US 10,889,473 B2
Load crane main boom
Rossano Ceresoli, Ranica (IT); and Giovanni Fassi, Bergamo (IT)
Assigned to Fassi Gru S.P.A., Albino (IT)
Appl. No. 16/343,952
Filed by Fassi Gru S.P.A, Albino (IT)
PCT Filed Dec. 9, 2016, PCT No. PCT/EP2016/080413
§ 371(c)(1), (2) Date Apr. 22, 2019,
PCT Pub. No. WO2018/103859, PCT Pub. Date Jun. 14, 2018.
Prior Publication US 2019/0248630 A1, Aug. 15, 2019
Int. Cl. B66C 23/70 (2006.01); B66F 11/04 (2006.01)
CPC B66C 23/705 (2013.01) [B66C 23/701 (2013.01); B66F 11/046 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A load crane main boom comprising:
a tubular fixed first boom section, a tubular second boom section telescopically arranged and movable relative to the fixed first boom section between a retracted position and an extended position to define a moveable second boom section, and at least a tubular third boom section telescopically arranged and movable relative to the movable second boom section between a retracted position and an extended position to define a third moveable boom section;
a hydraulic system comprising:
a first cylinder-piston group axially extending within the main boom, integrally connected with the fixed first boom section and connected to the movable second boom section so as to move the moveable second boom section relative to the fixed first boom section under the action of a pressurized working fluid;
a second cylinder-piston group axially extending within the main boom, integrally connected with the movable second boom section and connected to the movable third boom section so to move the movable third boom section relative to the movable second boom section under the action of said pressurized working fluid;
a first opening and a second opening at the first cylinder-piston group for at least one of injecting pressurized working fluid into the hydraulic system or discharging pressurized working fluid from the hydraulic system;
a first tube and a sixth tube hydraulically connecting the first and the second cylinder-piston groups, the first tube and the sixth tube at least partially extending near the second cylinder-piston group along the axial direction and connected to the second cylinder-piston group in such a manner so that the first tube and the sixth tube form respective bends,
wherein the main boom further comprises:
a transversal second main rod connected to the second boom section supporting the second cylinder-piston group, and
a second reinforcing plate connected to the second boom section, comprising:
a first and second opposite lateral portions internally fixed to the second boom section and comprising through holes where the second main rod is arranged, to form first and second reinforcing elements for the second boom section;
a central portion connecting said first and second lateral portions and the central portion comprising a raised section, a lowered section and a section connecting the raised section and the lowered section;
a third reinforcing element having a through hole where the second main rod is arranged, said third reinforcing element being arranged in an intermediate position between the first lateral portion and the second cylinder-piston group,
wherein on a first side of the central portion, the third reinforcing element is positioned in correspondence of the raised section and the second cylinder-piston group is positioned in correspondence of the lowered section, said bends of the first and sixth tubes being inclined towards the third reinforcing element, and
wherein on a second side of the central portion, the first cylinder-piston group is positioned in correspondence of the raised section.