Patent ID: 7847661

Claim:
An actuation magnet ( 2 ) for moving a closure needle of a hot-runner nozzle of an injection-molding tool, the actuation magnet comprising an armature ( 20 ) coupled in movement to a closure needle ( 18 ), the armature being displaceable between first and second cores ( 10 , 12 ) by subjecting at least one coil ( 6 , 8 ) to current, the armature ( 20 ) at a first axial end being designed as a flat armature and facing a correspondingly designed flat surface ( 24 ) of the first core ( 10 ), and the armature ( 20 ) at a second opposite axial end being designed as a cone armature and facing a correspondingly conically shaped surface of the second core ( 12 ), and a permanent magnet ( 32 ) arranged in a manner such that it exerts an additional magnetic force on the armature ( 20 ) in at least one movement direction (B, C), the actuation magnet ( 2 ) being bistable.