IMPROVEMENTS IN MACHINERY FOR MAKING BRICKS
Year: 1874

page_text: LETTERS PATENT to Christopher William Thairlwall, of Leeds, in the
County of York, for the Invention of "IMPROVEMENTS IN MACHINERY
FOR MAKING BRICKS."
Scaled the 16th April 1875, and dated the 21st October 1874.
PROVISIONAL SPECIFICATION left by the said Christopher William
Thairlwall at the Office of the Commissioners of Patents, with his
Petition, on the 21st October 1874.
I, CHRISTOPHER WILLIAM THAIRLWALL, of Leeds, in the County of
York, do hereby declare the nature of the said Invention for "IMPROVE■
MENTS IN MACHINERY FOR MAKING BRICKS," to be as follows:-
My Invention relates to brickmaking machines which have a hori-
zontal pug mill and revolving mould wheel. The pug mill shaft is
furnished with knives, and carries a strong cast-iron worm securely
keyed on its end to force the clay into the moulds in the said mould
wheel when they are opposite the aperture in the discharge box of the
pug mill, which box is somewhat less in size than the mould itself. The
said discharge box is also furnished with a surplus or overthrow pipe to

page_text: prevent, any undue strain on the pug mill shaft when the mould wheel
is turning. The said pug mill is placed on a frame, and is so arranged
that it can be kept in close contact with the mould wheel, and prevent
any escape of clay except into the moulds. The pressure given to the
clay by the worm of the pug mill will vary according to the length of
the discharge pipe.
The said mould wheel has four moulds extending inward from its
periphery, and provided with moving or sliding bottoms connected
internally by wrought-iron rods or bolts in such manner that the pressure
of clay from the pug mill when filling one mould discharges the brick
from the opposite mould, or the same result may be obtained by an
internal cam motion, if desirable or convenient.
Underneath the mould wheel, and perpendicular to the axis of the pug
mill, is a hollow plunger working in grooved bearings fixed in the frame
of the machine, and which is moved up and down by a cam upon a shaft
immediately under the mould wheel. The bearings of this shaft are
fitted to slide in the said frame, and are kept in position by two levers
which are provided with weights, and so arranged as to apply the
required pressure on each brick. This pressure may be varied by
adjusting the weight on the said levers to any variation in the nature
or quality of the clay, and to prevent the possibility of any accident to
the machine, as when the limit of pressure to which the machine is
regulated is reached the said lovers allow the shaft to yield. The
movement of the mould wheel is intermittent, and is effected by the
application on both sides of the wheel of a rocking bar, which operates a
pull catch, and which receives its motion from a crank pin on a large
toothed wheel.
The aforesaid plunger is provided with two holes for the exit of the air
and surplus clay whilst the brick is being pressed. To prevent the
adhesion of the clay to the said plunger the same is kept hot by passing
steam through it by means of flexible piping. It is also fitted with a
self-acting lubricating brush, to be used when steam cannot be con-
veniently applied, and which is supplied with oil from an oil cistern
above the mould wheel.
The said mould wheel makes a quarter revolution at each movement,
and is held during the pressing of each brick by a spring catch or
trigger. The mould wheel has four notches corresponding with the four

page_text: moulds, and the said catch or trigger is forced by its spring into each of
these notches as they come into the proper position. The said trigger
has a rod or bar provided with an antifriction roller, which works in
contact with a cam. Immediately before the action of the aforesaid
pull catch the said cam withdraws the trigger from the notch, and
releases the mould wheel, which thus makes another quarter revolution,
and so on.
The said machine has a short cross shaft driven by a belt and pulley,
and provided with a small pinion, which imparts the required motion to
the cam shaft wheel. It has also a bevel pinion working into a bevel'
wheel on a horizontal shaft, on the opposite end of which is a toothed
pinion giving motion to the large toothed wheel on the pug mill shaft.
This large wheel is loose on the said pug mill shaft, and transmits its
power through a brake strap and wheel. The said wheel is fast on the.
shaft, and the brake strap is passed around it, and attached to the said
toothed wheel. This strap will bind up on the wheel with sufficient
pressure to rotate the shaft under ordinary circumstances, but if any
large stone or the like should be thrown into the pug mill the brake
strap will slip and prevent breakage of the pug mill shaft, knives, or
other parts. The pug mill shaft is provided with collars which run in a
grooved bearing similar to the thrust bearing of a screw propeller, and
which resist the endwisc strain on the said shaft.
I may also modify this machine to adapt it as a brick press by dis-'
pensing with the pug mill and gearing connected with the same, and
cutting off the part of the frame behind the rocking bar, which gives the
intermittent motion to the mould wheel, and by operating a plunger from
the rocking bar shaft for feeding the green brick or clay into the mould;
or I may use it for making bricks of dry ground clay fed from a hopper
fixed on the frame of the machine above a plunger so arranged that the
clay falls in sufficient quantity to form a brick into a trough in which
the plunger works, and by which it is pushed forward into the mould,
and afterwards pressed into the form of a brick by the cam plunger, as
above described.
My improved machine is self-contained. The arrangement of gearing
is neat and compact; there is no possibility of breakage from over
pressure, and the pressure can be regulated to suit any material. Should
the apparatus which imparts the intermittent motion to the mould
Accidents to
wheel fail to act at any time no accident would result.

page_text: the pug mill are prevented by the use of the frictional apparatus or brake
for driving the pug mill shaft, and all wearing parts of the machine can
be renewed at a very slight cost. The bricks when made are as hard as
it is possible to make really good hard plastic or semi-dry bricks. In
appearance they will resemble ordinary hand pressed facing bricks with 5
a panel on both sides, providing the material be properly prepared.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Christopher William Thairlwall in the Great Seal
Patent Office on the 21st April 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHRISTOPHER
WILLIAM THAIRLWALL, of Leeds, in the County of York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of October, in the
year of our Lord One thousand eight hundred and seventy-four, in
the thirty-eighth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Christopher William
Thairlwall, Her special licence, that I, the said Christopher William
Thairlwall, my executors, administrators,_ and assigns, or such others
as I, the said Christopher William Thairlwall, my exccutors, admin-
istrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thercafter during the term therein
expressed, should and lawfully might make, usc, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN MACHINERY
FOR MAKING BRICKS," upon the condition (amongst others) that I, the
said Christopher William Thairlwall, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Christopher William Thairlwall, 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

page_text: in and by the following statement, reference being had to the accom-
panying Drawings forming a part of this Specification :—
My Invention relates to brickmaking machines which have a hori-
zontal pug mill and revolving mould wheel. The pug mill shaft is
furnished with knives, and carries a strong cast-iron worm securely keyed
on its end to force the clay into the moulds in the said mould wheel
when they are opposite the aperture in the discharge box of the pug
mill, which box is somewhat less in size than the mould. The said
discharge box is furnished with a surplus or overflow pipe to prevent
any undue strain on the pug mill shaft when the mould wheel is
turning. The said pug mill is placed on a frame, and is so arranged that
it can be kept in close contact with the mould wheel, and prevent any
escape of clay except into the moulds. The pressure given to the clay
by the worm of the pug mill will vary according to the length of the
discharge nine.
Figure 1 is a side elevation of a machine constructed according to my
improvements; Figure 2 is a longitudinal vertical section; and Figure 3
is an elevation of the same.
Figures 4 and 5 shew detached portions of the said machine.
Like letters indicate the same parts throughout the Drawings.
A is the framing of the said machine; a is the pug mill; b is the
discharge box; and c, the mould wheel or table.
The said mould wheel c has four or any other convenient number of
moulds & extending inward from its periphery, and provided with moving
or sliding bottoms d', connected internally by wrought-iron rods or
bolts d, as shewn in Figure 2, and in such manner that the pressure of
clay from the pug mill in filling one mould discharges the bricks from
the opposite mould; or the same result may be obtained by an internal
cam motion.
Under the mould wheel c, and perpendicular to the axis or shaft e of
the pug mill, is a hollow plunger f working in grooved bearings fixed
in the frame A of the machine, and which is moved up and down by a
cam f¹ upon a shaft g immediately under the mould wheel c. The
bearings * of the shaft g are fitted to slide in the said frame, and are

page_text: kept in position by two levers g', g³, which are provided with weights g³,
and are arranged and operate in such manner as to give the required
pressure to each brick in the moulds: This pressure may be varied as
required, according to the nature or quality of the clay, by adjusting the
weights on the said levers, and this capability of adjustment will
prevent the possibility of any accident to the machine, as when the limit
of pressure to which the same is regulated is reached the said levers
with the bearings of the shaft g will yield. The movement of the
mould wheel c is intermittent, and is effected by the application on onc
or both sides of the wheel of a rocking bar h, which operates a pawl
catch ', and which receives its motion from a crank pin i on a large
toothed wheel j, as clearly shewn in Figures 1 and 4.
The aforesaid plunger is provided with holes for the exit of the air
and surplus clay whilst the brick is being pressed in the mould. To
prevent the adhesion of the clay to the said plunger the same is kept hot
by passing steam through it by means of flexible piping. It is also fitted
with a self-acting lubricating brush k, to be used when steam cannot--be
conveniently applied, and which is supplied with oil from an oil cistern /¹
above the mould wheel c.
The said mould wheel, as shewn in the Drawings, is arranged to make
a quarter revolution at each movement, and is held during the pressing
of each brick by a spring catch or trigger l. The said mould wheel has
on its shaft a disc with four notches 1, 2, 3, 4, corresponding with the
four moulds, and the said catch or trigger is forced by its spring into
each of these notches as they come into the proper position; but it is a
obvious that the said wheel may be provided with any convenient or
desired number of moulds and notches, and may be caused to turn any
required distance at cach movement. The said trigger has a rod or
bar
provided with an antifriction roller 1, which works in contact with
a cam m. Immediately before the action of the aforesaid pawl catch 7¹ {
the said cam m withdraws the trigger from the notch in which it last
engaged, and releases the mould wheel b, which then makes another
partial revolution, these successive operations being repeated during the
working of the machine.
The said machine has a short cross shaft o driven by a belt and pulleys, 3
and provided with a small pinion p, which imparts the required motion
to the cam shaft wheel. It also has a bevil pinion a working into a

page_text: bevil wheel q¹ on a horizontal shaft, on whose opposite end is a toothed
pinion 7 giving motion to the large toothed wheel e' on the pug mill
shaft c.
This large wheel is loose on the said pug mill shaft, and
transmits its power to the said shaft through a brake straps and wheels'.
The said brake wheel is fast on the shaft e, and the brake strap & is
passed around it, and attached to the said toothed wheel. This strap
will bind upon the brake wheel s¹ with sufficient pressure to rotate the
shafte under ordinary circumstances, but if any large stone or the like
should be thrown into the pug mill the brake strap & will slip and
prevent the breakage of the pug mill shaft or of the knives e² or the
worm e³, or other parts of the machine. The pug mill shaft e is provided
with collars e', which run in a grooved bearing e similar to the thrust
bearing of a screw propellor, and which resist the endwise strain on the
said shaft.
I may also modify this machine by constructing it without the pug
mill and gearing connected with the same, and cutting off the part of
the frame behind the rocking bar which gives the intermittent motion to
the mould wheel. In this instance I uso a plunger operated from the
rocking bar shaft for feeding the green brick or clay into the mould; or
I may use it for making bricks of dry ground clay fed from a hopper
fixed on the frame of the machine above a plunger, so arranged that
the clay falls in sufficient quantity to form a brick into a trough in
which the plunger works, and by. which it is pushed forward into the
mould, and is afterwards pressed into the form of a brick by the cam
plunger, as above described.
My improved machine is self-contained. The arrangement of gearing
is neat and compact, and there is no possibility of breakage from over
pressure, and the pressure can be regulated to suit any material. Should
the apparatus which imparts the intermittent motion to the mould wheel
fail to act at any time no accident will occur. Accidents to the pug
mill
are prevented by the use of the frictional apparatus or brake through
which motion is imparted to the pug mill shaft, and all wearing parts of
the machine can be renewed at a very slight cost. The bricks made by
this machine are as hard as it is possible to make really good hard plastic
or semi-dry bricks; and if the materials are first properly prepared the
said bricks will resemble ordinary hand pressed facing bricks, with a
panel on both sides.

page_text: Having thus fully described my said Invention, and the manner of
performing the same, I wish it understood that I claim,-
First. A machine for making bricks with a rotating mould wheel
arranged in combination with the mechanism for delivering the clay to.
the moulds for compressing it therein for regulating or controlling the
pressure for imparting the required intermittent motion to the mould
wheel for discharging the bricks from the moulds, and with the pug mill
and the aforesaid brake wheel and strap, as hercin set forth and for the
purposes specified.
Second. The modification of the said Invention wherein the machine
is constructed without the pug mill and gearing connected therewith, as.
herein set forth and for the purposes specified.
In witness whicroof, I, the said Christopher William Thairlwall, have
hereunto set my hand and seal, this Twentieth day of April, in
the year of our Lord One thousand eight hundred and seventy-
five.
CHRISTOPHER WILLIAM THAIRLWALL. (L.S.)