초록 ▼

An electro-magnetically controlled pet door having a door (1) pivotally mounted in a door aperture (17) of a frame (2) and an electrically controlled catch mechanism normally preventing opening of the door in at least one direction that is released when a magnet (30) carried by an animal approaching

An electro-magnetically controlled pet door having a door (1) pivotally mounted in a door aperture (17) of a frame (2) and an electrically controlled catch mechanism normally preventing opening of the door in at least one direction that is released when a magnet (30) carried by an animal approaching the door is sensed by two or more reed switches (23,24) on or in the frame mounted and connected electrically in parallel. The switches (23,24) are disposed in an array extending circumferentially of said door aperture and have normally open contacts and magnetic biasing means (26,27) are associated with the reed switches and positioned laterally thereof to increase their sensitivity.

대표청구항 ▼

1. An electro-magnetically controlled pet door comprising a door pivotally mounted in a door aperture in a frame, an electrically controlled catch mechanism normally preventing opening of the door in at least one direction that is released when the presence of a magnet carried by an animal approachi

1. An electro-magnetically controlled pet door comprising a door pivotally mounted in a door aperture in a frame, an electrically controlled catch mechanism normally preventing opening of the door in at least one direction that is released when the presence of a magnet carried by an animal approaching the door is sensed by a sensor comprising two or more reed switches on or in the frame connected electrically in parallel, said switches being disposed in an array extending circumferentially of said door aperture and having normally open contacts, the contacts of one or more of the switches closing in the presence of a magnet carried by an animal, wherein the pet door also includes magnetic field producing biasing means operable to increase the sensitivity of the reed switches to an animal borne magnet, said magnetic field producing biasing means comprises first and second magnets located beyond respective ends of the sensor and displaced transversely therefrom so as to produce a flux path extending along said sensor between the pole of the first magnet and the pole of the other magnet facing the sensor so that the contacts automatically open again when the presence of the magnet carried by the animal is no longer sensed by the reed switches.