3564857

Information

• Patent Grant
• 3564857

• References
• Source

• Patent Number

  3,564,857

• Date Filed

  Not available

• Date Issued

  Tuesday, February 23, 1971
  53 years ago

• CPC

  • E21D23/0034 - comprising a goaf shield articulated to a base member
  • E21D23/0454 - Trailing plates; Coal face or goaf side sprags
  • E21D23/081 - forming parts of the roof supports
  • E21F15/02 - Supporting means

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 248 - Supports