Governing w the Off-center Wheel

[babraid]

Does anyone know who came up with the idea of governing a windmill's speed by having an off-center wheel and a governor spring?
The description in the Field Guide of Perry's development of the Pumping Aermotor says that it used no truly innovative features in governing (pg 38).
Thanks in advance for any input

[Ron Stauffer]

Halladay's design.varied the pitch of the blades to govern so it wasn't off center.

Dempster was early if not first to be off center

Original Dempster Solid Wheel Windmill (1885-1909)

The first windmill manufactured by the Dempster Mill Manufacturing Company was the Dempster Solid Wheel. It was a wooden wheel windmill produced in ten and twelve-foot diameter sizes. The vane sheets were one of the most decoratively painted of any windmill produced in North America.

The Original Dempster Solid Wheel mill represents a very early example of a “pull-in” style of mill. The windmill turns on when a control wire is attached to a three-foot coiled governor spring. As wind speeds increase, the off-center wheel tends to turn away from the wind toward the vane. This action is counterbalanced by the tension of the governor spring. The spring pulls the wheel back to face the wind when the velocities decrease.

Ron Stauffer
Montrose CO

[Windcatcher530 Dan]

My wood Stover has a offset governing and is controlled by a governor weight. It was manufactured in1876 not sure if it was the first but very early.

[Wayne]

Thanks for the info fellas!

[mtblah]

Thanks guys , didn’t know that

[babraid]

Thanks Ron and Dan, both of those pieces of info were very helpful

[Challenge 27]

Perhaps the first windmill to utilize the "off-center wheel" concept was the Perkins Solid Wheel. Perkins patented his windmill in 1869. Just when the first ones were made is uncertain. In 1873 he and his brother founded the "Perkins Windmill and Axe Company." But Perkins had been making windmills before then. See the Field Guide pages 284-285, 368, 410. Perkins designed his windmill so that the vane would tip up as his windmill turned out of the wind, using the weight of the vane as the source of resistance to the tendency of the off-center wheel to turn out of the wind; probably the first to do so.

Ron Stauffer correctly stated that Dempster was probably the first to use a coiled governor spring as part of the governing system. In this windmill,
the spring was located at the base of the tower.

Perry might very well have been the first to connect one end of a coiled governor to the vane and the other end to the main casting; replacing the then-popular weighted lever as the source of resistance to the tendency of the off-center wheel to turn out of the wind. As so often happens in the history of mechanical invention, the idea was copied by others.

Challenge 27

P.S. Notice in the history of the American windmill how few truly innovative ideas (such as Reverend Wheeler's Eclipse, or Perry's wheel) there are. But there was a very strong tendency to "follow the leader" (meaning the windmills that were selling well). Many designers shamelessly copied others' innovations, sometimes "tweaking" them just enough to avoid being used for patent infringement. And do not forget Rufus Marcy's Red Star/Red Cross windmills! See the Field Guide pages 272-273.

P.P.S. Another idea that was often copied was Perkins idea of the tip-up vane.

[babraid]

Thanks Challenge 27, more food for thought