PLUG INSERTION AND WITHDRAWAL DEVICE

PURPOSE:To enable elimination of a driving system consisting of a roller chain, an idler sprocket, ball screws and nuts, and so on to simplify the whole structure, and also to enable prevention of troubles such as parts failures. CONSTITUTION:Elevators 3 and 4 are actuated downward to bring a telescopic cylinder device 8 down to a hole 13 position, and then the telescopic cylinder device 8 is actuated in extending direction thereof to make plug catching nails 20 which are attached to an end pit of the cylinder, contact a plug 7 in the hole 13. After that, open/close driving devices 15 to 19 are actuated in closing direction thereof and the plug catching nails 20 are closed, to catch the plug 7, and thereafter the telescopic cylinder device 8 is actuated in shrinking direction thereof to bring out the plug 7 from the hole 13. And then, the elevators 3 and 4 are actuated in upward direction thereof to lift up the telescopic cylinder device 8 and the plug 7 to a bring-out position. When the plug 7 is inserted, the same procedures are performed in reverse sequences.