Premixer and gas device

A premixer, comprising:

• a premixer body provided with a gas channel and a gas distribution chamber provided in the gas channel;
• an adjustment shaft rotatably passing through the gas distribution chamber;
• and
• a gas regulator provided at a portion of an outer peripheral wall of the adjustment shaft and having an arc-shaped outer wall surface adapted to the inner wall of the gas distribution chamber, wherein:
• the gas distribution chamber has a cylindrical inner wall,
• a side wall of the gas distribution chamber is provided with a first gas distribution hole, a second gas distribution hole, a third gas distribution hole, a fourth gas distribution hole,
• a gas inlet hole, the first, second, and third gas distribution holes are spaced from each other,
• the third gas distribution hole is spaced from the fourth gas distribution hole, and a pattern formed by the first gas distribution hole is non-congruent with a pattern formed by the second gas distribution hole;
• when the gas regulator rotates within a first angle range,
• the second gas distribution hole is blocked;
• the third gas distribution hole and the fourth gas distribution hole are completely unblocked;
• and
• the gas regulator is capable of rotating to adjust a gas flow area of the first gas distribution hole to regulate an amount of gas flowing through the first gas distribution hole;
• and
• when the gas regulator rotates within a second angle range,
• the first gas distribution hole and the fourth gas distribution hole are blocked;
• the third gas distribution hole is completely unblocked;
• and
• the gas regulator is capable of rotating to adjust a gas flow area of the second gas distribution hole to regulate an amount of gas flowing through the second gas distribution hole.