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Patent US4734802A successfully refreshed from Google Patents.
US4734802A
Expired / Lapsed
US
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Film magnetic head slider having a contacting portion containing zirconia and carbon
Assignee: Hitachi Ltd
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Filing: 1985-10-01
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Granted: 1988-03-29
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Expires: 2005-10-01
Abstract
Abstract A film magnetic slider which comprises a slider performing contact-start-stop actions on a recording medium and being provided with a film magnetic head device on the side end of the slider, at least the recording-medium-contacting part of the slider being made from a sintered material having a thermal conductivity of not more than 0.02 cal/cm.sec. DEG C. and an average crystal grain size of not more than 5 mu m has a good slidability on the recording medium and a good machinability and can improve the life of the recording medium.
Inventors
- 👤 Shinsuke Higuchi
- 👤 Yukio Takeda
- 👤 Shiro Iijima
- 👤 Masaki Ohura
- 👤 Sadanori Nagaike
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:08
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; C; C04; C04B; C04B35/00; C04B35/01; C04B35/48; C04B35/486; G11B5/10; G11B5/48; G11B5/58; G11B5/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
89 words
A film magnetic head slider which comprises a slider performing contact-start-stop actions on a recording medium and being provided with a film magnetic head device on a side end of the slider, at least the recording medium-contacting part of a slider being made from a sintered material containing ZrO 2 in the cubic system as the major component, and having an average crystal grain size of not more than 5 μm, a carbon content of 0.01 to 1% by weight, and thermal conductivity of not more than 0.02 cal/cm.sec.°C.
Claim 2
Dependent Claim
89 words
A film magnetic head slider which comprises a slider performing contact-start-stop actions on a recording medium and being provided with a film magnetic head device on a side end of the slider, at least the recording medium-contacting part of a slider being made from a sintered material containing ZrO 2 in the cubic system as the major component, and having an average crystal grain size of not more than 5 μm, a carbon content of 0.01 to 1% by weight, and thermal conductivity of not more than 0.02 cal/cm.sec.°C.
Claim 3
Dependent Claim
19 words
A film magnetic head slider according to claim 1, wherein said entire slider is made from said sintered material.
Claim 4
Dependent Claim
19 words
A film magnetic head slider according to claim 1, wherein the ZrO 2 and the carbon are thoroughly mixed.
Claim 5
Dependent Claim
17 words
A film magnetic head slider according to claim 1, wherein said sintered material further includes a stabilizer.
Claim 6
Dependent Claim
36 words
A film magnetic head slider according to claim 4, wherein said stabilizer is selected from the group consisting of Y 2 O 3 , CaO, MgO, CeO 2 , SrO and La 2 O 3 .
Claim 7
Dependent Claim
31 words
A film magnetic head slider according to claim 1, wherein the sintered material is prepared by firing a mixture of an organic material and ZrO 2 powders in a non-oxidative atmosphere.
Claim 8
Dependent Claim
31 words
A film magnetic head slider according to claim 6, wherein the organic material is 0.02 to 2% by weight of novolak phenol resin on the basis of the ZrO 2 powders.
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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) | 1991-03-29 | 1991-09-28 | 1992-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-29 | 1995-09-28 | 1996-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-29 | 1999-09-28 | 2000-03-29 | $7700.00 | Window Closed / Lapsed |