Combustion chamber for internal-combustion engine

Claim 2

In an internal-combustion engine of the compression ignition liquid fuel injection type having a cylinder, at least one piston reciprocative in the cylinder, a cylinder head disposed on the cylinder, a combustion chamber defined by the cylinder, the lower surface of the cylinder head and the upper surface of the piston, said lower surface and said upper surface constituting wall portions of said combustion chamber, a prechamber provided in the cylinder head so as to be in communication with the combustion chamber through a throat and into which a stream of fuel is directed, a wedge-shaped rectangular concavity provided in the upper surface of the piston in communication with the combustion chamber; the improvement comprising an air reservoir formed in one of the wall portions of the combustion chamber and spaced from the wedge-shaped rectangular concavity, the air reservoir being open at a maximum diameter portion thereof to the combustion chamber, whereby the air reservoir fills with compressed fresh air during a compression stroke of the engine and issues the compressed fresh air into the combustion chamber during a power stroke of the engine to promote complete combustion.

Claim 3

The improved internal-combustion engine recited in claim 1, wherein the air reservoir comprises at least one pair of holes provided at positions spaced radially in opposite directions from the longitudinal center line of the wedge-shaped rectangular concavity.

Claim 4

The internal-combustion engine of claim 2, wherein each of the air reservoir holes is positioned on a line making an angle of about 30° to 120° with the longitudinal center line of the rectangular concavity.

Claim 5

The internal-combustion engine of claim 3 wherein a ratio of diameter to deepness of each of the air reservoir holes is about 1 to 4.

Claim 6

The internal-combustion engine of claim 1, wherein the air reservoir is in the upper surface of the piston.

Claim 7

The internal-combustion engine of claim 1, wherein the air reservoir is in the lower surface of the cylinder head.

Claim 8

In an internal-combustion engine of the compression ignition liquid fuel injection type having a cylinder, at least one piston reciprocative in the cylinder, a cylinder head disposed on the cylinder, a swirl chamber provided in the cylinder head in communication with the cylinder through a throat, and a rectangular piston chamber provided in the upper surface of the piston, the improvement which comprises: said piston having at least one pair of air reservoir holes provided in the upper surface thereof symmetric with a longitudinal center line of the piston chamber on a line making an angle of about 30° to 120° with the longitudinal center line of the piston chamber, each of the air reservoir holes being deeper than the rectangular piston chamber.

Claim 9

In an internal-combustion engine of the compression ignition liquid fuel injection type having a cylinder, at least one piston reciprocative in the cylinder, a cylinder head disposed on the cylinder, a swirl chamber provided in the cylinder head in communication with the cylinder through a throat, and a rectangular piston chamber provided in the upper surface of the piston, the improvement which comprises: said piston having at least one pair of air reservoir holes provided in the upper surface thereof symmetric with a longitudinal center line of the piston chamber on a line making an angle of about 30° to 120° with the longitudinal center line of the piston chamber, each of the air reservoir holes being deeper than the rectangular piston chamber.

Claim 10

The internal-combustion engine of claim 7, wherein a ratio of diameter to deepness of each of the air reservoir holes is of a value of about 1 to 4.

Claim 11

In an internal-combustion engine having a cylinder block with at least one bore, a cylinder head disposed on the cylinder, a piston reciprocable in the cylinder bore, and the combustion chamber defined between the lower surface of the cylinder head and the upper surface of the piston, the improvement comprising: said piston having a wedge-shaped rectangular concavity formed in the upper surface thereof and forming part of the combustion chamber, an air reservoir formed in one of the upper surfaces of the piston and the lower surface of the cylinder head so that an open end thereof, through which the air reservoir communicates with the combustion chamber, is not directly opposed to a flow of injected fuel, said air reservoir being comprised of a pair of cylindrical holes arranged in symmetric relation with respect to a longitudinal central line of the wedge-shaped rectangular concavity, each cylindrical hole having a diameter-deepness ratio of approximately 1 to 4 and line connecting centers of each cylindrical hole and the piston making an angle of approximately 30° to 120° with the longitudinal center line of the wedge-shaped rectangular concavity, said cylinder head having a swirl chamber formed therein and connected by a passageway with the combustion chamber, fuel being injected into the swirl chamber, said wedge-shaped rectangular concavity positioned relative to said passageway such that a deeper portion of said concavity is directly opposed to the outlet of said passageway, whereby the air reservoir filled with compressed fresh air during a compression stroke of the engine issues the compressed fresh air into the combustion chamber during a power stroke of the engine to promote complete combustion.

Claim 12

In an internal-combustion engine having a cylinder block with at least one bore, a cylinder head disposed on the cylinder, a piston reciprocable in the cylinder bore, and the combustion chamber defined between the lower surface of the cylinder head and the upper surface of the piston, the improvement comprising: said piston having a wedge-shaped rectangular concavity formed in the upper surface thereof and forming part of the combustion chamber, an air reservoir formed in one of the upper surfaces of the piston and the lower surface of the cylinder head so that an open end thereof, through which the air reservoir communicates with the combustion chamber, is not directly opposed to a flow of injected fuel, said air reservoir being comprised of a pair of cylindrical holes arranged in symmetric relation with respect to a longitudinal central line of the wedge-shaped rectangular concavity, each cylindrical hole having a diameter-deepness ratio of approximately 1 to 4 and line connecting centers of each cylindrical hole and the piston making an angle of approximately 30° to 120° with the longitudinal center line of the wedge-shaped rectangular concavity, said cylinder head having a swirl chamber formed therein and connected by a passageway with the combustion chamber, fuel being injected into the swirl chamber, said wedge-shaped rectangular concavity positioned relative to said passageway such that a deeper portion of said concavity is directly opposed to the outlet of said passageway, whereby the air reservoir filled with compressed fresh air during a compression stroke of the engine issues the compressed fresh air into the combustion chamber during a power stroke of the engine to promote complete combustion.