Patent ID: 7404455
Filing Date: 2008-07-29
Classification: E02D

Abstract:
1. An apparatus for use with a penetration assembly for hammering a sampler into ground in a drill hole or born hole, the penetration assembly having; a sampler with a coupler at one end for connecting with a rod; a number of rods, each end of the rod having a coupler for coupling the rods together in series; an impact hammer apparatus that can be connected or disconnected to the top end of a number of the coupled rods in series and can drop the hammer to impact the top end from a constant height; a lifting device either for lifting the rod for coupling, decoupling, inserting and retrieving or for lifting the hammer to drop for hitting the top end of the coupled rods whose bottom end hammers the sampler repetitively; the apparatus comprising: a tip depth transducer that outputs a first electrical signal that is a function of the total length of the sampler and the rods coupled together in series passing through the tip depth transducer at a fixed reference point on the top of a drill hole; a shock force transducer that outputs a second electrical signal that is a function of the shock force in the rod and along the rod axial direction; a shock penetration transducer that outputs a third electrical signal that is a function of the penetration depth of the sampler due to a blow from the impact hammer dropped from a constant height; and a controller that receives and monitors the first, second and third signals, and that produces respective graph traces of functions of the sampler tip position, the rod shock force, and the sampler shock penetration depth.