To prevent failure of a working device caused by a damage of hose or the like.
A working stand 17 includes a working stand outside main body part 21 of a bottomed vessel shape attached on a tip part of a boom and including a bottom part 21a and a circumference wall part 21b rising upward from a circumference edge part of the bottom part 21a, and a liner 25 detachably attached inside of the working stand outside main body 21. The working device 50 operating with receiving hydraulic pressure is attached on an upper of the circumference wall part 21b of a tip side of the working stand outside main body 21 and an operation control valve 55 controlling supply and discharge of hydraulic fluid to control operation of the working device 50 is attached on an inside wall surface of the circumference wall part 25c of a tip end side of the liner 25. A supply hose 59 supplying hydraulic fluid to the operation control valve 55 is extended to a port side along an upper surface of the circumference wall part 25c.
NAKABAYASHI SHUJI
MUTO OSAMU
