IMPROVEMENTS IN MAKING SAND MOULDS AND MACHINERY TO BE USED THEREFOR
Year: 1884

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I, JAMES YATE JOHNSON, of 47, Lincolns Inn Fields, in the county of Middlesex,
Gentleman, do hereby declare the nature of said invention for "IMPROVEMENTS IN
MAKING SAND MOULDS AND MACHINERY TO BE USED THEREFOR a communication
to me from Ernst Körting of 62 Celler-Strasse Hanover, kingdom of Prussia
German-Empire, Engineer, to be as follows:-
This invention relates to the process of making molds in sand for metal castings,
and it consists in compressing the sand upon the pattern by means of a roller,
instead of ramming it with a tamping-bar, or of exercising a vertical pressure on
the whole surface of the sand at once. The improved method is especially adapted
for making molds from long patterns of nearly uniform section. When the rollers
are small, they may be operated by hand, and in such case they are mounted
rotatively on an axle, projecting on either side sufficiently to be laid hold of by the
operator. Large and heavy rollers, however, require to be worked by machinery.'
The axle of the roller may for instance be provided with pinions keyed thereon
and gearing with racks, arranged to oscillate on fixed horizontal pivots. The axle
being then turned by means of cranks attached to their ends, the roller will be
forced to roll upon the sand contained in a flask which is placed between the racks,
while at the same time the pivoting connection of the latter allows the roller to
rise and fall according to the inequalities of the surface of the sand. The roller
may, however, also be worked by means of chains, straps or ropes, and the aforesaid
racks may be provided with means to keep them always in horizontal position
while they move up and down.

page_text: 1, JAMES YATE JOHNSON, of 47 Lincoln's Inn fields, London, do hereby declare
the nature of this invention for "IMPROVEMENTS IN MAKING SAND-MOULDS AND
MACHINERY TO BE USED THEREFOR," and in what manner the same is to be per-
formed, as communicated to me from abroad by Ernst Körting of 62 Celler Strasse,
Hanover, Kingdom of Prussia, German Empire, Engineer, to be particularly
described and ascertained in and by the following statement :-
This-invention-relates-to-the-making-of-molds-in-sand-for-metal-castings,
and it
1
consists in compressing-the-sand-upon-the-pattern-by-means-of-a-roller-adapted-to-
the form thereof and acting by gravity, instead of ramming the sand with
a tamping-bar, or of exercising a vertical pressure on the whole surface of the
same at once. The improved method is especially adapted for making molds from
long patterns of nearly uniform section. While being moved forward over the
loose sand in the molding flask, the roller, on account of its round form, always
operates but on a small surface, and thus nets with considerable power to press the
sand against the pattern and into the cavities of the same, so as to produce
-perfect-copy-thereof._The_form_of_the_roller_has_to_correspond_to-the-sectional
shape of the pattern, in such a manner that the layer or layers of sand compressed
around the pattern will, in transverse section, be substantially of uniform thickness.
In finishing the mold, a cylindrical roller may, however, be used. When the rollers
are small, they may be operated by hand, and in such case they are mounted
rotatively on an axle projecting on either side sufficiently to be laid hold of by the
operator. Large and heavy rollers, however, require to be worked by machinery.
A machine serving for this purpose is represented on the annexed sheet of
drawings. Fig: 1 is a front view, Fig: 2 a plan (in both figures a portion of the
machine being omitted), and Fig: '3 a transverse section thereof. Figs: 4, 5 and 6
show. rollers of various forms such as may be required for different kinds of
patterns.
In Figs: 1, 2 and 3, A is the pattern to be molded, B the molding flask and
C the roller. The said flask is placed in parallel position between the two racks c
which are attached by horizontal pivots e to the standards f. With these racks
gear the pinions b keyed on the axle a passes loosely through the roller C, and
on the ends whereof are fixed the cranks g. The pinions b are kept in gear with
the racks c by means of frames or brackets d, carried by the axle a and embracing
the racks. When, with this arrangement, the axle a is rotated by means of the
cranks g, the pinions b will roll on the racks, and the, axcle, in moving forward or
backward according to the sense of rotation of the cranks, will take along with it
the roller C, and cause it to roll on the sand in the flask B. During this operation
.the connection of the racks c to the standards by means of the pivots e allows
the roller to rise and fall according to the inequalities of the surface of the Band,
and to act thereon by its own weight and the weight of the racks.
The roller, instead of being worked by means of racks and pinions, as described,
may also have motion imparted to it through the medium of chains, straps, or ropes.

page_text: Moreover, if preferred, the racks c may be connected at both ends to standards by
parallel links, which allow the racks to rise and fall, but always keep them in
horizontal position.
•
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, as communicated to
me by my correspondent, I wish it to be understood that I am aware that hereto-
fore rollers have already been employed for compressing sand in a mold-box without
any pattern in it, the cavity for the metal being forined subsequently. Morcover
have rollers been used presenting on their periphery circular patterns, and adapted
to produce the mold by their rolling motion, and in this case, as in others, they have
been positively guided by straight ways. An employment of rollers as accessories
to tamping-bars or rammers has also been proposed. therefore do not broadly
claim the use of rollers in making sand molds; but I declare that what I claim as
my invention is
1. The process of making molds in sand for metal castings by compressing the
sand on the pattern by means of a roller corresponding to the form of the pattern,
and which, while being moved over the surface of the sand, acts thereon by gravity,
substantially as hereinbefore described.
2. In a machine for making molds in sand for metal castings by compressing the
sand on the pattern by means of a roller corresponding to the form of the pattern,
the combination, with such roller, of mechanism adapted to move the roller forward
-and-backward-on-the-sand,-and-to-allow-it-to-act-thereon_by_gravity, substantially_
as specified.