Abstract: A retractable headphone connection structure includes two connection supports which are slidably connected with each other in a sliding connection direction. One of the connection supports has a plurality of first magnetically attractive portions arranged at intervals along the sliding connection direction. The other of the connection supports has a second magnetically attractive portion. Therein, the two supports relatively slide to make the second magnetically attractive portion slide over the plurality of first magnetically attractive portions to generate a magnetic attraction force between the second magnetically attractive portion and one of the first magnetically attractive portions that is opposite to the second magnetically attractive portion. The magnetic attraction force positions the first connection support and the second connection support. A head-mounted audio device includes a headphone and the above retractable headphone connection structure.

Abstract: A keyswitch structure includes a base plate, a keycap, and a support mechanism. The support mechanism supports the keycap above the base plate. An outer support of the support mechanism includes a reinforcing body and a connecting structure fixed on the reinforcing body. The outer support is connected to the base plate and the keycap through the connecting structure. In an embodiment, the reinforcing body has two openings. Two inner supports of the support mechanism are pivotally connected to the connecting structure and are located in the two openings, respectively. In another embodiment, the reinforcing body as a whole extends along a plane. The reinforcing body has a bent fringe, which is inserted into the connecting structure and is not perpendicular to the plane.