Patent ID: 9667037
Date: 2017-05-30
CPC Classifications: H01T

Claim:
1. A prechamber spark plug for a gas-powered internal combustion engine, comprising: a metallic body with a passage and an external thread located at a front end for screwing into the internal combustion engine; an insulator mounted in the passage of the body that projects out of the body at a back end facing away from the front end; a center conductor surrounded by the insulator that passes through the insulator and is connected in an electrically conductive manner to a center electrode projecting out of the front end of the insulator; a spark air gap formed between the center electrode and a ground electrode, which is connected in an electrically conductive manner to the body; a cap attached to the front end of the body that shields the center electrode and the ground electrode from a combustion chamber of the internal combustion engine after the prechamber spark plug is installed in the internal combustion engine, and that, together with the body, forms a prechamber in which the center electrode and the ground electrode are located; the cap has at least one opening that permits gas exchange between the prechamber and the space outside of the prechamber; the prechamber can be subdivided into a front part and a back part by an imaginary separating plane that is perpendicular to the center conductor at an end face of the center electrode that projects out of the insulator; the front part of the prechamber is located on a side of the separating plane facing the front end of the prechamber spark plug; the back part of the prechamber is located on a side of the separating plane facing the back end of the prechamber spark plug, is arranged inside the prechamber spark plug, and apart from its connection to the front part of the prechamber at the separating plane is closed in a gas-tight manner; wherein a volume of the back part of the prechamber is larger than a volume of the front part of the prechamber.