Carburetor for an internal combustion engine

A carburetor for an internal combustion engine of a portable handheld work apparatus, the carburetor comprising:

• a carburetor housing having an air-intake channel therein through which air flows to the engine;
• said air-intake channel defining a venturi section;
• a throttle flap assembly including a throttle flap pivotally mounted in said air-intake channel so as to be movable to positions including an idle position and a start position for allowing respectively different quantities of air to flow to the engine;
• a control chamber for holding fuel;
• a main fuel channel connecting said control chamber to said air-intake channel;
• an idle fuel channel also connecting said control chamber to said air-intake channel;
• an ancillary channel connecting said control chamber to said air-intake channel;
• a valve unit arranged in said ancillary channel;
• said valve unit including a valve closing element movable between a first position wherein said ancillary channel is blocked and a second position wherein said ancillary channel is clear so that fuel can flow therethrough and into said air-intake channel;
• and,
• coupling means for coupling said valve closing element to said throttle flap so as to displace said throttle flap out of said idle position to assume said start position when said valve closing element is moved to said second position thereby changing the quantity of air flowing through said air-intake channel.