Patent ID: 8840410

Claim:
A pop-up mechanism comprising: a board; a restricting unit formed on the board, and comprising a restricting sidewall and a bottom sidewall connecting the restricting sidewall; a pushing pillar slidably received in the restricting unit and resiliently connected to the bottom sidewall via a spring, the pushing pillar comprising a resilient engaging arm; and a return structure formed on the restricting sidewall and defining a positioning cutout therein; wherein the pushing pillar is urged by the spring and thereby held in an uppermost position in which a top of the resilient engaging arm is located above the return structure; when the pushing pillar is pressed downwards the resilient engaging arm elastically deforms and slides along the return structure and becomes engaged in the positioning cutout such that the pushing pillar is held in a lower position by the return structure with the spring being compressed; and when the pushing pillar is further pressed downwards the resilient engaging arm elastically deforms, slides along the return structure, and escapes from the positioning cutout with the spring being further compressed, whereupon the spring decompresses and drives the pushing pillar to move back up to the uppermost position at which the resilient engaging arm elastically returns to an original state.