JPH1137823A - Fuel level sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel level sensor enabling prevention of a lever from hitching or leaping in the vertical direction and thereby enabling improvement of the durability and measuring accuracy of a level detecting means. SOLUTION: The fuel level sensor, which is provided for a fuel tank T equipped with a film body 1 covering the surface of fuel F at least and is equipped with a lever 4, which detects the position of the surface of the film body 1. The lever 4 is so constructed that the base end part is held swingably through the intermediary of a level detecting means 3 and the fore end part comes into oblique contact with the surface of the film body 1 directly or through the intermediary of an indirect member 2, and the fore end part of the lever 4 is provided with a curved-surface contact part 5, which comes into smooth contact with the surface of the film body 1 or the indirect member 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel level sensor having a lever for detecting a position of an upper surface of a fuel tank provided with a film covering at least an upper surface of fuel.

[0002]

2. Description of the Related Art As a fuel tank provided with a film covering at least the upper surface of a fuel, for example, the fuel tank shown in FIGS. The fuel tank T shown in FIG. 4 covers only the upper surface of the fuel F with the flexible film 1 to prevent the fuel evaporative gas from being discharged into the atmosphere and to reduce the amount of the fuel F during traveling. Swaying is suppressed. Further, the fuel tank T shown in FIG. 5 covers the whole fuel F with the film body 1 so as to suppress the discharge of the fuel evaporative gas and the swing of the fuel F.

As shown in FIGS. 4 and 5, a flat auxiliary measuring plate (indirect member) 2 is provided on the upper surface of the membrane 1, and the position of the auxiliary measuring plate 2 is determined by the fuel level. The detection is performed by the sensor 10.

[0004] The fuel level sensor 10 includes a level detecting means 3 attached to the fuel tank T, and a lever 4 attached to the level detecting means 3. The lever 4 is configured such that a base end portion is swingably supported by the level detecting means 3 and a front end portion is in contact with the measurement auxiliary plate 2 obliquely. Further, the lever 4 is formed by a cylindrical rod, and the tip portion comes into contact with the measurement auxiliary plate 2 by gravity.

In the fuel level sensor 10 configured as described above, the fuel level can be automatically detected by detecting the angle of the lever 4 with the level detecting means 3.

[0006]

However, in the fuel level sensor 10, the measurement auxiliary plate 2 moves forward, backward, left, right, up and down due to the movement of the vehicle, and as shown in FIG. It slides on the measurement auxiliary plate 2. At this time, since the lever 4 is simply formed in a columnar shape, there is a problem that the tip of the lever 2 is easily caught on the measurement auxiliary plate 2. In addition, when such catching occurs, the generated stress is applied to the level detecting means 3 via the lever 4, which adversely affects the durability and measurement accuracy of the level detecting means 3.

Further, when an acceleration in the vertical direction occurs, the lever 4 only contacts the auxiliary measurement plate 2 by gravity, so that the tip of the lever 4 jumps up and down as shown in FIG. Will be. Also in this case, there is a problem that the measurement accuracy is greatly deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to prevent the lever from being caught or jumping up and down, thereby improving the durability of the level detecting means and the measurement accuracy. It is to provide a fuel level sensor that can be achieved.

[0009]

In order to achieve the above object, the present invention provides a fuel tank having a film covering at least an upper surface of a fuel, the fuel tank having a lever for detecting a position of an upper surface of the film. A level sensor, wherein the lever is:
The base end is held swingably via the level detection means,
A tip portion is configured to contact the upper surface of the film body obliquely directly or via an indirect member, and a tip portion of the lever has a curved contact portion that smoothly contacts the upper surface or the indirect member of the film body. Is provided, and the lever is urged by urging means so that the curved surface contact portion comes into contact with the upper surface of the film body or the indirect member.

In the invention configured as described above, since the curved contact portion provided at the tip of the lever comes into smooth contact with the upper surface of the membrane or the indirect member, the fuel swings. Due to the front or back of the membrane body or the indirect member,
Even if it shifts to the left or right, the curved surface contact portion slides smoothly on the upper surface of the membrane or on the indirect member. Therefore, it is possible to prevent the tip of the lever from being caught on the upper surface of the film body or the indirect member, so that it is possible to improve the durability of the level detecting means and the measurement accuracy.

Further, since the urging means for urging the curved surface contact portion so as to contact the upper surface of the film body or the indirect member is provided, the curved surface contact portion is always in contact with the film body even when an acceleration in the vertical direction is generated. In contact with the upper surface or the indirect member. That is, it is possible to prevent the tip of the lever from jumping from the upper surface of the film body or the indirect member, so that the measurement accuracy of the level detecting means can be improved.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. However,
1 shows a first embodiment, FIG. 2 shows a second embodiment, and FIG. 3 shows a third embodiment.

A first embodiment of the present invention will be described with reference to FIG. However, the same reference numerals are given to the same components as those of the conventional example shown in FIGS. 4 and 5, and the description thereof will be omitted.

As shown in FIG. 1, the lever 4 shown in this embodiment has a spherical curved surface contact portion (sphere) 5 at its tip. The curved surface contact portion 5 is always in point contact with the measurement auxiliary plate (indirect member) 2. That is, the curved surface contact portion 5 is always in smooth contact with the measurement auxiliary plate 2 so as not to be caught.

The lever 4 is provided with a predetermined elasticity by a spring (biasing means) 6 so that the curved surface contact portion 5 moves in a direction A (toward the upper surface of the film body 1) with respect to the measurement auxiliary plate 2 side. Powered by force. As shown in FIG. 1, the spring 6 is formed by a tension coil spring. One end of the spring 6 is fixed to the level detecting means 3 and the other end is fixed to the lever 4. By pulling, the curved surface contact portion 5 is always in contact with the measurement auxiliary plate 2. However, the force by the spring 6 is a weak force that prevents the curved surface contact portion 5 from jumping from the measurement auxiliary plate 2, and a force that pushes the measurement auxiliary plate 2 downward to change the upper surface position of the fuel F. Absent.

In the fuel level sensor configured as described above, since the curved surface contact portion 5 that makes point contact with the measurement auxiliary plate 2 is provided at the tip of the lever 4, the measurement auxiliary plate is caused by the oscillation of the fuel F. The curved surface contact portion 5 slides smoothly on the measurement auxiliary plate 2 even if the position 2 moves back and forth and left and right. Therefore, since the tip of the lever 4 does not catch on the measurement auxiliary plate 2, it is possible to improve the durability of the level detecting means 3 and the measurement accuracy.

Further, since the spring 6 for urging the curved surface contact portion 5 toward the measurement auxiliary plate 2 is provided, the curved surface contact portion 5 jumps up from the measurement auxiliary plate 2 even when a vertical acceleration is generated. Nothing. Therefore, the measurement accuracy of the level detection means 3 can be improved. Further, although the force of the spring 6 is weak as described above, the force of the spring 6 exerts a force to press the measurement auxiliary plate 2 to some extent. 2
Can be suppressed, for example, fluctuations that tend to be oblique. Therefore, from this point, the level detecting means 3
Measurement accuracy can be improved.

There is no technical idea that the curved surface contact portion 5 is urged toward the upper surface side of the liquid (the upper surface side of the film body 1 or the measurement auxiliary plate 2 side) by urging means such as a spring 6. is there.

That is, in the case of the conventional fuel tank, the float at the tip of the lever (corresponding to the curved surface contact portion 5 of the present invention)
Is half-immersed in fuel. For example, when the float attempts to jump upward from the fuel due to the vertical vibration of the vehicle, the float is caught by the viscosity of the fuel or the like at the contact point with the fuel and does not jump upward from the fuel. The float is always following the fuel surface.

On the other hand, in the case of the fuel tank T of the present invention, the tip of the lever 4 easily jumps upward from the auxiliary measurement plate 2 due to vertical vibration. Therefore, a mechanism for generating a force toward the measurement auxiliary plate 2, that is, a mechanism including the spring 6, is a completely new one that has not existed in the past.

Next, a second embodiment of the present invention will be described with reference to FIG. However, the same reference numerals are given to the elements common to the first embodiment, and the description will be simplified. The second embodiment differs from the first embodiment in that the spring (biasing means) 7 is constituted by a torsion coil spring.

That is, as shown in FIG.
One end is fixed to the level detection means 3 and the other end is abutted or fixed to the lever 4. By rotating the lever 4 with elastic force, the curved surface contact portion 5 is always in contact with the measurement auxiliary plate 2. It has become.

In the fuel level sensor configured as described above, since the spring 7 is constituted by a torsion coil spring, there is an advantage that the spring 7 can be compactly arranged around the axis of the lever 4. In addition, the same operation and effect as those of the first embodiment are obtained.

Next, a third embodiment of the present invention will be described with reference to FIG. However, the same reference numerals are given to the elements common to the first embodiment, and the description will be simplified. The third embodiment differs from the first embodiment in that the spring (biasing means) 8 is constituted by a compression coil spring.

That is, as shown in FIG.
By fixing one end to the top plate of the fuel tank T and the other end to the lever 4, the curved surface contact portion 5 is urged to the measurement auxiliary plate 2 by the elastic force of compression.

The fuel level sensor constructed as described above has the same operation and effect as the first embodiment.

In each of the above embodiments, the measurement auxiliary plate 2 is provided on the upper surface of the film body 1 and the curved surface contact portion 5 comes into contact with the measurement auxiliary plate 2, but the measurement auxiliary plate 2 is provided. Instead, the curved surface contact portion 5 may directly contact the upper surface of the film body 1. Further, the membrane body 1 may be a bag-like body that accommodates the entire fuel F as shown in the conventional example of FIG.

[0028]

According to the present invention, since the curved surface contact portion provided at the tip of the lever comes into smooth contact with the upper surface of the membrane or the indirect member, the upper surface of the membrane or the upper surface of the membrane is swung by the fuel. Even if the indirect member moves back and forth, left and right, the curved surface contact portion slides smoothly on the upper surface of the membrane or on the indirect member. Therefore, it is possible to prevent the tip of the lever from being caught on the upper surface of the film body or the indirect member, so that it is possible to improve the durability of the level detecting means and the measurement accuracy.

Further, since the urging means for urging the curved surface contact portion toward the upper surface side of the film body is provided, even if a vertical acceleration is generated, the curved surface contact portion always keeps the upper surface of the film body or It comes into contact with the indirect member. That is, it is possible to prevent the tip of the lever from jumping from the upper surface of the film body or the indirect member, so that the measurement accuracy of the level detecting means can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a fuel level sensor shown as a first embodiment of the present invention.

FIG. 2 is a perspective view of a main part of a fuel level sensor shown as a second embodiment of the present invention.

FIG. 3 is a sectional view of a fuel level sensor shown as a third embodiment of the present invention.

FIG. 4 is a sectional view of a fuel level sensor shown as a conventional example.

FIG. 5 is a sectional view of a fuel level sensor shown as another conventional example.

FIG. 6 is a cross-sectional view showing a problem of a conventional fuel level sensor.

FIG. 7 is a sectional view showing another problem of the conventional fuel level sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Membrane body 2 Indirect member (auxiliary measurement plate) 3 Level detection means 4 Lever 6 Urging means (spring) F Fuel T Fuel tank

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shozo Ashizawa 1-7-1 Yokoi, Shimada-shi, Shizuoka Yazaki Keiki Co., Ltd. (72) Inventor Shinji Narama 1-7-1, Yokoi, Shimada-shi, Shizuoka Inside the Company (72) Inventor Hiromasa Takeda 1200, Onjuku, Susono-shi, Shizuoka Prefecture Inside Toyota Motor Corporation (72) Inventor Yoshihiko 1200, Onjuku, Susono-shi, Shizuoka Prefecture Inside Toyota Motor Corporation

Claims (1)

[Claims] 1. A fuel level sensor having a lever for detecting a position of an upper surface of a fuel tank of a fuel tank having a film body covering at least an upper surface of fuel, wherein the lever has a base end for level detection. The lever is swingably held via a means, and a tip portion is configured to abut on an upper surface of the film body obliquely directly or via an indirect member. An upper surface of the film body is provided on a tip portion of the lever. Alternatively, a curved surface contact portion that smoothly contacts the indirect member is provided, and the lever is urged by urging means so that the curved surface contact portion contacts the upper surface of the film body or the indirect member. And a fuel level sensor.