JP2016020061A - Blow molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blow molded product in which whether or not a built-in component is attached at a prescribed position of a blow molded product is easily determined in blow molding.SOLUTION: A blow molded product has an outer wall attaching part 17, to which a built-in component 20 is attached, on the inside of an outer wall 10. A plurality of attaching members 30 which are fused onto an inner surface of the outer wall 10 of the blow molded product and to which the built-in component 20 is attached are provided for the built-in component 20, and an abutting part 32 which abuts on the inner surface of the outer wall 10 of the blow molded product is formed on the attaching member 30. The abutting part 32 has an abutting surface 33 which faces an inner surface of the outer wall attaching part 17 of the blow molded product, and the abutting surface 33 is welded with the outer wall attaching part 17. An abutting recess 35 is formed on the abutting surface 33, the outer wall attaching part 17 of the blow molded product intrudes into the abutting recess 35, and an outer wall attaching part recess 18 is formed on an outer surface of the outer wall attaching part 17 of the intruded blow molded product.SELECTED DRAWING: Figure 9

Description

The present invention relates to a blow molded product made of a thermoplastic synthetic resin, and more particularly to a blow molded product having an outer wall formed by blow molding a thermoplastic synthetic resin member and having a built-in component inside.

For the production of hollow molded articles such as automobile fuel tanks made of thermoplastic synthetic resins, blow molding methods have been used in many cases because of the ease of molding hollow bodies. In the blow molding method, a parison of a molten thermoplastic synthetic resin member is formed into a cylindrical shape and extruded from above, the parison is sandwiched between molds, and air is blown into the parison to produce a blow molded product.

On the other hand, in the blow molding method, it may be necessary to attach a built-in part inside the blow molded product. For example, in a fuel tank for an automobile, a valve or a baffle plate for suppressing fuel flow noise may be used. There is a need to provide built-in components.
Therefore, the built-in parts are set on the resin frame, the resin frame is set in the mold, blow molded, and the resin frame is fixed to the inner peripheral surface of the outer wall of the fuel tank, and the built-in parts are placed inside the fuel tank. Some are attached (see, for example, Patent Document 1).

However, in this case, since the built-in parts are set on the resin frame and fixed to the inner peripheral surface of the outer wall of the fuel tank, it is necessary to remove the resin frame after molding. The weight may increase.

Moreover, in order to provide a built-in component inside a fuel tank, it may carry out as shown in FIGS. 17-18 (for example, refer patent document 2).
First, as shown in FIG. 17, before the parison 108 enters the blow molding die 140, the built-in component 120 is placed on the support bar 141, and the blow molding die 140 is opened and positioned therein. Thereafter, the parison 108 is lowered while the blow molding die 140 is kept open so that the built-in component 120 is positioned inside the parison 108.

Thereafter, as shown in FIG. 18, before closing the blow molding die 140, the pressing pins 142 are taken out from both sides of the blow molding die 140, the parison 108 is pressed, and the parison 108 is placed on the side end of the built-in component 120. Press. At this time, since the inner surface of the parison 108 is not yet solidified, the side ends of the parison 108 and the built-in component 120 can be fused.
Then, the support bar 141 is lowered, the blow molding die 140 is closed, and air is blown to perform blow molding.

In this case, the contact surface 133 that contacts the parison 108 formed at the tip of the built-in component 120 and the inner surface of the parison 108 are merely in contact, and the contact surface 133 does not enter the interior of the parison 108 and adhesion However, the fusion strength is not sufficiently high, and there is a risk of peeling due to vibration of the fuel or expansion of the fuel tank.

For this reason, as shown in FIG. 19, it is considered that a plurality of cylindrical contact pins 234 are formed on the contact surface 233 of the mounting member 230 of the built-in component (see, for example, Patent Document 3).
At this time, the pressing pin 242 of the blow molding die 240 presses the parison 208 at the time of blow molding, and the pressing pin 242 presses the contact pin 234 formed on the contact surface 233 of the mounting member 230, thereby making contact. The top portion 235 of the pin 234 enters the inside from the surface of the parison 208, the top portion 235 melts, and the parison 208 and the mounting member 230 are welded.

However, at this time, as shown in FIG. 20, the attachment member 230 determines whether or not the attachment member 230 is welded to a predetermined position of the outer wall attachment portion 217 of the parison 208 from the outside of the fuel tank after blow molding. It was difficult to judge.

JP-A-1-301227 JP-A-6-143396 JP 2009-132297 A

  Therefore, an object of the present invention is to provide a blow molded product that can easily determine whether a built-in component is attached to a predetermined position of the blow molded product during blow molding.

The present invention of claim 1 for solving the above-mentioned problem is a blow molded product which is formed by blow molding, has a built-in component attached therein, and has an outer wall formed of synthetic resin.
It has an outer wall mounting part to which a built-in part can be mounted inside the outer wall of the blow molded product,
The built-in component is provided with a plurality of mounting members that are fused to the inner surface of the outer wall of the blow molded product to mount the built-in component. The mounting member is formed with a contact portion that contacts the inner surface of the outer wall of the blow molded product. The contact portion has a contact surface facing the inner surface of the outer wall mounting portion of the blow molded product, and the contact surface is welded to the outer wall mounting portion,
A contact recess is formed on the contact surface, and the outer wall mounting portion of the blow molded product enters the contact recess, and an outer wall mounting portion recess is formed on the outer surface of the outer wall mounting portion of the blow molded product that has entered. It is a blow molded product.

According to the first aspect of the present invention, there is provided an outer wall mounting portion to which a built-in component is mounted inside the outer wall of the blow molded product, and the built-in component is attached to the inner surface of the outer wall of the blow molded product and attached to the built-in component. A plurality of members are provided. For this reason, the built-in components can be fused and fixed to the inner surface of the outer wall mounting portion of the blow molded product at a plurality of locations, and can be stably mounted.

Since the attachment member is formed with a contact portion that contacts the inner surface of the outer wall of the blow molded product, the contact member can be fused to the inner surface of the outer wall of the blow molded product to fix the attachment member. .
The contact portion has a contact surface facing the inner surface of the outer wall mounting portion of the blow molded product, the contact portion has a contact surface facing the inner surface of the outer wall of the blow molded product, and the contact surface is It is welded to the outer wall mounting part. For this reason, the contact surface of the mounting member and the inner surface of the outer wall of the blow molded product, which is a melted parison, are fused, and the mounting member can be firmly fixed to the outer wall of the blow molded product.

An abutting recess is formed on the abutting surface, and an outer wall mounting portion of the blow molded product enters the abutting recess, and an outer wall mounting portion recess is formed on the outer surface of the outer wall mounting portion of the blow molded product that has entered. For this reason, after blow molding, it is possible to easily determine whether or not the mounting member of the built-in component has been mounted at a predetermined position by checking the outer wall mounting portion recess on the outer surface of the blow molded product.

According to the second aspect of the present invention, the outer wall mounting portion is formed so as to protrude inward of the blow molded product, and the surface facing the contact surface of the mounting member of the protruding outer wall mounting portion is the contact surface. It is a blow molded product formed larger than the above.

According to the second aspect of the present invention, the outer wall mounting portion is formed so as to protrude inward of the blow molded product, and the surface facing the contact surface of the mounting member of the protruding outer wall mounting portion is the contact surface. Formed larger than. For this reason, while being able to attach an attachment member to an outer wall attachment part stably, the dispersion | variation in some dimensions of a built-in component and an attachment member can also be absorbed.

According to a third aspect of the present invention, the contact portion is a blow-molded product in which a plurality of contact pins or a plurality of protrusions protrude from the contact surface toward the inner surface of the outer wall of the fuel tank. It is.

In the present invention of claim 3, the contact portion is formed with a plurality of contact pins or a plurality of protrusions protruding from the contact surface toward the inner surface of the outer wall of the fuel tank. For this reason, a plurality of contact pins or a plurality of protrusions can penetrate into the outer wall of the blow molded product and be fused to firmly fix the mounting member to the outer wall of the blow molded product.

The present invention of claim 4 is a blow molded product in which the outer wall mounting portion recess is pressed by air pressure from a blow molding die.

In the present invention of claim 4, since the outer wall mounting portion recess is formed by being pressed by air pressure from the blow molding die, the parison strongly enters the contact recess during blow molding, and the outer wall mounting portion recess is reliably formed. Thus, the mounting position of the mounting member can be reliably confirmed, and the mounting member can be firmly mounted by reliably welding the outer wall mounting portion recess and the contact recess.

According to a fifth aspect of the present invention, the contact portion is a blow molded product in which an air vent hole penetrating from the contact surface to the inside is formed.

In the present invention of claim 5, since the air vent hole penetrating from the contact surface to the inside is formed in the contact portion, when the parison enters the contact recess during blow molding, the air in the contact recess is surely It can be removed, and the outer wall mounting portion concave portion and the contact concave portion can be brought into close contact with each other and welded to firmly attach the mounting member.

According to a sixth aspect of the present invention, the blow molded product is a fuel tank for automobiles, and the built-in component is a blow molded product having a baffle plate.

In the present invention of claim 6, since the blow molded product is a fuel tank for automobiles and the built-in component is a component having a baffle plate, a baffle plate for suppressing fuel flow noise inside the fuel tank. Built-in parts such as valves and valves can be securely attached at predetermined positions.

The contact portion has a contact surface facing the inner surface of the outer wall of the blow molded product, and the contact surface is welded to the outer wall mounting portion, so that the blow molding is a melted parison with the contact surface of the mounting member. The inner surface of the outer wall of the product is fused, and the mounting member can be firmly fixed to the outer wall of the blow molded product.
Since the contact recess is formed on the contact surface, and the outer wall mounting portion of the blow molded product enters the contact recess, and the outer wall mounting portion recess is formed on the outer surface of the outer wall mounting portion of the blow molded product that has entered, After blow molding, it is possible to easily determine whether or not the mounting member of the built-in component is attached at a predetermined position by checking the outer wall attachment portion recess on the outer surface of the blow molded product.

It is a fuel tank perspective view which is an embodiment of the invention. It is a partial expanded sectional view which shows the structure of the outer wall of the fuel tank of this invention. It is a perspective view of the built-in components attached to the inside of the fuel tank of the present invention. It is a top view of the attachment member of an embodiment of the invention. It is sectional drawing of the attachment member of embodiment of this invention, and is sectional drawing along the AA line of FIG. It is a bottom view of the attachment member of an embodiment of the invention. It is sectional drawing of the contact part of the attachment member of embodiment of this invention. It is sectional drawing of the state in which the part which comprises the outer wall attachment part of a parison was pressed by the contact part of the attachment member of embodiment of this invention. It is sectional drawing of the state in which the part which comprises the outer wall attachment part of a parison was pressed by the contact recessed part of the contact part of the attachment member of embodiment of this invention, and the outer wall attachment part recessed part was formed. The mounting member abuts on the outer wall mounting portion of the embodiment of the present invention with a slight displacement, and the portion constituting the outer wall mounting portion of the parison is pressed against the contact concave portion of the mounting member, and the outer wall mounting portion concave portion It is sectional drawing of the state formed. It is sectional drawing of the state in which the part which comprises the planar outer wall attachment part of a parison was pressed by the contact recessed part of the contact part of the attachment member of other embodiment of this invention, and the outer wall attachment part recessed part was formed. is there. The mounting member is slightly abutted against the planar outer wall mounting portion of another embodiment of the present invention, and the portion constituting the planar outer wall mounting portion of the parison is in the contact recess of the contacting portion of the mounting member. It is sectional drawing of the state pressed and the outer wall attaching part recessed part was formed. The cross section of the state in which the mounting member abuts on the outer wall mounting portion of the embodiment of the present invention with a large displacement, and an air hole is opened in a portion constituting the outer wall mounting portion of the parison in the contact recess of the mounting member contacting portion FIG. It is sectional drawing of the state which opened the blow molding die which shows the manufacturing method of the blow molded product of this invention. It is sectional drawing of the state which slid the press pin of the blow molding die which shows the manufacturing method of the blow molded product of this invention. It is sectional drawing of the state which closed the blow molding die which shows the manufacturing method of the blow molded product of this invention. It is sectional drawing of the state which opened the blow molding die which shows the manufacturing method of the conventional blow molded product. It is sectional drawing of the state which slid the press pin of the blow molding die which shows the conventional fuel tank manufacturing method. It is a top view of the conventional attachment member. It is sectional drawing of the process which attached the conventional attachment member to the parison.

An embodiment of the present invention will be described with reference to FIGS. 1 to 16 by taking an automobile fuel tank 1 which is a blow molded product as an example. In addition to the fuel tank 1 for automobiles, the present invention can be widely used when mounting a built-in component in a blow molded product.
In the embodiment of the present invention, as shown in FIG. 1, the fuel tank 1 has a pump unit mounting hole 4 formed on the upper surface so that a fuel pump (not shown) and the like can be taken in and out of the fuel tank 1. . A fuel injection hole 5 for injecting fuel from an inlet pipe (not shown) is formed on the side surface or the upper surface of the fuel tank 1.

An outer peripheral rib 2 is formed around the entire circumference of the fuel tank 1, and mounting holes 3 are formed at predetermined locations such as corner portions of the outer peripheral rib 2. The fuel tank 1 is attached to the vehicle body by bolting 3 and the vehicle body. It is also possible to attach a belt to the outer periphery of the fuel tank 1 instead of the attachment hole 3 and attach the fuel tank 1 to the vehicle body by the belt.
Furthermore, on the upper surface of the fuel tank 1, there are formed attachment holes 6 at various places for connecting a hose or the like for collecting the internal fuel vapor.

In the present embodiment, the fuel tank 1 is formed by blow molding, and its outer wall 10 has an outer skin layer 11, an outer body layer 12, an outer adhesive layer 13, and a barrier layer 14 in order from the outer side as shown in FIG. The inner adhesive layer 15 and the inner main body layer 16 are formed.
In blow molding, a parison composed of the above six layers is used. A parison having a layer structure of six layers or more can also be used. In addition, the skin layer 11 is used when a reproducing member, a filler, or the like is mixed in the external main body layer 12, but the skin layer 11 can be omitted. Further, if a material having rigidity and fuel oil resistance is used, a one-layer parison can be used.

The skin layer 11 and the outer main body layer 12 are formed of a thermoplastic synthetic resin that has high impact resistance and maintains rigidity against fuel oil, and is preferably formed of high-density polyethylene (HDPE).

Next, the built-in component 20 will be described with reference to FIG.
For example, a built-in component 20 shown in FIG. 3 is attached inside the fuel tank 1. A method for attaching the built-in component 20 will be described later.
The built-in component 20 is provided with a plurality of attachment members 30 that are fused to the inner surface of the outer wall of the fuel tank 1 to support the upper and lower sides. The attachment member 30 will be described later.

A contact portion 32 is attached to a tip portion of the attachment member 30 that contacts the inner surface of the outer wall 10 of the fuel tank 1. A contact surface 33 is formed on the upper surface of the contact portion 32. In the present embodiment, the contact portion 32 is formed integrally with the mounting member 30, but may be formed separately from the mounting member 30 at the tip of the mounting member 30.

The abutting portion 32 attached to the upper surface 21 of the built-in component 20 is welded to the inner surface of the parison 8 that forms the upper side wall of the outer wall 10 of the fuel tank 1 during blow molding, so that the built-in component 20 is placed inside the fuel tank 1. Can be installed. Further, the contact portion 32 of the mounting member 30 formed downward in the upper surface hole portion 24 of the built-in component 20 is welded to the bottom wall side of the outer wall 10.

The built-in component 20 can be formed of a fuel oil-resistant thermoplastic synthetic resin such as polyacetal or high-density polyethylene (HDPE). As a result, the strength of the fuel tank 1 can be improved, and even if the fuel tank 1 is attached to the inside of the fuel tank 1, the rigidity does not decrease due to swelling by the fuel oil or the like.

As shown in FIG. 3, the built-in component 20 of the present embodiment is formed in a ring shape having a space in the center and a continuous periphery in a substantially square shape. In addition, in this invention, the built-in component 20 which connected the column member with the beam member other than the form shown in FIG. 3 can also be used.

The ring-shaped portion of the built-in component 20 according to the present embodiment includes an upper surface 21 whose upper surface is formed on a substantially flat surface, an outer surface 22 that hangs from the upper surface 21 at a substantially right angle to the outer periphery, and a center from the upper surface 21. The inner surface 23 is formed in a shape formed of an inner surface 23 that hangs substantially perpendicular to the space side of the portion, and the interior surrounded by the upper surface 21, the outer surface 22, and the inner surface 23 is a hollow shape that does not have a lower side surface having a U-shaped cross section. Is formed. For this reason, the built-in component 20 can reduce the weight as a whole, contribute to weight reduction of the vehicle, and can be flexibly deformed. The upper surface 21, the outer surface 22, and the inner surface 23 are partially formed with a narrow width at the corner portion or short side of the fuel tank 1.

A plurality of mounting members 30 described above are formed on the upper surface 21, and a plurality of recessed upper surface hole portions 24 are formed. An attachment member 30 and a contact surface 33 can be formed on the bottom of the upper surface hole 24. As described above, the abutment surface 33 can be fused with the lower inner surface of the outer wall 10 to attach the built-in component 20 to the inside of the fuel tank 1. Thereby, even if the outer wall 10 of the fuel tank 1 expands or contracts due to a change in the internal pressure of the fuel tank 1, the outer wall 10 of the fuel tank 1 can be held.

The outer side surface 22 and the inner side surface 23 are formed long in the longitudinal direction on the long side of the built-in component 20. For this reason, since the outer side surface 22 and the inner side surface 23 are formed in a direction orthogonal to the moving direction of the fuel in the fuel tank 1 when the vehicle is running, the built-in component 20 can serve as a baffle plate. Even if the fuel in the fuel tank 1 moves or undulates during traveling by the outer side surface 22 and the inner side surface 23, excessive movement of the fuel is prevented and generation of the waving sound of the fuel oil in the fuel tank 1 is generated. Can be prevented and the occurrence of abnormal noise can be prevented.

The built-in component 20 is provided with a plurality of mounting members 30 to be described later for attaching the built-in component 20 by fusing to the inner surface of the outer wall 10 of the fuel tank 1. For this reason, the built-in component 20 can be fused and fixed to the inner surface of the outer wall 10 of the fuel tank 1 at a plurality of locations, and can be stably attached. Further, the present invention can also be used when a component other than the above is used as the built-in component 20.

Next, the attachment member 30 will be described with reference to FIGS.
The attachment member 30 may be formed integrally with the built-in component 20 or may be formed separately from the built-in component 20. In the present embodiment, an example in which the attachment member 30 is formed separately will be described.
As shown in FIGS. 3 to 6, the attachment member 30 may be formed in a cylindrical or rectangular tube shape, or may be formed in a flat plate shape.
In the present embodiment, the mounting member 30 is formed in a cylindrical tube shape, FIG. 4 is a plan view of the mounting member 30, FIG. 5 is a cross-sectional view of the mounting member 30, and FIG. 6 is a bottom view of the mounting member 30. It is.

The attachment member 30 is formed of an attachment member side wall 31 connected or continuous with the built-in component 20 and an abutment portion 32 that abuts against the inner surface of the outer wall 10 of the fuel tank 1. A contact surface 33 is formed on the upper surface of the contact portion 32. The attachment member 30 uses the same type of material as the material of the outer wall 10 in order to fuse with the outer wall 10 of the fuel tank 1. When the inner main body layer 16 of the fuel tank 1 is formed of high density polyethylene (HDPE), it is firmly welded.

In the present embodiment, the attachment member 30 is formed separately from the built-in component 20. In this case, the attachment member side wall 31 is formed in a cylindrical shape in accordance with the shape of the upper surface 21 of the built-in component 20, and the inside is hollow. A locking portion 38 is formed at the lower end of the attachment member side wall 31. When the attachment member side wall 31 is fitted into the tip of the upper surface 21 of the built-in component 20, the claw of the locking portion 38 is formed at the tip of the upper surface 21 of the built-in component 20 as shown in FIGS. The attachment member 30 is firmly attached by being engaged with the recess or the hole.

On the inner surface of the outer wall 10 of the fuel tank 1 opposed to the abutting surface 33 of the abutting portion 32, as shown in FIG. The surface of the outer wall mounting portion 17 that protrudes and faces the contact surface 33 of the mounting member 30 is formed larger than the contact surface 33. For this reason, even if the attachment member 30 is slightly displaced from the outer wall attachment portion 17, it can be stably attached to the outer wall attachment portion 17, and a slight variation in dimensions of the built-in component 20 and the attachment member 30 can also be absorbed. .

When the attachment member 30 is formed integrally with the built-in component 20, the attachment member side wall 31 is formed continuously with the upper surface 21.
As shown in FIG. 4, the contact portion 32 includes a circular contact surface 33 that faces the inner surface of the outer wall 10 of the fuel tank 1, and a plurality of protrusions that protrude from the contact surface 33 toward the outer wall 10 of the fuel tank 1. A contact pin 34 is formed. The contact pin 34 is formed in a circular column shape or a truncated cone shape having a circular or elliptical cross section. In the present embodiment, the contact pin 34 is formed in a cylindrical shape. The contact pin 34 may be formed in a truncated cone shape, or may be formed in an elliptic cylinder shape or a truncated cone shape having an elliptical cross section. Instead of the contact pin 34, a plurality of protrusions in a ring shape can be formed on the contact surface 33.

In this case, when the contact portion 32 is pressed against the inner surface of the outer wall 10 of the fuel tank 1, the contact pin 34 enters the outer wall 10 of the fuel tank 1, which is the parison 8, and the contact pin 34 and the contact pin 34 are in contact with each other. The outer wall 10 of the fuel tank 1 melted in between can enter, and the outer wall 10 of the fuel tank 1 and the contact surface 33 can be firmly fixed.

In the present embodiment, as shown in FIG. 4, the contact pin 34 is formed on substantially the entire surface of the contact surface 33 except for a contact recess 35 described later. Therefore, a large number of contact pins 34 can be formed on the contact surface 33, the outer wall 10 of the fuel tank 1 can be fused to the entire surface of the contact surface 33, and the outer wall 10 of the fuel tank 1 can be fused. It is possible to ensure the fusion strength.

As shown in FIG. 7, a contact recess 35 is formed in the center of the contact surface 33. An air vent hole 36 is formed at the center of the contact recess 35.
As shown in FIG. 8, at the time of blow molding, the outer wall is held on the contact surface 33 of the contact portion 32 and the contact recess 35 by being held by the pressing surface 42a of the pressing pin 42 of the blow molding die 40 to be described later. The parison 8 that forms the mounting portion 17 abuts.

Further, as shown by an arrow in FIG. 9, the parison 8 that forms the outer wall 10 by blowing air from the center hole 42 b of the pressing pin 42 of the blow molding die 40 described later to press the outer wall mounting portion 17 of the parison 8. Enters the contact recess 35. And the outer wall attaching part recessed part 18 is formed in the outer surface of the outer wall attaching part 17 which approached.

At this time, since the air vent hole 36 is provided, the air in the contact recess 35 is released, and the parison 8 can be in close contact with the contact recess 35. For this reason, it is possible to easily determine whether or not the mounting member 30 of the built-in component 20 is mounted at a predetermined position by checking the outer wall mounting portion recess 18 on the outer surface of the fuel tank 1 after blow molding.

That is, as shown in FIG. 10, when the attachment member 30 is attached to the outer wall attachment portion 17, the center of the outer wall attachment portion recess 18 (indicated by X in FIG. 10), that is, the center of the attachment member 30, and the outer wall attachment portion. When the center of 17 (indicated by Y in FIG. 10) is displaced, it can be easily determined that the attachment member 30 is displaced by the amount of the displacement.

As shown by the arrows in FIG. 11, even when the outer wall mounting portion 17 does not protrude from the outer wall 10 and is planar, air is blown from the center hole 42 b of the pressing pin 42 and the parison 8 is pressed. Similarly, since the outer wall mounting portion recess 18 is formed in the outer wall 10, the center of the outer wall mounting portion recess 18 (indicated by X in FIG. 12), that is, the center of the mounting member 30 and the center of the outer wall mounting portion 17 (see FIG. 12), it can be easily determined that the mounting member 30 is displaced from the predetermined position by the amount of the displacement.

Further, when the mounting member 30 is largely disengaged from the outer wall mounting portion 17, as shown in FIG. 13, the parison 8 forming the outer wall mounting portion 17 is broken by air pressure (indicated by an arrow in FIG. 13) during blow molding. Then, a hole is opened in the outer wall 10, and the deviation can be easily found.

Next, a method for manufacturing the fuel tank 1 of the present invention by blow molding will be described with reference to FIGS.
First, as shown in FIG. 14, the built-in component 20 is held by the support rod 41 and is positioned inside the blow molding die 40. Thereafter, the parison 8 is lowered and the built-in component 20 is positioned inside the parison 8.

Then, as shown in FIG. 15, the first pinch plate 43 is slid to hold the lower end of the parison 8 together with the support bar 41. At the same time, the plurality of pressing pins 42 provided on the blow molding die 40 are slid to press the parison 8 so as to be sandwiched between the mounting member 30 attached to the built-in component 20 and the pressing pins 42.

Then, since the inner surface of the parison 8 is still in a molten state, air is blown from the center hole 42 b of the pressing pin 42 as described above, and the parison 8 is inserted into the abutting recess 35 of the abutting portion 32 of the mounting member 30. The outer wall attaching portion recess 18 is formed in the outer wall attaching portion 17 of the outer wall 10.
Furthermore, the contact pin 34 of the contact portion 32 of the mounting member 30 can enter the inner surface of the parison 8, and the contact portion 32 and the parison 8 can be fused. At this time, since the built-in component 20 is held by the support rod 41, the attachment member 30 and the built-in component 20 can be reliably attached to a predetermined position on the outer wall 10 of the fuel tank 1.

After that, as shown in FIG. 16, the support bar 41 is lowered and removed from the blow molding die 40, the second pinch plate 44 is slid to close the parison 8, and the blow molding die 40 is closed, and the slide cutter At 46, the parison 8 is cut. When closing the blow molding die 40, the pressing pin 42 continues to press the parison 8 as it is. Thereby, the built-in component 20 can be kept in a predetermined position.

Then, air is blown into the inside of the parison 8 from the air nozzle 45, and the outer surface of the parison 8 is pressed against the blow molding die 40 to form the fuel tank 1. At this time, the front end surface of the pressing pin 42 and the cavity inner surface of the blow molding die 40 can be flush with each other.
Thereafter, the blow molding die 40 is opened and the fuel tank 1 is taken out.

DESCRIPTION OF SYMBOLS 1 Fuel tank 8 Parison 10 Outer wall 17 Outer wall attaching part 18 Outer wall attaching part recessed part 20 Built-in component 30 Attaching member 32 Abutting part 33 Abutting surface 34 Abutting pin 35 Abutting recessed part

Claims (6)

In blow molded products that are formed by blow molding, have internal parts attached inside, and have an outer wall formed of synthetic resin,
An outer wall mounting portion to which the built-in component is mounted inside the outer wall of the blow molded product;
The built-in component is provided with a plurality of mounting members that are fused to the inner surface of the outer wall of the blow-molded product to mount the built-in component, and the mounting member is in contact with the inner surface of the outer wall of the blow-molded product The corresponding contact portion has a contact surface facing the inner surface of the outer wall mounting portion of the blow molded product, and the corresponding contact surface is welded to the outer wall mounting portion,
A contact recess is formed on the contact surface, and the outer wall attachment portion of the blow molded product enters the contact recess, and an outer wall attachment recess is formed on the outer surface of the outer wall attachment portion of the blow molded product that has entered. A blow molded product characterized by this. The outer wall mounting portion is formed to protrude inside the blow molded product, and a surface of the protruding outer wall mounting portion that faces the contact surface of the mounting member is larger than the contact surface. The blow molded product according to claim 1 formed. 3. The contact portion according to claim 1, wherein a plurality of contact pins or a plurality of protrusions project from the contact surface toward the inner surface of the outer wall of the fuel tank. Blow molded product as described in 1. The blow molded article according to any one of claims 1 to 3, wherein the concave portion of the outer wall attachment portion is formed by being pressed by a pneumatic pressure from a blow molding die. The blow-molded product according to any one of claims 1 to 4, wherein the contact portion is formed with an air vent hole penetrating from the contact surface to the inside. The blow-molded product according to any one of claims 1 to 5, wherein the blow-molded product is a fuel tank for an automobile, and the built-in component is a component having a baffle plate.