Moving Magnet Technologies (mmt)

Stephane Biwersi

Didier Frachon

The invention relates to a contactless magnetic sensor for detecting a linear or angular position, comprising a moveable ferromagnetic element () the position of which is detected, and a stator assembly () itself, comprising two ferromagnetic parts (), defining with the moveable ferromagnetic element () two respective air gaps (), a permanent magnet () and a magneto-sensitive element () subjected to a magnetic field that depends on the position of the moveable ferromagnetic element () and designed to deliver a measurement signal that depends on the magnetic field to which it is subjected. According to the invention, the two ferromagnetic parts () define therebetween a third air gap (), the permanent magnet () being rigidly connected only to the first ferromagnetic part () and the magneto-sensitive element () being placed in the third air gap ().

Position sensor using a moveable ferromagnetic element

The invention relates to an electromagnetic actuator comprised of a mobile assembly, a fixed ferromagnetic stator assembly, at least one electric field coil, and of at least one permanent magnet, having two stable positions of equilibrium without current at its ends of travel. The invention is characterized in that the mobile assembly has two distinct ferromagnetic armatures placed on both sides of the stator assembly and each forms, together with the stator assembly, at least one magnetic circuit, and is characterized in that the permanent magnet magnetically cooperates with one of the other ferromagnetic mobile parts in a stable position of equilibrium without current at the end of travel.

Quick-action bistable polarized electromagnetic actuator

A position sensor, which can detect a steering column twist of a first magnetic rotoric structure including a plurality of radially oriented magnets and a second statoric structure including two concentric gear rings extended by radially oriented teeth. The rotoric structure is substantially disc-shaped and includes a ferromagnetic head supporting the plurality of magnets, the statoric structures are provided with interleaving teeth and the position sensor includes a third collector structure including two flow closing parts, one of which is fixed, and which define at least one air gap in which at least one magnetosensitive element is arranged.

Growing community of inventors

Besancon, France

Stephane Biwersi