Source: http://www.google.com/patents/US6362940?dq=5,664,133
Timestamp: 2017-10-23 07:23:54
Document Index: 756687802

Matched Legal Cases: ['art 45', 'art 45', 'art 45', 'art 45', 'art 45', 'art 45', 'art 45', 'art 45', 'art 45']

Patent US6362940 - Recording-reproducing magnetic head - Google Patents
A recording-reproducing magnetic head comprising a magnetoresistance effect reproducing head and an inductive recording head. The magnetoresistance effect reproducing head having a magnetoresistance effect element and the inductive recording head having a lower magnetic core, an upper magnetic core,...http://www.google.com/patents/US6362940?utm_source=gb-gplus-sharePatent US6362940 - Recording-reproducing magnetic head
Publication number US6362940 B1
Application number US 09/520,633
Also published as US5633771, US6056996, US6115216
Publication number 09520633, 520633, US 6362940 B1, US 6362940B1, US-B1-6362940, US6362940 B1, US6362940B1
Inventors Hiroaki Yoda, Atsuhito Sawabe, Hitoshi Iwasaki, Naoyuki Inoue, Akio Hori
Patent Citations (17), Referenced by (5), Classifications (18), Legal Events (4)
Recording-reproducing magnetic head
US 6362940 B1
1. A recording-reproducing magnetic head comprising a magnetoresistance effect reproducing head and an inductive recording head;
said magnetoresistance effect reproducing head including a magnetoresistance effect element;
said inductive recording head including a lower magnetic core, an upper magnetic core, coils sandwiched between said lower and upper magnetic cores at mid-parts thereof, and a recording magnetic gap layer sandwiched between said lower and upper magnetic cores at leading end parts thereof;
said leading end parts of said lower and upper magnetic cores having a protruding part protruding to said recording magnetic gap layer;
wherein said leading end part of said lower magnetic core further has a second protruding part protruding toward said magnetoresistance effect element;
said upper magnetic core having a continuous magnetic body which extends from said protruding part to said mid-part; and
a center line of said protruding part of said lower magnetic core, which extends in a track length direction on a surface opposite a medium, intersecting said protruding part of said upper magnetic core.
2. The recording-reproducing magnetic head according to claim 1, wherein said magnetoresistance effect reproducing head further includes a lower shield layer, a lower magnetic gap-forming layer between said lower shield layer and said magnetoresistance effect element, an upper magnetic gap-forming layer on said magnetoresistance effect element and an upper shield layer on said upper magnetic gap-forming layer;
said second protruding part protruding so as to contact said upper magnetic gap-forming layer.
3. A recording-reproducing magnetic head comprising a magnetoresistance effect reproducing head and an inductive recording head;
said magnetoresistance effect reproducing head including a lower shield layer, a lower magnetic gap-forming layer provided on said lower shield layer, a magnetoresistance effect element provided on said lower magnetic gap-forming layer, an upper magnetic gap-forming layer provided on said magnetoresistance effect element and an upper shield layer provided on said upper magnetic gap-forming layer;
said upper shield layer having a protruding part protruding so as to contact said upper magnetic gap-forming layer;
said leading end parts of said lower and upper magnetic cores having a protruding part protruding to said recording magnetic gap layer; and
a center line of said protruding part of said lower magnetic core, which extends in a track length direction on a surface opposite a medium, intersecting said protruding part of said upper magnetic core and said protruding part of said upper shield layer.
4. The recording-reproducing magnetic head according to claim 3, wherein said protruding parts of said lower and upper magnetic cores have converging cross sections such that a width of each of the cross sections in a track width direction decreases toward said recording magnetic gap layer.
wherein said protruding parts of said lower and upper magnetic cores have converging cross sections such that a width of each of the cross sections in a track width direction decreases toward said recording magnetic gap layer;
FIGS. 5a-5 b show the steps of a process for the production of the separate recording-reproducing type magnetic head shown in FIG. 1, subsequent to the part of the process shown in FIG. 4e.
FIG. 6 is a cross section showing an example of modification of the separate recording-reproducing type magnetic head shown in FIG. 1.
FIGS. 25a-25 b show part of the steps of a process for process for the production of the MR head shown in FIG. 23, subsequent to the part of the process shown in FIG. 24c.
FIG. 26 is a cross section showing the construction of a separate recording-reproducing type magnetic head using the MR head shown in FIG. 23.
The first magnetic film 45 on the lower side in the MR film (spin valve film) 44 is furnished with a protruding part 45 a extended in the direction of the surface opposite a medium. It is recessed from the surface opposite the medium except for the protruding part 45 a. In other words, only the leading end surface of the protruding part 45 a forms the surface opposite the medium. The nonmagnetic film 46 and the second magnetic film 47 are formed as superposed on the part of the first magnetic layer 45 except for the protruding part 45 a. They are recessed from the surface opposite the medium similarly to the part of the first magnetic layer 45 except for the protruding part 45 a.
A pair of leads 48 are severally formed on the second magnetic film 47 which is recessed from the surface opposite the medium. These components jointly form a MR element 49. Thus, the protruding part 45 a of the first magnetic film 45 exclusively responds to an external magnetic field (signal magnetic field) because the MR element 49 is recessed from the surface opposite the medium except for the protruding part 45 a of the first magnetic film 45. As a result, the protruding part 45 a of the first magnetic film 45 constitutes a magnetic field responding part and the width Tr of the magnetic field responding part forms the width of the protruding part 45 a.
On the MR element 49, an upper regenerating magnetic gap layer 50 and insulating layers 51 for securing dielectric strength between the lead 48 and an upper shield layer 52 are formed. The insulating layers 51, similarly to the various embodiments described above, are so formed as to cover the upper surface of the lead 48. The upper shield layer 52 is formed as partly embedded in a trench 51 a which is formed in the insulating layers 51. These components jointly form a shield type MR head 53 which functions as a regenerating head.
US5315469 Jul 25, 1991 May 24, 1994 Applied Magnetics Corporation Magnetic recording head which produces variable erase bands
US5422571 Feb 8, 1993 Jun 6, 1995 International Business Machines Corporation Magnetoresistive spin valve sensor having a nonmagnetic back layer
US5872693 Mar 24, 1997 Feb 16, 1999 Kabushiki Kaisha Toshiba Thin-film magnetic head having a portion of the upper magnetic core coplanar with a portion of the lower magnetic core
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JPH03205607A Title not available
JPH03296907A Title not available
JPS554727A Title not available
JPS61248212A Title not available
US6751846 Mar 31, 2003 Jun 22, 2004 Kabushiki Kaisha Toshiba Magnetic head manufacturing method
US6982932 * Sep 10, 2003 Jan 3, 2006 Matsushita Electric Industrial Co., Ltd. Recording/reproducing head and recording/reproducing apparatus incorporating the same
US7262940 * Feb 12, 2004 Aug 28, 2007 Hitachi Global Storage Technologies Japan, Ltd. Separate read/write magnetic head
US20040228041 * Feb 12, 2004 Nov 18, 2004 Hitachi, Ltd. Separate read/write magnetic head
U.S. Classification 360/317, G9B/5.123, G9B/5.135, 360/125.64, 360/125.51
Cooperative Classification G11B5/3163, G11B2005/3996, G11B5/3116, G11B5/3967, G11B5/3929, B82Y25/00, B82Y10/00
European Classification B82Y10/00, B82Y25/00, G11B5/39C3, G11B5/39C1H