2689721

Information

• Patent Grant
• 2689721

• References
• Source

• Patent Number

  2,689,721

• Date Filed

  Not available

• Date Issued

  Tuesday, September 21, 1954
  70 years ago

• CPC

  • E21C27/46 - by percussed planing means
  • Y10T74/18544 - Rotary to gyratory

• US Classifications

  • 299 - Mining or in situ disintegration of hard material
  • 074 - Machine element or mechanism