Soil sample liner assembly having permanently attached core catcher for use in dual tube sampling system

Abstract

A soil sample liner assembly having a permanently attached core catcher is disclosed for use in a dual tube sampling system. The liner assembly includes a generally cylindrical tube having an upper end, a lower end, and a substantially smooth cylindrical outer surface extending between the ends. A core catcher is positioned within the tube and permanently attached at its lower end. The core catcher includes a plurality of resilient fingers that deflect outwardly to allow soil to pass into the tube and prevent soil from falling back out. The liner assembly has its lower end supported by an inner ledge of a cutting shoe of the dual tube sampling system. The liner assembly with the permanently attached core catcher is removable through the upper end of the outer casing without disturbing the attachment between the cutting shoe and the outer casing while the sampling system remains in the ground.

What is claimed is:  
     
         1 . A soil sample liner assembly for use in a soil sampling system, comprising: 
 a generally cylindrical tube having an upper end, a lower end, and a substantially smooth cylindrical outer surface extending between the upper and lower ends;    a core catcher positioned within said tube and permanently attached to said lower end of said tube, said core catcher comprising a plurality of inwardly and upwardly extending resilient fingers that deflect outwardly to allow soil to pass into said tube and to prevent soil from falling back out of said tube, said core catcher having an annular bottom which is substantially flush with the lower end of said tube.    
     
     
         2 . The soil sample liner assembly according to  claim 1 , wherein said resilient fingers form a dome shape within said tube.  
     
     
         3 . The soil sample liner assembly according to  claim 1 , wherein said tube and said core catcher are both made of thermoplastic material.  
     
     
         4 . The soil sample liner assembly according to  claim 3 , wherein said tube and said core catcher are welded together.  
     
     
         5 . A dual tube soil sampling system, comprising: 
 an outer tubular casing having an upper end and a lower end;    a cutting shoe attached to the lower end of said outer casing, said cutting shoe having an annular inner ledge;    a soil sample liner assembly placed within said outer casing, said liner assembly comprising a generally cylindrical tube having an upper end, a lower end, and a substantially smooth cylindrical outer surface extending therebetween;    said liner assembly further comprising a core catcher positioned within said tube and permanently attached to said lower end of said tube, said core catcher comprising a plurality of inwardly and upwardly extending resilient fingers that deflect outwardly to allow soil to pass into said tube and prevent soil from falling back out of said tube;    said liner assembly having its lower end supported by the inner ledge of said cutting shoe and being removable through the upper end of said outer casing without disturbing the attachment between the cutting shoe and the outer casing, whereby the liner assembly can be removed and replaced between successive sampling intervals while the cutting shoe and outer casing remain in the ground.    
     
     
         6 . The dual tube soil sampling system according to  claim 5 , further comprising an inner probe rod coupled to the upper end of said tube of said liner assembly, said inner probe rod being operable to raise and lower said liner assembly within said outer casing.  
     
     
         7 . The dual tube soil sampling system according to  claim 6 , further comprising a drive head positioned over the upper end of said outer casing, said drive head providing an impact surface for driving said soil sampling system into the ground.  
     
     
         8 . The dual tube soil sampling system according to  claim 6 , wherein said outer casing comprises a plurality of tubular members which are selectively connected together end-to-end to change a length of said outer casing, and said inner probe rod comprises a plurality of probe rods selectively connected together end-to-end to change a length of said inner probe rod, whereby a combined length of the inner probe rod and the soil sample liner assembly can be adjusted to approximately the same length as the outer casing when the soil sampling system is assembled.  
     
     
         9 . The dual tube soil sampling system according to  claim 6 , further comprising a solid drive point which can be interchanged with the soil sample liner assembly and connected to the lower end of the inner probe rod, said solid drive point being adapted to extend at least partially through the cutting shoe and seal a lower end of the outer casing to allow the sampling system to be driven to the top of an initial sampling interval which begins below the ground surface.  
     
     
         10 . The dual tube soil sampling system according to  claim 5 , wherein said core catcher has an annular bottom which is substantially flush with an outside profile of said tube.  
     
     
         11 . The dual tube soil sampling system according to  claim 5 , wherein said resilient fingers of said core catcher form a dome shape within said tube.  
     
     
         12 . The dual tube soil sampling system according to  claim 5 , wherein said tube and said core catcher are both made of thermoplastic material.  
     
     
         13 . The dual tube soil sampling system according to  claim 12 , wherein said tube and said core catcher are welded together.  
     
     
         14 . The dual tube soil sampling system according to  claim 5 , wherein said soil sample liner assembly is not attached to said outer casing or to said cutting shoe.  
     
     
         15 . A soil sample liner assembly for use in a dual tube soil sampling system, comprising: 
 a generally cylindrical tube having an upper end, a lower end, and a substantially smooth cylindrical outer surface extending between the upper and lower ends; and    a core catcher positioned within said tube and permanently attached to said lower end of said tube, said core catcher comprising a plurality of inwardly and upwardly extending resilient fingers that deflect outwardly to allow soil to pass into said tube and prevent soil from falling back out of said tube;    said core catcher having an annular bottom which is substantially flush with an outside profile of said tube, said liner assembly having a means at its lower end for engaging and resting on an annular inner ledge of a cutting shoe of the dual tube soil sampling system.    
     
     
         16 . The soil sample liner assembly according to  claim 15 , wherein said resilient fingers of said core catcher form a dome shape within said tube.  
     
     
         17 . The soil sample liner assembly according to  claim 15 , wherein said tube and said core catcher are both made of thermoplastic material.  
     
     
         18 . The soil sample liner assembly according to  claim 17 , wherein said tube and said core catcher are welded together.