Device actuated and maintained by axial pressure for mutual locking of tubular sections of a telescopic tube

摘要

A device for mutual locking concentrically, overlapping telescopic tubes which is actuated and maintained by axial pressure. The mutual locking device may be used to provide telescopic handles for floor brushes, brooms, mops and the like. An internal tubular section with a pin mounted to the end thereof is concentrically inserted within an external tubular section. A wedge-shaped tongue projects axially from the pin. Positioned circumferentially around the pin is an expansion bush provided with a wedge-shaped slot extending at least partially along the length of the bush and ending at a proximal end with asymmetrical entrance shoulders. Upon sliding the internal tubular section into the external tubular section, the tongue causes the bush to expand to lock the two tubular sections together by friction. The protruding entrance shoulder of the bush being offset in an axial direction relative to the other, ensures that torsional movement by the user causes the tongue to intercept the protruding shoulder while axial thrusts by the operator causes the tongue to slide further into the wedge-shaped slot, both of which actions cause the bush to expand further. As a result the bush diametrically expands causing the shell to contact the inner surface of the external tubular section generating friction which, in turn, mutually locks the tubular sections.