MAGNETIC REVOLUTION COUNTER AND METHOD FOR DETERMINING NUMBERS OF REVOLUTIONS THAT CAN BE DETERMINED BY MEANS OF SAID REVOLUTION COUNTER

摘要

The invention relates to a magnetic revolution counter and to a method for determining a specifiable quantity n of revolutions of an external magnetic field that are to be determined, said external magnetic field produced by a rotating element (4), or a quantity n of magnetic poles of a rotating pole wheel, which quantity of magnetic poles can be moved past, or a linear magnetic scale that can be moved past, containing a revolution sensor (2), which contains magnetic domain-wall conducting tracks, which consist of open spirals or multiply wound loops closed in themselves, which are formed by a GMR layer stack or a soft magnetic layer having locally present TMR layer stacks and into which magnetic 180° domain walls can be introduced and - by measurement of the electrical resistance of specifiable spiral sections or loop sections - can be located, wherein a single domain wall is introduced into the domain-wall conducting tracks or at least two magnetic domain walls are introduced into the domain-wall conducting tracks in such a way that the at least two domain walls are brought into a defined distance of greater than 360° from each other, with respect to the location change thereof from a first to a second position in the event of rotation of the external magnetic field by the angle of greater than 360°, and are lastingly thus spaced apart from each other and wherein electrical contacts arranged in a defined manner are provided on the domain-wall conducting tracks, which electrical contacts, together with associated domain-wall conducting track sections covered thereby, are interconnected to form separate but jointly readable Wheatstone half-bridges, wherein the resistance ratios determined by the Wheatstone half-bridges are stored as a signal level completely in a memory (9) as a table, which memory can be continuously compared with table-like target value patterns stored in a further memory (10) for each permissible revolution i (0 i n) in order to determine the number of revolutions and, for the number of revolutions i to be determined, the number of revolutions for which the measured resistance ratios match the target value pattern in the memory (10) is output, determined by a corresponding processing unit (11).