EP0514976A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Combined read/write magnetic head
Assignee: Koninklijke Philips NV
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Filing: 1992-05-12
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Granted: —
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Expires: 2012-05-12
Abstract
Abstract A head (210) is disclosed in which the read head includes a magnetoresistive element (MRE) (250) overlying a substrate (220) of substantially magnetically impermeable material, a broken (discontinuous) flux guide (280 a, b) overlying the MRE and a continuous flux guide (320) overlying the broken flux guide. The write head of the combined read/write magnetic head overlies the read head and shares the continuous flux guide with the read head, the continuous flux guide serving as a bottom pole of the write head. Significantly, the dimensions of the various elements of the combined read/write magnetic head are chosen so that relatively little magnetic flux produced by the write head during writing, or entering the write head during reading, is communicated via the shared flux guide to the MRE.
Inventors
- 👤 Terry Mitchell
- 👤 William Wood
- 👤 Paul Michalek
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 05:47
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/33; G11B5/39; G11B5/3903; G11B5/3906; G11B5/3916; G11B5/3919; G11B5/3922; G11B5/3925; G11B5/3103; G11B5/3109; G11B5/3113; G11B5/3967
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
238 words
A read/write magnetic head, comprising: a substrate of substantially magnetically impermeable material; a magnetic read head overlying said substrate, said magnetic read head including a combination of a first flux guide of magnetically permeable material, an overlying second flux guide of magnetically permeable material and a first region of substantially magnetically impermeable material positioned between said first and second flux guides, said first region of material defining a read gap between said first and second flux guides at one end of said read/write magnetic head; a magnetic write head overlying said magnetic read head, said magnetic write head including a combination of a first pole, an overlying second pole of magnetically permeable material and a second region of substantially magnetically impermeable material positioned between said first and second poles, said second region of material defining a write gap between said first and second poles at said one end of said read/write magnetic head, characterized in that said read/write magnetic head further comprises a substantially single-domain magnetoresistive element (MRE) positioned between said first flux guide and said substrate, said first flux guide being a broken flux guide which includes two flux guides sections, each of which partially overlaps said MRE, said MRE, flux guides, poles and regions having thickness dimensions, and the MRE having an amount of overlap with each of said flux guide sections, so as to prevent destabilization of said MRE when writing with said write head.
Claim 2
Dependent Claim
32 words
A magnetic head as claimed in claim 1, characterized in that a flux density at said MRE during writing is equal to or less than about 10,000 gauss, whereby destabilization is prevented.
Claim 3
Dependent Claim
23 words
A magnetic head as claimed in claim 2, characterized in that said flux density is equal to or less than about 6,000 gauss.
Claim 4
Dependent Claim
23 words
A magnetic head as claimed in claim 1, characterized in that the first pole of the write head includes the second flux guide.
Claim 5
Dependent Claim
33 words
A magnetic head as claimed in claim 1, characterized in that at least a portion of said substantially magnetically impermeable material of said substrate is electrically insulating and said MRE overlies said portion.
Claim 6
Dependent Claim
18 words
A magnetic head as claimed in claim 1, characterized in that said MRE is a barber pole MRE.
Claim 7
Dependent Claim
36 words
A magnetic head as claimed in claim 1, further comprising an electrical conductor positioned between said first and second flux guides and capable of magnetic communication with said MRE via said first and second flux guides.
Claim 8
Dependent Claim
20 words
A magnetic head as claimed in claim 1, further comprising an electrical conductor positioned between said first and second poles.
Claim 9
Dependent Claim
43 words
A magnetic head as claimed in claim 8, further comprising a third region of substantially magnetically impermeable material, having a substantially planar upper surface, positioned between said first and second poles and overlying said second region, said electrical conductor overlying said supper surface.
Claim 10
Dependent Claim
23 words
A magnetic head as claimed in claim 1 in which the MRE thickness is in the range of about 0.025 to 0.080 µms.
Claim 11
Dependent Claim
27 words
A magnetic head as claimed in claim 1 in which the thickness of the broken flux guide is in the range of about 0.20 to 3.0 µms.
Claim 12
Dependent Claim
31 words
A magnetic head as claimed in claim 1 in which the overlap between the MRE and the broken flux guide sections is in the range of about 2.0 to 8.0 µms.
Claim 13
Dependent Claim
34 words
A magnetic head as claimed in claim 1 in which the thickness of the continuous flux guide, the first pole and the second pole are in the range of about 2.0 and 4.0 µms.
Claim 14
Dependent Claim
26 words
A magnetic head as claimed in claim 1 in which the thickness of the read gap is in the range of about 0.2 to 0.9 µms.
Claim 15
Dependent Claim
26 words
A magnetic head as claimed in claim 1 in which the thickness of the write gap is in the range of about 0.4 to 1.6 µms.
Claim 16
Dependent Claim
253 words
A read/write magnetic head, comprising: a substrate of substantially magnetically impermeable material; a magnetic read head overlying said substrate, said magnetic read head including a combination of a first flux guide of magnetically permeable material, an overlying second flux guide of magnetically permeable material and a first region of substantially magnetically impermeable material positioned between said first and second flux guides, said first region of material defining a read gap between said first and second flux guides at one end of said read/write magnetic head; a magnetic write head overlying said magnetic read head, said magnetic write head including a combination of a first pole, an overlying second pole of magnetically permeable material and a second region of substantially magnetically impermeable material positioned between said first and second poles, said second region of material defining a write gap between said first and second poles at said one end of said read/write magnetic head, characterized in that said read/write magnetic head further comprises a magnetoresistive element (MRE) positioned between said first flux guide and said substrate, said first flux guide being a broken flux guide which includes two flux guide sections, each of which partially overlaps said MRE, said MRE, flux guides, poles and regions having thickness dimensions, and the MRE having an amount of overlap with each of said flux guide sections, so that when reading with said read head, flux communicated to said MRE via said write head results in about 10 percent or less of the signal output of said MRE.
Claim 17
Dependent Claim
49 words
A magnetic head as claimed in claim 16, characterized in that said dimensions and said overlap are chosen so that when reading with said read head, flux communicated to said MRE via said write head results in about 5 percent or less of the signal output of said MRE.
Claim 18
Dependent Claim
23 words
A magnetic head as claimed in claim 16, characterized in that the first pole of the write head includes the second flux guide.
Claim 19
Dependent Claim
33 words
A magnetic head as claimed in claim 16, characterized in that at least a portion of said substantially magnetically impermeable material of said substrate is electrically insulating and said MRE overlies said portion.
Claim 20
Dependent Claim
18 words
A magnetic head as claimed in claim 16, characterized in that said MRE is a barber pole MRE.
Claim 21
Dependent Claim
36 words
A magnetic head as claimed in claim 16, further comprising an electrical conductor positioned between said first and second flux guides and capable of magnetic communication with said MRE via said first and second flux guides.
Claim 22
Dependent Claim
20 words
A magnetic head as claimed in claim 16, further comprising an electrical conductor positioned between said first and second poles.
Claim 23
Dependent Claim
43 words
A magnetic head as claimed in claim 22, further comprising a third region of substantially magnetically impermeable material, having a substantially planar upper surface, positioned between said first and second poles and overlying said second region, said electrical conductor overlying said upper surface.
Claim 24
Dependent Claim
23 words
A magnetic head as claimed in claim 16 in which the MRE thickness is in the range of about 0.025 to 0.080 µms.
Claim 25
Dependent Claim
27 words
A magnetic head as claimed in claim 16 in which the thickness of the broken flux guide is in the range of about 0.20 to 3.0 µms.
Claim 26
Dependent Claim
31 words
A magnetic head as claimed in claim 16 in which the overlap between the MRE and the broken flux guide sections is in the range of about 2.0 to 8.0 µms.
Claim 27
Dependent Claim
34 words
A magnetic head as claimed in claim 16 in which the thickness of the continuous flux guide, the first pole and the second pole are in the range of about 2.0 to 4.0 µms.
Claim 28
Dependent Claim
26 words
A magnetic head as claimed in claim 16 in which the thickness of the read gap is in the range of about 0.2 to 0.9 µms.
Claim 29
Dependent Claim
26 words
A magnetic head as claimed in claim 16 in which the thickness of the write gap is in the range of about 0.4 to 1.6 µms.
References Cited (Backward Citations)
No citation records indexed.
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