A novel cup device comprises a plug and an electric connecting base, a tightly-inserting arm is fixedly arranged at the lower end of the plug, a tapering part and a pointed part located at the lower end of the tapering part are arranged at the lower end of the tightly-inserting arm, and locking grooves extending left and right are formed in the pointed part; a sliding cavity is formed in the electric connecting base, upper sliding grooves are formed in the top wall of the sliding cavity in a bilateral symmetry mode, a tightly-inserting groove communicated with the outer end is formed in the top wall of the upper sliding groove, a sliding block is installed in the sliding cavity in a vertically sliding mode, sliding arms are arranged at the upper end of the sliding block in a bilateral symmetry mode and installed in the upper sliding grooves in a sliding mode, tapering grooves are formed in the sliding arms, through grooves communicated with the tapering grooves are formed in the sliding block in a bilateral symmetry mode, the electric connecting base is arranged at the lower end of the sliding block, a lower sliding groove is formed in the position, below the electric connecting block, of the bottom wall of the sliding groove, and a sliding plate is installed in the lower sliding groove in a vertically sliding mode.