Ignition apparatus

Patent metadata

Field	Value
Publication number	US-10291000-B2
Application number	US-201615743732-A
Country	US
Kind code	B2
Filing date	Jul 5, 2016
Priority date	Jul 13, 2015
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

An ignition apparatus includes a spark plug and an ignition coil. The spark plug has a plug terminal protruding proximalward from an insulator. The ignition coil includes a coil main body, which includes a primary coil and a secondary coil, and a helical spring that electrically connects the secondary coil and the plug terminal. The plug terminal is made of a material that is both electrically conductive and magnetic. The plug terminal includes a terminal main body, which has an outer diameter greater than an inner diameter of the spring, and a terminal extension portion that has an outer diameter less than the inner diameter of the spring and extends proximalward from the terminal main body. A distal end portion of the spring abuts the terminal main body. The terminal extension portion is inserted and arranged in the spring. Between an outer circumferential surface of the terminal extension portion and an inner circumferential surface of the spring, there is interposed an insulating member.

First claim

The invention claimed is:

1. An ignition apparatus comprising:
a spark plug to be used as an ignition means for an internal combustion engine; and
an ignition coil that applies a high voltage to the spark plug,
wherein
the spark plug has a plug terminal electrically connected with a center electrode and protruding proximalward from an insulator,
the ignition coil includes a coil main body, which includes a primary coil and a secondary coil, and a helical spring that electrically connects the secondary coil and the plug terminal,
the plug terminal is made of a material that is both electrically conductive and magnetic,
the plug terminal includes a terminal main body, which has an outer diameter greater than an inner diameter of the spring, and a terminal extension portion that has an outer diameter less than the inner diameter of the spring and extends proximalward from the terminal main body,
a distal end portion of the spring abuts the terminal main body,
the terminal extension portion is inserted and arranged in the spring, and
between an outer circumferential surface of the terminal extension portion and an inner circumferential surface of the spring, there is interposed an insulating member.

2. The ignition apparatus as set forth in claim 1 , wherein the insulating member is constituted of an insulating coat that is coated on the spring.

3. The ignition apparatus as set forth in claim 1 , wherein the insulating member is constituted of an insulating coat that is coated on the terminal extension portion.

4. The ignition apparatus as set forth in claim 1 , wherein the insulating member is constituted of an insulating spacer that is arranged between the outer circumferential surface of the terminal extension portion and the inner circumferential surface of the spring.

Assignees

• Denso Corp

Inventors

• Sugiura Akimitsu
• Hattori Kenji
• Takeda Shunichi
• Doi Kaori
• Wakasugi Ryota

Classifications

• F02P3/02

  having inductive energy storage, e.g. arrangements of induction coils {(ignition coils structurally combined with sparking plugs F02P13/00; constructional details of ignition coils H01F38/12)} · CPC title

• H01F38/12 Primary

  Ignition, e.g. for IC engines · CPC title

• H01T13/08

  Mounting, fixing or sealing of sparking plugs, e.g. in combustion chamber · CPC title

• F02P15/00

  Electric spark ignition having characteristics not provided for in, or of interest apart from, groups F02P1/00 - F02P13/00 {and combined with layout of ignition circuits (not combined F02B, F02C, F02G, F02K)} · CPC title

• H01T13/04

  Means providing electrical connection to sparking plugs · CPC title