IMPROVEMENTS IN MACHINERY FOR GRINDING CORN
Year: 1874

page_text: LETTERS PATENT to Herbert Ibbotson, of Hollins Mill, near Sheffield,
in the County of York, for the Invention of "IMPROVEMENTS IN
MACHINERY FOR GRINDING CORN."
Sealed the 16th June 1874, and dated the 10th March 1874.
:
PROVISIONAL SPECIFICATION left by the said Herbert Ibbotson at
the Office of the Commissioners of Patents, with his Petition, on
the 10th March 1874.
I, HERBERT IBBOTSON, of Hollins Mill, near Sheffield, in the County
of York, do hereby declare the nature of my said Invention for
"IMPROVEMENTS IN MACHINERY FOR GRINDING CORN," to be as follows:-
This Invention relates to improvements in adjusting and regulating
the top stone of mills used for grinding corn, more especially in the
grinding of wheat into flour, whereby a superior quality as well as an
O increase in the yield is obtained.
In coming out my Invention as annlied to the ordinary arrangement

page_text: supported by and revolving in a bearing called the "footstep," this
footstep is carried by a lever; one end being a strong joint, is secured to
a beam known as the "bridge tree;" the other end of the lever is sup-
ported by an adjusting screw, whereby the lever shaft and stone are
raised or lowered as may be necessary. Now between the end of the
lever and the adjusting screw I place a spring of any suitable material,
by preference of spiral shape (if of steel), but of such a strength that
it will bear up the weight of the stone and shaft and lever when
partially closed. The effect of this spring is a certain amount of self-
adjustment in the distance between the top and bottom stones, and also
a peculiar giving or yielding motion to the top stone, so that the flour is
not crushed to the extent that becomes damaging to its quality or
colour.
'
Although in the above ordinary arrangement of the stones of a flour-
grinding mill I prefer to place the spring between the end of the lever
that carries the upright shaft and the top stone and the adjusting screw,
as being the most suitable position for it, I do not bind myself to the
exact position of the spring, as it may obviously be placed directly under
the footstep or at the end of the lever, the position varying with the
construction of the mill.
If desirable I use in place of a spring a lever with adjustable balance
weight.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Herbert Ibbotson in the Great Seal Patent Office
...on the 19th August 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HERBERT
IBBOTSON, of Hollins Mill, near Sheffield, in the County of York, send
greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of March, in the year of our Lord
One thousand cight hundred and seventy-four, in the thirty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and
:

page_text: i
grant unto me, the said Herbert Ibbotson, Her special license that I, the
said Herbert Ibbotson, my executors, administrators, and assigns, or such
others as I, the said Herbert Ibbotson, my executors, administrators, or
assigns, should at any time agree with and no others, from time to
time and at all times thereafter during the term therein expressed
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN MACHINERY FOR
GRINDING CORN," upon the condition (amongst others) that I, the said
Herbert Ibbotson, my executors or administrators,. by an instrument in
writing under my hand and seal, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I; the said Herbert Ibbotson, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings,
and to the letters and figures, marked thereon, that is to say :-
This Invention relates to improvements in adjusting and regulating
the top stone of mills used for grinding corn, more especially in the
grinding of wheat into flour, whereby a superior quality as well as an
increase in the yield is obtained.
་
It consists in placing between the end of the lever carrying the
footstep and shaft of the top stone and the adjusting screw. of the said
lever a spring of such a strength that it will keep up the weight of the
stone shaft and lever when partially closed, the effect being a certain
amount of self-adjustment in the distance. between the top and bottom
stones, and also a peculiar giving or yielding motion of the top stone,
whereby the flour is not crushed to the extent that becomes damaging
to the quality or color.
Or in lieu of applying the said spring as described it may be placed
directly under the footstep or at the other end of the lever, or in any
other convenient position, according to the construction of the mill.
:
If desirable a lever with adjustable balance weight may be substituted

page_text: "And in order that my said Invention may be fully understood I
shall now proceed more particularly to describe the same, and for that
purpose shall refer to the several Figures on the annexed Sheet of
Drawings, the same letters of reference indicating corresponding parts in
all the Figures.
Figure 1 is a side elevation of that part of a mill for grinding corn to
Invention is applied.
which my
A represents the lower portion of the upright shaft carrying the top
stone. To this lower portion is secured the bevel wheel B driven by a
similar driving wheel B' on the horizontal shaft C as shewn.
The lower end of the upright shaft A is stepped, and revolves in a
bearing D called the footstep, which rests upon or is carried by the
lever E, having its fulcrum at or jointed at one end by a pin F to the
under side of the beam G, technically termed the "bridge tree." The
outer or opposite end of the lever E (between which end and the fulcrum
the footstep D is carried) is supported or held up by a screw or rod H,
which is capable of being raised or lowered, or is adjustable as required
by means of the bell crank I worked by the wheel and scrow K as
shewn.
1
Ordinarily the said outer end of the lever E takes its bearing or rests
directly on the nut x at the lower end of the screw or rod H, but in this
case I clongate the latter and place between the nut x and the outer end
of the lever E a spring L of steel or other suitable material, on which
the said lever bears or rests. The elasticity thus produced has the effect
of ensuring a certain amount of self-adjustment in the distance between
the top and bottom stones, and also of giving a peculiar yielding motion
to the top stone, whereby the flour is not crushed to the extent that
becomes damaging to its quality or color.
Although in the above ordinary arrangement of the stones of a flour-
grinding mill I prefer to place the spring L between the end of the
lever E and the nut x of the screw or rod H, as being the most suitable
position for it, I do not bind myself to the exact position of the spring,
as it may obviously be placed directly under the footstep D or at the
other end of the lever E, the position varying with the construction of
the mill.
In Figure 2 the spring L¹, which in this case is shewn as a volute, is

page_text: placed in the centre of the lever E', and supports the footstep D', which
is placed on the top of the said spring.
-
In Figure 3 the spring L is applied to the fulcrum or joint end of
the lever E, in which caso there might be a spring at one or both
ends.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is, the application
and use of a spring to the lever carrying the footstep, the upright shaft,
and the top stone of a mill for grinding corn, substantially as and
for the purposes herein-before described and illustrated by my Drawings.
In witness whereof, I, the said Herbert Ibbotson, have to this my
Specification set my hand and scal, the Seventeenth day of
August One thousand eight hundred and seventy-four.
HERBERT IBBOTSON. (L.S.)