1980135

Information

• Patent Grant
• 1980135

• References
• Source

• Patent Number

  1,980,135

• Date Filed

  Not available

• Date Issued

  Tuesday, November 6, 1934
  90 years ago

• CPC

  • E21C25/62 - Machines for making slits approximately perpendicular to the seams either level with, or above or below the level of, the machine

• US Classifications

  • 299 - Mining or in situ disintegration of hard material