JP2016128277A - Fitting structure of integrated component of automobile fuel tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel tank in which an integrated component, which has high rigidity and is easily manufactured, can be fitted inside the fuel tank.SOLUTION: In a fitting structure of an integrated component 20 of an automobile fuel tank 1 to which the integrated component 20 is fitted inside and which has an outer wall made of a synthetic resin, the integrated component 20 comprises: an upper contact part 21 and a lower contact part 22 in which the integrated component 20 is fused and fitted to upper and lower inner surfaces of a tank outer wall 10 of a fuel tank 1; and a body part 23 connecting the upper contact part 21 and the lower contact part 22. The upper contact part 21 and the lower contact part 22 have an upper welding surface 21a and a lower welding surface 22a welded to the inner surface of the tank outer wall 10, respectively. Outer wall inner surface projection parts 18 projecting to the inside of the fuel tank are formed on the tank outer wall 10. Planar outer wall inner surface welding surfaces 17 are formed on surfaces of the outer wall inner surface projection parts 18, which face the upper welding surface 21a and the lower welding surface 22a.SELECTED DRAWING: Figure 6

Description

The present invention relates to a structure for mounting a built-in component of a fuel tank made of a thermoplastic synthetic resin, and in particular, a fuel tank having a built-in component inside with an outer wall formed by blow molding a thermoplastic synthetic resin member. The present invention relates to a built-in component mounting structure.

Conventionally, the structure of fuel tanks for automobiles and the like has been made of metal, but in recent years, thermoplasticity has been achieved by reducing the weight of the vehicle, eliminating rust, and easily forming into a desired shape. Those made of synthetic resin have come to be used.
In the production of an automotive fuel tank made of a thermoplastic synthetic resin, a blow molding method has been often used because of the ease of molding a hollow body. In the blow molding method, a parison of a molten thermoplastic synthetic resin member is formed into a cylindrical shape and extruded from above, and the parison is sandwiched between molds and air is blown into the parison to manufacture an automobile fuel tank.

On the other hand, in the blow molding method, it is required to provide a built-in component having other functions in order to improve the rigidity of the outer wall of the tank inside the fuel tank.
In some cases, the built-in components are provided inside the fuel tank as shown in FIGS. 24 to 25 (see, for example, Patent Document 1).
First, as shown in FIG. 24, 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. 25, 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 attachment member welding surface 133 that contacts the parison 108 formed at the front end of the built-in component 120 is merely in contact with the inner surface of the parison 108, and the attachment member welding surface 133 does not enter the inside of the parison 108. The adhesiveness was weak and the fusion strength was not sufficiently high, and there was a risk of peeling due to vibration of the fuel or expansion of the fuel tank.

Therefore, as shown in FIG. 26, a plurality of column-shaped contact pins 234 are formed on the attachment member welding surface 233 of the attachment member 230 having the cylindrical side wall 231 of the built-in component, and as shown in FIG. One that is pressed against and welded to the inner surface of 208 is considered (for example, see Patent Document 2).
At this time, it is necessary to increase the attachment member welding area between the attachment member welding surface 233 and the parison 208 so that the stress applied to the attachment member 230 of the built-in component is reduced in consideration of the low temperature impact property. .

Further, in order to secure the welding strength between the mounting member 230 and the parison 208, when the mounting member welding surface 233 is strongly pressed against the parison 208, as shown in FIG. 27, the notch 209 that is a molten resin protrudes from the parison 208. Formed as follows. In this case, when an impact is applied to the welded portion of the mounting member 230, the stress concentrates on the notch 209, and there is a possibility that the outer wall of the fuel tank is stressed.

Therefore, as shown in FIG. 28, there are some which make the attachment member welding surface 333 of the attachment member 330 larger than the outer wall protrusion 318 of the fuel tank 310.
However, in this case, as shown in FIG. 29, since the attachment member 330 has rigidity, the attachment member 330 is formed in a cylindrical shape, and a shock absorbing hole 331 is provided in the cylindrical attachment member 330 to absorb the impact. . For this reason, it takes time and labor to form the upper surface of the attachment member welding surface 333 of the cylindrical attachment member 330 and the shock absorbing hole 331, and the cost is increased.

JP-A-6-143396 JP 2013-060096 A

  Therefore, an object of the present invention is to provide a fuel tank in which a built-in component having high rigidity and easy manufacture can be mounted at a predetermined position in the fuel tank.

The present invention of claim 1 for solving the above-mentioned problem is a mounting structure for a built-in component of an automotive fuel tank having a built-in component mounted inside and having an outer wall formed of a synthetic resin.
The built-in parts have upper and lower abutting parts that are fused to the upper and lower inner surfaces of the tank outer wall of the fuel tank, and a main body part that connects the upper and lower abutting parts. And
The upper contact portion and the lower contact portion each have an upper weld surface and a lower weld surface that are welded to the inner surface of the tank outer wall,
The outer wall of the tank is formed with an outer wall inner surface protruding portion that protrudes to the inside of the fuel tank, and a flat outer wall inner surface is formed on the surface facing the upper and lower welding surfaces of the outer wall inner surface protruding portion. It is the attachment structure of the built-in components of the fuel tank for vehicles.

According to the first aspect of the present invention, in the mounting structure for a built-in component of an automobile fuel tank having a tank outer wall formed with a synthetic resin and having a built-in component attached to the inside, the built-in component is provided on the upper and lower inner surfaces of the tank outer wall. An upper contact portion and a lower contact portion for attaching a built-in component by fusing, and a main body portion for connecting the upper contact portion and the lower contact portion. Therefore, the upper and lower contact portions support the upper and lower portions of the tank outer wall, and the main body portion can absorb the impact of the tank outer wall and prevent excessive expansion and contraction.

The upper contact portion and the lower contact portion each have an upper weld surface and a lower weld surface that are welded to the inner surface of the tank outer wall. For this reason, the upper and lower contact portions are fused to the inner surfaces of the upper and lower walls of the tank outer wall, and the main body portion holds the space between the upper and lower walls to improve the rigidity of the tank outer wall. Can be made.

The tank outer wall has an outer wall inner surface protruding portion that protrudes toward the inside of the fuel tank, and a flat outer wall inner surface welding surface is formed on the surface facing the upper and lower welding surfaces of the outer wall inner surface protruding portion. For this reason, the upper contact portion and the lower contact portion are securely welded to the upper wall of the tank outer wall and the outer wall inner surface of the lower wall, thereby improving the rigidity of the tank outer wall.

The present invention of claim 2 is a mounting structure for a built-in component of a fuel tank for an automobile, wherein the main body portion of the built-in component is a plurality of plate-like longitudinal reinforcing ribs connecting the upper abutting portion and the lower abutting portion.

In the present invention of claim 2, the main body portion of the built-in component is a plurality of plate-like longitudinal reinforcing ribs connecting the upper contact portion and the lower contact portion. For this reason, the plurality of plate-like vertical reinforcing ribs can improve the rigidity of the body part of the built-in component and are plate-like vertical reinforcing ribs, so that the vertical reinforcing rib, the upper contact portion, and the lower contact portion Can be formed by one-time molding, and molding is easy.

According to a third aspect of the present invention, there is provided a mounting structure for a built-in component of a fuel tank for an automobile, wherein the main body portion of the built-in component is a rod-shaped central shaft that connects the central portion of the upper contact portion and the central portion of the lower contact portion. is there.

According to a third aspect of the present invention, the main body portion of the built-in component is a rod-shaped central axis that connects the central portion of the upper contact portion and the central portion of the lower contact portion. For this reason, the upper contact portion and the lower contact portion can be connected and held by the rod-shaped central axis, and the center shaft, the upper contact portion, and the lower contact portion are aligned with each other because it is a rod-shaped central axis. Therefore, the molding can be easily performed by one-time molding.

According to a fourth aspect of the present invention, there is provided an automobile fuel tank in which a main body portion of a built-in component is provided with a vertical reinforcing rib or a plate-like horizontal reinforcing rib formed at a central axis so as to be orthogonal to the vertical reinforcing rib or the central axis. The built-in component mounting structure.

In the present invention of claim 4, the main body portion of the built-in component is provided with a vertical reinforcing rib or a plate-like horizontal reinforcing rib formed on the central axis so as to be orthogonal to the vertical reinforcing rib or the central axis. For this reason, the rigidity of the vertical reinforcing rib or the central axis can be improved by the plate-shaped lateral reinforcing rib, and the impact to the fuel tank can be absorbed reliably, and the plate-shaped lateral reinforcing rib is used. The horizontal reinforcing rib, the upper abutting portion, and the lower abutting portion can be combined together with the vertical reinforcing rib or the central axis, and can be molded by a single molding process, which is easy to mold.

According to the present invention of claim 5, the main body portion of the built-in component is provided with a plurality of plate-like lateral reinforcing ribs formed so that a longitudinal reinforcing rib is formed on the central axis, and the longitudinal reinforcing rib is formed so as to be orthogonal to the longitudinal reinforcing rib. 1 is a mounting structure of a built-in component of an automobile fuel tank.

In the present invention of claim 5, the main body portion of the built-in component is provided with a plurality of plate-like transverse reinforcing ribs formed so that the longitudinal reinforcing ribs are formed on the central axis and the longitudinal reinforcing ribs are formed to be orthogonal to the longitudinal reinforcing ribs. It was. For this reason, the rigidity of the longitudinal reinforcement rib and the central axis can be improved by the plurality of plate-shaped lateral reinforcement ribs, and the lateral reinforcement rib, the longitudinal reinforcement rib and the central axis are combined to reliably absorb the impact on the fuel tank. Since it is a plate-like vertical reinforcing rib and horizontal reinforcing rib and a rod-shaped central axis, the vertical reinforcing rib, the horizontal reinforcing rib and the central axis are simultaneously combined with the upper abutting portion and the lower abutting portion, Molding can be performed by one-time molding, and molding is easy.

According to a sixth aspect of the present invention, there is provided an automobile fuel tank in which an outer wall inner surface is formed smaller than an upper weld surface and a lower weld surface, and an upper weld surface, a lower weld surface, and an outer wall inner surface are welded. This is a built-in component mounting structure.

According to the sixth aspect of the present invention, the outer wall inner surface is formed smaller than the upper weld surface and the lower weld surface, and the upper weld surface, the lower weld surface, and the outer wall inner surface are welded. For this reason, when the upper weld surface and the lower weld surface are welded to the inner surface of the outer wall, a notch of the molten resin in the weld portion occurs on the upper weld surface and the lower weld surface side, and even if external low temperature impact is applied As a result, stress is not applied to the upper weld surface and the lower weld surface side of the built-in component, and the outer wall of the fuel tank is not damaged.

The present invention of claim 7 is a mounting structure for a built-in component of an automobile fuel tank in which an impact absorbing portion that is broken by an impact is formed on a central shaft or a longitudinal reinforcing rib.

In the present invention of claim 7, an impact absorbing portion that is broken by impact is formed on the central shaft or the longitudinal reinforcing rib. For this reason, when an excessive impact is applied to the fuel tank, the impact absorbing portion of the central shaft or the longitudinal reinforcing rib can be broken to absorb the impact, and the tank outer wall is not damaged.

Since the upper contact portion and the lower contact portion respectively have an upper weld surface and a lower weld surface that are welded to the inner surface of the tank outer wall, the upper contact portion and the lower contact portion are connected to the upper wall and the lower wall of the tank outer wall. By fusing to the inner surface, the main body portion can hold the upper contact portion and the lower contact portion, and the rigidity of the tank outer wall can be improved.

The tank outer wall has an outer wall inner surface protruding part that protrudes to the inside of the fuel tank, and the upper and lower surfaces of the outer wall inner surface protruding part are formed with a flat outer wall inner surface. The contact portion and the lower contact portion are reliably welded to the upper wall of the tank outer wall and the outer wall inner surface of the lower wall, so that the rigidity of the tank outer wall can be improved.

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 component attached to the inside of a fuel tank which is a 1st embodiment of the present invention. It is a front view of the built-in component attached to the inside of the fuel tank, which is the first embodiment of the present invention. FIG. 5 is a cross-sectional view of a built-in component attached to the inside of the fuel tank according to the first embodiment of the present invention, and is a cross-sectional view along the line AA in FIG. 4. FIG. 3 is a partially cutaway perspective view of a built-in component attached to the inside of the outer wall protruding portion of the fuel tank according to the first embodiment of the present invention. It is a partially cutaway front view of the built-in component attached to the inside of the outer wall protrusion of the fuel tank, which is the first embodiment of the present invention. FIG. 5 is a partially cutaway cross-sectional view of a built-in component attached to the inside of the outer wall protruding portion of the fuel tank according to the first embodiment of the present invention, and is a cross-sectional view taken along the line BB in FIG. 4. . It is a perspective view of the built-in component attached to the inside of the fuel tank which is the 2nd Embodiment of this invention. It is a front view of the built-in component attached to the inside of the fuel tank which is the 2nd Embodiment of this invention. It is sectional drawing of the internal component attached to the inside of the fuel tank which is the 2nd Embodiment of this invention, and is sectional drawing along CC line of FIG. FIG. 5 is a partially cutaway perspective view of a built-in component attached to the inside of an outer wall protrusion of a fuel tank, which is a second embodiment of the present invention. It is a partially cutaway front view of the built-in component attached to the inside of the outer wall protrusion of the fuel tank, which is the second embodiment of the present invention. FIG. 14 is a partially cutaway cross-sectional view of a built-in component attached to the inside of the outer wall protruding portion of the fuel tank according to the second embodiment of the present invention, and is a cross-sectional view along the line DD in FIG. 13. . It is a perspective view of the built-in component attached to the inside of the fuel tank which is the 3rd Embodiment of this invention. It is a front view of the built-in component attached to the inside of the fuel tank which is the 3rd Embodiment of this invention. It is sectional drawing of the internal component attached to the inside of the fuel tank which is the 3rd Embodiment of this invention, and is sectional drawing along the EE line of FIG. FIG. 7 is a partially cutaway perspective view of a built-in component attached to the inside of an outer wall protrusion of a fuel tank, which is a third embodiment of the present invention. It is a partially cutaway front view of the built-in component attached to the inside of the outer wall protrusion of the fuel tank, which is the third embodiment of the present invention. FIG. 20 is a partially cutaway cross-sectional view of a built-in component attached to the inside of the outer wall protruding portion of the fuel tank according to the third embodiment of the present invention, and is a cross-sectional view taken along line FF in FIG. 19. . It is sectional drawing of the state which opened the blow molding die and inserted the internal component in the parison which shows the manufacturing method of the fuel tank of this invention. It is sectional drawing of the state which slid the press pin of the blow molding die and clamped the internal component with the slide pin which shows the manufacturing method of the fuel tank of this invention. It is sectional drawing of the state which closed the blow molding die which shows the manufacturing method of the fuel tank of this invention. It is sectional drawing of the state which opened the blow molding die which shows the manufacturing method of the conventional fuel tank. It is sectional drawing of the state which slid the press pin of the blow molding die which shows the manufacturing method of the conventional fuel tank. It is sectional drawing of other conventional built-in components. It is sectional drawing at the time of welding of the built-in component welding surface of other conventional built-in components, and a parison. It is sectional drawing at the time of the welding of the other conventional built-in component built-in component welding surface and a parison. It is a perspective view of other conventional built-in components.

A built-in component mounting structure of an automobile fuel tank 1 according to an embodiment of the present invention will be described with reference to FIGS.
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. Further, a built-in component 20 as shown in FIG. 3 is attached inside 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 the tank outer wall 10 includes, for example, a skin layer 11, an external body layer 12, an external adhesive layer 13, in order from the outside, as shown in FIG. The barrier layer 14, the internal adhesive layer 15, and the internal body layer 16 are formed. A built-in component 20 to be described later is welded to the inner main body layer 16. The built-in component 20 and the inner main body layer 16 are preferably made of a material that is easily welded, for example, the same type of material. The tank outer wall 10 may be a single layer or a multilayer other than six layers.

In the blow molding, when the built-in component 20 is inserted into the cylindrical parison 8, or the cylindrical parison 8 is cut and flattened, the blow mold 40 is opened, and the cavity surfaces on both sides are opened. The built-in component 20 may be attached to the flat parison 8 by attaching.
As the blow molded parison 8, the parison 8 composed of the above six layers is used. A parison 8 having a layer configuration 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). When the outer main body layer 12 contains an inorganic filler, the outer skin layer 11 is used to cover the surface of the outer main body layer 12, and the surface can be smoothed without any inorganic filler appearing on the surface. .

A built-in component 20 is attached inside the fuel tank 1. A method for attaching the built-in component 20 will be described later. The first to third embodiments of the built-in component 20 will be described with reference to FIGS.
First, the built-in component 20 and the state attached to the tank outer wall 10 of the first embodiment will be described with reference to FIGS. The state of being attached to the built-in component 20 and the tank outer wall 10 in the second and third embodiments will be described later.

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. Furthermore, if the same type of material as the tank outer wall 10 of the fuel tank 1 is used, the built-in component 20 and the tank outer wall 10 can be firmly welded.

The built-in component 20 of the first embodiment is provided with an upper abutment portion 21 and a lower abutment portion 22 that are fused to the upper and lower inner surfaces of the tank outer wall 10 to attach the built-in component 20 ”. The upper contact portion 21 is formed with an upper welding surface 21 a that is welded to the upper surface of the tank outer wall 10, and the lower contact portion 22 is formed with a lower welding surface 22 a that is welded to the lower surface of the tank outer wall 10.
The upper welding surface 21 a and the lower welding surface 22 a are formed in a planar manner, and are in close contact with the upper and lower inner surfaces of the tank outer wall 10 to be welded.

The upper contact portion 21 and the lower contact portion 22 are connected by the main body portion 23. In the built-in component 20 according to the first embodiment, the main body 23 includes a rod-shaped central shaft 26 that connects the central portion of the upper contact portion 21 and the central portion of the lower contact portion 22, and the upper contact portion 21. A plurality of plate-like longitudinal reinforcing ribs 24 that connect the lower abutting portions 22 and a plurality of plate-like transverse reinforcing ribs 25 that are formed on the longitudinal reinforcing ribs 24 so as to be orthogonal to the longitudinal reinforcing ribs 24 are provided. .

The central shaft 26 is formed in a rod shape and can hold the upper contact portion 21 and the lower contact portion 22 and is the rod-shaped central shaft 26. Therefore, the upper contact portion is formed by a single molding process. 21 and the lower abutting portion 22 can be molded integrally at the same time, and molding is easy.
The central shaft 26 can be omitted when the vertical reinforcing rib 24 is used.

As shown in FIGS. 3 to 5, the longitudinal reinforcing ribs 24 are formed radially from the central axis 26 in the form of four plates. The vertical reinforcing rib 24 has an upper end and a lower end formed integrally with the upper contact portion 21 and the lower contact portion 22, a side end on the central shaft 26 side formed integrally with the central shaft 26, and a side end on the outer peripheral side. Is formed in a circular arc shape with a recessed central portion.

In the present embodiment, four vertical reinforcing ribs 24 are formed, but the number is appropriately selected with two or more. Further, the vertical reinforcing ribs 24 are formed vertically, but may be formed obliquely. The plurality of plate-like vertical reinforcing ribs 24 can improve the rigidity in the vertical direction of the main body 23 of the built-in component 20.

Further, when the built-in component 20 is molded, since it is the plate-like longitudinal reinforcing rib 24, it is molded together with the upper abutting portion 21, the lower abutting portion 22 and the central shaft 26 by one molding. Can be formed easily.
As described above, when only the vertical reinforcing rib 24 is sufficient in the vertical direction, only the vertical reinforcing rib 24 can be formed without forming the central shaft 26.

Further, a plurality of plate-like horizontal reinforcing ribs 25 formed so as to be orthogonal to the vertical reinforcing ribs 24 are provided on the vertical reinforcing ribs 24. In the present embodiment, four lateral reinforcing ribs 25 are formed, but one or more can be selected as appropriate. The horizontal reinforcing rib 25 is formed in a disc shape, and is formed integrally with the vertical reinforcing rib 24 and the central shaft 26.

By forming the horizontal reinforcing rib 25, the rigidity in the torsional direction of the vertical reinforcing rib 24 and the central shaft 26 can be improved, and the horizontal reinforcing rib 25, the vertical reinforcing rib 24, and the central shaft 26 are combined to form a fuel. The impact on the tank 1 can be reliably absorbed. Further, the upper abutment portion 21, the lower abutment portion 22, the vertical reinforcing rib 24, the lateral reinforcing rib 25, and the central shaft 26 can be simultaneously formed by a single mold forming, so that the forming is easy.

Next, a state where the built-in component 20 according to the first embodiment is attached to the inside of the fuel tank 1 will be described with reference to FIGS.
As shown in FIGS. 6 to 8, the tank outer wall 10 of the fuel tank 1 is formed with an outer wall inner surface protruding portion 18 that protrudes inside the fuel tank 1 so as to face the upper wall and the lower wall. A planar outer wall inner surface welding surface 17 is formed on a surface of the outer wall inner surface protruding portion 18 facing the upper welding surface 21a and the lower welding surface 22a. For this reason, the outer wall inner surface protruding portion 18 is more rigid than the other portion of the tank outer wall 10 of the fuel tank 1 and can absorb an impact from the outside.
The outer wall inner surface welding surface 17 is welded to the upper welding surface 21 a and the lower welding surface 22 a of the built-in component 20.

As shown in FIGS. 7 and 8, the outer wall inner surface 17 is formed to be smaller than the upper surface 21 a and the lower surface 22 a, and the upper surface 21 a and the lower surface 22 a are the outer wall inner surface 17. It is formed so that a space is formed on the outer peripheral side in the lateral direction. For this reason, when the upper welding surface 21a and the lower welding surface 22a are welded to the outer wall inner surface welding surface 17, the molten protruding portion that is pushed out from the welding portion and protrudes in the lateral direction is located on the upper welding surface 21a and the lower welding surface 22a side. Even if a low temperature impact is applied from the outside, the tank outer wall 10 of the fuel tank 1 is not damaged.

When the built-in component 20 is attached to the outer wall inner surface welding surface 17 of the fuel tank 1, the center axis 26 and the longitudinal reinforcing rib 24 hold the upper welding surface 21a and the lower welding surface 22a and receive the fuel tank 1 from the outer wall inner surface protruding portion 18. When the tank outer wall 10 of the fuel tank 1 expands or contracts, the vertical reinforcing rib 24 and the central shaft 26 hold the outer wall inner surface protruding portion 18 so that the upper portion of the tank outer wall 10 can be absorbed. It is possible to prevent the tank outer wall 10 from excessively expanding and contracting by piercing the wall and the lower wall.
Even if the tank outer wall 10 is twisted, the lateral reinforcing rib 25 can prevent the tank outer wall 10 from being twisted.

Next, the state of being attached to the built-in component 20 and the tank outer wall 10 according to the second embodiment will be described with reference to FIGS. As shown in FIGS. 9 to 11, the built-in component 20 according to the second embodiment is different from the built-in component 20 according to the first embodiment in that the lateral reinforcing rib 25 is not provided, and other portions are the same. Therefore, different parts will be described, and description of similar parts will be omitted.

The built-in component 20 of the second embodiment is provided with an upper abutment portion 21 and a lower abutment portion 22 that are attached to the upper and lower inner surfaces of the tank outer wall 10 to attach the built-in component 20 ”.
The upper contact portion 21 and the lower contact portion 22 are connected by the main body portion 23. In the built-in component 20 according to the second embodiment, the main body 23 includes a rod-shaped central shaft 26 that connects the central portion of the upper contact portion 21 and the central portion of the lower contact portion 22, and the upper contact portion 21. A plurality of plate-like longitudinal reinforcing ribs 24 for connecting the lower contact portions 22 are provided. The lateral reinforcing rib 25 is not provided.

The central shaft 26 is formed in a rod shape and can hold the upper contact portion 21 and the lower contact portion 22 and is the rod-shaped central shaft 26. Therefore, the upper contact portion is formed by a single molding process. 21 and the lower abutting portion 22 can be molded simultaneously, and molding is easy.
The central shaft 26 can be omitted when the vertical reinforcing rib 24 is used.

As shown in FIGS. 9 to 11, the vertical reinforcing ribs 24 are formed radially from the central shaft 26 in the form of four plates. The vertical reinforcing rib 24 has an upper end and a lower end formed integrally with the upper contact portion 21 and the lower contact portion 22, a side end on the central shaft 26 side formed integrally with the central shaft 26, and a side end on the outer peripheral side. Is formed in a circular arc shape with a recessed central portion.
The vertical reinforcing ribs 24 can improve the rigidity for holding the upper contact portions 21 and the lower contact portions 22 without the horizontal reinforcing ribs 25. Further, since there is no lateral reinforcing rib 25, the mold structure is not complicated and the moldability can be improved.

Next, a state in which the built-in component 20 according to the second embodiment is attached to the inside of the fuel tank 1 will be described with reference to FIGS.
The tank outer wall 10 of the fuel tank 1 is formed with an outer wall inner surface protruding portion 18 that protrudes to the inside of the fuel tank 1. A planar outer wall inner surface welding surface 17 is formed on a surface of the outer wall inner surface protruding portion 18 facing the upper welding surface 21a and the lower welding surface 22a.

As shown in FIGS. 13 and 14, the outer wall inner surface 17 is formed smaller than the upper surface 21 a and the lower surface 22 a, and the upper surface 21 a and the lower surface 22 a are the outer wall inner surface 17. It is formed so that a space is formed on the outer peripheral side in the lateral direction. For this reason, when the upper welding surface 21a and the lower welding surface 22a are welded to the outer wall inner surface welding surface 17, the molten protruding portion that is pushed out from the welding portion and protrudes in the lateral direction is located on the upper welding surface 21a and the lower welding surface 22a side. Even if a low temperature impact is applied from the outside, the tank outer wall 10 of the fuel tank 1 is not damaged.

When the built-in component 20 is attached to the outer wall inner surface welding surface 17 of the fuel tank 1, the center axis 26 and the longitudinal reinforcing rib 24 hold the upper welding surface 21a and the lower welding surface 22a and receive the fuel tank 1 from the outer wall inner surface protruding portion 18. When the tank outer wall 10 of the fuel tank 1 expands or contracts, the vertical reinforcing rib 24 and the central shaft 26 hold the outer wall inner surface protruding portion 18 so that the upper portion of the tank outer wall 10 can be absorbed. By supporting the wall and the lower wall, the tank outer wall 10 can be prevented from excessively expanding and contracting.

Next, the state of being attached to the built-in component 20 and the tank outer wall 10 according to the third embodiment will be described with reference to FIGS. As shown in FIGS. 15 to 17, the built-in component 20 of the third embodiment is different from the built-in component 20 of the first embodiment except that the vertical reinforcing rib 24 and the horizontal reinforcing rib 25 are not provided. Since other parts are the same, different parts will be described, and description of similar parts will be omitted.

The built-in component 20 of the third embodiment is provided with an upper abutment portion 21 and a lower abutment portion 22 that are attached to the upper and lower inner surfaces of the tank outer wall 10 to attach the built-in component 20 ”.
The upper contact portion 21 and the lower contact portion 22 are connected by the main body portion 23. In the built-in component 20 of the third embodiment, the main body portion 23 is a rod-shaped central shaft 26 that connects the central portion of the upper contact portion 21 and the central portion of the lower contact portion 22. The vertical reinforcing rib 24 and the horizontal reinforcing rib 25 are not provided.

The central shaft 26 is formed in a rod shape and can hold the upper contact portion 21 and the lower contact portion 22 and is the rod-shaped central shaft 26. Therefore, the upper contact portion is formed by a single molding process. 21 and the lower abutting portion 22 can be molded simultaneously, and the vertical reinforcing ribs 24 and the lateral reinforcing ribs 25 are not provided, so that the mold structure is simplified and the molding is easy.

Next, a state where the built-in component 20 according to the third embodiment is attached to the inside of the fuel tank 1 will be described with reference to FIGS.
The tank outer wall 10 of the fuel tank 1 is formed with an outer wall inner surface protruding portion 18 that protrudes to the inside of the fuel tank 1. A planar outer wall inner surface welding surface 17 is formed on a surface of the outer wall inner surface protruding portion 18 facing the upper welding surface 21a and the lower welding surface 22a.

When the built-in component 20 is attached to the outer wall inner surface welding surface 17 of the fuel tank 1, the central shaft 26 holds the upper welding surface 21 a and the lower welding surface 22 a to absorb the impact from the fuel tank 1 received from the outer wall inner surface protrusion 18. When the tank outer wall 10 of the fuel tank 1 expands or contracts, the central shaft 26 holds the outer wall inner surface protruding portion 18 to support the upper wall and the lower wall of the tank outer wall 10, 10 can be prevented from excessively expanding and contracting.

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. 21, 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. 22, 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 built-in component 20 and the pressing pins 42.

Then, since the inner surface of the parison 8 is still in a molten state, the upper welding surface 21a and the lower welding surface 22a of the built-in component 20 can be fused to the parison 8 as described above. At this time, since the built-in component 20 is held by the support bar 41, the built-in component 20 can be reliably attached to a predetermined position of the tank outer wall 10 of the fuel tank 1.
Moreover, the upper welding surface 21a and the lower welding surface 22a can be heated in advance to be in a molten state, thereby improving the welding strength.

After that, as shown in FIG. 23, 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 to slide the 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 10 Outer wall 17 Outer wall inner surface fusion | fusion part 18 Outer wall inner surface protrusion part 20 Built-in component 21 Upper contact part 22 Lower contact part 23 Main-body part 24 Vertical reinforcement rib 25 Horizontal reinforcement rib 26 Center axis

Claims (7)

In the built-in component mounting structure of a fuel tank for automobiles, which has a tank outer wall formed with a synthetic resin and has a built-in component inside,
The built-in component includes an upper abutment portion and a lower abutment portion that are fused to the upper and lower inner surfaces of the tank outer wall of the fuel tank, and a main body that connects the upper abutment portion and the lower abutment portion. Part
The upper contact portion and the lower contact portion each have an upper weld surface and a lower weld surface that are welded to the inner surface of the tank outer wall,
The tank outer wall is formed with an outer wall inner surface protruding portion that protrudes to the inside of the fuel tank, and a flat outer wall inner surface is formed on the surface of the outer wall inner surface protruding from the upper and lower welding surfaces. A mounting structure for a built-in part of a fuel tank for an automobile characterized by the above. 2. The structure for mounting a built-in component of an automobile fuel tank according to claim 1, wherein the main body portion of the built-in component is a plurality of plate-like longitudinal reinforcing ribs connecting the upper abutting portion and the lower abutting portion. The built-in component for a fuel tank for an automobile according to claim 1 or 2, wherein the main body portion of the built-in component is a rod-shaped central shaft that connects the central portion of the upper abutting portion and the central portion of the lower abutting portion. Mounting structure. The main body portion of the built-in component is provided with a plate-like lateral reinforcing rib formed so as to be orthogonal to the longitudinal reinforcing rib or the central axis on the vertical reinforcing rib or the central axis. 4. A mounting structure for a built-in component of an automobile fuel tank according to any one of 3 above. The body part of the built-in component has the longitudinal reinforcing rib formed on the central axis, and the vertical reinforcing rib is provided with a plurality of plate-like lateral reinforcing ribs formed to be orthogonal to the vertical reinforcing rib. The mounting structure of the built-in component of the fuel tank for automobiles according to any one of claims 1 to 4. 6. The outer wall inner surface welded surface is formed smaller than the upper welded surface and the lower welded surface, and the upper welded surface, the lower welded surface, and the outer wall inner surface welded surface are welded. 2. A mounting structure for a built-in component of an automobile fuel tank according to claim 1. The mounting structure for a built-in component of an automobile fuel tank according to any one of claims 1 to 6, wherein an impact absorbing portion that is broken by an impact is formed on the central shaft or the longitudinal reinforcing rib.