JPH035328B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

This invention relates to improvements in the structure of fuel tanks for automobiles.

2. Description of the Related Art Since a fuel tank for an automobile is installed in a narrow space, it is difficult to secure its capacity. That is, in a bundling vehicle 1 called a so-called one-box car or two-box car as shown in FIG. It is located at the bottom. In this way, when the fuel tank 3 is placed below the floor panel 4, it is placed between the left and right side frames 5, 5 in the vehicle width direction, and the fuel tank 3 is placed between the left and right side frames 5, 5 in the vehicle width direction.
In order to make it removable, its width is smaller than the distance between the side frames 5, 5. In addition, the position of the lower side of the fuel tank 3 has a limit on the departure angle in consideration of running performance on rough roads, and furthermore, in the longitudinal direction of the vehicle, there is a restriction on the rear side of the fuel tank 3 in order to minimize the rear overhang of the body. There is a restriction, and the front position has a differential case (not shown).
Each has its own limitations. Therefore, in order to increase the capacity of a fuel tank, there is no other choice but to increase its external dimensions and to increase the substantial capacity within the fuel tank. Incidentally, in order to prevent an increase in tank internal pressure due to temperature changes, a fuel tank is equipped with a gas-liquid separator that separates fuel vapor from liquid fuel and releases only the vapor to the atmosphere. For example, as shown in FIG.
is equipped with a plurality of partitioned gas-liquid separation chambers 8 and 9 that communicate with each other at an upper end 7, and the upper end 7 is connected to a check valve 10.
The lower end of the one partitioned gas-liquid separation chamber 8 is connected to the upper part of the fuel tank 3 on the side of the gas-liquid separator 6 through the first tube 11.
The lower end of another gas-liquid separation chamber 9 is communicated with the upper part of the fuel tank 3 on the side opposite to the gas-liquid separator 6 via a second tube 12.
By communicating the inner upper space to the outside, the tank internal pressure is released. The check valve 10 is normally connected from a check valve canister (not shown) to the intake system of the engine. Here, if the fuel tank 3 is structured to be filled with liquid fuel, there is a risk that the liquid fuel will overflow into the gas-liquid separator 6 and flow out into the alcohol canister via the check valve 10. Therefore, the maximum amount of fuel injected into the fuel tank 3 is made smaller than the internal volume of the fuel tank 3, and even when the tank is full, a certain amount of space is always formed at the top. It is becoming more and more like this. Therefore, the maximum capacity of the fuel tank 3 is set to a limit value at which liquid fuel does not flow out from the gas-liquid separator 6. In a van-type vehicle 1 as shown in FIG. 1, this gas-liquid separator 6 is positioned as high as possible within the gap S between the inner wall 2A of the passenger compartment 2 and the outer panel 1A of the vehicle body. The maximum amount of fuel in the fuel tank 3 at this time is determined when the fuel liquid level 13 reaches the lower end of the gas-liquid separator 6 when the vehicle 1 is tilted to the maximum extent in the left-right direction of the vehicle body and in the downward direction of the gas-liquid separator 6. The position is set to be lower than the position. However, as described above, there is a limit to how high the position of the gas-liquid separator 6 can be. Therefore, it is not possible to provide a member that partitions the lining 2B, which is continuous above the inner wall 2A, from the space near where the fuel tank 3 is placed. However, there is a problem in that the water enters the vehicle interior 2 through the vehicle interior lining 2B through the inlet opening 14. Furthermore, as mentioned above, since the gas-liquid separator 6 must be placed as high as possible in the narrow space between the vehicle body outer panel 1A and the inner wall 2A of the vehicle interior 2, there is the problem that roughing work is troublesome. There are also points.

[Purpose of the invention]

This invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a fuel tank structure for an automobile that can increase the substantial capacity inside the tank without increasing the external dimensions of the fuel tank. purpose. Another object of the present invention is to provide a fuel tank structure for an automobile that prevents road noise from entering the vehicle interior through a space near the fuel tank. Furthermore, in this invention, the gas-liquid separator can be easily attached and detached.
An object of the present invention is to provide a fuel tank structure for an automobile that can facilitate and shorten assembly work.

[Structure of the invention]

This invention has a gas-liquid separator comprising a plurality of divided gas-liquid separation chambers communicating at the upper end, the upper end of which is open to the atmosphere, and the lower end of one of the divided gas-liquid separation chambers is connected to a first gas-liquid separation chamber. The lower end of another gas-liquid separation chamber is connected to the upper part of the fuel tank on the side opposite to the gas-liquid separator through a second tube. , in a fuel tank structure of an automobile connected to each other, spaced apart on the opposite side to the gas-liquid separator, and when the automobile is tilted to the maximum within a permissible range toward the gas-liquid separator, the fuel tank is full. A sub-tank made of synthetic resin is attached via a bracket to the inside of the fuel tank at a position above the fuel level during tanking, and the first tube is piped with the sub-tank interposed in the middle. The sub-tank achieves the above object by integrally molding a pair of pipe parts into which the inlet tube on the tank inner end side of the first tube and the outlet tube on the gas-liquid separator side are fitted. It is. Further, in the present invention, each of a pair of opposing side walls of the sub-tank is provided with a vertical groove, and the bracket is inserted into the groove of the sub-tank from below, and has approximately the same width as the groove, and has a width substantially the same as that of the sub-tank. a vertical wall portion having approximately the same height; a support portion connected to the lower end of the vertical wall portion and supporting the bottom surface of the sub-tank from below when the vertical wall portion is inserted into the groove; The above object is achieved by comprising a flange portion connected to the upper end and fixed to the back side of the upper surface of the fuel tank. Further, in the present invention, the vertical wall portion of the bracket is provided with a protrusion that resiliently presses against the bottom surface of the groove facing the vertical wall portion when the bracket is inserted into the groove.

[Action of the invention]

In this invention, even if the vehicle leans significantly toward the gas-liquid separator, the sub-tank installed on the opposite side at a position higher than the maximum liquid level allows the air to remain at a position lower than the maximum liquid level. Fuel is prevented from flowing into the liquid separator. Further, the sub-tank is integrally formed with a pair of pipes made of synthetic resin, into which the first tube can be easily fitted, and the connection with the first tube can be easily made. Further, a bracket is elastically attached to the sub-tank with one touch, and by fixing this bracket to the fuel tank, the sub-tank can be easily attached to the fuel tank.

【Example】

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 2 and 3, this embodiment includes two divided gas-liquid separators 18 and 19 that communicate at an upper end 17, and the upper end is opened to the atmosphere via a check valve 20. The lower end of one of the divided gas-liquid separation chambers 18 is connected to the upper part of the fuel tank 23 on the side of the gas-liquid separator 16 via the first tube 21, and In an automobile fuel tank structure, the lower ends of two gas-liquid separation chambers 19 are connected to the gas-liquid separator 16 in the upper part of the fuel tank 23 on the opposite side through the second tube 22. than the full fuel liquid level 24 in the fuel tank 23 when the vehicle M is spaced apart from the vehicle M on the opposite side in the left-right direction, and the vehicle M is tilted toward the gas-liquid separator 16 to the maximum extent within the allowable range. A synthetic resin sub-tank 25 is attached to the inside of the fuel tank 23 at a position above _H1 via a bracket 26, and the first tube 21 is
The sub-tank 25 is interposed in the middle of the piping, and the sub-tank 25 is connected to the inlet tube 21A, which is the tank inner end side portion of the first tube 21, and the gas-liquid separator 16 side portion. A pair of pipe parts 25A and 25B into which the sub-tank 25 side end of a certain outlet tube 21B is fitted are integrally molded. The inlet tube 21A of the first tube 21, which communicates with the sub-tank 25 and the gas-liquid separator 16 side at the upper inner side of the fuel tank 23, has a straight shape. The bracket 26 is attached by welding to the inside of the upper surface of the fuel tank 23, and is attached to the inlet tube 21.
A is connected to a pipe portion 25A formed near the bottom of the sub-tank 25 supported by this bracket 26, and the outlet tube 21B is connected to a pipe portion 25B formed near the top of the sub-tank 25.
It is connected to the. The gas-liquid separator 16 and check valve 20
As shown in FIG. 3, these are preliminarily attached to the fuel inlet pipe 28 by a welding band 27A and a tightening band 27B. Reference numeral 1B in FIG. 2 indicates a car body plate, and this car body plate 1B covers the outside of the lowered gas-liquid separator 16, and covers the upper end of the inner wall 2A rising from the floor panel 4 of the car compartment 2. and the lower end of the vehicle body outer panel 1A, thereby isolating the space around the gas-liquid separator 16 from the space between the vehicle body outer panel 1A and the inner lining 2B.

[Effect of the example]

Next, the operation of the above embodiment will be explained. First, when the automobile M tilts counterclockwise in _FIG . Liquid fuel check valve 2
It does not flow out through 0. Conversely, when the automobile M tilts significantly clockwise in the figure, the gas-liquid separator 16 is at a position H lower than the fuel liquid level 24 when the tank is full. However, as described above, the sub-tank 25 is interposed in the middle of the first tube 21 that communicates the gas-liquid separator 16 with the upper part of the fuel tank 23 on the gas-liquid separator 16 side.
5 is located above the fuel level 24 when the tank is full by H ₁ , so that fuel does not flow into the sub-tank 25 or a small amount of fuel flows into the inlet tube 21A of the first tube 11. The water flows into the sub-tank 25 through. Even if liquid fuel flows into the sub-tank 25, this is just a small amount of the fuel that was in the inlet tube 21A, and the sub-tank 25 will not be filled up and will not reach the gas-liquid separator 16. During so-called figure-eight turns or slalom running, which is the most severe performance test for fuel tanks, the liquid level within the fuel tank 23 is continuously and repeatedly tilted in the clockwise and counterclockwise directions in FIG. In this case, when the left and right tilts occur repeatedly and continuously, when the automobile M tilts clockwise in FIG.
However, when the vehicle body is next tilted counterclockwise, this fuel is returned from the inlet tube 21A to the fuel tank 23. At this time, since the inlet tube 21A is straight, the fuel returns smoothly. Therefore, even during figure-of-eight running or slalom running, there is no leakage of liquid fuel. In the above embodiment, the inlet tube 21A and the outlet tube 21B in the first tube 21
are connected to the bottom and near the top of the gas-liquid separator 16 side end face of the sub-tank 25, respectively; It is fine as long as it is suitable. In the above embodiment, even if the fuel tank 23 is tilted greatly, the liquid fuel will not flow out through the gas-liquid separator 16, so the fuel liquid level when the tank is full is 2.
4 can be set upwards, thus increasing the practical maximum fuel capacity within the tank while maintaining the same external dimensions. Also, if the maximum fuel capacity is the same as before,
The external dimensions of the fuel tank 23 can be reduced, and in this case, the floor panel 4 can be lowered to lower the overall height of the body, and the center of gravity of the vehicle can be lowered to improve handling stability. can be improved. Furthermore, since the position of the gas-liquid separator 16 can be lowered and it can be attached to the fuel inlet pipe 28 in advance, there is no need to assemble the fuel tank 23 and its piping from the passenger compartment 2. , all of which can be done from outside the vehicle. Furthermore, since the gas-liquid separator 16 is made low, as shown in FIG. 2, thereby preventing road noise from entering the vehicle interior 2. Further, in this embodiment, the sub tank 25
is made of synthetic resin, so compared to the metal-molded sub-tank 35 shown in FIG. There is no need to braze the side tube 21A and the outlet tube 21B, therefore, there is no need for a jig or brazing work to be used for brazing work, and there is no need to worry about liquid leakage from the brazed location. There is no need to worry about rust forming at heat-treated locations such as brazing locations, or clogging of the tube due to this rust. In particular, the connection work between the sub-tank 25, the inlet tube 21A, and the outlet tube 21B is performed by connecting the sub-tank 25's pipe portions 25A, 25B
The assembly work can be easily performed by press-fitting the ends of the tube 1A and the outlet tube 21B. Further, in the above embodiment, since both the gas-liquid separator 16 and the check valve 20 are assembled in advance to the fuel inlet pipe 28, the assembly work time can be shortened, and the gas-liquid separator 16 and check valve 20 can be assembled in advance. There is no error in assembly accuracy due to twisting, sagging length, etc. of the hose 33 communicating between the device 16 and the check valve 20, and therefore the assembly accuracy can be improved.

[Second Embodiment] Next, a second embodiment of the present invention shown in FIGS. 6 and 7
An example will be explained. In this second embodiment, each of a pair of opposing side walls 25C and 25D of the sub-tank 25 includes:
A vertical groove 34 is formed in the bracket 26.
is inserted from below into the groove 34 of the sub-tank 25, and connected to a vertical wall portion 36A having approximately the same width as the groove 34 and approximately the same height as the sub-tank 25, and the lower end of the vertical wall portion 36A, When the vertical wall portion 36A is inserted into the groove 34, a support portion 36B that supports the bottom surface of the sub-tank 25 from below is connected to the upper end of the vertical wall portion 36A, and is fixed to the back side of the upper surface of the fuel tank 23. a pair of split brackets 26A, 26 each having a flange portion 36C;
It is composed of B. These split brackets 26A and 26B have the same shape, and are connected to the opposing side walls 25 of the sub tank 25.
It is designed so that it can be inserted into the respective grooves 34 of C and 25D facing each other. These side walls 25C, 2
The groove 34 in 5D has a horizontal cross-sectional shape in which a groove bottom surface 34A is wider than a narrow portion 34B on the outer surface, and an inclined inward wall 34 facing the groove bottom surface 34A.
The vertical wall portions 36A of the divided brackets 26A and 26B are elastically pressed against the groove bottom surface 34A facing the vertical wall portion 36A when inserted into the groove 34. A protrusion 36D is formed, whereby the vertical wall portion 36A is resiliently engaged with the sub-tank 25 while being urged outwardly against the inward wall 34C within the groove 34. Here, the flange portion 36C is the vertical wall portion 36
The width is narrower than that of A, so that it can pass through the narrow portion 34B of the groove 34 in the vertical direction.

[Effect of the example]

Next, the operation of the above embodiment will be explained. Assembling the sub tank 25 to the fuel tank 23 is as follows:
The split brackets 26A and 26B are attached in advance to the groove 34 of the sub-tank 25, and the flange portions 36C of these split brackets 26A and 26B are
This is done by welding to the back side of the upper surface of the fuel tank 23. In this case, the split brackets 26A, 26B are
When the vertical wall portion 36A is inserted from below the groove 34, the projection 36D formed on the vertical wall portion 36A comes into pressure contact with the bottom surface 34A of the groove 34.
A is biased outwardly, which causes the inward wall 34 of the groove 34 to
As a result, the split brackets 26A and 26B can be easily fitted into the sub-tank 25 with one touch without falling off. In this case, since the sub-tank 25 is molded from synthetic resin, the width of the groove 34 varies; Since it is pressed into contact with the two, it will not fall off or cause any looseness between the two. In this embodiment, the bracket 26 is composed of split brackets 26A and 26B, and these split brackets 26A and 26B have vertical wall portions 36A that are movable relative to each other within a certain range in the thickness direction. For example, both of them are supported by the support part 36B.
They may be integrally connected at the tips of the two. Further, although the above embodiment considers the case where the automobile M mainly tilts in the left-right direction, the present invention is not limited to this, and the gas-liquid separator is installed behind or in front of the fuel tank 23, or Of course, this also applies to the case where it is arranged at a position between them.

【Effect of the invention】

Since the present invention is configured as described above, it is possible to increase the substantial maximum fuel capacity within a fuel tank having the same external dimensions, and to reduce the installation height of the gas-liquid separator, thereby improving the ease of assembly. This has the excellent effect of reducing the noise inside the vehicle by closing the route for road noise to enter the vehicle interior.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a fuel tank structure in a conventional van type vehicle, FIG. 2 is a schematic sectional view showing an embodiment of a fuel tank structure for an automobile according to the present invention, and FIG. 3 is a schematic sectional view showing the same embodiment. FIG. 4 is a perspective view showing the sub-tank in the same embodiment, FIG. 5 is a perspective view showing the sub-tank in the same embodiment when the sub-tank is made of metal, and FIG. 6 is the second embodiment of the present invention. FIG. 7 is an exploded perspective view showing essential parts of the embodiment, and FIG. 7 is an enlarged sectional view taken along the - line in FIG. 6. M... Automobile, 16... Gas-liquid separator, 18,1
9... Gas-liquid separation chamber, 20... Check valve, 2
1...First tube, 22...Second tube, 2
1A...Inlet tube, 21B...Outlet tube, 23...Fuel tank, 24...Fuel level when full, 25...Sub tank, 25A, 25B...
Pipe portion, 25C, 25D...Side wall, 26...Bracket, 34...Groove, 36A...Vertical wall portion, 36
B...Support part, 36C...Flange part, 36D...
…protrusion.

Claims (1)

[Scope of Claims] 1. A gas-liquid separator comprising a plurality of divided gas-liquid separation chambers communicating at their upper ends, the upper ends of which are open to the atmosphere, and a lower end of the one divided gas-liquid separation chamber. is the first
The upper part of the fuel tank on the gas-liquid separator side through the tube, and the lower end of another gas-liquid separation chamber
In an automobile fuel tank structure, the fuel tank is connected to the side opposite to the gas-liquid separator at the upper part of the fuel tank through a tube, and the automobile is separated from the gas-liquid separator on the opposite side, and A synthetic resin sub-tank is installed via a bracket inside the fuel tank at a position above the fuel liquid level when the fuel tank is full when the fuel tank is tilted to the maximum within the allowable range toward the separator side, and The tube is piped with the sub-tank interposed therebetween, and the sub-tank is fitted with an inlet tube on the tank inner end side and an outlet tube on the gas-liquid separator side of the first tube. An automobile fuel tank structure is made by integrally molding a pair of pipe parts. 2. The sub-tank is provided with vertical grooves on each of a pair of opposing side walls, and the bracket is inserted into the groove of the sub-tank from below, and has approximately the same width as the groove and approximately the same height as the sub-tank. a vertical wall portion, a support portion connected to the lower end of the vertical wall portion and supporting the bottom surface of the sub-tank from below when the vertical wall portion is inserted into the groove; and a support portion connected to the upper end of the vertical wall portion. 2. The fuel tank structure for an automobile according to claim 1, further comprising: a flange portion fixed to the back side of the upper surface of the fuel tank. 3. The fuel tank structure for an automobile according to claim 2, wherein the vertical wall portion of the bracket is provided with a protrusion that resiliently presses against the bottom surface of the groove facing the vertical wall portion when inserted into the groove.