3874178

Information

• Patent Grant
• 3874178

• References
• Source

• Patent Number

  3,874,178

• Date Filed

  Not available

• Date Issued

  Tuesday, April 1, 1975
  49 years ago

• CPC

  • E21D23/0454 - Trailing plates; Coal face or goaf side sprags
  • E21D23/0039 - and supported by a strut or by a row of struts parallel to the working face
  • E21D23/0427 - Shield operating devices; Hinges therefor

• US Classifications

  • 405 - Hydraulic and earth engineering