Spark plug, cylinder cover and engine

Abstract

The invention relates to a spark plug, a central electrode is at least partially arranged in an inner hole of an insulator, one end of a grounding electrode is attached to a shell, and the other end of the grounding electrode radially extends beyond an ignition end of the central electrode and extends to the position below an axial end of the shell to define an axial gap D axial with the axial end of the shell. Thus, the gap between the central electrode and the grounding electrode can be limited after the grounding electrode is welded to the shell, the gap between the grounding electrode and the central electrode is prevented from being too small, the ignition stability is improved, fire is avoided, the reliability of the spark plug is improved, and the service life of the spark plug is prolonged. And when special combustion conditions occur in the cylinder, the stress of the grounding electrode is increased, the grounding electrode is bent outwards, and the other end of the grounding electrode can radially abut against the axial end part of the shell, so that the situation that the ignition gap is enlarged due to the fact that the grounding electrode is excessively bent outwards is prevented, and the problems that the ignition stability of an engine becomes poor due to the fact that the ignition gap is enlarged and the fire is caused when the condition is serious are avoided.

Description

technical field [0001] The invention relates to the technical field of automobile engine systems, in particular to a spark plug, a cylinder head and an engine. Background technique [0002] With the continuous reform of the national energy policy, especially the proposal and upgrade of the new energy development strategy, as well as the increasingly stringent regulations on fuel consumption and emission of automobiles, cleaner emission levels and higher combustion thermal efficiency are inevitable requirements for technological upgrading, and are also The core point of technological competition among automobile companies. At present, for existing natural gas engines, once the combustion conditions of the engine change, the combustion temperature rises, or the number and degree of cold and heat shocks increase, the ignition performance of the engine will decrease, and in severe cases, it will misfire, which will lead to carbon deposition, poor combustion, and increased fuel c...

AI Technical Summary

Problems solved by technology

[0003] Based on this, it is necessary to provide a spark plug that can solve the problem of engine ignition performance degradation and even misfire caused by the change of the ignition gap of the spark plug.

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