Resources Contact Us Home
Rotary earth boring tool

Image Number 4 for United States Patent #4406332.

The present invention provides a nonstalling system for advancing a boring tool in situations where the inclination of the bore hole with respect to the vertical is such that the force of gravity does not provide effective forward thrust. A hydraulically powered marine screw propeller adjacent the boring tool provides the necessary thrust for the drilling operation. Pressurized drilling fluid provides the required hydraulic energy. The characteristics of the marine screw propeller are such that it provides maximum thrust at maximum rotative speed but should the tool stall the forward thrust drops to zero preventing stalling.

  Recently Added Patents
Feature-based autocorrection
Collaborative image capture
Motion compensated overlay
Sending targeted product offerings based on personal information
Dynamic load profiling in a power network
Matching geometry generation and display of mammograms and tomosynthesis images
  Randomly Featured Patents
Digital de-screening of documents
Apparatus and method for monitoring stored material
Optical sensing methods
Tire inflation apparatus with multiple inflation bells
Position measurement device, terminal provided therewith, and position measurement method
Arithmetic and control unit
Computer component torsional latching mechanism and method
Stepper motor with shaped memory alloy rotary-driver
Support harness
Temperature-compensated voltage level sense circuit