Editing Buckling spring (section)

{{Short description|Mechanical switch mechanism}}
{{More citations needed|date=March 2023}}
[[File:Unicomp space saver model m. with removed key 3864555240 9a2c6b95da o.jpg|thumb|upright|[[Unicomp]] Model M with removed z key. The exposed buckling spring is visible.]]

A '''buckling spring''' is a type of keyswitch [[Mechanism (technology)|mechanism]], popularized by [[IBM]]'s [[Keyboard technology|keyboards]] for the [[IBM PC|PC]], PC/AT, 5250/3270 terminals, PS/2, and other systems. It was used by IBM's [[Model F keyboard]]s (for instance the [[AT keyboard]]), and the more common [[Model M keyboard|Model M]]. It is described in {{US patent|4118611}} (Model F) and {{US patent|4528431}} (Model M), both now expired. According to the original patent: "A non-teasible, snap action, tactile feedback, key mechanism of extreme mechanical simplicity and high reliability is achieved."<ref>{{Cite patent|number=US4118611A|title=Buckling spring torsional snap actuator|gdate=1978-10-03|invent1=Harris|inventor1-first=Richard Hunter|url=https://patents.google.com/patent/US4118611/en}}</ref>