Prop

Abstract

Prop, extendable by means of the removal of an inner tube coaxially disposed in an outer base tube, equipped with a safety device which prevents the complete separation of both tubes and which comprises connection means between the tubes, which prevent their separation but allow the movement of the lower end of the inner tube between two fixed points, the first of which is disposed on the inside of the base tube, as the second point is determined by the length of said connection means, since the connection means are composed of a thin and elongated connection element, such as a rod, a cable or similar, disposed lengthways on the inside of the base tube, with one end attached thereto and with the opposite end inserted into the inner tube, equipped with a stop block which prevents its removal from the inner tube.

1 . Prop ( 1 ), particularly applicable to formworks, extendable by means of the removal of an inner tube ( 2 ) coaxially disposed in an outer base tube ( 3 ), which comprises securing means of the position of said inner tube with regards to the outer base tube and a safety device which prevents the total separation of both tubes when the securing means are not operational, characterised in that the safety device comprises connection means ( 12 ) between the two tubes, which prevent their separation but permit the movement of the lower end ( 7 ) of the inner tube ( 2 ) between two fixed points, the first point whereof is disposed in the inside of the outer base tube ( 3 ), as the second point is determined by the length of said connection means.  
   
   
       2 . Prop ( 1 ) according to  claim 1 , characterised in that the connection means ( 12 ) are composed of a thin, elongated connection element, such as a rod, a cable or similar, longitudinally disposed on the inside of the outer base tube ( 3 ), the first end ( 17 ) of the connection element being removably fixed on one end of said outer tube ( 3 ), while the opposite end ( 18 ), inserted in the inner tube ( 2 ), is equipped with a stop block ( 6 ) which prevents its removal from the inner tube by colliding with a retaining element joined to the lower end, preventing the exit of the stop block ( 6 ) from the inside of the inner tube.  
   
   
       3 . Prop ( 1 ) according to  claim 2 , characterised in that the retaining element is formed by a lid ( 8 ), which is equipped with a through-hole ( 9 ) whose diameter is less than that of the stop block ( 6 ), which allows the connection element ( 12 ) to pass through it but which prevents the stop block ( 6 ) from passing through it.  
   
   
       4 . Prop ( 1 ) according to  claim 2 , characterised in that the inner tube ( 2 ) is equipped with a second through-hole ( 10 ) on one side, adjacent to the orifice ( 9 ) of the lid ( 8 ), preferably with a section the same as that of the stop block ( 6 ) and connected to said orifice by the lid through a slot ( 11 ), considerably wider than that of the connection element ( 12 ).  
   
   
       5 . Prop ( 1 ) according to  claim 3 , characterised in that the inner tube ( 2 ) is equipped with a second through-hole ( 10 ) on one side, adjacent to the orifice ( 9 ) of the lid ( 8 ), preferably with a section the same as that of the stop block ( 6 ) and connected to said orifice by the lid through a slot ( 11 ), considerably wider than that of the connection element ( 12 ).