Combined core drill for improving core-drilling effect of fractured stratum

The utility model relates to a combined core drill for improving the core-drilling effect of a fractured stratum. The core drill comprises a shaft bottom motor, an impactor, a half-closed tube core drilling tool and a bottom spray core-drilling bit, and is characterized in that the lower end of a driving shaft of the shaft bottom motor is connected with the upper end of the impactor; the lower end of the impactor is connected with the upper end of the half-closed tube core drilling tool; the lower end of the half-closed tube core drilling tool is connected with the bottom spray core-drilling bit; the shaft bottom motor is in transmission connection with the half-combined tube core drilling tool and the bottom spray core drilling bit; and the impactor is used for providing impact force for the half-closed tube core drilling tool and providing vibrating force for the bottom spray core drilling bit. Due to the adoption of the combined core drill, the roundtrip core drilling length and mechanism drilling speed ca