1428634

Information

• Patent Grant
• 1428634

• References
• Source

• Patent Number

  1,428,634

• Date Filed

  Not available

• Date Issued

  Tuesday, September 12, 1922
  102 years ago

• CPC

  • E21F9/00 - Devices preventing sparking of machines or apparatus

• US Classifications

  • 299 - Mining or in situ disintegration of hard material