A NEW OR IMPROVED DOUGH MIXING OR KNEADING MACHINE
Year: 1881

page_text: LETTERS PATENT to Duncan Campbell MºKay, Baker and Adam Knox,
Engineer, both of the City of Glasgow, in the County of Lanark, North
Britain, for an Invention of "A NEW OR IMPROVED DOUGH MIXING OR
KNEADING MACHINE,"
PROVISIONAL SPECIFICATION left by the said Duncan Campbell McKay
and Adam Knox at the Office of the Commissioners of Patents on the
3rd May 1881.
DUNCAN CAMPBELL. MCKAY, Baker, and ADAM KNON, Engineer, both of the
City of Glasgow, in the County of Lanark, North Britain. "A NEW OR IMPROVED
DOUGH MIXING OR KNEADING MACHINE."
This Invention has reference to a new or improved combination of the parts or
construction of a machine, and in special parts thereof, for agitating, stirring,
mixing, or preparing and doughing the ingredients to be used in the manufacture
of bread, biscuits, and pastry baking or confectionery, and which has many
special novelties in its construction and action, giving important corresponding
advantages in the strength and portability, with little liability to derangement or
breakage of its parts, while being more generally useful, and doing the work
better and quicker, with less expenditure of power, than the best machines
heretofore in use for the said purpose.
or
This machine, like some others for the like purpose, has its main vessel, into
which the flour and water or other ingredients to be mixed and treated are put,
made of a long, horizontal, parallel Ushaped trough in cross section, with close
semi-cylindrical bottom preferably formed of sheet-iron or steel and open at the
top, and some distance down on the front side fitted with hinged or other folding
portable doors for the filling in of the materials, and their removal when treated.
This vessel is formed with close vertical ends, preferably of strong cast-iron with
a smooth surface on the inside, the malleable iron or steel body being secured by
countersunk headed rivets or bolts, and strengthened by angle irons at the upper
open edges with bands round the outside of the jointed parts, the whole being
carried on strong hollow eyes or trunnions formed on the ends, which may be

page_text: turned on the outside as journals to revolve in plummer blocks or other bearings
in strong end standards or frames close to the vessel, or on to the shafts passing
through them, which like other similar outer end frames carrying all the bush
bearings of the shafts and gearing of the machine are secured by broad basement
flanges to a strong deep box or vertical flanged bed-plate or frame, all so as to
carry the whole machine and its working mechanism and gearing in a portable
and self-contained manner, ready for being secured to any convenient founda-
tion of stone or brick-work, or to the beams and floors of baking houses.
An important new feature or improvement in this Invention and machine con-
sists in the use of two mixing frames, each with adjusting, cutting, or screwing
blades, the one frame revolving on a central solid spindle working concentrically
within the other on a hollow spindle, and having their. blades projecting radially
towards each other. The radial blades of the centre frame project outwards from
its longitudinal bars (preferably two bars to each set secured on opposite sides of
their axes) towards the blades of the two outer longitudinal bars or frames, and
in the spaces between them which project radially inwards. Thus the one set of
blades revolve in the spaces between the others, either in reverse directions or in
the same direction, as will hereinafter be described, so as to thoroughly mix the
Hour and water, or liquids, yeasts, ferments, or salts to a uniform consistency or
dough. The ends of the hollow spindles have each a long thin transverse cross-
head or bar formed on them for securing the ends or flanges of the two longitu-
dinal bars of the outer blades, and the inner ends of the central solid spindles
or shafts working within the former have shorter but similar crossheads for
securing the longitudinal bars of the inner revolving frame with its blades. In
the long or largest sized machines the central and hollow shafts or spindles of
these revolving blade frames are driven by duplicate gearing at both ends of the
machines the shorter and smaller machines are only driven by gearing at the
one end, all as follows:-The hollow spindles are shorter than the central solid
spindles on which they work out through the deep eye or trunnion on each end of
the mixing case, so as to revolve in the bush bearings of the inner end franies,
and projects so far beyond this as to have its large driving spur wheel secured on
it, and actuated direct by a small pinion at one or both ends of the machine,
keyed on the long main first motion driving shaft, carried past the back of the
mixing vessel in bush bearing blocks in the upper end frames. Each central solid
spindle works out through its outer hollow spindle as a bearing, and beyond its
driving wheel, to work in a bearing pillow block at its outer end in the second
outer end frames, and have its driving spur wheel mounted on it close inside the
frames, preferably loose, and a little smaller in diameter than the wheels of the
hollow shafts, so as to be driven in the opposite direction to these from corre-
sponding pinions on the first motion shaft, actuating a rather larger pinion on a
counter or intermediate shaft, carried below the first motion shaft in journal bear-
ings in the two end frames by this latter pinion gearing into the said spur wheel
at one or both ends of the machine. The main first motion shaft is by another
improvement driven at, two different speeds (at one or both ends) by a large or
small pair of fast and loose pulleys, the smaller pair preferably mounted between
the pinions driving the large spur wheels of the central and hollow shafts, and
the large ones outside the two end bearing block frames, but with an outer third
bearing frame carrying the outer end journal of the first motion shaft beyond
the large belt pulleys. The large slow speed pulleys are for driving the mixing
blade frames slowly and powerfully when mixing the tougher consistency of
dough, and the smaller high-speed pulleys for mixing the softer or lighter kinds
of dough, or the liquid and flour, or other mixtures of water, barm, yeast, or
ferment for leavening, and for mixing and setting up the batches with the dough.
ready for shaping and baking or cooking. The inner or adjacent faces or ends of
the eyes of the large spur wheels are formed with locking clutches, preferably
with four-prongs and catches, and having a corresponding double faced sliding
or reversing clutch box mounted by a feather and groove on the central solid shaft

page_text: between the clutches of the spur wheels to take into that of its own, and so drive
the inner blade frame in the opposite direction to that of the outer blade frame,
which works upwards on the front side with the advance edges of its longitudinal
bars angled, and close to the inner lower surface of the vessel and remove the
material therefrom, and thoroughly mix it with the central portion thrown out-
wards towards it by the central frame, all so that the material is fully mixed in
a few minutes between the blades of both frames running in reverse directions,
while their blades are angled in the same direction, so that the one set screws the
material towards the one end of the trough, while the other set screws the material
in the reverse direction towards the other end, all between the blades, which has
a most perfect intermixing and kneading effect in making a homogeneous pulp,
mixture, or dough. Then when a less cross or double kneading effect is desired,
and a more rotative agitating or churning effect is required, as for mixing fer-
ments and sponging, the central frame of blades can be stopped by shifting the
hand lever. of the clutch box, and taking it out of gear with its spur wheel, and
secured in this position by a swivelling catch for the purpose.
The largest
machines may thus be worked with much less power, or, when desired, at a
greater speed, by the smaller driving pulleys, or by one set of the belts and pulleys
at one end of the machine. And when dough is being treated and a rolling and
dividing of it into two or four sections or parts is desired, as for delivering it for
making up into bread or biscuits, then the clutch box on the central shaft may
be shifted into that on the spur wheel on the end of the hollow spindle of the
outer blade frame, either in the same plane therewith for making two roll divisions
of the dough, or be engaged cross-wise at right angles to each other so as to
separate the dough into four roll divisions. The mixing trough or vessel is
fitted at one end with a usual arrangement of screw wheel, and a screw working
into it on a hand crank spindle carried in journal bearing brackets secured
to one of the end frames'; but by the shaking of the vessel this screw wheel
arrangement has been found to shift, and is insufficient to hold the trough
steady, which defect has been cured by the improvement or application of a small
frictional brake pulley on the screw spindle, with a split clastic friction strap or
gland tightened up at the joint by a screw bolt passed through the ends or flanges
of the strap to a stop flange on one of the bearing brackets close to the friction
pulley. A long recess or gap is formed in the front part of the bed plate or frame
of the machine below the whole length of the mixing trough or vessel for allow-
ing an ordinary shallow and low wheeled box carriage being traversed in under
the mixing vessel, which is swivelled round on its end gudgeons or eyes, by its
screw wheel spindle to discharge the dough or other mixture into the receiving
carriage box for removal on its wheels. Shifting belt forks and hand levers are
fitted on centres in the framing at each pair of the fast and loose driving pulleys,
and also a shifting hand lever and retaining catch to the revolving clutch box:
and when this driving gearing is fitted at both ends of the machine, these hand
levers are connected by long rods and connecting levers so as to be actuated
simultaneously by a person at either lever and end of the machine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said by Duncan Campbell McKay and Adam Knox in the Great Seal
Patent Office on the 2nd November 1881.
DUNCAN CAMPBELL MCKAY, Baker, and ADAM KNOX, Engineer, both of the
City of Glasgow, in the County of Lanark, North Britain. A NEW OR IMPROVED
DOUGH MIXING OR KNEADING MACHINE."
Our said invention has reference to a new or improved construction or combi-
nation of the parts of a machine for agitating, stirring, mixing, or kneading and
doughing the ingredients to be used in the manufacture of bread, biscuits, and
pastry baking or confectionery, and which has many special features of novelty
in its construction and action, giving corresponding advantages as regards strength
and portability, with little liability to derangement or breakage of its parts.
And in order that our said Invention and the manner of performing the same
may be properly understood, we have hereunto appended for that purpose a Sheet
of explanatory Drawings to be hereinafter referred to, and representing modifi-
cations of our improved dough mixing or kneading machine. In these Draw-
ings the same reference letters are used to mark the same or like parts where
repeated in the several Figures.
Figure 1 of the Drawings is a front elevation, partly in section, of the
improved machine; Figure 2 is a plan, and Figure 3 is an end elevation of the
same while Figure 4 is a transverse vertical section taken as at. the line 1--1
in Figure 1 Figures 5 and 6 are a transverse vertical section and part plan of
another modification of the machine.
Referring to these Drawings, the improved machine is constructed with a long
horizontal parallel trough of shape in cross section, with close semi-cylindrical
bottom A, preferably formed of sheet-iron or steel, into which the flour and water
and other ingredients to be mixed and treated aro put.. This trough A is made
open at the top and some distance down on the front side, where hinged or other
folding or portable doors B, B', are fitted for convenience of filling in the dough
materials, and for their removal when treated. This vessel A is formed with close
vertical ends A, preferably of strong cast-iron, with a smooth surface on the
inside, the malleable iron or steel body A being secured by countersunk headed
rivets or bolts, and strengthened by angle irons a at the upper open edges, with
bands round the outside of the jointed parts. The trough or vessel A is carried
on strong hollow eyes or trunnions A2 formed on the ends, which are turned on
the outside at a² as journals to revolve in plummer blocks or other bearings c in
strong end standards or frames C, C, close to the vessel. These outer end
frames C, C, carry all the bush bearings of the shafts and gearing of the machine,
and are secured by broad basement flanges C³ to strong deep boxes or vertical
flanged bed-plates or frames C2 at each end, so as to carry the whole machine
and its working mechanism and gearing in a portable and self-contained manner
ready for being secured to any convenient foundation of stone or brickwork,
or to the beams and floors of baking houses.
An important new feature or improvement of this machine consists in the use
of two mixing frames D and E, each with cutting or screwing blades d, c. The
one frame D revolves on a central solid spindle D working concentrically within
the other on a hollow spindle E at each end of the machine, and the blades d, e,
of these mixing frames D, E, project radially towards each other. The radial
blades of the centre frame D project outwards from the longitudinal bars D, D,
(there being preferably two bars to each set secured on opposite sides of their
common axis), and the blades e of the two outer longitudinal bars or frames E, F,
project radially inwards, towards, and into the spaces between these inner
blades thus the one set of the blades dor e may be made to revolve in the

page_text: spaces between the others, e or d, either in reverse directions or in the same
direction by means of gearing hereinafter described, so as to thoroughly mix
the flour and water, or liquids, yeasts, or ferments and salts to a uniform con-
sistency or dough. The inner ends of the hollow spindles E¹, E', have each a
long thin transverse crosshead or bar E formed on them for securing the ends
or flanges of the two longitudinal bars E, E, of the outer blades e, and the inner
ends of the central solid spindles or shafts D', D, working within the hollow
spindles E, E, have shorter but similar crossheads D, De, for securing the
longitudinal bars 1), D, of the inner revolving frame with its blades d.
In the long or largest sized machines the central and hollow shafts or spindles
D, E, of these revolving blade frames D, E, are driven by duplicate gearing at
both ends of the machine; the shorter and smaller machines are only driven by
gearing at the one end. The hollow spindles are shorter than the central solid
spindles on which they work; and through the deep eye or trunnion A2 on
each end of the mixing case or trough A, and they revolve in the trunnions A²
as bearings. Each hollow spindle E' projects so far beyond its bearing as to
have its large driving spur wheel F secured on it, and be actuated direct by a
small pinion F at one or both ends of the machine, keyed on the long main first
motion driving shaft F2, which is carried past the back of the mixing vessel A
in bush bearing blocks in the upper part of the end frames C, the shaft F2
extending out at both ends, and being supported in bearings f, f, in outer carry-
ing brackets C3, C4. Each central solid spindle 1) works out through its outer
hollow spindle E as a bearing and beyond its driving wheel, to work in a bearing
pillow block ct at its outer end in the second outer end frames C, and the driv-
ing spur wheel G of each shaft. 1) is mounted on it close inside the frames (³,
and is fitted loose (and made preferably a little smaller in diameter than the
wheels F of the hollow shafts), so as to be driven in the opposite direction to
these from corresponding pinions G on the first motion shaft F2, actuating a
rather larger pinion G2 on a counter or intermediate shaft carried below the
first motion shaft in journal bearings in the two end frames C, C³, this latter
pinion gearing into the said spur wheel G at one or both ends of the machine.
The main first motion shaft F is by another improvement driven at either of
two different speeds (at one or both ends) by a large or small pair of fast and
loose pulleys H, H', or h, h', the smaller pair h, h, preferably mounted at one
side only, as shown in Figures 1 and 2, between the pinions F1, G', driving the
large spur wheels F, G, of the central and hollow shafts D, E, and the large
ones HH, outside the two end bearing block frames C, C3, but with an outer
third bearing block frame C+, carrying the outer end journal of the first motion
shaft F2 beyond the large belt pulleys H, H. The large slow speed pulleys H, H',
are for driving the mixing blade frames slowly and powerfully when mixing the
tougher consistency of dough, and the smaller high speed pulleys h, h, for
"sponging" or mixing the softer or lighter kinds of dough, or the liquid and
flour or other mixtures of water, barm, yeast, or ferment for leavening and for
mixing and setting up the batches with the dough ready for shaping and baking
or cooking. The inner or adjacent faces or ends of the bosses or eyes of the
large spur wheels F, G, are formed with locking clutches I, I, preferably with
four prongs or catches, and having a corresponding double faced sliding and
reversing clutch box 12 mounted by a feather and groove on the central solid
shaft D between the clutches I, 1, of each pair of spur wheels F, G, and these
clutch boxes I may be shifted by a hand lever J at either end to take into the
clutch I on the spur wheel G (which is loose on the shaft D), and so drive the
inner blade frame D in the opposite direction to that of the outer blade frame E,
which works upwards on the front side, with the advance edges of its longi-
tudinal bars e angled and close to the inner lower surface of the vessel A.
action of the blades e removes the material from the surface of the vessel A, and
thoroughly mixes it with the central portion thrown outwards towards it by the
central frame 1. The material is thus fully mixed in the space of a few minutes
This

page_text: between the blades d, e, of both frames D, E, running in reverse directions, while
their blades d, e, are angled in the same direction, so that the one set. tends to
screw the material towards the one end of the trough, while the other set tends
to screw the material in the reverse direction towards the other end between the
blades, the result being a most perfect intermixing and kneading effect in making
a homogeneous mixture or dough. When a less cross or double kneading effect
is desired, and a more rotative agitating or churning action is wanted, as for
mixing ferments and sponging," the central frame 1) of the blades can be
stopped by shifting the hand lever J of the clutch box 12, and taking it out of
gear with its spur wheel G, the hand lever being secured in this position by a
swivelling catch for the purpose. The largest machines may thus be worked with
much less power, or when desired at a greater speed by the smaller driving
pulleys, or by one set of the belts and pulleys H, H¹, at one end of the
machine.
When dough is being treated and a rolling and dividing of it into two or four
sections or parts is desired, as for delivering it for making up into bread or his-
cuits, then the clutch boxes 12, 12, on the central shaft D' may be shifted into the
clutches I, I, on the spur wheels F, F, on the ends of the hollow spindles E, E',
of the outer blade franie E, either when in the same plane with the inner
frama D, as indicated in Figure 2, for making two roll divisions of the dough,
<r to be engaged cross-wise at right angles to each other, as indicated in Figure 4,
so as to separate the dough into four roll divisions.
The mixing trough or vessel A is fitted at one end with an ordinary arrange-
ment of screw wheel K, and a screw & working into it on a hand crank spindle,
carried in journal bearing brackets secured to one of. the end frames C. By
the shaking of the doughing vessel, screw wheel arrangements of this kind have
been found to shift, and are insufficient to hold the trough steady. This defect
has been remedied by the improvement or application of a small frictional brake
pulley on the screw spindle k', with a split elastic friction strap or gland
tightened up at the joint by a screw bolt passed through the ends or flanges of
the strap, and fixed to a stop flange on one of the bearing brackets C close to
the friction pulley. The front covering door B of the vessel A can be removed
by the withdrawal of a retaining pin b. and the top cover 3 may be hinged back
on its hinges to hang over the back of the vessel A which is canted, as indi-
cated in dotted lines in Figure 4.
A long recess or gap is formed in the front part of the bed-plate or frame (2
of the machine below the whole length of the mixing trough or vessel A
for allowing an ordinary shallow and low wheeled box carriage L to be traversed
in under the mixing vessel A, which is swivelled round on its end gudgeons or
eyes A2 by its screw wheel K and spindle k, k, to discharge the dough or other
mixture in the receiving carriage box L for removal on its wheels 7. Shifting
belt forks M and hand fevers are fitted on centre brackets me fixed on to the
framing at each pair of the fast and loose driving pulleys H, H', and also a
shifting hand lever for the revolving clutch box 12. When this driving gear-
ing is fitted at both ends of the machine, as shown, these pairs of hand levers J
and are connected by long rods J2, M2, so as to be actuated by a person at
either lever J or M³, and corresponding end of the machine, a connecting lever J
being provided for the rods J to enable both cluich boxes 12, 12, to be moved
inwards or outwards simultaneously.
In constructing machines of the smaller class, the driving gear need not be
duplicated, but may be fitted at one end only, and arranged much the same as
for the larger class. Other arrangement of driving gear may however be used
both for the large and small classes of machines, a simple arrangement for the
latter being to fit a bevil wheel on each mixing frame spindle 1), E', in gear
with a bevil pinion fitted intermediately to drive the spindles D, E, in opposite
directions. One of the bevil wheels might be fitted loose on its spindle, and a
-clutch arrangement-similar_to_that..shown and described may be provided.

page_text: When the driving gearing is fitted at one end only of the machine, means
may be provided at the opposite end whereby the thrust on either of the mixing
frame spindles (which is in opposite directions in each owing to the screw action
of the cutting blades) may be taken up by the other, as by fitting an adjustable
screw cap on the end of one spindle to bear on the end of the other.
In the modification of the improved machine shown in Figures 5 and 6, the
inner blade frames are made in the form of separate revolving spindles D*, D*,
carried in bearings in the cross-heads or bars 2, which connect the outer blade
frames E, E, to their actuating hollow shaft E. At one or both ends of each of
these spindles D is fitted a spur wheel or pinion P, P, in gear with a pinion Q
fixed on the central solid shaft D. The central shaft is either kept stationary
or made to revolve in the opposite direction to the hollow shaft E carrying the
outer blade frames E. and through the pinion Q the pinions P, P, and spindles D*
are driven and caused to rotate with the blades d, cutting not only the dough
between the blades e on the other frame E, but also that which may remain in
the central space between the spindles or bars D*, D, the object of this arrange-
ment being to prevent the formation of a layer of unmixed dough in the space
between the bars of the inner blade frame. A clutch arrangement may be pro-
vided whereby the central solid shaft 1) may be made to revolve with the hollow
shaft to cause the inner and outer blade frames 1* and E¹ to be turned in one
direction, as for emptying the trough or vessel A, the coupling of the shafts
being effected when the blades are all lying in one plane, as shown in Figure 6,
or in planes at right angles.
Having thus described the nature of our said Invention, and the manner of
performing the same, we have to state that we do not confine ourselves to the
precise details herein described or delineated, but what we consider novel and
original and therefore claim as the Invention secured to us by the herein before
in part recited Letters Patent is,-
First. The general arrangement and construction or combination of the parts
of a machine for mixing, cutting; and kneading dough, in which two mixing
frames (D, E,) are fitted on spindles driven by gearing to revolve the one within
the other in the same or opposite directions, or mix and cut the dough material
within a containing trough or vessel, all substantially as herein described in
reference to and as shown in the accompanying Drawings.
Second. The construction and arrangement in doughing machines of two or
more mixing, cutting, and kneading frames provided with stirring blades, and
fitted on central spindles, these frames being arranged to revolve the one within
the other in the same or opposite directions to mix, cut, and knead the dough
materials within the containing vessel, all substantially as herein described in
reference to the accompanying Drawings.
In witness whereof, I, the said Adam Knox, have, on behalf of the said
Duncan Campbell McKay and myself, hereunto set my hand and seal,
this First day of November, in the year of our Lord Que thousand eight
hundred and eighty one
Witness,
WALLACE FAIRWEATHER, C.E.,
Of W. R. M. Thomson & Co.,
Patent Agents,
Glasgow.
ADAM KNOX. (L.S.)