Locking pin for shoring support structure

Abstract

A locking pin 240 for an extendable structure, such as a acrow prop, having a first protrusion 244 and a second protrusion 248 extending from the shaft 242 of the pin, the first protrusion 244 extending from an intended lower surface of the shaft and having a curved inner wall facing towards the centre of the shaft and the second protrusion 248 extending from an intended upper surface of the shaft 242 and forming a box-like structure having a recess 245 for receipt of a leash 250.

1 . A locking pin for an extendable structure comprising:
 an elongated shaft member, the shaft member having at least one protrusion extending from an intended upper or lower surface thereof.   
     
     
         2 . The locking pin as claimed in  claim 1 , wherein two protrusions extend from the shaft member wherein a first protrusion extends from an intended lower surface of the shaft member and a second protrusion extends from an intended upper surface of the shaft member. 
     
     
         3 . The locking pin as claimed in  claim 1 , wherein the shaft member and protrusions are formed of a load bearing metallic material, selected from forged or machined steel. 
     
     
         4 . The locking pin as claimed in  claim 1 , wherein the first protrusion has an inner wall facing towards the centre of the shaft and an opposing outer wall, the inner and outer walls defining opposing side walls. 
     
     
         5 . The locking pin as claimed in  claim 4 , wherein the outer wall extends substantially perpendicularly to the longitudinal axis of the shaft and wherein the inner facing wall is curved. 
     
     
         6 . (canceled) 
     
     
         7 . The locking pin as claimed in  claim 5 , wherein the radius of curvature corresponds substantially to a curvature of an inner tube of a shoring structure in relation to which the locking pin is to be used. 
     
     
         8 . The locking pin as claimed in  claims 4 , wherein the inner and outer facing walls of the first protrusion extend across the whole of the underside of the shaft, i.e., at the point where it meets the shaft the protrusion has a width corresponding substantially to the diameter of the shaft. 
     
     
         9 . The locking pin as claimed in  claims 4 , wherein each side wall of the protrusion tapers to an apex at the end of the protrusion. 
     
     
         10 . The locking pin as claimed in  claims 2 , wherein the second protrusion extends substantially perpendicularly from an intended upper surface of the shaft, the protrusion being spaced laterally from the first protrusion towards an outer end of the shaft. 
     
     
         11 . The locking pin as claimed in  claim 2 , wherein the second protrusion forms a box-like structure having four sides extending upwardly from the shaft, wherein the width of each side is slightly less than the diameter of the shaft, the protrusion having a slight tapering towards it free end. 
     
     
         12 . (canceled) 
     
     
         13 . The locking pin as claimed in  claims 2 , wherein the second protrusion has a recess or hole through its centre for receipt of a leash. 
     
     
         14 . (canceled) 
     
     
         15 . The locking pin as claimed in  claim 2 , wherein the second protrusion has a recess or hole through its centre for receipt of a leash, wherein the leash is formed from a wire. 
     
     
         16 . The locking pin as claimed in  claim 2 , wherein the second protrusion has a recess or hole through its centre for receipt of a leash, and the leash extends upwardly from the protrusion and shaft. 
     
     
         17 . The locking pin as claimed in  claims 2 , wherein the second protrusion has a recess or hole through its centre for receipt of a leash, wherein the leash is provided with a loop spaced apart from the shaft. 
     
     
         18 . The locking pin as claimed in  claim 2 , wherein the second protrusion has a recess or hole through its centre for receipt of a leash, wherein the leash is provided with a loop spaced apart from the shaft and the loop is formed by the provision of a ferrule which is cold formed onto the junction of the loop of the leash. 
     
     
         19 . The locking pin as claimed in  claim 1 , wherein one or both ends of the elongated shaft includes a taper for mating with a central bore of a pinion gear. 
     
     
         20 . An extendable structure comprising:
 an outer tube having a threaded region with opposing longitudinal slots therethrough;   an inner tube slidable within the outer tube and having a plurality of pairs of transverse holes at spaced apart intervals;   a locking pin according to  claim 1 , the pin being receivable through the slots of the outer tube and a pair of transverse holes of the inner tube; and   a collar mounted on the threaded region and being rotatable to raise and lower the pin within the slots, the protrusion of the pin being received between the collar and the inner tube;   wherein the collar includes a driven member for mating with a driving member connectable to an actuator, actuation of the driving member causing rotation of the driven member to effect rotation of the collar.   
     
     
         21 . The extendable structure as claimed in  claim 20 , wherein the driven member is a bevel gear provided on an upper or lower surface of the collar and the driving member is a pinion gear that meshes with the bevel gear provided on the collar, the pinion gear receiving an end of the locking pin. 
     
     
         22 . The extendable structure as claimed in  claim 21 , wherein an outer surface of the pinion gear is provided with a recess or protrusion for mating with a corresponding protrusion or recess of an actuator. 
     
     
         23 . A kit of parts for adapting an existing extendable structure, particularly but not exclusively a shoring support structure, the kit comprising a collar with a bevel gear on an upper or lower surface thereof, a locking pin according to claims and a pinion gear.