Fall protection device

Abstract

A fall protection device including a frame including a vertical stanchion, a boom and a strut, wherein the strut has a male unit extending into an opening formed at a female unit, the units cooperating and sliding with respect to each other at the level of the opening when a compression force is transmitted to an end of the trust. The female unit is provided with housings for respective cylindrical or spherical elements that roll or rotate by friction with the male unit when the male and female units slide with respect to each other, the dimensions of the elements being such that they interfere with the outer profile of the male unit, pressing and causing the successive plastic deformation of the male unit during its movement relative to the female unit.

1 . A fall protection device comprising a frame including a vertical stanchion rotatably mounted in a support casing, a boom connected to a top portion of the vertical stanchion, and a strut having a first end connected to an upper portion of the stanchion and a second end connected to the boom in order to cushion the pivotal movement of the boom towards the stanchion caused by a downward traction force occasionally applied at a distal end of the boom, wherein the strut has a male unit extending into an opening formed at a female unit, said units cooperating and sliding with respect to each other at the level of the opening when a compression force is transmitted to the second end of the trust, and wherein the female unit is provide with housings for respective cylindrical or spherical elements that roll or rotate by friction with the male unit when the male and female units slide with respect to each other, the dimensions of said elements being such that they interfere with the outer profile of the male unit, pressing and causing the successive plastic deformation of the male unit during its movement relative to the female unit. 
     
     
         2 . A fall protection device according to  claim 1 , wherein the male and the female units of the trust respectively consist of an inner and an outer concentric tubular sections designed to slide into one another. 
     
     
         3 . A fall protection device according to  claim 2 , wherein the inner and the outer tubular sections have essentially quadrangular cross sections, and wherein the cylindrical or spherical elements are four, each one facing a respective face of the inner tubular section. 
     
     
         4 . A fall protection device according to  claim 2 , wherein the outer tubular section has drill holes through which a minor portion of respective spherical elements extends towards the interior of the outer tubular section to contact the inner tubular section, each spherical element being enclosed, over an associated drill hole and with the capacity of rotation, within a housing. 
     
     
         5 . A fall protection device according to  claim 4 , wherein the housings for the spherical elements consist of respective concave and originally separated parts firmly coupled to the exterior surface of the outer tubular section and dimensioned to accommodate the respective spherical element. 
     
     
         6 . A fall protection device according to  claim 4 , wherein the drill holes are truncated-cone hole shaped, comprising an internal opening facing the interior of the outer tubular section and an external opening facing the housing, the internal opening having a smaller cross section than the external opening. 
     
     
         7 . A fall protection device according to  claim 1 , wherein the boom is pivotally connected to the top portion of the vertical stanchion. 
     
     
         8 . A fall protection device according to  claim 6 , wherein the first and second ends of the strut are pivotally connected to the upper portion of the stanchion and to the boom, respectively.