US4819113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic transducer head with inclined magnetic gap
Assignee: Sony Corp
•
Filing: 1985-03-19
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Granted: 1989-04-04
•
Expires: 2005-03-19
Abstract
Abstract A magnetic transducer head in which the magnetic core elements of ferromagnetic oxides are sliced obliquely across the junction surface of the core elements, ferromagnetic metal thin films are formed on the resulting inclined surfaces by employing a physical vapor deposition, and the core elements are placed with the respective ferromagnetic metal thin films abutting to each other for defining a magnetic gap therebetween, wherein the improvement consists in that said inclined surfaces with the ferromagnetic metal thin films formed thereon are inclined at a preset angle with the magnetic gap forming surface, in that non-magnetic films having high-hardness are interposed between the ferromagnetic oxide and the ferromagnetic metal thin films, and in that said ferromagnetic metal thin films and the oxide glass fillers are provided on the tape abutment surface by the intermediary of the non-magnetic film having high-hardness. The provision of the non-magnetic film having high-hardness between the ferromagnetic oxide and the ferromagnetic metal thin film is effective to inhibit the reaction otherwise occurring between the oxide and the films, while positively preventing the formation of the boundary layer with inferior magnetic properties. Likewise, the provision of the non-magnetic film having high-hardness between the ferromagnetic metal thin film and the oxide glass is effective to prevent the erosion of the film by the molten glass, while also improving the molten glass fluidity. It should be noted that the non-magnetic films having high-hardness may be provided on the interface only between the core elements and the metal thin films or on the interface only between the metal thin films and the oxide glass.
Inventors
- 👤 Makoto Kubota
- 👤 Tatsuo Kumura
- 👤 Junichi Saito
- 👤 Tomio Kobayashi
- 👤 Heikichi Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:03
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/1875; G11B5/1877; G11B5/1878
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
432 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic ferrite block and said magnetic metal thin film, each of said first and second core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap.
Claim 2
Dependent Claim
432 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic ferrite block and said magnetic metal thin film, each of said first and second core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap.
Claim 3
Dependent Claim
433 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: as first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, each of said core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic metal thin film and said non-magnetic material filling in said first notch.
Claim 4
Dependent Claim
433 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: as first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, each of said core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic metal thin film and said non-magnetic material filling in said first notch.
Claim 5
Dependent Claim
449 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic ferrite block and said metal thin film, each of said core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap, and a non-magnetic thin film interposed between said magnetic metal thin film and said non-magnetic material filling in said first notch.
Claim 6
Dependent Claim
449 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first magnetic core element, and a second magnetic core element, each of said first and second core elements comprising a magnetic ferrite block, a magnetic metal thin film integrated with said magnetic ferrite block, and a non-magnetic thin film having a hardness greater than the hardness of said magnetic film, interposed between said magnetic ferrite block and said metal thin film, each of said core elements having a first planar surface and a second planar surface portion adjacent to said first planar surface, said magnetic metal thin film on said first core element being provided on said second planar surface portion of said first core element and facing an edge thereof to said first planar surface of said first core element, said second planar surface portion of said first core element being slanted with respect to said first planar surface of said first core element, said magnetic metal thin film on said second core element being provided on said second planar surface portion of said second core element and facing an edge thereof to said first planar surface of said second core element, said second planar surface portion of said second core element being slanted with respect to said first planar surface of said second core element, said first and second core elements being bonded together along a bonding plane parallel to their said first surfaces, in such manner that an operating magnetic gap is formed between said edge of said magnetic metal thin film on said first core element and said edge of said magnetic metal thin film on said second core element, said track extending across said magnetic gap in a direction transverse to said bonding plane, said magnetic metal thin film on said first core element and said magnetic thin film on said second core element are in one common plane and forming a track width of said operating magnetic gap larger than the thickness of said magnetic metal thin film, and a common contact surface facing a travelling magnetic recording medium is formed by said first and second core elements, said metal thin film on said first core element defining a first notch with said first planar surface of said second core element, and said metal thin film on said second core element defining a second notch with said first planar surface of said first core element, said first and second notches being filled with non-magnetic material and defining the width of said operating magnetic gap, and a non-magnetic thin film interposed between said magnetic metal thin film and said non-magnetic material filling in said first notch.
Claim 7
Dependent Claim
21 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said operating magnetic gap is provided at the central
Claim 8
Dependent Claim
34 words
A magnetic transducer head according to claims 1, 2 or 3, wherein an angle between said first planar surface and said second surface as viewed from said contact surface is between 20°, and 80°.
Claim 9
Dependent Claim
49 words
A magnetic transducer head according to claims 1, 2 or 3,, further comprises an opening for winding coil provided on at least one of said core elements facing to said first planar surface, dividing said operating magnetic gap and a back gap, and a coil wound through said opening.
Claim 10
Dependent Claim
22 words
A magnetic transducer head according to claim 6, wherein said magnetic metal thin film is provided to extend to said back gap.
Claim 11
Dependent Claim
24 words
A magnetic transducer head according to claim 6, wherein said back gap is formed between each of said ferrite blocks of said core element.
Claim 12
Dependent Claim
29 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film has substantially uniform columnar structure over entire area of said magnetic metal
Claim 13
Dependent Claim
20 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film is crystalline alloy.
Claim 14
Dependent Claim
24 words
A magnetic transducer head according to claims 1, 2 or 3, therein said magnetic metal thin film is Fe - Al - Si alloys.
Claim 15
Dependent Claim
33 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film has substantially uniform characteristics of magnetic anisotropy over entire area of said magnetic metal thin film.
Claim 16
Dependent Claim
20 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film is amorphous alloy.
Claim 17
Dependent Claim
21 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film is metal-metalloid amorphous alloys.
Claim 18
Dependent Claim
21 words
A magnetic transducer head according to claims 1, 2 or 3, wherein said magnetic metal thin film is metal-metal amorphous alloys.
Claim 19
Dependent Claim
23 words
A magnetic transducer head according to claims 1 to 15, wherein a thickness of said non-magnetic film between 50 Å and 2000 Å.
Claim 20
Dependent Claim
23 words
A magnetic transducer head according to claims 1 or 6, wherein said non-magnetic film is non-magnetic oxide or non-magnetic metal or alloy thereof.
Claim 21
Dependent Claim
45 words
A magnetic transducer head according to claim 17, wherein said non-magnetic oxide is selected from the group consisting of SiO 2 , TiO 2 , Ta 2 O 5 , Al 2 O 3 , Cr 2 O 3 , glass having high melting point.
Claim 22
Dependent Claim
25 words
A magnetic transducer head according to claim 17, wherein said non-magnetic metal or alloy thereof is selected from the group consisting of Cr, Ti, Si.
Claim 23
Dependent Claim
269 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first and second magnetic core element bonded together having an operating magnetic gap between first planar surfaces of each of said magnetic core elements, and a contact surface for a travelling magnetic recording medium, said track extending across said magnetic gap in a direction transverse to the bonding surface between said first and second magnetic core elements; each of aid magnetic core elements having a third surface extending adjacent to said first planar surface and contact surface; said core element comprising a magnetic ferrite block having a second planar surface extending from said first planar surface to a side of said third surface; a magnetic metal thin film formed of said second planar surface extending from said first planar surface to said side of said third surface along a line not perpendicular to said magnetic gap as viewed on said contact surface; a non-magnetic material portion extending to said first planar surface, said contact surface and said third surface; and a non-magnetic film having a hardness greater than the hardness of said magnetic thin film, interposed between said magnetic metal thin film and said non-magnetic material portion; said first and second core elements being bonded together in such manner that an operating magnetic gap is formed between said edges of said magnetic metal thin film appearing on said first planar surface of each said core elements, and said line of said first core element and said second core element exist on a common straight line as viewed on said contact surface.
Claim 24
Dependent Claim
269 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first and second magnetic core element bonded together having an operating magnetic gap between first planar surfaces of each of said magnetic core elements, and a contact surface for a travelling magnetic recording medium, said track extending across said magnetic gap in a direction transverse to the bonding surface between said first and second magnetic core elements; each of aid magnetic core elements having a third surface extending adjacent to said first planar surface and contact surface; said core element comprising a magnetic ferrite block having a second planar surface extending from said first planar surface to a side of said third surface; a magnetic metal thin film formed of said second planar surface extending from said first planar surface to said side of said third surface along a line not perpendicular to said magnetic gap as viewed on said contact surface; a non-magnetic material portion extending to said first planar surface, said contact surface and said third surface; and a non-magnetic film having a hardness greater than the hardness of said magnetic thin film, interposed between said magnetic metal thin film and said non-magnetic material portion; said first and second core elements being bonded together in such manner that an operating magnetic gap is formed between said edges of said magnetic metal thin film appearing on said first planar surface of each said core elements, and said line of said first core element and said second core element exist on a common straight line as viewed on said contact surface.
Claim 25
Dependent Claim
23 words
A magnetic transducer head according to claim 20, wherein said operating magnetic gap is provided at the central portion of said contact surface.
Claim 26
Dependent Claim
32 words
A magnetic transducer head according to claim 20, wherein an angle between said first, planar surface and said second planar surface as viewed from said contact surface is between 20° and 80°.
Claim 27
Dependent Claim
46 words
A magnetic transducer head according to claim 20, further comprises an opening for winding coil provided on at least one of said core elements facing to said first planar surface, dividing said operating magnetic gap and a back gap, and a coil wound through said opening.
Claim 28
Dependent Claim
22 words
A magnetic transducer head according to claim 23, wherein said magnetic metal thin film is provided to extend to said back gap.
Claim 29
Dependent Claim
24 words
A magnetic transducer head according to claim 23, wherein said back gap is formed between each of said ferrite blocks of said core element.
Claim 30
Dependent Claim
28 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film has substantially uniform columnar structure over entire area of said magnetic metal thin film.
Claim 31
Dependent Claim
17 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film is crystalline alloy.
Claim 32
Dependent Claim
21 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film is Fe - Al - Si alloys.
Claim 33
Dependent Claim
30 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film has substantially uniform characteristics of magnetic anisotropy over entire area of said magnetic metal thin film.
Claim 34
Dependent Claim
17 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film is amorphous alloy.
Claim 35
Dependent Claim
18 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film is metal-metalloid amorphous alloys.
Claim 36
Dependent Claim
18 words
A magnetic transducer head according to claim 20, wherein said magnetic metal thin film is metal-metal amorphous alloys.
Claim 37
Dependent Claim
32 words
A magnetic transducer head according to claims 20 to 32, wherein said non-magnetic film is non-magnetic oxide or non-magnetic metal or alloy thereof or metal having high melting point or oxide thereof.
Claim 38
Dependent Claim
45 words
A magnetic transducer head according to claim 33, wherein said non-magnetic oxide is selected from the group consisting of SiO 2 , TiO 2 , Ta 2 O 5 , Al 2 O 3 , Cr 2 O 3 , glass having high melting point.
Claim 39
Dependent Claim
25 words
A magnetic transducer head according to claim 33, wherein said non-magnetic metal or alloy thereof is selected from the group consisting of Cr, Ti, Si.
Claim 40
Dependent Claim
28 words
A magnetic transducer head according to claim 33, wherein said metal having high melting point or oxide thereof is selected from the group consisting of W, Mo, Ta.
Claim 41
Dependent Claim
298 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first and second magnetic core element bonded together having an operating magnetic gap between first planar surfaces of each of said magnetic core elements, and a contact surface for a travelling magnetic recording medium, said track extending across said magnetic gap in a direction transverse to the bonding surface between said first and second magnetic core elements; each of said magnetic core elements having a third surface extending adjacent to said first planar surface and contact surface; said core element comprising a magnetic ferrite block having a second planar surface extending from said first planar surface to a side of said third surface; a magnetic metal thin film formed of said second planar surface extending from said first planar surface to said side of said third surface along a line not perpendicular to said magnetic gap as viewed on said contact surface; a non-magnetic material portion extending to said first planar surface, said contact surface and said third surface; a first non-magnetic film having a hardness greater than the hardness of said magnetic thin film interposed between said magnetic ferrite block and said magnetic metal thin film; and a second non-magnetic film having a hardness greater than the hardness of said magnetic thin film interposed between said magnetic metal thin film and said non-magnetic material portion; said first and second core elements being bonded together in such manner that an operating magnetic gap is formed between said edges of said magnetic metal thin film appearing on said first planar surface of each said core elements, and said line of said first core element and said second core element exist on a common straight line as viewed on said contact surface.
Claim 42
Dependent Claim
298 words
A magnetic transducer head for cooperating with a recording or reproducing track on a magnetic medium comprising: a first and second magnetic core element bonded together having an operating magnetic gap between first planar surfaces of each of said magnetic core elements, and a contact surface for a travelling magnetic recording medium, said track extending across said magnetic gap in a direction transverse to the bonding surface between said first and second magnetic core elements; each of said magnetic core elements having a third surface extending adjacent to said first planar surface and contact surface; said core element comprising a magnetic ferrite block having a second planar surface extending from said first planar surface to a side of said third surface; a magnetic metal thin film formed of said second planar surface extending from said first planar surface to said side of said third surface along a line not perpendicular to said magnetic gap as viewed on said contact surface; a non-magnetic material portion extending to said first planar surface, said contact surface and said third surface; a first non-magnetic film having a hardness greater than the hardness of said magnetic thin film interposed between said magnetic ferrite block and said magnetic metal thin film; and a second non-magnetic film having a hardness greater than the hardness of said magnetic thin film interposed between said magnetic metal thin film and said non-magnetic material portion; said first and second core elements being bonded together in such manner that an operating magnetic gap is formed between said edges of said magnetic metal thin film appearing on said first planar surface of each said core elements, and said line of said first core element and said second core element exist on a common straight line as viewed on said contact surface.
Claim 43
Dependent Claim
23 words
A magnetic transducer head according to claim 37, wherein said operating magnetic gap is provided at the central portion of said contact surface.
Claim 44
Dependent Claim
31 words
A magnetic transducer head according to claim 37, wherein an angle between said first planar surface and said second planar surface as viewed from contact surface is between 20° and 80°.
Claim 45
Dependent Claim
46 words
A magnetic transducer head according to claim 37, further comprises an opening for winding coil provided on at least one of said core elements facing to said first planar surface, dividing said operating magnetic gap and a back gap, and a coil wound through said opening.
Claim 46
Dependent Claim
22 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is provided to extend to said back gap.
Claim 47
Dependent Claim
24 words
A magnetic transducer head according to claim 37, wherein said back gap is formed between each of said ferrite blocks of said core element.
Claim 48
Dependent Claim
28 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film has substantially uniform columnar structure over entire area of said magnetic metal thin film.
Claim 49
Dependent Claim
17 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is crystalline alloy.
Claim 50
Dependent Claim
21 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is Fe - Al - Si alloys.
Claim 51
Dependent Claim
30 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film has substantially uniform characteristics of magnetic anisotropy over entire area of said magnetic metal thin film.
Claim 52
Dependent Claim
17 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is amorphous alloy.
Claim 53
Dependent Claim
18 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is metal-metalloid amorphous alloys.
Claim 54
Dependent Claim
18 words
A magnetic transducer head according to claim 37, wherein said magnetic metal thin film is metal-metal amorphous alloys.
Claim 55
Dependent Claim
25 words
A magnetic transducer head according to claim 37 to 49, wherein a thickness of said first non-magnetic film is between 50 Å and 2000 Å.
Claim 56
Dependent Claim
24 words
A magnetic transducer head according to claims 37 to 49, wherein said first non-magnetic film is non-magnetic oxide or non-magnetic metal or alloy thereof.
Claim 57
Dependent Claim
45 words
A magnetic transducer head according to claim 51, wherein said non-magnetic oxide is selected from the group consisting of SiO 2 , TiO 2 , Ta 2 O 5 , Al 2 O 3 , Cr 2 O 3 , glass having high melting point.
Claim 58
Dependent Claim
25 words
A magnetic transducer head according to claim 51, wherein said non-magnetic metal of alloy thereof is selected from the group consisting of Cr, Ti, Si.
Claim 59
Dependent Claim
33 words
A magnetic transducer head according to claim 37 to 49, wherein said second non-magnetic film is non-magnetic oxide or non-magnetic metal or alloy thereof or metal having high melting point of oxide thereof.
Claim 60
Dependent Claim
45 words
A magnetic transducer head according to claim 54, wherein said non-magnetic oxide is selected from the group consisting of SiO 2 , TiO 2 , Ta 2 O 5 , Al 2 O 3 , Cr 2 O 3 , glass having high melting point.
Claim 61
Dependent Claim
25 words
A magnetic transducer head according to claim 54, wherein said non-magnetic metal or alloy thereof is selected from the group consisting of Cr, T, Si.
Claim 62
Dependent Claim
28 words
A magnetic transducer head according to claim 54, wherein said metal having high melting point or oxide thereof is selected from the group consisting of W, Mo, Ta.
Claim 63
Dependent Claim
39 words
A magnetic transducer head according to claims 20 or 37, further comprises cut out portions formed on each of said core elements extending to said first planar surface, said contact surface and a surface opposite to said third surface.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-03 | 1992-10-03 | 1993-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-03 | 1996-10-03 | 1997-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-03 | 2000-10-03 | 2001-04-04 | $7700.00 | Window Closed / Lapsed |