Abstract: An armature, a method for producing the armature and a mold for molding the same are so configured that the coil pitch of each of phase coils is set to a value of 125% or less of the pole pitch, the gap between the respective phase coils of any one of layers is so disposed as to face the intenral space of each of the phase coils of the other layer being contact with that layer, and the registering face of the mold for molding the periphery of the armature is so formed as to be parallel with the axial direciton of the armature.

Abstract: A mold for forming coreless armatures having an upper mold and a lower mold. The lower mold has a mold cavity for receiving a shaft capable of supporting windings of a coreless armature. An elastic ring plate is placed between the upper and lower molds and is adapted for being compressed therebetween. The elastic ring plate is further adapted to contact terminal ends of the windings as they extend outside of the mold cavity, and to seal said mold cavity with the terminal ends extending therefrom.

Abstract: An armature, a method for producing the armature and a mold for molding the same are so configured that the coil pitch of each of phase coils is set to a value of 125% or less of the pole pitch, the gap between the respective phase coils of any one of layers is so disposed as to face the intenral space of each of the phase coils of the other layer being contact with that layer, and the registering face of the mold for molding the periphery of the armature is so formed as to be parallel with the axial direction of the armature.

Abstract: A magnetic recording medium has a base film, an under coating layer formed on the base film, and two magnetic films formed on the under coating layer. An intermediate layer having little stiffness is interposed between the magnetic films to separate them.

Abstract: A magnetic recording medium having a base, a first magnetic layer formed on the base, and a second magnetic layer formed on the first magnetic layer. The magnetic recording medium further comprises a third magnetic layer which does not contain a binder formed on the second magnetic layer. A third magnetic layer containing a binder has a predetermined thickness to cover surface roughness of the second magnetic layer and functions as a protection layer for the second magnetic layer.

Abstract: A magnetic head characterized by comprising:a first half including a first block made of a ferromagnetic material and a second block made of a non-magnetic material jointed to said first block, said first half being formed with a notch separating at least said second block;a ferromagnetic first thin film formed on a surface of said first half containing one surface of each of said first and second blocks and having a bay defined by said notch;a ferromagnetic second thin film and a non-magnetic third thin film formed on said first thin film which are opposite to each other with said bay therebetween;a second half forming a core block with said first half, which is fitted to said first half so that said first, second and third thin films are sandwiched between said first and second halves, and which has at least a non-magnetic portion opposite to said second block, and which is formed with a notch opposite to said notch of said first half; anda magnetic flux detecting means provided at a magnetic path constitut

Abstract: A magnetic recording device comprises a winding and magnetic head guiding magnetic flux produced by the winding to a recording medium and magnetically recording information on said medium. The magnetic head includes a chip formed on nonmagnetic material having a narrow distal end face and a ferromagnetic thin membrane held by said chip, having one end exposed from the distal end face of said chip and the other extending on the winding side, and passing magnetic flux from said winding to said one end, whereby information is recorded on said recording medium through said one end.

Abstract: A thermomagnetic recording device for recording information on a magnetic recording medium having magnetic anisotropy across the thickness thereof comprises a laser beam irradiation mechanism applying a laser beam to said magnetic recording medium to reduce the coercive force thereof, and a single-pole magnetic head including a ferromagnetic thin membrane having an end face located opposite to said magnetic recording medium, a main body supporting said thin membrane, and a coil applying a perpendicular magnetic field to said recording medium through said end face of said thin membrane.

Abstract: A heat magnetic recording and reproducing apparatus is disclosed. The apparatus comprises a record medium running in a predetermined direction, a means for generating a laser light beam for locally heating the medium, a magnetic field generating device for generating a magnetic field at the heated portion, an information recording means provided in opposition to the magnetic field generating device and having an auxiliary magnetic pole piece for focusing a magnetic flux from the magnetic field generating device into at least the heated portion, a means provided at a front stage of the information recording means to the running of the medium for generating a laser light beam for locally heating the medium, a magnetic field generating device for generating a magnetic field at the heated portion, and an information erasing means having an auxiliary magnetic pole piece for focusing a magnetic flux from the magnetic field generating device into the heated portion.

Abstract: A method of magnetizing an erasing head for small type tape recorders is disclosed. An erasing head having its opposite ends formed in at least one convex surface is disposed in a space formed between at least two opposed electromagnetic poles. That surface of the electromagnetic pole which is opposed to the convex surface of the erasing head is made concave which corresponds in curvature to the convex surface of the erasing head such that a tangential direction of a tape travelling movement is perpendicular to a direction of a magnetic flux of the erasing head. In addition, a center axis of the erasing head is mechanically aligned with a center axis common to both the opposite electromagnetic poles by means of a jig such that a widthwise direction of a tape is perpendicular to the direction of magnetic flux of the erasing head.

Abstract: An erase head comprises a magnetizable material which can be magnetized into a permanent magnet having N- and S-poles. The magnetization takes place in a manner such that one of the poles which is the first to be contacted by a magnetic medium to be erased is magnetized to produce a field strength which is less than the magnetic field strength produced by the other pole.

Abstract: A composite magnetic head including a record/playback gap and an erase gap comprises a straight central core, a pair of arcuate lateral cores having their ends disposed in opposing relationship with the opposite ends of the central core disposed therebetween, each of the lateral cores being formed with a bobbin carrying portion at its one end which extends in a direction perpendicular to the length of the central core, a bobbin having a central flange and a pair of flanges at the opposite ends, the central flange being formed with an opening for receiving the central core and the bobbin being formed with a slot extending through the entire length of the bobbin including the flanges at the opposite ends for receiving the lateral cores, the slot extending in a direction perpendicular to the opening which receives the central core, and a pair of coils disposed between the central flange and the respective end flanges, the central core and the lateral cores forming a record/playback gap and an erase head at their

Abstract: A magnetic head comprises a pair of core pieces with a spacer interposed therebetween which defines a gap, a yoke which interconnects the ends of the both core pieces located remote from the gap, a bobbin into which the both core pieces and the yoke are fitted to maintain them joined together, and a coil wound around the bobbin. The head is manufactured by the steps of joining together a pair of core pieces with an interposed spacer which defines a gap, applying an adhesive to the mating ends of the both core pieces and the yoke, and fitting the core pieces and the yoke into the bobbin.