Pay-off and take-up device for overhead line system

The utility model relates to the technical field of electrified railway construction, in particular to a pay-off and take-up device for an overhead line system, and aims to solve the problem that an existing device cannot be suitable for center shafts with different diameters. The device comprises a take-up and pay-off mechanism and a walking mechanism, the take-up and pay-off mechanism is installed on the walking mechanism and comprises a winch installation assembly and a bearing assembly, and the winch installation assembly comprises a middle shaft; the bearing assembly comprises two bearing rollers, and the two bearing rollers are arranged below the middle shaft and are in rolling contact with the middle shaft to bear the middle shaft; the two bearing assemblies are arranged at the two ends of the middle shaft correspondingly and are the first bearing assembly and the second bearing assembly correspondingly. And the middle shaft is placed on the bearing roller, so that the middle shaft can be quickly repla