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
Switched capacitor hold-up scheme for constant boost output voltage
Method and system for providing an intelligent visual scrollbar position indicator
Device and implantation system for electrical stimulation of biological systems
Wireless control system for a patient support apparatus
Selective thermal treatment of medical instrument portions with thermal treatment system instrument holder
Controller for internal combustion engine
Dental composition, kit of parts and use thereof
  Randomly Featured Patents
Adaptive slant range compensator for a remote optical mapping system
Belt conveyor with belt reinforcing member
Porous amorphous silica-alumina refractory oxides, their preparation and use as separation membranes
Line interface circuit
Ice cream cone and popsicle holder
Magnesium A-zeolite for nitrogen adsorption
Socket
Removal of Hg, NO.sub.x, and SO.sub.x with using oxidants and staged gas/liquid contact
Semiconductor device with plural power supply circuits, plural internal circuits, and single external terminal
Method of etching a lens for a semiconductor solid state image sensor