Abstract: A controllable muffler system is sued for use with an engine that produces a power by burning fuel. The system comprises a first passage section extending from the engine for having an exhaust gas of the engine flow therethrough. The first passage section has a catalytic converter mounted thereon. The system further comprises a dual passage section including second and third passage sections which extend separately from an end of the first passage section. The second passage has a control valve for controlling the flow rate of the exhaust gas flowing therethrough. The system further comprises a fourth passage section extending from respective ends of the second and third passage sections to the open air. The fourth passage section has a rear muffler mounted thereon. The system further comprises a control unit which controls the control valve of the second passage section in accordance with an operation condition of the engine.

Abstract: A controllable muffler system is sued for use with an engine that produces a power by burning fuel. The system comprises a first passage section extending from the engine for having an exhaust gas of the engine flow therethrough. The first passage section has a catalytic converter mounted thereon. The system further comprises a dual passage section including second and third passage sections which extend separately from an end of the first passage section. The second passage has a control valve for controlling the flow rate of the exhaust gas flowing therethrough. The system further comprises a fourth passage section extending from respective ends of the second and third passage sections to the open air. The fourth passage section has a rear muffler mounted thereon. The system further comprises a control unit which controls the control valve of the second passage section in accordance with an operation condition of the engine.

Abstract: A flexible connection tube for an automotive exhaust system comprises a flexible metal bellows adapted to be connected between a run of exhaust piping for absorbing expansion or contraction of the exhaust piping, and an outer knitted metal-wire braid covering the outer periphery of the bellows for protecting the bellows from damage and for preventing the bellows from stretching to its full length. The outer knitted metal-wire braid is formed into a substantially cylindrical shape by knitting plural metal-wire bundles (each bundle being produced by a plurality of parallelly bonded metal wires) alternately with each other in spiral directions with respect to the axial direction of the bellows. Apertures are defined by many groups of four adjacent metal-wire bundles knitted alternately with each other.

Abstract: A controllable exhaust system of an internal combustion engine is shown which includes an exhaust gas inlet tube extending from the engine, a muffler connected at its inlet side to the exhaust gas inlet tube and having first and second exhaust gas flowing passages defined therein, and first and second exhaust gas outlet tubes respectively connected to the first and second exhaust gas flowing passages and extending from the muffler independently. A muffler controller is incorporated with the exhaust system for varying the flow passage area of the second exhaust gas outlet tube in accordance with the pressure of the exhaust gas led into the muffler from the engine.

Abstract: A muffler assembly, for an exhaust system of an internal combustion engine has an exhaust gas inlet tube projected into the muffler to feed the muffler with the exhaust gas of the engine. First and second flow passages are defined through which the exhaust gas from the muffler flows independently before discharged to the open air. The controller has a pneumatic actuator that has a piston rod and a work chamber. The piston rod is adapted to reciprocate linearly in accordance with the magnitude of pressure developed in the work chamber. The pressure of the exhaust gas of the engine is fed to the work chamber of the pneumatic actuator. The actuator controls a valve assembly which includes a valve plate and a pivot shaft through which the valve plate is pivotally installed in the second flow passage of the first means.

Abstract: An exhaust system of an internal combustion engine has an exhaust gas inlet tube extending from the engine. A muffler is connected at its inlet side to the exhaust gas inlet tube. The muffler includes first and second exhaust gas flowing passages. First and second exhaust gas outlet tubes are respectively connected to the first and second exhaust gas flowing passages and extend from the muffler independently. A flow controller steplessly varies the flow passage area of the second exhaust gas outlet tube in accordance with the pressure of the exhaust gas discharged from the engine. The flow controller continuously increases the flow passage area with increase of the magnitude of the exhaust gas pressure.