| 摘要 |
PURPOSE:To prevent the shift of front gap and to keep sufficient reproducing output, by providing a space specifying the lower end of gap constituting surface and a bonding layer linking the space and a winding hole, between the front gap constituting surface of a magnetic core and the winding hole. CONSTITUTION:Filling-in grooves 11, 12 for adhesives are provided on one side of a sendust core block 10 to fill in silver solders 13, 14. The preventing groove 15 silver solder diffusion for and winding groove 16 are provided. The groove 15 specifies the lower end of a front gap constituting surface 17 with a groove ridge 15a. The depth of the groove 16 is made to the depth >=3 times the groove 11. Further, after polishing the process surface of the block 10 and providing the spacer such as SiO2 on the front gap constituting surface 17 and the back gap constituting surface 19, another core semisphere block is molten and bonded to form the magnetic tape slide surface. Thus, the forming of the diffusion layer 20 on the surface 12 at bonding the adhesives layer 18 is prevented at the groove 15. Thus, without giving effect on the magnetic characteristics, strong bonding is made with no front gap shifted. Then, sufficient number of coil windings can be assured to the groove 16 to avoid the output from being lowered. |
