Supporting articles/loads

A locking arrangement for selectively preventing displacement of a tubular article/load support structure relative to an upstanding elongate support, the tubular support structure circumscribing the upstanding elongate support and adapted for lengthways displacement along upstanding elongated support, wherein the tubular support structure is provided with a first structure selected from a single tapered internally projecting lug, or a recess, a plurality of such lugs or recesses arranged around a predetermined region of the support structure, wherein the elongate support is provided with a complementary shaped structure adapted for respective engagement with said first structure of the tubular support structure in such manner as positionally to locate the support structure with respect to the elongated support when at a lowermost limit of downward movement, and wherein the tubular support structure incorporates a rigid containment attached securely to an internal tubular surface of the tubular support structure and opening towards the outer surface of the upstanding elongate support, and wherein said containment houses a closely fitting inflatable container mounting a friction member for co-operation with said outer surface in such manner that the inflatable container is contained on three sides of the containment but can expand outwardly to press the friction member against the outer surface of the elongate support in order to exert a grip on the elongate support to prevent lengthways displacement and thereby maintain the support structure and any article/load carried thereby in a required position relative to the elongate support with sufficient force to prevent torsional yawing of the tubular support structure about the elongate support.

A locking arrangement for selectively preventing displacement of a first tubular support structure relative to an upstanding elongate support, the tubular support structure being concentrically situated around the upstanding elongate support and displaceable lengthways of the upstanding elongate support comprising gripper devices arranged internally and concentrically of the tubular support structure, wherein said gripper devices are operable to cooperate with an outer surface of the upstanding elongate support between a non-gripping rest position in which the associated tubular support structure can be displaced lengthways of the elongate support, and an operated gripping setting in which the support structure is effectively locked against displacement relative to the elongate support in such manner as to prevent lengthways displacement and thereby maintain the support structure and any article/load carried thereby in a required position relative to the elongate support and with sufficient force to prevent torsional yawing of the tubular support structure about the elongate support, and apparatus coupled to the tubular support structure for supporting an article/load with respect to the upstanding elongate support, and including a second tubular structure circumscribing the elongate support for movement lengthways of the elongate support, the second tubular support structure being so interconnected with the first tubular support structure as enable the two tubular support structures to be alternately operated between the locking and unlocked settings at required lengthways positions thereof in such manner as to be able maintain the article/load at a required position relative to the elongate support.

An locking arrangement for selectively causing displacement of a first tubular support structure relative to a second tubular support structure and an upstanding elongate support, the first and second tubular support structures being concentrically situated around the upstanding elongate support and displaceable relative to the upstanding elongate support, the first and second tubular support structures comprising gripper devices arranged internally and concentrically of each tubular support structure, the gripper devices being operable to cooperate with an outer surface of the upstanding elongate support between a non-gripping rest position in which the associated tubular support structure can be displaced relative to the elongate support, and an operated gripping setting in which the associated tubular support structure is effectively locked against displacement relative to the elongate support in such manner as to prevent displacement and thereby maintain the support structure and any article/load carried thereby in a required position relative to the elongate support, and apparatus coupled to at least one of the tubular support structures for supporting an article/load with respect to the upstanding elongate support, the second tubular support structure being so interconnected with the first tubular support structure as enable the two tubular support structures to be alternately operated between the gripping and non-gripping settings at required positions in such manner as to turn one of the tubular support structures relative to the other through an angle about an axis of the elongate support.