US PATENT SUBCLASS 431 / 79
.~.~.~.~ Photoelectric sensor

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


431 /   HD   COMBUSTION

18  DF  TIMER, PROGRAMMER, RETARDER OR CONDITION RESPONSIVE CONTROL {26}
75  DF  .~ By combustion or combustion zone sensor {2}
77  DF  .~.~ Of shutdown by response to sensed combustion failure or overheat {4}
78  DF  .~.~.~ By electrical control circuit {2}
79.~.~.~.~ Photoelectric sensor

DEFINITION

Classification: 431/79

(under subclass 78) Apparatus in which the sensor is a means responsive to electromagnetic waves produced by the burner flame.

SEE OR SEARCH CLASS

200, Electricity: Circuit Makers and Breakers,

61.02, for a light responsive switch.

250, Radiant Energy,

206+, for a residual photocell controlled circuit and subclass 215 for a photocell combined with a diverse type device.

318, Electricity: Motive Power Systems,

480, for an automatic or time delay control means responsive to radiant energy in which an electric motor is the ultimate and sole electrical device controlled.

361, Electricity: Electrical Systems and Devices,

173+, and 211 for an electric circuit having a photocell device in which the final element is an electro-magnet or a relay.