COMBUSTION CHAMBER STRUCTURE FOR ENGINE

• Main Authors: HONDA YUYA, INOUE ATSUSHI, KONO MICHIHARU, UEKI YOSHIHARU, IMAMURA SATOSHI, NAKAHARA KOJI, ONISHI KENTO, MATSUMOTO KOTA, FUKUMA MASANARI
• Format: Patent
• Language: English; Japanese
• Published: 23.05.2019
• Subjects: ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES; BLASTING; COMBUSTION ENGINES; COMBUSTION ENGINES IN GENERAL; CONTROLLING COMBUSTION ENGINES; CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INTERNAL-COMBUSTION PISTON ENGINES; LIGHTING; MECHANICAL ENGINEERING; WEAPONS

To provide a combustion chamber structure for an engine, capable of securing high ignitability of air-fuel mixture by making the air-fuel mixture exist on an ignition part of a spark plug and in its vicinity during ignition.SOLUTION: A crown surface 50 of a piston 5 is provided with a cavity 51 recessed in a cylinder axial direction. The cavity 51 is provided in a region including a lower area of the ignition part of the spark plug in plan view from the cylinder axial direction. In plan-viewing the cavity 51 from the cylinder axial direction, the peripheral edge of the cavity 51 is provided with a lateral erected surface part 512 further erected in the cylinder axial direction than a bottom surface part 511 inside of the peripheral part. The lateral erected surface part 512 is provided at a position where the ignition part of the spark plug is held in a X-direction when the piston 5 is at a compression top dead center, for functioning as a guide part to guide air-fuel mixture from a combustion chamber to the ignition part of the spark plug.SELECTED DRAWING: Figure 4 【課題】着火時に混合気を点火プラグの着火部及びその周辺に存在させることにより、混合気の高い着火性を確保することができるエンジンの燃焼室構造を提供する。【解決手段】ピストン５の冠面５０に気筒軸方向に凹設されてなるキャビティ５１を有する。キャビティ５１は、気筒軸方向からの平面視で点火プラグの着火部の下方を含む領域に設けられている。キャビティ５１を気筒軸方向から平面視するとき、キャビティ５１の周縁部に、当該周縁部よりも内側の底面部５１１よりも、気筒軸方向に立上った側方立面部５１２が設けられている。側方立面部５１２は、ピストン５が圧縮上死点にあるときに点火プラグの着火部をＸ方向に挟む位置に設けられており、燃焼室内での混合気を点火プラグの着火部に案内する案内部として機能する。【選択図】図４