JPH06286025A - Press molding method for integrated clip using glass fiber reinforced thermoplastic resin sheet - Google Patents

Abstract

PURPOSE:To maintain stiffness of a clip at a level comparable to that of a stampable sheet by a method wherein a thin film is formed between a trapezoidal protuberance of a lower die and a protuberance in upside-down trapezoidal shape of an upper die and glass fibers are made to flow to of the front end of the clip, and punching is made by piercing molding of the thin film after cooling and releasing of the mold. CONSTITUTION:A dent 15 that encloses two sides facing each other of a trapezoidal protuberance 13 of a lower die 11 with a fixed interval kept in between, in the height higher than the protuberance when an upper die 12 is put over the lower die 11 and is equipped at its center with a protuberance 14 in upside-down trapezoidal shape with its underside made to agree with the upper side of the protuberance 13 is provided to the upper die. A stampable sheet 2 in required strength, cut in a specified size, is interposed, after being heated, between the lower die 11 and the upper die 12, and a clip and a housing dent 3 are formed to the sheet 2 by pressure forming, and a thin film is formed at this time along clip lines of the clip. At the time of compressing and flowing the stampable sheet 2 by a press, holding blockes 4 and 4' are communicated with each other on a passage on which the thin film 16 is formed, and thermoplastic resin 2a and glass fibers 2b flow therethrough. After cooling and releasing of the mold, piercing molding is made by punching with a piercing punch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a one-piece clip using a glass fiber reinforced thermoplastic resin sheet, a so-called stampable sheet.

[0002]

2. Description of the Related Art The stampable sheet is a sheet of a composite material of a thermoplastic resin and glass fiber which can be press-formed, and has recently been particularly easy to process, yet has high rigidity and light weight. Its use is expanding as a material for automobiles. By the way, the stampable sheet is one in which a heated sheet is pressed between an upper mold and a lower mold so as to be compressed and flowed. The resin portion of the sheet is easy to flow, but the glass fiber is difficult to flow. With a stampable sheet as the floor plate, a clip having an undercut portion with two relatively long engaging blocks facing each other for fixing the smoke tube and the flashlight to the floor plate is used as the stampable sheet. If it is attempted to be integrally formed, the glass fiber does not exist at the tip of the clip, and the rigidity of this portion may decrease.

Therefore, as disclosed in JP-A-63-87206, there is provided a method for producing a molded article having convex ribs by press molding using the stampable sheet, wherein the sheet is formed before press molding. There is a method for producing a molded product in which the long glass fibers therein are previously cut at the convex rib forming portions, and the long glass fibers are press-fitted together with the synthetic resin into the rib molding groove of the lower mold during press molding.

[0004]

However, in the technique disclosed in the above-mentioned Japanese Patent Laid-Open Publication No. Sho-Sho, the long glass fiber constituting the strength member in the sheet is cut, which may not only reduce the strength. However, there is a problem in that it is difficult to position the long glass fibers in the sheet in advance at the place where the convex rib is formed. Therefore, in the stampable sheet, a metal clip C as shown in FIG. 8 is used as a clip for fixing the smoke tube and the flashlight, and a rivet R is formed by punching a hole in the processed sheet. In general, it is necessary to fix it by means of, and it is unavoidable that man-hours for drilling and riveting and parts costs such as clips and rivets are required. The present invention has been devised as a problem to solve the above problems, and at the same time, at the time of press molding of the stampable sheet, for fixing relatively heavy small parts such as a smoke tube and a flashlight. Provided is a press-molding method for a one-piece clip, which comprises a clip having two relatively long projecting portions facing each other and having an undercut portion integrally with the sheet and without lowering the rigidity of the clip. The purpose is to do.

[0005]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the method for press-molding an integral-type clip using the glass fiber reinforced thermoplastic resin sheet of the present invention is as follows: , A lower die having a trapezoidal protrusion and two sides of the trapezoidal protrusion facing each other when the lower die is combined are surrounded at a constant interval higher than the height of the protrusion, and match the upper surface of the protrusion at the center. And a trapezoidal protrusion of the lower die, in which a clip is integrally formed by press molding with a press machine having an upper die having a concave portion formed with an inverted trapezoidal protrusion having a lower surface. A thin film is formed between the upper trapezoidal protrusion and the inverted trapezoidal projection to allow the glass fiber to flow to the tip of the clip, and after cooling and releasing, the thin film portion is punched out by piercing. Do

[0006]

[Operation] In the molding method of the present invention, a stampable sheet (blank) having a required strength cut into a predetermined size is heated to a predetermined temperature and then placed between the lower mold and the upper mold of the press machine, and the press machine is used. Press molding. By this press molding, the stampable sheet (blank) is compressed and flowed, and the clip is integrally molded with the sheet. At this time, a thin film is formed along a click line described later of the clip. When the stampable sheet (blank) is compressed and flown by the press machine, the thin film is formed between the locking blocks.
Since they are communicated with each other, the glass fibers as well as the thermoplastic resin flow to the vicinity of the tip of the locking block. If cooled after the pressing, the formed stampable sheet is released from the mold, and the stampable sheet is subjected to a pang machine described later, and the thin film is punched in the direction of the arrow by a piercing punch to form a pierce. As a result, the integrated clip 1 is completed.

[0007]

EXAMPLE An integrated clip molded by a press molding method (hereinafter referred to as the molding method of the present invention) of an integrated clip using the glass fiber reinforced thermoplastic resin sheet of the present invention is as shown in FIG. 6 and FIG. The stampable seat 2 is formed integrally with the seat 2 on both sides of a storage recess 3 for small parts K such as the smoke tube, which is formed as necessary. Above the opposing inner surfaces of the locking blocks 4, 4'of a predetermined length, a short upward pushing surface 4a that facilitates the pushing of the small component K,
4'a, and the undercut portions 4b, 4'b opened downward to lock the small parts K pushed in below the inner surface.
Long engaging surfaces 4c, 4'c having a click are formed, and a click line 5 is formed in the length direction at the boundary with the pressing surfaces 4a, 4'a. When the small component K is to be locked by the integrated clip according to the present invention, first, the small component K is pressed between the pressing surfaces 4a and 4'a, so that the locking blocks 4 and 4'are set. When opened, the small part K passes through the click line 5 and the locking surface 4c,
It is pushed between 4'c and placed in the storage recess 3 and at the same time locked by the repulsive force of the locking blocks 4, 4 '.

The molding method of the present invention relates to a molding method for molding the above-mentioned integral clip 1, which will be described in detail with reference to FIGS. 1 to 7. The pressing machine used in the molding method of the present invention includes a lower mold 11 and an upper mold 12 as shown in FIG. That is, the lower die 11 has locking surfaces 4b and 4'b of the locking blocks 4 and 4'of the clip 1 and a thin film 16 described later.
A trapezoidal projection 13 is provided to form the. Further, the upper mold 12 has a locking block 4 of the clip 1,
In order to form the thin film 16 with the pushing surfaces 4a and 4'a of 4 ', the outer side of the locking blocks 4 and 4', and the lower mold 11, the trapezoidal protrusions 13 face each other when combined with the lower mold 11. A lower surface that surrounds two sides (left and right in FIG. 1) that are higher than the height of the protrusion 13 at a constant interval (equivalent to the thickness of the locking blocks 4 and 4 ') and that matches the upper surface of the protrusion 13 at the center. There is a recess 15 having an inverted trapezoidal protrusion 14 having

When it is attempted to form the integrated clip 1 shown in FIGS. 6 and 7 on the stampable sheet 2 by a press equipped with the lower die 11 and the upper die 12 (note that in FIG. The unevenness formed on the lower mold 11 and the upper mold 12 for forming the concave portion 3 is not shown, but this is provided as necessary), and a stampable sheet having a necessary strength cut into a predetermined size. (Blank) 2 to 200
After being heated to about C for 3 to 4 minutes, it is placed between the lower mold 11 and the upper mold 12 of the press machine as shown in FIG. 1, and press-molded by the press machine. By this press forming, the stampable sheet (blank) 2 is compressed and flows, and the clip 1 is integrally formed with the sheet 2 as shown in FIG. 2, and at the same time, the storage recess 3 is formed. A thin film 16 is formed along the click line 5. When the stampable sheet (blank) 2 is compressed and flowed by the press machine, the locking blocks 4 and 4'are connected by the "road" in which the thin film 16 is formed. The glass fibers 2b together with the resin 2a also flow to the vicinity of the tips of the locking blocks 4 and 4 '.

When cooled after the pressing, the formed stampable sheet 2 is released, and the stampable sheet 2 is punched.
Piercing die 18 of the machine 17 as shown in FIG.
After pressing with, the thin film portion 16 is punched by a piercing punch 19 in the direction of the arrow to form piercing. This allows
The integrated clip 1 as shown in FIGS. 6 and 7 is completed.

[0011]

As described above, the method for press-molding an integrated clip using the glass fiber reinforced thermoplastic resin sheet of the present invention is such that after the glass fiber reinforced thermoplastic resin sheet cut into a predetermined size is heated, An inverted trapezoidal shape having a mold and a lower surface that encloses two opposite sides of the trapezoidal projection at a constant interval higher than the height of the projection when combined with the lower mold, and has a lower surface that matches the upper surface of the projection in the center. The clip is integrally formed by compressing and flow by a press machine provided with an upper die having a recess formed with a protruding portion, in which case the trapezoidal protrusion of the lower die and the inverted trapezoidal shape of the upper die. Since a thin film is generated between the protrusion and the glass fiber to flow to the tip of the clip, after cooling and releasing, the thin film portion is punched out by piercing, so that the stampable sheet has a At the same time, the clip having two relatively long engaging blocks facing each other for fixing a relatively heavy small component such as a smoke tube and a flashlight and having an undercut portion is formed at the same time during the press molding. There is an effect that it is possible to provide a method of press-molding an integral clip that is integrally molded with a sheet, and particularly, the vicinity of the tips of the two locking blocks is connected by a "path" that causes the thin film during compression flow. As a result, the glass fiber flows to the vicinity of the tip of the locking block, and the rigidity of the clip can be maintained as in the stampable sheet (blank).

[0012]

[Brief description of drawings]

FIG. 1 is an upper die of a press used in the molding method of the present invention,
FIG. 3 is a vertical cross-sectional view showing a lower mold and a stampable sheet arranged between the lower mold and the lower mold.

FIG. 2 is a perspective view of a clip (before piercing) molded by the molding method of the present invention.

3 is a view in the direction of arrow A in FIG.

FIG. 4 is an enlarged cross-sectional view of a clip (before piercing) showing the flow of glass fibers in the clip.

FIG. 5 is a vertical sectional view showing piercing by a punching machine.

FIG. 6 is a perspective view of a clip (after piercing) molded by the molding method of the present invention.

FIG. 7 is a view on arrow A in FIG.

[FIG. 8] Perspective view of a conventional metal clip 1 clip 2 stampable sheet 3 storage recess 4, 4'locking block 5 click line 11 lower mold 12 upper mold 13 trapezoidal protrusion 14 inverted trapezoidal protrusion 15 recess 16 Thin film 17 Punching machine 18 Piercing die 19 Piercing punch.

Claims (1)

[Claims] 1. A glass fiber reinforced thermoplastic resin sheet cut into a predetermined size is heated, and then a lower die having a trapezoidal protrusion and two opposing sides of the trapezoidal protrusion when combined with the lower die are formed. Compressed by press molding with a press equipped with an upper die having a recessed portion that is surrounded by a fixed interval higher than the height of the protrusion and has an inverted trapezoidal protrusion having a lower surface matching the upper surface of the protrusion at the center. By integrally molding the clip by flow, at that time, a thin film is generated between the trapezoidal protrusion of the lower mold and the inverted trapezoidal protrusion of the upper mold so that the glass fiber can be fluidized to the tip of the clip, After cooling and releasing, the thin film portion is punched out by pierce molding, so that the glass fiber reinforced thermoplastic resin sheet is press-molded into an integral clip.