Keyboard device

A keyboard device comprising:

• a substrate having a top surface and a bottom surface opposite to the top surface, wherein the substrate comprises a welding-fixing portion, the welding-fixing portion comprises a through hole and an arch-shaped bridge member, the through hole is defined through the top surface and the bottom surface, the arch-shaped bridge member is connected in the through hole, the arch-shaped bridge member divides the through hole into a plurality of partition holes, the arch-shaped bridge member has an arch portion and a plurality of bridge bases extending from the arch portion, the bridge bases are connected to an edge portion of the through hole, and the arch portion protrudes from the top surface to form a recessed portion;
• a plurality of keycaps disposed on the top surface of the substrate;
• and
• a frame disposed on the top surface of the substrate, wherein the frame comprises a plurality of hollow holes respectively corresponding to the keycaps, the frame comprises a welding member, the welding member comprises a plurality of welding posts and a welding-fixing base connected to end portions of the welding posts, the frame is leaned on the arch portion, the welding posts respectively pass through spaces between the edge portion of the through hole and the arch-shaped bridge member, the welding posts respectively correspond to the partition holes, the end portions of the welding posts are hot-welded and solidified to form the welding-fixing base, and the welding-fixing base is received and fixed in the through hole and the recessed portion.