Year: 1888

page_text: Date of Application (in United Kingdom), 10th Sept., 1888
Complete Specification Left, 10th Sept., 1888
Complete Specification Accepted. 6th Apr., 1889
I NOAH WILLIAM HOLT. of Manchester, State of Michigan, United States of
America, Engineer, do hereby declare the nature of this invention, and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
Fig. is a central vertical section of a machine containing my invention taken on
line
Fig. 2. Fig. 2 is a top plan view. Fig. 3 is a horizontal section on line y y
Fig. 1. Fig. 4 is a horizontal section on line = = Fig. 1. Figs. 5, 6 and 7 are
details. Fig. 8 is a vertical section showing the machine adapted for use as a dust
collector only. Fig. 9 shows a modification.
This invention relates to a separating machine in which the material fed in is
divided into different grades according to its specific gravity, both the lighter and
heavier particles being delivered through their respective outlets, the lighter particles.
being collected in and discharged from a chamber which is separate and apart from
the aspirating chamber.
In the machine shown in the drawings, A A.represents generally the frame-work
of the machine.
B B is an inclosing shell or casing, of which the lower part B is funnel-shaped, the
upper part B being preferably circular in cross section and of uniform diameter
throughout. is a shell or casing preferably circular in cross section and of uniform
diameter, but of less diameter than the shell B₁ and arranged. concentric therewith;

page_text: these parts forming between them an annular chamber closed at its upper side by
a deck or top plate. is a flange projecting inward from the shell C a short distance
above its lower edge, and is by preference, made of wood and secured by screws
passing through the shell and into the periphery of this flange.
D) is a ring or downward projecting flange, connected at its upper edge to the inner
edge of the flange c, and preferably funnel-shaped as indicated.
E is a funnel-shaped shell concentric to the outer shell B and somewhat larger at its
upper end than is the flange D at its lower edge which projects down a short distance
within the shell E. I propose to connect the upper end of this shell E with either the
shell B or the shell D, or both, by means of ties or braces e e, see Fig. 1.
FF are the blades of the fan, the vertical shaft G of which is supported at its
upper end in a bearing which in turn is supported in the upper wall H of the
fan case, and at its lower end in a bearing or step h, which is connected to and
carried by other parts of the machine as will be explained.
I is the bottom wall or head of the fan which is connected to and supported upon
the flange c by means of arms or brackets i i.
The shell of the fan case is by preference not circular but somewhat scroll-shaped
as indicated in Fig. 4, the mouth of the fan opening into the annular space or dust
separating chamber between the concentric shells B₁°C.
The section of this wall of this annular space may be made in a separate piece,
or it may consist of one end of the parts bent backwards so as to form one side
of the mouth of the fan.
JJJ represent the outer shell or inclosing casing of an aspirator chamber, the
open upper end of which connects with the eye of the fan, and in fact, by preference
is fitted tightly into this eye and is secured thereto by screws or pins, when that head
of the fan case is made of wood; or it may be soldered thereto when that head
is made of sheet metal.
By preference, the central or intermediate section J of this aspirator shell is not
only circular but cylindrical; and j j are a series of rings of different diameters
arranged concentrically within the part J.
j¹ ja
are a series of funnel-shaped rings arranged one within another, and each
connected at its upper edge to the lower edge of one of the cylinder shaped rings j.
Thus there is foruied within the shell of the aspirator, a series of annular chambers,
see particularly Figs. 1, 6 and 7.
KK are a series of flaring rings, three in number and of different diameters; the
upper smallest one being suspended by its upper edge from the lower edge of the
inner funnel-shaped ring j as for example by ties. The next larger ring K is
suspended in like manner from the ring K above it and so on.
LL are respectively the arms and hollow sleeves of a spider, the spokes or arms L
of which are inclined downward and outward from the sleeve L' and are, at their
lower ends, attached to horizontal plates or bars by rivetting or soldering. Or these
arms L may be bent outward on horizontal lines to take the place of the plates 1.
jj represent a series of valves rings or dampers attached by their upper edges to
the plates or bars and fitting closely the outer faces of the rings jj and projecting
downward below their lower edges (when in the position shown in Fig. 1) and into
the annular spaces or channels or throats between the funnel-shaped rings jj and
between the outermost of these rings and the part J of the aspirator shell.
L² is a lever projecting through the fan head and the shell J and connected at its
inner end to the sleeve L whereby the valves may be operated by lifting the spider
and all of the valves simultaneously to regulate the strength and velocity of the air
currents.
M is a feeding disk of any ordinary sort attached to and carried by the fan
shaft G.
Nn is a feeder tube of which the outer ring n is adjustable, by link and lever n¹ n²
relatively to the disk M, as is customary in that kind of feeder and carries at its lower
end, an outward projecting flange which practically closes the space between the
feeder tube and the lower end of the innermost ring j.

page_text: O is a hopper and o a delivery spout.
This machine may be operated as follows:
The fan and foeder being put in operation by a belt from any suitable motor to the
pulley on the upper end of the fan shaft, material fed in through spout N1 is delivered
by the feeding dise M in a sort of spray, and falls thence outside of the rings K K
where it is separated by the air currents which move upward substantially as indicated
by the arrows in Fig. 1, the strength of the air current being regulated by the valves
as has been explained. These air currents are drawn up into the eye of the fan
carrying with them such of the lighter finer particles as have been taken out by such
air currents, and thence through the mouth of the fan into the annular chamber.
between the shells B B' C.
The material thus delivered through the mouth of the fan is discharged at the
bottom of the shell B, the air going up over the upper end of the inner shell E and
thence downward to the lower edge of the aspirator shell, and thence through the
falling sheet of material which is distributed by the disc of the feeder.
Thus it will be seen that the air current which is put in motion by the fan, follows
substantially the same serpentine course round and round again through the machine,
separating the material into different grades according to its specific gravity; the
finer particles being removed from the air current within the shell B B by centrifugal
action.
While under many circumstances, said separation of the impurities and fine particles
will be made within an annular space between these shells of the proportion indicated
in Fig. 1, yet it may be sometimes found advantageous to make the shell B B¹ much
larger in proportion to the others than is shewn in the drawings; or to relatively
reduce the horizontal diameters of the shell CE.
The shells of the machine together with the rings which have been referred to may
be made of sheet metal or any other suitable material such as is commonly used in
machines of this general character. Under ordinary circumstances, I propose to keep
the deck or cover I¹ in place on the top of the machine and use the same air over
and over again; but I do not wish to be limited to such operation, because it will
sometimes be found advantageous to remove the cover wholly or in part, letting more
or less of the air escape after it has been freed from dust or fine particles, particularly
when it is desired to dry or cool the material being acted upon; as it will be readily
understood without further explanation. As I have described the machine and its
operation it may be used as a middlings purifier, but it is evident that it may be used
in substantially the same way for the purpose of dividing finely pulverised material
of various Sorts into different grades irrespective of any function of purification. I
also propose to remove the aspirating apparatus and fan and substitute a fan shewn in
Fig. 8 with a lower imperforate head P and spout R leading from the eye of the fan
to, for instance, a middlings purifier. The lower end of the fan shaft G¹ may be
supported in a down hanger Q; the upper side of the ring D being practically
unobstructed around its entire periphery between the brackets ii which support the
fan so that air having been freed from dust within the separating chamber may
escape from the machine as indicated by the arrows in said Fig. 8.
In Fig. 9, the shell E is omitted, so that the separating chamber b consists of a
practically unbroken space between the outer shell B B₁ and the shell C and the
aspirator the upper fan head H' extending entirely across the shell B'; the lower
fan head closing the annular space between the shell C and the upper end of the
shell of the aspirator, except that the feed spout passes through the fan heads.
It will of course be understood that the connection or supports of the bearing or
step at the foot of the fan shaft in Fig. 1 should by preference be of such nature
that they can be removed from the machine with the fan and the aspirator without
difficulty or fracturing any part thereof when such connections are used, although
under ordinary circumstances, a sleeve bearing like that at g will be sufficient if care
be taken to provide a strong head to the fan and firm attachments connecting the
bearings with such head.

page_text: Of course the ties or other connections between the flaring rings K and the con-
verging rings should be of such character. as will permit a free passage for..the
middlings; or the rings K may be attached. to or carried by the fan shaft.
It will be seen that after the air current leaves the aspirator and enters the
separating chamber, its velocity is greatly reduced by reason of the separating
chamber being of so large size or capacity relatively to the aspirating chamber; one
result being that material which is taken out by the air current will fall to the bottom
of the separating chamber irrespective of any effect of centrifugal action.
This becomes a quite important feature in the operation of the machine especially
when it is being used for separating particles or small granular substances which are
so heavy that they can only be taken from the the mass by a quite strong air current
as for instance when the machine is being used for the grading or cleaning of grain,
it being well known that it is frequently desirable to separate shrivelled; broken grain
and other things from grain as it is ordinarily received into a mill, elevator, or other
place of storage.
፡፡
I also propose to use the machine for the separating of the breaks of wheat from
grinding rolls or other reducing machinery, such operation being usually known as
scalping; and in which this machine can be advantageously used, because among other
things, such scalping" can be effected with but little abrasion of the broken wheat
or partially reduced wheat, whereby there is effected a marked saving in the amount
of fine flour or dust produced by the frequent reparations which are involved in the
system of milling which is commonly known as gradual reduction.
While I have shewn a form of aspirator and a form of separating chamber which
I regard as the best now known to me for the carrying out of my invention, I do
not wish to be limited, thereby, because many modifications therein can be readily
made by a skilled mechanic who is familiar with the various forms of aspirators and
separating chambers which are used in the arts to which my invention pertains;
particularly that part of it which relates to the process or method of effecting the
separations by the repeated use of substantially the same body of air which
over and over again within the machine and without any admixture of impurities
which may be suspended in the air of the mill or other place where the machine is
located.
used
Having particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. In a separating machine, the combination with the aspirating chamber and an
external concentric separating chamber, with means for discharging air from the
aspirating chamber into the separating chamber, substantially as set forth.
2. In a separating machine, the combination of an aspirating chamber, a hopper for
the middlings below the aspirator, a separating chamber surrounding the aspirating
chamber, and an opening for the discharge of material taken out by the air current,
substantially as set forth:
3. In a separating machine, an aspirating chamber and a dust separating chamber
surrounding the aspirating chamber, in combination with a fan which takes air and
light material from the aspirator and delivers it to the separating chamber, these parts
being enclosed within an outer shell or casing, substantially a set forth.
4. In a separating machine, the combination of an aspirator, a surrounding
separating chamber, a fan and air passages connecting the aspirating chamber, the
fan and the dust separating chamber, whereby air currents are caused to pass
continuously through and within the machine, substantially as set forth."
A separating chamber in combination with a fan arranged within the circum-
ference of the chamber and delivering a dust laden air current against the inner wall
of said chamber, and an air outlet for the purified air by the side of the fan,
substantially as set forth.
6. In a separating machine, the combination with a vortex chamber, of a fan within
the circumference of the said chamber, a shell of less diameter arranged 'substantially

page_text: concentric to the walls of said chamber, and a flange depending from the upper part
of the machine within the said inner shell, substantially as set forth.
7. In a separating machine, the combination with the vortex chamber, of a removable
aspirator arranged within said chamber, and a removable fan above the aspirator,
substantially as set forth.
8. In a separating machine, the combination of the outer funnel-shaped shell B B',
the inner shells CE concentric thereto, the aspirator shell also concentric thereto,
and the fan connected at its eye to the upper end of the aspirator, substantially as
set forth.
9. In a separating machine, the combination of an aspirating chamber, a separating
chamber which is enclosed on all sides and means substantially as described for
producing a continuous air current through the material to be purified or separated,
substantially as set forth.
10. In a separating machine, the combination of an enclosed separating chamber,
an aspirator arranged within the separating chamber, and a fan for producing air
currents through the aspirator and for producing a vortex within the separating
chamber, substantially as set forth.
11. The herein described method of separating finely pulverised material into
different grades according to their specific gravity, the same consisting essentially in
passing the same current of air through the material inside the aspirating chamber
and around the outside of the aspirating chamber within the wall of the separating
chamber, substantially as set forth.
12. The herein described process of separating material into different grades of
fineness, the same consisting essentially of passing a current of air through the
material to be divided, discharging the air current and the material taken out by it
into a separating chamber of greater capacity than the aspirating chamber in which
the material taken out by the air current falls to the bottom by gravity and
subsequently returning the air to the aspirating chamber, substantially as set forth.
Dated this 10th day of September 1888.
ABEL & IMRAY,
Agents for the Applicant.