3544075

Information

• Patent Grant
• 3544075

• References
• Source

• Patent Number

  3,544,075

• Date Filed

  Not available

• Date Issued

  Tuesday, December 1, 1970
  54 years ago

• CPC

  • E21C27/46 - by percussed planing means
  • B06B1/186 - operating with rotary unbalanced masses
  • E21C27/22 - by rotary drills with breaking-down means, e.g. wedge-shaped drills
  • E21C31/02 - for cutting or breaking-down devices

• US Classifications

  • 366 - Agitating
  • 175 - Boring or penetrating the earth
  • 299 - Mining or in situ disintegration of hard material