JP3250013B2 - Blow molding hollow body fixing structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blow-molded hollow body constituting an electric device, a housing panel of furniture, an air-conditioning duct, an automobile part such as a console box, a carrying case, etc., in which a pocket, a bracket, a stay, a band and the like are formed. The present invention relates to a structure for fixing with a screw member.

[0002]

2. Description of the Related Art As a structure in which a screw member is used to fix another member to a blow-molded plastic hollow body, a tapping screw recess is formed in the wall surface of the plastic hollow body. A device in which a screw member is fixed to a tapping screw recess is described in Japanese Utility Model Laid-Open No. 2-122223.

[0003]

In the above-mentioned conventional plastic hollow body fixing structure, a recess for fixing a tapping screw is formed in the step of blow-molding the hollow body. As the resin is formed so as to dent the parison, the resin has a high degree of elongation at the base end of the dent that protrudes from the wall in the direction of the hollow part, and this part becomes thinner, and the fixing strength of the screw member decreases. There is.

[0004] The present invention is to solve the conventional disadvantages as described above, the screw fixation portion eliminate the decrease in adhesion strength due to thin-walled and to further improve the bonding strength together
If the part where the screw is screwed in is concave,
And extending thinly outwardly at least in the recess.
Form a concave groove that reaches almost the tip, and screw in
The part to be set corresponds to the slit groove or welding recess
If the hole is
Is formed to facilitate the screwing of screws.
It is an object of the present invention to provide a fixing structure for a hollow body .

[0005]

SUMMARY OF THE INVENTION The present invention is configured as follows to achieve the above object. The first configuration is
In a structure in which another member is fixed to a blow-molded plastic hollow body using a screw member, a recessed portion is formed in the wall surface of the plastic hollow body in the direction of the hollow portion. Extending outwardly and the recess
At least the groove is formed is reached substantially tip of a fixing structure of a blow-molded hollow body for fixing the screw member to the recess.

The second structure is a structure in which another member is fixed to a blow-molded plastic hollow body using a screw member, and a slit groove recessed in the hollow portion direction is formed on a wall surface of the plastic hollow body. A blow-molded hollow body fixing structure formed and fixed to a screw member in the slit groove.

The third structure is a structure in which another member is fixed to a blow-molded plastic hollow body by using a screw member. This is a blow-molded hollow body fixing structure in which a welded recess is formed by welding, a recess is formed in a portion of the opposite wall corresponding to the welded recess, and a screw member is fixed to the recess.

[0008]

According to the present invention, the wall surface of the hollow body of plastic, is formed a recess recessed in the hollow portion direction, and at least a thin extend and the recess outward by continuously provided in the recess
Or groove is reached at substantially the distal end portion is formed, or, since the slit grooves on the wall of the hollow body is formed, such as that forming the protruding recesses for fixing the screw member during the blow molding, the base end The elongation of the resin in the portion is not particularly increased, and the base end of the concave portion or the slit groove does not become thin. For this reason, the fixing strength of the screw member is increased. In addition, screw the screw
If the part to be fixed is a concave part, it is connected to this concave part and
A recess that extends narrowly and reaches at least a substantially leading end of the recess.
A groove is formed, and the part where the screw is screwed in is fixed.
If it is a hole corresponding to the slot or welding recess,
The groove is formed over the entire length in the screwing direction of
In this case, the screw can be easily screwed in, and in the case of the slit groove, since the fixing portion of the screw member extends over substantially the entire length, the arbitrariness of the fixing portion is increased. On one wall of the hollow body,
In the case where the welding recess is formed by being recessed in the direction of the hollow portion and welded to the opposed wall surface, the welding portion becomes thick, and the fixing strength for fixing the screw member to the welding portion is increased.

[0009]

An embodiment of the present invention will be described with reference to the drawings.

[0010] First Embodiment FIG. 1 and FIG. 2, 5 and 6, there is shown a first embodiment of the present invention. 1 and 2, reference numeral 1 denotes a plastic hollow body, and the hollow body 1 is obtained by blow molding a thermoplastic resin. The hollow body 1 is made of polyethylene, polypropylene, ABS resin, polyamide,
It is composed of a rigid thermoplastic such as styrene-modified polyphenylene oxide or polycarbonate. On the wall surface 2 of the hollow body 1, there is formed an annular recess 4 slightly smaller than the crest diameter of the screw member recessed in the direction of the hollow portion 3 . Show
In Suyo, extending narrow in its outward and less of the recess 4
Both are formed by consecutively concave groove 5 is reached in a substantially distal portion in three directions radially. The width of the portion of the concave groove 5 connected to the concave portion 4 is formed smaller than the diameter of the annular concave portion 4. Reference numeral 6 denotes another wall surface of the hollow body 1, which is integrally formed with the recess 4 during blow molding.
Is welded. Reference numeral 7 denotes a bracket, and the bracket 7 is an example of another member fixed to the plastic hollow body 1. The bracket 7 is configured such that the screw member 8 is connected to the recess 4 of the hollow body 1.
By being screwed into the fixing member as shown in FIG.
The screw member 8 is a self-tapping screw.

FIG. 3 shows a blow molding mode of the hollow body 1 shown in FIG. 1 and FIG. FIG. 4 shows a conventional blow molding mode corresponding to FIG. 9,1
Reference numeral 0 denotes a split die, 9A denotes a slide die, and 11 denotes a parison. One split die 9 has a bulged cavity 12 for forming the concave portion 4 and the concave groove 5. The cavity 12 is composed of a projection 13 forming the concave portion 4 and an inclined portion 14 whose width increases from the distal end to the base end. The inclined portion 14 is for forming the concave groove 5. As shown in FIG. 3, when the parison 11 is arranged between the split molds 9 and 10 and the split molds 9 and 10 are closed, the parison 11 is deformed as shown by a virtual line in FIG. 3. In this step, the resin around the concave portion 4 formed by the projection 13 is deformed while being supported by the inclined portion 14, so that if the degree of elongation of the resin at the base end portion that finally forms the concave portion 4 is high, Without
The portion does not become thin and the paris 11 does not tear. In addition, as shown by a virtual line, Paris 1
After molding 1, the slide die 9A is retracted to take out a molded product, and the molding is completed. In the conventional device shown in FIG. 4, the cavity 12 forming the recess 4 is simply a protrusion 13, and therefore, as shown by a virtual line, the elongation of the resin at the base end portion a of the recess 4 is particularly high, The portion becomes thin and the strength is reduced, and the parison 11 is apt to be torn, resulting in a high defective molding rate.

FIGS. 5 and 6 show modifications of the first embodiment. FIG. 5 shows an example in which the concave groove 5 is formed radially in four directions of the concave portion 4, and the distal end portion 5A of the concave groove 5 does not reach the distal end portion 4A of the concave portion 4 . So that at least a substantially distal end of the recess 4
It has reached 4A . FIG. 6 shows an example in which the concave grooves 5 are formed in two directions of the concave portion 4, and the concave grooves 5 in the two directions form substantially slit grooves. When the short screw member 8 is fixed to the recess 4, the recess 4 does not necessarily have to be a structure welded to the other wall surface 6, as shown in FIG. The length may be such that the screw member 8 penetrates the portion. The screw member 8 is a self-tapping screw, a wood screw, or a mounting member having a threaded end.

Second Embodiment FIGS. 7 to 10 show a second embodiment of the present invention. In this second embodiment,
Except that the slit groove 15 is formed in the wall surface 2 of the hollow body 1, it has the same configuration as that of the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted. The slit groove 15 is formed on the wall 2
Is formed in the hollow part 3 in the direction from
Is welded to. The slit groove 15 is formed to have a width suitable for fixing the screw member 8, that is, a width slightly smaller than the maximum mountain diameter of the screw member 8. Slit groove 15
Does not necessarily have to be welded to the other wall surface 6.

The second embodiment is blow-molded as shown in FIG. That is, when the parison 11 is arranged between the split molds 9 and 10 and the split molds 9 and 10 are closed,
The parison 11 is formed as shown by a virtual line in FIG.
In this step, since the slit groove 15 is formed by the long plate-shaped protrusion 16, the resin in the portion of the slit groove 15 does not partially have a high degree of elongation, and the slit groove 15 It does not become thin and the paris 11 does not tear. The basic forming method is the same as in the first embodiment.

In the second embodiment, the screw member 8 is fixed to the slit groove 15 as shown in FIG. As shown in this figure, the screw member 8 is provided with the slit groove 1.
5 and a large number thereof can be fixed at an arbitrary position over substantially the entire length. Further, even with the screw member 8A having a large crest diameter, since the resin wall exists in the direction of the slit groove 15, the fixing strength is maintained by the wall thickness t.

Third Embodiment FIG. 11 and FIG.
A third embodiment of the present invention is shown. The third embodiment is similar to the first embodiment except that a slit-shaped groove 17 is formed on one wall surface 2 of the hollow body 1 and the slit groove 17 is welded and integrated with the other wall surface 6. And the same components are denoted by the same reference numerals and description thereof will be omitted. In the third embodiment, a hole 19 is formed corresponding to the welded portion 18 of the slit-shaped concave groove 17 on the other wall surface 6, and the screw member 8 is fixed to the hole 19. Groove 1 on other wall 6
The welded portion 18 of 7 becomes thick.

In the third embodiment, the concave groove 17 does not have to have a slit shape, but has a structure in which a concave portion of one wall surface 2 is welded to the other wall surface 6. Any other configuration may be used as long as a hole 19 is formed in the other wall surface 6.

FIG. 13 illustrates a housing 20 of an electric control device using the hollow body 1 according to the second embodiment as a door. In the figure, each device unit 21 and bracket 22
Are fixed to the slit grooves 15 by a plurality of screw members 8, respectively. 23 is a code.

[0019]

According to the first, second and third inventions according to the present invention, a decrease in the fixing strength caused by the thinned portion of the screw fixing part is eliminated, and the fixing strength is further improved. Can be. And, as in the first invention,
If the part to be screwed in is a concave,
At least approximately at the tip of the recess.
Forming a concave groove reaching the second invention or the third invention.
As shown, the part where the screw is screwed in and fixed
How to screw in the hole in the part corresponding to the welding recess
Since the groove is formed over the entire length of the screw,
Easy screwing. In particular, according to the second and third inventions according to the present invention, it is possible to greatly improve the arbitrariness of the fixing portion together with the improvement of the fixing strength. Therefore, when the conventional self-tapping screw is used, it is necessary to fix the same part again to the same place in terms of strength. However, according to the present invention, the position in the vicinity thereof can be shifted to fix the part again.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a part of a blow-molded hollow body showing a first embodiment according to the present invention.

FIG. 2 is an enlarged sectional view taken along line AA in FIG.

FIG. 3 is a schematic sectional view showing a blow molding mode of the one shown in FIGS. 1 and 2;

FIG. 4 is a schematic sectional view showing a conventional blow molding mode corresponding to FIG.

FIG. 5 is a partial perspective view showing a modification of the first embodiment according to the present invention.

FIG. 6 is a partial perspective view showing another modification of the first embodiment according to the present invention.

FIG. 7 is an exploded perspective view of a part of a blow-molded hollow body showing a second embodiment according to the present invention.

FIG. 8 is an enlarged sectional view taken along line BB in FIG. 1;

FIG. 9 is a schematic sectional view showing a blow molding mode of the one shown in FIGS. 7 and 8;

FIG. 10 is a partial front view of the second embodiment according to the present invention.

FIG. 11 is an exploded perspective view of a part of a blow-molded hollow body showing a third embodiment according to the present invention.

FIG. 12 is an enlarged sectional view taken along line C- in FIG. 11;

FIG. 13 is an overall perspective view of an electric control device using a blow-molded hollow body according to a second embodiment of the present invention.

[Description of Signs] 1 hollow body 2 wall surface 3 hollow portion 4 concave portion 5 concave groove 6 other wall surface 7 bracket 8 screw member 9,10 split mold 11 parison 12 cavity 13 protruding portion 14 inclined portion 15 slit concave groove 16 long plate shape Projecting portion 17 Slit-shaped concave groove 18 Welding portion 19 Hole

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 49/00-49/80 B29C 65/56-65/64

Claims (3)

(57) [Claims] In a structure in which another member is fixed to a blow-molded plastic hollow body using a screw member, a recessed portion is formed in the wall surface of the plastic hollow body in the direction of the hollow portion. anchoring structures blow molding hollow bodies narrow extending and forming a concave groove that at least reaches a substantially distal portion of the recess outwardly continuously provided, characterized by fixing the screw member to the recess. 2. A structure in which another member is fixed to a blow-molded plastic hollow body using a screw member, wherein a slit groove is formed in a wall surface of the plastic hollow body in a direction of the hollow portion. A structure for fixing a blow-molded hollow body, wherein a screw member is fixed to the groove. 3. A structure in which another member is fixed to a blow-molded plastic hollow body using a screw member, wherein a welding recess is formed in the wall surface of the plastic hollow body so as to be recessed in the direction of the hollow portion and welded to an opposite wall surface. Wherein a hole is formed in a portion of the opposed wall corresponding to the welding concave portion, and a screw member is fixed to the hole.