| 摘要 |
<p>Pet door (10) has a frame (11) defining an access aperture (13) and a pivotally-hung aperture-closing flap (12) therein with a catch (14) to secure the flap against opening in one direction (A). The catch (14) is supported on a toggle joint (17) spring biased against one (36) of two adjacent abutments. The second abutment (60), which is displaceable, is normally positioned to prevent collapse of the toggle joint (17) whereby the catch (14) is maintained in a flap-securing position. The second abutment (60) is part of a magnetically-activated catch control mechanism, comprising (i) a rotationally mounted disc or lever (80) bearing the abutment and (ii) a rockable lever (64) interconnected with the disc (80). The rockable lever (64) bears magnet(s) (74) co-operable with a key magnet (66) on a pet collar. When the key magnet (66) is presented to the pet door (10), it repels the magnet(s) (74) on the rockable lever (64) causing the interconnected disc (80) to rotate, displacing the second abutment (60). A thrust in direction (A) on the flap (12) presses on the catch (14) and the latter then causes the toggle joint to collapse, disengaging the catch from the flap (12) and thus allowing the latter to open.</p> |
