Patent 10361027 was granted and assigned to Denso on July, 2019 by the United States Patent and Trademark Office.
A step-up transformer, an oscillator, and an ignition plug are comprised. The step-up transformer has a primary winding, a secondary winding, and a core. The ignition plug is connected to a first end of the secondary winding. A gap is formed in the core. The step up transformed is provided with a shielding part which is made of a conductive material and shields the magnetic flux leaking from the gap. A second end of the secondary winding is electrically connected to the shielding part.