3077741

Information

• Patent Grant
• 3077741

• References
• Source

• Patent Number

  3,077,741

• Date Filed

  Not available

• Date Issued

  Tuesday, February 19, 1963
  61 years ago

• CPC

  • E21D15/606 - the props being moved systematically

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 092 - Expansible chamber devices
  • 248 - Supports
  • 299 - Mining or in situ disintegration of hard material