Mold locking oil cylinder, mold locking mechanism and injection molding machine

The utility model discloses a mould locking oil cylinder, a mould locking mechanism and an injection molding machine, the mould locking oil cylinder is used for providing driving force for the mould locking mechanism of the injection molding machine, the mould locking mechanism comprises a tail plate, the tail plate is provided with an oil cavity with an opening at one end, and the bottom of the oil cavity is provided with a communicating hole. The mold locking oil cylinder comprises a cylinder barrel, a piston, an annular gland and a sealing piece, and the cylinder barrel is fixed to the tail plate and communicated with the oil cavity through the communicating hole. The piston is installed in the oil cavity and reciprocates in the axial direction of the oil cavity. An annular gland is located at the opening and arranged between the piston and the tail plate in a sleeved mode, and a shaft sleeve is installed on the inner ring face of the annular gland. The sealing piece is arranged between the piston and the