公开(公告)号：US09954344B2

公开(公告)日：2018-04-24

申请号：US15550458

申请日：2016-02-10

Applicant: DENSO CORPORATION

Inventor： Kenji Hattori ,  Masamichi Shibata ,  Toshiya Nakamura ,  Yasuomi Imanaka ,  Hirofumi Suzuki ,  Hiroshi Araki ,  Tomoyuki Watanabe ,  Shin Hase

IPC: H01T13/41 ,  H01T13/40 ,  H01C13/00 ,  F02P15/00

CPC classification number: H01T13/41 ,  F02P13/00 ,  F02P15/00 ,  H01C13/00 ,  H01T13/20

Abstract: A spark plug 1 includes a cylindrical housing, a cylindrical insulator, a center electrode, a terminal bracket, a ground electrode, and a resistor. The insulator is held on the inside of the housing. The center electrode 4 is held on the inside of the insulator, with a tip end being projected therefrom. The terminal bracket is held on the inside of the insulator, with a base end part and being projected therefrom. The ground electrode forms a spark discharge gap G between itself and the center electrode. The resistor contains carbon and is disposed on the inside of the insulator so as to be located between the center electrode 4 and the terminal bracket. In an axial direction X of the spark plug, the resistor has a higher carbon content in a first region positioned on a tip side, compared to a second region positioned on a base end side.

公开(公告)号：US09583916B2

公开(公告)日：2017-02-28

申请号：US15053256

申请日：2016-02-25

Applicant: DENSO CORPORATION

Inventor： Shota Imada ,  Hirofumi Suzuki ,  Hiroshi Araki

IPC: H01T13/38 ,  C04B35/00

CPC classification number: H01T13/38 ,  C04B35/00 ,  C04B35/111 ,  C04B35/117 ,  C04B2235/3201 ,  C04B2235/3206 ,  C04B2235/3208 ,  C04B2235/3222 ,  C04B2235/3418 ,  C04B2235/3472 ,  C04B2235/3481 ,  C04B2235/5409 ,  C04B2235/80 ,  C04B2235/9669

Abstract: An alumina sintered body has a main phase made of alumina crystals, a first dispersed phase made of MgAl2O4 dispersed in the main phase, and a second dispersed phase made of SiO2 and/or CaO dispersed in the main phase. A content ratio of the main phase is within a range from not less than 98% to less than 98%. The alumina sintered body satisfies a relationship of 100×I2/I1≧5.5%, where I1 indicates a maximum peak height intensity derived from alumina, and I2 indicates a maximum peak height intensity derived from MgAl2O4 in a X-ray diffraction of the alumina sintered body. An area ratio of the second dispersed phase on a surface of the alumina sintered body is not more than 15.2%. A spark plug has a central electrode, a ground electrode and an insulator made of the alumina sintered body having the specific features previously described.

Abstract translation: 氧化铝烧结体具有由氧化铝晶体制成的主相，分散在主相中的分散在MgAl 2 O 4中的第一分散相和分散在主相中的SiO 2和/或CaO制成的第二分散相。 主相的含有率在98％以上且小于98％的范围内。 氧化铝烧结体满足100×I2 /I1≥5.5％的关系，其中I1表示由氧化铝衍生的最大峰高强度，I2表示在氧化铝烧结体的X射线衍射中来自MgAl 2 O 4的最大峰高强度 身体。 第二分散相在氧化铝烧结体表面的面积比不大于15.2％。 火花塞具有中心电极，接地电极和由具有前述具体特征的氧化铝烧结体制成的绝缘体。