| 摘要 |
PURPOSE:To judge the limit of life of a head due to wear accurately and easily by providing a conductor pattern for detection, which extends up to the inside of a magnetic gap depth width in the front end side of a lower magnetic material at least, on the lower magnetic material. CONSTITUTION:When the first coil conductor 4 is patterned by etching on an insulating layer 2 of a lower magnetic substrate 1 whose surface the first insulating layer 2 is formed by adhesion, a conductor pattern 5 for detection which extends into a magnetic gap depth width D in the front end side of the lower magnetic substrate 1 is provided near this coil conductor 4, and a current is flowed to a detecting part 6 from a lead part 7 simultaneously with power-on of a device body of a recording and reproducing device or the like. According as the depth width is reduced by wear of the tape sliding face of the head due to tape running, the width of the detection part 6 of the conductor pattern 5 for detection is reduced gradually, and the detecting part 6 is worn to disappear, and the current is not flowed to the conductor pattern 5 for detection, and the thin film magnetic head is replaced then. |
