3604754

Information

• Patent Grant
• 3604754

• References
• Source

• Patent Number

  3,604,754

• Date Filed

  Not available

• Date Issued

  Tuesday, September 14, 1971
  53 years ago

• CPC

  • E21D3/00 - Raising shafts

• US Classifications

  • 299 - Mining or in situ disintegration of hard material
  • 175 - Boring or penetrating the earth