1731576

Information

• Patent Grant
• 1731576

• References
• Source

• Patent Number

  1,731,576

• Date Filed

  Not available

• Date Issued

  Tuesday, October 15, 1929
  95 years ago

• CPC

  • E21D3/00 - Raising shafts

• US Classifications

  • 173 - Tool driving or impacting
  • 299 - Mining or in situ disintegration of hard material