Patent ID: 7695072

Claim:
Boom arrangement ( 1 ) for a scaling device including a scaling boom for supporting a scaling hammer, wherein the scaling boom is arranged for connection to a carrier vehicle, wherein: the scaling boom ( 4 , 5 ) is pivotally supported by a boom column unit ( 3 ), which is arranged for pivotal connection to the carrier vehicle, the boom column unit ( 3 ) includes a boom column ( 7 ), and extending at a distance from that element, a column bar unit ( 8 ), the boom column and the column bar unit are pivotally connected to a column link ( 9 ) for forming a four-link mechanism, the column link ( 9 ) supports a bearing for a boom lift cylinder ( 12 ), the bearing for the boom lift cylinder ( 12 ) is positioned for carrying a boom lift cylinder ( 12 ) which is positioned below the scaling boom ( 4 , 5 ) in operation, the boom column ( 7 ) is provided with a forked outer end portion ( 22 ) for pivotally enclosing the column link ( 9 ), and the scaling boom ( 4 , 5 ) is pivotally joined to the four-link mechanism in a pivot means ( 20 ) connecting the boom column ( 7 ) and the column link ( 9 ).