US4708104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reinforced pistons
Assignee: AE PLC
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Filing: 1987-03-03
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Granted: 1987-11-24
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Expires: 2007-03-03
Abstract
Abstract A piston is manufactured by incorporating a reinforcement which is formed at least in part by a fibre material and which is so non-uniform as to provide differing characteristics in the cast piston in predetermined differing regions of the piston. For example, the volumetric density of the fibres may be different in one region of the reinforcement as compared with another region in order to produce a more resistant region in the cast piston. Additionally or alternatively, the reinforcement may hold finely divided materials which combine with the piston material during casting to give improved properties. Examples of this are the incorporation of particles of silicon, silicon carbide or silicon nitride to improve wear and/or the incorporation of molybdenum disulphide and tungsten disulphide or graphite to improve lubrication.
Inventors
- 👤 Roger A. Day
- 👤 Norman Tommis
- 👤 Andrew R. Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:56
CPC Classifications
B; B22; B22D; B22D19/00; B22D19/14; F; F02; F02F; F02F3/00; B22D19/0009; B22D19/0027; C; C22; C22C; C22C47/00; C22C47/08; F02B; F02B23/00; F02B23/02; F02B23/06; F02B23/0636; F02F7/00; F02F7/0085; F02F7/0087; B22F; B22F2998/00; F05; F05C; F05C2201/00; F05C2201/02; F05C2201/021; F05C2201/028; F05C2201/04; F05C2201/0433; F05C2201/0448; F05C2203/00; F05C2203/08; F05C2203/0804; F05C2203/0813; F05C2203/0817; F05C2203/083; F05C2203/0843; F05C2253/00; F05C2253/16; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249; Y10T29/49256; Y10T29/49259
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
117 words
A method of manufacturing a reinforced piston for an engine or compressor and comprising: preparing a reinforcement from fibres, incorporating in a region of the fibre reinforcement, a finely divided particulate material, a further region not incorporating finely divided particulate material, inserting said reinforcement incorporating said finely divided particulate material into a mould, fill the mould with molten metal, and then solidifying the molten metal under pressure so that the molten metal penetrates said region incorporating said finely divided particulate material and said further region not incorporating a finely divided particulate material to form a piston in which said region and said further region of the reinforcement provide different characteristics in respective different regions of the piston.
Claim 2
Independent Claim
117 words
A method of manufacturing a reinforced piston for an engine or compressor and comprising: preparing a reinforcement from fibres, incorporating in a region of the fibre reinforcement, a finely divided particulate material, a further region not incorporating finely divided particulate material, inserting said reinforcement incorporating said finely divided particulate material into a mould, fill the mould with molten metal, and then solidifying the molten metal under pressure so that the molten metal penetrates said region incorporating said finely divided particulate material and said further region not incorporating a finely divided particulate material to form a piston in which said region and said further region of the reinforcement provide different characteristics in respective different regions of the piston.
Claim 3
Dependent Claim
22 words
A method according to claim 1, wherein the finely divided material is a material which forms an alloy with the piston material.
Claim 4
Dependent Claim
32 words
A method according to claim 2, in which the piston material is an aluminium alloy and wherein the finely divided material is selected from the group comprising silicon, and a silicon compound.
Claim 5
Dependent Claim
29 words
A method according to claim 1, wherein the finely divided material is a material which which forms required surface properties in a particular region or regions of the piston.
Claim 6
Dependent Claim
37 words
A method according to claim 4, wherein the material is selected from the group comprising molybdenum disulphide, tungsten disulphide or graphite in order to reduce the coefficient of friction at the surface of the region or regions.
Claim 7
Dependent Claim
73 words
A method according to claim 1, wherein an additional non-uniformity of the reinforcement is provided by a variation of the volume percentage of the fibres within the reinforcement, so that a first characteristic is provided in a region or regions of the cast piston including a higher volume percentage of fibres and a second characteristic is provided in a region or regions of the cast piston including a lower volume percentage of fibres.
Claim 8
Dependent Claim
17 words
A method according to claim 6, wherein the first and second characteristics are provided by different fibres.
Claim 9
Dependent Claim
18 words
A method according to claim 6, wherein the volume percentage of fibres is varied between 1 and 25%.
Claim 10
Dependent Claim
52 words
A method according to claim 8, wherein in the region or regions of the cast piston having said first characteristic, there is 20 to 25% by volume of fibres and in the region or regions of the cast piston having said second characteristic, there is 1 to 10% by volume of fibres.
Claim 11
Dependent Claim
94 words
A piston for an internal combustion engine or compressor comprising: a squeeze cast piston body, a reinforcement formed of fibres and incorporated into the squeeze cast body during the casting and having a first region incorporating a finely divided particulate material and a second region incorporating a finely divided particulate material, a first region of the piston reinforced by said first region of said reinforcement and having first required characteristics, a second region reinforced by said second region of the reinforcement and having required characteristics different from the characteristics of said first piston region.
Claim 12
Dependent Claim
94 words
A piston for an internal combustion engine or compressor comprising: a squeeze cast piston body, a reinforcement formed of fibres and incorporated into the squeeze cast body during the casting and having a first region incorporating a finely divided particulate material and a second region incorporating a finely divided particulate material, a first region of the piston reinforced by said first region of said reinforcement and having first required characteristics, a second region reinforced by said second region of the reinforcement and having required characteristics different from the characteristics of said first piston region.
Claim 13
Dependent Claim
64 words
A piston according to claim 10, wherein additional non-uniformity of the reinforcement is provided by variation of the volume percentage of thefibres so that a first characteristic is provided in a region or regions of the piston including a higher volume percentage of fibres and a second characteristic is provided in a region or regions of the piston including lower volume percentage of fibres.
Claim 14
Dependent Claim
45 words
A piston according to claim 11, wherein the piston includes a crown and piston ring grooves, the reinforcement reinforcing both the crown and the piston ring grooves and having a greater volume percentage of fibres in the crown region than the piston ring groove region.
Claim 15
Dependent Claim
43 words
A piston according to claim 10, wherein the piston includes a crown portion and a piston ring groove portion and the reinforcement reinforces both portions, the reinforcement including a finely divided material for improving the properties of at least one of said portions.
Claim 16
Dependent Claim
49 words
A piston according to claim 13, wherein the piston has a piston ring band and a skirt, the reinforcement extending to these regions and including a particulate material which forms a surface having a lower coefficient of friction with an associated cylinder or liner than the unreinforced piston metal.
Claim 17
Dependent Claim
60 words
A reinforcement for incorporation in a piston for an engine or compressor in a squeeze casting process, the reinforcement being composed of fibres and having a first region incorporating a finely divided particulate material therein and a second region not incorporating finely divided material to produce required differing characteristics in the cast piston in predetermined differing regions of the piston.
Claim 18
Dependent Claim
60 words
A reinforcement for incorporation in a piston for an engine or compressor in a squeeze casting process, the reinforcement being composed of fibres and having a first region incorporating a finely divided particulate material therein and a second region not incorporating finely divided material to produce required differing characteristics in the cast piston in predetermined differing regions of the piston.
Claim 19
Dependent Claim
59 words
A reinforcement according to claim 15, wherein additional non-uniformity of the reinforcement is provided by the variation in the volume percentage of the fibres so that a first characteristic is provided in a region or regions of higher volume percentage of fibres and a second characteristic is provided in a region or regions of lower volume percentage of fibres.
Claim 20
Dependent Claim
50 words
A reinforcement according to claim 16, wherein non-uniformity of the reinforcement is provided by the provision, in at least one region of the fibres, of a finely divided material which, in combination with the piston material, produces, in the corresponding region or regions of the cast piston, the required characteristics.
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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) | 1990-11-23 | 1991-05-25 | 1991-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-23 | 1995-05-25 | 1995-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-23 | 1999-05-25 | 1999-11-24 | $7700.00 | Window Closed / Lapsed |