US 7,451,785 B2 · Flexible tube

Abstract

A flexible tube 10 of the present invention is disposed downstream of a exhaust path from an engine E, and formed of an outer bellows 3 as an outer tube and an inner bellows 4 as an inner tube; pleats 4c,4c of the inner bellows 4 are smaller in depth and pitch than the pleats 3c of the outer bellows 3, and the buffering space S is provided with a gap t between the pleats bottoms of the outer bellows 3 and the pleats tops of the inner bellows 4, and further, a partition 17 that splits the exhaust path is disposed in the inner bellows 4. For this reason, sound insulation effect is improved, and the lowering of the temperature of the exhaust gas is suppressed, leading to quick temperature rise of the exhaust gas to be fed into the catalytic converter, thereby promoting the activation of the catalysts and improving the capability to purify exhaust gas, and the exhaust efficiency can be improved thereby increasing output performance of the engine.

Claims25

Dependent claims

A flexible tube to be disposed on an exhaust path for exhaust gas from an engine, the tube comprising:

an outer bellows that is an outer tube having a flexible part with bellows,
an inner bellows that is an inner rube having a flexible part, a gap as a buffering space being provided between the outer bellows and the inner bellows, the inner bellows being fixed to an exhaust gas inlet of the outer bellows and extending toward an exhaust gas outlet thereof,
an auxiliary pipe, an overlapping space being provided where the inner bellows and the auxiliary pipe overlap each other, the auxiliary pipe being fixed to the exhaust gas outlet of the outer bellows and extending toward the exhaust gas inlet;
and
an interference prevention member held in the overlapping space.

2 more elements

A flexible tube to be disposed on an exhaust path for exhaust gas from an engine, the tube comprising an outer bellows that is an outer tube having a flexible part with bellows, an inner bellows that is an inner tube having a flexible part, the inner tube being fixed to one open end part of the outer bellows, in which a gap as a buffering space is provided between the outer bellows and the inner bellows;

and an interference prevention member,
wherein an overlapping space is provided where the outer bellows and the inner bellows overlap each other, the outer bellows being fixed to an outlet of the exhaust gas from the engine and the inner bellows extending toward an exhaust gas outlet;
and the interference prevention member is held in the overlapping space.

Dependencies are inferred from the claim text.

Flexible tube

Life of this patent

Flexible tube

Life of this patent

Abstract

Claims25