JP2018177003A - Support pillar component of fuel tank for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support pillar component of fuel tank for automobile which can surely absorb stress no matter from which direction the stress is applied, and which is breakable at a body part in the case where an excessive impact is applied.SOLUTION: A support pillar component 20 which is mounted inside a tank outer wall 10 of a fuel tank for automobile has an upper contact part 21 and a lower contact part 22, and a body part 25. The body part 25 includes a plurality of vertical ribs 23 and a central space part 24 which is a space for communicating from the upper contact part 21 to the lower contact part 22. The vertical rib 23 is formed in a tabular shape and a cross section of a portion in the vertical direction of the vertical rib 23 is formed to be the smallest. The plurality of vertical ribs 23 are mounted at even angles toward the radial direction of the body part 25 from the central space part 24 around a line connecting the center of the upper contact part 21 and the center of the lower contact part 22.SELECTED DRAWING: Figure 3

Description

The present invention relates to a support member for a fuel tank made of thermoplastic synthetic resin, and more particularly to a support member for a fuel tank having an outer support member formed by blow molding a thermoplastic synthetic resin member. It is a thing.

Conventionally, metal fuel tanks have been used as fuel tank structures for automobiles, but in recent years, thermoplasticity has been achieved due to weight reduction of vehicles, absence of rust, ease of forming into a desired shape, etc. Products made of synthetic resin have come to be used.
In the production of thermoplastic synthetic resin fuel tanks for automobiles, a blow molding method has often been 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 made cylindrical and extruded from above, and the parison is sandwiched between molds and air is blown into the parison to produce a fuel tank for an automobile.

On the other hand, also in the blow molding method, in order to improve the rigidity of the outer wall of the tank or to provide a column component having another function inside the fuel tank is required.
In order to provide a support | pillar component in the inside of a fuel tank, as shown in FIG. 15, it may carry out (for example, refer patent document 1).
First, as shown in FIG. 15, the support post 120 is placed on the support bar 141 before the parison 108 enters the blow mold 140, and the blow mold 140 is opened and positioned therein. Thereafter, with the blow molding die 140 kept open, the parison 108 is lowered so that the column part 120 is positioned inside the parison 108.

Thereafter, before closing the blow molding die 140, the pressing pins 142 are taken out from both sides of the blow molding die 140, and the parison 108 is pressed to press the parison 108 to the supporting member welding surface 123 which is the side end of the column part 120. Press it. At this time, since the inner surface of the parison 108 is not solidified yet, the parison 108 and the support member welding surface 123 of the column component 120 can be welded.
Then, the support rod 141 is lowered to close the blow molding die 140 and blow air, thereby performing blow molding.

In this case, the main body 121 provided between the supporting member welding surface 123 and the supporting member welding surface 123 of the column component 120 prevents the vibration of the fuel tank and the expansion of the fuel tank, and secures the rigidity of the fuel tank. It was
Further, as shown in FIG. 16, as a support part 220 of a fuel tank 1 for an automobile having an outer wall formed of a synthetic resin, the upper part is attached by welding to the upper and lower inner surfaces of the tank outer wall of the fuel tank. It is conceivable to have a contact portion 221 and a lower contact portion 222, and a rigid main portion 223 connecting the upper contact portion 221 and the lower contact portion 222 (see, for example, Patent Document 2).

In this case, a central axis 225 is provided at the center of the main body portion 223, and four plate-like longitudinal reinforcing ribs 224 extending in the longitudinal direction are formed around the central axis 225. The vertical reinforcing rib 224 is integrally attached to the upper contact portion 221 and the lower contact portion 222. The longitudinal reinforcing rib 224 is formed to be narrow in width near the center, and is formed to be broken by stress at a narrow portion.

However, when stress is applied to the column component 220 in the direction in which the longitudinal reinforcing rib 224 is not present (the method shown by the arrows in FIGS. 16 and 17), the narrowed portion of the longitudinal reinforcing rib 224 is not broken. There is a risk that the upper contact portion 221 or the lower contact portion 222 and the welding surface of the tank outer wall may break. In this direction, the stress is transmitted in the central axis 225 without the cross-sectional shape being deformed in the main body 223.

Japanese Patent Application Laid-Open No. 6-143396 JP, 2016-128277, A

  Therefore, the present invention provides a support part of an automotive fuel tank that can be broken at the main body when it receives stress from any direction without fail and absorbs excessive stress. To be an issue.

The present invention according to claim 1 for solving the above-mentioned problems relates to a column component attached to the inside of a tank outer wall of an automotive fuel tank having a tank outer wall formed of a synthetic resin,
The column component has upper and lower abutments attached to the upper and lower inner surfaces of the tank outer wall of the fuel tank to attach the column component, and a main body connecting the upper and lower abutments.
The main body portion includes a plurality of vertical ribs connecting the upper contact portion and the lower contact portion, and the upper contact portion to the lower contact portion centering on a line connecting the centers of the upper contact portion and the lower contact portion It has a central space that is a communicating space,
The longitudinal rib is formed in a plate shape, and the cross-sectional area of a part in the vertical direction of the longitudinal rib is formed to be the smallest, and the plurality of longitudinal ribs are a line connecting the centers of the upper contact portion and the lower contact portion It is a pillar part of a fuel tank for an automobile characterized by being mounted at a uniform angle in a radial direction of the main body from the central space at the center.

According to the first aspect of the present invention, in the column component attached to the inside of the tank outer wall of the automotive fuel tank having the tank outer wall formed of a synthetic resin, the column component is welded to the upper and lower inner surfaces of the tank outer wall An upper contact portion and a lower contact portion for attaching the column component, and a main body portion connecting the upper contact portion and the lower contact portion. Therefore, the upper and lower abutment 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 to prevent excessive expansion and contraction.

The main body portion has a plurality of longitudinal ribs connecting the upper contact portion and the lower contact portion. Therefore, the upper abutment portion and the lower abutment portion can be supported by the plurality of vertical ribs, and the rigidity of the tank outer wall can be improved, and when an impact is applied to the tank outer wall, the plurality of vertical ribs Can be absorbed to prevent damage to the tank outer wall.

The main body portion has a central space portion which is a space communicating from the upper contact portion to the lower contact portion centered on a line connecting the centers of the upper contact portion and the lower contact portion. Therefore, when an impact is applied to the outer wall of the tank, the plurality of longitudinal ribs can be deformed and absorbed in the direction of the central space when they deform in order to absorb the stress of the impact, and the longitudinal ribs Until they interfere with each other, they can be deformed and the amount of absorption of stress can be increased.

The vertical rib is formed in a plate shape, and the cross-sectional area of a part of the vertical rib in the vertical direction is formed to be the smallest. Therefore, when an excessive impact is applied to the tank outer wall, the vertical rib The portion where the cross-sectional area is formed to be the smallest can be reliably broken by the impact to absorb the impact and prevent damage to the outer wall of the tank.

The plurality of longitudinal ribs are attached at equal angles in the radial direction of the main body from the central space, centering on a line connecting the centers of the upper abutment and the lower abutment. Therefore, against impact from any direction, any of the plurality of longitudinal ribs can absorb the stress of the impact and prevent damage to the outer wall of the tank.

According to a second aspect of the present invention, the longitudinal rib is a pillar part of a fuel tank for an automobile, in which the outer side near the center in the vertical direction of the longitudinal rib is recessed to reduce the cross-sectional area.

According to the second aspect of the present invention, since the longitudinal rib is formed so that the outer side near the center in the vertical direction of the longitudinal rib is recessed and the cross-sectional area is small, when the tank outer wall receives an excessive impact, the vertical rib The area around the center of the tank can be reliably broken by the impact to absorb the impact and prevent damage to the outer wall of the tank.

According to the present invention of claim 3, the inner side end of the longitudinal rib toward the center is a pillar part of a fuel tank for an automobile having a curved or polygonal cross-sectional shape in the lateral direction.

In the present invention of claim 3, the inner side end of the longitudinal rib toward the center is formed in a curved or polygonal cross-sectional shape. For this reason, when an impact is applied to the outer wall of the tank and the longitudinal rib bends toward the central space portion, since the inner side ends bent toward the center of the central space portion have corners removed, It is possible to have a deflection margin to contact, and it is possible to absorb the impact of the tank outer wall and prevent damage to the tank outer wall.

According to the fourth aspect of the present invention, the longitudinal rib has a length of 10 to 20 mm in a portion connected to the upper contact portion and the lower contact portion, and a horizontal length of the central portion of 3 to 7 mm. It is a column component of the tank.

In the present invention of claim 4, since the length of the portion connected to the upper contact portion and the lower contact portion is 10 to 20 mm, the vertical rib securely holds the upper contact portion and the lower contact portion. Can support the upper and lower portions of the tank outer wall of the fuel tank. When the length of the portion where the vertical rib connects to the upper contact portion and the lower contact portion is less than 10 mm, the force to connect the vertical rib to the upper contact portion and the lower contact portion is weak and stress is applied In such a case, there is a risk that the longitudinal rib may break from the upper abutment portion and the lower abutment portion, and if the length of the portion connecting the longitudinal rib to the upper abutment portion and the lower abutment portion exceeds 20 mm, This is because the ribs may protrude from the upper contact portion and the lower contact portion.

Since the longitudinal rib has a lateral length of 3 to 7 mm at the central portion, the rigidity of the tank outer wall is improved, and when the tank outer wall is subjected to an excessive impact, the central portion is reliably broken due to the impact. The shock can be absorbed to prevent damage to the outer wall of the tank.
If the longitudinal length of the longitudinal rib central part is less than 3 mm, the rigidity of the longitudinal rib is low and there is a risk that it will break with a small impact, and if it exceeds 7 mm, it may not break even with an excessive impact. Because there is

The present invention according to claim 5 is a support column part of a fuel tank for an automobile, wherein the thickness of the longitudinal rib is 1.5 to 3 mm.

In the present invention of claim 5, since the thickness of the longitudinal rib is 1.5 to 3 mm, the longitudinal rib has sufficient rigidity, and the rigidity of the tank outer wall is increased by the longitudinal rib to absorb the impact. Can prevent excessive expansion and contraction. If the thickness of the longitudinal rib is less than 1.5 mm, the rigidity of the longitudinal rib is insufficient and it may be difficult to prevent excessive expansion and contraction. When the thickness of the longitudinal rib exceeds 5 mm, the stiffness of the longitudinal rib is large, and it may be difficult to break the central portion of the longitudinal rib.

According to a sixth aspect of the present invention, the upper contact portion and the lower contact portion are formed in a disk shape, and the upper contact portion and the lower contact portion are respectively an upper welding surface welded to the inner surface of the tank outer wall It is a support | pillar component of the fuel tank for motor vehicles which has a lower welding surface.

In the present invention of claim 6, the upper contact portion and the lower contact portion are formed in a disk shape, and the upper contact portion and the lower contact portion are respectively the upper welding surface welded to the inner surface of the tank outer wall It has a lower welding surface. Therefore, the upper welding surface of the upper contact portion and the lower welding surface of the lower contact portion are welded to the inner surfaces of the upper wall and the lower wall of the tank outer wall, and the main body portion is held between the upper and lower walls The rigidity of the tank outer wall can be improved.

The invention according to claim 7 is that the support column part is a support column part of a fuel tank for an automobile formed of high density polyethylene (HDPE).

In the present invention of claim 7, since the support column part is formed of high density polyethylene (HDPE), the strength of the fuel tank can be improved, and even if it is attached to the inside of the fuel tank, swelling by fuel oil etc. Rigidity does not decrease. Furthermore, if the same kind of material is used as the tank outer wall of the fuel tank, the column component and the tank outer wall can be welded firmly.

The longitudinal rib of the column component is formed in a plate shape, and the cross-sectional area of a portion of the longitudinal rib in the vertical direction is formed to be the smallest, so when an excessive impact is applied to the tank outer wall, the impact It can be reliably broken to absorb impact and prevent damage to the tank outer wall.
Since the plurality of longitudinal ribs are attached at an equal angle from the central direction to the radial direction, any of the plurality of longitudinal ribs can absorb the stress of the impact against an impact from any direction. .

Since the main body has a central space, when the impact is applied to the outer wall of the tank, the plurality of longitudinal ribs deform in the direction of the central space as they deform to absorb the stress of the impact. It can be absorbed, it can be deformed and the amount of absorption of stress can be increased until the longitudinal ribs interfere with each other.

FIG. 1 is a perspective view of a fuel tank according to an embodiment of the present invention. It is a partial expanded sectional view which shows the structure of the outer wall of the fuel tank of this invention. FIG. 1 is a perspective view of a column component attached to the inside of a fuel tank according to an embodiment of the present invention. It is sectional drawing which shows the stress from the horizontal direction of the support | pillar component attached to the inside of a fuel tank which is embodiment of this invention, and is sectional drawing along the BB line of FIG. FIG. 6 is a cross-sectional view of a column component attached to the inside of a fuel tank, which is an embodiment of the present invention, when it is deformed by stress from the lateral direction, and is a cross-sectional view along line B-B in FIG. It is sectional drawing which shows the stress from diagonally downward direction of the support | pillar component attached to the inside of a fuel tank which is embodiment of this invention, and is sectional drawing along the B-B line of FIG. FIG. 6 is a cross-sectional view of a column component attached to the inside of a fuel tank, which is an embodiment of the present invention, when it is deformed by stress from an oblique downward direction, and is a cross-sectional view along line B-B in FIG. It is sectional drawing which shows the stress from the twist direction of the support | pillar component attached to the inside of a fuel tank which is embodiment of this invention, and is sectional drawing along the BB line of FIG. FIG. 6 is a cross-sectional view of a column component attached to the inside of a fuel tank, which is an embodiment of the present invention, when it is deformed by stress from a twisting direction, and is a cross-sectional view along line B-B in FIG. It is a front view of a state where a pillar part which is an embodiment of the present invention is attached to an inside of a fuel tank. FIG. 11 is a cross-sectional view of a state in which a column component is attached to the inside of a fuel tank, which is an embodiment of the present invention, and is a cross-sectional view along the line C-C in FIG. 10; It is sectional drawing which shows the manufacturing method of the fuel tank of this invention, the state which open | released the blow molding die and inserted the support | pillar component in the parison. It is sectional drawing which shows the manufacturing method of the fuel tank of this invention, slides the press pin of the blow molding die, and clamps support | pillar components by a slide pin. 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 a perspective view of the other conventional pillar component. FIG. 11 is a cross-sectional view of another conventional column part, taken along line C-C of FIG. 10;

A column component 20 of a fuel tank 1 for a motor vehicle according to an embodiment of the present invention will be described based on FIGS.
In the embodiment of the present invention, as shown in FIG. 1, the fuel tank 1 to which the column component 20 is attached has a pump unit mounting hole 4 for inserting a fuel pump (not shown) or the like into and out of the fuel tank 1. It is formed on the top surface. Further, a fuel injection hole 5 for injecting fuel from an inlet pipe (not shown) is formed on the side or upper surface of the fuel tank 1. In the inside of the fuel tank 1, a column component 20 as shown in FIG. 3 is attached.

Further, the outer peripheral rib 2 is formed over the entire periphery of the fuel tank 1, and mounting holes 3 are formed over several places at predetermined locations such as the corner portions of the outer peripheral rib 2, and the mounting holes 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 mounting hole 3 and to attach the fuel tank 1 to the vehicle body by the belt.
Further, on the upper surface of the fuel tank 1, mounting portions 6 are formed at various places to which a hose or the like for collecting the fuel vapor inside is connected.

In the present embodiment, the fuel tank 1 is formed by blow molding, and the tank outer wall 10 is, for example, a skin layer 11, an outer main body layer 12, an outer adhesive layer 13, in order from the outside as shown in FIG. A barrier layer 14, an inner adhesive layer 15 and an inner body layer 16 are formed. The post parts 20 described later are welded to the inner main body layer 16. The post 20 and the inner body layer 16 are preferably made of materials that are easy to weld, such as the same type of material. Moreover, the tank outer wall 10 can be made into a multilayer other than 1 layer or 6 layers.

In the blow molding, when the column part 20 is inserted into the inside of the cylindrical parison 8 or the cylindrical parison 8 is cut open and made into a flat plate, the blow molding mold 40 is opened and the cavity surfaces on both sides are formed. In some cases, the support 20 is attached to the flat parison 8 by mounting.
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 or more layers can also be used. In addition, although the skin layer 11 is used when mixing a regeneration member, a filler and the like into the outer main body layer 12, the skin layer 11 can be omitted. Furthermore, if a material having rigidity and fuel resistance is used, it is also possible to use a single layer parison.

The skin layer 11 and the outer main body layer 12 are preferably made of thermoplastic synthetic resin that has high impact resistance and maintains rigidity against fuel oil, and is preferably made 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 inorganic filler does not come out on the surface, and the surface can be made smooth. .

A support post 20 is attached to the inside of the fuel tank 1. The method of attaching the column component 20 will be described later. An embodiment of the support post 20 will be described with reference to FIGS.
First, the shape of the column component 20 of the embodiment will be described based on FIGS. 3 to 9, and the state of being attached to the tank outer wall 10 will be described based on FIGS. 10 and 11.

The column component 20 can be formed of a fuel-resistant thermoplastic synthetic resin such as polyacetal or high density polyethylene (HDPE). Thus, the strength of the fuel tank 1 can be improved, and even if the fuel tank 1 is mounted inside, the rigidity does not decrease due to swelling or the like by the fuel oil. Furthermore, if the same kind of material as the tank outer wall 10 of the fuel tank 1 is used, that is, the inner surface of the tank outer wall 10 is formed of high density polyethylene (HDPE) and the column component 20 is formed of high density polyethylene (HDPE) For example, the column part 20 and the tank outer wall 10 can be welded firmly.

As shown in FIG. 3, in the column component 20 according to the embodiment of the present invention, a disk-shaped upper contact portion 21 and a lower contact portion 22 for attaching the column component 20 by welding to upper and lower inner surfaces of the tank outer wall 10. Is provided. The column component 20 also has a plurality of longitudinal ribs 23 connecting the upper abutment 21 and the lower abutment 22.

The upper contact portion 21 is formed with an upper welding surface 21a welded to the upper surface of the tank outer wall 10, and the lower contact portion 22 is formed with a lower welding surface 22a welded to the lower surface of the tank outer wall 10. The upper welding surface 21a and the lower welding surface 22a are both disk-shaped and formed flat, and are in close contact with the upper and lower inner surfaces of the tank outer wall 10 and welded.

The plurality of longitudinal ribs 23 connecting the upper contact portion 21 and the lower contact portion 22 are all formed in the same shape. The plurality of vertical ribs 23 support the upper contact portion 21 and the lower contact portion 22. The upper welding surface 21a and the lower welding surface 22a are welded to the tank outer wall 10, and the plurality of vertical ribs 23 support the tank outer wall 10 to improve the rigidity of the tank outer wall 10 against expansion and contraction of the tank outer wall 10. ing. Further, when an impact is applied to the tank outer wall 10, the plurality of longitudinal ribs 23 can absorb the impact and prevent damage to the tank outer wall.

As shown in FIG. 3, the longitudinal rib 23 is formed in a plate shape, and the outer side of the longitudinal rib central portion 23 a which is the central portion in the vertical direction of the longitudinal rib 23 is recessed to form a small cross-sectional area. In the present embodiment, in the longitudinal rib 23, the central portion is narrowed in a substantially triangular shape, and the apex of the triangular shape is the longitudinal rib central portion 23a. Therefore, the longitudinal rib central portion 23a is formed to have the smallest width in the lateral direction.
Therefore, the longitudinal rib upper end portion 23b connected to the upper abutment portion 21 of the longitudinal rib 23 and the vertical rib lower end portion 23c connected to the lower abutment portion 22 of the vertical rib 23 are formed to be the widest.

Therefore, in the longitudinal rib 23, the longitudinal rib central portion 23a is the weakest in rigidity, and when an excessive impact is applied to the tank outer wall 10, the longitudinal rib central portion 23a of the longitudinal rib 23 is surely broken by the impact. The shock can be absorbed to prevent damage to the tank outer wall 10.
The longitudinal rib 23 may not only be narrowed in a central portion in a substantially triangular shape, but also may be narrowed in an arc shape so that the width in the lateral direction is smallest at the central portion of the arc.

As shown in FIG. 4, in the present embodiment, eight longitudinal ribs 23 are used as the plurality of longitudinal ribs 23. The eight longitudinal ribs 23 are attached at an equal angle, ie, 45 degrees respectively, from the central direction to the radial direction centering on a line connecting the centers of the upper contact portion 21 and the lower contact portion 22. ing. For this reason, as described later, any of the eight longitudinal ribs 23 can absorb the stress of the impact against the impact from any direction, and the damage of the tank outer wall 10 can be prevented. Although eight vertical ribs 23 are used in the present embodiment, an appropriate number other than eight can be used. Also in this case, the longitudinal ribs 23 are attached at an equal angle from the central direction toward the radial direction.

As shown in FIG. 4, the plurality of longitudinal ribs 23 have a central space portion 24 centered on a line connecting the centers of the upper contact portion 21 and the lower contact portion 22. The central space portion 24 is formed as a space communicating from the upper contact portion 21 to the lower contact portion 22. That is, there is no longitudinal rib inner end portion 23d which is a side end on the center side of the longitudinal rib 23 in contact with the central space portion 24 from the upper portion to the lower portion.

For this reason, as described later, when an impact is applied to the tank outer wall 10, the plurality of longitudinal ribs 23 deform in the direction of the central space 24 when being deformed in order to absorb the stress of the impact. It can be absorbed, and deformation can occur until the inner side ends of the longitudinal ribs 23 interfere with each other, and the amount of absorption of stress can be increased.

As shown in FIG. 4, the longitudinal rib inner end portion 23d of the longitudinal rib 23 can be formed into a triangular shape in which the cross-sectional shape in the lateral direction has an angle of the end every other sheet. The cross-sectional shape of the longitudinal rib inner end portion 23d can be curved on an arc other than the triangle, or can be a shape with an angle of the end such as a hexagon removed.
The longitudinal rib inner end portions 23d of the longitudinal ribs 23 may be formed so that not all the longitudinal rib inner end portions 23d but all the longitudinal rib inner end portions 23d have a cross-sectional shape with a corner at the end.

In this case, when the longitudinal rib 23 bends toward the central space portion 24 due to an impact applied to the tank outer wall 10, the deflection until the longitudinal rib inner end portions 23 d contact each other toward the center of the longitudinal rib 23 The impact of the tank outer wall 10 can be absorbed to prevent damage to the tank outer wall 10.

The vertical ribs 23 have the same height in the vertical direction as the distance between the upper wall and the lower wall of the tank outer wall 10 of the fuel tank 1. For example, the height in the vertical direction of the longitudinal rib 23 is about 100 to 150 mm. In this case, the space between the upper and lower portions of the tank outer wall 10 of the fuel tank 1 can be supported by the upper and lower sides of the vertical rib 23, securing the space between the upper and lower portions of the tank outer wall 10 It can support while securing the volume of 1.

The length of the longitudinal rib upper end portion 23b and the longitudinal rib lower end portion 23c which are portions connected to the upper contact portion 21 and the lower contact portion 22 is preferably 10 to 20 mm. In this case, the upper end 23b of the vertical rib and the lower end 23c of the vertical rib are in close contact with each other from the center to the outer periphery of the upper contact portion 21 and the lower contact portion 22 and securely held. The upper and lower portions of the outer wall 10 can be supported.

When the length of the portion where the vertical rib 23 is connected to the upper contact portion 21 and the lower contact portion 22 is less than 10 mm, the force for connecting the vertical rib 23 to the upper contact portion 21 and the lower contact portion 22 is When the stress is applied weakly, there is a possibility that the vertical rib 23 may be broken from the connecting portion of the upper contact portion 21 and the lower contact portion 22, and the vertical rib 23 may be broken at the upper contact portion 21 and the lower contact portion 22. If the length of the connecting portion exceeds 20 mm, the vertical rib 23 may become large in the upper contact portion 21 and the lower contact portion 22 and the vertical rib 23 may protrude from the upper contact portion 21 and the lower contact portion 22 If the upper contact portion 21 and the lower contact portion 22 are made larger, the welding area becomes larger, and the welding process becomes complicated.

The longitudinal rib 23 preferably has a length of 3 to 7 mm in the lateral direction of the longitudinal rib central portion 23a, that is, the length from the longitudinal rib inner tip 23d to the longitudinal rib outer circumferential tip 23e. In this case, the rigidity of the tank outer wall 10 is improved, and when an excessive impact is applied to the tank outer wall 10, the longitudinal rib central portion 23a is reliably broken by the impact to absorb the impact and thereby the tank outer wall 10 damage can be prevented. If the longitudinal length of the longitudinal rib central portion 23a is less than 3 mm, the rigidity of the longitudinal rib 23 is low and there is a risk of breakage due to a small impact, and if it exceeds 7 mm, breakage is caused even with excessive impact. It is because there is a fear.

The thickness of the longitudinal rib 23 is preferably 1.5 to 3 mm. In this case, the longitudinal rib 23 has sufficient rigidity, and the rigidity of the tank outer wall 10 can be increased by the longitudinal rib 23 to absorb an impact and prevent excessive expansion and contraction. If the thickness of the longitudinal rib 23 is less than 1.5 mm, the rigidity of the longitudinal rib 23 may be insufficient, and it may be difficult to prevent excessive expansion and contraction, and the rigidity of the tank outer wall 10 is improved. It becomes difficult. When the thickness of the longitudinal rib 23 exceeds 5 mm, the rigidity of the longitudinal rib 23 may be large and it may be difficult to break the longitudinal rib central portion 23a, and the weight of the column component 20 increases. It is against the weight reduction of the vehicle.

Next, based on FIGS. 4-9, the case where stress is added to the support column part 20 is demonstrated.
4 and 5 show the case where stress is applied to the column component 20 in the lateral direction (the direction of the arrow in FIG. 4). When stress is applied from the lateral direction, as shown by the dotted line in FIG. 5, the longitudinal ribs 23 located in the lateral direction deform so that the longitudinal rib inner tips 23d approach each other, centering the vertical rib inner tips 23d The longitudinal rib outer peripheral tip 23e is deformed so as to rotate. This deformation can absorb stress.

6 and 7 show the case where stress is applied to the column component 20 from the diagonally downward direction (the direction of the arrow in FIG. 6). When stress is applied obliquely downward, as shown by the dotted line in FIG. 7, the longitudinal ribs 23 rotate around the inner end 23d of the longitudinal rib such that the longitudinal ribs 23 on the left and right with respect to the direction of stress approach each other. And transform. This deformation can absorb stress.

FIGS. 8 and 9 show the case where stress is applied from the direction (the direction of the arrow in FIG. 8) of applying a twist to the column part 20. FIG. When stress is applied from the twisting direction, as shown by the dotted line in FIG. 8, the longitudinal rib 23 deforms so as to rotate in the direction in which the twist is applied about the longitudinal rib inner end 23d. This deformation can absorb stress.

Next, referring to FIGS. 10 and 11, a state in which the column component 20 according to the embodiment of the present invention is attached to the inside of the fuel tank 1 will be described. 11 is a cross-sectional view taken along the line C-C of FIG.
As shown in FIG. 10, the tank outer wall 10 of the fuel tank 1 is formed with an outer wall inner surface projecting portion 18 projecting to the inside of the fuel tank 1 so as to face the upper wall and the lower wall. A flat outer wall inner surface welding surface 17 is formed on the surface facing the upper welding surface 21 a and the lower welding surface 22 a of the outer wall inner surface projecting portion 18. For this reason, the rigidity of the outer wall inner surface projecting portion 18 is improved more than the other portions of the tank outer wall 10 of the fuel tank 1, and the external impact can be absorbed.
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 column component 20.

As shown in FIGS. 10 and 11, the outer wall inner welding surface 17 is smaller than the upper welding surface 21a and the lower welding surface 22a, and the upper welding surface 21a and the lower welding surface 22a are outer wall inner welding surfaces 17 It is formed so that a space can be made on the outer peripheral side in the lateral direction more than that. 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 melted protruding portion extruded from the welding portion and protruding in the lateral direction is the upper welding surface 21a and the lower welding surface 22a side No external damage to the outer wall 10 of the fuel tank 1 occurs even if an external low temperature impact is applied.

When the column part 20 is attached to the outer wall inner surface welding surface 17 of the fuel tank 1, the vertical rib 23 of the main body 25 holds the upper welding surface 21a and the lower welding surface 22a and receives from the fuel tank 1 Shock can be absorbed. Furthermore, when an excessive impact is applied from the outside, the longitudinal rib central portion 23 a of the longitudinal rib 23 is not broken, and the tank outer wall 10 is not damaged.

Also, even when the tank outer wall 10 of the fuel tank 1 expands or contracts, the vertical rib 23 of the main body 25 holds the outer wall inner surface projecting portion 18 to support the upper wall and the lower wall of the tank outer wall 10. Can prevent excessive expansion and contraction.
Further, even if the tank outer wall 10 is twisted, the longitudinal ribs 23 of the column component 20 can prevent the tank outer wall 10 from being twisted.

Next, a method of manufacturing the fuel tank 1 of the present invention by blow molding will be described based on FIGS. 12 to 14.
First, as shown in FIG. 12, the parison 8 is lowered to the inside of the open blow molding mold 40, and while the parison 8 is preblown, the column component 20 is held on the support rod 41, and the column component 20 is parison 8 Place inside the

Then, as shown in FIG. 13, 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 in the blow molding die 40 are slid, and the parison 8 is pressed so as to be sandwiched between the column component 20 and the pressing pins 42.

Then, since the inner surface of the parison 8 is still in the molten state, the upper welding surface 21 a and the lower welding surface 22 a of the column component 20 can be welded to the parison 8 as described above. At this time, since the column component 20 is held by the support rod 41, the column component 20 can be securely attached to a predetermined position of the tank outer wall 10 of the fuel tank 1.
Moreover, welding strength can be improved by heating the upper welding surface 21a and the lower welding surface 22a in advance to be in a molten state.

Thereafter, as shown in FIG. 14, the support rod 41 is lowered and removed from the blow molding die 40, and the second pinch plate 44 is slid to close the parison 8, and the blow molding die 40 is closed to slide the cutter cutter. Cut the parison 8 at 46. When the blow molding die 40 is closed, the press pin 42 continues to press the parison 8 as it is. Thereby, it is possible to keep holding the support post 20 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 tip end surface of the pressing pin 42 and the inner surface of the cavity 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.

Reference Signs List 1 fuel tank 10 outer wall 20 support part 21 upper abutment 22 lower abutment 23 upper support 24 lower support 25 shock absorber 26 main body

Claims (7)

In a pillar part mounted inside the above-mentioned tank outer wall of an automotive fuel tank having a tank outer wall formed of a synthetic resin,
The column part connects the upper contact part, the lower contact part, the upper contact part and the lower contact part, which are attached to the upper and lower inner surfaces of the tank outer wall of the fuel tank to attach the support part. Has a main body,
The main body portion includes the plurality of longitudinal ribs connecting the upper contact portion and the lower contact portion, and the upper contact portion centered on a line connecting the centers of the upper contact portion and the lower contact portion. A central space which is a space communicating with the lower contact portion from the
The longitudinal rib is formed in a plate shape, and the cross-sectional area of a part of the longitudinal rib in the vertical direction is formed to be the smallest, and the plurality of longitudinal ribs are the upper contact portion and the lower contact portion. A post component for a fuel tank for an automobile, which is mounted at a uniform angle from the central space toward the radial direction of the main body about a line connecting the centers. 2. The support member for a fuel tank for a motor vehicle according to claim 1, wherein the longitudinal rib is formed such that the outer side near the center in the vertical direction of the longitudinal rib is recessed to reduce the cross sectional area. 3. The support member for a fuel tank for a motor vehicle according to claim 1, wherein an inner side end of the longitudinal rib toward the center of the central space portion is formed to have a curved or polygonal cross-sectional shape in the lateral direction. . The length of the portion connecting to the upper contact portion and the lower contact portion is 10 to 20 mm, and the horizontal length of the central portion is 3 to 7 mm. The post part of the automotive fuel tank according to any one of the above. 5. The post part of a fuel tank for an automobile according to claim 1, wherein a thickness of the longitudinal rib is 1.5 to 3 mm. The upper contact portion and the lower contact portion are formed in a disk shape, and the upper contact portion and the lower contact portion are respectively an upper welding surface and a lower welding surface welded to the inner surface of the tank outer wall. The support | pillar component of the fuel tank for motor vehicles as described in any one of the Claims 1 thru | or 5 which have. The automotive fuel tank support column component according to any one of claims 1 to 6, wherein the support column component is formed of high density polyethylene (HDPE).

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