Abstract: A double-head magnetic transducer assembly for use in a helical scan type tape recorder which comprises first and second magnetic heads secured to a head base so as to be successively arranged in spaced relationship to each other in the direction of transport of a magnetic tape. Each of the first and second magnetic heads has I-shaped and L-shaped core halves which are coupled to each other to form a magnetic gap and the length of the I-shaped core half in the direction of rotation of the transducer assembly is arranged to be above 0.175 millimeters.

Abstract: A perpendicular magnetization type magnetic head comprises a main magnetic pole part wound with a coil, for subjecting a magnetic recording medium to magnetic fluxes which pass perpendicularly through a magnetic layer of the magnetic recording medium, a non-magnetic part located on both sides of the main magnetic pole and adjacent to the magnetic recording medium, so as to sandwich the main magnetic pole, and a closed magnetic path forming magnetic pole part for forming a closed magnetic path of the magnetic flux with respect to the main magnetic pole part. The closed magnetic path forming magnetic pole part has an edge which is bounded on the non-magnetic part. This edge is non-parallel to the main magnetic pole part.

Abstract: A magnetic head for perpendicular magnetization has a pair of first and second blocks each composed of a nonmagnetic body and a ferromagnetic yoke joined together, a thin ferromagnetic film sandwiched between the first and second blocks, a coil wound around the thin film and the yoke of the first block, and a third ferromagnetic block attached to the first block remotely from the thin film and the second block. In a playback mode, a closed magnetic path is formed through a magnetic recording medium, the thin film, the yoke of the first block, and the third block.

Abstract: A magnetic head for tape recording and/or reproducing is composed of a pair of abutting thin magnetic metal cores with front and back gaps therebetween, and a pair of magnetic oxide cores sandwiching each of the magnetic metal cores therebetween. The magnetic oxide cores include bodies of glass disposed adjacent the front gap and sandwiching each magnetic metal core to allow the front gap to be visually checked for its depth. To fabricate such a magnetic head, magnetic oxide cores are bonded to a thin magnetic metal core, and the bonded block is cut off across the magnetic metal core to form two block pieces. Each of the block pieces is provided with bodies of glass in recesses formed in a cut surface thereof. After the cut surfaces have been ground, the block pieces are bonded with the cut surfaces confronting each other while keeping the magnetic metal cores in alignment.

Abstract: An electromagnetic transducer head for a tape recording and reproducing system comprises a pair of generally U-shaped single crystalline ferrite cores having their first legs secured together and their second legs spaced from each other to form a magnetic gap in which a wafer of glossy material is provided. Each of the ferrite cores has crystal planes (211), (110) and (111). The magnetic gap is aligned to the crystal plane (111) and the second legs of the cores are shaped to provide a tape contact surface which is parallel with the crystal plane (211). The crystal plane (110) is at right angles to the planes (211) and (111) and forms a passage for magnetic flux. The crystallographic axis <110> of each core extends at an angle to the magnetic gap so as to meet the axis <110> of the other core at a point aligned with the tape contact face.

Abstract: A ferrite core magnetic head useful in a video tape recorder is reinforced in regions near its magnetic gap by the application of a filling material which is a mixture of a glass composition such as a lead glass and a powdered electrically conducting and nonmagnetic material such as a conducting metal oxide or a metal. In thermal expansion coefficient, the glass for the filling material must be comparable to the core material of the head. The use of this filling material precludes cracking of the core by heat treatments during fabrication and deposition of dust on the head surface during operation.