1644834

Information

• Patent Grant
• 1644834

• References
• Source

• Patent Number

  1,644,834

• Date Filed

  Not available

• Date Issued

  Tuesday, October 11, 1927
  97 years ago

• CPC

  • B61L5/1836 - using light sources of different colours and seperate optical systems

• US Classifications

  • 246 - Railway switches and signals
  • 340 - Communications: electrical
  • 362 - Illumination