Patent ID: 8646572

Claim:
An exhaust muffler for silencing exhaust gases, which have been introduced from a first side, and then discharging them to a second side opposite to the first side, which muffler comprises: a silencing chamber forming structure having first, second and third chambers disposed sequentially from the second side to the first side; an inlet tube having an inlet tube first end opening towards an outside of the silencing chamber forming structure and an inlet tube second end opening towards the first chamber after having sequentially passed through the third chamber and then through the second chamber as it extends from the inlet tube first end to the inlet tube second end; an outlet tube having an outlet tube first end opening towards the second chamber and an outlet tube second end opening to the outside of the silencing chamber forming structure after having passed through the first chamber as it extends from the outlet tube first end to the outlet tube second end; a first communicating passage communicating between the first chamber and the second chamber; and a second communicating passage communicating between the second chamber and the third chamber; in which a peripheral wall portion of the inlet tube, which is positioned in the third chamber, is formed with a vent hole for communicating a space within the inlet tube with the third chamber, and in which the exhaust gases passing through the first communicating passage are guided into the second chamber from the first side, and the exhaust gases passing through the second communicating passage are guided into the second chamber from the second side that is opposite to the first side to collide the respective exhaust gases from the first and second communicating passage.