US4876996A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for the valve control gear of an internal combustion engine
Assignee: INA Waelzlager Schaeffler OHG
•
Filing: 1989-03-07
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Granted: 1989-10-31
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Expires: 2009-03-07
Abstract
Abstract A device for the valve control gear of an internal combustion engine including a surface of which acts as a stop face for a cam. The surface is chromium coated.
Inventors
- 👤 Ernst Mayer
- 👤 Norbert Geheeb
- 👤 Uwe Kohler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:41
CPC Classifications
F; F01; F01L; F01L1/00; F01L1/20; F01L1/22; F01L1/24; F01L1/245; F01L1/25; F01L1/12; F01L1/14; F01L1/16
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
45 words
A device for the valve control gear of an internal combustion engine a surface of which acts as a stop face for a cam, characterized in that a chromium coating is applied to the stop face, the maximum thickness of this coating being 5 μm.
Claim 2
Independent Claim
45 words
A device for the valve control gear of an internal combustion engine a surface of which acts as a stop face for a cam, characterized in that a chromium coating is applied to the stop face, the maximum thickness of this coating being 5 μm.
Claim 3
Dependent Claim
10 words
A device of claim 1 which is a cup tappet.
Claim 4
Dependent Claim
22 words
A device of claim 1 wherein the chromium coating comprises several consecutively applied layers whereby at least the last layer has micro-cracks.
Claim 5
Dependent Claim
15 words
A device of claim 3 wherein the last layer applied has at least 600 cracks/cm.
Claim 6
Dependent Claim
24 words
A device of claim 1 wherein at least the first layer, applied directly to the material of the device, is substantially free from micro-cracks.
Claim 7
Dependent Claim
13 words
A device of claim 1 wherein the maximum coating thickness is 2.5 μm.
References Cited (Backward Citations)
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US3131470A
Cited
US3545415A
Cited
US4230491A
Cited
US4367701A
Cited
USRE32167E
Cited
US4688526A
Cited
US4829950A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-30 | 1993-05-01 | 1993-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-30 | 1997-05-01 | 1997-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-30 | 2001-05-01 | 2001-10-31 | $7700.00 | Window Closed / Lapsed |