Improved means applicable for use in Proportioning and Mixing Finely Divided or Powdered Substances.
Year: 1899

page_text: Date of Application, 15th July, 1899
Complete Specification Left, 17th Apr., 1900-Accepted, 14th July, 1900
Improved means applicable for use in Proportioning and Mixing
Finely Divided or Powdered Substances.
I, GEORGE GATTON MELHUISH HARDINGHAM, of Clun House, Surrey Street, in
the County of London, Civil Engineer and Chartered Patent Agent, do hereby.
declare the nature of this invention (a communication from abroad from Augusto
Musciacco, of Brindisi, in the Kingdom of Italy,) to be as follows:-
This invention relates to apparatus for mixing finely divided or powdered sub-
stances in pre-determined proportions; same being applicable for use in the
preparation of mixtures of various kinds, such as the materials for artificial
manures, coloured tiles, medicines and the like.
Apparatus for proportioning powdered substances and mixing them together
according to this invention consists essentially of a battery of tubs into which
the powders to be mixed are fed and whereof the number is equal to that of
the number of powders to be mixed. The several tubs are mounted above a
mixing apparatus and are each divided vertically into two compartments and
provided with appliances whereby the powders are conducted to the mixing
apparatus, without previous compression or weighing, in a stream, which assumes
a constant prismatic form in section; the stream being led towards the mixer at
a uniform speed The section of the stream and the rate of feed vary in the
case of each tub in accordance with the pre-determined proportions in which the
several powders are required to be mixed. The streams of powder from the
several tubs meet in a hopper, and pass therethrough into the mixer in a single
stream, which, upon entering the mixer, is broken up by means of arms or beaters
carried by shafts which preferably revolve in the same direction. Thus the
stream from the hopper becomes thoroughly mixed while being carried through
the air, and is ultimately collected in sacks or other receptacles, in the condition
of a perfectly homongeneous powder.
Assuming the apparatus, to be applied, by way of example, to the mixing of
powders of four different qualities in pre-determined proportions, the several
powders to be proportioned and mixed are placed in the compartment of the tub
which in working is situate farthest from the main centre of the apparatus.
The floor or bottom of each of the tubs is caused to revolve about its pivot
by means of a toothed bevel ring with which the floor is furnished and with which
meshes a bevel pinion driven from the motor shaft. The partition in each tub
consists of two moveable plates whereof one may be termed the gate and the other
the blade.
The motion of the revolving floor is such as to cause the powders to pass from
the one to the other compartment through an orifice formed by the lower edge
of the gate and the revolving floor. In order to enable the operator to determine
the proportions of the mixture at will, the speed of rotation of each of the
revolving floors may be varied by the employment of interchangeable gearing,

page_text: while the extent of the orifice for the passage of the powder from one compart-
ment of the tub to the other may be varied, during the working of the apparatus,
by connecting to the upper portion of the gate an arm, the gate being loosely
mounted upon a crank-shaft which turns on journals in the sides of the tub. By
turning a screw, whereof the upper extremity supports the outer end of the arm, the
crank-shaft is caused to turn on its journals and thereby effect the desired
variation in the degree or extent of the orifice. This height may be read off,
from time to time, from a graduated scale secured to the outer wall of the tub.
To prevent powders which have a certain tendency to coagulate from adhering
to the surface of the gate, the latter at its lower edge rests against a pivoted
curved or bent bar which is vibrated by means of a ratchet-pinion which enters
a hood- or scoop-shaped part of the gate and which partakes of the rotary motion
of the revolving floor. The ratchet-pinion works against a nose or tappet on
the bar and imparts a vibratory motion thereto which in turn is transmitted to
the lower edge of the gate; any matter that may have adhered thereto being
shaken off. Any powder which may find its way between the tub and the
revolving floor is conducted, by way of perforations in the floor, to a receptacle
arranged beneath the said floor; the said powder being collected by means of a
rotatably mounted brush and swept towards an aperture whence it falls into sacks
or other receptacles.
To ensure uniformity in working and accuracy in the proportioning of the
powders, it is necessary that the mass of powder in each tub should not be
allowed to fall below a pre-determined level, and, with this object, the blade
portion of the partition is hung at its upper end upon an extension of the crank-
shaft, the said blade being hereby caused to move in unison with the gate portion
when the height of the latter is varied as before explained for the purpose of
varying the extent of the orifice beneath the partition. The said blade is con-
nected with an arm situate outside the tub; the said arm being capable of regula-
tion in relation to the blade and carrying an adjustable counter-weight and a
gong.
Upon the level of the powder in the compartment of the tub falling below the
pre-determined limit, the pressure which it had previously exerted upon the sur-
face of the blade is in consequence removed. The blade is thereupon over-
balanced by the weighted arm, the latter, in falling, carrying the gong against a
revolving pulley, thereby ringing the gong and calling the attention of the
operator to the fact that the tub is about to become empty.
The closure of the junction of the gate with the blade may be effected by means
of canvas, while any impurities on the charging platforms may be prevented from
gaining access to the tubs by means of canvas attached above the gate and blade.
So soon as the powder arrives in the other compartment of the tub it is con-
veyed by an Archimedean screw to a central hopper.
Any adherence of the powder to the screw is obviated by causing the latter
to be swept or scraped from end to end by means of scraping devices carried by
an endless chain operated by the said screw.
Should any of the powders to be proportioned and mixed show a tendency to
cake, the casing pertaining to the feed screws which convey the powders to the
central hopper may be provided with the following appliances for pulverising
or breaking up such formations
A slotted connecting rod or link pivoted in the framing transmits a reciprocat-
ing motion to a bar connected with the slotted rod; the said bar being furnished
with arms or scrapers whereof the carrier is pivoted to the said bar and bifur-
cated so as to embrace the spindle pertaining to the feed-screw. The said
scrapers vibrate in front of the delivery end of the feed-screw casing and effec-
tually intercept and break up any lumps before the same reach the central hopper.
The slotted link is operated by spur pinions and a crank pin which engages with
the link.
An oscillatory movement may also be imparted to the central hopper by a

page_text: similar arrangement of slotted link or rod, the powders passing through the
hopper being thereby prevented from adhering to the walls of such hopper.
From the hopper, the powder drops into the mixing apparatus proper. This
consists of a casing enclosing two vertically arranged shafts which revolve at a
high rate of speed. Each of these shafts is furnished at intervals from end to
end with several radiating horizontal arms or cross-bars. The arms are some-
what shorter than the distance between the two shafts and are arranged thereon
in sets each set being disposed at a predetermined angle to, or slightly in advance
of, that of the next adjacent set; the effect of the arrangement being that when
the several sets are projected in plan, that is to say, looking in the direction of
the axis of the shaft, they cover the whole of the surface of a circumscribed
polygon. The ends of the arms of each set are connected by tie-rods. The sets
of arms on the one shaft alternate with those on the other shaft; that is to say,
the set on the one shaft comes about midway of two succeeding sets on the other
shaft. The stream of powder which descends from the hopper precisely midway
of the shafts consequently receives in its descent a series of rapidly repeating
strokes which (supposing the two shafts to be revolving in the same direction)
are imparted in opposite directions. This completes the mixing operation and
renders the mixture perfectly homogeneous by dividing the stream of different
powders and effecting their commixtion; the mixture being thereupon collected
in sacks arranged beneath the mixing apparatus.
The driving gear employed may be varied to suit requirements. Provision
should however be made for varying the speed of the several parts of the
mechanism in accordance with the varying proportions of the powders to be mixed.
This latter is accomplished, not merely by varying the aperture under the gate―
which may be adjusted while the machine is in operation-but, where more sub-
stantial variations are required, some of the wheels and pulleys used in operating
the various appliances may be removed and replaced by others during the stoppage
of the machine; thereby varying the rate at which motion is imparted to the
revolving bottoms or conveyor screws. The speed of the mixer-arms may be
constant.
T
1511
A T 1 1000
Improved means applicable for use in Proportioning and Mixing
Finely Divided or Powdered Substances.
I, GEORGE GATTON MELHUISH HARDINGHAM, of Clun House, Surrey Street, in
the County of London, Civil Engineer and Chartered Patent Agent, do hereby
declare the nature of this invention (a communication from abroad from Augusto
Musciacco, of Brindisi, in the Kingdom of Italy,) and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement:―
This invention relates to apparatus for mixing finely-divided or powdered sub-
stances in predetermined proportions; same being applicable for use in the
preparation of mixtures of various kinds, such as the materials for artificial
manures, coloured tiles, medicines and the like.
Apparatus for proportioning powdered substances and mixing them together
according to this invention consists essentially of a battery of tubs into which
the powders to be mixed are fed and whereof the number is equal to that of
the number of powders to be mixed. The several tubs are mounted above a

page_text: mixing apparatus and are each divided vertically into two compartments and
provided with appliances whereby the powders are conducted to the mixing
apparatus, without previous compression or weighing, in a stream, which assumes
a constant prismatic form in section; the stream being fed towards the mixer at
a uniform pace. The section of the stream and the rate of feed vary in the case
of each tub in accordance with the predetermined proportion in which the several
powders are required to be mixed. The streams of powder from the several tubs
meet in a hopper, and pass therethrough into the mixer in a single stream,
which, upon entering the mixer, is broken up by means of arms or beaters carried
by shafts which preferably revolve in the same direction. Thus the stream from
the hopper becomes thoroughly mixed while being carried through the air, and
is ultimately collected in sacks or other receptacles, in the condition of a perfectly
homogeneous powder.
In the accompanying drawings, which illustrate one mode of carrying out the
invention, Fig. 1 is a plan of the apparatus; the platforms whereon the operator
stands being partially broken away. Fig. 2 is a transverse section taken on the
line A Bin Fig. 1. Fig. 3 is a view partly in side elevation and partly in
longitudinal section on the line C-D in Fig. 1. Figs 4 to 10 illustrate various
details of construction hereinafter more particularly referred to.
Assuming the apparatus to be applied, by way of example, to the mixing of
powders of four different qualities in predetermined proportions, the several
powders to be proportioned and mixed are placed in the one or the other of the
compartments 7, 8 of the tub 2 which, in working, is situate farthest from the
main centre of the apparatus and which in the present example is the compart-
ment 7. The floor or bottom 3 of each tub is caused to revolve about its pivot 4
by means of a toothed bevel ring 5 with which the floor is furnished and withi
which ring meshes a bevel pinion 6 driven from the motor shaft. The partition
which divides the compartments 7 and 8 in each tub consists of two moveable
plates 9 and 10 whereof one, 9, may be termed the gate and the other, 10, the
blade. The floor 3 in revolving causes the powders to pass from the compart-
ment 7 through an orifice 11 (Figs. 2 and 3), formed by the lower edge of the
gate 9 and the revolving floor into the compartment 8. In order to enable the
operator to determine the proportions of the mixture at will, the speed of rota-
tion of each of the revolving floors may be varied by the employment of inter-
changeable gearing, while the extent of the orifice 11 for the passage of the
powder from one compartment of the tub to the other may be varied, during the
working of the apparatus; by connecting to the upper portion of the gate 9 an
arm 12 (Figs. 2 and 7). the gate being loosely mounted upon a crank-shaft 13
which turns on journals 14 in the sides of the tub. By turning a screw 15,
whereof the upper extremity supports the outer end of the arm 12, the crank-
shaft 13 is caused to turn on its journals 14 as shown in dotted lines in Fig. 7
and thereby effect the desired variation in the degree or extent of the orifice 11.
This height may be read off, from time to time, from a graduated scale 16
(Fig. 2) secured to the outer wall of the tub 2.
To prevent the different powders which have a certain tendency to coagulate
from adhering to the surface of the gate 9, the latter at its lower edge rests
against a curved or bent bar 17 which is pivoted at 18 (see Figs. 2. 3 and 10)
and vibrated by means of a ratchet-pinion 20 which enters a hood- or scoop-
shaped part 21 of the gate 9 and which partakes of the rotary motion of the
revolving floor 3. The ratchet-pinion works against a nose or tappet 19 on the
bar 17 and imparts a vibratory motion thereto which in turn is transmitted to
the lower edge of the gate 9: any matter that may have adhered thereto being
shaken off. Any powder which may find its way between the tub and the revolv-
ing floor, .e., through the joint 22 (Figs. 2 and 3) is conducted, by way of per-
forations 23, to a receptacle 24 arranged beneath the said floor: the said powder
being collected by means of a rotatably mounted brush 25 and swept towards an
aperture 26 whence it falls into sacks or other receptacles.

page_text: To ensure uniformity in working and accuracy in the proportioning of the
powders, it is necessary that the mass of powder in each tub should not be allowed
to fall below a predetermined level, and, with this object, the blade portion 10
of the partition pertaining to each tub 2 is hung at its upper end upon an
extension of the crank-shaft 13 (Figs. 4 and 5), the said blade being hereby caused
to move in unison with the gate portion 9 when the height of the latter is varied
as before explained for the purpose of varying the extent of the orifice beneath
the partition. The said blade 10 is connected with an arm 27 situate outside the
tub 2; the said arm being capable of regulation in relation to the blade and
carrying an adjustable counter-weight 29 and a gong 30.
Upon the level of the powder in the compartment 7 of the tub falling below
the predetermined limit, the pressure which it had previously exerted upon the
surface of the blade 10 is in consequence removed. The blade is thereupon over-
balanced by the weighted arm 27, the latter, in falling, carrying the gong 30
against a revolving pulley 28, thereby sounding the gong and calling the attention
of the operator to the fact that the tub is about to become empty.
The closure of the junction of the gate 9 with the blade 10, along the line 32,
may be effected by means of canvas 31, and the powder may be prevented from
gaining access to the compartment 8 of the tub by means of a canvas flap 33
attached to the platform 1 in such a manner as to hang over the gate 9 and
the canvas 31.
So soon as the powder arrives in the compartment 8 of the tub it is conveyed
by an Archimedian screw 34 to a central hopper 35. Any adherence of the
powder to the screw is obviated by causing the latter to be swept or scraped from
end to end by means of scraping devices carried by an endless chain 36 (see
Fig. 6) operated by the said screw.
Should any of the powders to be proportioned and mixed show a tendency to
cake, the casing pertaining to the feed screws which convey the powders to the
central hopper 35 may be provided with the following appliances for pulverising
or breaking up such formations (see Figs. 1 and 8, the latter being a section
on the line FF in the former figure). A slotted connecting rod or link 37
pivoted at 38 transmits a reciprocating motion to a bar 40 connected at 41 with
the slotted rod 37; the said bar being furnished with arms or scrapers 42, 42,
whose carrier is pivoted at 44 to the said bar 40 and bifurcated so as to embrace
the spindle 45 pertaining to the feed-screw 34 (Fig. 8). The said scrapers
vibrate in front of the delivery end of the feed-screw casing 43 and effectually
intercept and break up any lumps before the same reach the central hopper. The
slotted link 37 is operated by spur pinions and a crank pin which engages with
the link.
An oscillatory movement may also he imparted to the central hopper 35 by
means of the link or rod 46 which is pivoted at 47, the powders passing through
the hopper being thereby prevented from adhering to the walls of such hopper.
From the hopper, the powder drops into the mixing apparatus proper.
This
consists of a casing 48 enclosing two vertically arranged shafts 49, 60, which
revolve at a high rate of speed. Each of these shafts is furnished at intervals
from end to end with several radiating horizontal arms or cross-bars. In the
drawing the shaft 49 is represented as carrying the arms 50 to 59 and the shaft 60
the arms 61 to 70. The arms are somewhat shorter than the distance between
the circumferences of the two shafts and are arranged thereon in sets of say
eight arms each set of arms being disposed at a predetermined angle to, or slightly
in advance of, that of the next adjacent set; the effect of the arrangement being
that, when the several sets are projected in plan, that is to say, looking in the
direction of the axis of the shaft (see Fig. 9), they cover the whole, or practically
the whole, of the surface of a circumscribed polygon. The ends of the arms of
each set are connected by tie-rods. The sets of arms on the one shaft, 49, alter-
nate with those on the other shaft, 60: that is to say, the set on the one shaft
comes about midway of two succeeding sets on the other shaft. The stream of

page_text: powder which descends from the hopper 35 precisely midway of the shafts 49
and 60 consequently receives in its descent a series of rapidly repeating sirokes
which (supposing the two shafts to be revolving in the same direction) are
imparted in opposite directions. This completes the mixing operation and renders
the mixture perfectly homogeneous by dividing the stream of different powders
and effecting their commixtion, the mixture being thereupon collected in sacks
arranged beneath the casing 48 of the mixing apparatus.
The driving gear employed will be readily understood from the drawings and
needs no description. It may be varied according to requirements, but provision
should be made for varying the speed of the several parts of the mechanism in
accordance with the varying proportions of the powders to be mixed. This latter
is accomplished, not merely by varying the aperture under the gate-which may
be adjusted while the machine is in operation-but, where more substantial
variations are required some of the wheels and pulleys used in operating the
various appliances may be removed and replaced by others of different sizes or
proportions during the stoppage of the machine; thereby varying the rate at
which motion is imparted to the revolving bottoms or conveyer screws.
The speed
of the mixer-arms may be constant.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I claim:-
-
1. The herein described means applicable for use in proportioning and mixing
finely-divided or powdered substances, same comprising a battery of tubs arranged
about a central hopper and each adapted to deliver the powder in a regulated
quantity, feeding devices for conveying the powders from the several tubs to the
central hopper, and a mixing device arranged beneath the said central hopper.
2. In apparatus for use in proportioning and mixing finely-divided or powdered
substances, a tub for receiving and delivering the powder constructed or operating
substantially as herein described and having a revolving bottom and a partition
consisting of a pivotally mounted blade and a gate; the blade effecting the sound-
ing of a gong or other alarm upon the level of the powder in the tub sinking
to a predetermined level.
3. In apparatus for use in proportioning and mixing finely-divided or powdered
substances, a partitioned tub for the reception and delivery of the powder whereof
the gate is furnished with means for imparting an oscillatory movement thereto,
substantially as and for the purposes specified.
4. In apparatus for use in proportioning and mixing finely-divided or powdered
substances, an oscillatory hopper for receiving the several powders from the sur-
rounding tubs, constructed or operating substantially as and for the purposes
specified.
5. In apparatus for use in proportioning and mixing finely-divided or powdered
substances, the employment of scrapers in conjunction with the feeding devices
or conveyors for conveying the powders from the several tubs, substantially as
and for the purposes specified.
6. In apparatus of the character herein referred to, the herein described mixing
device consisting of a pair of revolving shafts each furnished with a number of
arms or beaters whereof the set of arms on the one shaft enter between the arms
pertaining to the set on the other shaft; the blending or incorporation of the
several powdered substances being hereby rendered complete.
7. For use in proportioning and mixing finely-divided or powdered substances,
apparatus constructed or operating substantially as described with reference to
the accompanying drawings.