US4065365A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for improving frictional surface in cylinders or sleeves of internal combustion engines
Assignee: Aplicaciones Industriales de Cromoduro SA
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Filing: 1976-12-29
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Granted: 1977-12-27
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Expires: 1996-12-29
Abstract
Abstract Method of preparing chromium plated surfaces of improved anti-friction property, by machining the base material to a smooth finish, chromium plating the machined surface of the base material, heating the chromium plated surface at 150°-325° C for 1-3 hours, cooling and honing the surface, and lapping the surface with an abrasive to a surface finish such that the roughness of the surface measures 25-50 micro-inches center line average.
Inventors
- 👤 Juan Retolaza Ibarguengoitia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:33
CPC Classifications
C; C25; C25D; C25D5/00; C25D5/34; C25D5/48; C25D7/00; C25D7/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
86 words
A method for preparing a chromium plated surface which comprises machining a metal base material to a smooth finish of up to 10 micro-inches CLA, chromium plating the machined surface, heat treating the chromium plated surface at a temperature between 150° and 325° C for 1 to 3 hours, cooling the heated surface in air, honing the cooled surface to remove irregularities from said surface, and lapping or blasting the honed surface with abrasive grit to obtain a surface finish between 25 and 50 micro-inches CLA.
Claim 2
Independent Claim
86 words
A method for preparing a chromium plated surface which comprises machining a metal base material to a smooth finish of up to 10 micro-inches CLA, chromium plating the machined surface, heat treating the chromium plated surface at a temperature between 150° and 325° C for 1 to 3 hours, cooling the heated surface in air, honing the cooled surface to remove irregularities from said surface, and lapping or blasting the honed surface with abrasive grit to obtain a surface finish between 25 and 50 micro-inches CLA.
Claim 3
Dependent Claim
26 words
A method according to claim 1, wherein the chromium plated surface is a chromium plated cylinder or sleeve suitable for use in an internal combustion engine.
Claim 4
Dependent Claim
22 words
A method according to claim 2, further comprising mechanically treating the lapped or blasted surface with an abrasive to polish said surface.
Claim 5
Dependent Claim
72 words
A method according to claim 3, wherein the mechanical treatment is carried out by means of an expanding mandrel in which the parts of the mandrel that come into contact with the lapped or blasted surface are interspaced with an abrasive mixed with an elastic carrier, the lapped or blasted surface is lubricated during said mechanical treatment, and the mandrel is simultaneously rotated about its axis and subjectd to a reciprocating movement.
Claim 6
Dependent Claim
63 words
A method according to claim 4, wherein the parts of the mandrel that come into contact with the lapped or blasted surface are under a pressure of 10 to 60 p.s.i., the rotation of the mandrel is at a rate of 30 to 100 r.p.m. and the reciprocating movement of the mandrel is at a rate of 40 to 60 strokes per minute.
Claim 7
Dependent Claim
51 words
A method according to claim 2, further comprising chemically treating a portion of the honed surface, prior to lapping or blasting, with hydrochloric acid having a concentration of 10 to 30%, thus providing said treated portion with a greater porosity than the untreated portion after carrying out the lapping or blasting.
Claim 8
Dependent Claim
77 words
A method according to claim 2, further comprising electrochemically treating a portion of the honed surface, prior to lapping or blasting, by subjecting said portion to cathodic or anodic attack in an electrolyte selected from the group consisting of oxalic acid, sulfuric acid, chromic acid and an alkaline hydroxide, the concentration of said electrolyte being 10 to 30%, thus providing said treated portion with a greater porosity than the untreated portion after carrying out lapping or blasting.
Claim 9
Dependent Claim
30 words
A method according to claim 7, wherein the electrochemical treatment is carried out at a current intensity of 10 to 15 amperes per sq. cm. for 1 to 15 minutes.
Claim 10
Dependent Claim
16 words
A method according to claim 2, wherein the abrasive grit is silicon carbide or aluminum oxide.
Claim 11
Dependent Claim
17 words
A method according to claim 1, wherein the metal base material is iron, steel, aluminum or copper.
References Cited (Backward Citations)
US2430750A
Cited
US2450296A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |