| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve working efficiency of a working machine provided with a rotary driving device rotatingly driving a drilling tool. <P>SOLUTION: The working machine includes: a rotary driving device rotatingly driving the drilling tool; a first winch hoisting up the rotary driving device; a second winch pulling down the rotary driving device; and a combined operation device simultaneously instructing the winding up operation of the first winch and the winding down operation of the second winch, and the winding down operation of the first winch and the winding up operation of the second winch, with one combined operation member. <P>COPYRIGHT: (C)2012,JPO&INPIT |
