US4735128A
Expired / Lapsed
US
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Piston
Assignee: Metal Leve SA Industria e Commercio
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Filing: 1986-02-05
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Granted: 1988-04-05
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Expires: 2006-02-05
Abstract
Abstract A piston for internal combustion engines made of a light alloy and comprising a skirt portion and a head portion, having a ceramic insert adapted on the head portion and connected to same by mechanical locking. The ceramic insert is provided with pores at least on the portion engaging the piston head. The pores have a size which enable them to be filled with the light alloy during the manufacture of the piston by the squeeze casting method.
Inventors
- 👤 Duraid Mahrus
- 👤 Alexandre Afonso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:10
CPC Classifications
F; F02; F02F; F02F7/00; F02F7/0085; F02F7/0087; F02F3/00; F02F3/10; F02F3/12; F02B; F02B3/00; F02B3/06; F05; F05C; F05C2201/00; F05C2201/02; F05C2201/021; F05C2253/00; F05C2253/16; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249; Y10T29/49256; Y10T29/49261
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
215 words
A method for manufacturing an internal combustion engine piston made of a light alloy and comprising a skirt portion and a head portion on which a ceramic insert is mounted, the method comprising the steps of: obtaining a ceramic insert having an upper face and a predetermined porosity at least on its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of which the piston is made into at least part of the height of the ceramic insert, said upper portion of said ceramic insert having a second predetermined porosity which is substantially less than said first predetermined porosity; heating the ceramic insert to a temperature between about 400° to 600° C.; heating a casting die to a temperature between about 200° to 400° C.; placing the ceramic insert on the bottom of the die, the upper surface of the ceramic insert facing the bottom of the die; lowering a punch into the die and apply a progressive pressure to the punch so as to form the piston and cause the light metal to fill the pores of the ceramic insert; removing the piston from the die after solidification of the light alloy; and machining the piston to its final dimension.
Claim 2
Independent Claim
215 words
A method for manufacturing an internal combustion engine piston made of a light alloy and comprising a skirt portion and a head portion on which a ceramic insert is mounted, the method comprising the steps of: obtaining a ceramic insert having an upper face and a predetermined porosity at least on its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of which the piston is made into at least part of the height of the ceramic insert, said upper portion of said ceramic insert having a second predetermined porosity which is substantially less than said first predetermined porosity; heating the ceramic insert to a temperature between about 400° to 600° C.; heating a casting die to a temperature between about 200° to 400° C.; placing the ceramic insert on the bottom of the die, the upper surface of the ceramic insert facing the bottom of the die; lowering a punch into the die and apply a progressive pressure to the punch so as to form the piston and cause the light metal to fill the pores of the ceramic insert; removing the piston from the die after solidification of the light alloy; and machining the piston to its final dimension.
Claim 3
Dependent Claim
24 words
A method as defined in claim 1, wherein the diameters of the ceramic insert and of the piston head portion are substantially the same.
Claim 4
Dependent Claim
25 words
A method as defined in claim 2, wherein the ceramic insert is provided with at least one peripheral annular groove to accommodate a piston ring.
Claim 5
Dependent Claim
25 words
A method as defined in claim 3, wherein a ceramic layer of high heat resistance is applied to the upper face of the ceramic insert.
Claim 6
Dependent Claim
25 words
A method as defined in claim 2, wherein a ceramic layer of high heat resistance is applied to the upper face of the ceramic insert.
Claim 7
Dependent Claim
25 words
A method as defined in claim 1, wherein a ceramic layer of high heat resistance is applied to the upper face of the ceramic insert.
Claim 8
Dependent Claim
21 words
A method as defined in claim 6, wherein the ceramic layer is applied by a diffusion, plasma spraying or immersion process.
Claim 9
Dependent Claim
100 words
A piston for internal combustion engines, made of a light alloy and including a skirt portion and a head portion on which a ceramic insert is mounted, wherein said ceramic insert has a predetermined porosity at least on its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of which the piston is made into at least part of the height of the ceramic insert, said upper portion of said ceramic insert having a second predetermined porosity which is substantially less than said first predetermined porosity.
Claim 10
Dependent Claim
100 words
A piston for internal combustion engines, made of a light alloy and including a skirt portion and a head portion on which a ceramic insert is mounted, wherein said ceramic insert has a predetermined porosity at least on its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of which the piston is made into at least part of the height of the ceramic insert, said upper portion of said ceramic insert having a second predetermined porosity which is substantially less than said first predetermined porosity.
Claim 11
Dependent Claim
18 words
The piston as claimd in claim 8, wherein the top of insert is provided with a ceramic layer.
Claim 12
Dependent Claim
94 words
A piston for internal combustion engines, made of a light alloy and including a skirt portion and a head portion on which a ceramic insert is mounted, said ceramic insert having a predetermined porosity at least in its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of the piston into at least part of the height of the ceramic insert, the pores of the ceramic insert tapering from the lower portion toward the upper portion of the ceramic insert.
Claim 13
Dependent Claim
94 words
A piston for internal combustion engines, made of a light alloy and including a skirt portion and a head portion on which a ceramic insert is mounted, said ceramic insert having a predetermined porosity at least in its lower portion, said predetermined porosity being such that the pores are dimensioned to enable the penetration and subsequent solidification of the light alloy of the piston into at least part of the height of the ceramic insert, the pores of the ceramic insert tapering from the lower portion toward the upper portion of the ceramic insert.
Claim 14
Dependent Claim
33 words
The piston as claimed in claim 10, wherein the size of the pores of insert is 20 to 40 pm on the lower portion and 1 to 10 pm on the upper portion.
Claim 15
Dependent Claim
18 words
The piston as claimed in claim 11, wherein the top of insert is provided with a ceramic layer.
Claim 16
Dependent Claim
23 words
The piston is claimed in claim 10, wherein the ceramic insert has an annular configuration and is in coaxial arrangement with the piston.
Claim 17
Dependent Claim
43 words
The piston as claimed in claim 13, wherein the diameter of the ceramic insert is substantially the same as that of the head portion of piston, and the ceramic insert is provided with at least one peripheral annular groove for a piston ring.
Claim 18
Dependent Claim
27 words
The piston is claimed in claims 14, wherein the height of the peripheral portion of the ceramic insert is greater than the height of the central portion.
Claim 19
Dependent Claim
27 words
The piston as claimed in claim 15, wherein the height of the peripheral portion of the ceramic insert is greater than the height of the central portion.
Claim 20
Dependent Claim
18 words
The piston as claimed in claim 14, wherein the top of insert is provided with a ceramic layer.
Claim 21
Dependent Claim
18 words
The piston as claimed in claim 13, wherein the top of insert is provided with a ceramic layer.
Claim 22
Dependent Claim
18 words
The piston as claimed in claim 10, wherein the top of insert is provided with a ceramic layer.
References Cited (Backward Citations)
US4530884A
Cited
US4334507A
Cited
US4254621A
Cited
US4495684A
Cited
US4523554A
Cited
US4599772A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-05 | 1991-10-05 | 1992-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-05 | 1995-10-05 | 1996-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-05 | 1999-10-05 | 2000-04-05 | $7700.00 | Window Closed / Lapsed |