IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING BRICKS
Year: 1856

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office
of the Commissioners of Patents, with his Petition, on the 10th September
1856. A communication.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING BRICKS," a com-
munication from Isaac Harman, of the United States of America, to be as
follows:-
This Invention relates to an improved construction and arrangement of
machinery or apparatus for moulding bricks, whereby a greater amount
of work is effected in a given time than is accomplished by the ordinary
machinery, and the bricks are rendered more solid and compact.
The main feature of the Invention consists in the employment of sliding
moulds, constructed in two halves, each half having any convenient number of
angular recesses and projections, according to the number of bricks intended
to be moulded at one operation, the two halves of the moulds being so fitted
to each other that when they are put together a number of rectangular
spaces corresponding in size and shape to the bricks to be moulded is left.
A horizontal reciprocating motion is imparted to the moulds by means of
a connecting rod and crank, the two halves of the moulds sliding in suitable
guides fixed to the main framing of the machine.
The tempered clay is fed into the open moulds from a reservoir or feed box

page_text: placed above them, and this feed box extends across and corresponds in shape
to the moulds beneath. A sliding knife is used in connection with the moulds,
and is actuated by rods and levers in such a manner that the moment the
moulds, are filled with clay the knife is pushed forward over the tops of the
moulds, and so cuts off all communication between them and the feed box above.
The cutting edge of this knife is recessed, so as to correspond to the back half
of the moulds, that is to say, its projecting points coincide with the recesses
in the back half of the moulds. To the under side of one half of the moulds is
hinged a radial plate or trap, which is so arranged in connection with levers
and catches as to open and close during the movements of the machine.
When closed this plate forms a bottom to the moulds for the clay to rest upon,
and when open it allows the moulded and compressed bricks to escape and fall
into an endless travelling apron to be conveyed to any convenient locality.
To the upper side of the same half of the moulds is hinged a radial lid, fitted
with a plate and moveable projections, corresponding in shape to the spaces
formed by the angular recesses of the moulds; this lid is alternately raised and
lowered during the movements of the machine by a tail lever acted upon by a
stud pin. It is raised or opened to admit clay into the moulds, and is lowered
or shut down again when the moulds are filled, so that the clay therein may be
confined between it and the bottom hinged plate, and also between the
two halves of the mould, which are now brought together or closed; that is,
their angular projections are made to come in contact with each other, and so
compress the clay contained between the two halves and the top and bottom
of the moulds. On the return or back traverse of the sliding moulds the
two halves open again and allow of the compressed and moulded bricks to
escape, the bottom plate having been previously opened for that purpose. The
escape of the bricks is further facilitated by the moveable projections on the
upper lid of the moulds, which projections act by their weights as pistons
or plungers for forcing the bricks out of their moulds. The moulds having
been thus emptied, are now returned in an open state (that is, with their two
halves out of actual contact,) beneath the feed box, and the knife is withdrawn
to admit a fresh supply of tempered clay, when the operation is completed.