3891275

Information

• Patent Grant
• 3891275

• References
• Source

• Patent Number

  3,891,275

• Date Filed

  Not available

• Date Issued

  Tuesday, June 24, 1975
  49 years ago

• CPC

  • E21D23/0427 - Shield operating devices; Hinges therefor
  • E21D23/0039 - and supported by a strut or by a row of struts parallel to the working face

• US Classifications

  • 299 - Mining or in situ disintegration of hard material
  • 405 - Hydraulic and earth engineering