JPS63167021A - Exhaust pipe device of engine - Google Patents

Abstract

PURPOSE:To permit flexure of an exhaust pipe by disposing an inward flange on the inner periphery of a snap ring fitted to the outer periphery of the exhaust pipe of a motorcycle or the like, and interposing a seal member between the inward flange and e flange member provided on the forward end portion of the exhaust pipe. CONSTITUTION:A snap ring 25 having an inward flange 25a projected on the inner periphery thereof is screwed on the end surface of an exhaust hole 23 of an engine 3 by a stud bolt 24, and the forward end portion 16a of an exhaust pipe 16 is flexibly clamped therebetween through the first and second seal members 26, 27. A flange member 16c is deposited on the end surface of the exhaust pipe 16, and the first and second seal members 26, 27 are brought into contact with the surface and back side of the flange member 16c. In this arrangement, when the exhaust pipe 16 tilts to the engine 3, though the flange member 16c presses the respective seal members 26, 27 on both sides and tilts, the seal members 26, 27 are always brought into contact with both surfaces of the flange member 16c by its elasticity so as to permit such tilting.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust pipe device suitable for, for example, an engine suspended on the body frame of a motorcycle.

Conventionally, the front end of the exhaust pipe of a motorcycle is fixed to the engine, the rear end forming the muffler is supported by the vehicle body frame, and the entire body is formed by welding or the like so that it cannot be separated. Therefore, when engine vibration or road vibration is transmitted to this type of exhaust pipe, a large stress is applied to the connection part of the exhaust pipe to the ennon. In order to resist this stress, if we tried to strengthen the connection part of the exhaust pipe to the engine by making it made of cast iron, as in the case of conventional e-vehicles, it would increase the weight unnecessarily and spoil the appearance. .

The present invention is aimed at eliminating such problems, and is characterized in that a sealing member having elasticity that can tolerate some degree of deflection is interposed at the end of the surface of the exhaust pipe connected to the engine.

Hereinafter, the present invention will be explained with reference to the illustrated embodiments.
In the figure, 1 is the body frame of a motorcycle, which is assembled by welding steel pipes and has a steering axis 'l? The main pipe 4 extends rearward from the engine 2 and supports the rear part of the engine 3, and the descending pipe 5 extends downward and supports the front of the engine 3. It has a so-called cradle shape connected to the Reference numeral 7 designates a seat villa that supports a passenger seat 8, and 9 designates a stay thereof, both of which are welded to the main pipe 4. A rear arm 11 is rotatably supported at the rear of the vehicle body frame 1, and has a rear wheel 12 at its rear end. A substantially triangular auxiliary frame 13 is fixed to the upper part of the rear arm 11, and the rear arm 11 is elastically supported at the top of the auxiliary frame 13 to the main pipe 4 portion of the vehicle body frame 1 via a buffer spring device 14. ing. 15 is a radiator, 16 is an exhaust pipe, 17 is an intake pipe, 18 is a carburetor, 19 is a fuel tank, and 20 is a drive chain for the rear wheels 12. The above configuration is not particularly different from a conventional motorcycle.

Furthermore, in this embodiment, the engine 3 is connected to the vehicle body frame 1,
It is floatingly suspended by bolts 21 and 22 via a rubber damper (not shown). The exhaust pipe 16 has a front m portion 16a made by bending a steel pipe, and a rear end portion 16b which is an expansion chamber and a muffling chamber formed by welding and assembling steel plates into a cylindrical shape. The exhaust pipe 16 and the engine 3 are flexibly and airtightly connected by a visible bent member shown in Figure $2. That is, a stud bolt 24 is attached to the end face of the exhaust hole 23 of the engine.
A retaining ring 25 having seven inward flange 25a recessed therein is screwed onto the inner periphery of the retaining ring 25.
The bent end of the exhaust gas '1716 is flexibly held between the seal members 26 and 27. 16C is a flange member welded to the end of the exhaust pipe 16, and this flange member IG
A first sealing member is interposed in contact with the front surface of c, and a second sealing member is interposed in contact with the back surface. The first and second sealing members 26 and 27 are made of a mixture of a lump of fine stainless steel wire and a soft heat-resistant material whose main material is asbestos, which is then bonded together and molded to give it elasticity. In addition, 28 is a stud.

The rear part 613 of the exhaust pipe 16 is supported by a flange 31 to a stay 29 protruding from the vehicle body frame 1. That is, a metal bushing 34 is inserted and supported through a rubber bushing 33 into a medium-high hole 29a provided at the roadside, and a bolt 36 passed through an elongated hole 35 provided in the flange 31 is inserted and supported by the bushing 34. 37 is a bag nut.

The exhaust pipe device configured in this manner operates as follows. When the exhaust pipe 16 is operated and vibrates, the front end 16a of the exhaust pipe 16 rotates around the flange 31 that is elastically supported by the rubber bush 33 at the rear end, or moves in the front-back direction.

At this time, when the exhaust pipe 16 tries to tilt with respect to the engine 3, at the joint between the exhaust pipe 16 and the exhaust pipe 16, the flange member 16c is connected to the first seal member 26 on one side and the second seal member 26 on the other side.
Although the seal member 27 is pressed and tilted, the first and second seal members 26 and 27 are always behind both sides of the flange member 16c due to their elasticity, so that the passage is kept airtight.

As described above, according to the present invention, in the device in which the end face of the exhaust hole of the engine and the surface of the flange member provided at the front GL1 portion of the exhaust pipe are connected via the first seal member having elasticity, An inward flange is provided protruding from the inner periphery of a retaining ring fitted on the outer periphery of the exhaust pipe, and the inward flange and the back surface of the flange member are overlapped with each other via a second seal member having elasticity. Since the retaining ring is tightened to the end of the exhaust hole, even if the ennon vibrates independently against the vehicle frame,
Since the front end portion of the exhaust pipe with the first and second elastic seal members interposed therebetween is bent, the free vibration of the engine is not hindered by the exhaust pipe.

On the other hand, since vibrations are absorbed by the elastic sealing member and do not cause large stress on the exhaust pipe itself, there is no need to strongly reinforce the front end of the W5A pipe, and the increase in weight is kept to a minimum. Even if there is a dimensional error between the pipe attachment parts, it can be tolerated.

Furthermore, since the first and second elastic seal members are interposed at the connection between the engine exhaust hole and the exhaust pipe, the configuration is simple, and the seal members and the exhaust pipe can be assembled to the engine at the same time. Therefore, effects such as easy assembly work can be obtained.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an example of the implementation of the present invention, so FIG. 1 is a partial side view of the motorcycle, FIG. shows the ■-■ cross section. DESCRIPTION OF SYMBOLS 1... Vehicle body frame, 3... Engine, 16... Exhaust pipe, 16c... Flange member, 25
...Retaining ring, 25a...Inward flange, 2G...First seal member, 27...Second seal member.

Claims (1)

[Claims] In a device that connects the end face of an engine exhaust hole and the front face of a flange member provided at the front end of the exhaust pipe via a first elastic seal member, the inner part of the retaining ring fitted on the outer periphery of the exhaust pipe is An inward flange is provided around the periphery, and a retaining ring is fastened to the end face of the exhaust hole so that the retaining ring overlaps with a second seal member having elasticity between the inward flange and the back surface of the flange member. Exhaust pipe equipment for engines.