A retraction device includes a spindle movable along the axis thereof and an operating unit including a pull rod and a movable member. The movable member defines a step-shaped groove, the pull rod has a first end connected to the spindle, and a second end received in the groove; the groove includes a first step and a second step and an inclined face connecting the first step and the second step arranged along a first direction, and a height of the second step is greater than that of the first step along the axis direction of the spindle; the movable member is slidable along the first direction relative to the pull rod, to allow the spindle to switch between a retraction position in which the pull rod is received in the second step, and a release position in which the pull rod is received in the first step.