JPH09228833A - Exhaust pipe support structure for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure, and to diminish vibration by providing the structure with a retaining means retaining the rotation of a clamp with respect to an exhaust pipe, and with a suspension means combining the clamp with an insulator, and thereby letting the exhaust support structure be commonly used as the clamp combining two exhaust pipes with each other. SOLUTION: The exhaust pipe of an engine is divided into a front pipe 1 and a tail pipe 2 so as to be formed, and an anulus ring shaped clamp 3 is provided in order to connect both the pipes 1 and 2 with each other. The aforesaid clamp is formed in a C shape, and respective abutment parts faced to each other while a cut-out is being held, are fastened with a bolt 7. As a retaining means preventing the clamp 3 from being rotated, a projection 13 is projected in a crest shape out of a flange part 12, Meanwhile, a recessed part 33 is formed in the clamp 3, which is so caved as to be engaged with the projection 13, and the pipe is suspended so as to be supported by inserting an arm part 34 projected out of the clamp 3 into the slit of rubber made insulator 8 suspending the connecting part of the pipes 1 and 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine exhaust pipe support structure.

[0002]

2. Description of the Related Art In an automobile engine or the like, an exhaust pipe is arranged under the floor of a vehicle body and is divided into a plurality of exhaust pipes. The exhaust pipes are connected to each other through a pipe joint such as a clamp to ensure maintainability.

The exhaust pipe is suspended and supported by the vehicle body through a plurality of rubber insulators so that vibrations of the exhaust pipe are not transmitted to the vehicle body.

A bracket or the like for connecting the insulator is provided in the middle of the exhaust pipe.

[0005]

However, in such a conventional engine exhaust pipe supporting structure, a bracket that suspends the exhaust pipe in the middle thereof increases the number of parts provided in the exhaust system and increases the weight. There is a problem that it causes increase and deterioration of productivity.

Further, the connecting portion of each exhaust pipe connected through the clamp is provided at the position of the node having the smallest amplitude when the exhaust pipe is regarded as a vibration system. However, since a bracket that connects the insulator in the middle of the exhaust pipe must be provided so as to avoid the clamp, it is not possible to support the portion of the exhaust pipe with the smallest amplitude, and the vibration of the exhaust pipe propagates to the vehicle body. The problem is that it is easy.

The present invention has been made in view of the above problems, and it is an object of the present invention to achieve both simplification of the structure and reduction of vibration in an engine exhaust pipe support structure.

[0008]

According to a first aspect of the present invention, there is provided an exhaust pipe supporting structure for an engine, wherein an exhaust passage for guiding exhaust gas from the engine, a plurality of exhaust pipes constituting the exhaust passage, and the exhaust pipes are mutually connected. In an exhaust pipe support structure of an engine including an annular clamp to be connected and an insulator made of an elastic material for suspending the exhaust pipe, a detent means for preventing rotation of the clamp with respect to the exhaust pipe and a suspension for connecting the clamp to the insulator. And lowering means.

According to a second aspect of the present invention, there is provided the exhaust pipe support structure for an engine according to the first aspect of the present invention, wherein the rotation preventing means forms a protrusion on the exhaust pipe and engages the protrusion with a clamp. Form a recess or hole.

According to a third aspect of the present invention, in the exhaust pipe supporting structure for an engine according to the first or second aspect of the present invention, as the suspending means, an arm portion protruding from a clamp in a radial direction of the clamp is formed. A slit is formed in the insulator for inserting the arm portion, and a tip of the arm portion protruding from the slit is bent to form a stopper portion.

[0011]

In the exhaust pipe support structure of the engine according to the first aspect, the exhaust pipe is elastically supported by the insulator via the clamp. Vibration of the exhaust pipe is absorbed by elastic deformation of the insulator.

By preventing the clamp from rotating with respect to the exhaust pipe through the rotation preventing means, the insulator is prevented from being twisted or twisted, and the insulator can maintain a desired vibration damping effect.

By suspending and supporting the exhaust pipe via the clamp, it is possible to reduce the number of parts such as brackets provided for suspending the exhaust pipe midway.
The number of parts provided in the exhaust system can be reduced to reduce weight and improve productivity.

Since the connection portion of each exhaust pipe is provided at the position of the node having the smallest amplitude when the exhaust pipe is regarded as the vibration system, the connection portion of each exhaust pipe is elastically supported by the insulator via the clamp. By doing so, the vibration of the exhaust pipe can be suppressed from propagating to the vehicle body or the like.

In the exhaust pipe support structure for an engine according to a second aspect of the present invention, in the clamp, the recess or hole provided in the clamp engages with the projection of the exhaust pipe to thereby seal the connection portion of each exhaust pipe. The rotation with respect to the exhaust pipe is prevented without being damaged.

In the exhaust pipe support structure for an engine according to a third aspect of the present invention, the clamp is coupled to the insulator by inserting an arm portion projecting in the radial direction of the clamp into a slit opened in the insulator.

Since the arm portion is formed with a stopper portion whose tip is bent, the arm portion is prevented from coming off the slit.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 2, the engine exhaust pipe is
It is divided into a front pipe 1 and a tail pipe 2. The upstream end of the front pipe 1 communicates with each cylinder of the engine via an exhaust manifold (not shown). Exhaust gas from each cylinder is collected by an exhaust manifold, and is discharged to the outside through a catalytic converter 5 and an exhaust muffler (silencer) 4.

The front pipe 1 has an inlet portion 11 that fits inside the tail pipe 2 and a flange portion 12 that is connected to the base end side of the inlet portion 11 and bulges in an annular shape.

The tail pipe 2 has a flange portion 22 that expands like a trumpet at the pipe end. The flange portion 22 of the tail pipe 2 is joined to the flange portion 12 of the front pipe 1 via the gasket 6.

An annular clamp 3 is provided as a pipe joint for connecting the front pipe 1 and the tail pipe 2 to each other.

The annular clamp 3 is formed in a C-shape with a notch in the middle, and the abutting end portions facing each other across the notch are fastened via bolts 7. The cross section of the clamp 3 is curved in an arc shape so as to surround the flange portions 12 and 22.

The clamp 3 surrounds the flanges 12 and 22, and the joint ends thereof are fastened together via bolts 7 to connect the front pipe 1 and the tail pipe 2 to each other. Gasket 6 is each flange 1
It is interposed between 2 and 22 and seals between both.

As a rotation preventing means for preventing the rotation of the clamp 3 with respect to the front pipe 1 and the tail pipe 2, a protrusion 13 is projected on the flange portion 12 in a mountain shape, while a depression is formed on the clamp 3 so as to engage with the protrusion 13. Recess 3
3 is formed. The clamp 3 is prevented from rotating with respect to the front pipe 1 by engaging the recess 33 of the clamp 3 with the protrusion 13 of the flange 12.

An engine (not shown) is mounted on the front part of the vehicle, and the front pipe 1 and the tail pipe 2 are arranged under the floor of the vehicle. The front pipe 1 and the tail pipe 2 are suspended and supported on the vehicle body via a plurality of rubber insulators.

An insulator 8 is provided to suspend the connecting portion between the front pipe 1 and the tail pipe 2. This insulator 8 has a hole 41 opened at the upper part thereof and is fastened to a member of the vehicle body through a bolt 9 which is inserted through the hole 41.

As a suspending means for connecting the clamp 3 to the insulator 8, an arm portion 34 is formed on the clamp 3 so as to project in the radial direction, and a slit 42 for inserting the arm portion 34 is opened in the lower portion of the insulator 8.

A stopper portion 35 is bent in an L shape at the tip of the arm portion 34 of the clamp 3 so that the arm portion 34 does not come out of the slit 42 of the insulator 8.

The operation will be described below.

The front pipe 1 and the tail pipe 2 are elastically supported by the insulator 8 via the clamp 3 with respect to the vehicle body. Vibration of the front pipe 1 and the tail pipe 2 is absorbed by elastic deformation of the insulator 8.

The annular clamp 3 has flanges 12 and 2
When the two ends are fastened together via bolts 7 in the state of surrounding 2, the recess 53 engages with the projection 13 of the flange 12 and rotation with respect to the front pipe 1 is prevented.

Since the rotation of the clamp 3 with respect to the front pipe 1 is prevented in this way, the insulator 8 is provided via the arm portion 34 protruding from the clamp 3 in the radial direction.
It is possible to prevent twisting and twisting of the insulator, and the insulator 8 can maintain desired vibration damping characteristics.

By suspending and supporting the front pipe 1 and the tail pipe 2 on the vehicle body through the clamp 3, the number of parts such as brackets provided for suspending the front pipe 1 and the tail pipe 2 in the middle can be reduced. Therefore, the weight of the exhaust system can be reduced and the productivity can be improved.

Since the connecting portion between the front pipe 1 and the tail pipe 2 is provided at the position of the node having the smallest amplitude when the exhaust pipe is regarded as the vibration system, the connecting portion between the front pipe 1 and the tail pipe 2 is connected via the clamp 3. The elastic support by the insulator 8 effectively suppresses the vibration of the exhaust pipe from propagating to the vehicle body.

As a rotation preventing means for preventing the rotation of the clamp 3, the protrusions 13 are projected on the flange 12 in a mountain shape, while the recesses 33 are formed in the clamp 3 so as to engage with the protrusions 13. Exhaust gas can be prevented from leaking without impairing the sealing property between the front pipe 1 and the tail pipe 2.

In the present embodiment, the clamp 3
On the other hand, although the configuration is shown in which the concave portion 33 that engages with the protrusion 13 of the flange portion 12 is shown, as shown in FIG.

[0038]

As described above, in the exhaust pipe supporting structure for an engine according to claim 1, the bracket provided for suspending and supporting the exhaust pipe through the clamp so as to suspend the middle of the exhaust pipe. It is possible to reduce the number of parts, etc., and reduce the number of parts provided in the exhaust system to reduce the weight and improve the productivity. Further, since the connecting portion of each exhaust pipe is provided at the position of the node having the smallest amplitude when the exhaust pipe is viewed as a vibration system, the vibration of the exhaust pipe can be suppressed from propagating to the vehicle body or the like.

In the exhaust pipe support structure for an engine according to a second aspect of the present invention, the clamp has a recessed portion or a hole provided in the clamp that engages with a projection of the exhaust pipe to thereby seal the exhaust pipe. The rotation with respect to the exhaust pipe is prevented without being damaged.

In the exhaust pipe support structure for an engine according to a third aspect of the present invention, in the clamp, the arm portion projecting in the radial direction of the clamp is connected to the insulator by being inserted into the slit opened in the insulator, and the tip thereof is bent. The stopper portion prevents it from coming off the slit.

[Brief description of drawings]

FIG. 1 is a perspective view showing a joint portion of an exhaust pipe in an embodiment of the present invention.

FIG. 2 is a perspective view of an exhaust system of the same.

FIG. 3 is a perspective view showing a joint portion of an exhaust pipe in another embodiment.

[Explanation of symbols]

 1 Front pipe 2 Tail pipe 3 Clamp 6 Gasket 8 Insulator 12 Flange part 13 Protrusion 22 Flange part 33 Recess 34 Arm part 35 Stopper part 42 Slit 53 Hole part

Claims (3)

[Claims] 1. An exhaust passage for guiding exhaust gas from an engine, a plurality of exhaust pipes constituting the exhaust passage, an annular clamp for connecting the exhaust pipes to each other, and an insulator made of an elastic material for suspending the exhaust pipe. An exhaust pipe support structure for an engine, comprising: an anti-rotation device for preventing the clamp from rotating with respect to the exhaust pipe; and a suspending device for connecting the clamp to the insulator. . 2. The engine exhaust according to claim 1, wherein the rotation preventing means includes a projection formed on the exhaust pipe and a recess or hole engaging with the projection with respect to the clamp. Tube support structure. 3. As the suspending means, an arm portion projecting in a radial direction of the clamp is formed with respect to the clamp, a slit for inserting the arm portion into the insulator is opened, and a tip projecting from the slit of the arm portion is formed. The exhaust pipe support structure for an engine according to claim 1 or 2, wherein the stopper portion is formed by bending.