JP2022161898A - Manufacturing device and manufacturing method for drawn article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wrinkle elimination plate that significantly reduces the price while also maintaining fabrication precision.

SOLUTION: The present invention provides a wrinkle elimination plate 3 that is used in a press for forming a material 4 to be processed into a drawn article having a required shape by means of press forming using a pair of dies consisting of a first die 100 having a cavity 1 and a second die 200 having a core 2. The wrinkle elimination plate 3 comprises a plurality of wrinkle elimination plate pieces 31, 32, 33, 34 having arms extending in two directions along the outer peripheries of the respective corner parts of the opposing surfaces of the cavity 1 and the core 2, and is positioned at the corner parts to be drawn.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention relates to a manufacturing apparatus and manufacturing method for forming a drawn product into a desired shape from a workpiece by press forming.

Drawing using a press machine consists of a pair of upper and lower dies consisting of a first die (concave die, also called die) having a cavity and a second die (convex die) having a core (or punch). It is common to use
Drawing is widely used in press molding of fiber reinforced composite resin (so-called FRP), in addition to conventional press molding with a metal plate as a workpiece (blank or work). ing.
When the material to be processed is a fiber reinforced composite resin or a composite of the fiber reinforced composite resin and metal, the reinforcing fiber material such as glass fiber or carbon fiber may be thermosetting resin such as epoxy resin, phenol resin, polyester resin, or thermoplastic resin. An intermediate material (prepreg) impregnated with a resin and semi-cured is generally used. This prepreg is heated and pressurized by a press machine to manufacture a desired processed product.

In drawing a fiber-reinforced composite resin using a press, the reinforcing fiber material is drawn into the drawing space (the gap between the cavity and the core) as the core enters the cavity.
This pulling is conspicuous at the corners of the processed product, causing local irregular tensile strain and expansion and contraction of the spacing of the reinforcing fiber material, changing the density of the reinforcing fiber material, and causing uneven distribution of the resin, resulting in the deformation of the processed product. Side walls and the like are wrinkled and, in some cases, fibers are broken. This causes partial variations in the strength of the processed product, and causes problems such as a decrease in the overall strength, resulting in quality deterioration of the molded product and generation of defective products.

In order to avoid the occurrence of such problems, a work piece holding jig called a "wrinkle removing plate" has been conventionally used. The wrinkle removing plate is a frame-shaped plate (frame-shaped plate) that surrounds the outer edge of the workpiece (assumed to be prepreg below), and serves as a blank holder that holds the workpiece at a predetermined position in the mold. It also has functions.

FIG. 7 is a schematic diagram for explaining an example of a known drawing machine, (a) is a side view of a drawing machine consisting of a first mold having a cavity 1 and a second mold having a core 2, (b ) is a top plan view of the second mold with the first mold and the work piece removed in (a).

This drawing machine consists of a pair of dies as described above. A prepreg as material 4 is drawn.
A wrinkle removing plate 3 is installed along the outer circumference of the core 2 of the second mold 200 .
A drawing machine of the type shown in FIG. The core 2 of the second mold 200 is press-fitted. There is also a form in which a pair of molds is upside down.

As shown in plan view in FIG. 7(b), the wrinkle removing plate 3 is composed of a single frame-shaped plate body, and along the outer edge of the core 2 provided in the second mold 200, It is installed so that it can go up and down by going around. The wrinkle removing plate 3 is normally made of the same metal plate as the metal mold.
During the drawing process, a workpiece (for example, a prepreg) 4 is placed on the wrinkle removing plate 3 (the state shown in FIG. 7(a)). This wrinkle removing plate 3 can be moved up and down by a stretchable member 5, and is lifted before the second mold 200 starts to rise or at the same time as the second mold 200 starts to rise. and the upper surface (facing surface) of the second mold 200.

Next, the second die 200 is further raised in the direction of the large arrow by the pressurizing mechanism 6, and the core 2 is press-fitted into the cavity 1, thereby drawing the workpiece 4 into a predetermined shape.

The wrinkle removing plate 3 is also a means for holding and aligning the work piece 4. In the drawing process, the structure of the peripheral portion of the work piece generated in the drawing process of the work piece is appropriately spaced between the cavity and the core. Its main role is to move and avoid breakage due to wrinkles occurring mainly on the side walls and reduction in wall thickness.

In addition to patent documents such as Patent Document 1 and Patent Document 2, for example, there are a number of general documents that disclose the prior art relating to this type of wrinkle removing plate.
Patent Document 1 uses an upper mold with a concave portion (cavity) and a lower mold with a convex portion (core), and a wrinkle removing plate arranged on the outer periphery of the lower mold for fiber reinforced composite material molding. An apparatus and method for stamping articles is disclosed.

Further, Patent Document 2 discloses a general-purpose press having a concave mold (corresponding to the upper mold called die), a convex mold (corresponding to the lower mold called punch), and a wrinkle removing plate. , discloses a method and apparatus for avoiding wrinkling and breakage of molded products during sheet material drawing by injecting high pressure liquid into the mold.

Japanese Patent No. 6587771 JP-A-07-144234

In the drawing process, reinforcing fibers are drawn in at the drawn portion where the concave portion (cavity) and the convex portion (core) are combined, especially in the corner portion, resulting in unevenness and cutting between fibers, reduction in the thickness of the resin layer, etc. Trouble is likely to occur. If only the wrinkle removing plate (also called wrinkle suppressing plate) used in the drawing machine is used, the wrinkle removing plate and the upper die may pinch each other. There is a risk that it will not be possible to obtain a processed product with a high

The main function of the wrinkle removing plate is to avoid such excessive retraction of the constituent members of the work material and to ensure proper retraction.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of making it easier to draw in a workpiece in a manufacturing apparatus equipped with the above-described conventional wrinkle removing plate.

In order to achieve the above object, the apparatus and method for manufacturing a drawn product according to the present invention are characterized by using at least one spacer arranged on the wrinkle removing plate.
A representative configuration of the present invention is described below.

According to the present invention, a workpiece 4 is drawn into a desired shape by press molding using a pair of upper and lower dies consisting of a first die 100 having a cavity 1 and a second die 200 having a core 2. A wrinkle-removing plate 3 used in a press machine for molding was configured as follows.

[1] An apparatus for manufacturing a drawn product having a desired shape of a workpiece by press molding using a pair of upper and lower molds comprising a first mold having a cavity and a second mold having a core,
a wrinkle-removing plate disposed around a surface of the core that is perpendicular to the surface in contact with the workpiece;
and a spacer disposed on the wrinkle removing plate and having a thickness equal to or greater than that of the workpiece.
[2] Press forming using a pair of upper and lower molds consisting of a first mold having a cavity and a second mold having a core to draw a work material into a desired shape using a manufacturing device for drawing products wherein the manufacturing apparatus comprises
a wrinkle removing plate disposed around a surface of the core that is perpendicular to the surface in contact with the workpiece;
at least one spacer disposed on the wrinkle removing plate;
The manufacturing method is
placing the workpiece on the wrinkle removing plate;
a step of raising the second mold together with the wrinkle removing plate to bring the surface of the core in contact with the work material into contact with the work material;
a step of further raising the second mold while drawing the work material between the core and the cavity to pressurize the work material;
and a step of lowering the second mold to obtain a drawn product.
[3] The material to be processed is a thermoplastic resin, a thermosetting resin, a fiber-reinforced composite resin containing a thermoplastic resin or a thermosetting resin, or a composite material of these resins and a metal selected from aluminum, high-tensile strength and titanium. The manufacturing method according to [2].
[4] The manufacturing method according to [2], wherein the workpiece is a laminate.
[5] The wrinkle-removing plate comprises a plurality of wrinkle-removing plate pieces arranged outside the core, each of the wrinkle-removing plate pieces having a pair of arms, one of which extends perpendicularly to the other. The production method according to [2].
[6] The manufacturing method according to [2], wherein the spacer has a thickness equal to or greater than that of the workpiece.

It goes without saying that the present invention is not to be construed as being limited to the above configuration and the configurations of the examples described in the embodiments to be described later, and that various modifications are possible without departing from the technical concept of the present invention. .

According to the configurations of [1] and [2] above, by providing the wrinkle removing plate, it is possible to avoid unevenness and cutting between fibers and decrease in the thickness of the resin layer, thereby causing wrinkles and breakage (molded product tearing and cracking) can be suppressed. Furthermore, since the spacer is used, excessive pinching between the wrinkle removing plate and the upper mold can be prevented, and the workpiece can be pulled in more easily.

The configurations of [1] and [2] above are the work material of [3] (thermoplastic resin, thermosetting resin, thermoplastic resin or fiber reinforced composite resin containing thermosetting resin, or these resins and aluminum, A composite material with a metal selected from high tensile strength and titanium) is particularly useful. These materials tend to undulate when pressed, and once undulated, it becomes difficult for the material to be drawn in between the cavity and the core. It can be pulled in easily.

The configurations [1] and [2] above are useful for the laminate described in [4] above. In the case of a laminate, for example, it is assumed that prepregs made of fiber-reinforced composite resin are laminated, but lamination increases the thickness of the material to be processed, making it difficult to pull it in. However, by providing the spacer, it is possible to improve the easiness of retraction, so even a laminated body can be manufactured as a drawn product with high accuracy.

By adopting the wrinkle removing plate of the above [5] in the above configurations [1] and [2], the wrinkle removing plate can be manufactured at a low cost, and excessive retraction of the workpiece can be suppressed. For example, if the non-worked material is metal, the shape of the corner can be formed by making that part thinner due to its ductility, but the reduced metal moves to other parts, so the increased metal The metal plate becomes wavy. Wavy material (material with unevenness) will not be drawn into the mold as a result. Therefore, when the workpiece is metal, it is desirable to place wrinkle removing plates around the periphery (360°) so as to prevent unevenness from appearing on the workpiece. On the other hand, in the case of fiber reinforced composite resin (CFRP), since the corners are formed by evenly gathering the fibers, the range is limited to the part that forms the corner, and the other parts are less wavy, so the surrounding There is no need to place a wrinkle removing plate over the surface. Rather, placing the wrinkle suppressors only at the four points near the corners makes it easier to obtain a high-precision fiber-reinforced composite molded product without crushing the workpiece more than necessary.

In addition, according to the above configuration (6), the part of the workpiece that is in contact with the wrinkle removing plate is not subjected to pressure from the first mold, so that it is easy to draw in and the thick workpiece It is also possible to correspond to

FIG. 1 is a schematic diagram of a manufacturing apparatus of Example 1 to which wrinkle removing plates 3 and spacers 8 are applied. FIG. 2 is a schematic diagram of the workpiece 4 arranged on the wrinkle removing plate 3 in the manufacturing apparatus of the first embodiment. FIG. 3 is a schematic diagram showing that the second mold comes into contact with the workpiece 4 and begins to deform in the manufacturing apparatus of Example 1. As shown in FIG. FIG. 4 is a schematic diagram showing a state in which the first mold and the second mold are closest to the workpiece 4 and are heated and pressurized in a predetermined shape in the manufacturing apparatus of the first embodiment. . FIG. 5 is a schematic diagram showing a state in which a drawn product is obtained by lowering the second mold in the manufacturing apparatus of Example 1. FIG. FIG. 6 is a schematic diagram of a manufacturing apparatus of Example 2, in which wrinkle removing plates 3 are provided outside the four corners of the core as wrinkle removing plate pieces. FIG. 7 is a schematic diagram of a conventional manufacturing apparatus without spacers.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Example 1
FIG. 1 is a schematic diagram of a drawn product manufacturing apparatus (drawing machine) to which Embodiment 1 of the wrinkle removing plate used in the press machine according to the present invention is applied. A side view of a drawing machine consisting of a die and a second die having a core 2, (b) is a plan view of the main parts of the second die from which the first die and the workpiece in (a) are removed. It is a diagram.

This drawing machine is composed of a pair of molds in the same manner as the one described with reference to FIG. Then, the prepreg laminate as the workpiece 4 is drawn.

In this embodiment, a rectangular wrinkle-removing plate 3 is arranged on the outer circumference of the core 2 of the second mold 200, and the wrinkles are removed along the straight part of the outer circumference of the rectangular wrinkle-removing plate 3. Four rectangular parallelepiped spacers 8 are provided on the mounting plate 3. - 特許庁

(wrinkle removing plate)
The wrinkle removing plate 3 is provided on the second mold 200 so as to be movable up and down together with the second mold 200 . The wrinkle removing plate 3 is connected to the second mold 200 by an elastic member 5 configured by a spring mechanism.
Before the second mold 200 starts to rise, the work material 4 is placed on the surface of the wrinkle removing plate 3 and the second mold 200 is lifted to carry out drawing.
Therefore, the wrinkle removing plate 3 has a flat surface on which the workpiece 4 can be placed, and has a hole near the center of the flat surface through which the core 2 of the second mold 200 can rise.

(spacer)
In the drawing machine of Example 1, a spacer 8 is provided on the flat surface of the wrinkle removing plate 3 on which the workpiece 4 can be arranged. The spacers 8 are arranged on the wrinkle removing plate 3 along the outer edge of the wrinkle removing plate 3, and four rectangular parallelepiped spacers 8 are provided on each side. The position of the spacer is not particularly limited as long as it is on the plane of the wrinkle removing plate 3, and can be changed according to the size and shape of the workpiece 4. FIG. It may be moved during molding.

(Work material)
The material that can be drawn by the drawing machine of the first embodiment (material of the workpiece 4) is not particularly limited, but in addition to simple metals such as plate-shaped iron, aluminum, high-tensile steel, and titanium, fibers can be used. Examples include reinforced composite resins, thermoplastic resins, thermosetting resins, and composites of these resins and metals (aluminum, high-tensile steel, titanium), and drawing can also be performed on laminates of these. A prepreg can be used as a fiber-reinforced composite resin, a thermoplastic resin, a thermosetting resin, or a composite material. Prepregs are preferred because they are easy to handle.
Fibers of the fiber-reinforced composite resin include glass fibers, carbon fibers, organic fibers, and the like.

(Manufacturing method of drawn product)
A drawing method using the drawing machine of Example 1 will be described. In this embodiment, as the workpiece 4, a laminate of prepregs made of carbon fiber reinforced composite resin (thermosetting resin) is used. First, as shown in FIG. 1(a), the workpiece 4 is placed on the wrinkle removing plate 3 so as not to come into contact with the spacer 8. Then, as shown in FIG. Then, the workpiece 4 is heated by a heater (not shown) provided inside or outside the second mold 200 .

After heating the workpiece 4 to a predetermined temperature, the second mold 200 and the wrinkle removing plate 3 provided therein are raised until the spacer 8 comes into contact with the first mold 100 (upper mold) (see FIG. 2). ). At this time, the workpiece 4 can come into contact with the first mold 100 together with the spacer 8 , or it can be set so that the workpiece 4 does not come into contact with the first mold 100 . In order to prevent the workpiece 4 from coming into contact with the first mold 100 , the height of the spacer 8 is made higher than the height of the workpiece 4 . From the viewpoint of making it easier for the workpiece 4 to be pulled into the cavity 1 , it is preferable that the workpiece 4 at this time should not come into contact with the first mold 100 .

After the spacer 8 contacts the first mold 100, the second mold 200 having the core 2 is further raised. At this time, due to the contraction of the expandable member 5, the wrinkle removing plate 3 and spacer 8 maintain their positions, only the second mold 200 (core 2) is further raised, and the workpiece 4 is separated into the cavity 1 and the core 2. , and further rises while deforming the workpiece 4 (see FIG. 3).

With the core 2 entering the cavity 1 and pressurizing the workpiece 4, the first die stops rising at a predetermined position. Heating is continued at the position where the rise is stopped, and pressure and heating are continued so as to obtain a desired shape. The stationary time of the second mold 200 ranges from 10 seconds to 20 minutes.

After performing necessary pressurization and heating, the heating is stopped, and after cooling to a predetermined temperature, the second mold 200 is lowered and the drawn product is removed.

Example 2
Example 2 shown in FIG. 6 is another aspect of the present invention. Example 1 relates to the wrinkle removing plate 3 having one rectangular surface with a hole for inserting the core 2 in the center. It is a wrinkle removing plate composed of wrinkle removing plate pieces 31, 32, 33 and 34 arranged outside four corners 30 of a substantially rectangular shape (see FIG. 6(b)). In addition, the finishing work for obtaining the predetermined manufacturing accuracy of the wrinkle-removing plate pieces 31, 32, 33, and 34 can be shortened, and the cost can be reduced as a whole.

The present invention tends to be effective in the case of a relatively large mold. If there is, it is more preferable, and if it is 2000 mm or more, it is even more preferable.

Even when the wrinkle-removing plate is made up of a plurality of such wrinkle-removing plate pieces, by providing the spacer 8 on the upper plane of each wrinkle-removing plate piece 31, 32, 33, 34, the Similar to 1, it is possible to make it easier to draw in the workpiece 4 . Although the shape of the spacer 8 is L-shaped in FIG. 6, the shape of the spacer 8 is not particularly limited, and a rectangular parallelepiped or a curved rectangular parallelepiped can also be used.

Although the core 2 has a substantially rectangular upper plane with rounded corners, the present invention is not limited to a substantially rectangular shape and can be applied to a circular or elliptical shape. A plurality of wrinkle-removing plate pieces (with spacers on the wrinkle-removing plate pieces) can be provided around the periphery.

DESCRIPTION OF SYMBOLS 1... Cavity 2... Core 3... Wrinkle-removing plate 31, 32, 33, 34... Wrinkle-removing plate piece 4... Work material 5... Expandable member 6... Pressurization Mechanism 7 Machine frame 8 Spacer 100 First mold 200 Second mold

Claims (6)

A manufacturing apparatus for drawing a work material into a desired shape by press molding using a pair of upper and lower molds comprising a first mold having a cavity and a second mold having a core,
a wrinkle-removing plate disposed around a surface of the core that is perpendicular to the surface in contact with the workpiece;
and a spacer disposed on the wrinkle removing plate and having a thickness equal to or greater than that of the workpiece. A method of manufacturing a drawn product of a desired shape by press molding using a pair of upper and lower molds consisting of a first mold having a cavity and a second mold having a core. wherein the manufacturing apparatus is
a wrinkle removing plate disposed around a surface of the core that is perpendicular to the surface in contact with the workpiece;
at least one spacer disposed on the wrinkle removing plate;
The manufacturing method is
placing the workpiece on the wrinkle removing plate;
a step of raising the second mold together with the wrinkle removing plate to bring the surface of the core in contact with the work material into contact with the work material;
a step of further raising the second mold while drawing the work material between the core and the cavity to pressurize the work material;
and a step of lowering the second mold to obtain a drawn product. The material to be processed is a thermoplastic resin, a thermosetting resin, a fiber-reinforced composite resin containing a thermoplastic resin or a thermosetting resin, or a composite material of these resins and a metal selected from aluminum, high-tensile strength and titanium. Item 2. The manufacturing method according to item 2. 3. The manufacturing method according to claim 2, wherein the workpiece is a laminate. 3. The wrinkle-removing plate comprises a plurality of wrinkle-removing plate pieces arranged outside the core, each of the wrinkle-removing plate pieces having a pair of arms, one of which extends perpendicularly to the other. The manufacturing method described in . 3. The manufacturing method according to claim 2, wherein the spacer has a thickness equal to or greater than that of the workpiece.

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