JPH04215523A - Lower structure of car body of automobile - Google Patents

Abstract

PURPOSE:To prevent a fuel tank from damages in a head-on collision of automobiles by obviating a collision between an exhaust pipe and the fuel tank. CONSTITUTION:A guide member 8 is provided between an engine and fuel tank 4. When the engine and an exhaust pipe 2 are moved rearward by a head-on collision of automobiles, an end 7a of a prechamber 7 (or abutting member) is guided to an inclined surface 9 of the guide member 8 to depress downward the exhaust pipe 2. Thus, since the rear part 2' of the exhaust pipe 2 is moved to the lower side of the fuel tank 4, a collision between the fuel tank 4 and exhaust pipe 2 is prevented.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower body structure for an automobile, which can be applied to an automobile in which an intermediate portion of an exhaust pipe is disposed so as to pass near a fuel tank.

0002

2. Description of the Related Art In a car in which the engine is mounted at the front of the car body and the exhaust pipe passes through the vicinity of the fuel tank and opens at the rear of the car body, when the car is in a head-on collision, the engine itself moves rearward. The middle part of the exhaust pipe connected to the engine may collide with the fuel tank, causing damage to the fuel tank.

[0003] A technique for preventing the exhaust pipe from colliding with the fuel tank in the event of a car collision is disclosed in Japanese Utility Model Application Publication No. 56-95928. Its structure is such that a stopper member is fixed to the floor panel and a collision member is fixed to the exhaust pipe, so that the stopper member firmly absorbs the impact force to prevent the exhaust pipe from moving backwards when a car collides. I have to.

0004

SUMMARY OF THE INVENTION In the above-mentioned conventional technology, since the impact force generated when a car collides is received by the stopper member and the abutting member, there are the following problems. That is, since this impact force is a considerably large force, the stopper member and the abutting member are required to have sufficient strength to withstand the impact force. Therefore, these parts are inevitably large and heavy, and the welding between the stopper member and the floor panel and the welding between the abutment member and the exhaust pipe also require similar strength, and the welding work requires a lot of work. The problem is that it requires time. There is a problem in that the impact force is directly transmitted as an impact force to the floor panel to which the stopper member is welded.

[0005] The present invention provides a lower body structure for an automobile that prevents a collision between an exhaust pipe and a fuel tank by releasing the impact force rather than receiving the impact force generated when the car collides. It is.

[0006]

[Means for Solving the Problems] The means according to the present invention for solving the above problems is such that an exhaust pipe whose front end is connected to the engine side passes through the vicinity of a fuel tank disposed at the rear of the vehicle body and extends to the rear of the vehicle body. In a vehicle body lower structure of an automobile in which an engine exhaust system is configured to open, a guide member is positioned between the engine and the fuel tank to guide the movement of the exhaust pipe when it receives force from the front end side. The guide member is fixed in a state separated from the exhaust pipe, the engine side surface of the guide member is inclined downward, and the exhaust system is formed with an abutting portion facing the inclined surface. It is.

[0007]

[Operation] Since the present invention is configured in this manner, when the engine moves backward due to a collision of a car, the guide member is provided separately from the exhaust pipe, so that the guide member is formed in the exhaust system. The contact portion is guided by the inclined surface of the guide member and pushes the exhaust system downward. Since the guide member is located between the engine and the fuel tank, the rear part of the exhaust system that has been pushed downward can be lowered to the bottom of the fuel tank.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, an exhaust pipe 2 whose front end is connected to an engine 1 is bent in the middle into a crank shape, and extends toward the rear of the vehicle body 3 through the vicinity of a fuel tank 4 disposed at the rear of the vehicle body 3. It is provided. Reference numeral 5 denotes a concave tunnel formed to also reinforce the floor panel 6, and a prechamber 7 is disposed within this tunnel 5. In this embodiment, the rear part of the pre-chamber 7 is formed as an abutting portion 7a, but a separate abutting member may be provided as in an embodiment described later. Behind the prechamber 7, a guide member 8 is fixed to the floor panel 6 in a state separated from the exhaust pipe 2. As shown in FIG. 2, this guide member 8 is formed with an inclined surface 9 that is inclined toward the rear side (downward) of the automobile, and as shown in FIG. 3, the exhaust pipe 2 is accommodated in this guide member 8. A concave groove 10 is formed. These inclined surfaces 9, grooves 10,
The vertical flange portion 11 is formed by press working. FIG. 4 shows the guide member 8 installed inside the tunnel 5. In this embodiment, the outer shape of the guide member 8 fits into the inner circumference of the tunnel 5, but the outer shape of the guide member 8 does not necessarily fit into the inner circumference of the tunnel 5. It is not necessary, and the guide member 8 may be provided so as to span the tunnel 5.

FIG. 5 shows another embodiment of the present invention, in which the abutting portion 7a of the prechamber 7 of the previously described embodiment is replaced with an abutment having an inclination approximately equal to the inclination of the inclined surface 9 of the guide member 8. A contact member 12 is fixed to the exhaust pipe 2. 4 and 6, the reference numeral 13 indicates a muffler hanger, in which hanger members 14 and 15 are attached to the exhaust pipe 2 and the guide member 8, respectively, using the guide member 8.

[0010] The operation of this embodiment configured as described above will be explained next. When the engine 1 moves rearward due to a head-on collision of the automobile, the exhaust pipe 2 also moves rearward. When the exhaust pipe 2 moves rearward in this way, since the guide member 8 is provided separately from the exhaust pipe 2, only the exhaust pipe 2 moves rearward, and as shown in FIG. The portion 7a is guided by the inclined surface 9 of the guide member 8 and pushed down as indicated by 7'. Since the guide member 8 is located between the engine 1 and the fuel tank 4, the rear end 2' of the exhaust pipe 2 pushed downward moves to the bottom of the fuel tank 4. This rear 2'
does not hit the fuel tank 4.

When the exhaust pipe 2 is provided with the abutting member 12 as shown in FIG.
is pushed down to move the rear end of the exhaust pipe 2 to the lower side of the fuel tank 4, so that the rear end of the exhaust pipe 2 does not hit the fuel tank 4. Furthermore, even if the muffler hanger 13 is provided as shown in FIGS. 4 and 6, the sliding force between the inclined surface 9 of the guide member 8 and the end 7a of the prechamber 7 or the contact member 12 during a collision may cause the muffler hanger 13 to is broken, and it becomes possible to move the rear end of the exhaust pipe 2 to the lower side of the fuel tank 4 in the same way.

The present invention does not absorb the impact force at the time of a collision as described above, but instead absorbs the impact force by sliding between the inclined surface 9 of the guide member 8 and the contact portion 7a of the prechamber 7 or the contact member 12. Since the impact force is released, the impact force on the floor panel 3 is reduced.

[0013]

[Effects of the Invention] As detailed above, according to the present invention, a guide member is provided between the engine and the fuel tank and separated from the exhaust pipe, and is provided on the inclined surface of the guide member and the exhaust system. Since the exhaust pipe, which moves rearward in the event of a collision, is pushed down via the contact portion, it is possible to prevent the exhaust pipe from hitting the fuel tank, thereby preventing damage to the fuel tank. In addition, since the impact force is released by sliding between the inclined surface of the guide member and the abutment part provided on the exhaust system, the impact force at the time of a car collision is not transmitted to the floor panel, and
Since the impact force is released by the sliding, the guide member and its attachment are not required to have sufficient strength to withstand the impact force, and the guide member can be made lightweight and easily installed.

[0014]

[Brief explanation of the drawing]

FIG. 1 is a plan view of a lower structure of an automobile showing an embodiment of the present invention.

FIG. 2 is a front view showing the main parts of FIG. 1;

FIG. 3 is a perspective view of the guide member of FIG. 1;

FIG. 4 is a vertical cross-sectional view taken along line AA in FIG. 1 when a muffler hanger is attached.

FIG. 5 is a front view of main parts in another embodiment of the present invention.

FIG. 6 is a front view of that of FIG. 4;

[Explanation of sign]

1 Engine 2 Exhaust pipe 4 Fuel tank 7 Prechamber 7a Contact part 8 Guide member 9 Sloped surface

Claims (1)

[Claims] [Claim 1] A lower body structure for an automobile in which an engine exhaust system is configured such that an exhaust pipe whose front end is connected to the engine side passes near a fuel tank disposed at the rear of the vehicle and opens to the rear of the vehicle. A guide member that guides the movement of the exhaust pipe when it receives a force from the front end side is located between the engine and the fuel tank and fixed in a state separated from the exhaust pipe, and the guide member is attached to the engine side surface of the guide member. A lower body structure for an automobile, characterized in that the exhaust system is inclined downward, and the exhaust system is formed with an abutting portion facing the inclined surface.