KR20170070965A

KR20170070965A - Press mold apparatus

Info

Publication number: KR20170070965A
Application number: KR1020150178730A
Authority: KR
Inventors: 문화식
Original assignee: 에스엠티(주)
Priority date: 2015-12-15
Filing date: 2015-12-15
Publication date: 2017-06-23

Abstract

The present invention discloses a press mold apparatus capable of reducing the spring back by improving the structure of the upper and lower molds in order to secure the stretchability of the outer shell of the automobile. In order to achieve the above object, the present invention provides a method of manufacturing a metal mold, comprising: a lower mold fixed to an upper portion of a base plate, the lower mold having a center surface and a holding surface formed on an outer periphery of the center surface, A pressing member disposed on an outer periphery of the upper mold for holding the blank material by pressing the holding surface before the upper mold is engaged with the center face, And a press die.

Description

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a press mold apparatus, and more particularly, to a press mold apparatus capable of reducing the spring back by improving the structure of upper and lower molds in order to secure the stretchability of the outer shell of an automobile.

In general, various methods for improving the weight saving and safety of automobiles have been attempted in the industrial field, and as a method thereof, the use of high tensile steel is increasing. Such a high-strength steel plate is applied to a steel plate having a tensile strength stronger than that of a general steel plate, particularly to an outer plate of an automobile. At this time, the outer plate of the automobile is manufactured through the press die apparatus using the press draw forming and fixing method. However, securing the stretchability is an important issue for securing the flexure and rigidity of the shell plate.

As a prior art related to the present invention, there is a " bending die apparatus for preventing springback ", KR Patent Publication No. 10-2005-0067978 (published on May 5, 2005).

The present invention provides a press mold apparatus capable of securing the stretchability of an outer shell of an automobile by engaging an upper mold and a lower mold with a forming structure in a state of holding a blank material by using a pressing member provided on the outer periphery of the upper mold, There is

According to the technical idea of the present invention, a lower mold is fixed to an upper portion of a base plate, and has a center surface and a holding surface formed on the outer circumference of the center surface to seat the blank material on the center surface and the upper surface of the holding surface. An upper mold disposed opposite to an upper portion of the lower mold and lifted and lowered to engage with a center surface of the lower mold; And a pressing member disposed on an outer periphery of the upper mold and holding the blank material by pressing the holding surface before the upper mold is engaged with the center surface. The upper mold is preferably temporarily stopped when the pressing member presses the holding surface, and then proceeds to stroke. The pause time is preferably in the range of 0.5 to 0.9 seconds. It is preferable that the pressing member is any one of a gas spring and a hydraulic cylinder. According to another aspect of the present invention, there is provided a lower mold comprising: a lower mold fixed to an upper portion of a base plate, the lower mold having a tapered central surface protruding upwardly and a holding surface formed on an outer periphery of the center surface; An upper mold disposed to face the upper portion of the lower mold and lifted and lowered to be engaged with the lower mold; A blank holder on which a blank material is placed, the blank holder being disposed on an outer periphery of the lower mold; And a pressing member which is fixed to the outer periphery of the upper mold and holds the blank material by pressing the upper surface of the blank holder before the upper mold is engaged with the lower mold . At this time, it is preferable that the blank holder is located above the holding surface of the lower mold

The press die apparatus of the present invention has a structure in which the blank material is held from the outside by using a pressing member provided on the outer periphery of the upper die and the upper die and the lower die are engaged after a predetermined time, Thereby providing an effect of securing stretchability. Accordingly, the press-molding apparatus of the present invention secures the rigidity of the outer shell of the automobile, thereby reducing the occurrence of springback and providing an effect of achieving better stability.

FIG. 1 is a view schematically showing a state in which a blank material is placed on a press die apparatus according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of a press die apparatus according to a first embodiment of the present invention, FIG. 3 is a view showing a state in which a blank material is completely formed by using the press-molding die apparatus according to the first embodiment of the present invention, and FIG. 4 is a cross- FIG. 5 is a view illustrating a state in which a blank material is held on a press die device, and FIG. 5 is a view illustrating a state in which a blank material is held in a press die device according to a second embodiment of the present invention.
FIG. 6 is a view showing a state in which molding of a blank material is completed by using the press-mold apparatus according to the second embodiment of the present invention. FIG.

Hereinafter, a press die apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

It is intended that the invention be described in its entirety by reference to the appended claims and their equivalents. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. FIG. 1 is a view schematically showing a state in which a blank material is placed on a press die apparatus according to a first embodiment of the present invention.

1, the press mold apparatus 100 according to the first embodiment of the present invention includes a base plate 110, a lower mold 120, an upper mold 130, a pressing member 140, . The lower mold 120 remains fixed to the base plate 110 during the molding process. The lower mold 120 has a center surface 122 and a holding surface 124. [

At this time, the center surface 122 means a central portion on the upper side of the lower mold 120. The holding surface 124 is formed on the outer circumference of the center surface 122.

The upper mold 130 is arranged to face the upper portion of the lower mold 120. The upper mold 130 is adjusted so as to be engaged with the center surface 122. At this time, the upper mold 130 can be actively controlled by hydraulic pressure or the like.

The pressing member 140 is disposed around the outer periphery of the upper mold 130. [ At this time, the pressing member 140 presses the holding surface 124 to hold the blank material 10 before the upper mold 130 is engaged with the center surface 122.

In this case, the pressure member 140 may be a gas spring or a hydraulic cylinder. Here, the configurations of the present invention described above can be collectively driven by a control unit (not shown), and the user can change the driving environment according to the working environment. Therefore, such driving control related matters need not be limited to the present invention. As shown in FIG. 1, the present invention shows a loading state for forming a blank material 10. The upper mold 130 is located at a top dead center (TDC), and the lower mold 120 is fixed in a state where the blank material 10 is seated.

In this state, the upper mold 130 and the pressing member 140 begin to descend.

FIG. 2 is a view illustrating a state in which a blank material is held in a press die apparatus according to a first embodiment of the present invention. 2, the press mold apparatus 100 according to the first embodiment of the present invention includes a base plate 110, a lower mold 120, an upper mold 130, a pressing member 140, . Since the above-described configurations are the same as those described above with reference to FIG. 1, redundant description will be omitted. However,

For the sake of better understanding of the drawings, parts that are partially overlapped may be included.

The pressing member 140 holds the blank material 10 from the outside before the upper mold 130 descends. The pressing member 140 is brought into contact with the holding surface 124 of the lower mold 120 so that the blank material 10 contacts the central surface 122 of the lower mold 120

. It is preferable that the upper mold 130 is temporarily stopped after the pressing member 140 presses the holding surface 124 on which the blank material 10 is placed. At this time, it is preferable that the pause time is in the range of 0.5 to 0.9 seconds. If the pause time is shorter than 0.5 second, it is difficult to secure the shape fixability of the blank material 10. If the pause time exceeds 0.9 sec, the disadvantage of the process cycle delay becomes larger than the advantage of securing the shape fixability of the blank material 10 . Therefore, it is preferable that the time for which the blank material 10 is temporarily stopped while being pressed by the pressing member 140 to the holding surface 124 is in the range of 0.5 to 0.9 seconds.

3 is a view showing a state in which molding of a blank material is completed by using the press-mold apparatus according to the first embodiment of the present invention.

Referring to FIG. 3, after the pressing member 140 first presses the outer surface of the blank material 10, the upper mold 130 is struck after being stopped for a predetermined time as described above. After this series of processes, the forming of the blank material 10 is completed.

The upper mold 130 and the pressing member 140 reach the bottom dead point so that the upper mold 130 and the pressing member 140 and the lower mold 120 are in close contact with each other with the blank material 10 interposed therebetween do. It is preferable that the lowering pressure of the pressing member 140 is strengthened in the section immediately before the molding is completed because the plasticity is to be ensured by allowing the plastic deformation to be performed immediately before the molding is completed. 4 is a view schematically showing a state in which a blank material is placed on a press die apparatus according to a second embodiment of the present invention.

4, the press mold apparatus 200 according to the second embodiment of the present invention includes a base plate 210, a lower mold 220, an upper mold 230, a pressing member 240, And a blank holder 250. Since the remaining structures except for the lower mold 220 and the blank holder 250 are the same as those of the first embodiment of the present invention, a duplicate description will be omitted. In order to facilitate the understanding of the drawings, the above-described contents may be partially duplicated, and the contents not described above will be mainly described.

The lower mold 220 is fixed to the upper portion of the base plate 210 and includes a tapered center surface 222 protruding upwardly and a holding surface 224 formed on the outer circumference of the center surface 222 do. The blank holder 250 has a blank material 10 mounted thereon and disposed on the outer circumference of the lower mold 220. It is preferable that the blank holder 250 is located above the holding surface 224 of the lower mold 220. Further, it is preferable that the blank holder 250 is not fixed to be moved up and down according to external pressure but fixed. In this state, the upper mold 130 and the pressing member 140 begin to descend. FIG. 5 is a view illustrating a state in which a blank material is held in a press die apparatus according to a second embodiment of the present invention. FIG. 6 is a cross- Is completed. Fig.

5 and 6, the press mold apparatus 200 according to the second embodiment of the present invention mainly includes a base plate 210, a lower mold 220, an upper mold 230, Member 240 and a blank holder 250. As shown in FIG. The upper mold 230 is struck after the pressing member 240 first presses the outer surface of the blank material 10 and then stops for a predetermined time as described above. After this series of processes, the forming of the blank material 10 is completed. When the upper mold 230 and the pressing member 240 reach the bottom dead center, the upper mold 230 and the pressing member 240, the lower mold 220 and the blank holder 250 are separated from the blank material 10 As shown in Fig. It is preferable that the lowering pressure of the pressing member 240 is strengthened in the section immediately before the molding is completed because the plasticity is to be ensured by allowing the plastic deformation to be performed immediately before the molding is completed. As described above, the press die apparatus of the present invention has a structure in which the blank material is held from the outside by using a pressing member provided on the outer periphery of the upper die, and the upper die and the lower die are engaged after a predetermined time. Accordingly, the press die apparatus of the present invention can provide the effect of securing the stretchability of the blank material during the press forming step. Further, the press die apparatus of the present invention can provide the effect of securing the rigidity of the outer shell of the automobile to reduce the occurrence of springback, and to achieve better stability. While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10: Blank material
100, 200: Press mold device
110, 210: Base plate
120, 220: Lower mold
122, 222: center face
124, 224: Holding face
130, 230: Upper mold
140, 240: pressing member
250: Blank Holder

Claims

Claim 1
A lower mold fixed to an upper portion of the base plate and having a center surface and a holding surface formed on the outer circumference of the center surface to seat the blank material on the upper surface of the center surface and the holding surface, An upper mold that is lifted and lowered to engage with a center surface of the lower mold; And a pressing member disposed on an outer periphery of the upper mold and holding the blank material by pressing the holding surface before the upper mold is engaged with the center surface.
Claim 2
The press mold apparatus according to claim 1, wherein the upper mold is temporarily stopped when the pressing member presses the holding surface, and then proceeds to stroke.
Claim 3
The press mold apparatus according to claim 2, wherein the pause time is in the range of 0.5 to 0.9 seconds.
Claim 4
The press-molding die apparatus according to claim 1, wherein the pressure member is one of a gas spring and a hydraulic cylinder.
Claim 5
A lower mold fixed to an upper portion of the base plate and having a tapered central surface protruding upwardly and a holding surface formed around an outer periphery of the center surface, the upper mold being disposed to face the upper portion of the lower mold, A blank holder on which a blank material is placed on an upper mold to be lifted and lowered and arranged around an outer periphery of the lower mold; And
And a pressing member disposed in a state fixed on the outer periphery of the upper mold and holding the blank material by pressing the upper surface of the blank holder before the upper mold is engaged with the lower mold.
Claim 6
The press mold apparatus according to claim 5, wherein the blank holder is located above the holding surface of the lower mold.