US4873952A
Expired / Lapsed
US
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Engine cylinder head with precombustion chambers using porous ceramics insert
Assignee: Niterra Co Ltd
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Filing: 1988-02-26
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Granted: 1989-10-17
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Expires: 2008-02-26
Abstract
Abstract The invention relates to a cylinder head for an internal combustion engine in which each combustion chamber has a prechamber. A cast metal body of the cylinder head has recesses each of which provides a prechamber, and a hollow and, for example, bell-shaped member of a porous ceramics is cast-inserted in the inner surface defining each recess. Use is made of a ceramics low in thermal expansion coefficient and heat conductivity, such as aluminum titanate or cordierite, and the porosity of the ceramics is 5 to 50%. Because of its porousness the cast-inserted ceramics member is easily machine-finished. After that, for enhancement of strength and durability, the cast-inserted member of the porous ceramics is impregnated with an inorganic refractory material by using either a solution of, for example, sodium silicate or aluminum phosphate or an aqueous suspension of a ceramics powder, or a mixture of the solution and the suspension.
Inventors
- 👤 Yoshinori Narita
- 👤 Mitsuyoshi Kawamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:08
CPC Classifications
F; F02; F02B; F02B19/00; F02B19/16; F02B19/165; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/4927; Y10T29/49272
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
92 words
A cylinder head for an internal combustion engine, comprising: a cast metal body having at least one recess which provides a precombustion chamber; and a hollow member which is made of porous ceramics of which porosity is in the range from 5 to 50% and is cast-inserted in the inner wall surface of said cast metal body defining said recess such that the inner surface of the hollow member defines at least a major portion of the precombustion chamber, the cast-inserted hollow member being machine-finished and impregnated with an inorganic refractory material.
Claim 2
Dependent Claim
92 words
A cylinder head for an internal combustion engine, comprising: a cast metal body having at least one recess which provides a precombustion chamber; and a hollow member which is made of porous ceramics of which porosity is in the range from 5 to 50% and is cast-inserted in the inner wall surface of said cast metal body defining said recess such that the inner surface of the hollow member defines at least a major portion of the precombustion chamber, the cast-inserted hollow member being machine-finished and impregnated with an inorganic refractory material.
Claim 3
Dependent Claim
17 words
A cylinder head according to claim 1, wherein the principal component of said ceramics is aluminum titanate.
Claim 4
Dependent Claim
16 words
A cylinder head according to claim 1, wherein the principal component of said ceramics is cordierite.
Claim 5
Dependent Claim
25 words
A cylinder head according to claim 1, wherein said refractory material comprises a salt selected from the group consisting of sodium silicate and aluminum phosphate.
Claim 6
Dependent Claim
15 words
A cylinder head according to claim 4, wherein said refractory material comprises a ceramics powder.
Claim 7
Dependent Claim
31 words
A cylinder head according to claim 5, wherein said ceramics powder is a powder of at least one ceramics selected from the group consisting of aluminum titanate, cordierite, alumina and silica.
Claim 8
Dependent Claim
16 words
A cylinder head according to claim 1, wherein said hollow member comprises a generally semispherical part.
Claim 9
Dependent Claim
23 words
A cylinder head according to claim 7, wherein said hollow member further comprises a generally cylindrical part contiguous to said generally semispherical part.
Claim 10
Independent Claim
130 words
A method of producing a cylinder head for an internal combustion engine, comprising the steps of: casting a mtal into a cylinder head body having at least one recess which provides a precombustion chamber with insert of a hollow member made of a porous ceramics of which porosity is in the range from 5 to 50% for each of said at least one recess such that the inner-surface of the cast-inserted hollow member defines at least a major portion of the precombustion chamber; machine-finishing the cast-inserted hollow member; impregnating the machine-finished hollow ceramics member with a treatment liquid comprising an inorganic refractory material; and dissipating the liquid component of said treatment liquid from the hollow ceramics member to leave pores in the hollow ceramics member impregnated with said refractory material.
Claim 11
Independent Claim
130 words
A method of producing a cylinder head for an internal combustion engine, comprising the steps of: casting a mtal into a cylinder head body having at least one recess which provides a precombustion chamber with insert of a hollow member made of a porous ceramics of which porosity is in the range from 5 to 50% for each of said at least one recess such that the inner-surface of the cast-inserted hollow member defines at least a major portion of the precombustion chamber; machine-finishing the cast-inserted hollow member; impregnating the machine-finished hollow ceramics member with a treatment liquid comprising an inorganic refractory material; and dissipating the liquid component of said treatment liquid from the hollow ceramics member to leave pores in the hollow ceramics member impregnated with said refractory material.
Claim 12
Dependent Claim
17 words
A method according to claim 9, wherein the principal component of said porous ceramics is aluminum titanate.
Claim 13
Dependent Claim
16 words
A method according to claim 9, wherein the principal component of said porous ceramics is cordierite.
Claim 14
Dependent Claim
13 words
A method according to claim 9, wherein said treatment liquid is a solution.
Claim 15
Dependent Claim
22 words
A method according to claim 12, wherein said refractory material is selected from the group consisting of sodium silicate and aluminum phosphate.
Claim 16
Dependent Claim
17 words
A method according to claim 9, wherein said treatment liquid is a suspension of a ceramics powder.
Claim 17
Dependent Claim
30 words
A method according to claim 14, wherein said ceramics powder is a powder of at least one ceramics selected from the group consisting of aluminum titanate, cordierite, alumina and silica.
Claim 18
Dependent Claim
21 words
A method according to claim 14, wherein the liquid phase of said suspension comprises a solution of an inorganic refractory material.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
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