.~> With single light guide element to guide light in a continuous path {1}
DEFINITION
Classification: 250/900
OPTICAL LIQUID LEVEL SENSORS:
Art collection of liquid level sensor photocell systems which employ light conductors to detect the absolute or relative level of liquids.
(1) Note. To be classified herein, significant light conductor means must be recited in the claim(s).
SEE OR SEARCH CLASS
62, Refrigeration,
188, and 218+ for refrigeration means having liquid level control.
73, Measuring and Testing,
290+, especially subclass 293, liquid level or depth gauges combined with liquid level indicators for determining the level or depth of a body of liquid not otherwise classifiable. 116, Signals and Indicators,
109+, for liquid level alarms for indicating changes in liquid level; and subclasses 227+ for liquid level indicators. This class is directed to nonelectrical liquid level detectors but includes electrical indicating means.
137, Fluid Handling,
386, for liquid level responsive or maintaining systems which sense liquid level and exercise flow control; and subclasses 101.25+ for self-proportioning systems with liquid level sensing.
222, Dispensing,
64+, material level control systems.
340, Communications: Electrical,
619, for optical liquid level condition responsive systems responsive to liquid level and claiming a particular indicator means.
