| 摘要 |
1308586 Luffing booms for workmen VEREINIGTE FLUGTECHNISCHE WERKEFOKKER GmbH 26 Nov 1971 [28 Nov 1970] 54992/71 Heading B8H The orientation of the intermediate section 7 of a 3-section articulated boom and of a workman's support 9 mounted at the outer end of the boom are maintained constant throughout the range of movements of the boom. The support 9 is pivotally mounted on the boom section 8 and is secured to a sprocket 11 which is connected by an endless chain 12 to a sprocket 10 secured to the boom section 7 concentrically with the pivot axis of the section 8. The section 8 is luffed with respect to the section 7 by means of an hydraulic ram 13 pivotally connected between a lever 15 and links 14, connected between the sections. The lever 15 is pivoted on the boom section 7 and is secured to a gear-wheel 16 which meshes with a gear-wheel 17 secured to the arm 5<SP>1</SP> of the boom section 5. The boom section 5 consists of parallelogram arms 5<SP>1</SP>, 511 pivotally connected between the boom section 7 and a support 3 rotatably mounted on a vehicle, an hydraulic ram 6 being connected between the support 3 and the arm 5<SP>1</SP>. |
