JP5609528B2 - Fuel tank structure - Google Patents

Description

  The present invention relates to a fuel tank structure.

  In a fuel tank structure provided in a vehicle such as an automobile, it is desired to suppress a change in fuel temperature in the fuel tank. Patent Document 1 describes a heat insulating cover structure in an automobile fuel tank in which a synthetic resin heat insulating cover is supported by a band on the lower surface side of the fuel tank.

  However, in the structure of Patent Document 1, since a heat insulating cover made of synthetic resin is used, there is a risk of increasing cost and increasing weight.

Japanese Utility Model Publication No. 6-47023

  In view of the above facts, an object of the present invention is to obtain a fuel tank structure that can effectively insulate a fuel tank, and can suppress an increase in cost and weight.

According to the first aspect of the present invention, a fuel tank capable of containing fuel therein, a lower surface cover member that forms a lower gap between the lower surface of the fuel tank and covers the lower surface from below, and the lower surface cover A side cover member extending from the member and forming a side gap between the side peripheral surface of the fuel tank and surrounding the side peripheral surface; and having elasticity, the bottom surface as it goes inward from the side cover member A seal member extending obliquely from the side cover member so as to approach the cover member, sealing the side gap between the fuel tank and the side cover member and using at least a part of the gap as a heat insulating air layer And having.

In this fuel tank structure, the lower surface cover member covers the lower surface of the fuel tank from below, and the side cover member surrounds the side peripheral surface (the entire side surface) of the fuel tank. A lower gap is formed between the lower surface of the fuel tank and the cover member, and a side gap is formed between the side surface of the fuel tank and the side cover member. The side gap between the side surface of the fuel tank and the side cover member is sealed by a seal member, and at least a part of this gap is a heat insulating air layer. That is, the heat insulation layer as a sealed air layer is provided on the lower surface and the side surface of the fuel tank. Since it is not necessary to use a heat insulating cover made of synthetic resin for heat insulation, it can be configured at low cost and an increase in weight can be suppressed.
The seal member has elasticity. Therefore, even when the fuel tank is deformed due to, for example, a change in the tank internal pressure, the deformation is absorbed by the elasticity of the seal member, and the state where the side gap is sealed can be stably maintained, so that the heat insulation is improved. .
The seal member extends obliquely from the side cover member so as to approach the lower surface cover member as it goes inward from the side cover member.
With the lower surface cover member, the side surface cover member, and the seal member integrated, the fuel tank is fitted inside the side surface cover member in a direction approaching the lower surface cover member (from above), and the lower surface cover member and the side surface cover are inserted into the fuel tank. When the member and the seal member are mounted, the tip end of the seal member is inclined in the fitting direction, so that the fitting operation is facilitated.

  According to a second aspect of the present invention, in the first aspect of the present invention, the contact portion of the seal member with the fuel tank is above the full tank level of the fuel tank.

  Therefore, even when the fuel in the fuel tank is full, a side gap (insulated air layer) is reliably formed on all sides of the portion where the fuel exists. In the fuel tank, the gas layer above the fuel acts as a heat insulating layer. That is, even if the fuel in the fuel tank is full, the entire surface around the fuel can be insulated. Since the gas layer in the fuel tank is used for heat insulation above the fuel, it can be constructed at a lower cost and the increase in weight is suppressed compared to a structure using a synthetic resin heat insulation cover for heat insulation of this part. it can.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the seal member is formed in a polygonal shape corresponding to a side surface shape of the fuel tank, and the polygonal corner is inside. A slit for locally narrowing the sealing member is formed.

  Since the sealing member is formed in a polygonal shape corresponding to the side surface shape of the fuel tank, the side gap between the fuel tank and the side surface sealing member can be more reliably sealed. Since the slit which narrows this seal member locally locally is formed in the inside of the polygonal corner | angular part, the sealing member becomes easy to bend | curve at a corner | angular part.

In the invention described in claim 4, wherein in the invention described in any one of claim 1 to claim 3, wherein the side cover member is integrally molded with the lower surface cover member.

  Therefore, as compared with the configuration in which the side surface cover member is separated from the lower surface cover member, the number of parts is reduced, and it can be configured at a lower cost and the increase in weight can be suppressed.

  Since the present invention has the above-described configuration, the fuel tank can be effectively insulated, and cost and weight increase can be suppressed.

It is sectional drawing which shows the fuel tank structure of 1st Embodiment of this invention. It is a perspective view which shows the fuel tank structure of 1st Embodiment of this invention. It is a perspective view which shows the sealing member which comprises the fuel tank structure of 1st Embodiment of this invention. It is sectional drawing which expands and shows the fuel tank structure of 1st Embodiment of this invention in the vicinity of the sealing member. It is a top view which expands and shows the sealing member which comprises the fuel tank structure of 1st Embodiment of this invention in the vicinity of a corner | angular part. It is sectional drawing which expands and shows the fuel tank structure of 2nd Embodiment of this invention in the vicinity of the sealing member. It is sectional drawing which expands and shows the fuel tank structure of 3rd Embodiment of this invention in the vicinity of the sealing member. It is sectional drawing which expands and shows the fuel tank structure of the comparative example of this invention in the vicinity of the sealing member. It is sectional drawing which shows the fuel tank structure of 4th Embodiment of this invention.

  FIG. 1 shows a fuel tank structure 12 according to a first embodiment of the present invention. The fuel tank structure 12 includes a fuel tank 14 that can accommodate the fuel GS therein. Although the shape of the fuel tank 14 is not particularly limited, in the present embodiment, the fuel tank 14 is formed in a substantially rectangular parallelepiped box shape by the lower surface 14B, the upper surface 14T, and the four side surfaces 14S. The four side surfaces 14S as a whole constitute a “side circumferential surface” according to the present invention.

  An inlet pipe (not shown) is connected to the fuel tank 14, and fuel can be supplied through the inlet pipe. The fuel tank 14 is provided with a fuel pump and a delivery pipe for delivering fuel to the engine. In the fuel tank 14, a full tank liquid level FL is set. Even in the full tank state, the liquid level does not reach the upper surface of the fuel tank 14, and an air layer 38 is formed between the full tank liquid level FL and the upper surface 14T.

  A plurality of (two in FIG. 1 and FIG. 2) tank band recesses 16 are formed in the lower surface 14B of the fuel tank 14 by being partially recessed upward. A tank band recess 24 of a cover member 18 to be described later is fitted into the tank band recess 16.

  A cover member 18 is disposed on a part of the side surface 14 </ b> S from the lower surface 14 </ b> B of the fuel tank 14. The cover member 18 includes a single lower surface cover member 20 that covers the lower surface 14 </ b> B of the fuel tank 14. The lower surface cover member 20 is formed with a tank band recess 24 corresponding to the tank band recess 16 of the lower surface 14B of the fuel tank 14. The tank band recess 16 is fitted into the tank band recess 16 from below, and the intermediate portion of the tank band 26 is fitted into the tank band recess 24. And the fuel tank 14 is attached to a vehicle body by fixing the both ends of the tank band 26 to a vehicle body.

  In a state in which the tank band recess 24 is fitted in the tank band recess 16, a predetermined lower gap 42 is formed between the lower surface cover member 20 and the lower surface 14 </ b> B of the fuel tank 14. A part of the heat insulating air layer 40 is configured. In the present embodiment, the lower surface cover member 20 is formed in a substantially rectangular shape according to the lower surface of the fuel tank 14.

  From the periphery of the lower surface cover member 20, four side surface cover members 22 are erected upward. The four side cover members 22 surround the side peripheral surface (the entire side surface 14S) from the outside.

  A predetermined lateral gap 44 is formed between each of the side cover members 22 and the side surface 14S of the fuel tank 14. This side gap 44 also constitutes a part of the heat insulating air layer 40. In the present embodiment, each of the side cover members 22 is also formed in a substantially rectangular shape.

  The side cover member 22 has an upper end located above the full liquid level FL. And the upper end part of the side cover member 22 is extended in the diagonal direction so that it may spread outside as it goes upwards. This extended portion is an attachment piece 22T to which a seal member 28 described later is attached.

  In this way, the lower surface cover member 20 and the side surface cover member 22 are integrally formed, and the cover member 18 is formed in a box shape having an open upper surface as a whole. In order to configure the fuel tank structure 12 of the present invention, it is possible to adopt a method in which the fuel tank 14 is brought close to the cover member 18 from above and fitted into the cover member 18.

  A seal member 28 made of an elastic material (for example, rubber) is attached to the attachment piece 22T of the side cover member 22 by an attachment member 30. As shown in FIGS. 2 and 3, the seal member 28 is formed in a shape (in this embodiment, a rectangular frame shape) that can surround the side surface 14 </ b> S of the fuel tank 14 from the outside. As can be seen from FIG. 4, in particular, the seal member 28 of the present embodiment has a certain thickness from the outer peripheral end 28G to the inner peripheral end 28N.

  As shown in detail in FIG. 3, a mounting piece 28 </ b> T bulging toward the outer peripheral side is formed at a predetermined position on the outer peripheral end 28 </ b> G side of the seal member 28. An attachment hole 32 that penetrates the seal member 28 in the thickness direction is formed in the attachment piece 28T. Also, the mounting piece 22T has a mounting hole 34 formed at a position corresponding to the seal member 28. In this embodiment, the attachment member 30 (for example, a rivet, a clip, or a bolt and a nut) is inserted into the attachment holes 32 and 34, and the seal member 28 is attached to the attachment piece 22T.

  As can be seen from FIG. 4, the seal member 28 is attached to the attachment piece 22 </ b> T, the inner peripheral end 28 </ b> N side is lowered, and the seal member 28 is inclined so as to approach the lower surface cover member 20 toward the fuel tank 14. Yes. The inner peripheral end 28N side of the seal member 28 is bent downward (contacted) with the side surface 14S of the fuel tank 14 fitted in the cover member 18 (a part that is not in contact with a part that is in contact). Is indicated by a contact line TL). This contact position is below the attachment hole 32 (the attachment position of the cover member 18 to the attachment piece 22T).

  Further, on the inner peripheral end 28N side of the seal member 28, the contact position with the side surface 14S of the fuel tank 14 is positioned above the full tank liquid level FL of the fuel tank 14 in this way.

  As shown in FIG. 5, a slit 36 that penetrates the seal member 28 in the thickness direction and is opened toward the inside is formed in the corner portion 28 </ b> C of the seal member 28. By forming such a slit 36, the sealing member 28 is partially narrowed at the corner portion 28C, and the flexibility is enhanced. However, the slit 36 is set so as not to reach the outer peripheral end 28G side with respect to the contact line TL so that no gap is generated over the entire circumference in a state where the seal member 28 is in contact with the side surface 14S of the fuel tank 14. It has become.

  Next, a method for configuring the fuel tank structure 12 of the present embodiment and the operation of the fuel tank structure 12 will be described.

  The fuel tank 14 is assembled at a predetermined position in the cover member 18 by fitting the fuel tank 14 into the cover member 18 to which the seal member 28 is attached by the attachment member 30 from the open portion on the upper surface side. Since the seal member 28 is inclined so that the inner peripheral end 28N side thereof is lowered, the seal member 28 is not easily caught by the fuel tank 14 being fitted. That is, since the load for fitting is reduced, workability is improved. In particular, since the inner peripheral end 28N side of the seal member 28 is bent downward, the assembling workability is further improved. Further, in the structure in which the inner peripheral end 28N side of the seal member 28 is inclined upward, there is a concern that a large load acts on the mounting member 30 during fitting, but in this embodiment, the inner peripheral end 28N side of the seal member 28 is lowered. Therefore, the load acting on the mounting member 30 is also reduced.

  In addition, since the sealing member 28 according to the present embodiment is highly flexible because the slits 36 are formed in the corners 28 </ b> C, the load when the fuel tank 14 is fitted into the cover member 18 is further reduced. This improves the workability of assembly.

  When the fuel tank 14 is fitted into the cover member 18 to the position where the tank band recess 24 is fitted in the tank band recess 16, the lower gap 42 is formed between the lower surface 14B of the fuel tank 14 and the lower surface cover member I. Composed. Further, a side gap 44 is formed between each of the side surfaces 14 </ b> S of the fuel tank 14 and the side surface cover member 22. The upper side of the side gap 44 is sealed with a seal member 28. That is, a heat insulating air layer 40 in which the air flow to the outside is blocked is formed between the fuel tank 14 and the cover member 18. Since this heat insulation air layer 40 acts as a heat insulation layer, the temperature rise of the fuel in the fuel tank 14 can be suppressed, and the increase in the internal pressure of the fuel tank 14 can also be suppressed.

  In particular, a slit 36 is formed on the inner side of the contact line TL of the seal member 28 to the fuel tank 14, so that no gap is generated by the slit 36 between the seal member 28 and the side surface 14S of the fuel tank 14. It has become. For this reason, it is possible to more reliably prevent air from entering and leaving the heat insulating air layer 40 and the outside, and to obtain high heat insulating properties.

  Thus, in this embodiment, since the heat insulation air layer 40 which acts as a heat insulation layer around the fuel tank 14 is configured, and a member such as urethane for heat insulation is not necessary, cost and weight increase are suppressed. it can. When a foamed member such as urethane is used, a process for foaming may be required, but in the present embodiment, such a process is not necessary.

  As can be seen from FIG. 1, the air layer 38 in the fuel tank 14 acts as a heat insulating layer above the fuel GS. That is, the lower surface and side surfaces of the fuel GS in the fuel tank 14 can be insulated by the heat insulating air layer 40, and the upper surface can be insulated by the air layer 38. Also on the upper surface of the fuel GS, since a heat insulating material such as urethane is not necessary, an increase in cost and weight can be suppressed.

  In addition, in this embodiment, as shown in FIG. 4, the contact portion of the seal member 28 with respect to the side surface 14 </ b> S of the fuel tank 14 is above the full liquid level FL of the fuel tank 14. Therefore, even if the fuel GS in the fuel tank 14 is full, an air layer is present on the entire surface around the fuel in the fuel tank 14, and effective insulation can be achieved.

  When the internal pressure of the fuel tank 14 varies with the fuel tank 14 assembled at a predetermined position in the cover member 18, the fuel tank 14 is deformed and the position of the side surface 14S is changed as shown by a two-dot chain line in FIG. May change. Further, the fuel tank 14 may be slightly deformed due to variations in manufacturing of the fuel tank 14. In this embodiment, since the seal member 28 has elasticity, the seal member follows such deformation of the fuel tank 14. Thereby, the state which sealed the heat insulation air layer 40 can be maintained stably, and heat insulation can be maintained.

Note that the shape of the seal member, in particular, the structure for attaching the seal member to the cover member is not limited to the above-described one, and the structures of the following embodiments can be given as examples. In the following second to fourth embodiments and comparative examples , the attachment structure of the seal member to the cover member is different from that of the first embodiment, but other configurations are substantially the same as those of the first embodiment. Therefore, detailed description is omitted.

  FIG. 6 partially shows a fuel tank structure 52 according to the second embodiment of the present invention. In the second embodiment, a widened portion 54 that is partially widened toward the outer peripheral side is formed at the upper end of the side cover member 22. Further, an engagement recess 60 that is opened downward is formed on the outer peripheral end 58G side of the seal member 58. The seal member 58 is attached to the cover member 18 by the engagement recess 60 engaging so as to hold the widened portion 54.

  Also in the second embodiment, as in the first embodiment, when the fuel tank 14 is fitted from above into the cover member 18 (see FIGS. 1 and 2) to which the seal member 58 is attached, the seal member. The inner peripheral end 58S side of 58 is in close contact with the side surface 14S of the fuel tank 14. A side gap 44 (insulated air layer 40) is formed between the fuel tank 14 and the cover member 18, and the side gap 44 is sealed with a seal member 58.

  FIG. 7 partially shows a fuel tank structure 72 according to a third embodiment of the present invention. In 3rd Embodiment, the fitting recessed part 74 open | released by the inner peripheral side is formed in the upper end vicinity of the side cover member 22 by curving the board | plate material which comprises the side cover member 22 to an outer peripheral side partially. ing. Further, on the outer peripheral end 78 </ b> G side of the seal member 78, a fitting convex portion 80 that is fitted into the fitting concave portion 74 is formed. Contact pieces 82 for positioning the seal member 78 in contact with the side cover member 22 are formed on the upper and lower portions of the fitting convex portion 80.

  In particular, the fitting convex portion 80 of the third embodiment is formed in a rectangular cross section, and the diagonal length L1 is longer than the height H1 of the fitting concave portion 74. Therefore, even if a force (rotational moment) in the direction of the arrow R1 acts on the seal member 78, the fitting convex portion 80 can be prevented from coming off from the fitting concave portion 74.

  In the third embodiment, as in the first and second embodiments, the fuel tank 14 is fitted from above into the cover member 18 (see FIGS. 1 and 2) to which the seal member 78 is attached. As a result, the inner peripheral end 78S side of the seal member 78 comes into close contact with the side surface 14S of the fuel tank 14. A side gap 44 (insulated air layer 40) is formed between the fuel tank 14 and the cover member 18, and the side gap 44 is sealed with a seal member 58.

FIG. 8 partially shows a fuel tank structure 92 of a comparative example of the present invention. In the comparative example , a fitting recess 94 is formed in the vicinity of the upper end of the side cover member 22, but this fitting recess 94 is opened toward the inner peripheral side and upward. Further, the seal member 98 of the comparative example has a substantially trapezoidal cross section. The width W1 in the cross section of the seal member 98 is longer than the length from the fitting recess 94 to the side surface 14S of the fuel tank 14 in a natural state (a state in which the seal member 98 is not elastically deformed).

In the comparative example having such a configuration, unlike the first to third embodiments, the fuel tank 14 is fitted inside the cover member 18 before the seal member 98 is attached, and then the seal member 98 is fitted. Fit into the mating recess 94 from above. The inner peripheral end 98N side of the seal member 98 is elastically deformed and comes into close contact with the side surface 14S of the fuel tank 14. Also in the comparative example , the side gap 44 (insulated air layer 40) is formed between the fuel tank 14 and the cover member 18, and this air layer is sealed with the seal member 98.

In the comparative example , a member for preventing the seal member 98 from coming off from the fitting recess 94 may be provided.

  Thus, in the present invention, the structure for attaching the seal member to the cover member is not particularly limited, and various attachment structures other than those described above can be adopted.

  Moreover, in each said embodiment, the thing of the structure where the lower surface cover member 20 and the side surface cover member 22 were integrally molded is mentioned as a cover member. When the cover member 18 integrally formed in this way is used, the number of parts is reduced as compared with a separate member, so that it can be configured at a lower cost and an increase in weight can be suppressed.

On the other hand, FIG. 9 shows a fuel tank structure 102 according to a fourth embodiment of the present invention. In the fourth embodiment , the cover member 108 is configured with the lower surface cover member 20 and the side surface cover member 122 as separate bodies, and the lower end of the side surface cover member 122 is fixed to the outer peripheral portion of the lower surface cover member 20. Thus, the side cover member 122 is extended from the lower surface cover member 20. In particular, the side cover member 122 is entirely composed of an elastic member, and a seal member 110 having a certain thickness is integrally formed on the upper portion thereof, similarly to the seal member 28 of the first embodiment. The inner peripheral end 110 </ b> S side of the seal member 110 is in close contact with the side surface 14 </ b> S of the fuel tank 14.

  Even in the fuel tank structure 102 having such a structure, an air layer is formed between the fuel tank 14 and the cover member 108, and this air layer is sealed by the seal member 110. Moreover, although the lower surface cover member 20 and the side surface cover member 122 are separate bodies, since the side surface cover member 122 and the seal member 110 are integrally formed, the number of parts can be reduced in this respect.

  Of course, in the present invention, each of the lower surface cover member, the side surface cover member, and the seal member may be separated.

  Moreover, if the above-described various sealing members seal at least a part of the side gap 44, the air in the heat insulating air layer 40 can be prevented from entering and exiting the outside at the sealed portion. Further, it is not excluded that a member (urethane or the like) for heat insulation is disposed in the lower gap 42 or the side gap 44. For example, urethane is disposed in a part of the lower gap 42 or the side gap 44. However, if the fuel GS in the fuel tank 14 is insulated by making the other portions of the lower gap 42 and the side gap 44 the heat insulating air layer 40, the lower gap 42 and the side gap 44 are all Compared with a configuration in which urethane is disposed on the surface, there is an effect of suppressing an increase in cost and weight.

DESCRIPTION OF SYMBOLS 12 Fuel tank structure 14 Fuel tank 18 Cover member 20 Lower surface cover member 22 Side surface cover member 28 Seal member 28C Corner | angular part 30 Mounting member 36 Slit 38 Air layer 40 Thermal insulation air layer 42 Lower gap 44 Side gap 52 Fuel tank structure 58 Seal member 72 Fuel tank structure 78 Seal member 92 Fuel tank structure 98 Seal member 102 Fuel tank structure 108 Cover member 108 Side cover member 110 Seal member GS Fuel FL Full liquid level TL Contact line

Claims (4)

A fuel tank capable of containing fuel, and
A lower surface cover member that forms a lower gap between the lower surface of the fuel tank and covers the lower surface from below;
A side cover member extending from the lower surface cover member and forming a side gap between the side peripheral surface of the fuel tank and surrounding the side peripheral surface;
It has elasticity and is extended obliquely from the side cover member so as to approach the lower surface cover member as it goes inward from the side cover member, and the side gap between the fuel tank and the side cover member is increased. A sealing member that seals and forms at least a part of the gap as an insulating air layer;
Having fuel tank structure.   2. The fuel tank structure according to claim 1, wherein a contact portion of the seal member with the fuel tank is above a full tank liquid level of the fuel tank. The sealing member is locally narrowed to claim 1 or claim a slit is formed inside the sealing member of the corners of the multi angle shape is formed in a polygonal shape corresponding to the side shape of the fuel tank Item 3. The fuel tank structure according to Item 2 . The fuel tank structure according to any one of claims 1 to 3 , wherein the side cover member is integrally formed with the lower surface cover member.

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