Heating device, and atomizing head, atomizer and electronic cigarette having the same

An atomizing head of an electronic cigarette comprising:

• a mounting base having a sleeve shape;
• a cover provided on one end of the mounting base;
• a heating device provided inside the mounting base, the heating device comprising:
• a sleeve-shaped heating element having a spiral-shaped heating wire;
• and
• a liquid absorbing component disposed around an outer surface of the heating element, wherein the liquid absorbing component is formed by at least two curved liquid absorbing elements engaging each other to form a sleeve that wraps around the outer surface of the heating element,
• wherein a spiral groove is provided in an inner surface of the liquid absorbing component and the spiral-shaped heating wire engages the spiral groove;
• and
• a seal component provided between the cover and the liquid absorbing component,
• wherein the mounting base is provided with an inlet passage on a side wall thereof for guiding tobacco liquid from the electronic cigarette to the liquid absorbing component,
• wherein a positioning element for fastening the liquid absorbing component is provided between the mounting base and the heating device and encompasses the liquid absorbing component and an inner surface of the positioning element is substantially entirely and directly in contact with an outer surface of the liquid absorbing component, and
• wherein the seal component is in direct contact with the mounting base and the liquid absorbing component and prevents the tobacco liquid from flowing from the mounting base and/or the liquid absorbing component to the cover.