公开(公告)号：US4289990A

公开(公告)日：1981-09-15

申请号：US20323

申请日：1979-03-14

申请人： Kazuhisa Mayumi ,  Katsumi Suzuki ,  Fujio Tsuboi

发明人： Kazuhisa Mayumi ,  Katsumi Suzuki ,  Fujio Tsuboi

IPC分类号： H01T13/20 ,  H01T13/14 ,  H01T13/32

CPC分类号： H01T13/14

摘要： A spark plug is disclosed, in which the insulator is formed with a stepped portion near its tip portion and the housing which surrounds the insulator is formed with an inner constriction which opposes the smaller portion of the insulator, near the stepped portion, with a small annular gap being left therebetween, thereby hindering the entry of air/fuel mixture and carbon particles into the inner space between the housing and the insulator, and thus reducing the buildup of carbon on the insulator.

摘要翻译： 公开了一种火花塞，其中绝缘体在其顶端部分附近形成有阶梯部分，并且围绕绝缘体的壳体形成有内部收缩部，该内部收缩部与台阶部分附近的绝缘体的较小部分相对， 留在其间的环形间隙，从而阻碍空气/燃料混合物和碳颗粒进入壳体和绝缘体之间的内部空间，从而减少绝缘体上碳的累积。