US4440069A
Expired / Lapsed
US
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Composite piston and process
Assignee: BP Corp North America Inc
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Filing: 1982-06-11
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Granted: 1984-04-03
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Expires: 2002-06-11
Abstract
Abstract A lightweight composite piston is provided to decrease fuel consumption, attenuate noise, and permit increased speed of operation.
Inventors
- 👤 Matthew W. Holtzberg
- 👤 Steven J. Henke
- 👤 Lawrence D. Spaulding
- 👤 James C. Oakley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 04:12
CPC Classifications
F; F02; F02F; F02F3/00; F02F3/0015; F02F3/003; F02F7/00; F02F7/0085; F16; F16J; F16J1/00; F16J1/02; F02B; F02B2275/00; F02B2275/34; F02F2200/00; F02F2200/04; F05; F05C; F05C2201/00; F05C2201/02; F05C2201/021; F05C2201/04; F05C2201/0433; F05C2201/0448; F05C2203/00; F05C2203/08; F05C2203/0865; F05C2203/0882; F05C2225/00; F05C2225/02; F05C2251/00; F05C2251/04; F05C2251/042; F05C2253/00; F05C2253/16; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249; Y10T29/49256
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
187 words
A composite piston, comprising: a metal head having an annular wall defining a set of piston ring-receiving grooves, a transverse disc extending laterally between and connecting said annular wall for compressing an air fuel mixture, and a pair of legs extending longitudinally from said disc and spaced radially inwardly from said annular wall and defining a pair of diametrically opposed leg holes; and a thermoplastic, amide-imide resinous polymeric skirt having an elongated annular wall portion and a pair of bosses extending radially inwardly from said wall portion, said wall portion positioned in general longitudinal alignment with and cooperating with said annular wall of said head to define a composite piston wall for reciprocatingly sliding against a cylinder wall, said wall portion annularly surrounding said legs, said bosses connected to said legs and defining a pair of diametrically opposed skirt holes, and said skirt holes and said leg holes being transversely aligned in registration with each other and being of a sufficient size for pivotally receiving a wrist pin; and said amide-imide skirt and said metal head maintaining their structural relationship, shape and integrity at engine operating conditions.
Claim 2
Dependent Claim
187 words
A composite piston, comprising: a metal head having an annular wall defining a set of piston ring-receiving grooves, a transverse disc extending laterally between and connecting said annular wall for compressing an air fuel mixture, and a pair of legs extending longitudinally from said disc and spaced radially inwardly from said annular wall and defining a pair of diametrically opposed leg holes; and a thermoplastic, amide-imide resinous polymeric skirt having an elongated annular wall portion and a pair of bosses extending radially inwardly from said wall portion, said wall portion positioned in general longitudinal alignment with and cooperating with said annular wall of said head to define a composite piston wall for reciprocatingly sliding against a cylinder wall, said wall portion annularly surrounding said legs, said bosses connected to said legs and defining a pair of diametrically opposed skirt holes, and said skirt holes and said leg holes being transversely aligned in registration with each other and being of a sufficient size for pivotally receiving a wrist pin; and said amide-imide skirt and said metal head maintaining their structural relationship, shape and integrity at engine operating conditions.
Claim 3
Dependent Claim
18 words
A composite piston in accordance with claim 1 wherein said annular wall defines a plurality of oil apertures.
Claim 4
Dependent Claim
49 words
A composite piston in accordance with claim 1 wherein said amide-imide skirt has a pair of longitudinally spaced shoulders on opposite ends of each skirt hole, said shoulders each having a transverse ledge and cooperating with each other to define a generally rectangular transverse recess about each skirt hole.
Claim 5
Dependent Claim
19 words
A composite piston in accordance with claim 3 wherein at least one of said ledges defines oil retention grooves.
Claim 6
Dependent Claim
39 words
A composite piston in accordance with claim 1 wherein said amide-imide skirt defines retaining ring-receiving grooves about said skirt, holes and said wall portion of said amide-imide skirt is substantially longer than said annular wall of said metal head.
Claim 7
Dependent Claim
38 words
A composite piston in accordance with claim 1 wherein the maximum transverse span of said legs is slightly greater than the distance between said bosses, and said legs and said bosses are in press-fitting engagement with each other.
Claim 8
Dependent Claim
17 words
A composite piston in accordance with claim 1 including means for connecting said legs to said bosses.
Claim 9
Dependent Claim
14 words
A composite piston in accordance with claim 1 wherein said disc is substantially circular.
Claim 10
Dependent Claim
14 words
A composite piston in accordance with claim 1 wherein said disc is generally elliptical.
Claim 11
Dependent Claim
17 words
A composite piston in accordance with claim 1 wherein said disc defines a plurality of valve seats.
Claim 12
Dependent Claim
18 words
A composite poiston in accordance with claim 1 wherein said metal head consists essentially of aluminum and steel.
Claim 13
Dependent Claim
30 words
A composite engine part in accordance with claim 1 wherein said amide-imide skirt comprises a reaction product of a trifunctional carboxylic acid compound and at least one diprimary aromatic diamine.
Claim 14
Dependent Claim
154 words
A composite engine part in accordance with claim 12 wherein said amide-imide skirt comprises at least one of the following moieties: ##STR8## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1 and R 2 are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2 --, and --S--radicals and wherein said R 1 and R 2 containing units run from about 10 mole percent R 1 containing unit and about 90 mole percent R 2 containing unit to about 90 mole percent R 1 containing unit and about 10 mole percent R 2 containing unit.
Claim 15
Dependent Claim
14 words
A composite engine part in accordance with claim 13 wherein R 1 is ##STR9##
Claim 16
Dependent Claim
67 words
A composite engine part in accordance with claim 13 wherein Z is a trivalent benzene ring, ##STR10## and wherein the concentration range runs from about 30 mole percent of the R 1 containing units and about 70 mole percent of the R 2 containing units to about 70 mole percent of the R 1 containing units and about 30 mole percent of the R 2 containing units.
Claim 17
Dependent Claim
23 words
A composite engine part in accordance with claim 13 wnerein said amide-imide skirt comprises from 40% to 100% by weight amide-imide resinous polymer.
Claim 18
Dependent Claim
23 words
A composite engine part in accordance with claim 16 wherein said amide-imide skirt comprises from 65% to 75% by weight amide-imide resinous polymer.
Claim 19
Dependent Claim
30 words
A composite engine part in part in accordance with claim 13 wherein said amide-imide skirt comprises a fibrous reinforcing material selected from the group consisting essentially of graphite and glass.
Claim 20
Dependent Claim
21 words
A composite engine part in accordance with claim 18 wherein said amide-imide skirt comprises from 10% to 50% by weight graphite.
Claim 21
Dependent Claim
21 words
A composite engine part in accordance with claim 19 wherein said amide-imide skirt comprises from 30% to 34% by weight graphite.
Claim 22
Dependent Claim
20 words
A composite engine part in accordance with claim 18 wherein said amide-imide skirt comprises 10% to 60% by weight glass.
Claim 23
Dependent Claim
20 words
A composite engine part in accordance with claim 21 wherein said amide-imide skirt comprises 30% to 34% by weight glass.
Claim 24
Dependent Claim
28 words
A composite engine part in accordance with claim 18 wherein said fibrous reinforcing material has a polymeric sizing that substantially maintains its structural integrity at engine operating conditions.
Claim 25
Dependent Claim
21 words
A composite engine part in accordance with claim 18 wherein said amide-imide skirt comprises not greater than 3% by weight polytetrafluoroethylene.
Claim 26
Dependent Claim
21 words
A composite engine part in accordance with claim 24 wherein said amide-imide skirt comprises from 1/2% to 1% by weight polytetrafluoroethylene.
Claim 27
Dependent Claim
22 words
A composite engine part in accordance with claim 18 wherein said amide-imide skirt comprises not more than 6% by weight titanium dioxide.
Claim 28
Dependent Claim
182 words
A process for forming a composite piston, comprising the steps of: injection molding a thermoplastic, amide-imide resinous polymer to form an amide-imide skirt having a pair of inwardly extending bosses defining a pair of skirt holes; allowing said amide-imide resinous polymeric skirt to cool below its plastic deformation temperature; post curing said amide-imide skirt by solid state polymerization to enhance the strength and integrity of said amide-imide skirt; turning a metal head on a lathe to form an annular wall defining a set of piston ring-receiving grooves and a substantially circular disc extending across said annular wall, cutting a pair of metal legs extending axially from said disc on a milling machine, and drilling a pair of aligned holes in said metal legs; connecting said amide-imide skirt to said head by press fitting said bosses against said metal legs until said amide-imide skirt abuts against said annular wall said amide-imide skirt abuts against said annular wall of said metal head; and honing said holes in said amide-imide skirt and said metal legs to a sufficient size to pivotally receive a wrist pin.
Claim 29
Dependent Claim
182 words
A process for forming a composite piston, comprising the steps of: injection molding a thermoplastic, amide-imide resinous polymer to form an amide-imide skirt having a pair of inwardly extending bosses defining a pair of skirt holes; allowing said amide-imide resinous polymeric skirt to cool below its plastic deformation temperature; post curing said amide-imide skirt by solid state polymerization to enhance the strength and integrity of said amide-imide skirt; turning a metal head on a lathe to form an annular wall defining a set of piston ring-receiving grooves and a substantially circular disc extending across said annular wall, cutting a pair of metal legs extending axially from said disc on a milling machine, and drilling a pair of aligned holes in said metal legs; connecting said amide-imide skirt to said head by press fitting said bosses against said metal legs until said amide-imide skirt abuts against said annular wall said amide-imide skirt abuts against said annular wall of said metal head; and honing said holes in said amide-imide skirt and said metal legs to a sufficient size to pivotally receive a wrist pin.
Claim 30
Dependent Claim
18 words
A process in accordance with claim 27 including drilling a set of oil holes in said annular wall.
Claim 31
Dependent Claim
17 words
A process in accordance with claim 27 wherein said metal head consists essentially of aluminum and steel.
Claim 32
Dependent Claim
27 words
A process in accordance with claim 27 wherein said amide-imide polymer is prepared by reacting a trifunctional carboxylic acid compound with at least one diprimary aromatic diamine.
Claim 33
Dependent Claim
151 words
A process in accordance with claim 30 wherein said amide-imide polymer comprises one of the following moieties: ##STR11## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1 and R 2 are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2 --, and --S-- radicals and wherein said R 1 and R 2 containing units run from about 10 mole percent R 1 containing unit and about 90 mole percent R 2 containing unit to about 90 mole percent R 1 containing unit and about 10 mole percent R 2 containing unit.
Claim 34
Dependent Claim
12 words
A process in accordance with claim 31 wherein R 1 is ##STR12##
Claim 35
Dependent Claim
65 words
A process in accordance with claim 31 wherein Z is a trivalent benzene ring, ##STR13## and wherein the concentration range runs from about 30 mole percent of the R 1 containing units and about 70 mole percent of the R 2 containing units to about 70 mole percent of the R 1 containing units and about 30 mole percent of the R 2 containing units.
Claim 36
Dependent Claim
19 words
A process in accordance with claim 31 wherein said polymer comprises from 10% to 50% by weight graphite fibers.
Claim 37
Dependent Claim
19 words
A process in accordance with claim 34 wherein said polymer comprises from 30% to 34% by weight graphite fibers.
Claim 38
Dependent Claim
19 words
A process in accordance with claim 31 wherein said polymer comprises from 10% to 60% by weight glass fibers.
Claim 39
Dependent Claim
19 words
A process in accordance with claim 36 wherein said polymer comprises from 30% to 34% by weight glass fibers.
Claim 40
Dependent Claim
110 words
A process in accordance with claim 27 wherein said injection molding includes partially opening a mold having a generally skirt-shaped cavity, placing a dam adjacent the partially opened portion of said mold, injecting said polymer at its melt temperature into said cavity until said cavity is substantially filled with said polymer, substantially preventing said polymer from flowing out of said partially opened portion of said mold with said dam, and closing said mold while said polymer is above its plastic deformation temperature to compress said polymer; and said cooling includes cooling said polymer in said closed mold below its plastic deformation temperature to solidify the shape of the molded skirt.
Claim 41
Dependent Claim
14 words
A process in accordance with claim 38 wherein said mold is closed by clamping.
Claim 42
Dependent Claim
15 words
A process in accordance with claim 39 wherein said dam is removed before said clamping.
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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) | 1987-04-03 | 1987-10-03 | 1988-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-03 | 1991-10-03 | 1992-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-03 | 1995-10-03 | 1996-04-03 | $7700.00 | Window Closed / Lapsed |