3837170

Information

• Patent Grant
• 3837170

• References
• Source

• Patent Number

  3,837,170

• Date Filed

  Not available

• Date Issued

  Tuesday, September 24, 1974
  50 years ago

• CPC

  • E21D23/0039 - and supported by a strut or by a row of struts parallel to the working face
  • E21D23/03 - having protective means

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 248 - Supports