| 摘要 |
<p>PURPOSE:To eliminate installation of a hose reel, make the pipings compact, and reduce the cost on the whole device in a truck crane having booms capable of expansion/contraction in a plural stages by expanding/contracting the multi- stage booms in order by expansion cylinders provided between the expanding/ contracting booms. CONSTITUTION:A cylinder 6 for two-stage expansion is provided between a first boom 41 and a second boom 42, and a cylinder 7 for four-stage expansion is provided between a third boom 43 and a fourth boom 44. Between the first boom 41 and the third boom 43, and between the third boom 43 and a fifth boom 45 are connected by ropes 12, 16 for expansion and ropes 13, 17 for contraction. In the meanwhile, an oil pressure supplied from an oil pressure pump is supplied to the cylinders 6, 7 through hoses 20, 21, each cylinder 6, 7 is elongated, and the booms 42-45 are drawn by the ropes 12, 16 for expansion to be elongated to the first boom 41 in order. The hose 21 disposed in the booms 4 is guided by a hose sheave 23 to be supplied in order. Need of providing a hose reel for absorbing the expansion/contraction of the hose on the outer side of the booms is thus eliminated.</p> |
