| 摘要 |
PROBLEM TO BE SOLVED: To solve problems that exhaust gas and outer air do not flow smoothly, and there are a large number of components and much smear by grease. SOLUTION: This top ring includes: a crowned member 1 located above a gap between an inner circumference face of an opening 9 of a table 7 and an upper part of an inside box 10; an inner circumference annular wall 2 which is continuously formed downward from the edge of the inner circumference of the crowned section 1 and whose lower edge section is overlapped with the upper part of the inside box 10; and a partition annular wall 3 of an upper part in a suction space 11, which is located outside of the inner circumference annular wall 2 and whose upper end is integrated with the lower face of the crowned member 1. Two or more exhaust gas sucking holes 4, 4a... are formed above the upper end of the inside box 10 which is overlapped with the inner circumferential annular wall 2. The outer air is sucked through an outer air sucking opening 5 formed by attaching this top ring to an outer part 11b of the suction space 11. The inside and outside walls of the partition annular wall 3 is made vertical so as to reduce its resistance for smooth flow of the exhaust gas and the outer air. Exhaust gas is prevented from contacting with the outside of the partition annular wall 3, which is a part of the top ring, by making the crowned member 1, inner circumference ring wall 2, and partition annular wall 3 into a single component. COPYRIGHT: (C)2010,JPO&INPIT |
