Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Continuously monitored supplemental obstruction detector for garage door operator










Image Number 4 for United States Patent #5191268.

An automatic door operator with a continuously monitored supplemental obstruction detector. In a first embodiment, the obstruction detector is a radiant beam obstruction detector that transmits a beam of modulated radiant energy across the door opening. A safety signal generator produces an active safety signal only on unobstructed receipt of radiant energy by a receiver. Failure to receive the active safety signal when the motor is closing the door at least stops the door. A two wire cable, which carries both power and the active safety signal, connects the supplemental obstruction detector to the automatic door operator. Constant activation of a portable transmitter or of a local push button can override the supplemental obstruction detector to close the door. An alternative supplemental obstruction detector includes a safety edge having a compressible tube disposed on a leading end of the door. Plural conductors change their conductive state upon compression of the compressible tube. This embodiment may include a delay upon detection of compression of the compressible tube so that contact with the floor is not detected as an obstruction.








 
 
  Recently Added Patents
Image forming apparatus assembled with a fixing member and a pressing member
Medical capsule housing formed by thermal welding
Apparatus and method for layered decoding in a communication system using low-density parity-check codes
Interferer region identification using image processing
Eyeglasses
Integrated emergency medical database system
Tactile output device for computing device notifications
  Randomly Featured Patents
Electric heater
Dry spinning process for producing zein fibers
Methods and systems for providing improved handoffs in a wireless communication system
Electrical connector with programmable lead frame
Import/export utility and a method of processing data using the same
Prestressing apparatus
Intra-pair differential skew compensation method and apparatus for high-speed cable data transmission systems
Jug with water filter
Combination miniature cable connector and antenna
Toothed gear transmission having two partial transmissions disposed parallel to each other in the power flow