Abstract: A magnetic field sensing device in the form of a sensor unit which reduces the effective air gap between the sensing device and its exciter is provided by packaging the sensing device in the manner that provides protection from the environment while simultaneously minimizing the distance between the sensing device and its exterior surface adjacent its exciter. The present invention is particularly suitable for automotive applications, such as magnetic field sensing devices for detecting the wheel speed for an electronic anti-lock braking system.

Abstract: A package for a magnetic field sensitive element, such as a magnetoresistor, includes at least two planar layers of a relatively stiff ferromagnetic material which is also electrically conductive. The layers have opposed edges which are in closely spaced relation to form a narrow gap therebetween. A terminal tab is integral with and extends from each layer. A magnetic field sensitive element is on a surface of at least one of the layers and preferably extends across the gap to be on both layers. The magnetic field sensitive element has a pair of contacts each of which is electrically connected to a separate one of the layers. A permanent magnet is mounted on and insulated from the surface of the layers opposite the magnetic field sensitive element. A protective layer of an insulating material may cover the magnetic field sensitive element and the layers with the terminal tabs extending therefrom.

Abstract: A piezoelectric knock sensor has a case comprising a mounting stud, flexing plate and cover. The flexing plate has a surface provided with a plurality of raised radial ridges. A piezoelectric disk is affixed to the surface with an adhesive and abuts the ridges for improved strain transmission and reliable electrical ground contact. A spring contact further biases the disk against the ridges during assembly bonding of the adhesive; and excess adhesive can flow radially outward between the ridges.