PURPOSE: To simplify a mechanism and quicken telescopic movement and increase load resisting property and lengthen the span of life and miniaturize a device to lighten the weight by paying out or taking up a continuous body extending in the direction of an axial core fixed on a connecting pipe on the innermost side, to move connecting pipes telescopically.
CONSTITUTION: On the inner peripheries of pipes 1a to 1d except a pipe 1e on the innermost side, among the connecting pipes 1a to 1e fitted on each other telescopically, guide grooves 6a to 6d are arranged. Besides, the push-up sheet 7 of the band-shaped continuous body of high rigidity with the width made larger directed to the lower side so that both the end sections may be fitted on the grooves 6a to 6d at the time of extending, is composed. Then, the upper end of the push-up sheet 7 is firmly fitted on the pipe 1e, and the sheet 7 is payed out of a take-up machine 9, and is moved upward from the pipe 1e to the pipe 1b in order, and a mast is extended, and on the contrary, the sheet 7 is taken up and is shrunk. Besides, a one-piece-circular push-up sheet, a two- piece-symmetrical circular push-up sheet, or a caterpillar-shaped connecting sheet may be used to be composed.
ARAKI TOSHIMITSU
IIJIMA TOSHIKUNI
MIYASHITA KUNIHIRO
