JPS5835451B2 - Method for applying a rod-shaped object to a synthetic resin hollow molded body in blow molding and its molded product - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for inserting a rod-like object into a synthetic resin hollow molded body in blow molding, and a molded product thereof, and more particularly, to It is an object of the present invention to provide a method by which the end of a rod-like object can be inserted into a separate hollow position, and a molded product in which the end of the rod-like object is firmly integrated.

An example of implementation of the present invention will be described in detail below based on the drawings.

First, to explain the apparatus used in the method of the present invention, a nozzle 5 facing the molding die is in communication with an extruder and a compressed air supply device (both not shown), and the melt sent from the extruder is It is possible to mold synthetic resin into a tube shape and pour out the parison a continuously, and to supply air into the parison a to be poured.

Further, the nozzle 5 is connected to a separate drive device (not shown) and is movable along the molding groove 2 of the mold 1.

The molding die consists of a pair of mold 3, which is an upper mold, and mold 1, which is a lower mold, and the overlapping surfaces thereof have molding grooves 2.4 and 2.4 that match the shape of the hollow molded body A to be molded. An insertion groove 8°9 for the rod-shaped object B communicating with the groove is carved, and a parison introduction hole 6 at one end of the groove is provided with a cut-off collar 7 for the parison A at the other end.

Next, implementation of the present invention using such an apparatus will be explained.

First, the vertical legs C2C are placed on the left and right sides of the molding groove 2 of the mold 1.

This vertical leg C is made of metal or synthetic resin and has a leg length equal to the distance between the rod-like object B1 (described later) and the second surface of the molding groove, and a thickness smaller than the diameter of the rod-like object end B1, and is made of metal or synthetic resin. On the contact end side of the leg section C2, the end edge thereof has a widening shape.
Equipped with.

On the other hand, the contact end side with the rod-like object end B1 via the body C1 has a pedestal part C3 that has a similar shape to the side surface of the rod-like object end B1 so that the rod-like object end B1 can be stably joined. It has a constricted shape with respect to the leg section C2 and the pedestal section C3.

Further, the width of the vertical leg C may be equal to or shorter than the length of the rod-like object end B1 facing into the forming groove 2, and is not limited.

Next, the rod-like object end B1 is placed on the vertical legs C, C in a substantially horizontal manner.

Next, the nozzle 1 located on the side of the forming groove 2 of the forming mold 1 is moved along the forming groove 2 while continuously pouring out the parison a from its spout, and the parison a flows into the forming groove 2.

At this time, if the rod-like object end B1 extends to the center of the forming groove 2, the parison a will cross over the end surface of the rod-like object at the position of the rod-like object end B1.

After that, fit the mold 3 together and cut out one side of the parison a.
Subsequently, compressed air is forced into the parison a.

As a result, the parison a comes into pressure contact along the wall surface of the bulge-forming groove 24, and after starting pressure contact at the end B1 of the rod-shaped object so as to wrap around the eye end, the parison a is pressed against both outer surfaces of the pedestal part C3, both sides of the constricted body part C0, and the legs. A hollow made of synthetic resin that is integrally provided with a rod-shaped object B is pressed onto two surfaces of the molding groove connected to the edge of the leg base C2 while successively pressing them in a pinch-like manner over both outer surfaces of the base C2 as guide surfaces. A molded body A is molded.

Next, the mold is cooled to a certain temperature by the mold itself, the mold 3 is opened, and the molded product is taken out by fixing the end B1 of the rod-shaped material in a crimp-like manner with the elongated wall portion A1.

The material of the parison a is a thermoplastic synthetic resin material such as polyethylene or polypropylene.

Further, in the above method, the rod-shaped object end B1 and the vertical leg C may be bonded together in advance.

Therefore, it is suitable for molding a three-dimensional molded product A having the rod-shaped object B.

In addition, when the molded product A to be molded has a substantially -dimensional shape,
It is possible to freely open and close the upper and lower molds 1 and 3 from side to side.

In this case, the vertical leg C is temporarily fixed to the molding groove 2.

Next, the molded product A obtained by this method will be explained.

Fig. 5 shows a molded product A showing an example of a headrest for an automobile seat, and the molded product A has a predetermined hollow shape and has a rod-like end B1 fixed therein together with a vertical leg C in a crimp-like manner with an elongated wall portion A1. Thus, an integral structure is formed of the hollow molded body A, which is a hollow core, and the rod-shaped object B, which is a connecting rod to the seat.

The elongated wall portion A1 has a hooking portion A1o that is in close contact with the end B1 of the rod-like object, and a constricted hooking portion A01 that is in close contact with the vertical leg C, especially its body portion C1. Part C
1 and 1 form a triple beam part, and the end B1 of the rod-like object is fixed in a hollow position by swinging and deworming.

The vertical leg C is the core of the triple beam part, and the constricted body part C1 of the vertical leg C1 ensures biting engagement with the clamping part A, and the leg part C2 and the pedestal part C3 are connected to each other during molding. By controlling the movement of the vertical leg itself, the parison a is guided by the vertical leg C as a guide medium to ensure accurate shaping of the elongated wall portion A1.

Furthermore, the leg section C2 reinforces the rising base of the hook, and similarly, the pedestal section C3 reinforces the point where the hook meets the bar-like object end B1, thereby eliminating distortion at the rising base and the point where it reaches. .

As described above, the present invention places a vertical leg on the molding groove surface of one of the molds, places the end of the rod on the vertical leg, and then molds thermoplastic resin into a tube shape through a nozzle to form a parison. Pour into the molding groove, then fit the other mold together to encapsulate the parison only in the molding groove, and close only the tip of the parison with the overlapping surface of the mold in that part, and then squeeze compressed air into the parison. was injected into the end of the rod-shaped object and a portion of the parison located opposite these along the end of the rod-shaped object and the vertical leg surface, surrounding them in a crimp-like manner and fixing them. It is possible to form a molded product having a predetermined hollow shape having a rod-like object by being guided from the end of the object to the vertical legs and pinching and crimping them, and also pressing against the molding groove surface.

As a result, the rod-shaped object can be fixed and inserted into the hollow molded body apart from the inner wall surface thereof accurately and reliably, and various molded products can be molded integrally with the rod-shaped object.

Then, the molded product is held and fixed at the end of the rod by a triple beam part with an elongated wall part whose joint body is a core body.
The bond was robust.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the method of the present invention in the order of steps, and FIG. 1 is a cross-sectional view of a parison poured into a forming groove from a nozzle. FIG. 2 is a sectional view of the molded state. Fig. 3 is a cross-sectional view of the molding process with compressed air injected. FIG. 4 is an enlarged sectional view taken in the direction of the ■ arrow in FIG. FIG. 5 is a partially cutaway perspective view showing a molded product obtained by the method of the present invention. In the figure, A: hollow molded body, A1: elongated wall portion, B:
... Bar-shaped object, B1... End of bar-shaped object, C... Vertical leg, a.
... Parison, b... Compressed air, 1, 3... A pair of molds, 2... Molding groove of mold 1, 4... Molding mold 3
molding groove, 5... nozzle.

Claims (1)

[Claims] 1. Place a vertical leg on the molding groove surface of one of the molds, place the end of the rod on the vertical leg, and then mold thermoplastic resin into a tube shape through a nozzle to form a parison into the molding groove. Then, the other mold is put together to encapsulate the parison only in the molding groove, and only the tip of the parison is closed by the overlapping surface of the mold in that part, and then compressed air is injected into the squeezed parison. Insertion of a rod-like object into a synthetic resin hollow molded body in blow molding, which is characterized in that a part of the parison located along and opposite to the end of the rod-like object and the vertical leg surface is surrounded and fixed in a crimp-like manner and molded. How to wear it. 2 The end of a rod-shaped object vertically hollow inside a synthetic resin hollow molded body has a vertical leg that reaches the outer surface of the hollow molded body from the diametrical side surface thereof, and extends from at least the left and right walls separated by the vertical leg. A molded product that is fixed by an elongated wall portion that surrounds both side surfaces of the vertical leg and the substantially circumferential surface of the end of the rod-shaped object connected thereto and is clamped and crimped.