SPARK-IGNITION INTERNAL COMBUSTION ENGINE

• US 20200131978A1
• Filed: 02/27/2018
• Published: 04/30/2020
• Est. Priority Date: 03/27/2017
• Status: Active Grant

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Aoki, Shuma, Muranaka, Hiroaki, Yamaguchi, Naohiro, Wada, Yoshitaka
• Granted Patent: US 10,968,817 B2
• Time in Patent Office: Days
• CPC Class Codes: F02B 2023/106 Tumble flow, i.e. the axis of rotation of the main charge flow motion is horizontal
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02B 2275/48 Tumble motion in gas movement in cylinder
• CPC Class Codes: F02B 23/104 the injector being placed on a side position of the cylinder
• CPC Class Codes: F02B 31/08 having multiple air inlets
• CPC Class Codes: F02F 1/42 Shape or arrangement of intake or exhaust channels in cylinder heads
• CPC Class Codes: F02F 1/4214 specially adapted for four or more valves per cylinder
• CPC Class Codes: F02F 2001/245 the valve stems being orientated at an angle with the cylinder axis
• CPC Class Codes: F02F 3/26 having combustion chamber in piston head the surface thereof being covered F02F3/14
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In a spark-ignition internal combustion engine in which a protrusion including an intake-side inclined surface and an exhaust-side inclined surface is formed on a top surface of a piston, and a cavity is formed in the protrusion at a position associated with a spark plug, the intake-side inclined surface and the exhaust-side inclined surface are formed in such a way that an inclination angle of the exhaust-side inclined surface is smaller than an inclination angle of the intake-side inclined surface, and a difference in inclination angle between the intake-side inclined surface and the exhaust-side inclined surface is 4 degrees or larger.

Claims

1. A spark-ignition internal combustion engine comprising:

a cylinder;

a piston disposed to be reciprocatively movable within the cylinder;

a cylinder head disposed above the cylinder, and configured to form a pent-roof combustion chamber in cooperation with an inner peripheral surface of the cylinder and a top surface of the piston; and

a spark plug disposed in the cylinder head in such a way as to face the combustion chamber, wherein

a protrusion including an intake-side inclined surface and an exhaust-side inclined surface along a ceiling surface of the combustion chamber is formed on the top surface of the piston,

a downwardly recessed cavity is formed in the protrusion at a position associated with the spark plug,

an intake port capable of generating a tumble flow within the combustion chamber is formed in the cylinder head, and the intake-side inclined surface and the exhaust-side intake surface are formed in such a way that an inclination angle of the exhaust-side inclined surface is smaller than an inclination angle of the intake-side inclined surface, and a difference in inclination angle between the intake-side inclined surface and the exhaust-side inclined surface is 4 degrees or larger.

2. The spark-ignition internal combustion engine according to claim 1, wherein

the intake-side inclined surface is formed in such a way as to be orthogonal to a valve axis line of an intake valve, and

the exhaust-side inclined surface is formed in such a way as to be orthogonal to a valve axis line of an exhaust valve.

3. The spark-ignition internal combustion engine according to claim 1, wherein

a geometric compression ratio of the cylinder is 12 or larger.

4. The spark-ignition internal combustion engine according to claim 2, wherein

a geometric compression ratio of the cylinder is 12 or larger.