Large-locking-force rod type oil well pump

The utility model relates to an oil exploitation device, in particular to a large-locking-force rod type oil well pump. Comprising a pull rod, a guide sleeve, a pump cylinder assembly, a sealing device, an outer pipe, an outer pipe lower joint, a liquid outlet joint, a plunger, a fixed valve cover, a fixed valve group, a fixed valve lower joint and a locking device, the lower end of the pull rod is connected with a liquid outlet connector, the lower end of the liquid outlet connector is connected with a plunger, the lower end of the plunger is connected with a fixed valve group, the fixed valve group is arranged in a fixed valve cover, and the lower end of the fixed valve group is connected with a fixed valve lower connector; the guide sleeve is fixed on the outer wall of the pull rod; the pump cylinder assembly is sleeved with the outer pipe, the lower end of the outer pipe is connected with the first outer pipe lower connector, the first outer pipe lower connector is connected with the locking device, and t