Step-up type magnetic head

Claim 1

A step-up type magnetic head, comprising: a first plate having a planar first side surface and a second side surface which are substantially narrower than planar principal surfaces of the first plate and which define an edge at a portion thereof at which they intercept one another; a thin film magnetic head core formed on said first side surface of said first plate and having a substantially closed magnetic circuit including a gap, a pole tip surface of said head core extending to said edge defined by said first side surface and said second side surface; a plurality of thin film magnetic layers formed on said first side surface of said first plate at a position adjacent to said magnetic head core but remote from said edge defined by said first side surface and said second side surface; a closed-loop thin film coil formed over said thin film magnetic layers and extending through said magnetic circuit of said head core; a second plate having a substantially planar third side surface and a fourth side surface which are substantially narrower than planar principal surfaces of said second plate, said third side surface being provided with a groove which extends from one principal surface of said second plate to another principal surface of said second plate, said second plate having a magnetic part and a non-magnetic part, said magnetic part occupying a portion of said second plate including an entire inner wall of said groove and a part of said third side surface adjacent said groove, said non-magnetic part occupying a portion of said second plate including said fourth side surface, said magnetic part of said second plate contacting said thin film magnetic layers to form a substantially closed transformer magnetic circuit which encompasses said groove; a transformer secondary bulk winding, said secondary winding being divided into a first portion wound around said first plate through said groove and a second portion wound around said second plate through said groove, said first portion and said second portion of the secondary winding being connected in a balanced winding manner, said secondary winding being electromagnetically coupled with said thin film coil through said transformer magnetic circuit; wherein said second side surface of said first plate and said fourth side surface of said second plate form a substantially continuous operative surface of the head, said operative surface being a surface which in operation of the head for recording and/or reproduction faces a magnetic recording medium.