IMPROVEMENTS IN THE BOSSES APPLIED TO MILLSTONES
Year: 1854

page_text: LETTERS PATENT to John Harrison, of Brighouse, in the County of
York, Millwright and Engineer, for the Invention of "IMPROVEMENTS IN
THE BOSSES APPLIED TO MILLSTONES."
Sealed the 13th April 1855, and dated the 14th October 1854.
PROVISIONAL SPECIFICATION left by the said John Harrison at the
Office of the Commissioners of Patents, with his Petition, on the
14th October 1854.
I, JOHN HARRISON, of Brighouse, in the County of York, Millwright and
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE BOSSES APPLIED TO MILLSTONES" to be as follows:-
My said Invention consists in applying springs to the bosses used for driving
or propelling millstones, which are at present used without any springs
whatever.
The driving parts of millstones being so constructed that the stones cannot
give way or yield in the smallest degree to any sudden shock or irregularity,
often occasions the twisting or breaking of the spindle end, the millstones
travelling at a great velocity, but which I obviate by introducing spiral or other
springs. To effect this, the boss is bored at cach lug to admit a hoop or series
of hoops, and is open at one end to receive a spiral or any other suitable spring
of sufficient strength, and the boss is closed at the end adjoining the driving

page_text: bar, so as to preserve the spring end from damage, and the spring being made
to fit tight without play in the hoop. The hoops are turned to fit exactly
within the opening bored to receive them, allowance being made for them to
press in or out, as required. The hoops are made shorter than the springs,
so that the hoops are allowed to work inwards when the weight is applied;
but the spring end requires to have abutment; consequently the hoop works
over that part of the spring which is uncovered when the hoop is pressed
inwards. I also use set screws to force the back spring or following springs
up to the centre or driving bar, that the springs may act equally on all sides
thereof.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Harrison in the Great Seal Patent Office on the
13th April 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HARRISON, of Brighouse, in the County of York, Millwright and Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of October, in the year of our
Lord One thousand eight hundred and fifty-four, in the seventeenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant. unto
me, the said John Harrison, Her special licence that I, the said John
Harrison, my executors, administrators, and assigns, or such others as I, the
said John Harrison, my executors, administrators, and 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
THE BOSSES APPLIED TO MILLSTONES," upon the condition (amongst others) that
I, the said John Harrison, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said Inven-
tion, 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 John Harrison, 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 state-
ment:
-

page_text: My said Invention consists in a peculiar application of springs to the bosses
used for driving or propelling millstones, which are at present used without
any springs whatever.
And for the better understanding of my said improvements, I will now
proceed to describe the same in detail, reference being had to the Drawings
hereunto annexed, in which the same letters refer to like parts throughout.
DESCRIPTION OF THE DRAWINGS.
Figure is a plan, and Figure 2-is a side elevation, of my improved self-
adjusting and spring boss.
A, A, is the centre or balanced bar, fastened in the eye of the millstone;
B, B, the boss; C, C, C, C, iron hoops, open at one end to receive the spiral
springs, and closed at the other end to preserve the spring end from being
damaged by the centre bar or any other cause. The holes C' in the boss,
Figure 2, are accurately bored to receive the hoops, allowing them to work
firmly in or out, as the case may be; the hoops are bored to receive the springs
D, D, D, D, and are shorter than the springs as shown in D and C, Figure 1,
in order to allow them to work inwards. When the pressure is applied, the
ends of the holes a, a, form butments for the springs; and the other ends of
the springs are acted upon by the inside of the hoops at b, which are pressed
inwards by the centre bar A, covering the springs as they slide inwards. E, a
set screw, to set the spring and hoop up to the centre bar, thereby securing
the centre bar between the springs, causing the millstones to spring backwards
or forwards, according to the vibration; and c is the centre on which the
bar A rests.
It will thus be seen that instead of the driving parts of the millstones when
constructed according to my said Invention being erected so that the stones
cannot give way or yield in the smallest degree to any sudden shock or
irregularity, that I obviate this defect by introducing a self-adjusting arrange-
ment of spiral steel springs or other suitable springs. To effect this, the boss
is bored at each lug to admit a hoop or series of hoops, and is open at one
end to receive a spring or springs of sufficient strength; and the boss is closed
at the end adjoining the driving bar, so as to preserve the spring end from
damage, the spring being made to fit tight without play in the hoop. The
hoops are turned to fit exactly within the opening bored to receive them,
allowance being made for them to press in or out, as required. The hoops
are made shorter than the springs, so that the hoops are allowed to work
inwards when the weight is applied; but the spring end requires to have abut-
ment; consequently the hoop works over that part of the spring which is

page_text: uncovered when the hoop is pressed inwards. I also use set screws to force
the back spring or following springs up to the centre or driving bar, that
the springs may act equally on all sides thereof.
Having thus fully described my said improvements for removing that
rigidity which at present exists in the driving parts of millstones, and which
often occasions the twisting or breaking of the spindle end and other parts
when the millstones are travelling at a great velocity, I would here observe
that I do not limit myself to any particular dimensions or materials or forms
of the several parts described, or the precise method in which the same is
applied, so long as the mechanical result is the same; and I do declare that
what I claim as my Invention is, namely,―
The novel construction and application of bosses for driving millstones,
provided with springs of suitable forms and materials, as described.
In witness whereof, I, the said John Harrison, have hereunto set my
hand and seal, this Seventh day of April, in the year of our Lord
1855.
JOHN HARRISON. (..)