Patent US4796127A successfully refreshed from Google Patents.
US4796127A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recording head slider
Assignee: Nippon Tungsten Co Ltd
•
Filing: 1988-01-11
•
Granted: 1989-01-03
•
Expires: 2008-01-11
Abstract
Abstract A recording head slider comprises a slider body having a fluid bearing surface on a primary surface thereof and at least one transducer on at least one side of the slider body, the slider body being made of a sintered body produced by sintering a base composition consisting essentially of 10-40 percent by volume of silicon carbide and the balance being alumina. The base composition may comprise 0.2-10 percent by weight of sintering aids MgO, Y2O3, ZrO2, CaO, Er2O3 and Cr2O3. This slider has high precision machinability and compatibility with recording media.
Inventors
- 👤 Toshiaki Wada
- 👤 Mitsuhiko Furukawa
- 👤 Masaharu Shiroyama
- 👤 Michito Miyahara
- 👤 Mitsuyoshi Nagano
- 👤 Shigeki Mohri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:57
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3103; G11B5/3106; G11B5/10; G11B5/48; G11B5/58; G11B5/60; G11B5/6005
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
74 words
A recording head slider comprising a slider body having a fluid bearing surface on a primary surface thereof and at least one transducer on at least one side of the slider body, the slider body being made of a sintered body produced by sintering a base composition consisting essentially of 10-40 percent by volume of silicon carbide and the balance being alumina, whereby a sintered body having excellent wear resistance and machinability is obtained.
Claim 2
Dependent Claim
74 words
A recording head slider comprising a slider body having a fluid bearing surface on a primary surface thereof and at least one transducer on at least one side of the slider body, the slider body being made of a sintered body produced by sintering a base composition consisting essentially of 10-40 percent by volume of silicon carbide and the balance being alumina, whereby a sintered body having excellent wear resistance and machinability is obtained.
Claim 3
Dependent Claim
57 words
The recording head slider as defined in claim 1, wherein said base composition further comprises 0.2-10 percent by weight, calculated on the entire composition, of at least one of sintering aids selected from the group consisting of MgO, Y 2 O 3 , ZrO 2 , CaO, Er 2 O 3 and Cr 2 O 3 .
Claim 4
Dependent Claim
17 words
The recording head slider as defined in claim 1, wherein the transducer comprises a thin film circuit.
Claim 5
Dependent Claim
22 words
The recording head slider as defined in claim 1, wherein the fluid bearing surface comprises at least one positive pressure producing surface.
Claim 6
Dependent Claim
20 words
The recording head slider as defined in claim 1, wherein the fluid bearing surface comprises a negative pressure producing surface.
Claim 7
Dependent Claim
31 words
The recording head slider as defined in claim 4, wherein the fluid bearing surface includes a pair of positive pressure producing surfaces disposed on the marginal area of the primary source.
Claim 8
Dependent Claim
24 words
The recording head slider as defined in claim 5, wherein the negative pressure surface is disposed on the central area of the primary surface.
Claim 9
Dependent Claim
31 words
The recording head slider as defined in claim 6, wherein the fluid bearing surface further includes a negative pressure producing surface disposed between the pair of the positive pressure producing surfaces.
Claim 10
Dependent Claim
21 words
The recording head slider as defined in claim 1, wherein the base composition comprises 15-35 percent by volume of silicon carbide.
Claim 11
Dependent Claim
23 words
The recording head slider as defined in claim 2, wherein the sintering aid is at least one of MgO and ZrO 2 .
Claim 12
Dependent Claim
25 words
The recording head slider as defined in claim 1, wherein the slider body has a density of at least 98% relative to the theoretical density.
Claim 13
Dependent Claim
23 words
The recording head slider as defined in claim 11, wherein the slider body has an average crystal grain size not exceeding 2 μm.
Claim 14
Dependent Claim
23 words
The recording head slider as defined in claim 12, wherein the slider body has a thermal conductivity of at least 0.05 cal/cm.sec.° C.
Claim 15
Dependent Claim
63 words
A recording head slider substrate of a plate form having a main surface for applying a plurality of transducers on areas thereof assigned to slider bodies to be cut off from the plate, the slider substrate being made of a sintered body produced by sintering a base composition consisting essentially of 10-40 percent by volume of silicon carbide and the balance being alumina.
Claim 16
Dependent Claim
63 words
A recording head slider substrate of a plate form having a main surface for applying a plurality of transducers on areas thereof assigned to slider bodies to be cut off from the plate, the slider substrate being made of a sintered body produced by sintering a base composition consisting essentially of 10-40 percent by volume of silicon carbide and the balance being alumina.
Claim 17
Dependent Claim
58 words
The recording head slider substrate as defined in claim 14, wherein said base composition further comprises 0.2-10 percent by weight, calculated on the entire composition, of at least one of sintering aids selected from the group consisting of MgO, Y 2 O 3 , ZrO 2 , CaO, Er 2 O 3 and Cr 2 O 3 .
Claim 18
Dependent Claim
23 words
The recording head slider substrate as defined in claim 14, wherein the at least one transducer has been applied on said side surface.
Claim 19
Dependent Claim
18 words
The recording head slider substrate as defined in claim 16, wherein the transducer comprises a thin film circuit.
Claim 20
Dependent Claim
22 words
The recording head slider substrate as defined in claim 14, wherein the base composition comprises 15--35 percent by volume of silicon carbide.
Claim 21
Dependent Claim
24 words
The recording head slider substrate as defined in claim 15, wherein the sintering aid is at least one of MgO and ZrO 2 .
Claim 22
Dependent Claim
26 words
The recording head slider substrate as defined in claim 14, wherein the slider body has a density of at least 98% relative to the theoretical density.
Claim 23
Dependent Claim
24 words
The recording head slider substrate as defined in claim 20, wherein the slider substrate has an average crystal grain size not exceeding 2 μm.
Claim 24
Dependent Claim
23 words
The recording head slider substrate as defined in claim 21, wherein the slider body has a thermal conductivity at least 0.05 cal/cm.sec.° C.
References Cited (Backward Citations)
US4489484A
Cited
US4430440A
Cited
US4549238A
Cited
US4487734A
Cited
US4649448A
Cited
JPS6080185A
Cited
US4636894A
Cited
JPS61155261A
Cited
US4598052A
Cited
US4639803A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-03 | 1992-07-04 | 1993-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-03 | 1996-07-04 | 1997-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-03 | 2000-07-04 | 2001-01-03 | $7700.00 | Window Closed / Lapsed |