Exhaust system structure in internal combustion engine for vehicle

Patent metadata

Field	Value
Publication number	US-9512771-B2
Application number	US-201514845517-A
Country	US
Kind code	B2
Filing date	Sep 4, 2015
Priority date	Sep 30, 2014
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A catalytic device connected to an exhaust muffler from the front of the exhaust muffler to form substantially the shape of a T as viewed in plan is provided between an exhaust pipe and the exhaust muffler. One end portion of a reinforcing cover covering the catalytic device is fixed to an upstream end portion of the catalytic device, and another end portion of the reinforcing cover is fixed to the exhaust muffler. An extending portion extending rearwardly upward along the outer periphery of the exhaust muffler is formed integrally with the rear portion of a first heat insulating member covering the reinforcing cover from above. A second heat insulating member integrally having a cover portion covering the extending portion from above and inclined rearwardly upward is disposed so as to cover the exhaust muffler from above.

First claim

What is claimed is:

1. An exhaust system structure in an internal combustion engine for a vehicle in which an engine main body having a cylinder head is mounted on a vehicle body frame, and an exhaust muffler to which exhaust gas from the cylinder head is guided extends in a vehicle width direction and is disposed on a rear portion of the vehicle body frame, the exhaust system structure comprising:
an exhaust pipe extending in a forward-rearward direction in front of the exhaust muffler so as to guide the exhaust gas from the cylinder head;
a catalytic device disposed between the exhaust pipe and the exhaust muffler, the catalytic device being coaxially connected to the exhaust pipe and connected to the exhaust muffler from a front of the exhaust muffler so as to form substantially a shape of a T as viewed in plan;
a reinforcing cover covering the catalytic device, the reinforcing cover having one end portion fixed to an upstream end portion of the catalytic device and having another end portion fixed to the exhaust muffler, and the reinforcing cover being formed so as to increase in at least width along the vehicle width direction with decreasing distance to the exhaust muffler;
a first heat insulating member covering the reinforcing cover from above, an extending portion extending rearwardly upward along an outer periphery of the exhaust muffler, the extending portion being formed integrally with a rear portion of the first heat insulating member; and
a second heat insulating member disposed so as to cover the exhaust muffler from above, the second heat insulating member integrally having a cover portion covering the extending portion from above and inclined rearwardly upward.

2. The exhaust system structure in an internal combustion engine for a vehicle according to claim 1 ,
wherein a gap that allows circulation of air is formed between the extending portion and the cover portion.

3. The exhaust system structure in an internal combustion engine for a vehicle according to claim 2 ,
wherein a front end supporting portion formed in a semicircular shape so as to abut against an upper outer periphery of the exhaust pipe is formed in a front end portion of the first heat insulating member, a band for radial positioning of the front end supporting portion with respect to the exhaust pipe is wrapped around an outer periphery of the front end supporting portion and a lower outer periphery of the exhaust pipe, and the rear portion of the first heat insulating member is fixed by bolts to both of a left side and a right side of the reinforcing cover.

4. The exhaust system structure in an internal combustion engine for a vehicle according to claim 3 ,
wherein the catalytic device includes a housing cylinder connected to the exhaust pipe and a metal catalyst housed within the housing cylinder, a muffler case of the exhaust muffler is provided with an exhaust gas introduction hole communicating with an inside of the muffler case and provided with a supporting cylindrical portion extending frontward coaxially with the exhaust gas introduction hole, and a rear end portion of the housing cylinder is supported by the supporting cylindrical portion.

5. The exhaust system structure in an internal combustion engine for a vehicle according to claim 4 ,
wherein the rear end portion of the housing cylinder is press-fitted into the supporting cylindrical portion, and a front end of the supporting cylindrical portion is disposed forward of a rear end of the metal catalyst within the housing cylinder.

Assignees

• Honda Motor Co Ltd

Inventors

• Mahira Hiroshi
• Akagi Takashi
• Hotozuka Makoto

Classifications

• B60K13/04

  concerning exhaust · CPC title

• B60Y2200/86

  Carts; Golf carts · CPC title

• F01N3/2803

  characterised by structure, by material or by manufacturing of catalyst support · CPC title

• F01N2230/04

  Catalytic converters · CPC title

• F01N13/14 Primary

  having thermal insulation {(exhaust manifolds F01N13/102)} · CPC title