Residual liquid backflow filling device

The utility model discloses a raffinate backflow filling device, which relates to the technical field of filling, and comprises a storage tank, a negative pressure pump and a booster pump, one side of the bottom end of the storage tank is provided with a connecting valve, the bottom end of the connecting valve is provided with a connector, a filling bottle is arranged below the connector, and the negative pressure pump is connected with the booster pump. And a mounting groove is formed in the side, away from the connector, of the bottom end of the storage tank, a negative pressure pump is mounted at the top end of the interior of the mounting groove, a negative pressure pipe is mounted at the output end of the negative pressure pump, a mounting column is mounted on one side of the bottom end of the interior of the storage tank, a cavity is formed in the top end of the mounting column, and a fixing spring is mounted at the bottom end of the interior of the cavity. Suction force is generated for liquid in the f