An engine-driven working machine capable of favorably reducing exhaust sound (that is, noise) is provided. An engine-driven working machine 10 is a generator in which an engine 15 and a muffler 67 are housed in an inside 13 of an outer case 12. The generator 10 includes a tail pipe 68 that is provided at a lower portion 67a of the muffler 67, a discharge port 37 that is disposed above the tail pipe 68, and a baffle plate 84 that is disposed to face the discharge port 37. The discharge port 37 is formed in the outer case 12. Further, cooling air that is sent from a cooling fan 17 is guided to below the muffler 67 with the baffle plate 84.

An engine-driven working machine capable of favorably reducing exhaust sound (that is, noise) is provided. An engine-driven working machine 10 is a generator in which an engine 15 and a muffler 67 are housed in an inside 13 of an outer case 12. The generator 10 includes a tail pipe 68 that is provided at a lower portion 67a of the muffler 67, a discharge port 37 that is disposed above the tail pipe 68, and a baffle plate 84 that is disposed to face the discharge port 37. The discharge port 37 is formed in the outer case 12. Further, cooling air that is sent from a cooling fan 17 is guided to below the muffler 67 with the baffle plate 84.

A muffler cutter is fitted to a tailpipe of a vehicular exhaust system, the muffler cutter includes an exhaust pipe, a plurality of through-holes formed in a side wall of the exhaust pipe, a tubular heat shield plate provided around the exhaust pipe coaxially with the exhaust pipe, and a sound-absorbing heat insulator provided between the exhaust pipe and the tubular heat shield plate. The sound-absorbing heat insulator is partially provided between the exhaust pipe and the tubular heat shield plate so as to have a curved shape. A closed space having a curved shape is formed between the exhaust pipe and the tubular heat shield plate in an area in which the sound-absorbing heat insulator is not provided. The distance between the exhaust pipe and the tubular heat shield plate in an area in which the closed space is formed is 1 to 50 mm.

A muffler cutter is fitted to a tailpipe of a vehicular exhaust system, the muffler cutter includes an exhaust pipe, a plurality of through-holes formed in a side wall of the exhaust pipe, a tubular heat shield plate provided around the exhaust pipe coaxially with the exhaust pipe, and a sound-absorbing heat insulator provided between the exhaust pipe and the tubular heat shield plate. The sound-absorbing heat insulator is partially provided between the exhaust pipe and the tubular heat shield plate so as to have a curved shape. A closed space having a curved shape is formed between the exhaust pipe and the tubular heat shield plate in an area in which the sound-absorbing heat insulator is not provided. The distance between the exhaust pipe and the tubular heat shield plate in an area in which the closed space is formed is 1 to 50 mm.

The present invention provides a highly durable, electrically heated catalytic converter including an inner tube on which an insulation layer is formed, wherein the insulation layer is less susceptible to damage such as cracking and peeling even when thermal stress occurs in a curvature section of the inner tube where the insulation layer is formed. The present invention provides an electrically heated catalytic converter for purifying exhaust gas, the electrically heated catalytic converter including a catalyst carrier supporting a catalyst and configured to generate heat by energization; a case for accommodating the catalyst carrier; and an electrical insulation mat interposed between the catalyst carrier and the case, wherein the case includes an outer tube disposed at the outermost side and an inner tube disposed inside the outer tube; in a cross section upstream of the catalyst carrier taken along a plane including the central axis of the case, the inner tube includes one or more curvature sections curved so as to outwardly project and extended sections connected to the one or more curvature sections, an insulation layer including an amorphous inorganic material is formed at least on an inner surface of the one or more curvature sections and the extended sections of the inner tube, the one or more curvature sections include a first curvature section located closest to the catalyst carrier, the first curvature section has a first curvature section insulation layer formed thereon, the first curvature section insulation layer having a thickness of 100 to 400 μm, the extended sections include a first extended section connected to the first curvature section and adjacent to the catalyst carrier, the first extended section has a first extended section insulation layer formed thereon, and the thickness of the first curvature section insulation layer is greater than 1 time to less than 1.4 times the thickness of the first extended section insulation layer.

The present invention provides a highly durable, electrically heated catalytic converter including an inner tube on which an insulation layer is formed, wherein the insulation layer is less susceptible to damage such as cracking and peeling even when thermal stress occurs in a curvature section of the inner tube where the insulation layer is formed. The present invention provides an electrically heated catalytic converter for purifying exhaust gas, the electrically heated catalytic converter including a catalyst carrier supporting a catalyst and configured to generate heat by energization; a case for accommodating the catalyst carrier; and an electrical insulation mat interposed between the catalyst carrier and the case, wherein the case includes an outer tube disposed at the outermost side and an inner tube disposed inside the outer tube; in a cross section upstream of the catalyst carrier taken along a plane including the central axis of the case, the inner tube includes one or more curvature sections curved so as to outwardly project and extended sections connected to the one or more curvature sections, an insulation layer including an amorphous inorganic material is formed at least on an inner surface of the one or more curvature sections and the extended sections of the inner tube, the one or more curvature sections include a first curvature section located closest to the catalyst carrier, the first curvature section has a first curvature section insulation layer formed thereon, the first curvature section insulation layer having a thickness of 100 to 400 μm, the extended sections include a first extended section connected to the first curvature section and adjacent to the catalyst carrier, the first extended section has a first extended section insulation layer formed thereon, and the thickness of the first curvature section insulation layer is greater than 1 time to less than 1.4 times the thickness of the first extended section insulation layer.

Systems and methods are provided for a combined spark arrestor and muffler assembly. In one example, a system may include a combined housing, the combined housing including a spark arrestor portion including a plurality of stator fins, and a muffler portion including acoustic packing, the muffler portion fluidically coupled to the spark arrestor portion via a first sliding joint and a second sliding joint. In this way, a single component of a vehicle exhaust system may reduce sparks and/or carbon deposits in exhaust gas, while also reducing exhaust noise.

An exhaust tail trim for a vehicle capable of being manufactured in various colors and having advantages of improving aesthetic sense, improving sense of integrated design and improving merchantability of a vehicle may include a heat pipe assembly disposed at an outside of an exhaust pipe through which exhaust gas is discharged; and a trim cover disposed at an end portion of the exhaust pipe and located at an outside of the heat pipe assembly, where the trim cover is made of synthetic resin.

An apparatus for shielding hot regions, in particular of an internal combustion engine, includes a heat shield with a through hole. The apparatus has a component, in particular a heat source, with a fastening region which has a receptacle and a shoulder which surrounds the receptacle at least partially. The shoulder extends through the through hole of the heat shield. The apparatus has a fastening element, in particular a screw, which fastens the heat shield to the fastening region, the fastening element being supported on the shoulder, extending through the through hole of the heat shield, and being fastened in the receptacle.

An apparatus for shielding hot regions, in particular of an internal combustion engine, includes a heat shield with a through hole. The apparatus has a component, in particular a heat source, with a fastening region which has a receptacle and a shoulder which surrounds the receptacle at least partially. The shoulder extends through the through hole of the heat shield. The apparatus has a fastening element, in particular a screw, which fastens the heat shield to the fastening region, the fastening element being supported on the shoulder, extending through the through hole of the heat shield, and being fastened in the receptacle.