An exemplary ejection mechanism includes a first plate and a second plate opposite to the first plate, an ejector plate, ejectors, an actuator with a driving shaft, and a drive mechanism. The ejector plate and the drive mechanism are located between the first plate and the second plate. The ejection mechanism further defines first through holes which pass through the first plate and the second plate. The ejector plate defines a second through hole which is coaxial with the first through holes. The ejector extends from the ejecting plate to the first plate and aligns with the ejector hole of the first plate. The drive mechanism links with the driving shaft and the ejector plate, and the actuator drives the ejector plate between the first plate and the second plate via a drive mechanism, which makes the ejector eject or retract.