JP3426438B2 - Fuel tank protection structure - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection structure for a fuel tank. 2. Description of the Related Art When a vehicle travels, tires often cause pebbles and muddy water that has rolled on the road surface to be splashed up, or dust on the road surface to be blown up by wind pressure during traveling. In a car such as a 1BOX car, in which a fuel tank is mounted so as to protrude from the bottom of the vehicle body, pebbles jumped up by tires hit the fuel tank, and mud splashed up by the tires and running wind pressure The dust sowed up adheres to the fuel tank. [0003] In order to protect the fuel tank from splashed pebbles, mud and soaring dust, a fuel tank protection structure is provided with a protector 3 on the front face of the fuel tank 1 as shown in FIG. Proposed. In FIG. 5, the direction of arrow A is forward. The protector 3 has a first protection part 32 for protecting the fuel tank 1 and a second protection part 31 for protecting the inlet pipe 2 for supplying fuel to the fuel tank. ing. Further, the protector 3 is provided with a mounting flange 33 for mounting the protector 3 on the flange 11 formed on the fuel tank 1. [0005] The protector 3 having the above structure absorbs the impact of the pebbles hit by the tire when the pebble collides with the protector 3, and prevents the impact from being transmitted to the fuel tank 1 so that the impact is not transmitted to the fuel tank 1. It is attached so as to form a clearance. The clearance is set wider downward so that the pebbles that have entered the clearance fall to the ground without fail. [0006] However, the formation of a clearance between the fuel tank 1 and the protector 3 as described above causes the following disadvantages. [0007] When the vehicle travels, an airflow is generated in a direction opposite to the traveling direction of the vehicle. At this time, the lower surface of the lower end of the protector 3 and the lower end of the fuel tank 1 opposed thereto are generated. Is depressurized, and a negative pressure is generated. Therefore, as indicated by the arrow in FIG. 6, Karman vortex is generated with the generation of the negative pressure, and the air flow enters the gap 5. Also, the higher the speed, the greater the negative pressure. [0008] As a result, the mud splashed by the tires and the dust soared by the wind pressure during traveling are reduced.
The mud and the dust enter the gap and adhere to the lower surface of the lower end of the protector 3 and the lower end of the fuel tank opposed thereto. The mud and dust adhering and accumulating as described above cause rust and corrosion of the fuel tank 1. The present invention has been conceived in view of the above circumstances, and generates a predetermined or more negative pressure in a gap formed between a fuel tank and a protector attached to the fuel tank. It is an object of the present invention to provide a fuel tank protection structure that can eliminate the cause of rust and corrosion of a fuel tank by preventing mud and dust from adhering to the fuel tank due to the negative pressure. And DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention takes the following technical measures. [0011] That is, the protective structure of the fuel tank according to the present invention includes a protector for covering the front portion of the fuel tank via a predetermined gap, the proteoglycan
Is fixed to the fuel tank at the upper end.
While the entire lower end is spaced from the fuel tank
The rearward of the vehicle body in the above clearance
Are open in series in the width direction of the vehicle body, and a plurality of openings for introducing an airflow from the front into the clearance are provided in a suitable portion of the protector in a line in the width direction of the vehicle body . It is characterized by: According to such a fuel tank protection structure, the airflow introduced from the opening passes through the lower part of the clearance and flows backward along the lower surface of the fuel tank. No negative pressure exceeding a certain level is generated. That is, the mud splashed up by the tire and the dust sowed by the wind pressure during traveling are obstructed by the airflow introduced from the opening and flowing backward through the clearance, and do not enter the clearance. As a result, mud and dust do not adhere to and accumulate on the back surface of the lower end portion of the protector or the lower portion of the fuel tank facing this portion. Therefore, it is possible to prevent the occurrence of rust or corrosion due to the attachment of mud or dust to the fuel tank. The design of the protector can be changed depending on the form of the fuel tank and the mounting position of the inlet pipe. For example, when the inlet pipe is mounted at the rear position of the fuel tank, the protector only needs to have a shape capable of protecting the front part of the fuel tank. When the fuel tank is mounted at the front position of the tank, it is preferable that the fuel tank and the inlet pipe be capable of protecting the front surfaces thereof. Preferably, the opening is provided near the lower end of the protector so that the airflow introduced from the opening passes through the lower part of the clearance and flows backward along the lower surface of the fuel tank. [0015] Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing one embodiment of a protection structure for a fuel tank 1 according to the present invention. The fuel tank protection structure according to the present embodiment includes a protector 3 that covers a lower area of a front portion of the fuel tank 1 and the fuel inlet pipe 2 through a predetermined gap 5. In FIG. 1, the direction of arrow A is forward. The fuel tank 1 is composed of two container-like members provided with flanges 10 and 11 on the periphery of the ends, respectively, and the fuel tank 1 is in the middle state by joining the surfaces of the flanges 10 and 11 of the container-like members. Is formed. A fuel inlet pipe 2 for refueling the fuel tank 1 is attached to a front position of a lower half side surface of the fuel tank 1. The fuel tank 1 and the fuel inlet pipe 2 are made of metal or resin. As shown in FIGS. 2 and 3, the protector 3 is a plate-shaped member made of resin or metal, and has a first protection portion 32 for protecting an area below the front surface of the fuel tank 1. And a second protection portion 31 extending to the first protection portion 32 and protecting the portion 20 of the fuel inlet pipe 2 attached to the fuel tank 1. At the upper part of the protector 3, a mounting flange 33 for mounting to the flange 11 provided on the fuel tank 1 is formed so as to extend therefrom, and near the lower end thereof, an airflow from the front is introduced into the clearance 5. Opening 34
Are provided at a plurality of locations. The protector 3 configured as described above includes:
The upper surface of the mounting flange 33 formed on the protector 3 is connected to the flange 11 provided on the fuel tank 1.
Are joined to each other by a method such as four bolts. As shown in FIG. 4, in the above-described fuel tank protection structure in the present embodiment,
A part of the rearward airflow generated during traveling of the vehicle is introduced into the clearance 5 from the opening 34 and flows rearward from the lower portion of the clearance 5 along the lower surface of the fuel tank 1. ing. The size and number of the openings 34 are set so that a sufficient airflow can be introduced into the gap 5, but the size of each opening is
The size should be such that small pebbles and the like, which are thrown up depending on the tire, cannot pass through. In the fuel tank protection structure configured as described above, the airflow introduced into the gap 5 from the opening 34 flows backward from the lower portion of the gap 5 along the lower surface of the fuel tank 1. Therefore, a large negative pressure exceeding a certain level does not occur in the lower portion of the clearance 5. In other words, the dirt blown up by the tires and the dust blown up by the wind pressure during traveling cause the clearance 5
And is not obstructed by the airflow flowing backward through the gap 5. As a result, mud and dust do not adhere to the back surface of the lower end portion of the protector 3 or the lower portion of the fuel tank 1 facing this portion, and do not accumulate. Therefore, it is possible to prevent the occurrence of rust or corrosion caused by the attachment of mud or dust to the fuel tank 1. Of course, the protection structure for the fuel tank according to the present embodiment is such that pebbles that are thrown up by the tire do not directly collide with the front surface of the fuel tank 1 and the protector 3 is connected between the fuel tank 1 and the fuel tank 1. Is mounted so as to form a predetermined clearance, so that an impact generated when pebble collides with the protector can be absorbed without transmitting to the fuel tank 1. The structure for protecting the fuel tank according to the present invention is not limited to the above-described embodiment, but can be variously modified. For example, in the present embodiment, the first protective member 32 and the second
An opening 34 for introducing an airflow is provided in each of the protection members 31. The opening 34 is provided with the first and second openings.
The protective members 32 and 31 need only be formed on at least one of them, and need not necessarily be formed on both. The form of the fuel tank 1 described in the present embodiment is merely an example, and the present invention is applicable to other forms of the fuel tank 1. For example, when the fuel inlet pipe 2 is attached to the rear position of the fuel tank 1, a fuel tank holding structure including a protector that can protect only the front surface of the fuel tank 1 may be used. Further, in the present embodiment, the protector 3 is provided with mounting flanges for mounting on the flanges 10 and 11 provided on the fuel tank 1. The disposal of the fuel tank 1 to be attached and the method of attaching the protector 3 should be selected, and whether or not the attachment flange 33 is provided is an optional matter. The other points of the present invention are as follows.
In the protection structure of the fuel tank, the above protector 3
It is needless to say that the opening 34 for introducing the airflow is provided near the lower end of the protector 3, and the shape of the protector 3 and the shape, number and size of the opening 34 can be changed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a fuel tank protection structure according to the present invention. FIG. 2 is a plan view of the protector. FIG. 3 is a front view of the protector. FIG. 4 is a diagram showing a cross section taken along a line IV-IV in FIG. 1 and a flow of an airflow. FIG. 5 is an explanatory view of a conventional fuel tank protection structure. FIG. 6 is a diagram showing a cross section taken along line VI-VI of FIG. 5 and a flow of air current. [Description of Signs] 1 Fuel tank 2 Fuel inlet pipe 3 Protector 4 Bolt 33 Mounting flange 34 Opening

Claims (1)

(57) [Claim 1] A protector is provided for covering the front surface of the fuel tank through a predetermined clearance, and the protector is connected to the fuel tank at an upper end portion.
While being fixed, the entire lower end is
The gap between the vehicle and the car
Open the rear part of the body in the width direction of the
Ri, the suitable portion of the protector, characterized in that a plurality of openings for introducing the airflow from the front to the gap is provided <br/> arranged in the width direction of the vehicle body, the fuel tank Protection structure.