Magnetosensitive latch engagement detector for a mechanical fastening system

摘要

A contactless latch engagement detector for a mechanical fastening system operating on the principle of magnetosensitivity. A magnetosensitive switch composed of a magnetosensitive device and at least one biasing magnet adjacent the magnetosensitive device are located in a buckle. Within or external to the buckle is an electronic circuit for driving the magnetosensitive device, and a flux bar composed of a ferromagnetic material having a high magnetic permeability is associated with a movable component of the system. In operation, the electronic circuit drives the magnetosensitive device, wherein its output is responsive to position of the flux bar relative to the magnetosensitive device. The flux bar moves responsive to position of a tongue within the buckle, whereby the fastened state of the mechanical (ie., seat belt) fastening system is detected when a predetermined output occurs.