Abstract: A transmission component acting as a safety device in a printer for the safety of a print operator includes a gear portion, a transmission shaft, and a resilient member. One end of the gear portion defines a receiving space, the transmission component and the resilient member are received in the receiving space. The resilient member bears against the bottom end of the receiving space and the transmission shaft. The resilient member is elastically deformed to slide in the receiving space if operator or limb of operator is detected during loading procedure.