Door chime

Communications: electrical – Condition responsive indicating system – Specific condition


Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0


340384E, 340527, 340693, G08B 1308




An audio signal device for a door mounted advertising display, the device includes a signal unit, a battery connected to said signal unit, the unit including a tone generator, a pulse generator connected to control the tone generator, a timer connected to control the time of operation of the pulse generator, and a motion switch connected to energize the timer in response to the motion of the door, the timer further including a circuit for preventing reactivation of the timer for a predetermined period of time.

patent: 4258358 (1981-05-01), Lee et al.
patent: 4435701 (1984-03-01), Baon
patent: 4772879 (1988-09-01), Hein


Say what you really think

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


Door chime does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Door chime, we encourage you to share that experience with our community. Your opinion is very important and Door chime will most certainly appreciate the feedback.

Rate now


Profile ID: LFUS-PAI-O-1733145

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