1801974

Information

• Patent Grant
• 1801974

• References
• Source

• Patent Number

  1,801,974

• Date Filed

  Not available

• Date Issued

  Tuesday, April 21, 1931
  93 years ago

• CPC

  • B61L7/083 - Common line wire control using currents of different amplitudes, polarities, frequencies, or the like

• US Classifications

  • 246 - Railway switches and signals