SPARK PLUG FOR INTERNAL COMBUSTION ENGINE, AND INTERNAL COMBUSTION ENGINE

• Main Author: SUGIURA AKIMITSU
• Format: Patent
• Language: English; Japanese
• Published: 27.12.2021
• Subjects: BASIC ELECTRIC ELEMENTS; CORONA DEVICES; ELECTRICITY; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARK GAPS; SPARKING PLUGS

To provide a spark plug for an internal combustion engine and the internal combustion engine which allow improvement in combustion efficiency.SOLUTION: A spark plug 1 for an internal combustion engine has: a cylindrical insulator 3; a center electrode 4 which is held on an inner peripheral side of the insulator 3 and has a tip end protruding part 41 protruding from the insulator 3 toward a tip end side; a cylindrical housing 2 which holds the insulator 3 on the inner peripheral side; and a plug cover 5 which is provided at a tip end of the housing 2 such that the same covers a sub-combustion chamber 50 where the tip end protruding part 41 is located. The plug cover 5 has a protruding cylindrical part 53 which protrudes from a tip end wall part 54 toward the sub-combustion chamber 50 and is internally provided with an axial nozzle hole 511. A lateral nozzle hole 516 for bringing the sub-combustion chamber 50 into communication with an outside is formed further on the outer peripheral side of the plug cover 5 than the protruding cylindrical part 53. The protruding cylindrical part 53 is shaped such that an outer shape of its cross section perpendicular to a plug axis direction Z has a plurality of protruding corner parts 531.SELECTED DRAWING: Figure 1 【課題】燃焼効率の向上を図ることができる内燃機関用のスパークプラグ及び内燃機関を提供すること。【解決手段】内燃機関用のスパークプラグ１は、筒状の絶縁碍子３と、絶縁碍子３の内周側に保持されると共に絶縁碍子３から先端側に突出する先端突出部４１を有する中心電極４と、絶縁碍子３を内周側に保持する筒状のハウジング２と、先端突出部４１が配される副燃焼室５０を覆うようハウジング２の先端部に設けられたプラグカバー５と、を有する。プラグカバー５は、先端壁部５４から副燃焼室５０へ向かって突出すると共に内側に軸方向噴孔５１１を備えた突出筒状部５３を有する。プラグカバー５における突出筒状部５３よりも外周側に、副燃焼室５０と外部とを連通させる側方噴孔５１６が形成されている。突出筒状部５３は、プラグ軸方向Ｚに直交する断面の外形が、複数の凸角部５３１を備えた形状である。【選択図】図１