By Staff
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Figure 1 is a view of the machine from the side.
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Side view of the Yocker's Threshing Machine.
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Figure 3 is a longitudinal section.

Route 1, Assaria, Kansas 67416

When one looks at the magnificent machines and implements the
American farmer uses today, he cannot help but think that there
must have been some geniuses to create and design this equipment.
Obviously, these men were the engineer graduates of universities,
now working for implement companies in huge laboratories and test
fields. Well, this may be especially true of developments in
agriculture technology during the last fifty years or so. But in
looking over the past two hundred years, the American farmer has
done more to better his lot by inventions, than all of the college
educated agricultural engineers have ever created. Cyrus McCormick
and his reaper, the Pitts Brothers and their thrashing machine, the
Marsh Brothers and their special wheat binder, were all farmers and
came up with some of the more notable inventions. But many farmers
have come up with ideas and devices over the years. Many of these
ideas were never heard of by outsiders, sometimes just helping the
farmer with his own work, others important enough to be patented,
adding to the development of various machines which make up
important agricultural machines of today.

I have been lucky enough to meet up with one of these
inventor-farmers and have procured his invention. His name is Ralph
E. C. Yockers of Smolan, Kansas, and his brain-child is a sorghum
threshing machine. It all began one fall about 1920. Mr. Yockers
had bundled and shocked his sorghum crop and decided to have it
thrashed, because he needed the grain. Note – the sorghum raised
during this time was only of the tall variety such as cane, Kafir
corn, Siberian wheat, and Sudan grass. Short sorghum, milo,
wasn’t around until the middle 1930’s, when it became
popular. So Mr. Yockers hired a thresherman to thrash the crop, but
the results were disasterous. As expected, the cane stalks came out
chopped and mangled and would have to be fed loose. But what really
peeved Mr. Yockers was that the grain came out cracked and smashed.
The thrasherman made adjustments on his machine, but the results
were still the same.

Mr. Yockers, being a young enterprising man of about twenty-five
years, thought surely he could come up with a better way to thresh
sorghum. He schemed and planned, finally devising a machine that
would thresh sorghum without the need to top it and would not crack
the grain. About 1922 a machine was built that worked so well that
a second machine was built about a year later. Equal success with a
second machine prompted Mr. Yockers to think that he had invented
something new and different. So he filed for a patent on December
30, 1925, and after a couple of years, he was awarded patent no.
1702146 on February 12, 1929, for a new and useful improvement in
sorghum-threshing machines. But unfortunately, small combines had
been in use for a couple of years and milo was being introduced at
this time. As a result, there was no demand for an invention of
this kind, so the patent was never sold.

Well, even though Mr. Yockers wasn’t able to sell his
invention, it was a financial success. In case you haven’t
figured it out by looking at the pictures, here is how the
contraption works. At the back, the end opposite the engine is a 28
inch threshing-machine cylinder. One grabs a bundle of cane and
inserts the end with the heads into the cylinder, inserting no more
than the heads. The bundle is rotated once or twice, whatever it
takes to knock off all of the grain in the bundle. Then the bundle
is pulled out and another one inserted. The grain and pieces of
heads removed by the cylinder are then elevated into a cleaning
section which separates the chaff and grain. So after threshing,
one is left with both grain and intact bundles which can be shocked
again and later fed as fodder. The farmers in the area liked the
arrangement and for the next twenty-five years or so, Mr. Yockers
custom threshed sorghum all over Saline County, the eastern part of
Ellsworth County, the southern parts of Lincoln and Ottawa
Counties, and made himself quite a

Mr. Yockers used his two original machines and never built any
more. One machine was kept at his farm which he threshed with in
the area, and the other was kept at Beverly, Kansas where an
employer of Mr. Yockers cared for the machine and threshed for
farmers in that area.

Figure 2 is a detailed drawing showing the means for vibrating
the frame with the screens, being operated from a crank when on the
fan shaft.


1.  Hinged door
2.  Rotary cylinder
3.  Concaves
4.  Conveyor chain
5.  Deflector
6.  Top screen
7.  Middle screen
8.  Bottom screen
9.  Fan
10.  Crank wheel on fan shaft
11.  Connecting rod
12.  Link
13.  Element
14.  Housing
15.   Discharge auger
16.  Grain elevator
17.  Engine
18.   Conveyor tightner
19.  Suspending strap for housing

Threshing started as soon as the first shocks were put up in the
fall, until mid-winter. Days would start early with Mr. Yockers
leaving his farm before sunrise with members of his crew, pulling
the machine with his truck to the designated field. At the field,
the machine would be set up and serviced, then the threshing would
begin. The machine would be pulled from shock to shock by the
truck, the grain elevated into a wagon or truck supplied by the
farmer. The crew of about five, sometimes helped by the farmer or
his workers, would form a line, each grab a bundle, and feed the
machine, then carry the bundle back and start building a shock of
the threshed bundles. So a circle would form, constantly moving,
tearing down a shock and building another. When one shock was
finished, the machine would be moved and another shock thrashed,
continuing in this fashion until the whole field was done. Mr.
Yockers, being thresherman, just watched over the machine and moved
it from shock to shock, but mostly just stood and watched. This
being Kansas, with its freaky winter weather, some days would be
warm to bitter cold. On cold days, the line moved a little faster
than usual and the crew kept reasonably warm, while Mr. Yockers
would have to stamp his feet and wave his arms to keep warm. Of
course, depending upon the neighborhood, there was usually warmth
in liquid form in a jug, supplied by the farmer and kept hidden in
a shock. But on the warm days, feeding the machine could be rather
miserable, not only the heat, but the dust the machine produced
irritated the men. One old farmer who used to help Mr. Yockers told
me that work went all through the day, stopping shortly at noon. In
mid-afternoon, on warm miserable days, one of the crew would
‘accidently’ let one of the bundles slip and go on through
the machine. It usually took about a half an hour to unclog the
machine, providing a much-needed rest and an excellent opportunity
to cuss the machine, the work, and everything in general.

Mr. Yockers continued this sorghum threshing until the early
1950’s, keeping always with his two original machines. About
the time he quit, he pulled the second machine he made, into his
farm, and tore it apart. Nobody seems to know why he did it, the
machine was in good shape, it just seems to be a spur of the moment
thing he did. He kept the original machine until his farm sale a
couple of years ago when I bought it. So it looks tike I have the
only animal like it in captivity. Mr. Yockers and his wife are
still living and well. I visited them a month or so ago when I was
compiling this article. Mr. Yockers, a little past eighty years, is
as spry as ever and Mrs. Yockers as talkative as ever. They were
glad to know where the machine had gone to and that it was being
cared for. They also gave me quite a bit of information about the


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