IMPROVEMENTS IN AND APPLICABLE TO KNEADING AND MIXING MACHINES, AND IN THE MODE OF DRIVING AND REVERSING SUCH MACHINES
Year: 1878

page_text: "
LETTERS PATENT to Paul Pfleiderer, of Norwood, in the County of Surrey,
Engineer, for the Invention of IMPROVEMENTS IN AND APPLICABLE TO
KNEADING AND MIXING MACHINES, AND IN THE MODE OF DRIVING AND
REVERSING SUCH MACHINES."
PROVISIONAL SPECIFICATION left by the said Paul Pfleiderer at the Office
of the Commissioners of Patents on the 31st December 1878.
PAUL PFLEIDERER, of Norwood, in the County of Surrey, Engineer. " IMPROVE
MENTS IN AND APPLICABLE TO KNEADING AND MIXING MACHINES, AND IN THE
MODE OF DRIVING AND REVERSING SUCH MACHINES."
My Invention relates to improvements on the Inventions described in the Speci-
fications of the Patents granted to me, and bearing date respectively 26th November
1875 (No. 4116), and 20th July 1876 (No. 2953).
And my Invention consists in the first place in so forming the blades or mixers
used in kneading and mixing machines as to dispense with the central bosses for
securing the blades on their shafts, and in transmitting motion to them through
radial arms, which serve also as fixed scrapers similar to those described in the
Specification of my former Patent, No. 4116 (1875), such arms reaching over or
beyond the central line of the axis of the blade, and being adapted in form and
strength to suit the required purpose to which they are or may be applied.
In some cases also, instead of perforating the blades, a large portion thereof may
be taken out on one side of the axis, or two portions on opposite sides of the same,
thereby increasing the clearance for the passage of the material under operation
without diminishing the efficient action of the blades or mixers.
My Invention consists in the second place in combining two or more of such
blades or mixers revolving at different speeds, with a trough bottom composed of a
corresponding number of suitably formed concave portions, having a bridge or

page_text: bridges between them, as described in the Specifications above referred to, thereby
forming or constituting a kneading or mixing machine similar to those described
therein. The said blades or mixers may be driven at different speeds as required
by suitable differential toothed gear or otherwise.
My Invention consists in the third place in adapting and applying to either of
the machines above referred to any suitable apparatus for impregnating with
carbonic acid, air, or other suitable gases the substances or material under operation
in such machines, or for conveniently pressing such substances or material out of the
machine when finished, or for both of such purposes. In such cases the trough,
instead of being open, is constructed as an air-tight vessel, fitted with suitable
receptacles for the entrance of gas and water, and a man hole for putting in the dry
ingredients, and also with suitable cocks or outlets for withdrawing the finished
material.
My Invention consists in the fourth place in arranging any required number of
blades or mixers round a common central axis, on which the trough in all its several
portions is mounted, and made to revolve.
The trough in this case is composed of two ends and a series of trough bottoms
and bridges, forming a kind of drum on the central axis. For the admission and
discharge of the material the trough is provided with one or more openings, which
can be closed as required by means of slides, or valves, or otherwise.
And my Invention consists in the last place in constructing the machine so as to
admit of the trough being readily either tilted or lowered away from the driving
gear or from the blades or mixers, as may be required, for emptying or cleaning
without the necessity of having the axis of the driving shaft of the machine
coinciding with the axis of the trunnions on which the trough can be turned.
For these purposes either the whole trough or only the trough bottom in con-
nection with the ends of the trough (but separate from the sides between which in
this case it is made to fit closely) is constructed so as to be capable of being turned
on trunnions, the axis of which coincides with that of one of the blades or mixers;
or the trough may be taken away entirely, in which case it is sometimes useful to
construct the blades so as to be removable from the trough, or the sides and the
blades may be fixtures, and the trough bottom with the ends may be lowered away
from them, thereby leaving both the trough and the mixers free as required, and
facilitating the arrangement of the driving gear.
By adapting and applying to the machines above referred to, or to kneading and
mixing machines of other constructions, the improved apparatus for transmitting
and reversing motion described in the Specification of the Patent granted to me,
and bearing date 27th September 1877, No. 3623, such machines will be improved
both in expedition and efficiency of operation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Paul Pfleiderer in the Great Seal Patent Office on the 30th June
1879.
PAUL PFLEIDERER, of Norwood, in the County of Surrey, Engineer. "IMPROVE-
MENTS IN AND APPLICABLE TO KNEADING AND MIXING MACHINES, AND IN THE
MODE OF DRIVING AND REVERSING SUCH MACHINES."
My Invention of "Improvements in and Applicable to Kneading and Mixing
Machines, and in the Mode of Driving and Reversing such Machines" relates to
improvements on the Inventions described in the Specifications of the Patents
granted to me, and bearing date respectively Twenty sixth November, One thousand
eight hundred and seventy five (No. 4116), and Twentieth July, One thousand eight
hundred and seventy six (No. 2953).
And my Invention consists in the first place in so forming the blades or mixers
used in kneading and mixing machines as to dispense with the central bosses for
securing the blades on their shafts, and in transmitting motion to them through
radial arms, which serve also as fixed scrapers similar to those described in the
Specification of my former Patent, No. 4116 (1875), such arms reaching over or
beyond the central line of the axis of the blade, and being adapted in form and
strength to suit the required purpose to which they are or may be applied.
The clearance for the passage of the material under operation may also be
increased as required by taking out a large portion of the blade ou one side of the
axis, or two portions on opposite sides of the same, either while retaining the central
bosses of the blades or dispensing with them as above stated. In some cases also
the blades may be perforated.
My Invention consists in the second place in combining two or more of such
blades or mixers revolving at different speeds, with a trough bottom composed of a
corresponding number of suitably formed concave portions having a bridge or
bridges between them, as described in the Specifications above referred to, thereby
forming or constituting a kneading or mixing machine similar to those described
therein. The said blades or mixers may be driven at different speeds as required
by suitable differential toothed gear or otherwise.
My Invention consists in the third place in adapting and applying to either of
the machines above referred to any suitable apparatus for impregnating with
carbonic acid, air, or other suitable gases the substances or material under operation
in such machines, or for conveniently pressing such substances or material out of
the machine when finished, or for both of such purposes. In such cases the trough,
instead of being open, is constructed as an air tight vessel, fitted with suitable
appliances for the entrance of gas and water, and a manhole for putting in the dry
ingredients, and also with suitable cocks or outlets for withdrawing the finished
material.
My Invention consists in the fourth place in arranging any required number of
blades or mixers round a common central axis, on which the trough in all its several
portions is mounted and made to revolve. The trough in this case is composed of
two ends and a series of trough bottoms and bridges, forming a kind of drum on
the central axis. For the admission and discharge of the material the trough is
provided with one or more openings, which can be closed as required by means of
slides or valves or otherwise.
And my Invertion consists in the last place in constructing the machine so as
to admit of the trough being readily either tilted or lowered away from the driving
gear, or from the blades or mixers, as may be required for emptying or cleaning,
without the necessity of having the axis of the driving shaft of the machine
coinciding with the axis of the trunnions on which the trough can be turned.
For these purposes either the whole trough or only the trough bottom in con-
nection with the ends of the trough (but separate from the sides, between which in

page_text: this case it is made to fit closely) is constructed so as to be capable of being turned
on trunnions, the axis of which coincides with that of one of the blades or mixers;
or the trough may be taken away entirely, in which case it is sometimes useful
to construct the blades so as to be removable from the trough; or the sides and the
blades may be fixtures, and the trough bottom with the ends may be lowered away
from them, thereby leaving both the trough and the mixers free as required, and
facilitating the arrangement of the driving gear.
By adapting and applying to the machines above referred to, or to kneading and
mixing machines of other constructions, the improved apparatus for transmitting
and reversing motion described in the Specification of the Patent granted to me,
and bearing date Twenty seventh September, One thousand eight hundred and
seventy seven, No. 3623, such machines will be improved both in expedition and
efficiency of operation.
Having thus stated the nature of the said Invention I will proceed to describe
more particularly in what manner the same is to be performed by the aid of the
accompanying Drawings, in which are represented different forms of blades and
arrangements for mounting and working the same.
DESCRIPTION OF THE DRAWINGS.
In Sheet I., Figures 1 to 9 represent types of some of the new mixing blades or
arms.
The theoretical fundamental shape of the blade or its mathematical centre-surface
is the surface obtained by intersecting the body which is enclosed by the surface of
revolution representing the path described by the blade as it revolves. The portions a
interrupt the continuity of the blades, but leave so much of its periphery as is
necessary to give a full sweep of the blade in the trough bottom.
The size of the gaps a, as well as the inclination and curvature of the blades,
varies according to the nature of the material to be operated upon, as well as with
the amount of driving power obtainable, as the case may be.
Figures 10 and 11 shew a very simple arrangement of a small machine with two
blades of the type, Fig. 5, in the open trough, the top part of which is represented
by Figure 11.
The foregoing Figures illustrate some typical forms of my Invention in its simplest
or elementary character.
In Sheet II., Figures 1 and 2 shew a vertical section and a side elevation of my
new machine as it is designed to facilitate the discharge of the material by con-
veniently tilting it and taking it to pieces. The pulley R, which is fixed to the
pinion T, can be brought to correspond with the pulley by sliding it outwards on
the axle a, so that a belt can be laid on for obtaining a higher speed.
"
Figures 3 and 4 shew the trough of this machine with the blades removed.
The hinged bearings of the standard answer the double purpose of forming con-
venient fulcrums for tilting the trough, and of holding together the two halves of
the trough.
In Sheet III., Figures 1 and 2 shew in side and end elevation an arrangement in
which the trough may either be cast in one or in halves, or it may be lined with a
lining of any suitable metal. The trough may be tilted down while the machine is
in motion in order to facilitate the discharge of the material.
The driving gear is enclosed in the hollow standard, from which the driving
shaft a projects on both sides.
By means of the lever h the speed of the machine may readily be altered.
The excentric levers k, by assuming their natural position in hanging down, hold
the trough in position when up, while in order to lower the trough they have to be
lifted up, when the person so lifting them has to support half the weight of the
lowering trough.
An additional variety of speeds can be produced if the shaft b is made capable of
having power applied to it.

page_text: In Sheet IV., Figures 1 and 2 shew the simple machine, one end and part of the
bottom of which are constructed as a door, which can be lowered away from the
blades, this being the most convenient mode of emptying the machine of some kinds
of material while working.
Its having that half of the trough which is nearest to the outlet formed by the
said lowered away door considerably lower than the other half is also of great
importance for convenient discharge of the finished material.
For fastening the said door I use an arrangement which is shown in plan at
Fig. 2, Sheet V, as fitted to the door of the machine represented in such Sheet.
The machine can have two speeds, that is to say, either through the pinion A
being made to gear in the wheel B for slow speed, or in the wheel D for fast speed,
at will.
My reversing gear is mounted on the driving shaft a.
The blades, as shewn, are driven by and coupled with the driving wheels by
means of bushes with square holes, in which the steel shafts & fit. These shafts can
be withdrawn, and the blades disconnected without interfering with the driving gear.
For this purpose either blades, constructed as shewn in Figs. 3 and 7, Sheet I.,
with or without central bosses, are used, and the square shafts carried straight
through, or the blades are constructed after the type shewn at Fig. 7, Sheet I., and
connected with their shafts, as shewn in Fig. 2, by means of a ring win two halves
fitting into a groove formed in the end of the shaft, and held together by means of
a full ring o fitting over the two halves of w.
In Sheet V., Figures 1 and 2 shew in vertical section and plan a similar machine
to the one shown on Sheet IV., with the exception that in this machine a pair of
driving wheels are used for every blade, one on each side of it, so as to meet the
great resistance offered to the blades by very hard or tough masses of material
under operation.
This arrangement of two driving wheels 8-8 and t-t for each mixing shaft is of
special importance in machines with two or more blades on each mixing shaft, that is
to say, in duplex or multiplex machines, and it has the further advantage that the
shafts may be kept of less thickness so as to make them act as a sort of torsional
springs, whereby the distribution of the necessary power on the two wheels is
directly regulated.
The blade shewn in Fig. 1 has a nearly elliptical shape, while that represented
in the plan is of a more complicated curvature.
The driving gear of this machine is arranged as follows:-On the driving shaft a
there is a hollow shaft c, which is free to revolve but can be made fast; x, x¹, and y,
are wheels fixed on the shaft c; v is a fixture on a, but laterally moveable.
The
wheels and z are fixtures, the shaft b, but also laterally moveable. By
means of a lever arrangement can be thrown in and out of gear with y, and u
with v, so that when a gears with y, v gears with u, thereby causing the machine to
work at slow speed, while when z is out of gear with y, v is coupled with x by means
of corresponding clutches cast on these two wheels. In this case the shafts a and c
revolve as one, and the machine works at its fast speed.
In Sheet VI., Figures 1 and 2 shew an end view and a longitudinal section of one
of the simplest forms of my new blades with central bosses and square through
shafts & in combination with loose scrapers E.
Two similar blades with movable scrapers are drawn in Fig. 3 as mounted on
one common shaft in one half of the trough, while in the other half of the trough
two blades are shewn, as being driven independently of each other.
Figures 4 and 5 are further examples of characteristic shapes of blades.
Fig. 6 shews a pair of blades of the new type fitted in a revolving pan after the
so called edge runner or Mélangeur type.
Fig. 10 shews the form of blade fitting the trough represented in Figures 7, 8,
and 9 after the gaps are cut out.
Figures 11 and 12 are diagrams representing other arrangements of a fixed frame-
work and driving gear, with part of the walls forming the trough removable in such

page_text: a manner as admits of easy access to the blades and the interior of the trough for
cleaning as well as discharging purposes. In all the said arrangements it is not
necessary that the axis of the driving shaft should coincide with that of the tilting
trunnions. Figures 13, 14, and 15 illustrate a blade with moveable scrapers Ĕ
scraping the flat surfaces of their respective blades in which the gaps are
formed.
In Sheet VII., Figures 1 and 2 show a simple machine for working under
pressure or vacuum, and out of which the finished material can be drawn through
a sort of taps.
By means of communicating tubes between both taps the material may be drawn
out through one opening only, or the trough may be tilted for that purpose, thereby
dispensing with an opening in one of the halves of the trough bottom. On the
flange at the top is fitted a cover mounted with the necessary fittings, sockets, and
manholes for connecting the trough with pumps or other apparatus, as well as for
charging it with the raw materials. This or a similar renders my machine very
valuable for the manufacture of aërated bread, of soda water, and similar
manufactures.
Fig. 3 shews a sectional plan of a machine with hinged doors forming one side of
the trough, and carrying the bearings for one end of the shafts. By partly with-
drawing these shafts through the bearings in the doors, and disengaging their
couplings with the shafts of the wheels, the blades are made free and can, while
hanging at the doors, be withdrawn from the trough by simply opening the doors
and turning the projecting shafts as required.
This manipulation is made easy by having the gaps a in the blades, while blades
with an entire periphery are rather difficult to get out with the doors.
Figures 4 and 5 shew a simple arrangement of two of my blades in a trough
with only one axis, while in Fig. 5 the dotted lines indicate one with three axes.
Fig. 6 shows a cross section through a machine with four blade axes, the walls of
the trough of which are continuous, and form a sort of drum, which can revolve on
an excentric shaft. The drum is driven by a toothed wheel or a strap pulley. The
wheels on the blade shafts gear either into a pinion or into a wheel with internal
teeth, the axis of either of which lies in the prolongation of that of the trunnions of
the drum. This pinion or wheel is fixed to the framework on which the bearings
for these trunnions are mounted, so that by turning the drum the blade shafts are
forced to revolve also.
A slide or valve serves as a manhole for the entrance and exit of the material.
Figures 7 and 8 shew an arrangement of my machine for either continuous or
intermittent action, in which the advancement of the material in a direction parallel
to the axis of the machine is caused by spirals or archimedian screws inserted
between the mixing blades on their shafts, for which purpose the gaps in the blades
are of special value.
In Sheet VIII., Figures 1 and 2 show a front and side elevation of another
arrangement of my machine, in which the trough may be readily tilted on trunnions,
the axis of which corresponds with that of one of the blade shafts, but not with the
driving shaft. This machine can also be worked while the trough is tilted for
discharging.
I prefer to make the hinder bosses rest in elastic bearings, which may be half
plummer blocks with elastic linings in order to avoid any injurious effects from a
shock caused by dropping the trough back into its working position, in which
position it is held by a lever L fitting over a pin on the stationary framework. This
lever is connected to the trough by a bolt, on which it is movable in such a manner
that when disengaged from the pin on the frame it can be lifted until it is in a
nearly horizontal position, so as to give great leverage for lifting the trough when
this is heaviest, while it forms a suitable handle to prevent the trough from incon-
veniently tipping over its dead point.
For altering the speed of the machine the pinion on the driving shaft can be
shifted laterally so as to gear in either of two driving wheels in the same manner

page_text: as pinion A, Sheet IV.; it is so shifted by means of a circular rack fixed to it and
a small pinion which is keyed on a shaft worked by a handle H.
The different illustrations of my Invention hereinbefore described represent
separate blades or machines as embodying each some distinct feature of construction,
in order to shew more clearly in what manner, notwithstanding such distinctions
of form, they are only modifications of one and the same principle, designed to
answer one and the same general purpose of a perfect mixing and kneading machine
or apparatus.
Having thus described the nature of the said Invention, and in what manner the
same is to be performed, I would have it understood that I do not claim as of my
Invention any of the parts of machinery or modes of construction heroinbefore
described, otherwise than as adapted and applied to machines of the kind or kinds
described in the Specifications of my Patents, No. 4116 (1875), and No. 2953
(1876), that is to say, machines in which two or more revolving blades or mixers
revolving at different speeds are combined with a trough or troughs having suitably
formed concave walls or bottoms with a bridge or bridges between them; but what
I do claim as of my Invention is,-
First. The adaptation and application to such machines of one or more of the.
improvements and modifications of construction herein before described and referred
to, so far as they are not contained in either of my said former Patents.
And, Secondly. The elliptical or ellipsis-like blade or blades represented in Figures
1 to 8 (Sheet I.), with gaps a formed therein, and hereinbefore described under the
first head of my Invention.
In witness whereof, I, the said Paul Pfleiderer, have hereunto set my hand
and seal, the Thirtieth day of June, in the year of our Lord One thousand
eight hundred and seventy ninc.
Witness,
WILLIAM SPENCE,
8, Quality Court,
Chancery Lane.
PAUL PFLEIDERER. (L.S.)