先接后断触点

[电] make-before-break contact

xiān jiē hoù duàn chù diǎn ㄒㄧㄢ ㄐㄧㄝ ㄏㄡˋ ㄉㄨㄢˋ ㄔㄨˋ ㄉㄧㄢˇ