JPH06218799A - Manufacture of housing panel - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a method of manufacturing a housing panel capable of excellently molding a female screw integrally with a housing panel formed by blow molding of a thermoplastic synthetic resin. A method of manufacturing a hollow body-shaped housing panel 16 by blow molding a thermoplastic synthetic resin. In one cavity 2 of the blow molding die 1, a movable member 4 having an internal thread forming part 5 at the tip and having an air escape hole 7 in an air escape groove 6 of the internal thread forming part 5 is projected to make a parison 11. Blow molding. Next, the movable member 4 is rotated and separated from the female screw portion 13 to obtain the housing panel 16 in which the female screw portion 13 is formed on one wall of the housing panel 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a housing panel which constitutes a housing of a copying machine, a computer, an air conditioner, a control device or the like.

[0002]

2. Description of the Related Art In a housing of a copying machine, a computer, an air conditioner, a control device, etc., various parts and accessories are attached to a housing panel constituting the housing (for example, Japanese Patent Laid-Open No. 61-61). 79295 and Japanese Utility Model Laid-Open No. 2-128997).

In the above-mentioned Japanese Patent Laid-Open Publication No. 61-79295, various components and the like are exposed on the surface of the housing panel, and the appearance of the housing is inferior. Kaihei 2-12
What is described in Japanese Patent No. 8997 is very excellent in terms of recycling of resin because the mounting portion is not exposed on the surface of the panel and the metal nut is not embedded in the mounting portion of the panel.

[0004]

However, in the one disclosed in Japanese Utility Model Laid-Open No. 2-128997, a recess is formed in one wall of a housing panel formed by blow molding of a thermoplastic synthetic resin. Then, since parts etc. are attached to this recess with self-tapping screws,
There is a problem that the self-tapping screw has a low tightening strength because it is difficult to attach parts and the like and it is difficult to form a thick recess by blow molding. Further, instead of the recess for self-tapping screw described in Japanese Utility Model Publication No. 2-128997, it is conceivable to integrally form an internal thread at the time of blow molding, but a spiral of a mold for integrally forming an internal thread by blow molding. Since the groove is extremely narrow, the resin does not enter sufficiently, which causes defective molding of the crest of the female screw, resulting in a decrease in mounting strength (see FIG. 4). In FIG. 4, a is a blow molding die, b is a movable member having a female screw molding portion c at its tip, and d is a spiral groove. e is a parison, f is a formed female screw portion, and g is a mountain portion thereof.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, in which a female screw is favorably integrally formed with a housing panel formed by blow molding of a thermoplastic synthetic resin to form various parts and accessories. An object of the present invention is to provide a method for manufacturing a housing panel, which can improve the mounting operability of a product or the like with screws and can improve the mounting strength.

[0006]

Means according to the present invention for achieving the above object are as follows. That is, in a method for manufacturing a hollow body-shaped housing panel by blow molding a thermoplastic synthetic resin, one cavity of a pair of blow molding dies has a female screw molding portion at its tip and a female screw molding portion. A parison is blow-molded by projecting a movable member provided with an air escape means in the spiral groove of, and then the movable member is rotated to separate from the female screw portion formed in the housing panel, and one wall of the housing panel It is a method of manufacturing a housing panel in which a female screw portion is formed on the.

[0007]

In the method of manufacturing a housing panel according to the present invention, the movable member is projected into one of the cavities of a pair of blow molds for blow molding the housing panel, the parison is blow molded in that state, and then the movable member is blown. Since it is rotated to separate it, one wall of the blow-molded housing panel is integrally formed with a female screw portion corresponding to the shape of the spiral female screw molded portion at the tip of the movable member. Since the movable member is provided with air escape means such as a groove or a hole in the spiral groove, the air present between the spiral groove of the movable member and the resin during blow molding is accompanied by the movement of the resin. When the resin escapes and the resin is completely along the spiral groove of the movable member, the female screw portion is well formed.

[0008]

1 to 3, reference numerals 1 and 1 designate a pair of blow molding dies, and the blow dies 1 and 1 are of a split type. 2 and 2 are the cavities. The movable member 4 is attached to each of the plurality of movable member fitting portions 3 in the cavity 2 of the one mold 1. The movable member 4 has a spiral groove-shaped female screw forming portion 5 at the tip thereof, and a large number of air escape holes 7 are opened in the spiral groove 6 of the female screw forming portion 5, and these air escape holes 7 are formed. The escape hole 7 communicates with an air passage 8 passing through the axis of the movable member 4 and communicates with the outside air. The air escape hole 7 may be formed in a groove shape. The movable member 4 is movable in its axial direction,
And it is rotatable. On the mold 2 on which the movable member 4 is mounted, an annular convex portion 9 is formed in the cavity 2 so as to surround the movable member 4.

Next, a method of manufacturing the housing panel according to the present invention will be described in the order of steps. First, mold 1,1
The parison 11 extruded from the extruding head 10 is arranged in the opened state. Next, the molds 1 and 1 are closed, and after the parison is made to substantially follow the shape of the cavities 2 and 2 by means such as pre-blowing, the movable member 4 is moved to a position where the female screw molding 5 projects into the cavity 2. Then, if the parison 11 is blow-molded, the cylindrical wall portion 12 is formed along the female screw forming portion 5 of the movable member 4 protruding into the cavity 2, and the female screw portion 13 is formed on the inner peripheral surface thereof. Molded. A welded weld portion 14 welded to the other wall is formed at the tip of the cylindrical wall portion 12, and the female screw portion 13 is integrated over the other wall. In addition, a reinforcing portion 15 in which the parison 11 is raised by the annular convex portion 9 is formed around the cylindrical wall portion 12. Reference numeral 16 denotes a molded housing panel. After the blow molding, the movable member 4 is rotated so as to be retracted and separated in the direction in which the cylindrical wall portion 12 is pulled out from the female screw portion 13 formed therein, the molds 1 and 1 are opened, and the molded housing panel 16 is formed. To remove the excess burr. The housing panel 16 is made of ABS resin,
It is made of blow-moldable hard thermoplastic resin such as styrene-modified polyphenylene oxide resin, polyamide resin, polycarbonate resin, and polypropylene resin.
The housing panel may be used as a furniture housing such as a cabinet other than electronic equipment.

In the blow molding process, the movable member 4
The female screw forming portion 5 is formed with an air escape groove 6 below the valley portion thereof, and an air escape hole 7 is provided in a part of the air escape groove 6, and the air escape hole 7 is provided with an air passage 8 Therefore, the air present between the parison 11 and the female screw forming part 5 escapes to the outside air from the air escape hole 7 through the air passage 8 as the parison 11 enters the air escape groove 6. The air pressure between the female screw forming part 5 and the parison 11 does not rise. For this reason, the parison 11 is correctly inserted along the spiral female screw forming portion 5, and the female screw portion 13 is well formed. In the blow molding process, if the air is sucked from the air passage 8, the parison 11 can be quickly and surely inserted into the air escape groove 6, and the molding mode of the female screw portion 13 is further improved. In this embodiment, the air escape groove 6 or the air escape hole 7 constitutes an air escape means. On the other hand, in the conventional forming means shown in FIG. 4, since there is no air escape means in the spiral groove d of the female screw forming part c of the movable member b, there is an interposition between the parison e and the spiral groove d during blow molding. As a result, the air pressure is increased, the parison e does not enter the valley of the spiral groove d, and defective molding easily occurs in the crest portion of the female screw portion f.

In FIG. 5, another member 17 and a screw member 18 are attached to the housing panel 16 manufactured by the method according to the present invention.
Is shown attached. As shown in FIG. 5, in this mounting mode, the cylindrical wall portion 12 of the housing panel 16 extends integrally from the inner wall 19 and is integrally welded to the outer wall 20 by the welding weld portion 14, and the base portion of the cylindrical wall portion 12 is raised. Since it is reinforced by the raised reinforcing portion 15, the strength of the cylindrical wall portion 12 having the female screw portion 13 is large, and the female screw portion 13 of the cylindrical wall portion 12 is well molded as described above. The attachment strength of the other member 17 by the screw member 18 is also large. Reference numeral 21 is a gap between the cylindrical wall portion 12 and the tip of the screw member 18, and reference numeral 22 is a hollow portion of the housing panel 16.
Further, since the female screw 13 is favorably integrally formed on the cylindrical wall portion 12 of the housing panel 16, it is not necessary to cut a self-tapping screw when the other member 17 is attached by the screw member 18, and the screw of the screw member 18 is not necessary. The wearing operation can be performed smoothly and easily.

FIG. 6 illustrates a control device 24 in which an opening / closing door 23 is formed of a housing panel 16 manufactured by the method according to the present invention. In this control device 24,
The device unit 25 is attached to the inner wall 19 of the opening / closing door 23 with a plurality of screw members 18 as shown in detail in FIG. 5, and the fixing member 27 of the cords 26 is also attached with the screw members 18. There is.

As shown in FIG. 5, the cylindrical wall portion 12 formed on the housing panel 16 is welded to the front wall 20 by a welded weld portion 14, which welded weld portion 14 is formed during blow molding. Therefore, the trace does not appear on the surface of the front wall 20. It should be noted that foreign substances such as metal nuts are not embedded in the housing panel 16, so that it is possible to easily reuse the resin when molding defects occur or to reuse the resin by waste treatment.

[0014]

According to the present invention, a female screw is favorably integrally formed on a housing panel formed by blow molding of a thermoplastic synthetic resin to improve the operability of mounting various parts and accessories with screws. In addition, it is possible to obtain the housing panel that can improve the mounting strength.

[Brief description of drawings]

FIG. 1 is a side view showing a blow molding aspect of a housing panel according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a partially enlarged sectional view of FIG.

FIG. 4 is a partial vertical cross-sectional view showing a conventional blow molding mode.

FIG. 5 is a partial cross-sectional view showing an aspect in which another member is attached to the housing panel manufactured by the method according to the present invention.

FIG. 6 is an overall perspective view of a control device in which an opening / closing door is composed of a housing panel manufactured by the method according to the present invention.

[Explanation of symbols]

 1, 1 Blow Molding Die 2, 2 Cavity 3 Movable Member Fitting Part 4 Movable Member 5 Female Thread Molding Part 6 Air Escape Groove 7 Air Escape Hole 8 Air Passage 9 Annular Convex 10 Extrusion Head 11 Paris 12 Cylinder Wall 13 Female screw part 14 Weld weld part 15 Reinforcement part 16 Housing panel 17 Other member 18 Screw member 19 Inner wall 20 Outer wall

Claims (1)

[Claims] 1. A method for manufacturing a hollow body-shaped housing panel by blow molding a thermoplastic synthetic resin, wherein one cavity of a pair of blow molding dies has a female thread molding portion at its tip, and a female thread molding portion is formed. The movable member provided with air escape means is projected in the spiral groove of the screw forming portion to blow-mold the parison, and then the movable member is rotated to separate from the female screw portion formed on the housing panel, and the A method for manufacturing a housing panel, comprising forming a female screw portion on one wall.