BOOM OF WORK MACHINE

PROBLEM TO BE SOLVED: To provide a boom of a work machine, which can curtail time and labor of disassembly and assembly thereof during transportation and storage, or at the time of starting field work, facilitate transportation and enhance economization. SOLUTION: According to the structure of the boom of the work machine, an intermediate boom 9 is formed of a lower half portion 9a having a bracket 17 for connecting a boom cylinder 12, and an upper half portion 9b having a bracket 21 for connecting a boom cylinder 13. Then the lower half portion 9a and at least one side surface of the upper half portion 9b of the intermediate boom 9 are connected together by means of pins 28, and pins 31 for connecting both of the other side surfaces together are detachably arranged on the other side. Further the connection by means of the pins 31 is canceled, and the upper half portion 9b is rotatably foldable on the lower half portion 9a about the pins 28. In this manner the lower half portion 9a and the upper half portion 9b are folded on each other about the pins 28, and while a divided boom 8d of a lower boom 8, a boom 10a of an upper boom 10, and the boom cylinders 12, 13 are attached to the lower and upper half booms, the whole boom can be transported or stored. COPYRIGHT: (C)2009,JPO&INPIT