2138478

Information

• Patent Grant
• 2138478

• References
• Source

• Patent Number

  2,138,478

• Date Filed

  Not available

• Date Issued

  Tuesday, November 29, 1938
  86 years ago

• CPC

  • G03B21/34 - Change-over arrangements

• US Classifications

  • 352 - Optics: motion pictures
  • 200 - Electricity: circuit makers and breakers