AIR-CONTROL TELESCOPIC MAST Russian patent published in 2000 - IPC

FIELD: masts. SUBSTANCE: mast has remote-control locks for holding its sections in full-length position. Locks are provided with air cylinders whose rods carry fasteners; air cylinders communicate through adjustable valves with delivery spaces of mast sections. Locks are self-fixed in position by means of fasteners upon mast unfolding under the action of springs. For mast folding up compressed air is supplied to its spaces at pressure exceeding that required for its unfolding. In the process, adjustable valves open and pass air to air cylinders causing displacement of their pistons and unfastening of locks, Then air pressure is reduced and mast is folded up. EFFECT: improved reliability. 3 dwg