Precombustion chamber igniter and cold start control method for methanol engine

A precombustion chamber igniter, comprising a housing, a fuel injector (3), a spark plug (5), and an electric glow plug (4), wherein the fuel injector (3), the spark plug (5) and the electric glow plug (4) are arranged in the housing, and a nozzle of the fuel injector (3) and an electrode of the spark plug (5) extend into an injection chamber (6);

• the fuel injector (3) is configured to inject fuel into the injection chamber (6) to form a target gas mixture;
• a bottom of the housing is provided with a plurality of jet holes (1) and a first through hole in a penetrating manner, and the jet holes (1) are arranged around the first through hole;
• the electric glow plug (4) comprises a retractable device and a heating segment (7) located at a lower part of the electric glow plug, the heating segment (7) is able to have two working positions under a control of the retractable device, which are a first position and a second position;
• at the first position, the heating segment (7) is wholly located in the injection chamber to provide heat energy for the injection chamber (6), and at the second position, the heating segment is partially located in the injection chamber and passes through the first through hole, while a rest of the heating segment is located in a main combustion chamber of an engine, to provide heat energy for both the injection chamber (6) and the main combustion chamber;
• and a sidewall profile of the heating segment (7) is in fit with a profile of the first through hole.