I presume that you are referring to the Shimano Dyna-Drive (DD) mechanism as featured in the early 1980's Dura-Ace EX series:
Robert "Let Your Fingers Do The Walking Through The Velo-Pages" Broderick
...the "Chronically Cloudy Clime" of Oregon
> From: firstname.lastname@example.org
> To: email@example.com
> Date: Tue, 16 Feb 2010 17:24:35 -0800
> Subject: [CR] Dura Ace Crank/Pedal Question
> I'm sure this is covered in the archives, but I need a search string hint as
> I'm striking out. I'm looking for more information on a vintage Dura Ace
> crankset with matching pedals where the pedal bearing is in the crank arm.
> The pedal mounting hole is more or less 3/4" diameter and seems to house the
> bearing assembly. The pedals look "trackish" and very light, but the crank
> appears pretty robust as does the threaded mount.
> Steve Gray
> Las Vegas, NV USA