3104731

Information

• Patent Grant
• 3104731

• References
• Source

• Patent Number

  3,104,731

• Date Filed

  Not available

• Date Issued

  Tuesday, September 24, 1963
  61 years ago

• CPC

  • E04B9/0421 - comprising ducts
  • E04B9/045 - being laminated
  • E04B9/0457 - having closed internal cavities
  • E04B9/0464 - having irregularities on the faces
  • E04B9/0485 - containing a filling element

• US Classifications

  • 181 - Acoustics
  • 052 - Static structures
  • D25 - Building units and construction elements