An embodiment provides a control method capable of controlling a switching-mode power supply to provide an output power source. A threaded tap formed of hardened steel is positioned and disposed on the head for forced, threaded engagement with the threads of the PVC pipe or fitting. Herein, the protruding ends of the insulating coil are partially removed by physical force to expose the metal core and the external electrodes are electrically connected to the exposed metal core. A closing member having a sealing material is provided at a side portion of one door panel with a high movement speed, and only during door closing, the closing member is brought into contact with a side portion of the other door panel to close a gap between the side portions.