Year: 1887

page_text: I, HARRIS TABOR, of 111 Liberty Street, in the city of New York, county of New
York, and state of New York, United States of America, manufacturer, do hereby
declare the nature of this invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement :-
My present invention pertains to improvements in machinery to be employed by
the metal founder in the formation of his sand moulds, to be used in the manufacturing
of metal castings.
My invention will be readily understood from the following specification, taken in
connection with the accompanying drawing, in which-
Figure 1 is a front elevation of a metal founding machine illustrating my invention,
portions of the machine appearing in vertical section, this view illustrating the machine
as arranged for moulding by the direct impression system, that is to say the pattern is
impressed in the body of the flask previously filled with moulders sand, this figure
illustrating also the displacement system by which the quantity of sand placed in the
flask previous to the impression is proportioned in depth at various points to the
character of the pattern, so as to secure substantially uniform density throughout
the mould.
Fig. 2 a side elevation of the same machine, certain parts appearing in vertical
section, and parts being broken away to exhibit matters beyond, the flask with the
parts specially pertinent to the displacement system being omitted.
Fig. 3 a face or bottom view of the stripper-plate with a pattern projecting
through it; and
Fig. 4 a horizontal transverse section of one of the columns of the framing.
In the drawing A represents the framing of the moulding machine, such framing
consisting of a pair of upright columns secured to a sole-plate, and braced at their
tops by a cap-piece, and having their inner sides open, the columns thus being hollow
columns with one open side each.
B, a cylinder, similar to a steam engine cylinder, located in the upper portion of
the framing, and having channel-shaped side wings extending into the hollows of the
frame columns; the cylinder being provided with a piston and a piston-rod and
receiving and discharge pipes, and also a suitable valve by means of which the
1

page_text: pressure medium, be it steam, water, air, gas or otherwise, may be admitted below the
piston, and at the same time discharged from above the piston, or admitted above the
piston and at the same time discharged below the piston, in other words so arranged
as to permit the piston to be forcibly raised or lowered at will, by means of the
pressure medium.
C, tension rods disposed within the hollow columns, the lower ends of these rods
having hooks projecting out of the columns, and the upper ends of the rods being
provided each with a vertical series of holes by means of which the cylinder B may
be attached to the rods at various points of height by inserting pins through holes in
the cylinder wing, these pins passing through similar holes in the rods, slots in the
front faces of the columns permitting the play of the projecting end of these pins.
D, a pin in each of the rods C, projecting out through a slot in the appropriate
column, the pin normally resting in the lower end of its slot whereby the rods are
limited in their downward motion, these pins thereby serving, when thus resting in
the bottom of the slots, to support the rods and also the cylinder B pinned to the
upper ends of the rods.
E, the platen of the moulding machine, the same being attached to the piston rod
of the cylinder, and provided with a flat under surface, the platen having side lugs
projecting into the hollows of the columns and engaging the tension bars therein so
as to be guided thereby as the platen rises and falls.
F, a pattern block consisting of a flat block rigidly attached to the under side of
the platen, and adapted to be removed therefrom at will.
G, the pattern rigidly secured to the under face of the pattern block, and projecting
downwardly therefrom, the pattern appearing in the illustration as consisting of two
brick-shaped pieces with rounded lower faces and of unequal width; this pattern being
a mere exemplification.
H, a stripper-plate having mortices to closely fit around the pattern, but fitting
freely enough to be capable of movement up and down thereon, this stripper-plate
being attached to the pattern block in such manner as to be capable of a limited
rising and falling motion with reference thereto, the attachment being illustrated as
beheaded studs engaging the pattern block, and permitting the stripper-plate to move
close up against the pattern block, and to move downward a short distance but not
enough to become disengaged from the pattern.
J, the moulding table, the same consisting of a wheeled car fitted to run upon a
track disposed between the frame columns, this moulding table having upon its top a
flat plate upon which may be set the moulders flasks, the plate being, however,
readily removable from the table; the interior of the table-car being hollow.
K, a rectangular frame arranged within the table-car just below the top thereof,
and close against the inner walls thereof, this framing being capable of a limited
vertical motion within the table-car, and constituting a pattern-drawing frame when
the machine is used in a certain manner hereinafter specified.
L, lugs projecting from the pattern frame outwardly through slots in the walls of
the table-car, and disposed above the hooks upon the lower ends of the tension bars C,
in such manner that as the tension bars raise the hooks will come in contact with
the lugs.
M, a crank shaft in the table-car, linked to the pattern-drawing frame K in such
manner that by partially rotating the shaft the pattern-drawing frame may be raised
or lowered.
Resting at this point of reference to the details as they appear in the drawing the
modes of operation of the parts referred to will be specified.
Assume the table-car to have its top-plate in position, and that this table has nothing
above it, and that the car has been run out on its track to some convenient locality
where sand may be delivered to it. The moulder places his half-flask upon the flat
top of the table-car. He fills the half-flask with sand either by shoveling the sand
into place or by letting it flow from a chute. The car with its flask full of sand is
now run into the machine. The steam or other pressure medium being let in above
the piston of the cylinder causes the platen E to descend and press the pattern G into

page_text: the top of the sand in the flask. The stripper-plate H will, of course, rise and occupy
a position close up against the pattern block. As soon as the platen becomes subjected
to enough pressure, the entire cylinder will raise and carry with it the tension
bars C until the hooks of the bars engage the lugs L at which time the upward
motion of the cylinder, etc. will cease, and thereafter the piston will exert a com-
pressive force between the platen E and the top of the table. During the exertion
of this force the columns and the axles of the table-car will have been freed from
any of the strains of the pressure, all of the tensional strains being met by the
tension bars C. None of the table-car parts are lifted from the track in this
operation, the only action of the tension bars being to raise sufficiently to firmly
engage the lugs L. The effect of this pressing is to forcibly impress the pattern in
the top of the sand. By admitting steam or whatever pressure medium is employed,
below the piston, the platen E rises and withdraws the pattern from the sand, the
stripper-plate H resting for a short time upon the top of the sand while the pattern
is being withdrawn and thus preventing the sharp edges of the sand mould from
being displaced in the drawing process. This first effect of the relief of the down-
ward pressure or the admission of upward pressure to the piston is to permit the
cylinder and tension rods to settle down to their normal downward position.
It is obvious that if a moulders flask be laid upon the top of the table, as has been
indicated, and the pattern impressed into its top, the sand can only be compacted so
far as permitted by the descent of the platen, the limit being reached when the
stripper-plate comes in contact with the top edge of the flask. The compression of
the sand thus produced would be limited entirely to the displacement effected by
projecting the pattern into the sand. The compression can be carried to any desired
extent by employing a flask with a press-board in its bottom, the action of the
moulding machine being to press the pattern into the top of the sand, and to press the
press-board upward within the bottom of the flask. If desired such a press-board for
the bottom of the flask may be built up of individual yielding elements so that the
pressure will be uniform regardless of the inequalities of the pattern.
After the mould has been thus formed by impressing the pattern into the sand, and
the pattern lifted from the sand as indicated, facing may be dusted on the mould
and the pattern may be again impressed into the mould, thus giving the final finish
after which the pattern is again withdrawn and the car run out from under the
imachine so as to permit the flask to be removed and the process repeated with another
flask.
It is preferable that there be two table-cars, one being employed in the
machine while the other car is receiving its flask and sand, or having its flask
removed.
It will be noticed that the pattern is attached to the pattern block and that the
strippers also attach to the pattern block. By removing the pattern block from the
platen of the machine it carries with it its pattern and stripper, thus permitting
the machine to be readily changed for patterns or for different parts of patterns. The
drawing illustrates the stripper-plate as enclosing the entire outsides of the pattern.
If there was a downwardly open recess in the centre of one of the patterns it is
obvious that an outside stripper-plate cannot serve in stripping the walls of such
recess. In such case a separate internal stripper-plate should be provided and attached
to the pattern block so as to be capable of the same stripping motion as the outside
stripper-plate.
I will now refer to a system in which the sand is compressed downward onto the
pattern, and the pattern withdrawn by a downward motion. In such case the platen E
is left plain, else provided with a pressing surface, of any suitable character, adapted
to enter a flask. The top of the table-car is removed. The stripper-plate is to be laid
upon the top of the car in the place of this removed plate. The pattern, or the pattern
block, if one be employed, is to be attached to the drawing frame K so that the
pattern will project up through the stripping-plate. The crank-shaft M is to be so
turned as to move upward and give it its full normal projection through the stripper-
plate. In this condition the flask is to be placed upon the table-car over the pattern,

page_text: the flask filled with sand over the pattern, and the car then run into the press and
subjected to the pressing action. The car is then to be run out of the press and the
crank-shaft M turned, thus withdrawing the pattern from the sand, through the
stripper-plate, and permitting the finished flask to be removed from the car, and another
one substituted.
Referring now to other devices of the drawing:-
N, indicates a press-board standing on legs upon the top of the table-car.
0, a sand-box encircling this press-board and fitted for vertical movement with
reference thereto, this sand-box being supported on spring legs so as to be normally
sustained in a position with its top edge above the upper surface of the press-board,
and at the same time be capable of yielding downwardly some distance.
P, a half-flask set upon the top of the sand-box, and forming, practically, an upward
continuation thereof.
Q, displacement blocks having a horizontal section conforming substantially to the
contour lines of the pattern employed, these displacement blocks being fitted to freely
slide through mortices in the press-board N, and being supported by springs of
sufficient capacity to hold the blocks upward under the weight of sand which may be
loosely placed in the flask and sand-box above them, and to yield when any material
pressure is brought upon the sand, the result of this yielding of the displacement
blocks being that they move downward until their tops are level with the upper face of
the press-board N.
Oinitting, for the present, all consideration of the displacement blocks Q, assume that
the press-board N is complete without these blocks. In such case the device presents
an example of such telescopic flask as has been referred to.
R, represents sand which has been loosely placed in the flask and sand-box. When
the pattern is pressed downward it will readily impress itself in the soft sand, and the
continued downward pressure of the platen will cause the flask and sand-box to move
downward, the press-board N acting like a piston within the sand-box, whereby the
sand is compacted between the stripper-plate, pattern, and press-board to any desired
extent. It is desirable that the depth of sand-box projecting above the press-board be
such that the proper condensation will be effected when the flask has been pressed
downward so far that its lower end is even with the top of the press-board. The effect
will then have been to transfer the sand from the sand-box into the flask, and to leave
the flask with the bottom of its sand fairly flush with its bottom edge. The press-
board N is illustrated as standing on legs but it may obviously be solid clear down to
the top of the table.
If a deep body of sand and a shallow body of sand both be subjected to compression
through the same distance the shallow body of sand will become the most compacted.
Hence it follows that projecting patterns will cause the sand in the flask to be the
most condensed directly under the pattern parts. It is very desirable to avoid this
lack of uniformity in the density of the sand in the mould. To avoid the difficulty I
have provided means for regulating the quantity of sand which is placed in the flask,
arranging to have a shallow body of sand under the pattern parts, and a deeper
body of sand at the parts where there is no pattern. The displacement blocks Q
secure the desired effect. Before sand is placed in the flask and sand-box they
project upward above the press-board N as indicated in Figure 1. In this condition
the flask and sand-box are filled and the strength of the springs under the
displacement blocks is sufficient to prevent the premature descent of the dis-
placement blocks. This arrangement insures that there is a shallower body of
sand directly under the pattern than elsewhere. When the mould is subjected to
pressure the displacement blocks yield until their upper surfaces are flush with the
upper surface of the press-board, and the sand in the flask is then compressed as before
indicated. The result of this device is that the sand in the flask will be compacted
uniformly at all points. The springs under the displacement blocks tend to push the
blocks upward and the displacement blocks have adjusting nuts S to serve in limiting
this upward motion of the displacement blocks. The nuts can be adjusted so as to
permit more or less upward projection of the flasks through the press-board. If

page_text: it is desired to increase the solidity of the sand directly under the pattern these
nuts are adjusted so as to lessen the normal projection of the displacement blocks.
If it be desired to decrease the solidity of the sand just below the pattern
then the nuts are to be so adjusted as to increase the projection of the displacement
blocks.
It has been previously stated that the contour of the displacement blocks is to
conform substantially to the contour of the pattern forms which are to be pressed in
the sand above them. No special accuracy need be followed in the matter. The
projections of various patterns seldom have flat faces, but practice has shown that it is
not at all necessary to modify the faces of the displacement blocks, as flat faces upon
them will give, practically, perfect results.
It is of course to be understood that many of the features of this invention
are fully available in moulding presses in which the lower portion of the press
moves upward instead of the upper portion moving downward. For instance,
instead of placing the pressure cylinder above, as indicated in the drawing, the
platen E might be a fixed element and the cylinder or some equivalent pressure-
producing device might be employed to press the table upward against the fixed
platen.
The office of the springs under the displacement blocks is merely to counterbalance
the superposed sand, and the counterbalancing may be obviously effected by weighted
levers as well as by springs.
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
1. The arrangement of tension bars supporting the pressure cylinder and adapted
to engage the pressure-receiving table and relieve the frame parts from strain.
2. The arrangement of table with removable top and inner movable pattern drawing
frame and mechanism for moving the frame upward and downward in drawing the
pattern.
3. The arrangement of the press-board to press upward in the flask in conjunction
with a platen provided with pattern and gravitating stripper-plate.
4. The removable pattern block having the pattern rigidly attached to it, and the
stripper-plate articulately attached to it.
5. The arrangement of yielding displacement blocks in the press-board adapted to
regulate the quantity of sand which can be placed in the flask at those parts which are
to come under the patterns.
Dated this 28th day of June 1887.