Clevis joints

Hi,
anyone knows about/uses clevis joints on their deltas? Weiss uses them on some delta robots. And so do some of the Chinese delta pick and place robot manufacturers. Cost of a custom solution aside what's the downside of these?

These joints are sometimes called gimbal joints or perhaps Spicer joints though I think that variation has another name that slips my mind. The joint itself consists of the clevis joint and the bearing that the clevis fork is mounted on
Gimbal joints were used on the earliest Delta printer such as the Rostock, but were rapidly replaced by ball joints of various sorts - including the magnetic joints common now.
I think that gimbal joints have more play and some geometric errors that ball joints do not have, but are preferred in things where the acceleration can be quite large. In a 3D printer, most of the movements are during printing and the speed and acceleration are constrained by how fast plastic can be laid down. Conversely, in a pick-and-place machine, most of the time is spent moving from the supply of parts to the destination so higher speeds and accelerations are desirable.
Video of a Rostock from 10 years ago with the "Spicer joints" clearly visible [www.youtube.com]

Thanks.

And the joints on the Tractus3D printers? How are these called? The ones with the stud mated to the rod end.
Are these custom made?

Usually called rod end bearings although the names rose bearing, rose joint, ball end joint or spherical plain bearing are all used.
There are a lot of variation in construction, some with a hole in the bearing, some with a stud sticking out. I like the plastic rod end bearings from IGUS as they have a long service life with minimal maintenance.

Mike

I have a few samples of the IGUS bearings at hand and don't like them very much. Both the KARM-06-CL and the KARM-08-CL samples I have are too stiff.