molding method using the same, wherein a lower portion of the hot stamping molding apparatus is provided with a pressing portion, and when the hot stamping press molding is performed, The present invention relates to a hot stamping molding apparatus and a molding method using the hot stamping molding apparatus. The hot stamping molding apparatus includes a pressing portion that supports and pressurizes the material to increase the heat transfer efficiency of the material by closely contacting the upper and lower molds.

Generally, a method of manufacturing a molded article by heating a boron steel material to a temperature above the Ac3 temperature and then quenching rapidly inside the closed mold immediately after the high-temperature molding is referred to as a hot pressing method, and this method is called a hot stamping method. It is also called a press hardening method because a high strength martensite structure appears on the steel sheet.

In such a hot stamping method, a boron steel material having improved hardenability by adding B, Mo, Cr or the like is heated to a high temperature of 900 ° C or higher, which is the Ac3 transformation point or more, to be fully austenitized. Is a method for producing a high strength product by martensitization through rapid cooling while hot forming in the shape of a product. This method is widely used for manufacturing a high strength automotive body component having a tensile strength of 1470 MPa.

In the press hardening process using the hot stamping method, the wound steel plate coil C is cut to a predetermined size by a cutting equipment, and the cut plate material is charged into a heating equipment such as an oven or a furnace The plate material is heated to a temperature equal to or higher than the Ac3 transformation point so that the plate material of the steel material is completely austenite and then the plate material is directly transferred to the press mold to be molded by stamping, And is transformed into high strength martensite by quenching using a cooling system in a state where it is under pressure.

In this case, the steel sheet is supplied in a sheet form in a state of being blanked in advance, and is put into a box furnace and heated. After reaching the target temperature, the steel sheet is held for about 5 minutes, A pre-process that is rapidly introduced into the apparatus, a post-process such as trimming and piercing, and a main process for press-molding and cooling the mold.

Since the steel sheet produced by such a hot stamping process has a high tensile strength of 1500 MPa or more as having a martensite structure, the vehicle body can be formed with a thin thickness, so that the vehicle body is made lightweight and molded under high temperature conditions As a result, the springback phenomenon can be prevented and the dimensional accuracy can be improved. As a result, the moldability can be improved, It can be applied to parts requiring ultra-high strength which is difficult to be molded due to a lack of post-shape deformation (springback), and contributes greatly to weight reduction of automobiles.

A conventional hot press forming apparatus is configured to place a heated to-be-molded object between upper and lower molds provided with a molding region having a shape to be molded and to perform molding by applying a mechanical force. In order to perform cooling of the object immediately after the molding is performed by pressurization of the mold, a cooling passage through which the coolant flows is provided inside the mold.

The conventional hot press forming apparatus thus constructed is an indirect cooling method in which cooling is performed by contact between the upper and lower molds in which cooling passages are formed and the material to be molded. The contact surfaces of the upper and lower molds, Efficient cooling can be performed, and control of the cooling temperature over the entire area of the molding can be achieved.

However, since the conventional hot press forming apparatus is formed by pressing the press apparatus connected to the upper mold, the area (gap) where the contact between the mold and the object is not smooth due to the thickness of the material and the coupling of the mold itself, When the gap is generated, the material is not uniformly cooled and the physical properties of the entire region of the material to be molded are different. Therefore, it is difficult to produce a product having a uniform strength or a desired strength There was a problem.

In order to solve such a problem, it is necessary to design the mold so that the contact is accurately performed. However, even if the mold is manufactured in such a manner that the mold itself is difficult to manufacture and the contact is accurately made, There is a problem that it is practically difficult to uniformly produce the physical properties of the object to be molded.

There is also a method in which the pressure between the mold and the molding is controlled in the press apparatus so that there is no gap between the mold and the molding. However, the domestic hot press is subjected to the hot press using the cooling press system, In order to control the pressure in the press apparatus, the entire mold and the structure of the apparatus have to be changed.

Patent Registration No. 10-0951042 (Mar. 26, 2010) Patent Registration No. 10-1225433 (2013.01.16) Published Patent Publication No. 10-2011-0081706 (July 14, 2011) Published Patent Publication No. 10-2013-0015633 (Feb.

An object of the present invention is to provide a pressing part for pressing and supporting a work between a row pad and a lower plate of a lower mold and to support and press-contact the work with an upper mold and a lower mold by a pressing part during press- And a molding method using the hot stamping molding apparatus.

The present invention relates to a hot stamping process for molding a material into a molding by a lower mold which is driven by a press machine and has a cooling line therein and a lower mold provided on the lower plate to correspond to the upper mold, An apparatus comprising:

The lower die includes a row pad contacting a workpiece to form a workpiece and having a cooling line therein, a first row die on which the row pad is seated and supported, and a second row die fixed to the lower plate so as to be positioned below the first row die. And a pressing portion which is installed to be positioned between the first row die and the second row die and presses the one side of the row pad in the supporting and upward direction, So that the cooling efficiency can be increased.

In the present invention, the pressing portion is provided at the lower portion of the lower pad of the lower die, and the material is brought into close contact with the upper pad by the pressing portion during the molding process, so that the heat transfer rate is improved. The cooling efficiency with respect to the heated material is improved, and a molded product having high strength and uniform quality of physical properties can be secured.

The present invention improves the heat transfer efficiency for the material, thereby shortening the molding cycle time, thereby improving the overall productivity. For example, when molding is performed using an 800 ton press apparatus (press force of about 750 tons), a cycle time of about 35 to 40 seconds is conventionally formed for a single molded product, Cycle time is provided, so that the molding cycle time is reduced to almost half.

The present invention has a simple structure in which a pressurizing portion is provided below a row pad of a lower mold, so that it can be easily applied to a conventional hot press forming apparatus without changing the entire mold structure and equipment structure, And the manufacturing cost can be reduced, and there is a great ripple effect on the industrial field in this technical field.

The present invention is characterized in that the pressurizing portion is divided into a first pressurizing portion having a long stroke and a second pressurizing portion having a short stroke with a stroke relatively short as compared with the first pressurizing portion and the first pressurizing portion The lower center pad is supported (pressed), and the first pressurizing portion and the second pressurizing portion support (press) the lower center pad with respect to the secondary pressurizing portion. Thus, while the lowering speed of the upper mold by pressing is maximized, The upper mold and the lower mold are brought into complete contact with each other, thereby reducing the loss time during mass production and increasing the mass production rate.

In the present invention, the cooling water supply line of the press hardening metal mold is made straight, so that the cooling line located inside the metal mold can be simplified, and uniform cooling, that is, a cooling rectangular area generated in the conventional cooling line is not generated It is possible to uniformly cool the material, thereby improving the overall cooling efficiency and improving the physical properties of the molding.

Since the cooling line can be straightened and simplified, the present invention can easily meet the required molding load due to the structural problem of the mold, and can easily design and manufacture the mold.

According to the present invention, in the case of a two-cavity structure having two molding spaces, a reinforcement pressing portion is further provided between one lower mold and a lower plate among two lower molds, so that the thickness error of the material In the case where the cooling of one of the moldings can not be performed uniformly due to the generated error, the cooling of the molding in the two-cavity is uniformly performed by the correction of the pressing force by the reinforcing and pressing portion.

1 is an illustration showing a configuration according to the present invention;
Fig. 2 is an exemplary view showing the constitution of a molded article according to the present invention
FIG. 3 is a view showing an example of a configuration of a graphic form according to the present invention
Fig. 4 is an exemplary view showing the configuration of a lower mold according to the present invention
Fig. 5 is another example showing the configuration of the lower mold according to the present invention
6 is a view showing an example of a configuration of a row center pad according to the present invention.
Fig. 7 is an exemplary view showing a configuration of a cooling line according to the present invention
FIG. 8 is an exemplary view showing a configuration of a conventional cooling line
9 is an exemplary view showing an assembled state of the pressing portion according to the present invention
10 is an exemplary view showing a configuration of a pressing portion according to the present invention
11 is an exemplary diagram showing an operating state according to the present invention (falling period)
12 is an exemplary view showing an operating state according to the present invention (first pressing section)
FIG. 13 is an exemplary view showing an operating state according to the present invention (second pressure section)
FIG. 14 is an exemplary view showing a configuration in which the correction pressure section according to the present invention is installed
15 is a graph showing the results according to the embodiment of the present invention

Fig. 1 is an exemplary view showing the constitution according to the present invention, Fig. 2 is an illustration showing the constitution of a molded article according to the present invention, Fig. 3 is an example showing a configuration of a top mold according to the present invention, 6 is a view showing a configuration of a row center pad according to the present invention, and FIG. 7 is a view showing an example of a configuration of a lower center pad according to the present invention. Fig. 9 is a view showing the structure of the cooling line according to the present invention, Fig. 8 is an illustration showing the structure of the conventional cooling line, Fig. 9 is an example showing the assembled state of the pressing portion according to the present invention, Fig. 11 is an exemplary view (descending section) showing an operating state according to the present invention, Fig. 12 is an exemplary view showing an operating state according to the present invention (first pressing section), and Fig. Fig. 13 is an exemplary view showing the operating state according to the present invention (second pressurizing section) , That Fig. 14 is an exemplary view showing the pressure correcting portion installed configuration in accordance with the invention, Figure 15 shows a graph illustrating the effects of the present invention embodiment,

The present invention relates to a lower mold (100) mounted on a lower plate (700) to correspond to the upper mold (200) and having a cooling line therein, a top mold (200) driven by a press machine and having a cooling line therein, 1. A hot stamping molding apparatus (500) for molding a material (300) into a molding (310)

The lower mold 100 includes a row pad 130 which is in contact with a work 300 to form a work 300 and has cooling lines 160 and 170 therein, A first row die 110 and a second row die 120 fixed to the lower plate 700 to be positioned below the first row die 110; And a pressing portion 180 installed between the dies 120 and pressing and supporting one side of the row pad 130 in the upper and upper direction,

The material 300 is closely contacted with the upper mold 200 and the lower mold 100 by the pressing portion 180 during the hot forming of the material so that the cooling efficiency is increased.

As shown in FIG. 2, the molded product 310 includes a predetermined bent portion 311, a bent portion 311, and a bent portion 311. The bent portion 311 has a cross- A sidewall 312 positioned at both sides of the sidewall 312 and a flange 313 located at an end of the sidewall 312 and having a hat shape. Such a molded article is a known molded article widely applied to automobile-related parts or ship-related parts such as a center pillar, a front pillar, a rear pillar, a bumper and the like of an automobile, and a detailed description thereof will be omitted. The molding 310 shown in the drawings of the present invention is shown by way of example of a center pillar of an automobile.

3, the upper die 200 includes an upper die 210 connected to the press 500 and a lower plate 130 connected to the upper die 210. The lower die 130 is coupled to the upper die 200, And an upper pad 230 for molding the material 300 into a molded product 310. The upper pad 230 includes an upper steel part 210 supported by a plurality of upper gas springs 220 240 are inserted into the upper molding groove 243 fixed to the upper die 210 and passed through the upper steel part 240 to form the curved part 311 and the side wall part 312 of the molded product 310 And an upper center pad 250.

The upper steel part 240 includes an upper steel plate 241 supported by the upper gas spring 220 of the upper die 210 and a flange part 321 fixed to the upper steel plate 241, And an upper steel 242 for molding the steel sheet.

The upper center pad 250 and the upper steel 242 directly contact the workpiece to form a workpiece. Cooling lines 260 and 270 are installed inside the upper center pad 250 and the upper steel bar 242, A gas spring stopper 221 fixed to the plate 241 is provided. That is, the upper steel part 240 is supported and connected by the upper gas spring 220 by the gas spring stopper 221. Reference numeral 280 is a phase guide.

4 to 6, the row pad 130 includes a low steel part 140 fixed to the first row die 110 and having a lower forming groove 143, And a low center pad 150 installed vertically movably on the die 110 and inserted into the lower forming groove 143 of the low steel part 140 to form the bent part 311 of the molded product.

As shown in FIGS. 4 to 6, the low steel part 140 includes a low body plate 141 fixed to the first low die 110, And a low steel 142 for forming the flange portion 313 and the side wall portion 312 of the flange portion 313.

The lower body plate 141 is provided with a plurality of low gas springs 144 corresponding to the upper gas springs 220. That is, when the lower gas spring 144 is lowered, the gas spring stopper 221 of the upper gas spring 220 is held in contact with the lower gas spring 144. The lower gas spring 144 is a gas spring, And a color gas spring whose timing is adjusted.

4 to 7, the low center pad 150 is divided into a plurality of portions around a curved portion 314 (a curved vertex of the curved portion of the molded product) of the curved portion 311 of the molded product. That is, when the curved portion 314 of the curved portion is one, the low center pad 150 is divided into two, and when the curved portions 314 of the curved portion are two, the low center pad 150 is divided into three . The low center pad 150 shown in the present invention is an example of a molding having a single curved portion 314 as an automobile center filler shown in FIG. 2 (b) Are separated into two parts.

Each of the low center pads 150 separated by one or a plurality of the plurality of lower center pads 150 includes a row pad steel 151 that contacts the work 300 when the upper die 200 is lowered by a pressing force, And a lower pad body 152 connected to a lower portion of the lower pad steel 151 to support the lower pad steel 151.

6, a key 154 protrudes from the bottom of the lower pad steel 151 and a key groove 155 into which the key 154 is inserted is formed in the lower pad body 152 So that the low pad steel 151 and the low pad body 152 can be integrated by key / key groove connection and bolt connection.

A guide post 153 penetrating the first and second row dies 110 and 120 and the pressing portion 180 is disposed under the row pad body 152. The guide post 153 is press- Thereby guiding the lower center pad 150 to descend.

In addition, cooling lines 160 and 170 are installed inside the low pad steel 151 and the low steel 142.

The upper center pad 250, the upper steel 242, the lower pad steel 151, and the lower steel 142 having the cooling lines 160, 170, 260 and 270, respectively, And the plurality of steel blocks SB are connected to each other by connection bolts CB to form cooling lines 160, 170, 260, and 270, respectively. At this time, an O-ring (R) is installed between the cooling line of the one-side steel block and the cooling line of another steel block in contact with the cooling line. That is, the cooling lines 160, 170, 260, and 270 are connected to each other to maintain watertightness by the coupling force of the O-ring R and the connection bolt CB. The cooling lines 160, And the low-steel steel 151 and the low steel 142, respectively, so that the uncooled zone generated in the conventional cooling line is not generated, and the value of the cooling fluid flow resistance is minimized.

The upper center pad 250, the upper steel 242, the lower pad steel 151 and the lower steel 142 are assembled in the same manner as the cooling lines 160, 170, 260 and 270. Therefore, The connection relationship of the lines 160, 170, 260 and 270 will be described with reference to FIG.

7A shows a simplified assembling relationship. The upper center pad 250, the upper steel 242, the lower pad steel 151, and the lower steel 142 have the first, second, third, The first and second steel blocks b1 and b2 are bolted to the steel block b2 and the third steel block b3 is bolted to the steel block b2, The third steel block b3 is bolted to the third steel block b3, and the first, second, third and fourth steel blocks are integrated.

In this case, an O-ring r1 is provided between the first and second cooling lines w1 and w2 of the first and second steel blocks b1 and b2, An o-ring r2 is installed between the second and third cooling lines w2 and w3 and an o-ring r3 is provided between the third and fourth cooling lines w3 and w4 of the third and fourth steel blocks b3 and b4. The first, second, third and fourth cooling lines w1, w2, w3 and w4, that is, the cooling lines 160, 170, 260 and 270, are linearly connected by o-rings r1, r2 and r3.

The first, second, third, and fourth steel blocks may have a key (k1) protruded therefrom, and the first, second, third, and fourth steel blocks may be mounted on the body (low body plate, The upper steel plate, and the upper die) is formed with a key groove k2, and the first, second, third and fourth steel blocks and the body are bolted together.

7B shows the cooling lines 160 and 170 positioned in the low pad steel 151 and the low steel 142. The cooling lines 160 and 170 are disposed at one end of the low pad steel 151 and the low steel 142, It can be seen that the cooling lines 160 and 170 are positioned in a straight line.

That is, as shown in FIG. 8, the cooling line 900 of a conventional mold die having a plurality of steel blocks is formed by connecting the cooling line from the mold steel 910 to the mold plate 920 by a plurality of bending Cooling zone 930 and cooling resistance zone 940. In contrast to the present invention, the cooling lines 160, 170, 260 and 270 are connected in a straight line, do.

4 to 6, the first low die 110 includes a lower steel part 140 fixed to the upper surface 111 and a lower steel pad 140 fixed to the lower surface of the lower center pad 150, The first pressing part 110 is formed to have a predetermined depth from the upper surface 111 and the lower surface 113 communicating with the seating hole 112, And the hole 114 is formed to have a predetermined depth. At this time, the seating hole 112 and the first pressure hole 114 are formed in the first row die 110 so as to be in communication with each other.

Further, a plurality of sliding blocks 115 for guiding the movement of the low center pad 150 are further installed around the seating hole 112.

4 to 6, the second row die 120 is formed with a second pressing hole 122 through which one side of the pressing portion 180 is inserted and supported on the upper surface 121, A second post hole 123 through which a guide post 153 connected to the low center pad 150 is inserted and an installation hole 124 in which one side of the pressing portion is installed are formed in the second pressure hole 122 . Also, the first row die 110 and the second row die 120 are bolted to each other.

The pressurizing unit 180 pressurizes the material in the upper mold direction when the material is formed to closely contact the upper mold and the lower mold to improve uniform cooling and cooling efficiency. FIGS. 4 to 6, 9 and 10 As shown in the figure, the pressing unit 180 primarily presses (pressurizes) the row pad 130 with respect to the primary pressing region P1 according to the pressing force of the upper mold 200, And the lower pad 130 is secondarily supported with respect to the secondary pressing section P2 according to the upper pressing force so that the blank 300 is moved to the upper mold 200 And a second pressing portion 182 which is in close contact with the lower mold 100,

The second pressing portion 182 is installed to be positioned between the first row die 110 and the second row die 120 and the first pressing portion 181 is disposed between the second pressing portion 182 and the first row And is installed on the second row die 120 so that the upper end thereof is contactably supported on the row pad 130 through the die 110.

The first pressing portion 181 firstly supports the row pad 130 with respect to the first pressing portion according to the upper pressing force so as to bring the blank 300 into close contact with the upper mold 200 and the lower mold 100, The upper end of the lower die 130 is fixed to one side of the row pad 130, that is, the lower center pad 150 and the lower end thereof is fixed to the mounting hole 124 formed in the second pressure hole 122 of the second row die 120 So as to penetrate through the second pressing portion 182 and the first row die 110.

The pressing force is set in consideration of the lowering speed of the upper mold 200 by the pressing in the primary pressing section P1 and the increase of the adhesion between the lower center pad 150 and the work 300 in the first pressing section 181. [ do. That is, the first pressing portion 181 is provided so as to have a pressing load of 0.05P to 0.3P with respect to the molding load P transmitted to the upper mold by the press. The setting of the pressing load of the first pressing portion 181 and the operation of the first pressing portion 181 in the primary pressing section P1 directly affect the molding cycle time so that the setting range of the pressing load is It is a very important factor.

That is, when the pressing load of the first pressing portion 181 is less than 0.05P, it is difficult to maintain the balance of the low center pad while maintaining the balance, and when the pressing load exceeds 0.3P, the lowering speed of the top- Or the lowering operation is not properly performed, and the loss rate is reduced due to an increase in the loss time.

The first pressing portion 181 may be formed of a plurality of gas springs, a hydraulic spring, or a disk spring so as to stably support (press) the low center pad 150. [ That is, the low center pad 150 is supported by a plurality of gas springs, and the low center pad 150 is supported by two or three or four points by a gas spring.

The second pressing portion 182 secondarily supports (pressurizes) the row pad 130 in the second pressing region P2 according to the upper pressing force to press the blank 300 in the upper and lower molds 200 and 100, Thereby improving the cooling efficiency of the material.

The second pressing portion 182 includes a first spring plate 183 inserted into the first row die 110, a second spring plate 184 inserted into the second row die 120, A plurality of second pressing springs 185 installed between the two spring plates 183 and 184 for elastically supporting the first spring plate 183 and a plurality of second pressing springs 185 passing through the first spring plate 183, And a plurality of retainers 186 bolted to the first spring plate 184 to limit the movement range of the first spring plate 183 by the second biasing spring 185.

The second pressing portion 182 may be formed of a plurality of gas springs, a hydraulic spring, or a disk spring, and preferably a gas spring or a disk spring.

As described above, the pressing portion 180 composed of the first pressing portion 181 and the second pressing portion 182 has a pressing force smaller than the molding load P of the upper mold. That is, the first pressing portion 181 is formed so as to have a pressing force of 0.05P to 0.3P with respect to the molding load P transmitted to the upper mold by the press, and the pressing force sum of the first and second pressing portions 181, Is smaller than the molding load (P).

In order to explain the molding process according to the present invention, the primary pressurizing section P1 and the secondary pressurizing section P2 are separated from each other by operating sections of the mold during the yearly molding,

11 to 13, the upper mold 200 is lowered in the direction of the lower mold 100 by the press to move the upper mold 242 and the upper mold 242 300, a predetermined gap G is maintained between the top center pad 250 and the upper center pad 250,

A primary pressurizing section P1 for holding the upper center pad 250 of the upper mold and press forming the material 200 while the predetermined gap G is maintained between the upper steel 242 of the upper mold and the material 300, ,

The upper mold 200 is pressurized and lowered so that there is no gap G between the upper steel 242 of the lower mold and the material 300 placed on the lower steel 142 of the lower mold, And is separated into a secondary pressurizing zone P2 for cooling the formed product 310 by cooling.

The predetermined gap G prevents clearance between the upper and lower molds during molding and prevents scratches due to friction and clearance for a smooth molding process. When the material thickness is about 1.2 to 1.5 mm, 2 to 10 mm, preferably about 2 to 6 mm, and more preferably about 5 to 6 mm.

Such a gap is used for deep drawing (deep drawing), so a detailed description thereof will be omitted. In addition, the material 300 is placed on the lower pad 130 of the lower mold during molding.

The first spring plate 183 is installed to be inserted into the first pressure hole 114 of the first row die as shown in FIGS. 4, 5 and 10, and when the upper mold 200 is press- A plurality of retainers 186 are inserted and penetrated by being supported by lower portions of the row center pads 150, that is, the lower pad bodies 152 of the row center pads 150 inserted into the seating holes 112 of the first row die A plurality of first through holes 183c through which the first pressing portion 181 penetrates are formed in the first through hole 183a and the spring mounting hole 183b.

The shape of the stroke hole 183a is not particularly limited since the retainer 186 is inserted and the first spring plate 183 is not detached from the second spring plate 184.

The stroke hole 183a is formed to have a step between the upper stroke hole 183d and the lower stroke hole 183e and the diameter d1 of the upper stroke hole 183d is formed to be smaller than that of the lower stroke hole 183e And the upper stroke hole 183d is formed to have a predetermined depth in the direction from the upper surface 183f to the lower surface 183g of the first spring plate and the lower stroke hole 183e May have a predetermined depth from the lower surface 183g of the first spring plate toward the upper surface 183f and the upper stroke hole 183d and the lower stroke hole 183e may be formed to communicate with each other.

The spring mounting hole 183b may be formed through the first spring plate 183 by providing a second pressing spring 185 therein or may be formed in the upper surface direction of the first spring plate 183f And may be formed to have a predetermined depth. That is, the spring mounting hole 183b may be formed by deforming to fit the second pressing spring 185 installed.

The second spring plate 184 is installed to be inserted into the second pressing hole 122 of the second row die 120 and supports the second pressing spring 185 so that the retainer 186 is screwed A spring supporting hole 184b to which the second pressing spring 185 is connected and a plurality of second through holes 184c through which the first pressing portion 181 penetrates are formed.

The second biasing spring 185 may be a disk spring, a gas spring, or a hydraulic spring.

The second pressing spring 185 is formed of a disk spring. The second pressing spring 185 is formed of a disk spring. A plurality of disc springs 185a provided in a spring mounting hole 183b and a spring guide bar 185a through which the lower end of the disc spring 185a is fastened to the spring support hole 184b of the second spring plate 184 185b.

The retainer 186 has a retainer bolt 186a fastened to the stroke hole 183a of the second spring plate 184 and a distance washer 186b that contacts the first spring plate to prevent the first spring plate from rising. As shown in Fig.

That is, when the stroke hole 183a is formed by the upper stroke hole 183d and the lower stroke hole 183e having the step difference, the retainer 186 is elastically deformed by the elastic force (pressing force) of the second pressure spring 185 The distance washer 186b is brought into contact with the stepped portion between the upper stroke hole 183d and the lower stroke hole 183e of the first spring plate 183, The movement range of the plate 183 is limited.

When the upper center pad 250 is lowered by the lowering pressing force of the upper mold 200 in the second pressing section P2, The pressing force of the second pressing spring 185 is applied to the lower center pad 150 through the first spring plate 183 because the second pressing spring 185 contacts the first spring plate 183, So that the adhesion between the material 300 and the upper center pad 250 and the lower center pad 150 is increased. That is, the heat transfer efficiency of the material is improved.

Further, the pressing force of the pressing unit 180 may be adjusted through a separate pressure supply line, or may be variously adjusted according to the molding conditions by adjusting the pressure of the first and second pressing units.

The structure of the present invention as described above is based on a 1-cavity structure having one molding space. As shown in FIGS. 11 to 13, a two-cavity structure having two molding spaces , Two upper dies are provided side by side on the press machine device, and two lower dies having pressing portions corresponding to the respective upper dies are installed side by side on the lower plate.

That is, in a hot stamping apparatus 500 'having a two-cavity structure in which a first mold LH and a second mold RH are driven by a single press machine,

The hot stamping apparatus 500 'includes a first die LH and a second die RH of a second die RH provided in parallel to the press machine 600 and a first die LH, The lower mold of the second mold RH is installed side by side on the lower plate 700 so as to correspond to each of the upper molds 200,

The lower mold 100

A row pad 130 contacting the material to form a blank 300 and having cooling lines 160 and 170 therein,

A first row die 110 on which the row pad 130 is seated and supported,

A second row die 120 disposed on the lower plate so as to be positioned below the first row die 110,

And a pressing unit 180 installed between the first row die 110 and the second row die 120 and pressing one side of the row pad 130 in a supporting and upward direction.

14, the hot-stamping molding apparatus 500 'of the two-cavity structure is provided with a first mold LH or a second mold RH RH, And the lower plate 700. The clearance generated by the thickness error of the workpiece is eliminated.

That is, even with the same material, there is an error with respect to the material thickness t (even if the material of the product produced by a thickness of about 1.5 mm has a thickness error of 1.5 mm or 5% depending on the material) When a material is hot-formed by a hot-stamping apparatus 500 'having a two-cavity structure including a first mold LH and a second mold RH by a press apparatus, (Gap) between the material located in the first mold LH or the second mold RH and the mold is generated due to the material of the first mold LH or the second mold RH. The difference in the physical properties of the two molded articles formed in the two-cavity is caused.

The correction pressurizing unit 800 according to the present invention is used to prevent deterioration and deformation of the one-side molding due to the thickness error of the material. The correction pressurizing unit 800 includes a first mold LH or a second mold die RH 120 (The second mold or the first mold) on the basis of one side mold (the first mold or the second mold) where the correction pressing portion 800 is not provided, and the other side mold (the second mold or the first mold) The material in the first mold LH or the second mold RH is brought into contact with the mold by the same pressure so that uniform cooling is performed.

The pressure application unit 800 may be a gas spring, a hydraulic spring, a disc spring, or the like, as well as a pressurizing unit 180 of the present invention. Preferably, a gas spring or a disc spring is used. That is, the correction pressurizing unit 800 may have the same configuration as the second pressurizing unit.

In addition, the pressing force of the correction pressure unit 800 may be adjusted through a separate pressure supply line, or may be adjusted in response to various conditions as the pressure is adjusted by adjusting the pressure.

Hereinafter, a hot stamping molding method according to the present invention will be described.

FIG. 11 is an exemplary diagram (lowering section) showing an operating state according to the present invention, FIG. 12 is an exemplary view (first pressing section) showing an operating state according to the present invention, (Second pressurizing section) shown in Fig.

The present invention relates to a method of manufacturing a semiconductor device,

A lowering step of lowering the upper mold so that a predetermined gap G is maintained between the upper steel 242 and the work 300 by a press and the upper center pad 250 of the upper mold is brought into contact with the work;

A primary pressing step in which the upper center pad 250 is lowered while a predetermined gap G is maintained between the upper steel 242 and the work 300 so that the work 200 is first press-formed;

The upper die 200 is pressed down so that there is no gap G between the upper steel 242 of the upper die and the work 300 so that the work 300 is secondarily formed, A secondary pressing step in which the molded product 310 is formed by cooling;

And a material discharging step of raising the upper mold and separating the material from the lower mold after the secondary pressing step,

The first pressing portion 181 of the pressing portion 180 presses and supports the low center pad 150 of the low pad so that the work is brought into close contact with the upper center pad 250 of the upper mold,

The secondary pressurizing step presses and supports the low center pad 150 of the low pad on the first pressurizing portion 181 and the second pressurizing portion 182 of the pressurizing portion 180, And the low center pad 150 so as to improve the cooling efficiency of the work.

At this time, the sum of the pressing forces of the first pressing portion 181 and the second pressing portion 182 is set to be smaller than the molding load P of the upper mold. That is, the first pressing portion 181 has a pressing force of 0.05P to 0.3P with respect to the molding load P transmitted to the upper mold by the press, and the second pressing portion 182 has a pressing force of 0.95P to 0.7P And the sum of the pressing forces of the first and second pressing portions 181 and 182 is smaller than the molding load P.

The predetermined gap G is about 2 to 10 mm, preferably about 2 to 6 mm, and more preferably about 5 to 6 mm when the material thickness is about 1.2 to 1.5 mm.

The upper mold lowering step is a step in which the upper mold is lowered in the work direction by the press device. The gas spring stopper 221 provided on the upper mold gas spring 220 contacts the lower gas spring 144 of the lower mold, The upper center pad 250 is brought into contact with the material positioned on the low center pad of the row pad and the upper steel 242 of the upper mold is positioned on the low steel portion 140 of the row pad, (G).

In the primary pressurizing step, the upper center pad 250 of the upper mold is compressed by lowering the upper gas spring 220 by the pressing force of the press, and the material 200 is subjected to the primary press forming, 240 are supported by the low gas spring 144 contacting the gas spring stopper 221 of the upper gas spring so that a predetermined gap G is maintained between the upper steel 242 and the work 300. At this time, the upper center pad 250 is lowered until the lower center pad 150 is brought into contact with the second pressing portion 182 of the pressing portion, and the first pressing portion 181 of the pressing portion moves down the material 300 So that the material is in intimate contact with the upper center pad 25 of the upper mold and the lower center pad 150 of the lower mold.

The secondary pressing step is a step of lowering the upper mold by the pressing force of the press so that the upper mold is lowered by the pressing force of the press so that there is no gap G between the upper mold and the lower mold, The first pressing portion and the second pressing portion of the pressing portion are compressed and the material is pressed upward by the first and second pressing portions so that the entire material surface is pressed against the upper center pad 25 of the upper mold and the lower center pad (150), and the material is cooled by a cooling line installed in the upper and lower molds.

Further, the present invention is characterized in that, when material properties of two molded articles formed in a two-cavity including a first mold (LH) and a second mold (RH) are different after the material discharging step, the first mold ) And the pressing force of the correction pressing portion so that the physical properties of the molded article formed in the second mold (RH) are uniform.

Example

A molding pressurizing part of 80 TON, a second pressurizing part of 320 TON, and a total press-down stroke of 600 mm (molding down part 500 mm, primary pressurizing part 95 to 98 mm, secondary pressurizing part 2, 5 mm) was used to measure the cooling time according to the thickness of the material, and the results are shown in FIG. At this time, as a contrast group, the cooling time for each material thickness was measured in a state in which the first and second pressing portions were not provided.

15 shows the cooling rate difference according to the material thickness. When the cooling time of the present invention having the first and second pressing portions is compared with the contrast group having no first and second pressing portions with respect to the same material thickness, It can be seen that the cooling efficiency is about 50%.

Further, in the case of the present invention including the first and second pressing portions, the upper mold has a speed of 800 mm / sec (takes about 0.63 seconds) in the molding down section, and the material is pressed (About 0.43 sec.) At the first pressurizing section. In other words, it can be seen that the descending speed of the upper mold according to the present invention does not cause a large difference to affect the overall cycle time when the first pressing portion is not provided.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims and their equivalents. Of course, such modifications are within the scope of the claims.

(100): lower mold (110): first low die
(111): upper surface (112): seating hole
(113): lower surface (114): first pressing hole
(115): sliding block (120): second row die
(121): upper surface (122): second pressure hole
(123): Installation hole (130): Low pad
(140): low steel part (141): low body plate
(142): low steel (143): lower molding groove
(144): Low gas spring (150): Low center pad
(151): low pad steel (152): low pad body
(153): a guide post (154): a key
(155): keyway (160, 170): low cooling line
(180): pressing portion (181): first pressing portion
(182): second pressing portion (183): first spring plate
(183a): Stroke hole (183b): Spring mounting hole
(183c): First through hole (183d): Upper stroke hole
(183e): lower stroke hole (183f): upper surface
(183g): lower surface (184): second spring plate
(184a): fastening hole (184b): spring supporting hole
(184c): second through hole (185): second pressing spring
(186): retainer (200): upper mold
(210): Upper die (220): Upper gas spring
(221): gas spring stopper (230): upper pad
(240): Upper steel part (241): Upper steel plate
(242): upper steel (243): upper molding groove
(250): Upper center pad (260, 270): Upper cooling line
(300): material (310): molding
(311): bent portion (312): side wall portion
(313): flange parts (500,500`): hot stamping molding device
(600): Press machine device (700): Lower plate
(800): correction pressure unit

Claims

A lower mold 700 mounted on the lower plate 700 so as to correspond to the upper mold 200 and having a cooling line in the lower mold 700, 1. A hot stamping molding apparatus (500) for molding a mold (300) into a molding (310), comprising:
The lower mold 100 includes a row pad 130 which is in contact with a work 300 to form a work 300 and has cooling lines 160 and 170 therein, A first row die 110 and a second row die 120 fixed to the lower plate 700 to be positioned below the first row die 110; And a pressing portion 180 installed between the dies 120 and pressing and supporting one side of the row pad 130 in the up and down direction,
The pressing unit 180 is configured to press the raw pad 130 primarily to press the raw material 300 against the upper mold 200 and the lower mold 130 by pressing the lower pad 130 against the primary pressing section P1 according to the pressing force of the upper mold 200, And the lower pad 130 is secondarily supported with respect to the secondary pressing section P2 according to the upper pressing force so that the work 300 is supported by the upper and lower molds 200, And a second pressing portion 182 for bringing the first pressing portion 181 and the second pressing portion 182 into close contact with each other,
Wherein the material 300 is brought into close contact with the upper mold 200 and the lower mold 100 uniformly by the pressing portion 180 during the hot forming of the material so that the cooling efficiency is increased. Device.

A hot stamping apparatus (500 ') having a two-cavity structure in which a first mold (LH) and a second mold (RH) are driven by a single press machine,
The hot stamping apparatus 500 'includes a first die LH and a second die RH of a second die RH provided in parallel to the press machine 600 and a first die LH, The lower mold of the second mold RH is installed side by side on the lower plate 700 so as to correspond to each of the upper molds 200,
The lower mold 100 includes a row pad 130 which is in contact with a workpiece to form a work 300 and has cooling lines 160 and 170 inside thereof and a first row die 130 on which the row pad 130 is seated and supported, A second row die 120 disposed on the lower plate so as to be positioned below the first row die 110 and a second row die 120 disposed between the first row die 110 and the second row die 120, And a pressing portion 180 installed to be positioned to press the one side of the row pad 130 in a supporting and upper direction,
The pressing unit 180 is configured to press the raw pad 130 primarily to press the raw material 300 against the upper mold 200 and the lower mold 130 by pressing the lower pad 130 against the primary pressing section P1 according to the pressing force of the upper mold 200, And the lower pad 130 is secondarily supported with respect to the secondary pressing section P2 according to the upper pressing force so that the work 300 is supported by the upper and lower molds 200, And a second pressing portion (182) for making the first pressing portion (181) and the second pressing portion (182) come in close contact with each other.

The method of claim 2,
Characterized in that a correction pressing portion (800) is further provided between the second row die (120) of the first mold (LH) or the second mold (RH) and the lower plate (700) Ping molding device.

The method according to claim 1 or 2,
The row pad 130 includes a lower steel part 140 fixed to the first row die 110 and having a lower forming groove 143 and a lower steel part 140 installed to be movable up and down on the first row die 110 And a low center pad (150) inserted into the lower forming groove (143) of the low steel part (140) to form the bent part (311) of the molded product.

The method of claim 4,
The low steel part 140 includes a low body plate 141 fixed to the first low die 110 and a flange part 313 and a side wall part 312 fixed to the low body plate 141, And a low steel (142)
The lower center pad 150 includes a lower pad steel 151 which contacts the work 300 when the upper mold 200 is lowered by a pressing force and a lower pad 150 which is connected to the lower portion of the lower pad steel 151, And a low pad body (152) for supporting the pad steel (151).

The method of claim 4,
Wherein the low center pads (150) are divided into a plurality of portions around a curved portion (314) of the bent portion (311) of the molded product.

The method of claim 5,
Wherein a lower portion of the lower pad body (152) is further provided with a guide post (153) passing through the first and second row dies (110, 120) and the pressing portion (180).

The method of claim 5, further comprising:
A plurality of steel blocks SB are connected to each other by connection bolts CB and an O-ring is provided between the steel blocks and the steel blocks so that the low steel 142 and the low- ) And the cooling lines (170, 160) located in the row pad steel (151) are connected linearly while maintaining watertightness.

The method according to claim 1 or 2,
The first low die 110 has a lower steel part 140 fixed to the upper surface 111 and a seating hole 112 inserted and seated so that the lower center pad 150 can be moved up and down. The first pressing hole 114 into which the one side of the pressing portion 180 is inserted is formed at a predetermined depth on the lower surface 113 so as to communicate with the seating hole 112 And,
The second row die 120 is formed with a second pressure hole 122 through which the one side of the pressing portion 180 is inserted and supported on the upper surface 121. Inside the second pressure hole 122, A second post hole 123 through which a guide post 153 connected to the center pad 150 is inserted and an installation hole 124 through which one side of the pressing portion is installed are formed. A stamping molding apparatus.

delete

The method according to claim 1 or 2,
The second pressing portion 182 is installed to be positioned between the first row die 110 and the second row die 120 and the first pressing portion 181 is disposed between the second pressing portion 182 and the first row And the second row die (120) is installed on the second row die (120) so that the upper end of the first row die (120) is in contact with the row pad (130) through the die (110).

The method according to claim 1 or 2,
The first pressing portion 181 has a pressing load of 0.05P to 0.3P with respect to a molding load P transmitted to the upper mold by the press,
Wherein a sum of a pressing force of the first and second pressing portions (181, 182) is smaller than a molding load (P).

The method according to claim 1 or 2,
The second pressing portion 182 includes a first spring plate 183 inserted into the first row die 110, a second spring plate 184 inserted into the second row die 120, A plurality of second pressing springs 185 installed between the two spring plates 183 and 184 for elastically supporting the first spring plate 183 and a plurality of second pressing springs 185 passing through the first spring plate 183, And a plurality of retainers (186) bolted to the first spring plate (184) to limit the range of movement of the first spring plate (183) by the second pressure spring (185) Device.

The method according to claim 1 or 2,
Wherein the first pressing portion (181) comprises a gas spring, a disk spring, or a hydraulic spring.

14. The method of claim 13,
Wherein the second pressing spring (185) comprises a gas spring, a disk spring, or a hydraulic spring.

A lower mold 700 mounted on the lower plate 700 so as to correspond to the upper mold 200 and having a cooling line in the lower mold 700, 1. A method for hot stamping molding by a hot-stamping molding apparatus of a one-cavity or two-cavity structure for molding a mold (300) into a molding (310);
A material input step in which the material is placed so as to be seated on the lower pad of the lower mold;
A lowering step of lowering the upper mold so that a predetermined gap G is maintained between the upper steel 242 and the work 300 by a press and the upper center pad 250 of the upper mold is brought into contact with the work;
A primary pressing step in which the upper center pad 250 is lowered while a predetermined gap G is maintained between the upper steel 242 and the work 300 so that the work 200 is first press-formed;
The upper die 200 is pressed down so that there is no gap G between the upper steel 242 of the upper die and the work 300 so that the work 300 is secondarily formed, A secondary pressing step in which the molded product 310 is formed by cooling;
And a material discharging step of raising the upper mold and separating the material from the lower mold after the secondary pressing step,
The first pressing portion 181 of the pressing portion 180 presses and supports the low center pad 150 of the low pad so that the work is brought into close contact with the upper center pad 250 of the upper mold,
The secondary pressurizing step presses and supports the low center pad 150 of the low pad on the first pressurizing portion 181 and the second pressurizing portion 182 of the pressurizing portion 180, And the low center pad (150) so as to improve the cooling efficiency of the workpiece.

The system of claim 16,
When the two moldings formed in the hot-molding apparatus of the two-cavity mold are different from each other in physical properties after the material discharging step, the pressing force of the calibrating pressurizing portion provided between the one lower mold and the lower plate is adjusted or reset, further comprising a correcting step of correcting physical properties of the two molded articles formed in the hot cavity molding apparatus so as to be uniform.