Futaba Industrial Co., Ltd.

Shinnosuke Toichi

Katsuhiko Kainuma

Hayato Tawada

Seiji Kondo

Munehiro Tsubosaka

Masahiro Jinda

Takehiro Miura

Toshikazu Namikiri

Yoshiaki Kataoka

Takuya Kondo

Takeshi Osanai

Manabu Yokoyama

Tsuneyuki Higashino

Yuta Shimizu

Provided is a muffler that can reduce sound pressure of a standing wave in an outlet pipe and, at the same time, can inhibit generation of flow noise. In one aspect of the present disclosure, the muffler includes a housing, an outlet pipe, a cover that covers the outlet pipe. The outlet pipe includes an outlet end and at least one communication hole. The outlet end opens into the housing. The at least one communication hole is formed in an outer circumferential surface of the outlet pipe. The cover includes a wall portion and an opening. The wall portion is disposed to overlap with the at least one communication hole in a radial direction of the outlet pipe. The opening communicates the at least one communication hole and an internal space of the housing with each other.

Muffler

An exhaust pipe with a double pipe structure that can reduce generation of a turbulent flow of exhaust gases is provided. In one aspect of the present disclosure, the exhaust pipe includes a double pipe and a retention member. The double pipe includes an inner pipe and an outer pipe. The retention member is disposed in a gap provided between an outer circumferential surface of the inner pipe and an inner circumferential surface of the outer pipe. The retention member is disposed at at least one end of the double pipe. At the end of the double pipe where the retention member is disposed, a radial clearance between the outer circumferential surface of the inner pipe and the inner circumferential surface of the outer pipe at an opening of the inner pipe is smaller than the radial clearance in an arrangement area where the retention member is disposed.

Exhaust pipe

A muffler including a double-pipe structure to muffle sounds in two or more frequencies is provided. The muffler includes an inner and outer pipes with a clearance therebetween. The inner pipe includes a first and second outer surfaces, and, at one end, an opening communicating with the outer pipe. The clearance communicates with an exhaust passage via the opening. The second outer surface forms the opening and is situated closer to the center of the inner pipe than the first outer surface is. A space between the inner and outer pipes is closed due to a contact between the first outer surface and an inner-circumferential surface of the outer pipe. A part of the clearance is formed between the first outer surface and the inner-circumferential surface. The outer-circumferential surfaces of the inner pipe include at least one communication hole that communicates the inner pipe with the clearance.

A muffler includes an inner pipe and an outer pipe which, along with the inner pipe, forms a double-wall pipe. A cavity is provided between the inner and outer pipes. A first end of the double-wall pipe is closed between the inner and outer pipes, and a second end of the double-wall pipe has an opening between the inner and outer pipes. The cavity communicates with an exhaust channel via the opening. The cavity is formed as a result of the inner pipe being shaped in a manner such that a portion of an outer-circumferential surface of the inner pipe is positioned on an inner-circumferential side relative to a reference, the reference being a position of an outer-circumferential surface of the outer pipe.

A heat insulating structure for an exhaust junction pipe to be disposed in an area in which exhaust gas passages having different respective lengths are merged together comprises a first heat insulation portion that covers and provides heat insulation for at least a portion of one branch part of branch parts that are branched in the exhaust junction pipe; the one branch part forms one exhaust gas passage in a not-yet-merged state of the exhaust gas passages, and forms the one exhaust gas passage having a short length.

Growing community of inventors

Okazaki, Japan

Shinnosuke Toichi