1. A shielding cover mounting and dismounting apparatus for mounting or dismounting a lower shielding cover connected with a circuit board, the circuit board having an upper surface and a lower surface, the lower shielding cover being connected with the lower surface, the shielding cover mounting and dismounting apparatus comprising:a base;
a first supporting seat disposed on the base, the first supporting seat has a bearing cavity, the lower shielding cover and the circuit board are disposed in the bearing cavity, and the lower shielding cover is disposed between the circuit board and a bottom surface of the bearing cavity;
a second supporting seat including a second elastic member, the second supporting seat is disposed in an opening of the bearing cavity, the second elastic member supports the second supporting seat on the base, whereby the second supporting seat can move relative to the first supporting seat in the opening of the bearing cavity via the second elastic member, wherein a position of the second supporting seat corresponds to the lower shielding cover to support the circuit board in the bearing cavity;
a heater disposed at one side of the upper surface of the circuit board disposed in the bearing cavity, the heater is movably abutted on the upper surface of the circuit board to heat the lower shielding cover connected on the lower surface of the circuit board whereby the lower shielding cover is capable of being dismounted from the circuit board; and
a moving seat including a plurality of third elastic members, the third elastic members connect the moving seat to the heater, the moving seat drives the heater to move closer to or away from the circuit board.