JP2012141290A - Structure of fuel tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a fuel tank having a liquid level sensor that is soft and flexible, and stands by itself in a liquid in the tank.SOLUTION: A liquid level sensor 14 is made of a material having flexibility. A lower part of the liquid level sensor 14 is fixed onto a pump module 16 and held along the outer peripheral surface of the pump module 16 as a fixed part 14A. A part of the liquid level sensor 14 protruded higher than the pump module 16 is a movable part 14B that can be elastically deformed by the flexibility of the liquid level sensor 14. In assembly work, even when the upper end of the liquid level sensor 14 interferes with a protrusion 26, the liquid level sensor 14 bends and passes below the protrusion 26 as shown in Fig. 2(B). Because the movable part 14B, which is a part that is not joined with the pump module 16, that is, the part protruded higher than the pump module 16, is capable of elastic deformation as mentioned above. Accordingly, the assembly work can be performed.

Description

  The present invention relates to a fuel tank structure, and more particularly to a fuel tank structure of a tank applied to a fuel tank mounted on a vehicle such as an automobile.

  2. Description of the Related Art Conventionally, there are various types of fuel amount measuring devices provided in a fuel tank of an automobile or the like. As one of them, a fuel electrode is measured by using a vertically long detection electrode (sensor) extending in the vertical direction of the vehicle body. The structure which detects the position which a detection electrode contacts is detected, and detects a liquid level is employ | adopted (for example, refer patent document 1).

  At this time, as shown in FIG. 7, in the comparative example in which the liquid level reaches above the opening (insertion port) of the fuel tank, the liquid level above the opening of the fuel tank is detected. In order to do this, it is necessary to extend the upper end of the liquid level sensor above the opening. Such a liquid level sensor may include a circuit portion or the like in a pump module that is installed in a fuel tank, for example, and the sensor portion may be integrated with the pump module to reduce the number of parts and assembly man-hours.

  For example, when an electrode such as a film is used in an electrostatic liquid level sensor, even if the electrode is simply self-supported in the liquid, when the fuel fluctuates according to the movement of the vehicle, it is easily deformed due to the influence. Therefore, accurate liquid level detection may be difficult.

  Therefore, a configuration is adopted in which a flexible electrode is inserted into a hard pipe or the like to prevent excessive deformation in the liquid (see, for example, Patent Documents 2 and 3). Or the structure which encloses a film-form electrode in the protective pipe formed with the raw material which can deform | transform is employ | adopted (for example, refer patent document 4).

JP 2010-025782 A JP-A-2005-351689 Japanese Patent Laid-Open No. 05-223624 JP-T-2006-523830

  However, when the liquid level sensor is sealed in a rigid body or a case made of a rigid body as in the configurations described in Patent Documents 2 and 3, when installing the pump module in the fuel tank, depending on the internal structure of the tank, the ceiling back portion, etc. The liquid level sensor may interfere with the inner wall of the tank, which may hinder the assembly work. For example, even if the electrode portion of the liquid level sensor is a flexible material such as a film, the shape of the case must be matched to the shape of the tank when used in a hard case.

  As in the invention described in Patent Document 4, although the assembly itself is possible if the electrode is enclosed in a protective pipe formed of a deformable material, the electrode shape after the assembly can be deformed. It is not secured and needs to be held in some way. For this reason, as compared with a configuration in which a single electrode such as a film is installed in the tank, there is a risk of cost increase due to a complicated internal structure, an increase in the number of parts, an increase in assembly man-hours, and the like.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a fuel tank structure provided with a liquid level sensor that is flexible and deformable and is self-supporting in the liquid in the tank.

  The fuel tank structure according to claim 1 is provided in a vehicle, and includes a fuel tank provided with an insertion port provided on the upper side surface of the vehicle body, and a convex portion protruding around the insertion port toward the lower side of the vehicle body, The pump module installed in the fuel tank and a sheet-like flexible material are disposed so as to be longitudinal in the vertical direction of the vehicle body, and the cross section perpendicular to the longitudinal direction is curved or bent, And a liquid level sensor fixed to the pump module on the lower end side of the vehicle body so that the upper end is positioned on the upper side of the vehicle body relative to the lower end of the vehicle body of the convex portion.

  In the fuel tank structure according to claim 1, when the pump module is installed in the fuel tank, the liquid level sensor provided integrally with the pump module has flexibility, and thus interferes with the convex portion. Can be assembled by bending once. Moreover, since the cross section orthogonal to the longitudinal direction has a curved or bent shape, the liquid level sensor can maintain its shape even when the fuel fluctuates.

  According to a second aspect of the present invention, there is provided the fuel tank structure according to the first aspect, wherein at least a part of the outer peripheral surface of the pump module is cylindrical when viewed from the vertical direction of the vehicle body, and the liquid level sensor is cylindrical. It is fixed in close contact with the outer peripheral surface.

  In the fuel tank structure according to claim 2, since the liquid level sensor curved along the outer peripheral surface of the pump module has an arc-shaped cross section, the shape can be maintained withstanding the oscillation of the fuel. it can.

  According to a third aspect of the present invention, there is provided the fuel tank structure according to the first aspect, wherein the liquid level sensor has a V-shaped cross section orthogonal to the longitudinal direction, and the first side forming the V shape. And the second side is fixed to the surface of the pump module.

  In the fuel tank structure according to the third aspect, since the cross section of the liquid level sensor is V-shaped when viewed from the vertical direction of the vehicle body, the shape can be maintained withstanding the oscillation of the fuel.

  The fuel tank structure according to claim 4 is the structure according to any one of claims 1 to 3, wherein the liquid level sensor is required for the fuel tank in a state where the insertion port of the fuel tank is closed with a lid. It is integrated with the pump module and the lid so as to be installed at the position.

  In the fuel tank structure according to the fourth aspect, the pump module and the liquid level sensor can be installed at predetermined positions in the fuel tank by closing the insertion port with a lid.

  As described above, the fuel tank structure according to the present invention has an excellent effect that the liquid level sensor is flexible and deformable and can stand alone in the liquid in the tank.

It is a sectional side view which shows the fuel tank provided with the fuel tank structure which concerns on embodiment of this invention. It is a sectional side view which shows the deformation | transformation of the liquid level sensor at the time of installation of the fuel tank structure which concerns on 1st Embodiment shown in FIG. It is a top view which shows the fuel tank structure which concerns on 1st Embodiment shown in FIG. It is a side view which shows the example of a shape of the liquid level sensor of the fuel tank structure which concerns on 1st Embodiment of this invention. It is a top view which shows the fuel tank structure which concerns on 2nd Embodiment of this invention. It is an expansion perspective view which shows the part of the fuel tank structure which concerns on 1st Embodiment of this invention. It is a sectional side view which shows a deformation | transformation of the liquid level sensor at the time of installation of the fuel tank structure which concerns on a comparative example. It is a top view which shows the fuel tank structure which concerns on a comparative example.

  <Structure>

  A fuel tank structure according to a first embodiment of the present invention will be described with reference to FIGS. In the figure, the arrow UP indicates the upward direction of the vehicle body.

  As shown in FIG. 1, in this fuel tank structure, a fuel amount measuring device 12 is provided inside the fuel tank 10. The fuel amount measuring device 12 is disposed along the outer wall 20 at the bottom of the fuel tank 10.

  The fuel tank 10 is a container having a substantially box shape as shown in FIG. 1, and its shape is determined by the shape of a vehicle body or the like to be installed and the component arrangement. The material of the fuel tank 10 is selected in consideration of resistance to corrosion by fuel (gasoline etc.), mechanical strength, impact resistance and safety in the event of a collision.

  An insertion port 22 is provided on the upper side of the vehicle body of the fuel tank 10 and is sealed with a lid portion 28 serving as a lid for closing the insertion port 22 from the outside so that the fuel inside does not leak out. The insertion port 22 protruding in a cylindrical shape in the upward direction of the vehicle body is sealed with a lid portion 28, and the lid portion 28 is fixed by a screw lid 120 that is screwed with a male screw provided on the outer peripheral surface of the insertion port 22.

  At this time, if the insertion port 22 protrudes from the box-shaped fuel tank 10, space efficiency may be lowered when assembled to the vehicle body. Therefore, the insertion port 22 should be provided so as to be submerged inside the fuel tank 10. desirable. In this case, it is necessary to provide a space in the fuel tank 10 where the insertion port 22 and the screw lid 120 can be cleared.

  Accordingly, a concave portion 24 having a concave outer surface is formed on the upper surface of the vehicle body of the fuel tank 10, and an inner portion of the concave portion 24 is formed as a convex portion 26 protruding toward the lower side of the vehicle body inside the fuel tank 10. Therefore, as the fuel tank 10 is filled with fuel, the liquid level F exceeds the height of the lower end of the vehicle body of the convex portion 26, and the lower portion of the vehicle body of the convex portion 26 is immersed in the fuel.

  That is, the full tank liquid level (see the liquid level F in FIG. 1) of the fuel tank 10 is set above the lower end of the convex portion 26. The fuel tank 10 has a full tank liquid level as described above, thereby restricting the total amount of fuel that enters the fuel tank 10 and securing a vapor layer.

  The above-described insertion port 22 is provided on the upper side of the vehicle body of the fuel tank 10, and the insertion port 22 is used for inserting the pump module 16. A connecting member 18 extends on the back side of the lid 28 that closes the insertion port 22 from the outside, that is, the surface facing the inside of the fuel tank 10, and the pump module 16 is integrally coupled to the lid 28. .

  The pump module 16 is substantially cup-shaped, and a fuel hose (not shown) is provided inside. The fuel hose communicates the inside of the pump module 16 and the outside of the fuel tank 10 and feeds the fuel to the outside of the fuel tank 10 by a fuel pump (not shown). The opening of the fuel hose provided inside the pump module 16 opens near the bottom surface of the fuel tank 10, and fuel remains in the pump module 16 even when the fuel remaining in the fuel tank 10 is low. It is possible to feed.

  As shown in FIG. 1, a long liquid level sensor 14 that is elongated in the vertical direction of the vehicle body is provided on the side surface (outer peripheral surface) of the pump module 16 in the fuel tank 10.

  For example, as shown in FIG. 4, the liquid level sensor 14 has a configuration in which an electrode 14D is provided on the surface of a base 14C formed of a flexible sheet-like insulator such as a resin film having a longitudinal direction in the vertical direction of the vehicle body. Is done. The liquid level sensor 14 is formed in a flexible sheet shape as a whole, and has a long shape arranged along the vertical direction of the vehicle body as will be described later. Such a liquid level sensor 14 detects the remaining amount of fuel remaining in the fuel tank 10 based on, for example, the capacitance of the electrode 14D that varies depending on the length of the portion in contact with the fuel such as gasoline. . The electrode 14D is not a simple ladder-like wiring, and as shown in an enlarged view in FIG. 4, the electrodes 14D are arranged in a comb shape so as to overlap each other and are not electrically connected. Is forming.

  As a method of electrically detecting the liquid level, for example, there is a method of measuring the capacitance between the electrodes 14D. When the fuel in the fuel tank is reduced (eg, exhausted), the space between the electrodes 14D becomes occupied by what was previously occupied by the fuel, so the capacitance decreases. Therefore, by detecting the decrease in the capacitance, it is possible to detect that the fuel in the fuel tank 10 has decreased (for example, the fuel tank 10 has become empty). Alternatively, at this time, by providing a reference measurement unit provided in the air in advance and a reference measurement unit that is always present in the liquid, and using the detected value as a reference to compare the measurement values, In addition, accurate detection can be performed.

  The electrode 14D is electrically connected to the outside through a terminal 14E provided at the end of the liquid level sensor 14. For example, the liquid level detected by an electric circuit provided outside is provided outside the fuel tank 10 as fuel amount information. Is transmitted to.

  FIG. 3 shows a plan view of the pump module 16 shown in FIG. 1 as viewed from above the vehicle body.

  As shown in FIG. 3, at least a part of the outer peripheral surface of the pump module 16 has a cylindrical shape with a radius R, and the liquid level sensor 14 is attached to the outer peripheral surface of the cylindrical shape. It is integrated along the line. In other words, the liquid level sensor 14 has a shape having an arc-shaped cross section with a radius R in a plan view (a cross-sectional view orthogonal to the longitudinal direction) viewed from the upper side of the vehicle body. .

  More specifically, as shown in FIG. 1, the liquid level sensor 14 includes a fixed portion 14 </ b> A for the pump module 16 and a movable portion 14 </ b> B extending further to the vehicle body upper side than the vehicle body upper end of the pump module 16. . The fixed portion 14A is a part on the lower end side of the liquid level sensor 14, and is fixed in close contact with the portion having an arc shape with the radius R on the outer peripheral surface of the pump module 16 by sticking or the like. The liquid level sensor 14 may be curved by being fixed to the outer peripheral surface of the pump module 16, or may be previously curved in an arc shape having a radius R. In any case, the fixed portion 14A and the movable portion 14B have an arc shape as described above in a cross section perpendicular to the longitudinal direction.

  The movable part 14B of the liquid level sensor 14 is continuous with the upper side of the fixed part 14A in the vehicle body, and the upper side of the vehicle body is positioned above the lower side of the vehicle body of the convex portion 26. That is, the vehicle body upper end of the liquid level sensor 14 itself is positioned above the vehicle body lower end of the convex portion 26 than the vehicle body lower end.

<Action>

  Next, the operation of this embodiment will be described.

  As shown in FIG. 1, when fuel is filled in the fuel tank 10, the liquid level sensor 14 detects the liquid level (liquid level F) up to the full tank liquid level. It extends to a position higher than the direction height.

  As described above, the insertion port 22 is hermetically sealed with the lid portion 28, and the shape of the insertion port 22 is fixed because the lid portion 28 is fixed by the screw lid 120 that is screwed with the male screw provided on the outer peripheral surface of the insertion port 22. Is circular in plan view. Therefore, in order to maximize the size of the pump module 16 that can pass through the insertion port 22, a cylindrical shape that is circular in plan view is desirable. After the pump module 16 having a cylindrical shape is passed through the insertion port 22 in the vertical direction of the vehicle body, the pump module 16 coupled to the lid portion 28 by the connecting member 18 is sealed by sealing the insertion port 22 with the lid portion 28. It can be fixed in the fuel tank 10.

  At this time, as shown in FIG. 2A, considering the case where the pump module 16 coupled with the lid portion 28 and the connecting member 18 is moved to a predetermined position, the lid portion 28 is moved in the direction of the white arrow in the figure. If it slides, the pump module 16 will move to a predetermined position.

  However, since the liquid level sensor 14 needs to detect the liquid level up to the full liquid level as described above, it needs to be extended to a position higher than the convex portion 26 (upper side of the vehicle body) as shown in FIG. Therefore, if the pump module 16 is moved to the position shown in FIG. 1, the liquid level sensor 14 interferes with the convex portion 26 as shown in FIG.

  At this time, when the liquid level sensor 114 is formed in a plate shape with a rigid body such as metal or hard plastic as in the comparative examples shown in FIGS. 7 and 8, for example, the upper end of the liquid level sensor 114 interferes with the convex portion 126. By doing so, there is a possibility that the above assembling work may be hindered. That is, there is a possibility that the liquid level sensor 114 cannot penetrate under the convex portion 126 and the liquid level sensor 114 cannot be installed at a predetermined position.

  On the other hand, the liquid level sensor 14 of the present embodiment is formed of a flexible material, and the lower part of the vehicle body is held as a fixed part 14A along the outer peripheral surface of the pump module 16. . On the other hand, a portion of the liquid level sensor 14 that protrudes above the vehicle body from the pump module 16 can be elastically deformed by the flexibility of the liquid level sensor 14 as a movable portion 14B.

  As a result, as shown in FIG. 2 (A), when the pump module 16 coupled with the lid portion 28 and the connecting member 18 is moved to a predetermined position, the upper side of the liquid level sensor 14 on the vehicle body side. Even if the end interferes with the convex portion 26, the portion that is not joined to the pump module 16, that is, the movable portion 14B that protrudes to the upper side of the vehicle body from the pump module 16, can be elastically deformed as described above. As shown in FIG. 2 (B), the liquid level sensor 14 is bent and clears by passing through the lower side of the vehicle body of the convex portion 26, so that the assembling work can be performed. Therefore, in this fuel tank structure, when the lid 28 is moved to a position where the lid 28 closes the insertion port 28, the pump module 28 and the liquid level sensor 14 are respectively installed at predetermined positions.

  Further, the liquid level sensor 14 is bent into a shape along the outer peripheral surface of the pump module 16. That is, as shown in FIG. 3, when the outer peripheral surface of the pump module 16 is a substantially cylinder having a radius R, the liquid level sensor 14 also has an arc shape having a radius R in the plan view as viewed from the vertical direction of the vehicle body. It is a part of a cylindrical shape having a cross section.

  As a result, the liquid level sensor 14 can maintain the strength and rigidity of the movable portion 14B. That is, by setting the radius R according to the length of the movable portion 14B in the vehicle body vertical direction (sensor offset amount) and the width d of the liquid level sensor 14 shown in FIG. 3, the inside of the fuel tank 10 generated during cornering or the like is set. It can withstand the fuel swaying and maintain an upright posture in the vertical direction of the vehicle body and correctly detect the liquid level.

  That is, when the sensor offset amount increases, the radius R (= curvature radius) is decreased to increase the rigidity of the liquid level sensor 14 and to withstand the fuel oscillation. Similarly, in the case of a shape having a large width d, the rigidity of the liquid level sensor 14 can be increased by reducing the radius R, so that the fuel can swing.

  Regarding the fixing of the liquid level sensor 14, in addition to the method of adhering to the outer peripheral surface of the pump module 16, for example, as shown in FIG. It is good also as a structure which fixes to the outer peripheral surface of the pump module 16 by providing the holding part 17B to hold | grip in the outer peripheral surface of the pump module 16, and fitting the liquid level sensor 14. FIG.

Second Embodiment

  Next, a fuel tank structure according to a second embodiment of the present invention will be described with reference to FIG. In addition, the same member as 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits the description.

  As shown in FIG. 5, the liquid level sensor 15 of the fuel amount measuring device 12 constituting the fuel tank structure according to the present embodiment is at an angle θ in a plan view (a cross-sectional view orthogonal to the longitudinal direction) viewed from the vehicle body vertical direction. A columnar structure having a substantially V-shaped cross section is formed. That is, the liquid level sensor 15 has a first side 15A and a second side 15B that are V-shaped in a cross-sectional view orthogonal to the longitudinal direction.

  On the other hand, a part of the outer surface of the pump module 16 is two planes 16A and 16B that intersect at a predetermined angle θ. The liquid level sensor 15 is fixed to the flat surface 16A whose first side 15A forms the outer surface of the pump module 16, and the second side 15B is fixed to the flat surface 16B which forms the outer surface of the pump module 16. It is fixed by.

  Even in the V-shape described above, the liquid level sensor 15 can maintain the strength of the movable part as in the first embodiment. That is, the angle θ is set according to the vehicle body vertical length (sensor offset amount) of the movable part not in contact with the two flat surfaces provided on the outer peripheral surface of the pump module 16 and the width d of the liquid level sensor 15 shown in FIG. By setting, it is possible to withstand the oscillation of the fuel inside the fuel tank 10 that occurs during cornering or the like, maintain an upright posture in the vertical direction of the vehicle body, and correctly detect the liquid level.

  In the present embodiment, unlike the first embodiment, the cross section in the plan view of the liquid level sensor 15 viewed from the vertical direction of the vehicle body is not an arc shape but a substantially V shape. Moreover, the outer peripheral surface of the pump module 16 has a substantially cylindrical shape as shown in FIG. 5, for example, and the liquid level sensor 15 is provided on the outer peripheral surface of the pump module 16 along the V-shape 16A. , 16B abuts against the pump module 16 only.

  As a result, in this embodiment, the liquid level sensor 15 can be easily fixed (adhesion, screwing, etc.), the center alignment in the width d direction can be accurately performed, and, for example, linear slits 2 that intersect at an angle θ. The book also has features such as the ability to fix the lower end of the car body.

  Also in this embodiment, the fuel generated at the time of cornering or the like is set by setting the angle θ according to the length of the movable part in the vehicle body vertical direction (sensor offset amount) and the width d of the liquid level sensor 15 shown in FIG. The liquid level sensor 15 can withstand the fuel oscillation in the tank 10 and can maintain an upright posture in the vertical direction of the vehicle body, so that the liquid level can be detected correctly.

  That is, when the sensor offset amount increases, the angle θ (= V scissor angle) is decreased to increase the rigidity of the liquid level sensor 15 and to withstand the fuel oscillation. Similarly, the rigidity of the liquid level sensor 15 can be increased by reducing the angle θ for the difference in the shape having a large width d, so that it can withstand the oscillation of the fuel.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. For example, the liquid level sensor 15 may be configured such that the first sides 15A and 15B are fixed to a cylindrical outer peripheral surface of the pump module 16 as shown in FIG. Further, for example, the pump module 16 is not limited to the configuration arranged at the bottom of the fuel tank 10.

  Further, it goes without saying that the scope of rights of the present invention is not limited to these embodiments and can be implemented in various modes without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Fuel tank 12 Fuel quantity measuring device 14 Liquid level sensor 14A Fixed part 14B Movable part 15 Liquid level sensor 15A 1st edge | side 15B 2nd edge | side 16 Pump module 17 Grasping part 18 Connecting member 20 Outer wall 22 Insertion port 24 Concavity part 26 Convex part 28 Lid 120 Screw lid F Liquid level R Radius θ Angle

Claims (4)

A fuel tank provided in a vehicle and provided with an insertion port provided on an upper side surface of the vehicle body, and a convex portion protruding around the insertion port on the vehicle body lower side,
A pump module installed in the fuel tank;
It is made of a sheet-like flexible material, and is arranged so as to be longitudinal in the vertical direction of the vehicle body. The cross section orthogonal to the longitudinal direction is curved or bent, and the upper end of the vehicle body is lower than the lower end of the vehicle body of the convex portion. A liquid level sensor fixed to the pump module on the lower end side of the vehicle body so as to be positioned on the upper side of the vehicle body,
With fuel tank structure. The pump module has a cylindrical shape at least a part of the outer peripheral surface when viewed from the vertical direction of the vehicle body,
The fuel tank structure according to claim 1, wherein the liquid level sensor is fixed in close contact with the cylindrical outer peripheral surface.   2. The liquid level sensor has a V-shaped bent cross section perpendicular to the longitudinal direction, and the first side and the second side forming the V shape are fixed to the surface of the pump module. The fuel tank structure described in 1.   The said liquid level sensor is integrated with the said pump module and the said lid | cover so that the said insertion port of the said fuel tank may be installed in the predetermined position with respect to the said fuel tank in the state which plugged up with the lid | cover. 4. The fuel tank structure according to any one of 3 above.

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