3919930

Information

• Patent Grant
• 3919930

• References
• Source

• Patent Number

  3,919,930

• Date Filed

  Not available

• Date Issued

  Tuesday, November 18, 1975
  49 years ago

• CPC

  • E21F1/006 - Ventilation at the working face of galleries or tunnels
  • E21F17/02 - Suspension devices for tubes or the like

• US Classifications

  • 454 - Ventilation
  • 299 - Mining or in situ disintegration of hard material