2677535

Information

• Patent Grant
• 2677535

• References
• Source

• Patent Number

  2,677,535

• Date Filed

  Not available

• Date Issued

  Tuesday, May 4, 1954
  70 years ago

• CPC

  • E21D15/606 - the props being moved systematically
  • E21D15/603 - by means of hydraulic devices
  • E21D17/00 - Caps for supporting mine roofs
  • E21D17/01 - characterised by the shape of the cap

• US Classifications

  • 299 - Mining or in situ disintegration of hard material
  • 173 - Tool driving or impacting
  • 175 - Boring or penetrating the earth
  • 198 - Conveyors: power-driven
  • 405 - Hydraulic and earth engineering