Patent ID: 7989991

Claim:
A linear actuator comprising an armature ( 16 ) and a stator ( 18 ), wherein: the armature ( 16 ) having at least two stacks ( 14 , 14 ′) of permanently magnetic rods ( 30 , 30 ′) arranged one over another; the stator ( 18 ) having magnetically conducting inner ( 50 , 50 a ) and outer ( 52 , 52 ′) areas; the stator is at least partly formed of a soft magnetic material, has at least one pair of teeth ( 22 a , 22 a ′; 22 b , 22 b ′; 22 c , 22 c ′; 22 d , 22 d ′; 22 e , 22 e ′; 22 f , 22 f ′) with teeth ( 22 ) opposite each other; each pair of teeth receiving a stack ( 14 , 14 ′) between them, forming an air gap ( 24 , 24 ′); the stator also having at least two magnetically conducting inner areas ( 50 , 50 a ), which at their ends facing the armature ( 16 ) have at least one of the teeth ( 22 ), and which are arranged at a predetermined distance (A) from each other in the direction of motion (B) of the armature ( 16 ), and which are at least partially surrounded by a substantially hollow cylindrical coil arrangement ( 60 , 60 a ); the hollow cylindrical coil arrangement having a central longitudinal axis (M) and magnetic flux which are oriented approximately transversely to the direction of motion (B) of the armature ( 16 ), and at least in sections essentially parallel to the central longitudinal axis of two teeth opposite each other of a tooth pair; wherein adjacent rods ( 30 , 30 ′) of a stack ( 14 , 14 ′) of the armature ( 16 ) have an alternating magnetic orientation (N->S, S<-N), and are essentially aligned with a central longitudinal axis (Z) of two mutually opposite teeth ( 22 ) of a tooth pair ( 22 a , 22 a ′; 22 b , 22 b ′; 22 c , 22 c ′; 22 d , 22 d ′; 22 e , 22 e ′; 22 f , 22 f ′); the inner areas ( 50 , 50 a ) of the stator ( 18 ) are between the stacks ( 14 , 14 ′) of the armature ( 16 ) and have teeth on their ends facing the stacks ( 14 , 14 ′); the stator ( 18 ) having at least two magnetically conducting outer areas which are outside the stack ( 14 , 14 ′) of the armature ( 16 ), and which have, at their ends facing the stacks ( 14 , 14 ′) of the armature ( 16 ), at least one of the teeth; the outer areas ( 52 ) of the stator ( 18 ) are comb-shaped and form a magnetic return path body in the direction of motion of the armature ( 16 ) and are in the form of C-shaped yokes which are plugged into each other, and each coil arrangement ( 60 , 60 a ) completely surrounds the appropriate one of the two inner areas ( 50 , 50 a ) of the stator ( 18 ).