Method for monitoring elevator leveling performance with improved accuracy

A method for level monitoring of an elevator car within a hoistway at a plurality of floors, comprising the steps of:

• providing a plurality of sensed signals which further comprises the steps of:
• emitting light from an emitter which reacts with a plurality of light interactive regions of a target;
• emitting said light from said emitter which is absorbed by a plurality of light absorptive surfaces of said target;
• detecting said light after said light reacts with said plurality of said light interactive regions of said target by a corresponding detector, one or more of said corresponding detectors which detect said light from one or more said emitters and one or more of said emitters forming a sensor group;
• processing said plurality of sensed signals for providing a leveling variable, a floor number variable and a direction of travel variable which indicates a direction of travel of said elevator car within said hoistway by:
• determining a plurality of binary signals representing detection of said light emitted by one or more of said emitters and detected by one or more of said corresponding detectors within said sensor group;
• representing an absence of detected light by said corresponding detector from one or more said emitters within said sensor group as a logic 0 state of binary signals;
• representing a presence of detected light by said corresponding detector from one or more said emitters within said sensor group as a logic 1 state of said binary signals;
• calculating a sensor position of said sensor relative to said plurality of targets which is equivalent to said elevator position by maintaining a count of binary signals;
• determining said leveling variable, floor number variable and direction of travel variable from said count;
• synchronizing said count using one or more synchronization targets mounted within said hoistway at one or more of said plurality of floors which differ in a predetermined way from said plurality of targets;
• and
• storing said leveling variable, floor number variable and direction of travel variable at a remote elevator monitoring central processor.