Improvements in Mixing, Kneading, and other analogous Machines in which Blades or Mixers are Employed.
Year: 1895

page_text: Date of Application, 26th Feb., 1895-Accepted, 26th Feb., 1896
COMPLETE SPECIFICATION.
Improvements in Mixing, Kneading, and other analogous Machines
in which Blades or Mixers are Employed.
I PAUL PFLEIDERER, of Throssel House, Selsden Road, West Norwood,
London S.E., Engineer, 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 statement :-
This invention has for its object to improve and modify the system, or funda-
mental principle, of the construction, arrangement, and operation, of the blades or
mixers of machines for mixing, kneading or otherwise treating all kinds of materials,
including dough and other plastic or semi-fluid masses, and more particularly of my
well known "Universal" and "Single blade" kneading and mixing machine.
The invention consists, first, in providing the blades or mixers with perimetrical
gaps of large size, and unequal and unsymmetrical dimensions, in order to afford
clearance for the material being worked and to facilitate its working.
The invention also consists in a pair of blades, (with equal or unequal gaps)
arranged out of aligument, transversely, in the mixer box or trough, and having
end scrapers, or an endwise movement. And under this second part of my
invention are included a number of modifications for accomplishing the same
purpose, namely, the working of the mass throughout the box or trough.
The third part of my invention consists in a pair of blades mounted in a box or
trough and operated independently or separately.
And in order that my said inventiou may be particularly described, and ascer-
tained, reference is hereby made to the accompanying drawings, in which similar
letters of reference indicate corresponding parts.
Fig. 1. is a plan view of a machine showing one form of my invention.
Figs. 2, 3, and 4, are perspective views of three several forms of blades; the
Figures 1, 2, 3 and 4, showing by dotted lines the alterations in the construction of
the gaps over the old forms.
Fig. 5 is a perspective view of a mixing machine showing an old form of blades
with end scrapers at one end only of each blade.
Fig. 6 is a perspective view of a mixing machine showing the new form of blades
with scrapers at both ends of both blades.
Fig. 7 is a perspective view of a machine having axially slidable blades for
accomplishing the same purpose as the scrapers in Figs. 5 and 6.
Fig. S is a plan view of a mixer showing a modification in the arrangement of the
gaps.
Fig. 9 is a plan view of portions of a machine, showing each blade having a single
large gap, the gaps being at opposite ends of the respective blades.
Fig. 10 is a plan view of a mixer having means for independently operating the
two blades.
Figs. 11, 12, and 13, are perspective views of skeleton, perforated, or open-work
blades, constructed with large and unequal gaps, the dotted lines representing the
old forms.
In Fig. 1, a is a box or trough, of any approved construction, and adapted to
contain the plastic, or other mass, to be treated by the blades b b. These blades
are mounted upon shafts c, c, having bearings in the box; and said shafts may be
geared together by differential gearing d, d, both of the shafts being constructed so
D937

page_text: Fig. 8
that either may he used as the driving shaft. For reasons hereinbefore indicated
and hereinafter stated at large, I make gaps e, f, in the perimeters of these blades,
of large size, and unequal and u symmetrical dimensions. These gaps may be made
on opposite sides of the axial centres of the blades, and at opposite ends, and
similar gaps may be at similar ends, as shown in Fig. : or they may be at
pposite ends of the respective blades, as shown
and, as also shown in
Fig. 8 and in Fig. 9, the gaps may extend across the axial centres. Fig. 2 shows
a blade made separate from its shaft, and having arms at its ends, which are
provided with holes g', g', which are aligned with a hole in the body of the blade
to receive a shaft. Fig. 3 shows a blade cast with its shaft, or otherwise perma-
nently applied thereto; and Fig. 4 shows a blade, similar to that shown in
Fig. 3, but with a hub 72, by means of which it may be applied to a shaft.
Figures 1 to 4, the new and improved construction of gaps is shown by the full
lines, while the old construction is indicated by the broken lines. All these blades,
and also all those hereinafter described, are constructed in the preferred form as
segmental ellipses, generated from an oblique section of a cylinder; but I do not
wish to he understood as limiting my invention with any degree of mathematical or
geometrical exactitude to that figure.
In
In some cases it may he desirable to use a trough or box of greater length than
the extreme length of the blades, and in order to lengthen out the blades so as
to reach and act upon the whole contents of the box, I may add scrapers at
opposite ends of the respective blades, as shown in Fig. 5, thereby throwing the
blades out of transverse alignment, and insuring the desired action upon the whole
mass of material being treated. Or, as shown in Fig. 6, the blades may be arranged
out of alignment, and scrapers h, h, of different widths in the direction of the axis
of rotation, may be arranged alternatively at opposite ends of each blade. These
scrapers may be loosely or fixedly arranged upon the shafts of the blades.
A similar result may be obtained by mounting the blades upon their shafts so as
to rotate therewith, and also to move longitudinally thereon, as illustrated in Fig. 7.
In the case of the constructions shown in Figs. 56, and 7 the old or the new con-
structions of gapped blades may be used, the old being shown in Figs. 5 and 7, and
the new in Fig. 6, for illustration.
It is within my invention, also, to use a single large gap in each blade, as shown
in Fig. 9, wherein the gap el, extends from the hub or arm at one end, and nearly to
the arm or to the hub at the other end, and across the axial centre of the blade.
One of the simplest constructions of my machine, which is most suitable for
domestic use, and for all purposes which require greatest simplicity and cheapness,
coupled with one or other or all of the advantages incident to my invention,-
consists in one or other of my blades, or any other suitable blade, revolving in a
trough or box of greater length than the blades, so that the blades may have a
longitudinal movement therein, by virtue of their shafts being set in bearings so
as not only to revolve but to slide longitudinally; and in this particular, this form
of my invention is the alternative of the construction shown in Fig. 7, where the
blades slide on their shafts instead of the shafts sliding in their bearings. The
movements of the blades, in either case, serve to enable the blades periodically to
scrape the sides and bottom of the trough in all parts. Such blades are combined
with one or more gears or pinions i, j, Fig. 10, of sufficient width (axially) driven
by a hand-crank k, or fly wheel 7, or both or by a suitable belt from a line shaft
where convenient. In this arrangement, the blades, as it were, find their positions
of least resistance automatically; or the operators find them out by feeling the
resistance while they have it, at the same time, in their power and control, to
move the blades axially as required, for scraping the sides or walls of the trough
or mixing box; all wheel gearing for purposes of mechanically performing such
lateral sliding being dispensed with. If one of the spur wheels or pinions ij be
removed, power shaft through belts or other gear, or one man with his two hands
can drive both blades in either direction at different or equal speeds by handles k
or fly wheels / on each shaft, or a number of persons or other motors can drive

page_text: simultaneously. The blades should be run towards or from each other, at different
speeds, so far as is practicable and convenient, and they may be driven at the same
time some by power others by hand.
Figs. 11, 12 and 13 show three several forms of perforated, or open-work,-or
skeleton-blades, the full lines indicating my improved gapping, and the dotted or
broken lines indicating the old form of gapping; but, while for some purposes, the
perforated blades may be desirable, I believe the best results will be attained by
the imperforate and gapped blades.
From Fig. I it will be seen that if the machine were driven in one direction only,
the material would gradually be propelled toward, and heaped up near one or other
of the sides or ends according to the direction of rotation of the blades. This result
may be utilized for emptying and clearing the machine intermittently or continuously;
but, when preferred, this heaping up of the material may be obviated by driving or
running the blades alternately in opposite directions. Fig. 8 shows a form of my
machine suitably adapted for emptying and clearing.
I sometimes make openings in the sides of the machine, at points diagonally
opposite the smaller gaps i, e.at the ends which are scraped by the arms nearest
to the large gaps of the blades. If the handle or driving pulley is revolved in one
direction, the material is thereby heaped up and propelled towards the same
openings if the motion is reversed the material is withdrawn, and a certain
amount of suction, or tendency to draw the material inward through the openings
is set up.
Any well known feed or delivery rollers, or other converging or
propelling mechanism, combined with or applied to the opening, and operated by the
same shaft which drives the blades, will assist the process of filling and emptying or
clearing.
The resultants of similar operations are utilised in squeezing and squirting
the material in or out of the container of the machine, through any suitably formed
nozzles, spouts, or dies, which may he readily applied to the openings.
The latter may also be fitted with cutting off valves, sluice gates, or doors, and
communication with any vessel or with one or more additional machines, may be
established; which enables the operator to subject the material under operation to
a large variety of treatments, by merely setting the reversing gear or operating
handle or pulleys to move the apparatus in one or other direction, no deviation from
the forms of the unsymmetrically gapped kneading and mixing blades herein
described being necessary, such blades being those best adapted for their herein
described functions, irrespective of their propelling properties, which are quite
incidental, but which I make effective use of in so simple a mauner.
Although I have shown and described my invention as used in connection with a
two-blade machine, I wish it to be understood that my invention covers and includes
the use of one or more blades, as may be required for the work to be done.
In all the blades these two main and essential features are present, namely, an
increased accessibility of parts, and a reduction to a minimum of the more or less
objectionable transverse solid portion.
4. The
The main advantages of my invention are, 1. The possibility of increasing the
capacity of the trough and thereby treating a larger quantity of material with equal
efficiency and thoroughness, without increasing the driving power required for the
machine. 2. The equalisation of the resistance offered during the various phases
of the mixing and kneading operation. 3. The increased facility and accessibility
for cleaning and controlling the working parts and bearing surfaces.
possibility of continuous or intermittent working and discharging, without any
additional screw or other propellers, and even without the necessity in every case
of tilting the trough, by the mere action of the mixing blades, and without having
to impair, for purposes of emptying, their shape as it is best adapted for mixing
and kneading or crushing and disintegrating. 5. The absolute freedom from
danger to life and limb in consequence of the absence, from the domestic machine
particularly, of all wheel gearing or mechanism of any kind. 6. The possibility of
avoiding all friction between the sides or walls of the mixing box and those of the

page_text: blades during the phases of the incorporating or kneading process, when the
requisite power is at its maximum.
I wish it to be understood that I do not limit my invention to its use with plastic,
semi-fluid or analogous masses, since it is obvious that it may also be used for
mixing kneading, crushing, grinding and pulping and otherwise treating dry or
other pulverulent matter, liquids &c., in the same manner, but with enhanced
efficiency, as my "Universal” kneading and mixing machine is being extensively
used already.
Having now 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. A blade for mixing, kneading and such like machines, having its perimeter
formed with a deep gap, extending transversely inward towards the axial centre of
the blade, and beginning at or near one end, ending short of the other end; the
full width of the stock or body of the blade being preserved at the ungapped
portion substantially as hereinbefore described and illustrated by the drawings..
2. A blade for mixing, kneading and kindred machines, having its perimeter
supplied with gaps of large size and unequal and unsymmetrical dimensions, sub-
stantially as hereinbefore described and illustrated by the drawings.
3. A blade for mixing, kneading and kindred machines, having its perimeter
supplied with gaps of large size and unequal and unsymmetrical dimensions, and
arranged upon opposite sides of the axial centre of the blade, and at opposite
ends of such blade, substantially as herein before described and illustrated by the
drawings.
4. A machine for mixing, kneading and other purposes, comprising a pair of
rotary blades having perimetrical gaps of large size and unequal and unsymmetrical
dimensions, arranged at opposite sides and ends of the respective blades, the gaps
alternating as to size at opposite ends of the respective blades, substantially as
herein before described and illustrated by the drawings.
5. In a machine for mixing, kneading and kindred purposes, the combination with
a pair of perimetrically gapped blades, a mixing trough or box of greater length
than the blades so as to leave spaces between the ends of the trough and the
blades, and means to bring the material in such end spaces within the influence
of the blades, substantially as hereinbefore described and illustrated by the
drawings.
6. In a machine for mixing, kneading and kindred purposes, the combination
with a pair of perimetrically gapped blades, a mixing trough or box of greater
length than the blades so as to leave spaces between the ends of the trough and the
blades, and shafts for such blades having longitudinal movement in their bearings
in order thereby to bring the material in such end spaces within the influence of
the blades, substantially as herein before described and illustrated by the drawings.
7. In a machine for mixing, kneading and kindred purposes, the combination
with a mixing trough, box, or container, of a number of mixing or kneading blades
having perimetrical gaps of large size and unequal and unsymmetrical dimensions,
and differential driving mechanism, such as toothed gearing, for such blades, the
gaps in, and the varying speeds of the blades, serving to produce in action an
increased irregularity in the periodical recurrence of the mixing or kneading
operations, and the occasional great resistance of the material under treatment
being thereby correspondingly reduced so as to economise the requisite motive
power, substantially as hereinbefore described and illustrated by the drawings.
8. A blade for mixing kneading and such like machines, having its perimeter
supplied with a deep gap, extending transversely inward toward the axial centre
of the blade and beginning at or near one end and ending short of the other end,
the opposite edge of the blade being unsymmetrical with relation to the gapped
edge substantially as hereinbefore described and illustrated by the drawings.
9. In a machine for kneading, mixing, crushing, grinding and pulping the

page_text: arrangement and use of unsymetrically gapped blades, with or without scrapers, in
such a manner as to facilitate continuous or intermittent emptying, driving, forcing
or squirting the material out of the container, or forward and backward through
nozzles, dies, spouts or feed or delivery rollers substantially as herein before
described and illustrated by the drawings.
1001
1005
GEO.
DOWNING,
8 Quality Court, London, W.C., Agent.