IMPROVEMENTS IN CHILLED IRON ROLLERS, AND METHOD OF MANUFACTURING SUCH ROLLERS
Year: 1883

page_text: LETTERS PATENT to Thomas Miller, of Edinburgh, North Britain for an
Invention of "IMPROVEMENTS IN CHILLED IRON ROLLERS, AND
METHOD OF MANUFACTURING SUCH ROLLERS
"
IN
THE
PROVISIONAL SPECIFICATION left by the said Thomas Miller at the Office
of the Commissioners of Patents on the 6th July 1883.
THOMAS MILLER, of Edinburgh, North Britain
"IMPROVEMENTS IN CHILLED
IRON ROLLERS, AND IN THE METHOD OF MANUFACTURING SUCH ROLLERS
23
My invention relates to cast iron rollers having chilled surfaces, as ordinarily
used for crushing grain or other substances.
It has for its object an improved method of manufacturing such rollers so
that they are more easily and cheaply made than has ordinarily heretofore been
the case.
Such rollers are of comparatively short length, and having wrought iron or
steel spindles or bearings at their ends, and the method ordinarily hitherto
practised in making them has been to cast each roller separately, having a core
parallel or chambered through its centre which is subsequently bored out to
receive the spindles or bearings, but in this method of manufacture there is
considerable waste of time and material, as it is found necessary to cast each roller
of much greater length than its finished dimensions, the superfluous metal
having to be afterwards cut away, whilst each roller has to be separately centred
in the lathe.
Such rollers have also been sometimes made by casting a cylinder of considerable
length having its entire surface chilled in order to obtain the necessary degree of
hardness. This cylinder is then centred in a lathe and after having been turned
is cut into separate lengths equal to that of the rollers which are to be made.
In this method of manufacture there is considerable difficulty in cutting
through the hard, chilled circumference of the cylinder and the process occupies
much time.
My present invention consists first in an improved method of casting the

page_text: cylinder so that those parts of its circumference where the tool is to operate for
the purpose of cutting it into rollers are left soft and are not hardened by chilling.
For this purpose I make and arrange the mould in which the cylinder is cast in
such manner that the parts of the fluid metal which are to be left soft as described
are moulded by contact with sand or other suitable non-conducting material. By
this means the cylinder when centred in the lathe is easily and quickly divided
into rollers of the desired length. In order to prepare the mould for casting the
cylinders I place between every two ordinary chills or stocks in which the chilled
parts of the cylinder are cast, an annular ring of sand or other suitable material
slowly conducting heat, and the interior of such rings against which the fluid
metal comes in contact when cast, may either be of the same diameter as the chills,
or of somewhat less diameter so as to leave recesses in the cylinder where it is to
be afterwards cut as already described.
In order to facilitate the process of boring the ends of such rollers to receive the
centres or spindles as described, I cast the cylinder, with a central cylindrical
opening or core extending from end to end.
Sometimes I make the core so that instead of being cylindrical it is chambered
or increased in diameter for a sufficient length at the middle of each roller, the
external thickness of which is thus decreased and the roller lightened.
Rollers constructed according to my invention are cheaply and quickly made,
and each set of rollers is of the same quality of material having been cast at one
operation and subsequently divided in the manner described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by.
the said Thomas Miller in the Patent Office on the 5th January 1884.
THOMAS MILLER, of Edinburgh, North Britain "IMPROVEMENTS IN CHILLED.
IRON ROLLERS AND IN THE METHOD OF MANUFACTURING SUCH ROLLERS
"
My invention relates to cast iron cylindrical rollers having chilled surfaces as'.
ordinarily used for crushing grain or other substances.
It has for its object an improved method of manufacturing such rollers so that
they are more easily and cheaply made and are of more uniform quality than has*.
ordinarily heretofore been the case.
Such rollers are of comparatively short length and are provided with wrought.
iron or steel spindles or bearings at their ends, and the method hitherto practised
in making them has been to cast each roller separately, having a core either
parallel or chambered through its centre, the ends being subsequently bored out
to receive the spindles or bearings, but in this method of manufacture there is
considerable waste of time and material, as it is found necessary to cast each
roller of much greater length than its finished dimensions require, the superfluous
metal having to be afterwards cut away, whilst each roller has to be separately
centred in the lathe.
→
Such rollers have also been sometimes made by casting a cylinder of considerable
length having its entire surface chilled in the usual way in order to obtain the
necessary degree of hardness. This cylinder is then centred in a lathe and having
been turned is cut into separate lengths each equal to that of the rollers which
are to be made. In this method of manufacture there is considerable difficulty in
cutting through the hard chilled circumference of the cylinder and the process
occupies much time.
My present invention consists first in an improved method of casting the
cylinder so that those parts of its circumference where the tool is to operate for
the purpose of cutting it into rollers are left soft and are not hardened by chilling.
For this purpose I make and arrange the mould in which the cylinder is cast in
such manner that the parts of the fluid metal which are to be left soft when cold
as described are moulded by contact with sand or other suitable non-conducting
material. By this means the cylinder when centred in the lathe is easily and
quickly divided into rollers of the desired length.
In order to prepare the mould for casting the cylinders in the novel manner
described I place between every two ordinary chills or stocks in which the chilled
parts of the cylinder are cast, an annular ring of sand or other suitable material
slowly conducting heat, and the interior of such rings against which the fluid
metal comes in contact when cast, may either be of the same diameter as the
chills, or of somewhat less diameter so as to leave recesses in the cylinder at the
points of its length where it is to be afterwards cut in the lathe as already
described.
In order to facilitate the process of boring the ends of such rollers to receive
the centres or spindles as described, I cast the cylinder with a central cylindrical
opening or core extending from end to end and sometimes I make this core so that
instead of being cylindrical it is chambered or increased in diameter for a sufficient
length at the middle of each roller, the external thickness of which is thus
decreased and the roller lightened. The accompanying drawing is in illustration
of my invention, and shews in section the mould containing the cast cylinder.
a, a, a, a, are the chills or stocks. b, b, b, annular rings of sand or other non-
conducting material. c is a core shewn chambered. d is one of the bolts by
which the parts of the mould are held together. e is the basin to receive the

page_text: melted metal, and f is the cast cylinder.
Rollers constructed according to my
invention, are cheaply and quickly made, and each set of rollers is of the same
quality of material having been east at one operation and subsequently divided in
the manner described.
Having now described my invention and the manner in which it is to be
performed, I claim:
The method of casting, chilled iron rollers in moulds consisting of a sufficient
number of cylindrical chills each equal in length to a single cylinder, the chills
being separated by narrow cylindrical moulds of sand or other non-conducting
material, substantially as and for the purpose herein described and shewn in the
drawing.
Also in combination with such method of casting chilled iron rollers the use of
parallel or chambered central cores, substantially as herein described and shown in
the drawing.
In witness whereof, I the said Thomas Miller have hereunto set my hand and
seal this 4th day of January in the year of our Lord 1884.