IMPROVEMENTS IN BRICKMAKING MACHINES
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by Peter Bawden at the Office of
the Commissioners of Patents, with his Petition, on the 21st October
1874.
I, PETER BAWDEN, of 49, Norland Square, Notting. Hill, in the County
of Middlesex, do hereby, declare the nature of the said Invention for
"IMPROVEMENTS IN BRICKMAKING MACHINES," to be as follows:-
My Invention relates to an improved machine for making bricks,
cither by "pallet moulding", or by "slop moulding," that is to say,
either by sanding the mould or by dipping it in water.
This improved machine is particularly adapted for making fire-bricks,
inasmuch as the clay is worked soft, that is to say, of about the same
stiffness as for hand moulding, whereas in most other machines the clay
is necessarily worked stiffer than is suited for fire-bricks.
The machine will also make the best facing bricks in a sanded mould
without any of the sand flaws which inevitably occur in hand moulded
bricks, in consequence of the sand which becomes incorporated with the
clay each time a brick is moulded, by reason of the surplus clay struck

page_text: VIE
brick.
My improved machine comprises a pug mill in which revolves a
vertical shaft carrying clay knives, and which is the main driving shaft
of the machine. At the lower end of this shaft are four blades or knives
of peculiar shape, the blades being inclined upwards from the boss to
their extremities as well as being inclined obliquely, so as to gather the
clay and force it through openings on either side near the bottom of the
pug mill into press boxes, whence it is expressed through a die into a
mould placed to receive it. As both sides of the machine are precisely
alike it will suffice to describe one side only.. In each press box works
a plunger operated by a connecting rod from a crank shaft above driven
by bevil gear from the main shaft. At the bottom of the press box is a
hole or die of smaller dimensions than the interior of the mould in which
the brick is to be found, such hole or dic being narrower at the middle
than at the ends, so that the clay to form a brick as it is expressed into
the mould will have concave sides, in order that the pressure may be
more equally distributed and the clay forced well into the corners of the
mould. The opening leading from the pug mill to the press box is
provided with a moveable shutter to regulate the delivery of the clay.
The moulds (of which for convenience and rapidity there are several
in use successively are the same in form as those used for hand
moulding, and fit closely under the die at bottom of the press box.
The clay forced through the said die is received in the mould and pressed
therein by the plunger, after which the mould is pushed from under the
die and the moulded brick removed therefrom in the usual way. The
press box is provided with a door at one side kept closed by a spring of
sufficient strength to cut off the clay as the mould is pushed from under
the press box, but which will yield in the event of a stone or hard
substance getting partially into the mould and prevent damage.
For pallet moulding a number of pallet boards are placed one on the
other in a box having an opening at bottom, at which the lowermost
pallet board may be drawn out of the box by a pusher attached to a
pusher bar operated as hereafter described; above this opening is a
hopper to contain sand which falls on to the pallet board as it is drawn
out of the box, the layer of sand being regulated in thickness by an
adjustable gauge and smoothed by a roller. The pallet boards are

page_text: pushed on successively towards the press box, at one side of which the
empty moulds which are sanded by hand are piled the one on the other,
and drop successively on the pallet boards as they come under them. A
second pusher on the same bar pushes the lowermost mould together
with the pallet board on which it rests under the die of the press box,
where it receives the clay to form a brick as before described, and is then
pushed from under the die by the next succeeding empty mould, as
before described. The pallet boards move along a bed furnished at that
part which is beneath the press box with friction rollers, to cnablo the
pallet board to readily pass along with the full mould from under the
press box, the said rollers being each furnished with scrapers to keep
them clean.
The pusher bar is moved to and fro the required distance by
connecting rods, and a bell-crank lever operated from the same crank
which works the press plunger, and to prevent damage to the machine
by a mould catching against the press box or other obstruction to the
pusher bar; the latter is made self-releasing by the connecting rod by
which is operated not being attached directly thereto, but by means of
a stud working in a right-angled slot in a lever pivoted to the pusher bar
and weighted, so that the stud will be retained in the vertical part of the
slot until an obstruction occurs, whereupon the slotted lever will be
tilted and the stud released, and moved to and fro in the horizontal part
of the slot without moving the pusher.