Fall prevention safety device for head-carrying carriages of drilling machines

Abstract

A fall prevention safety device for the head-carrying carriage of drilling machines, includes a safety cable constrained between the carriage (C) and a rotating drum suitable for winding the safety cable. The drum rotates according to the translation of the head-carrying carriage in such a way as to maintain the safety cable constantly tight, so that when the drive chain is no longer tight, the safety cable holds the carriage and prevents it from falling down.

The invention claimed is: 
     
         1 . A fall prevention safety device (D) for a head-carrying carriage (C) of drilling machines, wherein said carriage (C) translates on at least one guide-rail (A 1 ) of a drilling mast (A), a translation of said head-carrying carriage being controlled by at least one motor unit (M) with at least one driving pinion (M 1 ) of a drive chain, said safety device (D) comprising:
 at least one safety cable (F) directly or indirectly constrained between said head-carrying carriage (C) and at least one rotating drum (T);   wherein said at least one rotating drum (T) for winding said safety cable (F) is mounted in proximity to the motor unit (M) of the guide-rail (A 1 ) of the drilling mast (A), and   wherein said drum (T) rotates according to the translation of said head-carrying carriage (C) in such a way as to maintain said safety cable (F) constantly tight, so that when said drive chain is no longer tight said safety cable (F) holds said carriage (C) and prevents said head-carrying carriage from falling down.   
     
     
         2 . The fall prevention safety device (D) according to  claim 1 , wherein said drum (T) is mechanically connected to said motor (M) of a drilling machine. 
     
     
         3 . The fall prevention safety device (D) according to  claim 2 , wherein said drum (T) is mounted coaxial with a rotation axis (X) of said driving pinion (M 1 ). 
     
     
         4 . The fall prevention safety device (D) according to  claim 3 , wherein said drum (T) is connected to a same rotor shaft (M 2 ) as said pinion (M 1 ). 
     
     
         5 . The fall prevention safety device (D) according to  claim 1 , wherein a winding diameter (P) of said safety cable (F) on said drum (T) is substantially equal to a pitch diameter of said pinion (M 1 ). 
     
     
         6 . The fall prevention safety device (D) according to  claim 1 , wherein a said safety cable (F) is constrained to said head-carrying carriage (C) through at least one elastic compensator device (E) that cushions movements of the head-carrying carriage (C) with respect to said safety cable (F). 
     
     
         7 . The fall prevention safety device (D) according to  claim 1 , wherein a motorized rotation of said drum (T) causes said safety cable (F) to be wound or unwound, and consequently causes said head-carrying carriage (C) to translate.