초록 ▼

In the exhaust fluid path, there are provided a porous pipe that is in communication with a muffling chamber via a plurality of small through-holes formed across a wall thickness of the pipe, and an inner pipe of a given length is inserted in the porous pipe with a gap formed between the outer surfa

In the exhaust fluid path, there are provided a porous pipe that is in communication with a muffling chamber via a plurality of small through-holes formed across a wall thickness of the pipe, and an inner pipe of a given length is inserted in the porous pipe with a gap formed between the outer surface of the inner pipe and the inner surface of the porous pipe. The gap is narrowed or closed in its outlet portion and thus the exhaust sound waves flowing through the gap are compressed so that interference and scattering into the muffling chamber of the exhaust sound waves via the small through-holes are promoted, thereby enhancing muffling performance. A plurality of small through-holes may also be formed in the inner pipe. A relatively large opening may be formed in part of the porous pipe to open into the muffling chamber, or a relatively large space may be formed which divides the porous pipe into two pipe elements and opens into the muffling chamber. The porous pipe may be formed as a dual-pipe structure to provide a triple-pipe structure as a whole. Another alternative arrangement may be such that the muffling chamber is partitioned by a wall having a plurality of small through-holes so as to provide a sub-chamber and that the tubular exhaust path opens into the sub-chamber so as to enhance exhaust efficiency.

대표청구항 ▼

A muffler for an internal combustion engine comprising: a muffler body including an entry port for introducing exhaust fluid into said muffler body, at least one chamber provided in said muffler body, and an exit port for discharging the exhaust fluid out of said muffler body, said entry and exit po

A muffler for an internal combustion engine comprising: a muffler body including an entry port for introducing exhaust fluid into said muffler body, at least one chamber provided in said muffler body, and an exit port for discharging the exhaust fluid out of said muffler body, said entry and exit ports being disposed in linear alignment with each other; a first pipe section extending continuously between said entry and exit ports within said muffler body so as to allow the exhaust fluid to pass through said first pipe section in a predetermined exhaust flow direction from said entry port to said exit port, said first pipe section including a porous portion having a plurality of small through-holes formed across a wall thickness thereof in such a manner that said porous portion of said first pipe section communicates with said chamber via said small through-holes; and a second pipe section including a pipe of a given length that is inserted in said porous portion of said first pipe section and forming a gap between an outer peripheral surface of said pipe and an inner peripheral surface of said porous portion of said first pipe section, said gap having upstream and downstream end portions as defined by said exhaust flow direction, said upstream end portion of said gap being in communication with an inner space of said porous portion of said first pipe section.