Patent ID: 6236125
Filing Date: 2001-05-22
Classification: H02K

Abstract:
A linear and single-phase polarized electromagnetic actuator comprising:a wound stator and at least one portion which is movable along an axis OX, with a useful travel Xc,i) said stator of soft magnetic materials having two poles,A) each with a width at least equal to the useful travel Xc,B) spaced apart by a distance Xo,C) disposed in a same plane surface parallel to the axis OX, andD) polarized with opposite sign by at least one coil,ii) each said portion which is movable with current energizing the coil, in a direction that depends on a sign of the current, being provided with a moving ferromagnetic yoke of soft magnetic material and at least one magnet connected to said yoke,a) said yoke being provided, facing the stator, with three portionsa1) parallel to said poles of the stator,a2) being displaced parallel to said poles,a3) at a constant minimum distance Yo measured perpendicular to the axis OX for the closest portion or portions,b) said at least one magnet havingb1) poles parallel to [the] said poles of the stator, andb2) a same thickness L measured perpendicular to the axis OX, each portion being further characterized in that;c) said at least one magnet of one moving portionc1) is partly embedded in a cavity of the moving yoke on one side of said poles of the stator, to a depth e such that 0.1 L<e<0.9 L,c2) is displaced with said yoke parallel to said poles of the stator at a minimum constant distance (E-L) wherein E is a distance measured perpendicular to the axis OX between the poles of the stator and a bottom of the cavity, andc3) has magnetization which is perpendicular to the axis OX and, in case of a plurality of magnets, is in a same direction,d) said yoke has a length measured along the axis OX at least equal to 3 Xc+Xo and is situated at a minimum distance from the stator equal to Yo=E-e, which is greater than E-L.