Keyboard Patents

This is a list of patents describing mechanisms and features found on IBM and family keyboards, the designs of the keyboards themselves, the host systems that feature integrated keyboards and other interesting peripherals. Whilst information is summarised on this page, please note that the actual patents will likely be very technical. All photos used were from the patents themselves.

US3699296A: Catastrophically buckling compression column switch and actuator

This is the original buckling springs patent. It does not share a lot in common with the later applied mechanisms used on the Model Fs and Ms, but it describes three related mechanisms based around a spring located in a barrel, like the later designs.

GB1363777A: Toggle mechanism

This is the earliest patent available describing the IBM beam spring switch - the rest of world filing of US18358371A from 24 September 1971 (of which I am currently unable to locate). The components of the switch and the mechanism's assembly are described and several diagrams are given.

US4118611A: Buckling spring torsional snap actuator

Describes the IBM Model F's capacitive buckling springs switches, the applied form of Richard Hunter Harris' earlier patent regarding a similar design.

USD281246S: Keyboard

The ornamental design patent for the Model F-based IBM 104-key terminal keyboard (eg, P/Ns 1387033 and 6016730).

USD284009S: Keyboard panel

The ornamental design patent for the original IBM PCjr Cordless Keyboard (eg, P/N 8600032).

US4528431A: Rocking switch actuator for a low force membrane contact switch

Describes the IBM Model M's membrane buckling springs switches, an adaptation of Richard Hunter Harris' capacitive design for use with a membrane contact sheet.

USD289292S: Transportable computer

The ornamental design patent for the Model F-sporting IBM 5155 Portable Personal Computer.

USD290360S: Keyboard for a personal computer

The ornamental design patent for the Model F-based IBM Personal Computer AT Keyboard (eg, P/N 6450200).

USD288204S: Keyboard for a personal computer

The ornamental design patent for the revised IBM PCjr Cordless Keyboard (eg, P/N 6181835).

USD291806S: Multiple control element unit for data processing apparatus

The ornamental design patent for the IBM 6094-010 Dials.

USD284671S: Typewriter

The ornamental design patent for the Model M-sporting IBM Wheelwriter electronic typewriter.

USD292801S: Keyboard for a computer

The ornamental design patent for the square-shaped badge Model M-based IBM Enhanced Keyboard (eg, P/Ns 1388032 and 1390131).

USD299029S: Keyboard

The ornamental design patent for the IBM 4680-series 50-Key Modifiable Layout Keyboard.

USD308360S: Information entry keyboard or the like

The ornamental design patent for the IBM 104-key Quiet Touch terminal keyboard (eg, P/N 73X3832).

USD311913S: Keycap

The ornamental design patent for the windowed keycap design used on IBM 6094-020 type Lighted Program Function Keyboards.

USD308855S: Program function keyboard

The ornamental design patent for what seems to be an IBM 6094-020 type style Lighted Program Function Keyboard (LPFK).

USD330199S: Computer keyboard

The ornamental design patent for the Models M1 and M2 IBM Selectric Touch Keyboard and Lexmark Streamlined Keyboard (eg, P/Ns 1395300, 1398419 and 60G3570).

US5063289A: Combined mouse and trackball

The design of the original IBM TrackPoint device, which was a PS/2 mouse that could be turned over and used as a trackball device instead.

USD337106S: Auxiliary keypad

The ornamental design patent for the Model M3 IBM Numeric Keypad for IBM PS/2 L40SX (eg, P/N 1396199).

US5521596A: Analog input device located in the primary typing area of a keyboard

The original TrackPoint-spawning patent that describes both a pointing stick device and an under-keycap mounted device that can make use of strain gauges or various other alternative technologies for sensing movement with a pointing stick.

USD339112S: Portable computer housing

The ornamental design patent for the Model M3-sporting IBM Personal System/2 L40SX portable computer.

US5570111A: Graphical user interface cursor positioning device having a negative inertia transfer function

Describes the formula used for implementing the "negative inertia" feature found in TrackPoint III and IV pointing sticks. Negative inertia counteracts the feeling of sluggishness (ie, having inertia) via acceleration and is implemented in the TrackPoint module's firmware and thus applied before the data for cursor movement reaches the host PC.

US6642857B1: Capacitive pointing stick

Describes the force-sensing capacitor (FSC) technology behind the Synaptics TouchStyk pointing stick. The TouchStyk is competing technology against IBM/Lenovo TrackPoint that found its way into several IBM integrated pointing device and UltraNav keyboards (the SK-8835/8840/8845 family).