Abstract: An intake manifold includes a surge tank, an inlet pipe, and intake pipes. The surge tank includes a curved portion and a bulging portion. The curved portion forms a curved outer wall of the surge tank and includes an inner surface that is continuous with inner surfaces of entrances of the intake pipes. The bulging portion bulges into the surge tank toward the curved portion and overlaps with an imaginary extension of an exit of the inlet pipe into the surge tank. The bulging portion includes a flow changing portion. The flow changing portion is configured to direct a flow of intake air toward a section that is more interior into the surge tank than the bulging portion in relation to the inlet pipe and located on part of the inner surface of the surge tank that is continuous with the inner surface of the curved portion.

Abstract: An intake manifold includes a surge tank, an inlet pipe, and intake pipes. The surge tank includes a curved portion and a bulging portion. The curved portion forms a curved outer wall of the surge tank and includes an inner surface that is continuous with inner surfaces of entrances of the intake pipes. The bulging portion bulges into the surge tank toward the curved portion and overlaps with an imaginary extension of an exit of the inlet pipe into the surge tank. The bulging portion includes a flow changing portion. The flow changing portion is configured to direct a flow of intake air toward a section that is more interior into the surge tank than the bulging portion in relation to the inlet pipe and located on part of the inner surface of the surge tank that is continuous with the inner surface of the curved portion.

Abstract: An intake duct includes a duct body. The duct body includes an upstream opening and a downstream opening. The duct body includes a twisted and bent portion. The twisted and bent portion includes a first side section and a second side section. The upstream opening and the downstream opening respectively include first sections, which are on a first side in the height direction. The upstream opening and the downstream opening respectively include second sections, which are on a second side in the height direction. The twisted and bent portion is twisted and bent such that the first side section connects the first section of the upstream opening and the second section of the downstream opening to each other, and the second side section connects the second section of the upstream opening and the first section of the downstream opening to each other.

Abstract: The intake manifold includes an intake air introduction port, a surge tank and a plurality of intake pipes. The intake air introduction port is connected to one end side of the surge tank in a direction in which the intake pipes are arranged. The surge tank is provided with a stepped portion over the direction in which the intake pipes are arranged. The stepped portion has an erected wall erected from a surface of the surge tank and connected to the plurality of intake pipes, and a curved wall connecting a tip side of the erected wall and the surface of the surge tank. Further, the surge tank is provided with a concave portion recessed toward the stepped portion at an intermediate portion in the direction in which the intake pipes are arranged.

Abstract: The intake manifold includes an intake air introduction port, a surge tank and a plurality of intake pipes. The intake air introduction port is connected to one end side of the surge tank in a direction in which the intake pipes are arranged. The surge tank is provided with a stepped portion over the direction in which the intake pipes are arranged. The stepped portion has an erected wall erected from a surface of the surge tank and connected to the plurality of intake pipes, and a curved wall connecting a tip side of the erected wall and the surface of the surge tank. Further, the surge tank is provided with a concave portion recessed toward the stepped portion at an intermediate portion in the direction in which the intake pipes are arranged.

Abstract: An air cleaner includes a housing and a tubular air cleaning element, which is accommodated in the housing. A tubular case of the housing has an end having an upstream opening and another end having a downstream opening. The upstream opening of the case is adapted to introduce air into the housing. A cap is attached to the downstream opening of the case. An annular sealing portion, which is held between the case and the cap, is provided in the outer periphery of the air cleaning element. The case includes a case body having the downstream opening and a support plate attached to the downstream opening of the case body. The sealing portion is held between the support plate and the cap.

Abstract: An air cleaner includes a housing and a tubular air cleaning element, which is accommodated in the housing. A tubular case of the housing has an end having an upstream opening and another end having a downstream opening. The upstream opening of the case is adapted to introduce air into the housing. A cap is attached to the downstream opening of the case. An annular sealing portion, which is held between the case and the cap, is provided in the outer periphery of the air cleaning element. The case includes a case body having the downstream opening and a support plate attached to the downstream opening of the case body. The sealing portion is held between the support plate and the cap.

Abstract: A filter element has an upstream-side filter layer and a downstream-side filter layer. The downstream-side filter layer is attached to the upstream-side filter layer. The upstream-side filter layer has a coarser mesh than the mesh of the downstream-side filter layer. The upstream-side filter layer has a plurality of through-holes formed therein and extending throughout the thickness of the upstream-side filter layer. The plurality of through-holes allows the filter element to continue to be used when the rest of the upstream-side filter layer is clogged and the downstream-side filter layer still possesses filtering capability.

Abstract: A filter element has an upstream-side filter layer and a downstream-side filter layer. The downstream-side filter layer is attached to the upstream-side filter layer. A non-woven fabric made of resin fibers formed by a spinning process constitutes the upstream-side filter layer. The resin fibers have an average diameter within a range of 2.5 ?m and 10 ?m. The non-woven fabric has a weight per unit area within a range of approximately 2.5 g/m2 to 15 g/m2. The downstream-side filter layer has a finer mesh than the mesh of the upstream-side filter layer.

Abstract: A speed detector for detecting the speed of a moving body is of the type including a magnetic core, a detection coil wound about the core, a magnet with one pole thereof faced toward the periphery of the detection coil with a definite air gap therebetween, and means for relatively moving the magnet with respect to the core and the coil in accordance with the movement of the moving body. the magnet is arranged such that the magnetic flux produced thereby crosses the detection coil two times, thereby inducing a direct current voltage in the detection coil having a magnitude proportional to the speed of movement of the moving body and a polarity depending upon the direction of movement thereof.