IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE OF CLAY
Year: 1862

page_text: LETTERS PATENT to James Craig and Matthew Craig, of Kilmarnock, in
the County of Ayr, North Britain, Fire-clay Manufacturers, for the
Invention of "IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE OF
CLAY."
Sealed the 2nd June 1863, and dated the 6th December 1862.
PROVISIONAL SPECIFICATION left by the said James Craig and Matthew
Craig at the Office of the Commissioners of Patents, with their Petition,
on the 6th December 1862.
We, JAMES CRAIG and MATTHEW CRAIG, of Kilmarnock, in the County of
Ayr, North Britain, Fire-clay Manufacturers, do hereby declare the nature
of the said Invention of "IMPROVEMENTS IN APPARATUS FOR THE MANUFACTURE
OF CLAY," to be as follows, that is to say:-
This Invention relates to improvements designed to render the manufacture
of clay more economical, more easy of management, and more certain and
uniform in its results than hitherto.
A portion of the improvements relates to the preparation of the clay or the
working of it up into a suitable plastic condition, and in apparatus embodying
the improvements; the clay after passing through the ordinary grinder is
elevated into a hopper, which delivers it into a revolving cylindrical riddle, and
the riddled clay is elevated into a second hopper, whilst the portions not fine
enough are returned to the grinder. The second hopper delivers the clay into

page_text: a small feeding cylinder, through which it passes into a pugmill of the ordinary
kind. The amount of feed is regulated by the action of a revolving screw
inside the feeding cylinder, by which screw the clay is propelled through, the
speed of the screw being adjusted in relation to that of the pugmill shaft, as
circumstances may require, whilst a kind of overflow duct may be fitted to the
hopper to carry back for re-elevation any surplus clay supplied beyond what
the screw can carry forward.
According to another plan the clay may be fed into the pugmill by means
of an elevator, the speed of which can be regulated by means of a belt and
cone pulleys, such elevator taking up the clay from a hopper or box kept
constantly full by a second elevator, and provided with an overflow duct, by
which the surplus clay returns to be re-elevated. Water is supplied to the
clay in the pugmill by means of a pump driven by a crank or eccentric on
a spindle suitably geared to the pugmill shaft, and the amount of water
supplied is adjusted by altering the stroke of the pump. The connecting rod
from the crank or eccentric is jointed upon a lever fitted with a block movable
more or less distant from the fulcrum by means of a hand wheel, and to this
block is jointed a rod which works the pump either directly or through a
lever. With this arrangement the pump stroke and the consequent supply of
water may be altered with facility whilst the machine is in motion.
Another portion of the improvements relates to the production of clay pipes,
and more particularly to the cutting of such pipes into lengths, being
applicable to the existing arrangements wherein the pipe is expressed in a
downward direction through dies in the bottom of the pugmill. The issuing
clay pipe is received on a table held up by counterweights, but which descends
with the pipe, and it has been usual to cut off the pipe length by a wire in a
frame guided by guides fixed in relation to the' pugmill, this resulting in a
slanting cut being made in consequence of the pipe continuing to issue or
move downwards whilst being cut.
By the present Invention the guides for the cutting frame are connected to
the moving table, so as to move therewith, and the cut is in consequence
made square across whatever motion the pipe may have. The cutting frame
with its guides is made adjustable so as to suit different lengths of pipe, and is
arranged to return to its starting position after each cut.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Craig and Matthew Craig in the Great Seal Patent
Office on the 5th June 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
CRAIG and MATTHEW CRAIG, of Kilmarnock, in the County of Ayr, North
Britain, Fire-clay Manufacturers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of December, in the year of our
Lord One thousand eight hundred and sixty-two, in the twenty-sixth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said James Craig and Matthew Craig, Her special licence, that
we, the said James Craig and Matthew Craig, our executors, admini-
strators, and assigns, or such others as we, the said James Craig and Matthew
Craig, our executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN APPARATUS FOR
THE MANUFACTURE OF CLAY," upon the condition (amongst others) that we, the
said James Craig and Matthew Craig, our executors or administrators, by an
instrument in writing under our, 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 we, the said James Craig and Matthew Craig,
do hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement in writing, reference being bad to the
accompanying Drawings, and to the letters and figures marked thereon,
that is to say:-
Our said Invention relates to improvements designed to render the manu-
facture of clay into bricks, pipes, or other articles more economical; more
easy of management, and more certain and uniform in its results than
hitherto.
And in order that our said Invention and the manner of performing the
same may be properly understood, we have hereunto appended two Sheets of
explanatory Drawings, to be herein-after referred to, and representing portions

page_text: of clay-manufacturing apparatus as arranged with modifications of our
improvements.
A portion of the improvements relates to the preparation of the clay or to
the working of it up into a suitable plastic condition, and consists of improved
means for supplying the clay and the water to the pugmill in a regular
continuous manner, together with arrangements whereby the rate of supply
can be varied, and the quantity of water can be at any time easily adjusted to
suit the condition of the clay.
Figure 1, Sheet 1, of the Drawings represents in elevation as much of the
apparatus as is required for the purposes of explanation, the clay feeder being
shown in section.
In carrying out the Invention, according to one modification, the clay after
passing through the ordinary grinder is elevated into a hopper, which delivers
it into a revolving cylindrical riddle, and the riddled clay is elevated into a
second hopper, whilst the portions not fine enough are returned to the grinder.
The second hopper A is shown in the Figure; it delivers the clay into the
hopper-shaped mouth B of a sinall horizontal feeding cylinder C, through
which it passes into a pugmill D of the ordinary kind. The amount of feed
of the clay is regulated by the action of a revolving screw E inside the hori-
zontal feeding cylinder C, by which screw the clay is propelled through the
cylinder, the speed of the screw being adjusted in relation to that of the pug-
mill shaft, as circumstances may require. To give the power of varying the
speed of the screw E its shaft F (or it may be a shaft in gear therewith) is
fitted with a series of stepped pulleys G to receive a driving belt from
a corresponding series of pulleys on a driving shaft, which is not shown
in, the Drawing. The feed hopper A is fitted with an overflow duct II,
which carries back for re-elevation any surplus clay supplied beyond what the
screw E carries forward; or the duct H may be used to supply clay to some
other apparatus, and it may be fitted with a valve or slide I to regulate the
supply, whilst another duct, which may be supposed to be on the further side
of the duct H may be used to convey away the overflow of clay when there
happens to be any. The elevator supplying the hopper A is by preference
driven at such a speed as to deliver the clay into the hopper at a rate more or
less in excess of the rate at which it is fed forward by the screw E, and by
these means a full feed by the screw is insured, whilst any surplus passes off
by the overflow duct H.
According to another plan the clay may be fed into the pugmill by means of
an elevator, the speed of which can be regulated by means of a belt and cone
or stepped pulleys, such elevator taking up the clay from a hopper or box kept

page_text: constantly full by a second elevator, and provided with an overflow duct by
which the surplus clay returns to be re-elevated. Water is supplied to the
clay in the pugmill D by means of a pump J, driven by a crank or eccentric
on a spindle or shaft suitably geared to the pugmill shaft, and the quantity of
water supplied is adjusted by altering the stroke of the
The crank
pump.
pin K for working the pump is fixed in a groove in the face of a disc L on
the end of the pump shaft, and the throw or eccentricity of the pin K can be
varied. The connecting rod M is jointed upon a lever N, which is in the
form of a small slotted frame, there being in the slot a block P movable more
or less distant from the centre or fulcrum Q of the lever by means of a screw
and hand wheel R. To the adjustable block P there is jointed a rod S, which
works the pump J through the intervention of a lever T and rod U; or the
pump may be worked by a rod directly from the lever N. With this arrange-
ment the pump stroke and the consequent supply of water may be altered with
facility whilst the machine is in motion. It will be obvious that the pump
may be of any convenient kind.
Another portion of our improvements relates to the production of clay pipes,
and more particularly to the cutting of such pipes into lengths, being appli-
cable to the existing arrangements wherein the pipe is expressed in a down-
ward direction through dies in the bottom of the pugmill.
The pipe apparatus, as fitted with our improved cutting details, is repre-
sented in front and side elevation in Figures 2 and 3, Sheet 2, of the Drawings,
the cutting frame being shown in plan in Figure 4. The same reference
letters are used to mark the same parts in each of these three Figures 2, 3,
and 4.
The clay pipe A, issuing downwards from the pugmill B, is received on a
table C, which is guided upon rods D fixed to the pugmill and to a floor
plate E, and which is held up by chains or ropes passing over pulleys F to
counterweights G. It has been usual to cut off the pipe length by a wire in
a frame guided by guides fixed in relation to the pugmill, this resulting in a
slanting cut being made in consequence of the pipe continuing to issue or
move downwards whilst being cut.
By the present Invention the guides for the cutting frame are connected to
the moving table so as to move therewith at the time of making the cut, and the
cut is in consequence made square across whatever motion the pipe may have.
The cutting wire H is stretched across a rectangular cutting frame I, which
is fitted to slide in guide grooves in the side bars J of a wider rectangular
guide frame J, K. This guide frame J, K, is fitted with eye pieces L at the
sides to work upon the vertical guide rods D, and it is held up by ropes or

page_text: chains M passing over pulleys to a counterweighted barrel or pulley N, as
indicated by dotted lines in Figure 2. The guide frame J, K, with the cutter
frame I, is made to descend with the table C and pipe A when cutting by
means of two vertical rods P fixed to the table C, and working up through
guide holes above in the flange of the pugmill B. These rods P also pass
through holes in the side bars J of the guide frame J, K, and these holes are
made with enlargements to allow to pass through them certain wedge-shaped
projections Q, formed or fixed on the rods P. Bell crank latches R are
jointed on the tops of the side bars J, and are acted on by springs S in such a
way as to tend to cover the enlargements of the holes, whence it follows that
as the table C moves downwards with the issuing pipe A and with the rods P
on one of the catches Q coming down upon the latches R of the guide frame,
the continued downward movement will also carry down the guide frame J, K,
with the cutting frame I, keeping these opposite that point of the pipe A at
which they were when the catches Q commenced moving them downwards.
The operator moves the cutting frame I across whilst it is being carried down
in the manner described, and the pipe A is cut squarely across by the wire H.
On the sides of the cutting frame I rods T are fitted, and on these rods two
stops U are adjusted in such positions as to act on the latches R when the
cutting frame I is moved sufficiently across. Thus when a cut is taken the
same action causes the latches R to move from under the catches Q, and the
guide frame J, K, with the cutter frame I being thereby released is at once
drawn up to its normal position by the action of the counterweights. The
length of pipe cut off will obviously depend upon the positions of the catches Q
on the rods P, and these catches are therefore placed to suit the lengths
wanted. It is found convenient to have two or more pairs of catches Q, to
give different lengths of pipe, and when the cutter frame is drawn down lower
than is wanted a slight transverse movement of the cutting frame without
cutting the pipe releases the latches, and the frame J, K, rises as far as may
be wanted.
.The arrangements have been described for cutting squarely across, for
which purpose the grooves in the side bars J of the guide frame are made
horizontal, but if a cut of any particular inclination is wanted it can be got by
giving that inclination to the grooves in the guide frame. When the cut is
made the attendant who has been regulating the descent of the table C, by
means of the brake W actuated by the treadle X, relieves the brake, and
allows the table C to drop as far as required to separate the cut pipe A on the
table from the next length above, and the cut pipe is removed on a board V.
previously placed on the table to receive it. The table C is then allowed to

page_text: rise back again by the action of the counterweights G, its motion being,
however, regulated by the brake W. As the rods P rise with the table C, the
catches Q being tapered off towards their upper ends, simply move the latches R
aside on passing them.
Having thus particularly described our said Invention, and the manner in
which the same is or may be performed, we have to state that we do not restrict
ourselves to the precise details herein described or delineated; but that what we
believe to be novel and original, and claim as the Invention secured to us by
the herein-before in part recited Letters Patent is,―
1. The feeding of clay to a pugmill by means of a screw combined with a
hopper filled by an elevator, and fitted with an overflow duct, substantially as
herein-before described.
2. The feeding of clay to a pugmill by means of an elevator, the speed of
which can be varied, and which takes up the clay from a hopper or box filled
to excess by another elevator, substantially as herein-before described.
3. The supplying of water to a pugmill for manufacturing clay by a pump
worked through the intervention of an adjustable lever for varying the stroke
and consequent rate of supply, substantially as herein-before described.
4. The cutting of clay pipes from a pugmill by means of a cutting frame
working in a guide frame, which latter moves along with the pipe whilst the
cut is being taken, substantially as herein-before described.
In witness whereof, we, the said James Craig and Matthew Craig,
have hereunto set our hands and seals, this Third day of June,
in the year of our Lord One thousand eight hundred and sixty-
three.
JAMES CRAIG.
(L.S.)
MATTHEW CRAIG. (L.S.)
JAMES CRAIG.
(L.S.)
MATTHEW CRAIG. (L.S.)