AN IMPROVED METHOD OF PREPARING CLAY FOR THE MANUFACTURE OF BRICKS, TERRA-COTTA, AND OTHER MOULDED ARTICLES
Year: 1878

page_text: LETTERS PATENT to John Ryder, of Openshaw, near Manchester, in the County
of Lancaster, Brickmaker; for the Invention of "AN IMPROVED METHOD OF
PREPARING CLAY FOR THE MANUFACTURE OF BRICKS, TERRA-COTTA, AND
OTHER MOULDED ARTICLES."
Sealed the 4th April 1879, and dated the 8th October 1878.
PROVISIONAL SPECIFICATION left by the said John Ryder at the Office of
the Commissioners of Patents on the 8th October 1878.
JOHN RYDER, of Openshaw, near Manchester, in the County of Lancaster,
Brickmaker. "AN IMPROVED METHOD OF PREPARING CLAY FOR THE MANUFAC-
TURE OF BRICKS, TERRA-COTTA, AND OTHER MOULDED ARTICLES."
The object of this Invention is so to prepare clay as to effectually remove and
separate the limestone and other impurities therefrom, and consists, firstly, in taking
the clay as it comes from the clay bed and drying the same, after which it is
crushed by a sufficient pressure to reduce the same nearly to a powdered state
without at the same time crushing the limestone and other impurities; the finer
portion is then separated by a riddling process, and the coarser portion which will
not pass the riddle is put into clear water and allowed to stand until the clay is
turned into slip, which soon takes place owing to its state of dryness. I then take
the semi-liquid clay or slip, together with the stone and other impurities, and pass
the same through a sieve, and the sieved portion is afterwards mixed with the
powdered clay produced by my first process until a sufficient degree of consistency
is obtained to mould into bricks, or terra-cotta, or other articles. By this process
I am enabled not only to get rid of the limestone and other impurities contained
in the clay and so to prevent all blowing or bursting in the articles produced, but
I can utilise qualities and depths of clay in the manufacture of the finer qualities
of bricks and other moulded articles which have hitherto been impracticable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Ryder in the Great Seal Patent Office on the 8th April
1879.
JOHN RYDER, of Openshaw, near Manchester, in the County of Lancaster,
Brickmaker. "AN IMPROVED METHOD OF PREPARING CLAY FOR THE MANUFAC-
TURE OF BRICKS, TERRA-COTTA, AND OTHER MOULDED ARTICLES."
The object of this Invention is so to prepare clay as to effectually separate and
remove the limestone and other impurities therefrom and so to prevent all blowing
and bursting in the articles produced from the clay. My process also enables me
to utilise qualities and depths of clay in the manufacture of the fiuer qualities of
bricks and other moulded articles which have hitherto been impracticable.
I take the clay as it comes from the bed and dry or partially dry it and I then
crush it by any suitable arrangement of machinery which will reduce the clay to a
state of powder, but not crush the limestone and other hard impurities.
On the accompanying Sheet of Drawings I illustrate what I have found to be a
very efficient arrangement of machinery for this purpose, and the after part of my
process, and which consists of a revolving pan A fitted with a perforated bottom B.
C, C, are a pair of light iron runners or rollers, the weight of these rollers being such
that whilst they will crush the clay they are too light to crush or grind the lime-
stone and other hard substances, and I have found these results to be still further
assured by so arranging the bearings of the runners C that the runners themselves
shall not be able to rest upon the bottom of the pan. They should clear the bottom
by about one inch. D'is a fixed pan for receiving the powdered clay as it falls
through the perforated bottom B. E, E, are scrapers attached to the ribs F, F, of
the revolving pan B, and which deliver the powdered clay through the opening G
in the fixed pan ready for the subsequent part of my process.
In carrying out my Invention I throw the dry or partially dry clay into the
revolving pan where it is reduced to a powdered state by the action of the rollers
and falls through the perforations into the lower pan. The powdered clay thus freed
from impurities is raised by the elevator H. and delivered by the workman
through the shoot I into the moulding machine, being moistened in passing by
water issuing from the rose or other spreader J.
In my Provisional Specification I mentioned that the limestone might be put
into water so as to recover the clay still adhering to it, and to be mixed in the forin
Whilst
of slip with the powdered clay as it passes to the moulding machine.
regarding this as the most perfect arrangement for utilising all the clay I would
remark that by allowing the limestone and other impurities to remain in the
revolving pan a sufficient length of time the action of the light rollers as described,
together with the rubbing action of the limestones on each other, so nearly recovers
all the clay that I have not found this part of my process absolutely necessary.
Having thus particularly described and ascertained the nature of this my said
Invention, together with the best methods with which I am acquainted for carrying the
same into practical effect, I wish it to be understood that I do not confine myself to
the precise form of machine described and illustrated, nor to any particular weight
of the runners or rollers, nor to the rollers being clear of the bottom of the pan so
long as they are not sufficiently heavy to crush the limestone and other hard
impurities. The riddling might be an after process. Heavy runners or rollors
raised off the pan would give approximate results, but these I should consider as
modifications of my Invention, I claim-
1st. The improved process of preparing clay as and for the purpose described.

page_text: 2nd. The use of light rollers or equivalent mechanical arrangements for crushing
the clay without crushing the harder impurities, as and for the purpose described.
In witness whereof, I, the said John Ryder, have hereunto set my hand and
seal, this 7th day of April, in the year of our Lord One thousand eight
hundred and seventy-nine.
JOHN RYDEK. (L.S.)