| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the following problem that a slit is directed to the center side and an upper side, and a suction flow passage of exhaust gas is vertically linear, so that a collision degree of the exhaust gas against a partition annular wall portion is small. <P>SOLUTION: An inner circumferential edge part in a top ring 5 is formed as a downward inclined portion 17 to the center side, the diameter of an upper end portion of an inner box 4 is gradually enlarged upward, a circumferential wall portion 29 in a partition annular wall portion 15 is formed with a tapered surface 31 whose diameter is reduced downward in an intermediate part according to an enlarged diameter shape of the inner box, the inside diameter of a portion below the tapered surface 31 is set to be smaller than a portion above the tapered surface, the inside diameter of the top ring 5 is set to be smaller than an upper opening diameter of the inner box 4, an upper end part of the inner box 4 is positioned below the inner circumferential edge part of the top ring 5, and an exhaust gas suction portion is set to be an exhaust gas suction slit 20 formed between the inner circumferential edge part of the top ring 5 and the upper end part of the inner box 4, so that the exhaust gas suction slit 20 is directed to the center side and a lower side. Thereby, an obliquely upward flow is deflected downward just after suction, and a subsequent exhaust gas suction flow passage 18 becomes a curved shape, so that a lot of exhaust gas is collided against a crowned member, the partition annular wall portion 15, and the inner box 4. <P>COPYRIGHT: (C)2012,JPO&INPIT |
