Iver Johnson made tapered triangular cotterless cranks at a very early date, at least before 1930 and possibly well before. Just the right hand arm, as the left was integral with the axle. So as a patent attorney and as is very current in patent law, going from three sides to four is "obvious" so I doubt there was a patent issue, at least in the US.
Joe Bender-Zanoni Whitneyville, CT
-------------- Original message ----------------------
From: Wesley Gadd <wesleygadd@sbcglobal.net>
> Now that we seem to be entering the twilight of the reign of the taper squa
> re cotterless crank, I've been wondering about a couple of historical quest
> ions.
> First, did Stronglight originate the concept, and, if so, when? I'm guess
> ing late '30's? Did they hold a patent that kept other manufacturers from u
> sing this design? As far as I know, the first company to make a taper squar
> e crank after Stronglight was Campagnolo in 1958. Others used different met
> hods (Gnutti, T.A. "Criterium", Williams AB77 come to mind) but did the alm
> ost universal adoption of the taper square method have somthing to do with
> the expiration of a patent?
> I checked the archives but couldn't find much about this.
>
> Best regards,
> Wes Gadd
> Unionville,CT