3441317

Information

• Patent Grant
• 3441317

• References
• Source

• Patent Number

  3,441,317

• Date Filed

  Not available

• Date Issued

  Tuesday, April 29, 1969
  55 years ago

• CPC

  • E21D17/0206 - Hydraulically operated extension devices
  • E21C27/01 - specially adapted for removing overhanging coal
  • E21D23/063 - Retractable cantilever extensions therefor

• US Classifications

  • 299 - Mining or in situ disintegration of hard material
  • 405 - Hydraulic and earth engineering