1654643

Information

• Patent Grant
• 1654643

• References
• Source

• Patent Number

  1,654,643

• Date Filed

  Not available

• Date Issued

  Tuesday, January 3, 1928
  97 years ago

• CPC

  • A47G29/1225 - Signalling devices
  • A47G2029/1226 - comprising electrical parts
  • A47G2029/1228 - activated by the weight of the letter

• US Classifications

  • 200 - Electricity: circuit makers and breakers
  • 340 - Communications: electrical