IBM Wheelwriter/Sources

Patents

Most of these have expired by now, 20 years after invention.

IBM Hardware

• US5000592 - Envelope addressing format feature for electronic typewriters

IBM Software

• US4799811 - Automatic relocate on continuation of document playout
• US4894798 - Automatic stop code insertion feature for a word processing apparatus
• US4957380 - Tab adjust function for an electronic typewriter to permit the shifting of tabs from a first to a second format

Lexmark

• US5038279 - Direct hot-keying with reset of printer parameters for a secondary application including a typewriter emulator

Other Manufacturers

• US4842428 - Electronic typewriter with spell checking and correction: Brother
• US3924722 - Typewriter with electronic keyboard: Cpt Corp

Manuals

• Lexmark - Official Product Manuals for IBM/Lexmark Wheelwriter Typewriters
• IBM - Typewriter History Milestones, after 1970