Method for locking a telescopic suction tube inner and outer tubes has a longitudinal groove in the inner tube with holes in which a ball in a control block on the outer tube engages

摘要

The inner tube (1) has a recessed groove (13) along part of the outer surface in which a number of holes (11) are placed at regular intervals into which a ball (7) engages to prevent further extension. The ball is releasable by sliding a control (8) on the outer tube (2) to disengage a locking arm (6).