Ignition system

Patent metadata

Field	Value
Publication number	US-9488151-B2
Application number	US-201213722453-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Feb 8, 2012
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

An ignition system is provided, in which a Zener diode is connected in parallel with a spark plug, to suppress torque variation from becoming large in an engine when deterioration of the spark plug is advanced. Specifically, the ignition system includes a secondary coil having an end connected to a center electrode of the spark plug via a connecting path. The connecting path is connected to a constant-voltage path having a grounded end and including the Zener diode. The time from when an ignition signal is switched off until when ignition timing occurs is measured for a plurality of times. The difference between a maximum value and a minimum value among the plurality of measurements is defined to be a variation range. A breakdown voltage of the Zener diode is adjusted based on requirements such as for rendering the variation range to be a predetermined time or smaller.

First claim

What is claimed is:

1. An ignition system comprising:
a spark coil having a primary coil and a secondary coil which are magnetically connected to each other;
a spark plug having a center electrode and a ground electrode, both electrodes being projected into a combustion chamber of an internal combustion engine and forming a gap between both of the electrode; and
an ignition control means that produces discharge sparks in the gap between the center electrode and the ground elec…

Assignees

• Denso Corp

Inventors

• Shibata Masamichi
• Mizutani Atsuya
• Hattori Koichi
• Imanaka Yasuomi

Classifications

• F02P3/0407

  Mechanical Engineering · mapped topic

• H01T13/44

  Electricity · mapped topic

• F02P3/0552

  Mechanical Engineering · mapped topic

• F02P3/02

  Mechanical Engineering · mapped topic

• F02P1/083 Primary

  Mechanical Engineering · mapped topic