Peaucellier-Lipkin linkage - GIF

[Floradawg]

Probably not likely, it was invented in the 1860's. As for applications, a bit of info here (as much as I hate to quote wikipedia):

"Until this invention, no planar method existed of converting exact straight-line motion to circular motion, without reference guideways. In 1864, all power came from steam engines, which had a piston moving in a straight-line up and down a cylinder. This piston needed to keep a good seal with the cylinder in order to retain the driving medium, and not lose energy efficiency due to leaks. The piston does this by remaining perpendicular to the axis of the cylinder, retaining its straight-line motion. Converting the straight-line motion of the piston into circular motion was of critical importance. Most, if not all, applications of these steam engines, were rotary.

The mathematics of the Peaucellier–Lipkin linkage is directly related to the inversion of a circle."

Most of these linkages were (I expect still are) developed as mathematical problems to be worked on and solved either to solve some particular real world problem or just for the sake of understanding the minute details of the world more deeply. Eventually lots of them trickle down into real world use. I don't pretend to understand much of the esoteric analysis behind stuff like this but find it all fascinating nonetheless. I have read a few books on the study of linkages and while I feel like I can follow much of what is being explained, the understanding leaves me pretty soon after I read it.


https://en.wikipedia.org/wiki/Peauce...Lipkin_linkage

I'm not disagreeing with you but there's a much simpler way to do it. Think of a steam locomotive. If you spin the drive wheel the piston rod will make a nice linear move.

[mklotz]

I'm not disagreeing with you but there's a much simpler way to do it. Think of a steam locomotive. If you spin the drive wheel the piston rod will make a nice linear move.

Yes the piston rod moves linearly. However, it drives a slider in the crosshead which also moves linearly. The link driving the rotating wheels connects to the slider, not the piston rod. The forces perpendicular to the motion of the piston are absorbed by the slider pushing against the crosshead. There is essentially no perpendicular force on the piston rod.

It was the invention of the crosshead that allowed the piston to drive the crankshaft/loco wheel directly that eliminated the need for the overhead beam and the various linkages, Peaucellier included.

[clavius]

I'm not disagreeing with you but there's a much simpler way to do it. Think of a steam locomotive. If you spin the drive wheel the piston rod will make a nice linear move.

I do get what you are saying. I think the point in this instance is what is noted in the description: "converting exact straight-line motion to circular motion,without reference guideways.

I think it's the lack of reference guideways that was the important point of this particular linkage, for an application like the beam engine that Marv K. posted.

To your point, there is are much simpler ways to do this, but until crossheads came along this was one workable (if more complex) way to accomplish that conversion.