JP2006188074A - Insert blow-molding method of panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To save an excessive process of boring a blow-molded article and press-fitting a reinforcing pipe carried out in the prior art to attach the reinforcing pipe on a panel. <P>SOLUTION: The method of blow-molding by inserting the reinforcing pipe comprises the steps of fixing the reinforcing pipe to a magnet protruding from the cavity in the mold toward the inside by magnetism of the magnet, clamping the parison, and blowing air into the parison to carry out the insert-molding of the reinforcing pipe. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a method for blow molding by inserting a reinforcement tube into a panel.

Conventionally, in order to mount a lean force pipe on a panel, a hole is made in the panel molded product body after blow molding by a drill or the like, and the lean force pipe is press-fitted.
JP 11-156926 A

However, since an extra step of drilling and press-fitting is required after blow molding, there is a disadvantage that the cost is increased.

The problem to be solved is that it is not possible to omit an extra step of drilling a molded product after blow molding and press-fitting a lean force pipe.

In the present invention, a lean force pipe is fixed to a magnet projecting inward from the cavity surface in the mold by the magnetic force of the magnet, and then the parison is clamped and air is blown into the parison. The main feature is to insert-mold the lean force pipe.

According to the molding method of the present invention, since the insertion of the lean force pipe is completed at the same time as the blow molding is completed, the advantage that an extra step of punching the molded product after blow molding and press fitting of the lean force pipe is not required. There is.

The objective of manufacturing an inexpensive panel with a lean force pipe was realized by insert blow molding the lean force pipe using a magnet-attached mold without impairing the strength of the panel.

FIG. 1 shows an automotive panel 9 according to the invention. Reference numeral 1 denotes a steel lean force pipe. FIG. 2 is a longitudinal sectional view of a mold at the time of blow molding. 7 is an extruder head of a blow molding machine (not shown), 8 is a die, and 2 is a plurality of protrusions protruding from the cavity surface 6 in the mold to the inside of the cavity surface 6 in a direction perpendicular to the surface. It is a magnet. As shown in FIG. 2, the steel lean force pipe 1 is fixed by the magnetic force of the magnet 2 mounted on the mold 3. The material of the steel lean force pipe is not limited to steel, and any material may be used as long as it contains iron, nickel, cobalt and other ferromagnetic materials.

Next, the operation of the present invention will be described with reference to FIGS. 3 to 6 are cross-sectional views showing the states of the respective stages of blow molding according to the present invention. First, a resin parison 4 such as polypropylene is extruded into the mold 3 to which the steel lean force pipe 1 is fixed in advance by the magnet 2 and then the mold is clamped.

The resin is not limited to polypropylene, and may be any resin that can be blow-molded, such as other general-purpose resins and engineering plastics, and composite materials obtained by kneading materials other than resins. The state of the parison after clamping is as shown in 4 of FIG. By blowing air into the parison 4, the parison 4 is deformed so as to surround the steel lean force pipe 1 as shown in FIG.

Thereafter, when the air is blown to the end, the magnet 2 protrudes inward from the cavity surface 6 in the mold in the direction perpendicular to the surface, so that the parison 4 is made of the steel lean as shown in FIG. The force pipe 1 is completely enclosed, and both are in close contact with each other.

Thereafter, when the mold 3 is opened, the insert blow molding of the panel with the steel lean force pipe is completed as shown in FIG.

In this case, since the magnet 2 protrudes inward from the cavity surface 6 in the mold in the direction perpendicular to the surface, the trace of the magnet 2 being left is left as a cavity 5. If the hollow 5 is pulled out by the air cylinder (not shown) or the hydraulic cylinder (not shown) before the completion of the blowing, the cavity 5 is filled and disappears by the subsequent deformation of the parison 4, so that the appearance of the molded product is improved and the merchantability is increased. Is up.

The panel with a steel lean force pipe according to the present invention can be used for a rear luggage compartment of an automobile or a general table.

The perspective view of the panel by this invention Mold longitudinal section during blow molding according to the present invention Cross section showing the first stage of blow molding of the present invention Cross section showing the second stage of blow molding of the present invention Cross section showing the third stage of blow molding of the present invention Cross section showing the fourth stage of blow molding of the present invention

Explanation of symbols

1 Steel Reinforce Pipe 2 Magnet 3 Mold 4 Parison 5 Cavity 6 Cavity Surface in Mold 7 Extruder Head 8 Die 9 Automotive Panel

Claims (2)

A lean force pipe is fixed to the plurality of magnets protruding from the cavity surface in the mold to the inside of the cavity surface in the mold by the magnetic force of the magnet, and then the parison is clamped, An insert blow molding method for a panel, characterized in that the lean force pipe is insert molded by blowing air into the panel. 2. The magnet according to claim 1, wherein a magnet projecting from the cavity surface in the mold and projecting to the inside of the cavity surface in the mold is pulled out by an air cylinder or a hydraulic cylinder before the completion of blowing. Panel insert blow molding method