Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1997-07-28
1999-01-26
Le, Que
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
49 31, G01V 904
Patent
active
058641343
ABSTRACT:
A garage door opener is retrofitted with a device that causes a garage door to close after it has been open for a predetermined amount of time. In a garage door of the type having a light that is activated when the door is opened or closed, a photocell is mounted in close proximity to the light to detect the presence or absence of light. When light is detected, the photocell conducts and prevents a first automatic switch, such as a silicon-controlled rectifier, from conducting. When absence of light is detected, the first automatic switch closes and a capacitor discharges through the first automatic switch and throws a second automatic switch, such as a transistor, that is electrically connected in parallel to a manually-operated switch for opening and closing the garage door. When the second automatic switch conducts, it mimics closing of the manually-operated switch and thus effects closing of the garage door. The circuit is enabled by a spring-loaded plunger that holds a pair of electrical contacts apart from one another only when the door is open.
REFERENCES:
patent: 5752343 (1998-05-01), Quintus
Le Que
Smith Ronald E.
LandOfFree
Automatic garage door closing device with a door position detect does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic garage door closing device with a door position detect, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic garage door closing device with a door position detect will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1452058