1378830

Information

• Patent Grant
• 1378830

• References
• Source

• Patent Number

  1,378,830

• Date Filed

  Not available

• Date Issued

  Tuesday, May 17, 1921
  103 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