IMPROVEMENTS IN APPARATUS FOR VENTILATING MILLSTONES, AND IN MACHINERY FOR SEPARATING THE
Year: 1873

page_text: LETTERS PATENT to Henry Smith, of Birmingham, in the County of
Warwick, Miller, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR VENTILATING MILLSTONES, AND IN MACHINERY FOR SEPARATING THE

page_text: In the ordinary method of ventilating millstones the stones are
enclosed in a case which only permits air to enter by the central opening
in the top stone, called the eye. The air thus entering passes between
the stones from the centre to the circumference, from whence it ascends
into trunks or flues through the stove room to the atmosphere. By this
arrangement the air which on passing between the stone takes with it
a quantity of moisture from the meal becomes cooled as it ascends in
the casing, and deposits moisture on the inside of the casing, to which
moisture some of the meal attaches itself. There is thus formed a paste
which becomes putrid, and which not only injures the meal passing
over it, but falls off the casing from time to time and mixes with the
meal.
By my improvements in ventilating millstones herein-after described,
the casing is not closed at top, and the current of air passes mainly
outside the stones, and pursues the same descending motion as the
meal until it diverges into a trunk or flue below the level of the mill-
stones.
By my improvements the cooling and drying of the meal is effected
without the inconveniences herein-before described which attend the
ordinary method of ventilating millstones.
The improvements constituting my Invention are constructed and
arranged in the following manner:-I fix a horizontal trunk or flue at
a level somewhat lower than the bottom of the millstones, the meal
spout down which the meal passes from the stones communicating at
about its middle with the said horizontal trunk or flue. The stones are
enclosed in a casing which terminates at a distance from the eye of the
top stone, so that there is free access of air at the top of the stones.
The horizontal flue communicates with a vertical trunk or flue passing
out at the top of the building and opening into the atmosphere. In the
said vertical flue is a separator. This separator consists of a case,
through the bottom of which the vertical flue passes. The said' vertical
flue opens into an inverted cone or conical sieve of wire gauze or
perforated metal situated within the case. In the axis of the conical
sieve is a rotating shaft driven by a band and pulley or other gearing.
This shaft carries a series of radial vanes and brushes alternating with
one another. On the rotation of the shaft carrying the said vanes, and
brushes the particles. of meal are driven by centrifugal force against the

page_text: wire gauze or perforated metal of the sieve by the action of the vanes,
part passing through and part lodging thercon, and by the action of the
brushes the meal lodging on the said wire gauze or perforated metal is
brushed through the said gauze or metal, and collects on the floor of the
case of the separator.
The air deprived of its meal or dust passes from the top of the
separator into a small chamber, and from thence into the atmosphere.
By the rotation of the top stones the action of the vanes of the
separator and the ascending force of the heated column of air in the
vertical trunk or flue, two currents are produced, one from the stones
passing down the upper part of the meal spout into the horizontal trunk
or flue, and another up the lower part of the meal spout into the said
trunk or flue. These currents pass through the separator into the
atmosphere. By means of these currents the stones and meal are kept
cool, and the air is effectually deprived of the meal or dust brought with
it as it passes to the separator. Any number of stones may be connected
to the horizontal trunk or flue described. The quantity of air entering
the meal spouts from above and below is regulated by dampers and by a
valve on the top of the separator.
Although I prefer to fix the horizontal trunk or flue at a level below
the millstones, yet I do not confine myself to that position, as. the
said trunk or flue may be placed at a higher level with the same effect,
provided the air from the millstones be made to take the downward
course described into the meal spout, before entering the said horizontal
flue.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Smith in the Great Seal Patent Office on
the 27th September 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
SMITH, of Birmingham, in the County of Warwick, Miller, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of April, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-

page_text: sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Henry Smith, Her special license that
I, the said Henry Smith, my executors, administrators, and assigns, or
· such others as I, the said Henry Smith, 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 APPARATUS FOR
VENTILATING MILLSTONES, AND IN MACHINERY FOR SEPARATING THE FINE MEAL ]
FROM THE CURRENTS OF AIR PASSING FROM MILLSTONES," upon the condition
(amongst others) that I, the said Henry Smith, my executors or adminis-
trators, 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 Henry Smith, 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:
.
My Invention has for its object to ventilate and keep cool millstones
and the meal ground thereby more effectually than can be done by the
means in common use, as well as more effectually to separate the fine
meal from the current of air employed to ventilate the millstones.
:
In the ordinary method of ventilating millstones the stones are
enclosed in a case which only permits air to enter by the central opening
in the top stone called the eye. The air thus entering passes between
the stones from the centre to the circumference, from whence it ascends
into trunks or flues through the stive room to the atmosphere. By this
arrangement the air, which on passing between the stones takes with it
a quantity of moisture from the meal, becomes cooled as it ascends in
the casing and deposits moisture on the inside of the casing, to which
moisture some of the meal attaches itself. There is thus formed a paste,
which becomes putrid, and which not only injures the meal passing
over it, but falls off the casing from time to time and mixes with the
mcal.

page_text: By my improvements in ventilating millstones herein-after described
the casing is not closed at top, and the current of air passes mainly
outside the stones and pursues the same descending motion as the meal,
until it diverges into a trunk or flue below the level of the millstones.
By my improvements the cooling and drying of the meal is effected
without the inconveniences hercin-before described which attend the
ordinary method of ventilating millstones.
The improvements constituting my Invention are constructed and
arranged in the following manner:-I fix a horizontal trunk or flue at a
level somewhat lower than the bottom of the millstones, the meal spout
down which the meal passes from the stones communicating at about its
middle with the said horizontal trunk or flue. The stones are enclosed
in a casing which terminates at a distance from the eye of the top stone,
so that there is free access of air at the top of the stones. The horizontal
flue communicates with a vertical trunk or flue passing out at the top of
the building and opening into the atmosphere. In the said vertical flue
is a separator. This separator consists of a case, through the bottom of
which the vertical flue passes. The said vertical flue opens into an
inverted cone or conical sieve of wire gauze or perforated metal situated
within the case. In the axis of the conical sieve is a rotating shaft
driven by a band and pulley or other gearing. This shaft carries a scries
of radial vanes and brushes alternating with one another. On the
rotation of the shaft carrying the said vanes and brushes the particles of
meal are driven by centrifugal force against the wire gauze or perforated
metal of the sieve by the action of the vanes, part passing through and
part lodging thereon, and by the action of the brushes the meal lodging
on the said wire gauze or perforated metal is brushed through the said
gauze or metal and collects on the floor of the case of the separator.
The air deprived of its meal or dust passes from the top of the
separator into the atmosphere.
Having explained the nature of my Invention I will proceed to
describe with reference to the accompanying Drawings the manner in
which the same is to be performed.
Figure 1 represents partly in elevation and partly in section my
improved ventilating apparatus and separating machinery applied to
four pairs of millstones, and Figures 2, 3, 4, 5, 6, and 7, represent the

page_text: separator detached drawn to a larger scale. The same letters indicato
the same parts in the several Figures of the Drawings; a are the top
running stones, and 6 are the bottom fixed stones; c is the casing of the
millstones, the said casing terminating at a short distance from the eye
of the top stone a so as to leave an opening & for the free access of air
to the top of the stones; d is the horizontal trunk or flue below the
millstones a, b, the said flue or trunk d communicating with the vertical
trunk or flue e; f, f, are the meal spouts in connection with the
casings c of the stones. The air entering the casings c at the openings
d², after circulating mainly about the outsides of the stones a, b, passes
to the meal spouts as indicated by the arrows. Each of the said meal
spouts is forked immediately below the horizontal trunk or flue d. The
said meal spouts, besides conveying the meal from the casings of the
millstones, also communicate by means of the branch pipes f³ with the
horizontal trunk or flue d. By this arrangement of parts the exhaustion
produced by the separator hereinafter described or other exhausting.
apparatus causes a downward current of air from the stones to enter the
flued from the upper part f of the meal spout as indicated by the
arrows. The upper part of the meal spout is provided with a damper h,
and the branch pipe f³ with a damper i. By means of the damper /
the quantity of air passing from the casing of the stones is regulated,
and by means of the damper i the whole quantity of air passing from
the meal spout into the flue or trunk.d is regulated. The volume of air
passing through the trunks d and e is also regulated by the valve of the
separator herein-after described. At the top of the vertical trunk or
flue e is the separator, by means of which the particles of fine meal are
separated from the ascending current of air as well as an exhaustion of
air produced.
.
This separator is represented in connection with the mill in Figure 1,
and separately on a larger scale in side elevation in Figure 2, vertical-
section in Figure 3; plan in Figure 4, and horizontal section in Figure 5;
Figure 6, represents a plan of the under side of the sieve, and Figure 7
a plan of a portion of the valve of the separator. The said separator
consists of a case k fixed on the upper floor of the mill, through the
bottom of which case the vertical trunk or flue e passes. Within the
said case k an inverted cone or conical sieve 7 of perforated metal (or wire
gauze or coarse cloth) is fixed. In the axis of the said conical sieve
is a rotating shaft. m driven by a band passing over the pulley n on its

page_text: jo
top (see Figure 1). The said shaft m carries a series of vanes p, p, best
seen in Figure 5. The bottom of the sieve opens into the top of the
vertical flue or trunk e and the current of air passing through the said
trunk e ascends through the said sieve. The top of the sieve 7 is opened
more or less so as to regulate the quantity of air passing through the
said sieve by means of the valve q. This valve is raised and lowered by
the lever and cord or chains, the said valve sliding upon the guides t
on the inner side of the case k; ut is a cross bar through which the shaft
m carrying the vanes p works; v (see Figure 1) is a spout in commu-
nication with the space situated between the sieve and interior of the
case / down which spout the meal which collects in the said case k
passes. By the rotation of the vanes p, p, the particles of fine meal
ascending with the current of air in the sieve are driven by centrifugal
action through the perforations of the said sieve into the case k, on the
floor of which the meal collects and passes by the spout to a receiver.
The rotation of the vanes p, p, at the same time produces an exhaustion
of air within the separator, by means of which in conjunction with the
apparatus represented in Figure 1, the ventilation of the millstones is
effected. The air mainly deprived of its fine meal or dust passes from
the top of the separator through the valve q into the room in which the
separator is situated, or it may be conveyed direct into the atmosphere
or treated in the apparatus herein-after described. Instead of using the
vanes p, p, alone brushes may alternate with the said vanes. In this
case any meal which may lodge in the perforated parts of sieve is
brushed through the perforations by the said brushes into the case k. I
prefer to make the large perforations in the upper part of the sieve
by partly piercing the metal of the said sieve and bending outwards the
parts so pierced so as to form a series of small tongues on the exterior
of the sieve, as illustrated in Figure 6, but I do not limit myself to this
method of forming the perforations. The case % of the separator is
provided with a door ³ (see Figure 2) for gaining access to the exterior
of the sieve. By the rotation of the top stones a the action of the
vanes p, p, of the separator and the ascending force of the column of
warm air in the vertical trunk or flue e, the stones and meal are kept
cool and the air is effectually deprived of the meal or dust brought
with it as it passes through the separator. Any number of stones may
be connected to the horizontal trunk or flue d.
Although I prefer to fix the horizontal trunk or flue d at a level below
the millstones, yet I do not confine myself to that position, as the said

page_text: provided the air from the millstones be made to take the downward
course described and represented into the meal spout before entering the
said horizontal trunk or flue, and although I prefer to use the separator
described in conjunction with my improved ventilating apparatus yet a
fan or other exhausting machine may be used with the said ventilating
apparatus in place of the said separator...
The ascending current of air after it leaves the separator herein-before
described may be made to pass through the apparatus represented in
Figure 8, for the purpose of further depriving it of the meal contained
in it. The said apparatus consists of an upper cistern 2, containing
water, and a lower cistern 3, the pipe 4 conveying the ascending current
of air opening into the pipe 5 of the lower cistern 3. In the said pipe 5 is
a rose 6, which is fixed on the end of a pipe passing from the lower part
of the top cistern 2. By means of the said rose 6 a shower of water
drops meets the ascending current of air, and deprives it of the fine
particles of meal it contains, which meal is carried into the water in the
cistern 3. The water falling into the cistern 3 is supplied to the cistern 2
by the endless band carrying buckets 8, which on the motion of the
said endless band dip into and take water from the lower cistern 3, and
after ascending to the top of the apparatus empty themselves into the
cistern 2.
My improved construction of separator may be applied to other
apparatus used for ventilating millstones, besides that with which it is
represented in conjunction.
.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do
not limit myself to the precise, details herein described, and illustrated,
as the same may be varied without departing from the nature of my
Invention; but I claim as my Invention,-
1.
First., The construction and arrangement of the parts of apparatus for
ventilating millstones, herein-before described and illustrated in, the
accompanying Drawings, that is to say, constructing and arranging the
casing of the millstones so that a current of air produced by an exhaust-
ing apparatus shall enter the casing near the middle of the top stone,
and after circulating between the exterior of the stones and the said
casing enter the meal spout, from which it passes into a horizontal

page_text: trunk or flue situated by preference at a level below that of the millstones,
substantially as described and illustrated.
Secondly. The construction and combination of the parts of tho
separating machinery herein-before described and illustrated in the
accompanying Drawings, for separating the fine meal from the current
of air from the millstones, that is to say, constructing and combining
the parts of the said separating machinery so as to produce an exhaust
current of air from the millstones, which exhaust current of air is made
to pass through the separator, and is thereby deprived of the fine meal
contained in it, substantially as described and illustrated, whether the
said separating machinery be used in conjunction with millstones
ventilated in the manner described, or with millstones ventilated in any
other manner.
In witness whereof, I, the said Henry Smith, have hereunto set
my hand and seal, this Twenty-third day of September, in the year
of our Lord One thousand cight hundred and seventy-three.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
Birmingham.
HENRY SMITH. (L.S.)