Moving Magnet Technologies (mmt)

Moving Magnet Technologies

Michaël Delbaere

Gaël Andrieux

Didier Frachon

Guillaume Loussert

Javier Rios-Quesada

Stéphane Biwersi

Yannick Ronnat

Gérald Masson

Lionel Billet

Jean-Daniel Alzingre

Thierry Dorge

Pascal Thibaut

Gaëtan Riou

Valentin Preault

A control device comprising at least one permanent magnet, and a mechanically guided member for enabling a relative movement between a. a first ferromagnetic structure, b. a second ferromagnetic structure comprising at least one electric coil, the electric coil modifying the magnetization state of the second ferromagnetic structure in accordance with the direction and the amplitude of the electric current flowing in the coil, the device furthermore comprising a position detection means for detecting the relative position of the first and second ferromagnetic structures, and a circuit for driving the supply current of the coil, which varies as a function of the signal delivered by the position detection means.

Control device comprising a mechanically guided member for enabling a relative movement

A module for detecting a rotating handle intended to be attached on a tube of a handlebar of a vehicle next to the handle includes a cylindrical magnet, a probe for detecting the magnetic field produced by the magnet, a support for the probe, a printed circuit board whereon the probe is secured, a support for the magnet and a flange used as a housing for the module. The magneto-sensitive probe detects rotation of the magnetic field emitted by the magnet and is secured to the handlebar, with the magnet and magnet holder being secured to the handle. The magnet and magnet holder form a cavity so that the inner radial surface of the magnet is positioned outside and opposite the magneto-sensitive probe. The magnet has a continuously variable magnetization direction so that the total rotation of the angle of the magnetic field generated by the magnet at the measuring point during the mechanical rotation of the handle is greater than 180&#xb0;.

Module for detecting a rotating handle of a motor vehicle

The disclosure relates to a valve for controlling the circulation of a fluid, having a valve body and a housing containing an electric motor composed of a stator and of a rotor, a needle, a sealing bell and also a fixed screw or a fixed nut. The fixed screw or the fixed nut is secured to the valve body, and the stator is secured to the valve body via the housing. The sealing bell is positioned at the interface between the rotor and the stator in such a way that the screw/nut, the rotor and the needle are within this bell and submerged in the fluid, the stator being isolated from the fluid. Furthermore, the rotor has the function of a nut or of a screw, and has a helical movement imposed by the fixed screw or the fixed nut and drives the needle axially. The motor is a brushless polyphase motor with radial principal magnetic flux.

Compact control valve

A linear electromagnetic actuator has a stroke c, with at least one stable position in one of the ends of the stroke, and includes: an armature made of a soft magnetic material, the armature being movable in an axial direction Y and having a length Hm in the direction Y, the armature having a symmetrical shape at the axis Y, and a stationary stator yoke made of a soft magnetic material and holding at least one electric coil. The actuator also includes at least one stationary permanent magnet that is magnetized along a transverse axis X perpendicular to the direction Y. The magnet is transversely placed between the movable armature and the electric coil. The magnet has a length Ha in the direction Y. The stationary yoke and the movable armature define therebetween at least one axial air gap. Ha+c is of the order of magnitude of Hm. The length Hm is such that 0.9&#xd7;(Ha+c)&#x3c;Hm&#x3c;1.1&#xd7;(Ha+c) so that, when the movable armature is in the end stability position thereof, one of the two axial ends of the movable armature is adjacent to one of the two axial ends of the permanent magnet.

Linear actuator with improved magnetic stability and stripping force

A positioning assembly includes a position sensor and a magnetic actuator, the actuator including a stator assembly formed of at least one ferromagnetic stator bearing at least one electric power supply coil and a yoke able to move relative to the stator assembly, the actuator having a geometry that is of revolution or periodic about an axis referred to as the main axis passing through the yoke, the sensor having at least one permanent magnet secured to the yoke and at least one magneto-sensitive probe that is fixed in relation to the magnet and able to measure the amplitude or direction of the magnetic field emitted by the magnet. The yoke has an interior recess including the main axis of the actuator, and the magnet is positioned inside the recess and secured to the yoke.

Compact positioning assembly comprising an actuator and a sensor built into the yoke of the actuator

The present disclosure relates to an electromagnetic actuator of the type producing a force due to the current that remains substantially constant over the entirety of its useful travel Y and that has a low force in the absence of current, including at least one stator structure, at least one electrical supply coil, and a moving member, the stator structure having, on the one hand, a central pole running perpendicular to the direction of the travel Y and having a width Yin the direction of the travel and terminating at its end in a width Ythat is greater than or equal to the travel Y of the moving member, Ybeing greater than Y, and, on the other hand, two lateral poles having widths Yin the direction of the travel and terminating at their end in a width Ygreater than Y.

Compact direct-drive actuator generating a constant force

The disclosure relates to a magnetic device for detecting the absolute position of an input shaft capable of rotating more than 360&#xb0;, the device including a main magnetic sensor, a motion reducer, and a secondary magnetic sensor, wherein the main magnetic sensor is connected to a rotor, measures the rotation of the shaft for ranges of angles of less than 360&#xb0;, and includes a main magnet, the motion reducer converts the rotation of the shaft into a reduced rotation, the maximum amplitude of which is equal to no more than 360&#xb0;, and the secondary magnetic sensor measures the reduced rotation and includes a secondary magnet. According to the disclosure, the secondary magnet is arranged between the upper and lower planes of the main rotor, and the main magnet has P pairs of poles, where P is greater than 1.

Growing community of inventors

Avanne-Aveney, France

Michaël Delbaere