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US5099809A Expired / Lapsed US ⏱️ 0.0 years remaining

Combustion chamber for a diesel engine

Assignee: Mitsubishi Fuso Truck and Bus Corp
•
Filing: 1990-08-08
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Granted: 1992-03-31
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Expires: 2010-08-08
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Abstract

Abstract A projection positioned in the center of a concave section of a toroidal combustion chamber is divided into a section with a steep slope extending from the bottom to the head surface and a section with a gentle slope. The head surface is in the form of a flattened conical trapezoid. Because of its shape, the projection makes it possible for the air which is close to the center section to flow close to the surface of a side wall of the concave section. The air which had been at the center section is added to the amount of air supplied for combustion and is mixed with the fuel in the vicinity of the surface of the side wall of the concave section. By setting the angle at which the air flows along the side wall surface (re-entrant angle) in the combustion chamber, the flow of the air close to the side wall surface is made turbulent, which improves the agitation of the fuel.

Inventors

  • 👤 Toru Kawatani
  • 👤 Eiji Mizote
  • 👤 Susumu Kohketsu
  • 👤 Tomomi Nakagawa
  • 👤 Tetsuo Suzuki
  • 👤 Yoshihisa Yamaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 08:51
CPC Classifications
F; F02; F02B; F02B23/00; F02B23/02; F02B23/06; F02B23/0672; F02F; F02F3/00; F02F3/26; F02B23/0645; F02B23/0648; F02B23/0651; F02B2275/00; F02B2275/14; F02B3/00; F02B3/06; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 162 words
In an combustion chamber for a direct injection type of diesel engine comprising a built-up projection formed in a conical shape at the center of a bottom surface of a circular concave section which has a piston head section, and a peripheral edge section, formed as the arc of a circle, which is joined to this projection, and is connected to a side wall surface, the improvement, wherein the projection combines a bottom section positioned on a bottom surface side formed as a surface with a steep slope, and a top section positioned on a head section side formed as a conical trapezoid which has a gently sloping surface; the head angle of the conical trapezoid is formed 10° to 30° smaller than the cone angle of an injection nozzle; and the angle between the side wall surface of the combustion chamber and the sloped surface of the bottom section which faces the side wall surface is set at 0° to 30°.
Claim 2
Dependent Claim 162 words
In an combustion chamber for a direct injection type of diesel engine comprising a built-up projection formed in a conical shape at the center of a bottom surface of a circular concave section which has a piston head section, and a peripheral edge section, formed as the arc of a circle, which is joined to this projection, and is connected to a side wall surface, the improvement, wherein the projection combines a bottom section positioned on a bottom surface side formed as a surface with a steep slope, and a top section positioned on a head section side formed as a conical trapezoid which has a gently sloping surface; the head angle of the conical trapezoid is formed 10° to 30° smaller than the cone angle of an injection nozzle; and the angle between the side wall surface of the combustion chamber and the sloped surface of the bottom section which faces the side wall surface is set at 0° to 30°.
Claim 3
Dependent Claim 85 words
The combustion chamber for a diesel engine as claimed in claim 1, wherein the bottom surface of the concave section, which connects the bottom section and the side wall section of the projection, is formed in a shape which allows a spherical body to be rolled in the circumferential direction; and the radius R of the bottom surface is equal to 0.12 D to 0.18 D (R=0.12 D to 0.18 D), where D is the inner diameter of the open end of the combustion chamber.
Claim 4
Dependent Claim 27 words
The combustion chamber for a diesel engine as claimed in claim 1, wherein the re-entrant angle of the side wall surface is set at 20° to 25°.
Claim 5
Dependent Claim 43 words
The combustion chamber for a diesel engine as claimed in claims 1 to 3, wherein the height of the projection is such that the projection extends to a position at which it does not obstruct the spray of fuel from the injection nozzle.
Claim 6
Dependent Claim 121 words
The combustion chamber for a diesel engine as claimed in claim 1, wherein the bottom surface of the concave section which connects the bottom section and the side wall section of the projection has a curved surface 2'd with a radius of R 1 on the outer side which is connected to the side wall, and has a curved surface 2'e with a radius of R 2 on the inner side which is connected to the bottom section; and a flat section 2'f is provided between the curved surface 2'd on the outer side and the curved surface 2'e on the inner side, with the centers of the radii R 1 , R 2 being separated only by a distance a.

References Cited (Backward Citations)

US1865841A Cited
US4207843A Cited
US4281629A Cited
US4779587A Cited
US4953528A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-03-31 1995-09-30 1996-03-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-03-31 1999-09-30 2000-03-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-03-31 2003-09-30 2004-03-31 $7700.00 Window Closed / Lapsed

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