A tractor including: an engine mounted on a traveling body; a post-processing device configured to purify exhaust gas of the engine; and a tail pipe long in an up-down direction and configured to emit exhaust gas having passed through the post-processing device to the outside. The post-processing device is arranged in a standing posture in front of an operation unit on the traveling body so that the exhaust gas flows from the bottom to the top. An upwardly protruding outlet pipe is provided on an upper surface side of the post-processing device. The inner diameter of an exhaust gas inlet side of the tail pipe is set larger than the outer diameter of the outlet pipe which is inserted and communicated with the exhaust gas inlet side of the tail pipe.

Provided is a tail pipe in which a silencing effect at a discharge port is obtained. One aspect of the present disclosure is a tail pipe including: an inner tube including a discharge port configured such that an exhaust gas is discharged therefrom; an outer tube arranged so as to form a space between the outer tube and the inner tube by surrounding an outer peripheral surface of the inner tube, an upstream end of the outer tube in a flow direction of the exhaust gas being closed; and at least one communication hole allowing communication between an interior of the inner tube and the space.

A muffler includes a first tube defining a first inlet for receiving exhaust and a first outlet. The muffler includes a housing defining a tuning chamber. The muffler includes a second tube at least partially received within the first tube. Further, the second tube defines a second inlet disposed within the first tube and a second outlet disposed in fluid communication with the tuning chamber. The muffler further includes a muffler outlet for discharging exhaust from the muffler. Moreover, the first tube and the second tube define an annular passage therebetween. The annular passage is disposed in fluid communication with the first outlet of the first tube and the muffler outlet.

An exhaust system for an internal combustion engine and having at least an exhaust duct, which originates from the internal combustion engine and has an end part, which ends with an outlet opening, through which exhaust gases are released into the atmosphere. The end part of the exhaust duct has at least one movable wall, which can be moved to different positions to vary the width of the outlet opening. There are provided a motor-driven actuator device, which is configured to move the movable wall and can be electronically controlled, and a control unit, which is configured to vary, by controlling the actuator device, the position of the movable wall depending on a rotation speed of the internal combustion engine and on an engine load of the internal combustion engine.

An exhaust system for an internal combustion engine and having at least an exhaust duct, which originates from the internal combustion engine and has an end part, which ends with an outlet opening, through which exhaust gases are released into the atmosphere. The end part of the exhaust duct has at least one movable wall, which can be moved to different positions to vary the width of the outlet opening. There are provided a motor-driven actuator device, which is configured to move the movable wall and can be electronically controlled, and a control unit, which is configured to vary, by controlling the actuator device, the position of the movable wall depending on a rotation speed of the internal combustion engine and on an engine load of the internal combustion engine.

A tractor including: an engine mounted on a traveling body; a post-processing device configured to purify exhaust gas of the engine; and a tail pipe long in an up-down direction and configured to emit exhaust gas having passed through the post-processing device to the outside. The post-processing device is arranged in a standing posture in front of an operation unit on the traveling body so that the exhaust gas flows from the bottom to the top. An upwardly protruding outlet pipe is provided on an upper surface side of the post-processing device. The inner diameter of an exhaust gas inlet side of the tail pipe is set larger than the outer diameter of the outlet pipe which is inserted and communicated with the exhaust gas inlet side of the tail pipe.

A tractor including: an engine mounted on a traveling body; a post-processing device configured to purify exhaust gas of the engine; and a tail pipe long in an up-down direction and configured to emit exhaust gas having passed through the post-processing device to the outside. The post-processing device is arranged in a standing posture in front of an operation unit on the traveling body so that the exhaust gas flows from the bottom to the top. An upwardly protruding outlet pipe is provided on an upper surface side of the post-processing device. The inner diameter of an exhaust gas inlet side of the tail pipe is set larger than the outer diameter of the outlet pipe which is inserted and communicated with the exhaust gas inlet side of the tail pipe.

A tractor including: an engine mounted on a traveling body; a post-processing device configured to purify exhaust gas of the engine; and a tail pipe long in an up-down direction and configured to emit exhaust gas having passed through the post-processing device to the outside. The post-processing device is arranged in a standing posture in front of an operation unit on the traveling body so that the exhaust gas flows from the bottom to the top. An upwardly protruding outlet pipe is provided on an upper surface side of the post-processing device. The inner diameter of an exhaust gas inlet side of the tail pipe is set larger than the outer diameter of the outlet pipe which is inserted and communicated with the exhaust gas inlet side of the tail pipe.

A tractor including: an engine mounted on a traveling body; a post-processing device configured to purify exhaust gas of the engine; and a tail pipe long in an up-down direction and configured to emit exhaust gas having passed through the post-processing device to the outside. The post-processing device is arranged in a standing posture in front of an operation unit on the traveling body so that the exhaust gas flows from the bottom to the top. An upwardly protruding outlet pipe is provided on an upper surface side of the post-processing device. The inner diameter of an exhaust gas inlet side of the tail pipe is set larger than the outer diameter of the outlet pipe which is inserted and communicated with the exhaust gas inlet side of the tail pipe.

A muffler includes a first tube defining a first inlet for receiving exhaust and a first outlet. The muffler includes a housing defining a tuning chamber. The muffler includes a second tube at least partially received within the first tube. Further, the second tube defines a second inlet disposed within the first tube and a second outlet disposed in fluid communication with the tuning chamber. The muffler further includes a muffler outlet for discharging exhaust from the muffler. Moreover, the first tube and the second tube define an annular passage therebetween. The annular passage is disposed in fluid communication with the first outlet of the first tube and the muffler outlet.