Patent US 3187118A

Patent number	US 3187118A
Title	Electrical switch having means for interconnecting concentric switch shafts
Inventors	Marlow Butler, Oz Svehaug
Company	Tektronix Inc
Filing date	1962-01-18
Grant date	1965-06-01
Cites

See e.g. 11B2, 1A5 and many others.