Case cover detecting device for case sealer

The utility model discloses a case cover detecting device for a case sealer. The case cover detecting device comprises an expansion support, a reflecting optoelectronic switch detector and a PLC system of the case sealer, wherein the expansion support is fixed to the position above an auxiliary material frame, the reflecting optoelectronic switch detector is fixed to the expansion support and corresponds to a position identifying block on a case cover unfolded on the auxiliary material frame, and the PLC system of the case sealer is connected with the reflecting optoelectronic switch detector and further connected with an alarming device and a removing device. According to the case cover detecting device for the case sealer, the reflecting optoelectronic switch detector is additionally arranged to detect the position identifying block on the case cover, the arrangement direction of the case cover is judged through the PLC system of the case sealer, and if a reverse case cover is detected, alarming and removing are conducted through the alarming device and the removing device, so that defective products are prevented from entering the market. By means of the alarming and automatic removing mode, halt cannot be caused in the production process, and an upstream machine cannot be influenced. Defective cigarette cases are removed in time, so that cigarette bars cannot be damaged at the sealed positions of the cigarette cases and can be put into production again.