Methods and apparatus for detecting refrigerator door openings

Communications: electrical – Condition responsive indicating system – Specific condition

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C340S686100, C049S013000

Reexamination Certificate

active

07005983

ABSTRACT:
A detection apparatus for detecting refrigerator door openings is coupled to at least one switch configured to be activated by a door opening. When the door is opened, the switch is activated and inputs a signal to the detection apparatus. The detection apparatus rectifies the signal; and phase-shifts the rectified signal so that it leads or lags the line voltage. The shifted output signal is fed to a processor that detects the opening of the door based upon the shifted signal. Signals output by a plurality of switches that generate a signal when activated mixed using an opto-coupler. Relative impedance of the lead and lag circuits may be adjusted to differentiate a phase shift of one shifted signal relative to another signal. The processor converts a value in degrees of phase shifting of the mixed signal to a time value, and based upon the time value, the processor determines which of the doors is open.

REFERENCES:
patent: 3996434 (1976-12-01), Griffin
patent: 4241337 (1980-12-01), Prada
patent: 4463348 (1984-07-01), Sidebottom
patent: 4566285 (1986-01-01), Tershak et al.
patent: 4691195 (1987-09-01), Sigelman et al.
patent: 4707684 (1987-11-01), Janke et al.
patent: 4891626 (1990-01-01), Neuman
patent: 5063372 (1991-11-01), Gillett
patent: 5070319 (1991-12-01), Scuka
patent: 5142822 (1992-09-01), Beckerman
patent: 5317115 (1994-05-01), Forsberg
patent: 5396217 (1995-03-01), Proefke et al.
patent: 5887446 (1999-03-01), Lee

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Methods and apparatus for detecting refrigerator door openings does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Methods and apparatus for detecting refrigerator door openings, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods and apparatus for detecting refrigerator door openings will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3704800

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.