Extendible dipper with extruded portion for a backhoe arm

Abstract

The invention relates to an extendible dipper assembly ( 32 ) for a backhoe arm for a construction equipment machine, said arm comprising a boom to be attached to the machine, and an extendible dipper assembly ( 32 ) articulated at the free end of the boom ( 30 ) for holding a working 38 tool, said extendible dipper assembly ( 32 ) comprising a proximal part ( 34 ) articulated to the boom ( 30 ) and a distal part ( 36 ) which is slidingly connected to the proximal part so as to form a length-adjustable dipper assembly, characterized in that at least one of the dipper parts ( 34, 36 ) comprises a rectilinear profile made by extrusion of metal, said profile having a closed cross-section around at least one inner cavity.

1 . Extendible dipper assembly for a backhoe arm for a construction equipment machine, the arm comprising a boom to be attached to the machine, and an extendible dipper assembly articulated at the free end of the boom for holding a working tool, the extendible dipper assembly comprising a proximal pact articulated to the boom and a distal part which is slidingly connected to the proximal part so as to form a length-adjustable dipper assembly, wherein at least one of the dipper parts comprises a rectilinear profile made by extrusion of metal, the profile having a closed cross-section around at least one inner cavity. 
     
     
         2 . Extendible dipper assembly according to  claim 1 , wherein the rectilinear profile comprises at least one rectilinear protrusion which extends outwardly in cross section and which forms a rail for slidingly connecting the proximal part to the distal part, the rectilinear protrusion being formed by extrusion together with the rectilinear profile. 
     
     
         3 . Extendible dipper assembly according to  claim 2 , wherein the rectilinear protrusion comprises at least one guiding surface which cooperates with a slide or a roller of the other part of the dipper for slidingly connecting the proximal part to the distal part, the guiding surface being directly obtained through the extrusion process. 
     
     
         4 . Extendible dipper assembly according to  claim 2 , wherein the rectilinear profile comprises two rectilinear protrusions which are located un-symmetrically with respect to a geometric axis of the cavity, and in that the rectilinear profile comprises at least one wall portion which is located substantially opposite the protrusions with respect to the cavity axis, the opposite wall portion having an increased thickness in comparison to at least one other wall portion of the profile. 
     
     
         5 . Extendible dipper assembly according to  claim 4 , wherein the rectilinear profile is substantially rectangular with two lateral wall portions extending along its longest dimension, a bottom wall portion and a top wall portion, in that the protrusions are located near the bottom wall portion, and in that the top wall portion has an increased thickness in comparison to the thickness of the bottom wall portion. 
     
     
         6 . Extendible dipper assembly according to  claim 1 , wherein the rectilinear profile is made of steel having an elastic limit of at least 240 MPa. 
     
     
         7 . Extendible dipper assembly according to  claim 1 , wherein the rectilinear profile is made of steel having an elastic limit of at least 360 MPa. 
     
     
         8 . Extendible dipper assembly according to  claim 1 , wherein the rectilinear profile is made of aluminium or of an aluminium alloy. 
     
     
         9 . Extendible dipper assembly according to  claim 1 , wherein the rectilinear profile is devoid of welding around its cross-section. 
     
     
         10 . Extendible dipper assembly according to  claim 1 , wherein the distal part of the dipper comprises a rectilinear profile made by extrusion of metal, the profile having a closed cross-section around at least one inner cavity.