JPH03227725A - Exhauster for vehicle - Google Patents

Abstract

PURPOSE:To prevent a fuel tank from being damaged owing to the deformation of a center pipe by making up the center pipe for an exhauster out of 2 pieces of pipes the opposite cut-off sections of which are made slant, joining the opposite sections by the use of flanges, and concurrently allowing flange fastening bolts to be loosened so as to be parted when the flanges are subjected to impact force. CONSTITUTION:In a center pipe 3 between a converter 1 for purifying gas from an exhauster and a muffler 2, each slant cut-off section with a specified angle alpha is formed at the middle of the center pipe, and each flange 14 and 15 is so provided as to be conformed with the cut-off surface 19 of the slant cut-off section. In addition, the flange 15 is formed with a seal surface 20 which is projected out of the fastening surface, a gap of a dimension C is formed between the mating surfaces of the flanges 14 and 15, and the fastening force of each bolt 22 is so adjusted that the joint surfaces of the flanges 14 and 15 are stepped off because of impact force at the time of the head-on collision of a vehicle. Furthermore, 2 bolt holes 16 and 17 are bored at the positions holding an opening for the center pipe 3 in each flange 14 and 15, and each one of the bolt holes 17 and 18 is formed with a slit 18.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in an exhaust system for an automobile.

(Prior Art) In a car accident, if a fuel tank is damaged and fuel leaks, it can cause a fire. One of the causes of this fuel tank damage is that the center pipe, which is an automobile exhaust system, is deformed by the impact force of an automobile accident and breaks through the fuel tank.

As shown in FIG. 9, in a conventional automobile exhaust system, a center pipe 3 between a converter 1 and a muffler 2 is connected by a flange 4 provided perpendicularly to the axis of the center pipe 3. In addition, as shown in Figure 10, the converter l
There is also one in which a flexible vibe 5 is provided in the center pipe 3 between the muffler 2 and the muffler 2. Also, in order to proactively prevent damage to the fuel tank, the first step is to prevent damage to the fuel tank! As shown in the figure, a protective cover 7 is provided to cover the bottom of the fuel tank 6, and as shown in FIG. In some cases, an inclined surface 8 is formed on the front surface of the fuel tank 6 to prevent the center pipe 3 from colliding with the front surface of the fuel tank 6 so that the deformed and moved center pipe 3 can escape as shown by arrow B.

(Problems to be Solved by the Invention) In the conventional automobile exhaust system described above, the one shown in FIG. 9 has the following first problem. In the automobile exhaust system, a flange lO of a front vibe 9 is connected to an engine (not shown), and a converter 1. The mufflers 2.2 are supported on the vehicle body by rubber mounts +1, 12, and 13, respectively. When a car collides head-on and the engine (not shown) moves in the direction of the arrow Ah, an impact force acts on the connection surface of the flange 4 in the axial direction of the center vibe 3, so that the flange 4 does not come off and the center vibe 3 is deformed and moved as shown in 3. Rubber mount 11.
12 comes off and the center vibe 3 breaks through the fuel tank 6 as shown in the figure. In addition, in the case shown in Fig. 1O, there is no problem if the amount of deformation movement of the center vibrator 3 due to the ifi impact force is within the absorption range of the flexible vibe 5; If it exceeds , the same problem as explained in FIG. 9 will occur. Further, when the flexible vibrator 5 is used, there is a problem that the number of parts increases and the number of man-hours required to assemble them increases accordingly, resulting in high costs.

Next, as shown in Figure 1+, a protective cover attached to the bottom of the fuel tank also has the problem of increasing the number of parts, increasing costs, and increasing the number of overlapping parts.3 Also, as shown in Figure 12, This is effective in the case of an inside collision of a car, but in the case of a rear-end collision (not an i-effect), in this case there is still the problem that the center vibrator deforms and moves, damaging the fuel tank. The present invention provides an automatic 1F exhaust system that prevents damage to the fuel tank without increasing the number of parts by allowing the flage connection of the center vibe to come off due to impact force.

(Measures for Solving the Problem) A means according to the present invention for solving the above problem is to form the center vibe 3 of an automobile exhaust system with two pieces with opposing cut portions being slanted. , an inclined flange 14.15 is provided on both of the oblique cut portions in accordance with the inclination thereof, and two bolts are installed in the inclined direction of the inclined flange 14.15 and on both sides of the opening of the center vibe 3. Hole I6, +7
A slit is formed in one of the bolt holes 16.17 in the direction of the inclination of the slanted flange 14.15 and cuts out the outer edge of the flange! It is characterized by having 8.

(Function) Since the present invention is configured as described above, the impact force caused by a car accident is applied to both of the cut portions of the center vibe by the inclined flanges! 4.15 to connect the center vibe 3, the impact force in the axial direction of the center vibe 3 acts as a component force in the direction of the angle of inclination of the inclined flange 14.15.

This component force is applied to the inclined flanges 14, 1 which are fastened.
Acts as a force to shift 5. In addition, the inclined flange 14
．． 15, two bolt holes 16 and 17 are bored in the inclined direction and on both sides of the opening of the center vibe 3,
One of said bolt holes 16, 17 has said inclined flange 14.
Since the slit 18 is provided in the direction of inclination of 15 and cuts the outer edge of the inclination flange 14.15, the component force that acts as a force to displace the inclination flange 14.15 is applied to the bolt 22 fastened. acts as a shearing force, so when this shearing force becomes thicker than the frictional force on the surface of the inclined flange that is being fastened, a shift occurs in the fastening surface of the inclined flange 14 and 15, causing the flange to be fastened. bolt 22
is pushed by this shearing force and moves along with the shank of the inclined flange 14, +5, and comes out through the slit 18. As a result, the center vibe 3 becomes in a state where it is cut off from the flange portion.

(Example) An embodiment of the present invention will be described in detail below.

In FIG. 1, the cut portion of the center vibe 3 is formed obliquely to form a predetermined angle α, and flanges 14 and 15 are provided in line with this cut surface 19. This angle of inclination α is determined depending on the vehicle type, taking into account the impact force at the time of a collision, the support structure of the exhaust system, and the like. Further, in this embodiment, the flange 14.
15 is integrated with the center vibe 3, but flanges 14 and 15 separate from the center vibe 3 may be attached by welding.

The flange 15 is formed with a sealing surface 20 that protrudes from the tightening surface of the flange, and in addition to ensuring the sealing of this part, a gap of dimension C is formed between the flange eye and the mating surface of the bolt. The tightening force of 22 can be adjusted to adjust the frictional force between the flanges 14 and 15, so that the fastening surfaces of the flanges can be displaced in response to the set impact force. There is. As shown in FIGS. 2 and 3, two bolt holes 16.17 are formed in the flange 14.1s with the opening 19 of the center vibe 3 interposed therebetween. And these two bolt holes 16.17
is the opening +9 of the center vibrator 3 as shown in Fig. 1.
passing through the center of the flange 14.15 and on the axis of the flange 14.15 in the direction of inclination. These two bolt holes! A slit 18 is provided in one of the flange 6 and +7 so as to cut out the outer edge of the flange 14, 15 along the axis.

In this embodiment, this slit 18 is formed on one flange +
4 slit 18 is downward, the other flange! The flange +4.15 is attached to the center vibe 3 so that the slit 18 of 5 faces upward. In short, the slits 18.18 should be upside down from each other8.
Next, the mounting position of the flange 14.15 to the center vibe 3 is as shown in FIG. 5 and FIG.
The frame of the own vehicle 21 is bent due to the impact force when the vehicle 1 collides head-on, the weight of the engine, etc. (W), and the force F that pushes the center vibe 3 downward when it hits the center vibe 3 causes a large displacement force on the flange 14.15. Install it in a position where it occurs.

The operation of this embodiment configured as above will be explained next. First, in assembling the exhaust system, flanges 14 and 15 are fastened with bolts 22 in the same manner as before. When tightening with this bolt 22, due to the gap C, the bolt 2
The tightening force in step 2 is adjusted according to the vehicle type, and the preset impact force at the time of a car collision causes displacement of the fastening surfaces of the flanges 14 and 15.6 Next, as shown in Figure 4, When there is a head-on collision (arrow A), the engine (not shown) moves toward the rear of the vehicle, and at the same time, the center vibe 3 receives the impact force and is pushed toward the rear along with the engine. The axial impact force acting on the center vibe 3 at this time acts as a component force against the inclination angle α of the flange 14.15, and this component force acts in a direction that shifts the flanges 14.15 from each other. - As shown in Figure 6, the frame of the automobile 21 bends downward and hits the center vibe 3, causing a force F
The center vibrator 3 is pushed downward, and the resultant force of this force F and the above component force is the tightening force PJl' of the flange 14.15!
When the force becomes larger than the J force, a displacement occurs in the fastening surfaces of the flanges 14 and 15. Flange 14.15 like this
If a deviation occurs on the fastening surface of the flange, the force of this deviation will be applied to the flange +
4. A shearing force acts on the bolt 22 fastening Is, and the bolt 22 comes out of the slit 18, and the flanges 14 and 15 come off as shown in FIG. 4, and the center vibe 3 is cut off as shown in 3. become. By removing the flange 14.15 in this way, only the support for the rubber mount 11 is removed, the rubber mount 12.13 remains as it is, supporting the muffler 2.2, and the center vibe 3 hits the fuel tank 6. There is no such thing.

Next, the case of a rear-end collision will be explained. FIG. 7 is a diagram showing the back side of the automatic +l 121, in which the center vibe 3 is bent at a substantially right angle so as to be in contact with the fuel tank 6, and the muffler 2 is arranged so as to be located behind the fuel tank 6. In this example, in the event of a rear-end collision (arrow B) as shown in FIG.
Even if the fuel tank 6 moves forward due to the impact force of the collision due to rear deformation of the automobile 21, there is no strong impact force between the two, and the center vibe 3 is pushed while in contact with the fuel tank 6. The force of this pressing is the flange! This component force, which acts as a component force against the inclination angle α of 4.15, is applied to the flange 14.
．． When the tightening of 15 becomes larger than the frictional force, a shift occurs in the flange 14, 15, and this shift causes the flange 14, +
This acts as a shearing force on the bolt 22 fastening the bolt 5, and the bolt 22 comes out through the slit 18, and the flanges 14 and +5 come off. Flange 14.15 like this
By removing the center vibe 3 and fuel tank 6
The impact force between the two can be minimized, and damage to the fuel tank 6 can also be minimized.

(Effects of the Invention) As detailed above, according to the present invention, the center vibe is
The opposing cut portions are formed diagonally, and both of the diagonal cut portions are provided with slanted flanges that match the inclination to connect the center pipe, so that the impact force caused by the collision of the automatic type is applied to the inclination angle of the flanges. On the other hand, the component force acts in the direction of displacing the flange, and this component force can act as a shearing force on the bolts fastening the flange. Then, two bolt holes are made in the direction of inclination of the inclined flange and on both sides of the opening [ ] of the center pipe, and the outer edge of the flange is cut out in one of the bolt holes in the direction of inclination of the inclined flange. Since the slit is provided, the bolt is pushed through the slit by the shearing force along with the displacement of the flange, and the center pipe can be removed.

As a result, even if an automatic model collides head-on, the fuel tank will not be damaged due to deformation and movement of the center pipe, and
Even in the event of a rear-end collision, damage to the fuel tank caused by the center pipe can be minimized and no fires will occur.

In addition, the number of parts does not increase, and the assembly is no different from the conventional one, so the assembly is simple and I! It is also possible to provide an exhaust system that satisfies all aspects of safety in the event of a frontal collision or rear-end collision.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a front view of an example of a flange, FIG. 3 is a front view of an example of a flange, and FIG. 4 is a view of the embodiment of FIG. 1. A perspective view of the applied exhaust system, FIG. 5 is a schematic diagram of an automatic vehicle to which the embodiment of FIG. 1 is applied, FIG. 6 is a schematic diagram of the automatic vehicle in FIG. 1 is a schematic diagram showing the back side of the automatic mid-range to which the embodiment of FIG. 1 is applied, FIG. 8 is a schematic diagram showing the automatic mid-range of FIG. , Figure 1O is a perspective view of a conventional exhaust system using a flexible vibe, Figure 11 is a side view showing the main parts of a conventional exhaust system with a protective cover provided at the bottom of the fuel tank, and Figure 12 is a view of the fuel tank. FIG. 3 is a side view of a conventional exhaust device in which the entire surface of the exhaust device is inclined. 3... Center pipe 14... Inclined flange 15-... Inclined flange 18... Slit ■9... Center pipe cutting part name 1 = 3... Sen9-Vibe 14.15... Inclined flange 18... S1 Hat 19... Cutting surface of center pipe 2nd = 3rd ≦ 5th = ``η'' Figure 8 Figure 9 = Figure 10

Claims (1)

[Claims] (1) A center pipe of an automobile exhaust system is formed of two pipes with opposing cut portions being slanted, and a slanted flange is provided on both of the slanted cut portions in accordance with the inclination of the slanted flange. An automobile characterized in that two bolt holes are formed on both sides of the opening of the center pipe, and one of the bolt holes is provided with a slit in the direction of inclination of the slanted flange to cut out the outer edge of the flange. exhaust system.