| 摘要 |
<P>PROBLEM TO BE SOLVED: To easily move to an isolated position even when a mobile duct is arbitrarily moved while securing a sufficient communication state needed for dust collection at a communication position, in a dust collecting duct to be positioned at the communication position at which openings of a fixed duct and the mobile duct are made to face each other and turned to the state of being communicated with each other and the isolated position at which the ducts are isolated from each other. <P>SOLUTION: On the tip end of the mobile duct 12, an expansion part 20 which is expandable in the axial direction and is turned to an expanded state when a load is not applied, and a flange 21 at the tip end of the expansion part 20 are provided. The fixed duct 11 is provided with a flange part 22 having a slope 22a flared in the radial direction and formed so as to widen a facing distance with the flange 21 as approaching an edge part. When the mobile duct 12 is moved from the isolated position to the communication position, the edge part 21e of the flange 21 gets on the slope 22a of the flange part 22 of the fixed duct 11, and the expansion part 20 is shortened by the action of pressurizing force in the axial direction. <P>COPYRIGHT: (C)2013,JPO&INPIT |
