Improvements in Machines for Making Cores for Castings.
Year: 1899

page_text: Date of Application, 26th Aug., 1899-Accepted, 2nd Dec.,
1899
CUMPLEIE DIEVITICATION.
Improvements in Machines for Making Cores for Castings.
I, ALBERT KNÜTTEL, of Remscheid, Mechanical Engineer, Rhenish Prussia,
Germany, 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 invention relates to an improvement in machines for making cores for
such castings of comparatively small size which are required in large quantities,
such as fittings for instance. It has for its object to make such cores not only
mechanically much quicker than by hand but also to make them more accurate
and uniform and also more durable or harder.
Hitherto such cores have been made by the use of two moulds having half of
the form in each, both being held together by screws and the moulding sand is
then filled in the hollow form and pressed or stamped tight therein, then the
screws are loosened and the two half-moulds are taken assunder and the finished
core is taken out.
By making cores with my new machine, I proceed in a new and different
manner. I make first a core having approximately the same volume of the
finished core, but not yet the exact shape of the same; one half being formed in
a slightly differing mould; by means of strong pressure and by replacing the
differing half mould by a mould of the exact form required for the finished core,
this then receives its true shape. By this mode of working the sand having the
wrong shape is by pressure formed into the true shape and the cores produced
therefore have a very great consistency and are harder than hand made cores.
All the operations thereby are carried out in such a manner that the cores have
not to be transferred from one place to another, or touched by hand before being
completely finished and I have thus succeeded that a boy can make 7 to 8 times
as many cores in the same time as by hand, say 4500 to 5000 cores for pipe
fittings for instance per day.
I attain the desired object by means of the machine described hereafter and
shown on the accompanying drawings, in which
Fig. 1 shows as an example an ordinary water cock for which a core is to be
formed in two views;
Fig. 2 shows the core required in making such a cock also in two corresponding
views;
Fig. 3 shows in three perspective views the moulding plates required with
my new machine:
Fig. 4 shows the making the provisional core by means of the lower and
middle moulding plate;
Fig. 5 shows the provisional core lying in the lower moulding plate, the middle
one being taken off:
Fig. 6 shows the making of the finished core by placing the upper moulding
plate on top of the provisional core in place of the middle plate;
Fig. 7 shows the product thus received lying in the lower moulding plate,
the upper one being taken off;

page_text: Fig. 8 is a vertical view, partly in section along line 1-1 of Fig. 9 of one form
of construction;
Fig. 9 shows a top view of the machine seen below line II-II of Fig. 8;
Fig. 10 is a section of Fig. 8 along line III-III showing the mechanism for
raising the lower moulding plate;
Fig. 11 is a similar view showing the lower moulding plate in its highest
position, ready for being turned round;
Fig. 12 shows a modification of the machine in a vertical section for use with
an intermediate moulding plate to be put on and taken off by hand:
Fig. 13 is a side view of this construction, partly in section.
Fig. 14 is a vertical view seen from the left side of Figure 12;
Fig. 15 is a sectional top view seen below line IV-IV of Fig. 12;
Fig. 16 shows the intermediate moulding plate used with this machine in
cross section and in plan, for being set in place and taken off by hand.
5
In the following description similar or equivalent parts are indicated by the 1
same cyphers or letters. In the machine shown by Figs. 8-11, where the
intermediate moulding plate is mechanically combined with the frame of the
machine, there are fixed on the table 1 of the frame 1 two standards 2 and 3
which at their head are connected by a cross girder 4, to the lower side of which
is fixed the upper moulding plate 6. In the middle of the frame 1 is fixed the
press cylinder 5 of an hydraulic press, the piston 6 of which has a table 7 fixed
to its top and on this rests the lower moulding plate a. This plate can be raised
up to the lower face of the upper moulding plate by the piston 6.
The lower plate is provided at its right and left side with pins 8 which are
supported by studs or poles 9. These are guided in boxes 10 and 11 respectively,
bolted to the table 1 of the frame 1 and at their lower ends are fixed rollers 12.
These rollers rest upon levers 13 fixed each to a spindle 15 to which is also keyed
a lever 14, so that by turning this lever one way or the other the poles 9 can be
lowered or raised and with them the moulding plate a carried in their forked
upper ends. When raised high enough the moulding plate can be swung round
as indicated in dotted lines in Fig. 11.
By means of the segment 14b and the latch 14-(like a locomotive reversing
gear) the amount to which the moulding plate a is raised can be fixed at any
height desired.
A bar 16 arranged in the box 10 prevents the press table 7 from turning on
the piston.
At a suitable distance between the lowest position of the lower moulding plate
and the upper moulding plate is, in the example shown, arranged a third mould-
ing plate e; it is held on the column 3, so that it can be turned round this column
and placed either exactly over the lower plate a or that it can be turned entirely
out of its way (Figs. 18 and 9). The special form of the three moulding plates
is shown in Figures 3-7.
In the plates a and b, in the upper side of the one and in the lower side of
the other, are engraved the half forms of the cores to be formed, so that when
the plates are put one upon the other these hollow forms exactly make together 4
the complete mould of a core. Round about the borders of the forms a groove e
is made so as to form a sharp edge along these borders. This has for its purpose
to cut off superfluous sand and allow it to fall into the grooves, so that when
the plates are pressed together they will fit tightly one upon the other and no
sand will be left between their even faces.
The third plate c is carried on an arm 17 placed with a corresponding eve
round the column 3 and held in proper height by a collar. It is provided with
holes going right through it and corresponding in place and exactly to the
excavations of the plates a and b. At the lower side the edges of the holes f
correspond pretty exactly to the shape of the mould in the lower plate a towards
the upper side they diminish a little, so that a "provisional" core formed in
them, that is to say, a core having nearly the shape of the finished core can be
5

page_text: formed. The thickness of this plate therefore is made so thick that the volume
of sand forming this "provisional core exactly corresponds to the volume of
Band required for the finished core.
"
In order to bring the three plates always exactly upon each other with their
moulds, guide pins 19 are arranged fitting into holes 20, when the plates are put
together.
The manner of working of the described machine is as follows:
By means of the poles 9, rollers 12 and levers 13, 14, fixed on spindle 15 the
lower plate a is raised so much that its upper face touches the lower face of the
plate c. The moulding holes in a and c having been powdered with coal powder,
as is done in ordinary moulding, the holes are filled with sand and this is pressed
tight therein and the superfluous sand is taken off by a scraper moved over the
upper face of the plate c; now this plate is beaten a little, so as to loosen the
sand in its holes and the lower plate is moved downwards. It now contains
the provisional cores as shown in Fig. 5.
The plate c is now turned on its column by 90 degrees so as to bring it out of
reach of the lower plate and this is now raised by the hydraulic press and pressed
firmly with its upper face against the upper plate b. By this operation that part
of the sand standing over the surface of the plate a is formed into the proper
shape of the core given it by the excavations in the upper moulding plate.
While raising the piston and the lower plate, the forked bars 9 are also raised,
so that when the piston and the table 7 are going back again, the moulding
plate a will be caught by its pins 8 in the forked parts of said bars 9 (Fig. 11).
In placing then a suitable piece of sheet metal upon the plate a. holding it by
hand and turning the plate by 180 degrees as indicated in Fig. 11 the cores can
then be taken off and placed away for the drying stove.
By turning the plate a now again by 180 degrees and lowering it in its original
position it will be ready for a new lot of cores to be formed.
The modification of the machine shown by Figs. 12-16 varies from the one
described and shown, only in its exterior form and by the manner of putting
in place and taking off the intermediate moulding plate, in all other respects,
that is to say, with regard of its working it is identical with the first machine
it being merely mechanical equivalents which have been interchanged in order
to make this machine lighter for small works and for making cores for smaller
articles and where a less quantity is required, as will be seen from the description
following:
The piston 6 of the hydraulic press carries the table 7 and upon this is placed
the lower moulding plate a of similar construction as in the preceding case and
underneath the cross beam 4 is fixed the upper moulding plate b. The pins 8
of the lower plate in this case are guided between slots of the side standards 2, 3
of the machine frame and they may be also supported by levers 13 keyed to the
shaft 15, at one end of which is also fixed the lever 14 which, by means of the
latch 14 and the segment 14b, may be locked so as to fix the amount of raising
the moulding plate at any height desired and to be able to turn it as indicated
in dotted lines in Fig. 14. The intermediate moulding plate (Fig. 16) in this
case, instead of being fixed to the machine frame, is provided with handles c
by means of which it can be put in and taken out of the machine by hand, in
all other respects the three moulding plates are of equal construction as those
first described. .
The working of this machine is materially the same as that of the first one,
ut since the intermediate plate is put on by hand, there is no necessity of raising
the lower one for putting on the intermediate plate and set them right for the
formation of the provisional core and it will thus be seen that the differences in
oth are merely such of minor importance and only due to the structure of the same.
Other variations in the building and frame work of the machine and also in
rranging working parts may be made and I do not limit myself to the exact
orms shown when making machines of larger or smaller size.

page_text: 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). In a machine for moulding cores, in combination with a frame 1 standards
2, 3, a cross beam 4 connecting the top ends of said standards, an hydraulic press
cylinder 5 fixed to the table of said frame, a piston 6 working in said cylinder
and carrying a table 7, an upper moulding plate 6 fixed permanently to the
lower side of said cross beam 4, and having the mould of the upper half of the
core to be formed engraved in its lower face, a removable moulding plate a upon
the table of the hydraulic press and having the mould of the lower half of the
core to be formed engraved in its upper side and a removable intermediate
moulding plate having holes worked right through therein corresponding in
exterior outlines to the shape of the core to be formed and of such thickness
that the volume of the said holes coincides with the volume of the upper half
core, the whole as illustrated and described and for the purpose set forth.
2). In a machine for moulding cores, in combination with a frame 1, standards
2, 3 a cross beam 4 connecting the top ends of said standards, an hydraulic press
cylinder 5 fixed in the middle of the table of said frame, a piston 6 working in
the cylinder 5 and carrying a table 7, a moulding plate 6 fixed permanently to
the lower side of said cross beam 4, a moulding plate a held removably on the
table 7, snid plate a having pins 8 at the sides facing the standards 2, 3 an inter-
mediate moulding plate c, capable of being inserted between the upper and lower
moulding plates b and c, respectively boxes 9, 10 bolted to the table of the
frame 1 guiding vertically bars 9 forked at their upper ends capable of carrying
the lower moulding plate a by the pins 8, a shaft 15 fixed to the frame of the
machine, levers 13 keyed to said shaft and supporting by their free ends the
bars 9, a lever 14 keyed to one end of shaft 15 and engaging by a latch 14* with
a toothed segment 14 on the frame 1, the whole as described and illustrated and
for the purpose set forth.
Barmen. the 25th day of August 1899.
ALBERT KNÜTTEL.
Per Karl J. Mayer,
Agent.