摘要 |
A key switch for a keyboard frame with a circuit board underneath includes a square-section key base, a key body sliding up and down in the key base, a key cap pressed into the key body, and a rubber cone between the key body and the circuit board. The cap includes a plunger with a downward-opening inner hole, whose lower rim contacts the upper side of the cone. The key base has four walls forming a square tube extending up from the keyboard frame surface. At the upper end of the walls are flanges extending in from the walls; each flange has a central flange notch, and between each pair of flanges is a 45-degree bevel extending across each of the base corners. The key body includes four stub rods that slide within the corners of the key base; each of the stub rods has an upper stop surface that limits the upward travel of the key body by abutting against the underside of a respective bevel. A central square through-hole in the key body is sized to accept the plunger of the key cap, and has four air passages along the corners of the through-hole to act as air bleeds. The air passages communicate with the inner hole of the key cap. A single projection on the key body can be aligned with one of the flange notches to orient the key cap.
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