919422

Information

• Patent Grant
• 919422

• References
• Source

• Patent Number

  919,422

• Date Filed

  Not available

• Date Issued

  Tuesday, April 27, 1909
  115 years ago

• CPC

  • E21C27/122 - with breaking-down members having a striking action

• US Classifications

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