Gas burner

A gas burner comprising:

• a head closed with a cap and formed of an outer part having a plurality of outer flame ports and an inner part spaced apart from the outer part and having a plurality of flame ports disposed at a central portion;
• an injector holder assembled to a top plate of a cooking appliance, having at least one portion disposed to be spaced apart from the head, including two or more first Venturi tubes horizontally disposed therein while spaced apart, and configured to fix a first injector through which a gas is introduced from the outside;
• an expansion chamber configured to communicate with one end of each of the two or more first Venturi tubes and communicate with an outer annular chamber of the outer part;
• an upright vertical channel of the expansion chamber that is configured to allow communication between the expansion chamber and the outer annular chamber;
• a second Venturi tube vertically disposed in the inner part of the head;
• and
• a second injector that is fixed to a center of an upper surface of the injector holder, spaced apart from the second Venturi tube to inject a gas into the second Venturi tube, positioned higher than the upper surface of the injector holder, and open,
• wherein the upright vertical channel is disposed to minimize a distance between the head and the expansion chamber, and increase an amount of primary air into the head by moving a gas-air mixture that passes through an outlet of each of the two or more first Venturi tubes and reaches the expansion chamber to the outer annular chamber of the outer part.