3802520

Information

• Patent Grant
• 3802520

• References
• Source

• Patent Number

  3,802,520

• Date Filed

  Not available

• Date Issued

  Tuesday, April 9, 1974
  50 years ago

• CPC

  • B23B51/0406 - Drills with a tubular body
  • B28D1/041 - with cylinder saws
  • E21B10/02 - Core bits
  • E21B10/48 - the bit being of core type
  • B23B2222/56 - Non-specified metals
  • B23B2226/75 - Stone, rock or concrete
  • B23B2251/54 - Drilling tools having provision for drilling different diameters
  • B23B2270/14 - Constructions comprising exactly two similar components
  • Y10T408/375 - Coaxial tools
  • Y10T408/45 - including Tool with duct
  • Y10T408/895 - Having axial, core-receiving central portion

• US Classifications

  • 175 - Boring or penetrating the earth
  • 408 - Cutting by use of rotating axially moving tool