3851431

Information

• Patent Grant
• 3851431

• References
• Source

• Patent Number

  3,851,431

• Date Filed

  Not available

• Date Issued

  Tuesday, December 3, 1974
  50 years ago

• CPC

  • B28B23/005 - with anchoring or fastening elements for the shaped articles
  • B28B7/225 - for making stairs or stair units comprising more than one step
  • E04F11/028 - having a central stringer
  • E04F11/116 - of stone, concrete or like material or with an upper layer of stone or stone like material
  • E04F2011/0209 - mainly of metal

• US Classifications

  • 182 - Fire escape, ladder, or scaffold
  • 052 - Static structures