IMPROVEMENTS IN MACHINERY FOR TAMPING OR RAMMING MOULDS FOR CASTINGS
Year: 1884

page_text: I, MATTHEW ROBERT MOORE, of Indianopolis, in the County of Marion and State
of Indiana, one of the United States of America, Engineer, do .hereby declare the
nature of said Invention for "IMPROVEMENTS IN MACHINERY FOR TAMPING OR
RAMMING MOULDS FOR CASTINGS," and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
.
My improvements relate to that part of the operation of making moulds for
castings known as "tamping the moulds" sometimes terined ramming.
This operation, the proper compacting of the material technically known as
sand, as is well known by practical founders, is a most essential part of the
moulders art, for if any part of the material be not sufficiently compressed, it
will not keep in place but is liable to break down or be washed out by the inflow
of the melted metal or forced somewhat outward by the strong pressure due to
even a moderate head of the fluid iron.; and if on. the other hand the sand be
compacted too hard, it will not be sufficiently porous to permit the escape of
contained air, and the vapor and gas given off by the hot material, and the casting
produced will be unsound.
In the operation of moulding, success depends on the skill and judgment of the
workman. Machinery has before been devised for the performance of this
operation, which could be made to produce uniform and perfect results if it were
not for the unevenly distributed space in the mould occupied by the patterns..
These being of various and irregular shapes cause the sand of the mould to vary
in thickness and all parts of the mould being subjected by the machine to the
same amount of compression, the thinner portions are compacted harder than
the thicker. It has been found impracticable therefore to make sand moulds from
patterns of any great variety of thickness by means of any appliances hitherto
invented. By the use of my improvement however, it is practicable to give the
same degree of compactness to every part of the mould whether thick or thin,
[Price 6d 1

page_text: so that uniform and perfect results may be obtained from any variety or dimensions
of patterns. ⚫
My improvement consists in the employment of a flexible diaphragm or yielding
cushion of rubber or other suitable material containing air, water or other fluid,
or plastic substance, through which the pressure is transmitted to the mould.
This I use either alone or in combination with pistons or rammers intermediate
between it and the sand, as hereafter described. The whole surface of the mould
may by this means be subjected to a uniform pressure, but compression only takes
place in proportion to the thickness of the material to be compacted, and the result
is a mould of uniform density or hardness.
.
The accompanying Drawings form a part of this Specification and represent
what I consider the best means of carrying out the Invention.
Figure 1 is a vertical section through the machine in what I esteem its most
complete form.
The remaining Figures represent modifications.
i
Fig. 2 shows the apparatus as arranged without the intermediate rammers, but.
allowing the flexible diaphragm to act directly on the sand.
Fig. 3 shows the same with provisions for working the cover up and down by
fluid applied to the piston in a cylinder above.
*
Fig. 4 shows the apparatus without any means for forcing down the cover.
In this form, the compression of the sand depends on forcing in the fluid above.
Fig. 5 shows a different means of holding the diaphragm; its edges are gripped
tightly between two separate parts of the flask.
Similar letters of reference indicate corresponding parts in all the Figures where
they occur.
When the half of a flask or mould has been filled level full of sand not yet
compacted, and then its upper surface evenly compressed through a space of say
ten inches, as by means of a rigid piston, which fills the top of the flask, those
portions of the sand which lie above the thicker parts of the pattern would be
more compacted than those over the thinner parts, or those parts of the flask
not occupied by the patterns.
Sand, unlike fluids, transmits pressure in direct lines and not laterally to much
extent. But instead of the solid rigid piston or its equivalent, as employed in
moulding machines hitherto devised, I employ a strong movable cover which I will
term a piston, or platen, faced with a diaphragm or cushion of flexible material
loosely filled with air or other fluid, which diaphragm may be brought down upon
the sand with sufficient force. The flexible diaphragm will so distribute the
pressure that the thinner parts of the sand will only yield until they reach that
degree of compactness which will enable them to resist the pressure applied, when
they will cease to be further compressed, while the thicker portions will continue
to yield until every part of the mould has attained a uniform degree of compactness
due to the pressure applied.
Referring to Fig. 1, A is the flask, B the mould-board, C the pattern, and D
the sand. E is a strong supporting bed having hooks F pivoted to points at
the sides.
G is a strong movable cover which may be termed a plunger or piston, and G' a
flexible diaphragm of rubber or other suitable material tightly attached to G by its
edges, the space between the flexible diaphragm, and the plunger G being filled
with water or other fluid as required.
The plunger or piston G is provided with two smooth rods G³, one near each
edge, which traverse in a steadiment provided in a framing M, and serve as guides
to maintain a perfectly parallel position of the piston while it is propelled up
and down by a connection to a crank-pin h, rotated by a shaft H, operated by
a steam-engine or other suitable power not shown.

page_text: G³ is a flexible pipe leading water or other fluid from the pump G or from an
clevated reservoir or other efficient means of furnishing fluid under pressure. It
is controlled by a valve g.
Another valve g¹ serves as a means for discharging the water whenever it is
.desired to collapse the diaphragm.
As here shown the piston G is provided with a stout rim G*, projecting downward
a considerable distance on all sides.
I I are a series of bars of hard wood or other suitable material laid side by side
and gently compressed together by an encircling clamp I, which is by rods į
suspended to the piston.
The pressure of the clamp I on the bars I, should be sufficient to overcome the
gravity and cause them to rise with each elevation of the piston, but not so
great as to forbid their easily accomodating themselves to varying conditions
in the sand below.
To operate the Invention the flask A, having patterns C, and filled with
moulding sand of the proper composition and dampness, not rammed, is brought
into position on the bed E while the piston G with its attachments is in its
elevated position. Then the shaft H is turned and the piston caused to descend.
It is arrested with the crank near its lowest position, and the hooks F are moved
inward and caused to engage over the edge of the piston. Then the valve g is.
opened by the attendant, and the fluid flows through the pipe G³, into the space
between the piston G, and the flexible diaphragm G¹, creating a uniform and
increased high pressure there. Next, the valve g is closed and the shaft turned
rapidly. This elevates and depresses the piston as many times as may be desired,
striking a series of blows pressing the lower ends of the bars I upon the sand.
The sand yields irregularly, the bars being all urged down uniformly by the
uniform pressure of the fluid on the diaphragm. Those bars which come over a
high part of the pattern, press the sand down but little, while those which come
over a thin portion press it down further. The clamp I¹ allows the bars to change
their positions as required, and ultimately all come to rest in the required irregular
position.
After the sand-has been thus compressed first by direct pressure and then by
the blows, the valve g¹ is opened and a large portion of the fluid is allowed to
escape. The shaft is turned to bring its crank-pin h into the highest position,
thus correspondingly` elevating the piston and its attachments, and the flask is
removed.
An inverted box or analogous device having a plane upper surface, is now
introduced in place of the flask, and by striking one blow the bars are again
evened or brought all to a uniform level. Then removing that plane device and
introducing the next flask, the crank is again depressed, the pressure of the fluid
again applied, the hooks are again engaged and the operation is repeated. After.
each flask is removed with a liberal quantity of sand properly compressed in
immediate contact with the mould, the irregular upper surface may be easily
evened by adding more moulding sand, rammed, and the operation is complete.
L is a gauge by which the amount of pressure induced by the fluid is indicated.
Fig. 3 shows a different application of my elastic or yielding piston in which the
sand or moulding material is compacted by beating alone.
Fig. 4 shows the elastic diaphragm as used without the reciprocating or beating
motion when pressure is applied by forcing in water, compressed air steam or other
fluid conveyed to its interior through a hose as shown, the pressure being regulated
by means of a valve g and indicated by a pressure gauge L.
In such case the cover having the diaphragm attached, must be clamped to the
flask, and for convenience may be suspended from a crane.
In the form of the apparatus shown in Fig. 5 the diaphragm of thin india rubber
or analogous elastic air tight material Q' is extended across over the sand and held
at its edges by being tightly clamped between separable parts of the flask. The.
t.
!

page_text: effect of the air pressure applied through the hose-pipe G³ as in the form before
described, is to depress the sand to different extents according to the depths to
which the sand may yield and thus induce uniform firmness in all parts of the
mould.
'
In any of the forms shown, the flexible diaphragm and piston may be made
sectional or multiple consisting of any number of diaphragms separate or conjoined,
and operating independently or together as may be best adapted to the work.
Thus in Fig. 3, the piston and cylinder might be replaced by any number of smaller
pistons and cylinders aggregately equivalent, and operating independently or
simultaneously. So also in the other forms shown; I do not confine myself to the
use of the yielding piston or diaphragm singly, nor to any particular multiple of
it. The sectional or multiple form affords convenient means of adaptation to
moulds of different sizes.
I can use the elastic diaphragm.or piston as shown, or I can combine it with any
other suitable machinery for filling the flask.with sand or other moulding material
automatically or otherwise, and for placing and withdrawing the patterns and
handling the completed mould, and I propose to use any and all such applications
and combinations as required.
:
Modifications may be made in the proportions and arrangements of various
parts. The hooks F may be applied on all sides or only on two sides. For the
latter purpose it is preferable to arrange them on the two sides adjacent to the
uprights of the framing, leaving liberal clear spaces on the other two sides through
which to introduce and remove the flask.
My Invention may be operated to give successive blows while the last instalment
of sand is being filled in, any convenient mechanism being used to automatically
regulate the height of the flask or stroke of the piston to suit the amount of
material to be compressed.
In moulding a number of similar articles successively, the parallel bars and the
diaphragm need not be evened between the several operations, but having been
made to assume the required relations in treating the first flask, those portions of
the bars II and the diaphragm G' relatively to each other, may be maintained in
ramming all the succeeding flasks.
I believe it practicable to effect the compression to a proper extent for some
classes of moulds by the natural pressure of the atmosphere. In such case I can
employ hollow patterns of coarse unglazed earthen ware, or other sufficiently
coarse porous material, and exhaust the air from the interior of the pattern through
a pipe N: as shown in Fig. 5. The diaphragm G' prevents the air from percolating
through the sand, and causes it to act with substantially the same effect as when a
plus pressure is employed. In this mode of working, the means for holding the
diaphragm G' down to.make a tight joint around its edges serve sufficiently as an
equivalent for the platen.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is
First. In combination with a flask A and mould-board B, the platen G. having
flexible diaphragm G¹ means as G³ Gg for supplying fluid to said diaphragm, and
means as g for carrying off such fluid, as herein spécified.
Second. The combination with the platen G, having flexible diaphragm con-
taining fluid, of the shaft H, crank pin frame M and rod G2 and connecting.
pitman, substantially as set forth.
Third. In a machine for making moulds for castings, the combination with a
flask A the support or bed E of a platen G, hooks or locking means F, flexible
diaphragm G', and provisions as G³, G, g, g¹, and connected ineans for applying
fluid pressure between the diaphragm and the piston as herein specified.
Fourth. The method described of tamping or ramming moulds for castings in
placing a flexible diaphragm over the sand, and applying pressure thereto so as to

page_text: depress the sand unequally according as a greater or less depth of sand is presented
to be compacted, all substantially as and for the purposes herein specified.
Dated this Fourth day of June A.D. Eighteen hundred and eighty four.
Witnesses,
WILLIAM FOSTER LUPTON.
ROLLIN EBENEZER DEFREES.
MATTHEW ROBERT MOORE.
G. G. M. Hardingham,
Agent,
191, Fleet Street, E.C.