IMPROVEMENTS IN MACHINERY FOR DRESSING AND CLEANING RICE AND OTHER GRAIN
Year: 1871

page_text: LETTERS PATENT to Frederick Woodbridge, of No. 81, Great Tower
Street, in the City of London, Rice Cleaner, for the Invention of
" IMPROVEMENTS IN MACHINERY FOR DRESSING AND CLEANING RICE AND
OTHER GRAIN."
Sealed the 16th January 1872, and dated the 23rd November 1871.
PROVISIONAL SPECIFICATION left by the said Frederick Woodbridge
at the Office of the Commissioners of Patents, with his Petition,
on the 23rd November 1871.
I, FREDERICK WOODBRIDGE, of No. 81, Great Tower Street, in the
City of London, Rice Cleaner, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MACHINERY FOR DRESSING AND CLEANING
RICE AND OTHER GRAIN," to be as follows
In machinery now used for dressing and cleaning rice the rice is
subjected to the action of a rapidly revolving stone, which is mounted
concentrically within a cylinder formed at its circumference of wire
gauze. This cylinder is mounted horizontally, and is also caused to

page_text: revolve slowly. The axes of the cylinder are hollow and are closed in
at their ends by fixed plates, the hollow axes being supported in circular
recesses in these plates. The rice to be cleaned is fed into the cylinder
from hoppers through openings in these plates, and as the husk and
skin are ground off from the grains by the action upon them of the
rapidly revolving stone they are carried away by the current of air
thrown off from the stone and escape through the wire gauze. When,
however, the stone becomes worn away by the friction of the rice against
its circumference and the diameter of the stone has thus been consi-
derably reduced, the impurities removed from the rice are not expelled
sufficiently quickly from the drum, and the action of the machine is
impaired, as the proper cleaning of rice depends greatly upon the
impurities being quickly carried away so soon as they are detached
from the grain. To remedy this, in place of receiving the hollow axes
which are at the ends of the cylinder in circular recesses in the fixed
end plates, so that the cylinder always remains concentric with the axis
of the stone as heretofore, I receive the hollow axes of the cylinder in
bearings, which can be slid to and fro in guides on the fixed end plates,
so that as the stone becomes worn away and the distance between the
cylinder and the stone becomes increased, the cylinder can be raised so
as to bring the lower portion of its circumference nearer to the stone,
and thus the proper working distance between the lower part of the
stone and the drum can always be maintained, and yet allow both the
stone and the cylinder always to revolve freely in their bearings.
Various ways may be adopted for moving to and fro the slides in
which the bearings for the axes of the cylinder are formed; I, however,
prefer that they should each rest on a lever capable of turning at one
end on a pin joint, and of being raised or lowered at the other end by
a screw or otherwise. The upper part of the bearings in which the
hollow axes are received is also made capable of being removed; this
allows of one-half of the gauze cylinder (which is made in two parts as
usual) being quickly taken away whenever it is desired to re-dress the
surface of the stone.
When a revolving brush is employed within the cylinder in place of
a stone, the cylinder may be mounted in a similar manner to that above
decorihed

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Woodbridge in the Great Seal Patent
Office on the 23rd May 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
WOODBRIDGE, of No. 81, Great Tower Street, in the City of London,
Rice Cleaner, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of November, in
the year of our Lord One thousand eight hundred and seventy-one, in
the thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Frederick Woodbridge, Her
special license that I, the said Frederick Woodbridge, my executors,
administrators, and assigns, or such others as I, the said Frederick
Woodbridge, 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 MACHINERY FOR DRESSING AND CLEANING RICE AND OTHER
GRAIN," upon the condition (amongst others) that I, the said Frederick
Woodbridge, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, 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 Frederick Woodbridge, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
In machinery now used for dressing and cleaning rice the rice is
subjected to the action of a rapidly revolving stone, which is mounted
concentrically within a cylinder formed at its circumference of wire
gauze. This cylinder is mounted horizontally, and is also caused to
revolve slowly. The axes of the cylinder are hollow, and are closed in
at their ends by fixed plates, the hollow axes being supported in circular.

page_text: recesses in these plates. The rice to be cleaned is fed into the cylinder
from hoppers through openings in these plates, and as the husk and skin
are ground off from the grains by the action upon them of the rapidly
revolving stone, they are carried away by the current of air thrown off
from the stone and escape through the wire gauze. When, however,
the stone becomes worn away by the friction of the rice against the
circumference, and the diameter of the stone has thus been considerably
reduced, the impurities removed from the rice are not expelled suffi-
ciently quickly from the drum, and the action of the machine is impaired,
as the proper cleaning of rice depends greatly upon the impurities being
quickly carried away so soon as they are detached from the grain. To
remedy this, in place of receiving the hollow axes which are at the ends
of the cylinder in circular recesses, in the fixed end plates, so that the
cylinder always remains concentric with the axes of the stone as here-
tofore, I receive the hollow axes of the cylinder in bearings, which
can be slid to and fro in guides on the fixed' end plates, so that as the
stone becomes worn away and the distance between the cylinder and
the stone becomes increased, the cylinder can be raised so as to bring
the lower portion of its circumference nearer to the stone, and thus the
proper working distance between the lower part of the stone and the
drum can always be maintained, and yet allow both the stone and the
cylinder always to revolve freely in their bearings.
.
Various ways may be adopted for moving to and fro the slides in
which the bearings for the axes of the cylinder are formed; I, however,
prefer that they should each rest on a lever capable of turning at one
end on a pin joint, and of being raised or lowered at the other end by
a screw or otherwise. The upper part of the bearings in which the
hollow axes are received is also made capable of being removed; this
allows of one-half of the gauze cylinder (which is made in two parts
as usual) being quickly taken away whenever it is desired to re-dress
the surface of the stone.
In order that my said Invention may be most fully understood and

page_text: longitudinal section; and Figures 5 and 6 are transverse sections of
the same.
a, a, is the frame of the machine. It has upon it the bearings b, b,
in which the axis c is carried and caused to rotate rapidly. d is a
grindstone, mounted on the axis c.
e, e, are guides upon the frame a
to carry the sliding bearings f, f, which receive the hollow axes or
trunnions g, g, of the cylindrical case h, h. The case h is made in two
parts, which are firmly fixed together when the machine is at work,
and the periphery of the case is formed of wire gauze supported on
cross bars. In the ends of the case there are also apertures h* closed
with wire gauze. They serve to admit air into the casing as the rapid
rotation of the stone throws off the air and causes it to escape at the
periphery. h¹, h³, are holes in the ends of the cylinder by which the
grain to be operated upon is introduced through hoppers or shoots, and
which also serve to admit air to the case. h is a door, which is opened
to discharge the grain when the husk has been rubbed off. There is a
ring of teeth h³ around the cylinder gearing with a pinion i, by means
of which the cylinder is slowly rotated. The teeth h³ and pinion i are
only shewn in Figure 2. The sliding bearings f,f rest upon levers k, k,
which can turn upon the pin joints ¹ at one end, and at the other are
jointed to the stems 1, 1. These stems can be raised or lowered by the
hand nuts n, n, and in this way the case can be set so as to maintain
constantly the best working distance between its periphery and the
surface of the stone, notwithstanding the progressive wearing away of
the stone by its friction on the grain.
In Figure 6 the casing is shewn in a position eccentric to the stone
as it usually is when the machine is at work, especially when the stone
has become more or less worn, and I find that in this position the
machine works better, and there is less breakage of the grain than when
the stone is in the centre of the case, where heretofore it has always been
the practice to place it. As the stone decreases in diameter it is caused
to make a proportionally greater number of revolutions by shifting its
driving belt from one driving pulley to another.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that I do
not confine myself to the exact details described as the mechanism for
adjusting the parts so that the case and the stone may be eccentric the
one to the other may be varied, but what I claim as my improvements

page_text: under surface of the grindstone a to the periphery of the case 7 may
be adjusted to compensate for the wear of the stone, substantially
as described.
In witness whereof, I, the said Frederick Woodbridge, have here-
unto set my hand and seal, this Twenty-second day of May, in
the year of our Lord One thousand eight hundred and seventy-
two