An exhaust muffler is made up of a plurality of layers including an exhaust passage pipe and expansion chambers, and includes a front assembly and a rear assembly sub-assembled separately from the front assembly. The front assembly includes a front exhaust passage pipe, a front muffler body disposed in covering relation to the outside of the front exhaust passage pipe and cooperating with the front exhaust passage pipe in making up double-walled pipes, and an exhaust valve disposed in the front exhaust passage pipe. The rear assembly includes a rear exhaust passage pipe and a rear muffler body disposed in covering relation to the outside of the rear exhaust passage pipe and cooperating with the rear exhaust passage pipe in making up double-walled pipes. There is thus provided an exhaust device for an internal combustion engine in which the accuracy of a position where the exhaust valve is installed is high.

Disclosed is an exhaust-gas after-treatment device for an internal combustion engine, in particular for a ship's diesel internal combustion engine that is operated with heavy oil, including: a housing through which exhaust gas flows; exhaust-gas purification chambers formed in the housing, which chambers hold catalysts and/or particulate filters in order to purify the exhaust gas; and muffler chambers formed in the housing, which chambers have a defined depth for muffling sound in the flow direction. The exhaust-gas purification chambers and the muffler chambers are arranged spatially in series and parallel to one another on the flow side.

A silencer insert (10) for a silencer of an exhaust system includes a first and a second partition wall (11, 12) and a connecting wall (13) arranged therebetween. The first partition wall (11) defines a first plane (E1), the second partition wall (12) defines a second plane (E2), and the connecting wall (13) defines a third plane (E3). At least one of the first partition wall, the second partition wall, and the connecting wall includes at least one perforated area (15). The connecting wall (13) is formed in one piece with the first partition wall (11) and the second partition wall (12). The first plane encloses with the second plane an angle of not more than 60°, the first plane and the second plane being particularly in parallel. A silencer is provided including a housing (1) receiving the silencer insert (10). A method is provided for manufacturing the silencer insert.

An exhaust muffler for transverse installation in a vehicle includes a muffler housing (26) elongated in the direction of a housing longitudinal axis (G) with a housing jacket (28) and two front walls (30, 32). The two front walls (30, 32) are arranged at spaced locations from one another and define an interior (34) of the muffler with the housing jacket (28). At least one inlet pipe (36) leads into the interior (34) of the muffler and at least one outlet pipe (20) leads out of the interior (34) of the muffler. At least one front wall (30, 32) has at least one predetermined deformation area (50, 52).

A combined exhaust gas noise silencer consisting of a system of hollow elements with a mutual housing comprising a front face of the silencer connected to the supply pipe of exhaust gases, and a rear face of the silencer with an outlet from the rear face of the silencer, where the original—inlet exhaust gas (İ.sub.p) carrying a noise wave is divided into at least two flows—an exhaust gas flow (İ.sub.z) carrying a shifted noise wave with delayed wave length, and an exhaust gas flow (İ.sub.n) carrying a non-shifted noise wave, which are subsequently combined into a common exhaust gas flow (İ.sub.s).

An exhaust muffler includes first and second pipes which extend through a casing, and which are disposed so that a downstream end of the first pipe faces an upstream end of the second pipe, wherein the downstream end of the first pipe and the upstream end of the second pipe are disposed so as to be spaced from each other in an axial direction, one end part of a support member having a circular cross section that has a smaller diameter than those of the first and the second pipes is fixed to one of a first lid member covering an opening at the downstream end of the first pipe and a second lid member covering an opening at the upstream end of the second pipe, and the other end part of the support member is slidably fitted to the other of the first and the second lid members.

A muffler for a vehicle includes a first expansion chamber in which an exhaust gas flowing in from an inlet pipe is expanded, and a bracket that is placed on an inner surface of the first expansion chamber to oppose a blow-off port of the inlet pipe and that has a mountain shape protruding toward a side of the inlet pipe. The bracket includes a top surface which opposes the blow-off port of the inlet pipe, and inclined surfaces which incline from the top surface toward corners of the first expansion chamber.

An engine muffler apparatus for reducing noise and pollution from small gas engines such as those on landscaping tools includes an outer housing having a central neck extension with a principal aperture extending through to an outer housing cavity. The neck extension is selectively engageable with an exhaust of a small gas engine. The outer housing cavity has a plurality of vent apertures. An intake extension tube and a medial tube are coupled to the outer housing cavity. The medial tube has a medial cavity. A first filtering medium is coupled within the medial cavity and filters pollutants passing therethrough. A second filtering medium is coupled within the outer housing cavity outside of the medial tube and dampens sound waves passing through the apparatus from the exhaust.

One aspect of the present disclosure provides an exhaust unit including a housing, a wall member, a catalyst, and a muffler chamber. The housing includes a feed inlet and a discharge outlet. The housing is configured such that an exhaust gas of an internal combustion engine is introduced from the feed inlet, and the exhaust gas is discharged from the discharge outlet. The wall member is disposed in the housing, and forms a cylindrical flow path that guides a flow of the exhaust gas introduced from the feed inlet to curve along an outer circumference of an interior of the housing. The catalyst is disposed in the flow path. The muffler chamber communicates with the flow path in a downstream side of the catalyst in the flow path. The wall member serves as a part of a wall that defines an inside and an outside of the muffler chamber.

A substantially metal-free exhaust subsystem includes an exterior housing formed of polymer; and a pipe formed of a layered fibers formed at least partially of glass, and bound by an inorganic binder. The fibers may be glass or ceramic, and may define micro-pores on the interior of the pipe that aid in absorbing acoustic energy, and thereby attenuating exhaust noise.