Filler pipe

Abstract

To provide a filler pipe that prevents the generation of variation in wall thickness near a branch portion of a filler pipe body portion and a breather pipe, and is molded by a blow molding method.SOLUTION: In a filler pipe 1, a filler neck body portion 5, a branch portion 6, a filler pipe body portion 2, a breather pipe 3, and a connecting portion 4 are integrally formed by a blow molding method. The filler pipe body portion 2 has a generally straight filler pipe body vertical side part 7 coupled with one end portion of the connecting portion 4 on a cross-section. The breather pipe 3 has a generally straight breather pipe vertical side part 8 coupled to the other end portion of the connecting portion 4 on a cross-section. The branch portion 6, the filler pipe body portion 2 on a fuel tank side of the branch portion 6, the breather pipe 3, and the connecting portion 4 are formed inside an outline of the filler neck body portion 5 when viewed from the filler neck body portion 5 side.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a filler pipe formed by a blow molding method, in which a filler pipe body and a breather pipe are integrally connected at a connection portion. [Background technology]

[0002] Conventionally, a molding method has been proposed for a filler pipe in which a filler pipe main body and a breather pipe are integrally molded by being connected to each other via a connecting portion using a blow molding method (for example, Patent Document 1).

[0003] As shown in FIG. 5, the filler pipe 1 of Patent Document 1 has a hollow filler pipe main body 2, a hollow breather pipe 3 formed along the filler pipe main body 2, and a plate-shaped connecting portion 4 connecting the filler pipe main body 2 and the breather pipe 3, and the filler pipe main body 2 and the breather pipe 3 are mutually connected at their tip portions.

[0004] A hollow filler neck body 5 is connected to the filler pipe body 2 on the fuel filler port side where the filler pipe body 2 and breather pipe 3 communicate, and the filler neck body 5, filler pipe body 2, breather pipe 3 and connection part 4 are integrally molded by blow molding. The filler neck body 5 is tubular with a circular cross section, and the cross sections of the filler pipe body 2 and breather pipe 3 near the filler neck body 5 are also circular.

[0005] The circles of the filler neck body 5 and the filler pipe body 2 are substantially concentric. The inner diameter of the filler pipe body 2 is smaller than the inner diameter of the filler neck body 5, and the inner diameter of the breather pipe 3 is smaller than the inner diameter of the filler pipe body 2.

[0006] Fig. 6(a) is a cross-sectional view taken along line AA in Fig. 5, and Fig. 6(b) is a cross-sectional view taken along line BB in Fig. 5. Fig. 7 is a view showing the positional relationship between Fig. 6(a) and Fig. 6(b) when Fig. 5 is viewed from the filler neck main body 5 side, i.e., from the E direction. As is clear from Fig. 7, the breather pipe 3 protrudes from the filler neck main body 5.

[0007] The blow molding method of Patent Document 1 uses a mold that opens vertically, places a hollow parison on the lower mold, and after closing the mold, blows air into the parison to inflate it and mold it according to the shape of the mold. Also, a slide core is arranged in the mold for the part that forms the filler pipe main body 2, the breather pipe 3, and the connection part 4 in Figure 6(b), and is involved in molding the connection part 4 and its vicinity.

[0008] By the way, in order to blow mold the filler pipe 1 in FIG. 5, the filler neck main body 5, the filler pipe main body 2, the breather pipe 3, and the connection part 4 are arranged as shown in FIG. 7. Therefore, in order to mold the filler neck main body 5 to the branch part 6 of the filler pipe main body 2 and the breather pipe 3, and from the branch part 6 to the filler pipe main body 2, the breather pipe 3, and the connection part 4 in a specified shape and thickness, it is necessary to place the extruded parison on the lower die of the blow molding die while shifting the center of gravity of the extruded parison in the X direction from the central axis in the Z direction, as shown in FIG. 8, and then close the upper die to perform blow molding. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2016-107488 A Summary of the Invention [Problem to be solved by the invention]

[0010] As is clear from FIG. 8 , in the section from the filler neck main body 5 to the branching portion 6 of the filler pipe main body 2 and the breather pipe 3, and from the branching portion 6 to the connection portion 4 between the filler pipe main body 2 and the breather pipe 3, the parison needs to be placed on the mold with its center of gravity shifted, that is, the offset (amount of positional deviation) in the X direction needs to be large, which causes variations in wall thickness in the region near the branching portion 6 of the filler pipe 1 after molding.

[0011] Therefore, the present invention provides a filler pipe that prevents the occurrence of the above-mentioned variations in wall thickness during blow molding. [Means for solving the problem]

[0012] In order to solve the above-mentioned problems, the present invention of claim 1 provides a filler pipe having a filler neck main body, a filler pipe main body and a breather pipe branched off at a branching part on the fuel tank side of the filler neck main body and communicating with the filler neck main body, the filler pipe main body and the breather pipe being connected at a connecting part, and the filler neck main body, the branching part, the filler pipe main body, the breather pipe and the connecting part being integrally formed by a blow molding method, wherein the filler pipe main body has, in cross section, a substantially straight filler pipe main body vertical side part that connects to one end of the connecting part, and the breather pipe has, in cross section, a substantially straight breather pipe vertical side part that connects to the other end of the connecting part, and the branching part, the filler pipe main body on the fuel tank connecting side of the branching part, the breather pipe and the connecting part are formed inside the outer shape of the filler neck main body when viewed from the filler neck main body side.

[0013] In the present invention of claim 1, the filler pipe main body has a substantially straight filler pipe main body vertical side portion in cross section that connects to one end of the connection portion, and the breather pipe has a substantially straight breather pipe vertical side portion in cross section that connects to the other end of the connection portion, and the branch portion, the filler pipe main body portion on the fuel tank connection side of the branch portion, the breather pipe and the connection portion are formed inside the outer shape of the filler neck main body portion when viewed from the filler neck main body side. In other words, since the filler pipe main body portion and the breather pipe are connected to the connection portion in a crushed shape, it is possible to form the filler pipe main body portion and the breather pipe close to each other while maintaining the cross-sectional areas of the conventional filler pipe main body portion and breather pipe.

[0014] Therefore, the branch portion, the filler pipe main body on the fuel tank side of the branch portion, the breather pipe, and the connection portion can be formed inside the outer shape of the filler neck main body when viewed from the filler neck main body side, and the parison can be molded without shifting the center of gravity at the branch portion and the portion from the branch portion to the filler pipe main body, breather pipe, and connection portion, i.e., with zero or an extremely small offset in the X direction of the parison's center of gravity. As a result, it is possible to prevent variations in wall thickness in the vicinity of the branch portion of the molded filler pipe.

[0015] In addition, a substantially straight line includes not only a straight line but also a slight arc shape, and includes cases where the vertical side of the filler pipe main body and the vertical side of the breather pipe are both straight lines, one is straight and the other is slightly arc-shaped, and both the vertical side of the filler pipe main body and the vertical side of the breather pipe are slightly arc-shaped.

[0016] The present invention of claim 2 is the filler pipe of claim 1, wherein the vertical side of the filler pipe main body and the vertical side of the breather pipe are connected to the connection portion substantially perpendicularly.

[0017] When blow molding a filler pipe having a substantially straight filler pipe main body vertical side portion and a breather pipe vertical side portion connected to both ends of the connection portion, the filler pipe main body vertical side portion, the breather pipe vertical side portion and the connection portion can be molded with a uniform wall thickness by using a slide core.

[0018] In the present invention of claim 2, the filler pipe body vertical side portion and the breather pipe vertical side portion are connected to the connection portion substantially perpendicularly, so that the filler pipe body vertical side portion and the breather pipe vertical side portion can be formed shorter than when they are formed at an angle. Also, since the slide core is moved forward and backward in a direction perpendicular to the mold for molding, the movement amount (slide amount) of the slide core can be reduced. As a result, the corners of the crushed portion formed in association with the formation of the filler pipe body vertical side portion and the breather pipe vertical side portion, and the filler pipe body vertical side portion and the breather pipe vertical side portion can be molded with uniform wall thickness. The term "substantially perpendicular" is intended to take into account the draft angle when the mold is opened after molding.

[0019] The present invention of claim 3 is the invention of claim 1 or claim 2, wherein the connection portion is provided at both ends near the center of the vertical side of the filler pipe body, And, This is a filler pipe that is connected near the center of the vertical side of the breather pipe.

[0020] In the present invention as claimed in claim 3, the connection portion is provided at both ends near the center of the vertical side of the filler pipe body, And, Since the filler pipe is connected near the center of the vertical side of the breather pipe, the amount of insertion of the slide core can be almost evenly distributed to both the mold that opens and closes vertically and horizontally.

[0021] As a result, the thickness of the corners of the crushed portions formed in association with the formation of the vertical side portion of the filler pipe main body and the vertical side portion of the breather pipe can be made more uniform.

[0022] The present invention of claim 4 is the invention of claims 1 to 3, in which the filler neck main body is tubular with a circular cross section, and the side opposite the connection between the filler pipe main body and the breather pipe is a filler pipe formed in an arc shape in cross section.

[0023] In the present invention of claim 4, the filler neck main body is tubular with a circular cross section, and the side opposite the connection part between the filler pipe main body and the breather pipe is formed in an arc shape in cross section. Therefore, when the filler pipe main body and the breather pipe are formed within the outer shape of the filler neck main body with the connection part sandwiched therebetween, the cross-sectional areas of the filler pipe main body and the breather pipe can be made large.

[0024] As a result, at the branching portion and at the portion extending from the branching portion to the connection portion between the filler pipe main body and the breather pipe, the cross-sectional areas of the filler pipe main body and the breather pipe are sufficiently secured, while the parison is not shifted in center of gravity, i.e., the offset (amount of positional deviation) of the parison center of gravity in the X direction is zero or extremely small, and the occurrence of variations in wall thickness near the branching portion of the filler pipe after molding can be prevented. Effect of the Invention

[0025] a filler neck body, a filler pipe body and a breather pipe branched at a branching portion on the fuel tank connection side of the filler neck body and communicating with the filler neck body, the filler pipe body and the breather pipe being connected at a connecting portion, and the filler neck body, the branching portion, the filler pipe body, the breather pipe and the connecting portion being integrally formed by a blow molding method, the filler pipe body having a substantially straight filler pipe body vertical side portion in cross section that is connected to one end of the connecting portion, and the breather pipe has a substantially straight breather pipe vertical side portion in cross section that connects to the other end of the connection portion, and the branch portion, the filler pipe main body portion on the fuel tank connection side of the branch portion, the breather pipe, and the connection portion are formed inside the outer shape of the filler neck main body portion when viewed from the filler neck main body portion side. In other words, since the filler pipe main body portion and the breather pipe are connected to the connection portion in a crushed shape, it is possible to form the filler pipe main body portion and the breather pipe close to each other while maintaining the cross-sectional areas of the conventional filler pipe main body portion and breather pipe.

[0026] Therefore, the branching portion, the filler pipe body on the fuel tank side of the branching portion, the breather pipe, and the connection portion can be formed inside the outer shape of the filler neck body when viewed from the filler neck body side, so that the parison can be molded without shifting its center of gravity at the branching portion and the portion from the branching portion to the filler pipe body, breather pipe, and connection portion, i.e., with zero or extremely small offset (positional deviation) of the parison in the X direction. As a result, it is possible to prevent variation in wall thickness in the vicinity of the branching portion of the molded filler pipe. [Brief description of the drawings]

[0027] [Figure 1] FIG. 2 is a front view of a filler pipe formed according to an embodiment of the present invention. [Diagram 2] 2A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line BB in FIG. [Diagram 3]1 is a cross-sectional view showing the relationship between FIG. 2(a) and FIG. 2(b) when viewed from the direction E, and also showing the position of the center of gravity of the parison in the mold for molding the filler pipe main body, the breather pipe, and the connection part. [Figure 4] 11 is a graph showing the effect of an embodiment of the present invention on offset of the position of the center of gravity of the parison. [Diagram 5] FIG. 1 is a front view of a conventional filler pipe (Patent Document 1). [Figure 6] 6A is a cross-sectional view taken along line AA in FIG. 5, and FIG. 6B is a cross-sectional view taken along line BB in FIG. [Figure 7] 5 from a direction E, showing the relationship between FIG. 6(a) and FIG. 6(b). [Figure 8] 6 is a graph showing the offset of the position of the center of gravity of the parison when molding the filler pipe of FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] An embodiment of the present invention will be described with reference to Fig. 1 to Fig. 4. The filler pipe 1 of the present invention is a resin pipe for supplying fuel from a fuel filler port of an automobile body to a fuel tank, and as shown in Fig. 1, a filler neck main body 5 is connected to the filler neck main body 5, and a filler pipe main body 2 and a breather pipe 3 are branched at a branching portion 6 on the fuel tank side of the filler neck main body 5. The filler pipe main body 2 and the breather pipe 3 are connected to each other by a plate-shaped connecting portion 4, and have a three-dimensionally curved shape especially on the fuel tank side. The filler pipe main body 2 and the breather pipe 3 are also connected to each other at their tip portions.

[0029] The filler pipe 1 is integrally formed by blow molding. The fuel filler port end 9 and the fuel tank end 10 are removed after molding, leaving both ends of the filler pipe 1 with openings having circular cross sections.

[0030] Although not shown, for example, a mounting bracket having an injection passage and a groove for mounting a fuel cap so that it can be opened and closed is attached to the opening of filler neck main body 5 on the fuel filler port side, and when refueling, the fuel cap is removed and the nozzle of a fuel supply gun is inserted into the injection passage to fill the fuel.

[0031] Generally, blow molding is a technology in which resin that has been softened by heat (thermoplastic resin) is extruded into a pipe shape (parison), compressed air is blown into the parison while the resin is still soft, the resin is pressed against a mold, and then it is cooled and solidified to form the shape.

[0032] In this embodiment, a horizontal molding die (top-bottom opening and closing type) is used to mold a three-dimensional shape, and a hollow parison is stored in the die by moving a die head that extrudes the parison. The die head may be fixed and the molding die may be moved, or both the die head and the molding die may be moved. For a molding method of the filler pipe main body 2, the breather pipe 3, and the connection part 4, see, for example, Patent Document 1.

[0033] The filler pipe 1 is constructed by laminating multiple resin materials, with the inner layer being formed from high-density polyethylene (HDPE), which has excellent resistance to fuel permeation, and the outer layer being formed from polyethylene that has been made conductive by adding materials such as carbon.

[0034] Fig. 2(a) is a cross-sectional view taken along line AA in Fig. 1. The filler neck main body 5 is cylindrical with a circular cross-section. Fig. 2(b) is a cross-sectional view taken along line BB in Fig. 1, and is a cross-sectional view of the filler pipe main body 2 on the fuel tank side of the branching portion 6, the breather pipe 3, and the connection portion 4. In Fig. 2(b), the cross-sectional areas of the filler pipe main body 2 and the breather pipe 3 are the same as those of the conventional one (Fig. 6). Note that Figs. 2(a) and 2(b) omit the portions behind the cross-section.

[0035] As shown in Fig. 2(b), the filler pipe body 2 and the breather pipe 3 are in contact with an ellipse D and are slightly crushed in the vertical direction. Main unit The vertical side portion 7 of the breather pipe 3 is formed with a breather pipe vertical side portion 8 that connects to the other end of the connection portion 4, and both the filler pipe main body portion 2 and the breather pipe 3 are crushed in the horizontal direction as well.

[0036] The connection part 4 has both ends connected to a filler pipe. Main unit The vertical side 7 and the breather pipe vertical side 8 are connected vertically near the center. In particular, the vertical side 7 and the breather pipe vertical side 8 are slightly crushed in the vertical and horizontal directions, and the filler pipe is attached to both ends of the connection part 4. Main unit By making the vertical side portion 7 and the breather pipe vertical side portion 8 connect vertically, the width of the slide core used in the blow molding die can be narrowed and the amount of penetration can be reduced. Main unit It is possible to make the wall thickness uniform at the vertical side portion 7 and the connection portion between the ellipse D and the breather pipe vertical side portion 8, and it is also possible to form the width of the connection portion 4 narrower.

[0037] In addition, the filler neck main body 5 is tubular with a circular cross section, and the side opposite the connection 4 between the filler pipe main body 2 and the breather pipe 3 is formed in the arc shape of an ellipse D. Therefore, in the crushed shape, the cross-sectional area of ​​the hollow parts of the filler pipe main body 2 and the breather pipe 3 can be made large, and the same cross-sectional area as in the conventional case can be secured.

[0038] 3 is a diagram showing the positional relationship between FIG. 2(a) and FIG. 2(b) when FIG. 1 is viewed from the filler neck main body 5 side, i.e., from the direction E. As is clear from FIG. 3, by forming the above-mentioned filler pipe main body 2 and breather pipe 3 into a flattened shape, the filler pipe main body 2, breather pipe 3 and connection part 4 are formed inside the outer shape of the filler neck main body 5.

[0039] 3 also shows the position of the center of gravity (O') of the parison in the mold for molding the filler pipe body 2, the breather pipe 3, and the connection part 4. In FIG. 3, the position O' of the center of gravity of the parison 15 coincides with the Y axis passing through the center point O of the filler neck body 5 in the X direction.

[0040] 4 is a diagram in which the horizontal axis is the Z direction (from the filler neck main body 5 to the fuel tank) in FIG. 1, and the vertical axis is the position of the center of gravity (X direction) of the parison 15. As is clear from FIG. 4, in this embodiment, the position of the center of gravity of the parison 15 does not change.

[0041] As a result, in the X direction, in the region from the filler neck main body 5 to the branching portion 6, and from the branching portion 6 to the filler pipe main body 2, the breather pipe 3, and the connection portion 4 (within the frame in Figure 1), the parison 15 can be placed and blow molded without changing the position of its center of gravity, thereby preventing variations in thickness near the branching portion 6 of the filler pipe 1 after molding.

[0042] In FIG. 3, the position of the parison 15 in the mold when molding the filler neck body 5 is the same as the position of the parison 15 in the mold for the molding parts of the filler pipe body 2, the breather pipe 3, and the connection part 4 in the X direction, but in the Y direction, it is at the position of the outline of the filler neck body 5, which is slightly lower.

[0043] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the object of the present invention.

[0044] For example, in this embodiment, the filler pipe body 2 and the breather pipe 3 are formed to be tangent to the ellipse D, but as long as the cross-sectional areas of the filler pipe body 2 and the breather pipe 3 are the same as those of the conventional one (FIG. 6) and the position of the center of gravity of the parison 15 in the X direction is the same as when the filler neck body 5 is molded, they do not have to be elliptical. [Explanation of symbols]

[0045] 1 Filler pipe 2 Filler pipe body 3 Breather pipe 4 Connection 5 Filler neck body 6 Branch 7 Filler pipe Main unit Vertical Side 8 Breather pipe vertical side 15 Parison

Claims

1. a filler neck body, a filler pipe body and a breather pipe branched at a branching portion on a fuel tank side of the filler neck body and communicating with the filler neck body, the filler pipe body and the breather pipe being connected at a connecting portion, and the filler neck body, the branching portion, the filler pipe body, the breather pipe and the connecting portion being integrally formed by a blow molding method, the filler pipe body has a substantially linear filler pipe body vertical side portion connected to one end of the connection portion in a cross section, The breather pipe has a substantially linear breather pipe vertical side portion connected to the other end of the connection portion in a cross section, The branch portion, the filler pipe body portion on the fuel tank connection side of the branch portion, the breather pipe, and the connection portion are A filler pipe characterized in that, when viewed from the filler neck main body side, the filler pipe is formed inside the outer shape of the filler neck main body.

2. The filler pipe according to claim 1 , wherein the vertical side portion of the filler pipe main body and the vertical side portion of the breather pipe are connected to the connection portion substantially perpendicularly.

3. 3. The filler pipe according to claim 1, wherein the connection portion is connected at both ends near a center of a vertical side of the filler pipe main body and near a center of a vertical side of the breather pipe.

4. 4. A filler pipe according to claim 1, wherein the filler neck main body is tubular with a circular cross section, and the side opposite the connection portion between the filler pipe main body and the breather pipe is formed in an arc shape in cross section.

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