Method and apparatus for retaining a core sample within a coring tool

摘要

The present invention provides a core sample retaining sleeve for preventing loss of a cut core sample from the distal end of a coring bit, particularly during retraction of the coring bit to within the coring tool. Preferably, the core sample retaining sleeve is disposed concentrically within the coring bit to fit around the received core sample. The core sample retaining sleeve has one or more retaining fingers formed on the distal end of the coring bit. The retaining fingers are selectively closeable, preferably by urging the one or more retaining fingers against one or more guide members. A guide member is preferably provided as a stationary ridge on the inner, distal surface of the coring bit. The core sample is contained and protected within the closed retaining sleeve.