2218464

Information

• Patent Grant
• 2218464

• References
• Source

• Patent Number

  2,218,464

• Date Filed

  Not available

• Date Issued

  Tuesday, October 15, 1940
  84 years ago

• CPC

  • G05D23/2239 - using photoelectric elements

• US Classifications

  • 236 - Automatic temperature and humidity regulation
  • 250 - Radiant energy
  • 359 - Optical: systems and elements
  • 373 - Industrial electric heating furnaces