Double acting jack for drilling platforms - has reducing gear supported by telescopic rods for pinions actuating rack

摘要

The jack is driven by a brake motor (5) through a reducing gear (4) and a pinion (1) acting on a rack forming part of the platform leg (2). Telescopic rods (6,7) are fixed to the platform (8) at pivots (14,13) mounted on brackets (9,10), and to the gear casing (3) by a pivot (18) on one rod (6) and by brackets (21,20) perpendicular to the axis of the second rod (7). The line of action of the telescopic rods (6,7) passes through the pitch point of the pinion.