US5097807A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combustion chamber for diesel engines
Assignee: NGK Insulators Ltd
•
Filing: 1991-03-29
•
Granted: 1992-03-24
•
Expires: 2011-03-29
Abstract
Abstract The disclosure relates to a novel arrangement of a combustion chamber for diesel engines, which is defined by an inner wall including a fuel-impinging area formed of a metallic material, and a remaining area which at least partly is formed of a ceramic material or a like heat-resisting material. The arrangement serves to achieve an effective exhaust gas clarification, including the minimization of NOx emission, and to realize increased power output and reduced fuel consumption of the engine.
Inventors
- 👤 Hiroshi Oikawa
- 👤 Naohisa Nakashima
- 👤 Minoru Matsui
- 👤 Tadao Ozawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:14
CPC Classifications
F; F02; F02B; F02B23/00; F02B23/02; F02B23/06; F02B23/0672; F02B23/0603; F02B23/0636; F02B23/0639; F02B23/0642; F02B23/0696; F02F; F02F3/00; F02F3/10; F02F3/12; F02B2023/0612; F02B2275/00; F02B2275/14; F02B2275/40; F02B23/0645; F02B23/0669; F02B3/00; F02B3/06; F02F1/00; F02F1/24; F02F2001/244; F02F2001/247; F02F2001/249; F05; F05C; F05C2201/00; F05C2201/02; F05C2201/021; F05C2201/04; F05C2201/0433; F05C2201/0448; F05C2201/046; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
169 words
A combustion chamber for a diesel engine, comprising: an inner wall comprising (a) a fuel impinging area upon which fuel is directly injected, said fuel impinging area comprising a top surface of a piston head and an inner wall of a cavity formed in said piston head, and consisting essentially of a thermally conductive metallic member, and (b) a remaining area which is shielded from direct injection of fuel and which at least partially consists of a heat-resisting material, said remaining area comprising a first layer of heat-resisting material arranged beneath a lower surface of a cylinder head; and a sintered ceramic body consisting of partially stabilized zirconia arranged between said lower surface of said cylinder head and said first layer of heat-resisting material; wherein that portion of said combustion chamber inner wall which is formed of said heat-resisting material has a surface area ratio of at least 40% with respect to a total surface area of said combustion chamber inner wall except a surface area of said cavity.
Claim 2
Dependent Claim
169 words
A combustion chamber for a diesel engine, comprising: an inner wall comprising (a) a fuel impinging area upon which fuel is directly injected, said fuel impinging area comprising a top surface of a piston head and an inner wall of a cavity formed in said piston head, and consisting essentially of a thermally conductive metallic member, and (b) a remaining area which is shielded from direct injection of fuel and which at least partially consists of a heat-resisting material, said remaining area comprising a first layer of heat-resisting material arranged beneath a lower surface of a cylinder head; and a sintered ceramic body consisting of partially stabilized zirconia arranged between said lower surface of said cylinder head and said first layer of heat-resisting material; wherein that portion of said combustion chamber inner wall which is formed of said heat-resisting material has a surface area ratio of at least 40% with respect to a total surface area of said combustion chamber inner wall except a surface area of said cavity.
Claim 3
Dependent Claim
20 words
The combustion chamber of claim 1, wherein said surface area ratio of said heat-resisting material portion is at least 70%.
Claim 4
Dependent Claim
28 words
The combustion chamber of claim 1, wherein said remaining area further comprises a top surface of a piston head, which at least partially consists of said heat-resisting material.
Claim 5
Dependent Claim
28 words
The combustion chamber of claim 1, wherein said remaining area further comprises an inner surface of a cylinder liner, which at least partially consists of said heat-resisting material.
Claim 6
Dependent Claim
39 words
The combustion chamber of claim 4, wherein that portion of said cylinder liner which is formed of said heat-resisting material has an axial length of at least 5 mm as measured from a top end of said cylinder liner.
Claim 7
Dependent Claim
22 words
The combustion chamber of claim 1, wherein said sintered ceramic body has a heat conductivity which is not greater than 0.02 cal/cm.s.°C.
Claim 8
Dependent Claim
20 words
The combustion chamber of claim 1, wherein said heat-resisting material is at least partially surrounded by a heat-insulating air layer.
Claim 9
Dependent Claim
26 words
The combustion chamber of claim 1, wherein said heat-resisting material comprises at least one member selected from the group consisting of ceramic material and heat-resisting metal.
Claim 10
Dependent Claim
30 words
The combustion chamber of claim 8, wherein said ceramic material comprises at least one member selected from the group consisting of a sintered ceramic body and a ceramic coated layer.
Claim 11
Dependent Claim
33 words
The combustion chamber of claim 9, wherein said sintered ceramic body comprises at least one member selected from the group consisting of partially stabilized zirconia mullite, silicon nitride, sialon, alumina, and silicon carbide.
Claim 12
Dependent Claim
33 words
The combustion chamber of claim 9, wherein said ceramic coated layer comprises at least one member selected from the group consisting of zirconia, chromium oxide, mullite, silicon nitride, sialon, alumina, and silicon carbide.
Claim 13
Dependent Claim
32 words
The combustion chamber of claim 8, wherein said heat-resisting metal comprises at least one member selected from the group consisting of stainless steel, nickel-based super-alloy, cobalt-based super-alloy, and heat resisting cast steel.
Claim 14
Dependent Claim
16 words
The combustion chamber of claim 1, wherein said chamber is for a naturally aspirated diesel engine.
Claim 15
Dependent Claim
186 words
A combustion chamber for a diesel engine, comprising: an inner wall comprising: (a) a fuel impinging area upon which fuel is directly injected, said fuel impinging area comprising a top surface of a piston head and an inner wall of a cavity formed in said piston head, and consisting essentially of a thermally conductive metallic member, and (b) a remaining area which is shielded from direct injection of fuel and which at least partially consists of a heat-resisting material, said remaining area comprising a first layer of heat-resisting material arranged beneath a lower surface of a cylinder head and arranged on at least a portion of an outer peripheral surface of a piston top land; and a sintered ceramic body consisting of partially stabilized zirconia arranged between said lower surface of said cylinder head and said first layer of heat-resisting material; wherein that portion of said combustion chamber inner wall which is formed of said heat-resisting material has a surface area ratio of at least 40% with respect to a total surface area of said combustion chamber inner wall except a surface area of said cavity.
Claim 16
Dependent Claim
186 words
A combustion chamber for a diesel engine, comprising: an inner wall comprising: (a) a fuel impinging area upon which fuel is directly injected, said fuel impinging area comprising a top surface of a piston head and an inner wall of a cavity formed in said piston head, and consisting essentially of a thermally conductive metallic member, and (b) a remaining area which is shielded from direct injection of fuel and which at least partially consists of a heat-resisting material, said remaining area comprising a first layer of heat-resisting material arranged beneath a lower surface of a cylinder head and arranged on at least a portion of an outer peripheral surface of a piston top land; and a sintered ceramic body consisting of partially stabilized zirconia arranged between said lower surface of said cylinder head and said first layer of heat-resisting material; wherein that portion of said combustion chamber inner wall which is formed of said heat-resisting material has a surface area ratio of at least 40% with respect to a total surface area of said combustion chamber inner wall except a surface area of said cavity.
Claim 17
Dependent Claim
28 words
The combustion chamber of claim 14, wherein said remaining area further comprises a top surface of a piston head, which at least partially consists of said heat-resisting material.
Claim 18
Dependent Claim
28 words
The combustion chamber of claim 14, wherein said remaining area further comprises an inner surface of a cylinder liner, which at least partially consists of said heat-resisting material.
Claim 19
Dependent Claim
20 words
The combustion chamber of claim 14, wherein said heat-resisting material is at least partially surrounded by a heat-insulating air layer.
Claim 20
Dependent Claim
22 words
The combustion chamber of claim 14, wherein said ceramic sintered body has a heat conductivity which is not greater than 0.02 cal/cm.s.°C.
Claim 21
Dependent Claim
26 words
The combustion chamber of claim 14, wherein said heat-resisting material comprises at least one member selected from the group consisting of ceramic material and heat-resisting metal.
References Cited (Backward Citations)
GB579616A
Cited
FR1182853A
Cited
US3408995A
Cited
FR2089242A5
Cited
DE2439806A1
Cited
US4074671A
Cited
GB2061383A
Cited
US4344390A
Cited
US4532896A
Cited
JPS6030451A
Cited
JPS6090955A
Cited
JPS61218715A
Cited
US4774926A
Cited
US4796572A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-03-24 | 1995-09-23 | 1996-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-24 | 1999-09-23 | 2000-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-24 | 2003-09-23 | 2004-03-24 | $7700.00 | Window Closed / Lapsed |