JPH036509Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a fuel vapor treatment device (hereinafter referred to as an evaporation system) for a fuel tank mounted on the body of an automobile, etc., and particularly relates to an improvement of a separator. Regarding.

[Conventional technology]

In general, fuel tanks for vehicles such as automobiles have a sealed structure to prevent the fuel vapor containing harmful components such as hydrocarbons evaporated inside the fuel tank from escaping into the atmosphere. The fuel vapor generated inside the engine is guided into the engine's intake system where it is combusted. A system provided for this purpose is called an evaporation system.

As shown in FIGS. 3 and 4, the evaporation system has an evaporation tube 1 for adsorbing fuel vapor and adjusting the pressure inside the fuel tank. The opening at the tip of this evaporation tube is located above the internal space of a cup-shaped separator 3 that opens downward at the ceiling of the fuel tank 2. The separator 3 is caused by fluctuations in the fuel liquid level that occur when the vehicle body vibrates.
This is to prevent water from entering the evaporation tube 1.

That is, the running state of an automobile is not always constant, and it is normal for the vehicle to constantly vibrate vertically and horizontally due to left and right turns, sudden starts and sudden braking, and even driving on rough roads. As the vehicle body changes, the level of the fuel injected into the fuel tank 2 also vibrates, and in some cases, the level of the fuel may reach the opening at the tip of the evaporation tube 1. In order to prevent this, as shown in Figure 3, for example, when the vehicle turns left, the fuel level will tilt as shown by C, but at this time, the fuel level C will not reach the evaporation tube 1. A separator 3 is provided to suppress the liquid level within the separator 3 as shown in D. In other words, a delay time is created and suppressed until the fuel level reaches the tip of the evaporation tube 1 in the separator 3. This delay time is set to be longer than the time required for the vehicle body to return to its normal state.

[Problem that the invention attempts to solve]

Now, in order to fully demonstrate the function of the separator 3, the wall portion of the separator 3 needs to have a sufficient height, and the space inside the fuel tank 1 and the space inside the separator 3 must be in communication with each other under normal conditions. I need to let it happen. Therefore, since the fuel liquid level must be located below the lower end opening of the separator 3, the capacity of the fuel tank 2 is limited. This causes a problem in that sufficient capacity cannot be secured for fuel tanks with strict height restrictions (for example, fuel tanks for front engine/front drive (abbreviated as FF) automobiles).

Therefore, an object of the present invention is to provide a separator that can increase the fuel storage capacity without impairing the function of the separator.

[Means for solving problems]

In order to achieve the above object, the present invention has an opening facing the fuel liquid level in the ceiling of the fuel tank mounted on the vehicle body, and the tip of the evaporation tube is located in the upper part of the internal space. This fuel vapor processing device for a fuel tank equipped with a cup-shaped separator is characterized in that a valley-shaped notch is provided in the wall of the separator in the longitudinal direction of the vehicle body.

[Effect]

According to the above configuration, by providing the valley-shaped notch in the separator wall surface corresponding to the direction of fluctuation of the fuel liquid level in the longitudinal direction of the vehicle body caused by sudden starting or sudden braking of a vehicle, which occurs relatively infrequently, the separator Since the distance between the lower end and the fuel level can be made smaller than before, the storage capacity can be substantially increased compared to a fuel tank of the same size. The reason why the notch is shaped like a valley is that the opening end of the separator needs to correspond to the horizontal inclination of the liquid level in the fuel tank.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings. Note that the same reference numerals are used for the same parts as in FIGS. 3 and 4.

First, let me explain the premise. It has been empirically found that during normal driving, fuel level fluctuations due to turning occur more frequently and over a longer period of time than fluid level fluctuations due to sudden starts and sudden braking. This means that the lower end position (or height of the wall) of the separator wall in the longitudinal direction of the vehicle body does not need to be as low as in the past. On the other hand, only the shaded portion in FIG. 3 is necessary for the separator to perform its function during turning. For this reason, as shown in FIGS. 1 and 2, even if a notch is provided in the wall of the separator located in the longitudinal direction of the vehicle body, the function of the separator will not be impaired in any way.

Based on the above premise, a valley-shaped notch 5 is formed in the wall of the separator 3A according to the present invention in the longitudinal direction of the vehicle body. Notch 5
The reason why is shaped like a valley corresponds to the inverted V-shape that is virtually formed on the separator wall surface when the liquid level of fuel 4 is tilted as shown in Figure 3 (D) and the opposite tilt. This is what I did. In other words, this notch 5
This is because when the lower edge of the separator 3A is along the slope of the liquid level of the fuel 4, it is sufficient to ensure a necessary space (see the shaded area in FIG. 3) within the separator 3A. On the other hand, as shown in FIG. 2, due to this valley-shaped notch 5,
Even if the liquid level A (conventional) of the fuel 4 is raised to the position B (this invention), the space inside the separator 3A and the space inside the fuel tank 2 can be communicated with each other under normal conditions, so that the pressure There is no problem with adjustment.

As mentioned above, the fact that the liquid level of fuel 4 can be raised to position B means that the liquid level A and B
This means that the storage capacity of the fuel tank can be increased by an amount corresponding to the difference between the two.

[Effect of idea]

As described above, according to the present invention, it is possible to provide a separator that can increase the fuel storage capacity without impairing the function of the separator.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing the appearance of the separator according to the present invention, Figure 2 is a sectional view showing the relative relationship between the separator according to the present invention and the fuel liquid level, and Figure 3 is the relative relationship between the conventional separator and the fuel liquid level. FIG. 4 is a cross-sectional view showing the relationship, and a perspective view showing the appearance of a conventional separator. 1... Evaporation tube, 2... Fuel tank, 3A... Separator, 4... Fuel, 5...
...Notch.

Claims (1)

[Scope of utility model registration claim] (1) On the ceiling of the fuel tank mounted on the vehicle body,
In a fuel vapor processing device for a fuel tank equipped with a cup-shaped separator that opens facing the liquid level of the fuel and has a tip of an evaporation tube located in the upper part of the internal space, the separator is arranged in the longitudinal direction of the vehicle body. A fuel vapor processing device for a fuel tank, characterized in that a valley-shaped notch is provided in the wall of the fuel tank. (2) In the device according to claim 1 of the utility model registration, the notch closes the opening of the separator when the vehicle body is tilted in the longitudinal direction, and there is a space between the cutout and the fuel level in normal conditions. 1. A fuel vapor processing device for a fuel tank, characterized in that the fuel tank is opened to a certain position.