Abstract: A mounting base structure for a swingable arm which is placed in an appropriate position of a wall sconce lamp, an upper and a lower securing adapters are used with a connecting member to pivotally connect the mounting base to a swingable arm. By inserting and fitting the square aperture of the adapter at one end of the swingable arm to a corresponding connecting body of a connecting member together, the assembly can be swung synchronously. By applying extrusion and stretching on both ends of the connecting body, the upper and the lower securing adapters can be integrated with the adapter on the swingable arm into a one-piece structure, preventing the electrical wiring from tangling and the swinging movement of the arm is secured and stable.

Abstract: A swing arm is disclosed including a bottom curved tube, which has a first fitting with an inward bottom staking step and a second fitting with an inside chamber respectively at two opposite ends, a top straight tube, which has a first fitting with an inward bottom staking step and a second fitting with an external stop knob respectively formed at two opposite ends, and a connecting device to connect the first fitting of the top straight tube to the first fitting of the bottom curved tube through a hollow T-shaped rivet joint for permitting the top straight tube to be turned on the bottom curved tube for engaging the external stop knob of the second fitting of the top straight tube into or disconnecting it from the chamber of the second fitting of the bottom curved tube, a first washer retained between one head of the hollow rivet and one bottom staking step, a second washer retained between the other head of the hollow rivet and the other bottom staking step, and two friction washers retained between the sta