JP6270794B2 - Stamping mold structure and molded product manufactured using the same - Google Patents

Description

  The present invention relates to a mold structure suitable for stamping molding of a resin material and a molded product manufactured using such a mold.

In the field of molding a sheet-shaped resin material, stamping molding is widely performed.
However, in a deep-drawn molded product having a relatively large drawing amount, molding defects such as shortage of wrinkles and wrinkles and cracks are likely to occur.
Patent Document 1 discloses a mold structure that uses a sheet material having an area equal to or larger than the cavity area and presses an end portion of the sheet material with a heel pressing portion provided between upper and lower molds.
However, in such a mold structure, a waste portion is generated in the sheet material, or the sheet material is likely to be crisp in the case of deep drawing.
In addition, there is a problem that warp, deformation, and the like that are harmful to the molded product are likely to occur.

Japanese Patent No. 5332227

It is an object of the present invention to provide a stamping mold structure that is excellent in resin moldability.
Another object of the present invention is to obtain a molded article having excellent shape and quality.

The mold structure for press molding according to the present invention is a mold structure for press molding with an upper mold and a lower mold, wherein one of the upper and lower molds is a convex mold, the other is a concave mold, and the concave mold is formed on the convex mold side. It has a saddle-shaped auxiliary member that protrudes from the surface of the convex shape and has a controlled protrusion amount for preforming.
Here, the saddle-shaped auxiliary member may be a pin shape or a block shape, and the shape may be selected in accordance with the shape of the molded product. Before the convex mold comes into contact with the concave cavity surface, the resin material is formed into a concave concave section. It is intended for preforming in the mold along the shape, so-called preforming.

In the present invention, a protrusion amount of the saddle-shaped auxiliary member is controlled by a control member, and a tip portion for controlling the saddle-shaped amount of the saddle-shaped auxiliary member when the convex mold moves forward toward the concave mold. You may make it have a return pin which contact | abuts on the concave side in a convex side.
If it does in this way, it will become easy to maintain the state where the saddle-shaped auxiliary member pressed the resin material by a fixed amount.
Further, the protruding amount of the hook-shaped auxiliary member may be directly controlled by motor drive control or hydraulic control instead of the return pin.

When the deep-drawn shape of the molded product has a stepped portion or a complicated shape, the saddle-shaped auxiliary member has a protruding amount or a backward movement corresponding to a portion having a different depth of the concave shape of the opposite concave shape. You may make it have several hook-shaped auxiliary members from which quantity differs.
Also in this case, the saddle-shaped auxiliary member is for preforming a resin material in the mold.

  In the present invention, an ejector mechanism for removing the molded product from the mold after molding the molded product may be provided.

In the mold structure according to the present invention, before the convex mold presses the resin material into the concave mold, the saddle-shaped auxiliary member is preliminarily pressed so as to be molded along the shape of the concave section. Generation of misalignment and wrinkles can be suppressed, and the shape is excellent.
Further, deformation due to the residual stress of the product can be prevented.
By using such a stamping mold structure, various molded articles having excellent deep drawability can be obtained.

1 shows a first embodiment of a mold structure according to the present invention. (A) is the state where the upper die is raised, (b) is the state where the saddle-shaped auxiliary member is pre-pressing and molding the resin material, and (c) is molded into the final product shape with the upper die (stamping) (D) shows a state where the upper mold is raised together with the product, and (e) shows a state where the product is discharged from the upper mold. 2 shows a second embodiment of a mold structure according to the present invention. An example in which two different types of saddle-shaped auxiliary members are used for preliminary preforming (preform) in two stages is shown, and (a) to (e) show the flow of molding.

  A structural example of a mold according to the present invention and a flow of molding a product with a mold using the mold will be described below with reference to the drawings, but the present invention is not limited to this.

<First Embodiment>
FIG. 1 schematically shows an example of a mold structure.
In this embodiment, a convex mold is used for the upper mold and a concave mold is used for the lower mold.
The upper mold 10 is fixed to the upper mold mounting portion 2 of the slide 1 and the upper mold 10 is provided with control members 11a and 12a for controlling the protrusion and subtraction of the saddle-shaped auxiliary member 11 and the ejector member (ejector pin) 12. Have
The lower mold 20 is attached to the bolster plate 3 on the bolster side.
Although not shown, the slide is controlled to be lowered and raised by a known means.
Becomes to stamping into the final product shape in the recess 21 of the convex portion 10a and the lower die 20 of the upper mold 10, when directly deep drawing, deviation or occur in the resin material W _0, wrinkles in the deep drawing unit Will occur.
Therefore, a hook-shaped auxiliary member 11 is provided on the upper mold side so as to protrude a predetermined amount from the surface of the convex portion 10a.
The saddle-shaped auxiliary member 11 is provided as a means for preforming at a position where the resin material is easily misaligned or wrinkled, and the shape thereof may be a pin shape or a block shape matching the product shape.
The saddle-shaped auxiliary member 11 is urged in a protruding direction by a control member 11a by a known means such as hydraulic control or an elastic material such as a spring.
The control member 11a is reversely controlled by a return pin 11b.
The protrusion amount may be directly controlled by motor drive control or hydraulic control without using a return pin.
In the present embodiment, an ejector member (ejector pin) 12 is provided on the upper mold 10 side, and this ejector pin has an ejector control member 12a and an ejector return pin 12b. It is used for.
The ejector control member 12a is also controlled to protrude by hydraulic pressure or an elastic material, but is controlled independently from the control member 11a of the saddle-shaped auxiliary member 11.

Next, the flow of stamping molding will be described.
The resin material W ₀ is used as a material of a deep-drawn molded product, and may be a composite material or a laminated material as long as it is a sheet material using a thermoplastic resin as a base material. As an example, a discontinuous fiber reinforcing material may be mentioned, and a laminate of them may be used.
As shown in FIG. 1 (a), these resin materials are heated in advance to a predetermined temperature and placed in the opening of the recess 21 of the lower mold 20.
In this state, the saddle-shaped auxiliary member 11 is projected from the surface of the convex portion 10a of the upper mold 10 by a predetermined amount.
When the upper mold 10 side is lowered by the slide 1, the saddle-shaped auxiliary member 11 presses the resin material W ₀ against the concave portion 21 before the convex section 10 a of the upper mold.
As a result, the resin material W ₀ becomes a preform W ₁ that is preliminarily shaped along the recess 21.
When the hook-shaped auxiliary member 11 presses the resin material W ₀ by a predetermined amount, for example, the tip portions of the return pins 11b arranged at the four corners of the control member 11a abut against the surface of the lower mold 20 so as not to press further. The saddle-shaped auxiliary member moves backward through the control member 11a.
FIG. 1C shows a state in which the preform W ₁ is stamp-molded into a molded product W ₂ by the convex portion 10 a of the upper mold 10 and the cavity surface of the concave portion 21 of the lower mold 20.
Thereafter, the molded article is cooled to increase the upper die 10 as shown in FIG. 1 (d), to advance the ejector pins 12b as shown in FIG. 1 (e), paying out the molded article W _2.
At this time, the hook-shaped auxiliary member 11 may be projected forward in cooperation with the ejector pin 12b.

<Second Embodiment>
This embodiment is an example applied when the deep drawing has a shallow part and a deep part as shown in FIG.
The basic structure is the same as that of the first embodiment, and differences will be mainly described.
As shown in FIG. 2A, in addition to the first saddle-shaped auxiliary member 11, a second saddle-shaped auxiliary member 13 whose protrusion amount is independently controlled is provided.
Therefore, the second hook-shaped auxiliary member 13 also has a control member 13a and a return pin 13b.
In the stage of FIG. 2 (a), the first and second saddle-shaped auxiliary members 11 and 13 are protruded in accordance with the region where the drawing amount is shallow.
As shown in FIG. 2 (b), when the preliminary saddle shape of the shallow portion is performed, the second saddle shape auxiliary member 13 is applied to the surface of the lower die so as to prevent further preliminary saddle shape (in order to keep the wall thickness). The upper die is lowered while being retracted by the return pin 13b in contact therewith.
At this time, the tip of the return pin 11b of the first saddle-shaped auxiliary member 11 is not in contact with the lower concave surface.
Thus, it advances with preformed in FIG deep portion as shown in (c) the first full-shaped auxiliary member 11, is stamping molded product W ₂ of the final shape.
Thereafter, the mold is opened, and the molded product W2 is discharged by the ejector pin 12.
1 and 2 schematically show each saddle-shaped auxiliary member one by one, but in practice, a plurality of saddle-shaped auxiliary members according to the size, shape, etc. of the molded product and as required Second and third saddle-shaped auxiliary members are arranged.

DESCRIPTION OF SYMBOLS 1 Slide 2 Upper mold | type attachment part 3 Bolster plate 10 Upper mold | type 10a Protrusion part 11 Auxiliary member 11a Control member 11b Return pin 12 Ejector member 12a Ejector control member 12b Ejector return pin 21 Recessed part

Claims (2)

A mold structure that is stamped with an upper mold and a lower mold,
One of the upper and lower molds is convex, the other is concave,
Projecting from the convex surface toward the concave on the convex side, and having a saddle-shaped auxiliary member in which the protruding amount is controlled ,
The protruding amount of the saddle-shaped auxiliary member is controlled by a control member,
The control member has a return pin on the convex side, the tip of which comes into contact with the concave side for controlling the vertical amount of the vertical auxiliary member when the convex type moves forward toward the concave type. Die structure for stamping molding. The full type auxiliary member, corresponding to different depths site concave recess shaped opposing stamping according to claim 1, wherein the amount of protrusion or retraction amount and having a plurality of different full type auxiliary member Mold structure for molding.

Images